|Publication number||US4158163 A|
|Application number||US 05/843,408|
|Publication date||Jun 12, 1979|
|Filing date||Oct 19, 1977|
|Priority date||Oct 25, 1976|
|Also published as||DE2648150A1, DE2648150C2|
|Publication number||05843408, 843408, US 4158163 A, US 4158163A, US-A-4158163, US4158163 A, US4158163A|
|Inventors||Henry R. Eriksen, Hans M. Beierholm|
|Original Assignee||Danfoss A/S|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (7), Referenced by (38), Classifications (9)|
|External Links: USPTO, USPTO Assignment, Espacenet|
E'=(f·k1 +k2) I
The invention relates to an inverter circuit for operating an asynchronous motor of which the rotary speed is adjustable, comprising an inverter having its output frequency regulatable by a frequency regulator, a D.C. supply having its voltage regulatable by a voltage regulator, a desired value input device for changing the output frequency, a voltage measurer and a current measurer each giving an output value, namely a frequency input signal, a voltage measurement signal and a current measurement signal, and a control circuit which processes these output values to form the input values for the voltage regulator and the frequency regulator and has a first comparator which controls the voltage regulator.
In a known inverter of this kind, the operating point is set by means of a potentiometer of which the tapped voltage is compared with a value approximately proportional to the D.C. supply voltage. The frequency is made to follow the supply voltage substantially proportionally. Since the slip and therefore the rotary speed varies with a change in the load of an asynchronous motor, provision is made for slip compensation which increases the D.C. voltage supplied to the inverter and the inverter frequency with an increase in the current. In this way, the speed can be kept approximately constant in a certain operating range.
The invention is based on the problem of providing an inverter circuit of the aforementioned kind which permits the motor speed to be kept constant over a larger operating range and with increased accuracy.
This problem is solved according to the invention in that the control circuit comprises a computer circuit which, from at least two output values and at least one constant, calculates a computed value of the third output value which, together with the first-mentioned output values, gives by way of computation a substantially constant slip frequency for a given desired value, and that this computed value is compared with a value substantially corresponding to the actual third output value.
With this circuit, the three output values are interlinked in the computer circuit in such a way that a constant slip frequency is obtained for the desired frequency value that is fed in. The D.C. voltage supplied to the inverter is regulated so that this condition is maintained independently of the load. The result of this is that the nominal slip for a nominal load also occurs on partial load. This leads to the desired constant speed. This slip frequency can be kept constant even at low loads in that the air gap magnetisation is made substantially proportional to the rotor current, i.e. there is under-magnetisation. This has the further advantage that hunting is avoided of the kind occurring during slip compensation which corrects the frequency of the inverter whilst substantially maintaining the magnetisation.
Even when switching off, no oscillation occurs between the motor and the inverter. The inverter can even be connected to the motor when the latter is already rotating, whereupon the motor changes its speed to that determined by the inverter without first having to come to a standstill.
It is further advantageous that for each load condition a minimum power is automatically set at which neither excessively high magnetic losses occur as a result of a high voltage nor excessively high copper losses occur as a result of an excessively high current. Instead, there will always be a state of equilibrium at which the current and voltage assume an optimum value because they approach this state of equilibrium from opposite sides. If, for example, a motor is suddenly loaded more intensely, the current rises correspondingly because of the higher slip frequency. Consequently, the voltage is regulated to a higher value until the prescribed slip frequency is again reached. During this, however, the current drops, this setting a new state of equilibrium for the current and voltage.
It is also advantageous that no measurements need be undertaken at the motor itself; the measurement signals can be derived directly in front of and/or behind the inverter.
In a preferred embodiment, the computer circuit comprises a computer element with which a value taking the slip frequency into account is introduced and is held constant below the nominal rotary speed at least over the major part of the motor operating range. Since the set slip frequency applies not only to a particular set frequency but also to the main operating range of the motor, one obtains a correspondingly simple lay-out for the computer circuit.
In order that the slip or rotor frequency can be kept constant independently of the load at a set frequency, the formula
I2 /B=f2 ·constant (1)
applies, wherein I2 is the active current in the rotor of the motor, B is the air gap induction and f2 is the slip or rotor frequency. It was found that one can with an adequate degree of accuracy replace the effective rotor current I2 with the stator current I1 which can, for example, be measured on the D.C. side in front of the inverter. The air gap induction can, with sufficiently high accuracy, be represented by ##EQU1## wherein U1 is the voltage applied to the motor, I1 is the active current supplied to the motor, R1 is the ohmic resistance of the stator coil and f1 is the frequency of the inverter. The voltage U1 can be derived in front of or behind the inverter. From (1), and (2), one obtains ##EQU2## which shows that, if the slip frequency f2 is kept constant, a relatively simple relationship exists between the three values I1, U1 and f1. If one introduces the primary active current I1 as the current measurement signal I, the primary voltage U1 as the voltage measurement signal E and the desired inverter frequency f1 as the frequency input signal f, then a computed value can be calculated in the computer circuit from at least two of the stated three output values E, I and f.
A particularly simple computer circuit is thus obtained if it calculates the computed value according to the equation ##EQU3## or a conversion thereof.
In a first embodiment, the computer circuit comprises a division circuit fed with the voltage measurement signal as the dividend and the current measurement signal as the divisor, and a downstream subtraction circuit in which a fixed value is subtracted from the quotient. In this case, the computed value is calculated substantially according to the equation ##EQU4## In a second embodiment, it is ensured that the computer circuit comprises a subtraction circuit in which a voltage-proportional value is subtracted from the voltage measurement signal, and a division circuit fed with the output value of the subtraction circuit as the dividend and the current measurement signal as the divisor. In this case, the calculation of the computed value f' occurs substantially according to the equation ##EQU5## In a third embodiment, the computer circuit comprises an addition circuit in which a value proportional to the frequency input signal and a constant value are added, and a division circuit fed with the voltage measurement signal as the dividend and the output value of the addition circuit as the divisor. In this case, calculation of the computed value I' takes place substantially according to the equation ##EQU6## In a fourth embodiment, it is ensured that the computer circuit comprises a subtraction circuit in which a current-proportional value is subtracted from the voltage measurement signal, and a division circuit fed with the output value of the subtraction circuit as the dividend and the frequency input value as the divisor. In this case, the calculation of the computed value I' takes place substantially according to the equation ##EQU7## If the division circuit is not itself adapted to introduce the factor 1/k1, a computer element introducing the factor 1/k1 can be connected in front of the dividend input or behind the output of the division circuit.
In a fifth embodiment, the computer circuit comprises a multiplication circuit fed with the frequency input signal and the current measurement signal, one of which is multiplied by a first constant, and an addition circuit in which the result of multiplication is added to the current signal multiplied by a second constant. In this case, calculation of the computed value E' is effected substantially according to the equation
E'=(f·k1 +k2)I (9)
In all these cases, the constants are desirably adjustable, for example to enable adaptation to a particular motor.
However, at least one constant may also be dependent on at least one of the three output values, i.e. f, E or I, for example in order also to enable the operating range to be extended to frequencies above the nominal motor frequency.
The frequency generator will in the simplest case be controlled directly by the frequency input signal f. However, it is also possible to control the frequency generator by the computed value f' because this is made to follow the input frequency f during operation.
It is advisable to provide a minimum current generator which holds the current measurement signal at a predetermined minimum value for small values of the measured current. This ensures that the computer circuit will also operate reliably at zero torque or near zero torque without indefinite conditions occurring as a result, because a voltage measurement value near zero and a current measurement value near zero have to be divided by one another.
It is also favourable if the output of the first comparator is connected to the output of a second comparator which compares an adjustable maximum power value with the product of a factor corresponding approximately to the measured current and a factor corresponding approximately to the measured voltage and overrides the first comparator when the product exceeds the maximum power value. Desirably, the maximum power value is set to the nominal power of the connected motor. If such a high load torque occurs at a prescribed frequency that the maximum power is exceeded, the second comparator ensures that the inverter frequency is reduced relatively to the input frequency to such an extent that the load torque can be overcome with the nominal power. In the torque-frequency diagram, this gives a power hyperbola which limits the range in which the motor can be operated without overloading.
Further, it is favourable if the output of the first comparator is connected to the output of a third comparator which compares an adjustable maximum torque value with a comparative value corresponding to the measured current and overrides the first comparator when the comparative value exceeds the maximum torque value. The third comparator ensures that a prescribed maximum current is not exceeded in the motor whereby the maximum torque is also determined because the torque is substantially proportional to the square of the motor current.
Further, the computer circuit may comprise a computer element which introduces a factor proportional to the slip frequency and holds it constant up to about the nominal motor frequency, and a switch element which increases this factor above the nominal frequency. In this way it is possible to extend the advantageous properties of the inverter circuit to an operating range that extends beyond the nominal motor frequency even though the D.C. supply voltage is limited to a certain maximum value, generally the nominal motor voltage. If the slip frequency to be held constant increases with an increase in inverter frequency, it is possible to keep the motor speed substantially constant independently of the load torque without increasing the voltage that has to be applied.
The switch element may in particular be mechanically coupled to the setting device of the desired value input device. This ensures that the slip frequency and the input frequency are changed simultaneously.
For example, the switch element is a division circuit which is in series with the computer element in the form of an amplifier and to which a signal variable with the frequency input signal is fed as the divisor.
Another possibility is for the computer element to comprise an amplifier and the switch element to comprise a feedback resistor variable with the frequency input signal.
In this case, the factor may double between the simple and double nominal frequency and substantially remain at this double value on a further rise in frequency.
In another embodiment, the computer circuit comprises a computer element which introduces a factor proportional to the slip frequency and holds it constant in the operating range up to just below the nominal voltage, and a switch element which increases this factor above this voltage limiting value. In this way, the manner of operation of the inverter circuit remains unchanged in the entire operating range of the motor, even at frequencies exceeding the nominal frequency. Correction of the slip is undertaken only in the upper range of the available voltage.
In particular, the switch element may be controlled by a control signal which is equal to the voltage measurement signal reduced by a current-proportional value, and the voltage limiting value corresponds to about 90 to 95% of the nominal motor voltage. The limiting value of the voltage is thus determined by a prescribed percentage of the magnetising voltage.
A particularly simple embodiment for this is obtained if the computer element is an amplifier disposed between the subtraction circuit and division circuit and the switch element alters its degree of amplification and is controlled by the input signal of the amplifier.
It is advisable if the factor approximately doubles continuously between the limiting value and a value corresponding to the nominal voltage. In this way one ensures proper operation at which there is not yet a reduction below the pull-out point.
In some cases it is also desirable to bring other influences into play by correcting the input frequency signal.
For example, the output of the desired value input device can be connected to the output of a fourth comparator which compares an adjustable maximum current value with the current measurement signal and reduces the frequency input signal relatively to the desired value when the current measurement signal exceeds the maximum current. By means of this feature one can likewise prevent the maximum motor current from being exceeded. The fourth comparator therefore corresponds to the above-mentioned third comparator. In this way one also prevents the pull-out torque of the motor from being exceeded on overload because the frequency is necessarily reduced.
In another embodiment, the output of the desired value input device is connected to the output of a fifth comparator which compares an adjustable maximum voltage with the voltage measurement signal and increases the frequency input signal relatively to the desired value when the voltage measurement signal exceeds the maximum voltage. This prevents a prescribed maximum voltage from being exceeded at the motor because the frequency is necessarily increased. This is advantageous for an intensive delay at full speed.
In a preferred circuit, the output of the desired value input device is connected to the output of a limiting value circuit which, when the difference between one of the output values and the associated computed value exceeds a predetermined limiting value, changes the frequency input signal relatively to the desired value in the sense of a reduction of the difference. The limiting value circuit functions only during a dynamic operating situation when, on starting or changes in torque, strong accelerations or retardations occur. On excessively high acceleration, the motor slip can increase to such an extent that the pull-out torque is reached. On excessively high retardation, the motor can produce such high voltages that the inverter can be impaired. By correcting the input frequency, the limiting value circuit ensures that these effects do not arise.
For example, the limiting value circuit is preceded by a subtraction circuit fed with the two quantities to be compared in the first comparator. The subtraction result is a measure of the difference that could lead to disruptions.
Another possibility is for a second computer circuit to be provided which computes a computed frequency value from the voltage measurement signal and the current measurement signal, and for the limiting value circuit to be preceded by a subtraction circuit fed with the desired value of the frequency input signal and the computed frequency value.
The limiting value circuit will in the simplest case comprise two diodes, particularly Zener diodes, connected in anti-parallel.
The frequency input signal may be set by means of a simple potentiometer. However, it can also be introduced as an impulse series and fed to the computer circuit by way of a digital/analogue converter. This is often desirable because the impulses can be used either directly or by simple division as control impulses for the inverter.
The frequency input signal can also be fed to the division circuit as an impulse series, the division circuit comprising an integrator which integrates the voltage measurement signal between two successive pulses, and that a storage device stores each last integration result. Since the impulse spacing is inversely proportional to the frequency, the integration result corresponds to the desired quotient.
In many cases it is desirable that the voltage measurement device measures the voltage on the output side of the inverter between two phases and the impulses correspond to the frequency of the inverter. Since half-waves are supplied through the output side, each integration occurs during one half wave. In the meantime, until the next half-wave occurs, the integration result can be fed to the storage device and the contents of the integrator can be expunged.
It is also favourable if the current measurement device is associated with an amplifier with adjustable degree of amplification and giving the current measurement signal. In this way, an adaptation to motors of different power can be effected without changing the inverter circuit.
Further, the current measurement signal can be fed to the computer circuit by way of a time element, particularly an RC element. This prevents a disruptive feedback effect on the computed value, particularly the frequency of the inverter, from occurring when there is a certain amount of waviness in the current fed to the inverter.
In order that there is no drop below the pull-out torque of the motor, it is desirable to provide a limiting circuit which limits the slip frequency to about twice the nominal slip frequency. This can, for example, be effected in that a limiting circuit is applied in the path of the frequency signal, particularly the frequency input signal. If the frequency of the inverter and the permissible torque have an upper limit, the slip frequency is indirectly limited.
Advantageously, the voltage measurement signal is fed to a band pass filter of which the output signal is fed in the same sense as the current measurement signal to the third comparator. This counteracts fluctuations in the inverter voltage that might lead to hunting during operation.
It is particularly advantageous to provide a slip-compensating signal generator which delivers a slip compensating signal which is zero up to about the nominal frequency of the inverter and above this has a value increasing with the frequency. In particular, the slip compensating signal generator can be controlled by the same input value as is the computer element determining the factor proportional to the slip frequency. Whenever this factor and thus the slip is changed, slip compensation will occur.
In particular, an addition circuit may be provided in which a first slip compensating signal is added to the frequency signal, particularly the frequency input signal. In this way the effective frequency is increased with a rise in slip frequency so that the motor speed remains substantially constant.
Another possibility is an addition circuit in which a second slip compensating signal is added to the adjustable torque value fed to the third comparator. Whenever the slip frequency has to be increased at higher frequencies of the inverter, the effective torque will in this way also be increased, which permits the torque to be kept constant over a still larger range of speed.
In this connection it is desirable if the second slip compensating signal is fed by way of an amplifier of which the degree of amplification can assume at least two stages depending on the adjustable torque value, the higher stage being associated with a higher torque. This serves for adaptation to the non-linear curves in the operating diagram. In the extreme case, the degree of amplification can be changed continuously.
In a preferred embodiment, the output of the first comparator is connected to a sixth comparator which corresponds to the third comparator but is firmly set to the highest permissible torque. In this way one avoids overloading of the inverter when the maximum torque fed to the third comparator is increased by variable additive components relatively to the set value.
The invention will now be described in more detail with reference to examples shown in the drawing, wherein:
FIG. 1 is a block diagram of an inverter circuit according to the invention;
FIGS. 2 to 4 are block diagrams of three embodiments of the control circuit;
FIGS. 5 to 10 are detailed representations of six examples of the control circuit;
FIG. 11 is the operating diagram of a switchable amplifier;
FIG. 12 is the operating diagram of a minimum current generator;
FIG. 13 is the torque-frequency diagram of the circuit according to FIG. 6, which also applies to FIGS. 7 to 9;
FIG. 14 is the same diagram for the circuit according to FIG. 5 or 10;
FIG. 15 is a circuit diagram corresponding to FIG. 6, which contains additional circuit components and is represented as functional blocks;
FIG. 16 is a diagram corresponding to FIG. 13.
According to FIG. 1, a three-phase mains 1 energises a regulatable rectifier 2. The latter is connected by two D.C. lines 3 and 4 to an inverter 5 of which the three output lines 6 are connected to an asynchronous motor 7. The output voltage U1 of the rectifier 2 is regulatable with the aid of a voltage regulator 8 which, with the aid of a voltage regulating signal Su, controls for example a vibrator. The regulated D.C. voltage U1 is measured by a voltage measuring device 9 that delivers a voltage measurement signal E. The direct current I1 is measured by a current measurement device 10 which delivers a current measurement signal I.
The frequency of the inverter 5 is regulatable by means of a frequency regulator 11 which feeds a frequency regulating signal Sf to the inverter. In addition, there is a desired value setting device 12 which delivers a frequency input signal f. In a control circuit 13, the three output values E, I and f are processed in such a way that the voltage regulating signal Su and the frequency regulating signal Sf operate the circuit so that the motor 7 has a constant slip or rotor frequency f2.
FIG. 2 first of all shows that the control circuit 13 comprises a comparator 14 and a computer circuit 15. In the computer circuit 15, a computed value f' of the frequency is calculated according to the equation (6) from the current measurement signal I and the voltage measurement signal E as well as two constants k1 and k2, the computed value being compared with the input frequency f in the comparator 14. The voltage regulating signal Su and thus the D.C. voltage U1 are changed until the two values f and f' are equal. Regardless of the load torque, this leads to a constant slip or rotor frequency f2 of the motor 7 and thus to a constant speed. The constant k1 is inversely proportional to the slip frequency f2 and the constant k2 is proportional to the winding resistance of the stator of the motor.
In the FIG. 3 embodiment, the control circuit 13 contains a comparator 114 and a computer circuit 115. The latter calculates a computed value I' of the current according to equation (7) from the voltage measurement value E and the frequency input value f, the computed value being compared with the current measurement value in the comparator 114. The voltage regulating signal Su is regulated until the values I and I' are equal. This likewise leads to the desired constant slip frequency.
In FIG. 4, the control circuit 13 comprises a comparator 214 and a computer circuit 215. The latter calculates a computed value E' of the voltage according to equation (9) from the current measurement value I and the frequency input value f, the computed value being compared with the voltage measurement value E in the comparator 214. The voltage regulating signal Su is changed until the values E and E' are equal. This likewise leads to the desired constant slip frequency.
FIG. 5 shows a control circuit corresponding to FIG. 2. The desired value input device 12 comprises a potentiometer 16 of which the tapping 17 is connected by way of a first summating resistor 18 to the inverting input of an amplifier 19. In addition, the inverting input is fed with the computed value f' by way of a summating resistor 20. The output of the amplifier 19 is connected to the voltage regulator 8 by way of a diode 21.
The computer circuit 15 comprises a subtraction circuit 22 to which the voltage measurement signal E is fed in the positive sense and the value k2 ·I is fed in the negative sense by way of a multiplication element 23, e.g. an amplifier. The subtraction result is fed to the divided input 24 of a division circuit 25. The divisor input 26 is fed with the current measurement signal I by way of a diode 27. However, the input is additionally connected to the tapping of a potentiometer 29 by way of a second diode 28. The potentiometer forms a minimum current generator 30 which ensures that the divisor in the division circuit 25 does not become zero at low current measurement signals I. The quotient is fed by way of a resistor 31 to a computer element 32, e.g. an amplifier, in which the quotient is multiplied by the factor 1/k1. This gives the computed value f'. The factor 1/k1 is variable with the aid of a switch device 33. The latter consists of a special potentiometer 34 in the feedback circuit of the amplifier 32 formed by the resistors 35 and 36. The tapping 37 of the potentiometer 34 is mechanically coupled to the tapping 17 of the desired value input device 12. On a change in the input frequency up to the value 1 (corresponding to the nominal frequency of the connected motor), the slip frequency will not alter. Between the single and double value of the nominal frequency, the slip frequency will change from the single to the double value and upon a further increase in the input frequency the slip frequency will remain at the double value.
In the FIG. 6 embodiment, the control circuit 15 differs from that of FIG. 5 substantially in that the computer element 32 for the factor 1/k1 is connected in front of the dividend input 24 as the computer element 38. The amplification factor of this computer element can be switched by a switch element 38' depending on its input voltage, so that, on exceeding a limiting value of the magnetising voltage, the slip frequency f2 will gradually increase from the single to a double value as will hereinafter be described in conjunction with FIG. 11. There is also a comparator 39. The latter comprises an amplifier 40 fed with a maximum power value Nmax by way of a summating resistor 41 from an adjustable potentiometer 42 and with the instantaneous power by way of a summating resistor 43. The instantaneous power is obtained as the output of a multiplication circuit 44 fed with the voltage measurement value E and the current measurement value I. The output of the amplifier 40 is applied to the voltage regulator 8 by way of a diode 45. As soon as the set value N.sub. max has been reached, this comparator takes over the voltage control of the inverter circuit. A further comparator 46 comprises an amplifier 47 fed with a maximum torque value Mmax by way of a summating resistor 48 from an adjustable potentiometer 49 and with the current measurement value I by way of a second summating resistor 50. The output of the amplifier 47 is connected to the voltage regulator 8 by way of a diode 51. As soon as the value Mmax has been exceeded, voltage control of the inverter circuit takes place by way of this comparator 46.
In the embodiment of FIG. 7, only the computer circuit 15 is shown. The rest of the circuit can be like that of FIG. 5 or FIG. 6. The division circuit 25 is, by way of a computer element 52, fed at the dividend input 24 with a voltage measurement value E which is related to the factor 1/k1. The current measurement value reaches the divisor input 26 and can be corrected by means of the minimum current generator 30. The quotient is fed to a subtraction circuit 53 in which a value k2 /k1 is subtracted which is adjustable at a potentiometer 54. With this computer circuit, the computed value f' is calculated according to equation (5).
FIG. 8 shows a circuit corresponding to FIG. 3. The desired value input device feeds the input frequency f' in the form of an impulse series. This impinges directly on the frequency regulator 11. A digital/analogue converter 116 converts the signal to an analogue voltage. By way of a computer element 117 in which the product k1 ·f is formed, the analogue voltage is fed to a summating circuit 118 in which the product has the constant k2 added to it that is derivable from a potentiometer 119. The result of the addition is fed to the divisor input 120 of a division circuit 121 of which the dividend input 123 is supplied with the voltage measurement value E. One thereby obtains the computed value I'. The latter is fed by way of a summating resistor 124 to the inverting input of an amplifier 123 of the comparator 114. This input is additionally fed by way of a summating resistor 124' with the current measurement signal I which can be corrected with the aid of a minimum current generator 30. This circuit gives a constant slip frequency according to equation (7).
The two values I and I' to be compared are additionally fed to a subtraction circuit 125. The difference influences a limiting value circuit 126 which consists of two Zener diodes connected in anti-parallel and therefore gives no output signals at small differences but at large differences gives a comparatively large output signal to an addition circuit 128 by way of a resistor 127. In the addition circuit, the frequency input signal f is corrected in a manner such that on excessive acceleration or excessive retardation, the frequency signal fed to the computer circuit is corrected in the sense of a smaller departure from the frequency of the motor calculated from the measured values.
A comparator 129 comprises an amplifier 130 of which the inverting input is fed with a maximum current value Imax from a potentiometer 132 by way of a summating resistor 131 and the current measurement value I by way of a summating resistor 133. The amplifier output 130 is likewise connected to the input of the addition element 128 by way of a diode 134 and a resistor 135. When the set value Imax is exceeded, a correcting signal is obtained with which the frequency fed to the computer circuit is reduced relatively to the set desired value f.
A further comparator 136 comprises an amplifier 137 of which the inverting input is fed with a maximum voltage value Umax from an adjustable potentiometer 139 by way of a summating resistor 138 and with the voltage measurement value E by way of a second summating resistor 140. The amplifier output is likewise connected to the one input of the addition circuit 128 by way of a diode 141, which is oppositely poled to the diode 134, and a resistor 142. When a maximum voltage Umax is exceeded, the frequency input signal is corrected in a manner such that the frequency fed to the computer circuit is increased.
FIG. 9 illustrates a computer circuit 115 operating according to equation (8). In it the current measurement signal I is provided with the factor k2 in a computer element 143. This product is fed to the minus input of a subtraction circuit 144 of which the plus input is supplied with the voltage measurement signal E. The result of subtraction is fed to the dividend input 145 of a division circuit 146 of which the divisor input 147 is fed with the frequency input signal f. The quotient is related to the factor 1/k1 in a computer element 148. This gives the computed quantity I' which is compared with the current measurement value I in the comparator 114.
Because of the supply of the frequency input signal f as an impulse series, the division circuit 146 is designed so that an integrator 149 integrates the signal at the input 145 between two successive pulses that are fed by way of the input 147. The result of integration is in each case transmitted to a storage device 150 so that it is also available during the course of integration. Simultaneously, or immediately after transmission to the storage device, the integrator is returned to zero.
The FIG. 10 circuit corresponds to FIG. 4 and operates according to equation (9). The computer circuit 215 comprises a multiplication circuit 216 of which the one input 217 is fed with the frequency input value from a potentiometer 218 by way of a resistor 219 and the other input 220 is fed by way of a computer element 221, in which the current measurement value is related to the factor k1, with the current measurement value I corrected by the minimum current generator 30. The product is fed to one input of an addition circuit 222 of which the other input is connected to the output of a computer element 223 supplied with the current measurement value I, so that this input is fed with the product I·k2. The summation result corresponds to the computed value E' of the voltage. This is fed to the inverting input of an amplifier 225 of the comparator 214 by way of a summating resistor 224. The same input is fed with the voltage measurement signal E by way of a summating resistor 226. The output of the amplifier controls the voltage regulator 8 by way of a diode 227.
The computer element 221 is preceded by a division circuit 228 of which the dividend input 229 is fed with the current measurement value I. Normally the value 1 exists at the divisor input 230, this value being tapped from a voltage divider consisting of a fixed resistor 231 and a special potentiometer 232. The tappings 233 of the desired value setting device and 234 of the special potentiometer 232 are mechanically intercoupled in the following manner. When the frequency input value lies between zero and the nominal motor frequency, the divisor has the value 1. Between the single and double nominal frequency, the divisor increases from 1 to 2. Above double the nominal frequency, the divisor remains at the value 2. In function, this corresponds to the FIG. 5 arrangement. In addition a second computer circuit 235 is provided. In a subtraction circuit 236, the product I·k2 is subtracted from the voltage measurement value E. The subtraction result is fed to the dividend input 237 of a division circuit 238 of which the divisor input 239 is fed with the product I·k1. One therefore obtains at the output a computed value f" which is calculated according to the equation ##EQU8## This equation corresponds to equation (6). This computed value f" is compared with the frequency input value f in a subtraction circuit 240. The difference serves as the input signal for a limiting value circuit 241 corresponding to the limiting value circuit 126. Its output value is fed by way of a resistor 242 to an addition circuit 243 so that the frequency input value f can be corrected when the frequency f" calculated from the measured values shows an excessively large difference from the frequency f that is actually introduced.
FIG. 11 shows the operating curve of the computer element 38 designed as an amplifier. Its input value E-I·k2 corresponds to the magnetising voltage. Since at higher motor frequencies and constant slip frequency this magnetising voltage goes beyond the maximum voltage available at the inverter input, this constant slip frequency is maintained only up to just below the nominal voltage (limiting value G) represented by 100% Emax. Thereafter, there is a correction such that the input value 100% Emax also corresponds to the output value 100% Emax, which causes a change in the slip frequency in this upper voltage range.
The operation of the minimum current generator 30 is evident from FIG. 12. When the current measurement value I and thus the active motor current I1 approaches zero on the line A, the minimum current generator 30 takes over the generation of signals along the line B. The value Ikorr that is effective in the computer circuit can therefore never drop below a predetermined value, e.g. 22%, which corresponds approximately to a minimum torque of 5%.
FIG. 13 is the torque-frequency operating diagram of an inverter circuit according to FIG. 6. The operating range extends over a frequency of 0 to 300% of the nominal motor voltage flnenn. The minimum current generator 30 is effective in the entire operating range. For this reason the range C is inoperative for the regulation. Between zero and about 100% of the nominal frequency, the torque is limited only by the horizontal M=100%. This takes place as a result of setting the potentiometer 49. For each operating point lying between the line M=100% and the region C, a constant motor speed is obtained for each desired torque that is determined by the input frequency f and the slip frequency selected by means of the factor 1/k1. In the frequency range between 100 and 200%, these conditions can be maintained up to the line f2 =100%. For a higher torque, there is a higher magnetising voltage which leads to switching over of the regulating element 38 corresponding to FIG. 11. The result of this is that at higher torques the slip frequency gradually increases to double the value. The upper limit that is here effective is the maximum power Nmax which was set by the potentiometer 42 and which leads to a hyperbola N=100%. The motor can even be operated in the frequency range from about 200 to 300%, the same conditions as before being applicable. Only the upper limit is prescribed by the line f2 =200% because on a further increase in the slip frequency one would fall below the pull-out point. From all of this it will be evident that with the aid of the inverter circuit a motor can be operated independently of the torque at a constant rotary speed over an extraordinarily large frequency range and an extraordinarily large torque range and that even at higher frequencies operation will still be possible in the region E if one permits a twofold increase in the slip frequency.
In the diagram according to FIG. 14, which may for example correspond to the embodiment of FIG. 5, the upper limits are the same as in the FIG. 13 diagram. By reason of the potentiometer 34 mechanically coupled to the frequency input potentiometer 16, however, one obtains different conditions below the upper limiting curves. Up to the nominal frequency, there are no differences. In the frequency range from about 100 to 200%, the slip frequency increases in proportion to the frequency increase. Between 200 and 300%, the twofold slip frequency is constant. Since each frequency input signal f is associated with a constant slip frequency f2, no departures from the set speed occur for all the permissible torques.
Extraordinarily high accuracies can be achieved at constant rotary speed with the aid of the principle of the present inverter circuit. With a conventional asynchronous motor, one can in this way keep every set speed constant up to 10% of the maximum speed within a tolerance of ±0.5% within the entire load range from zero up to full load torque.
Still higher requirements can be met with the circuit according to FIG. 15 which is similar to FIG. 6 and in which the same reference numerals are used but which contains still further circuit components. For a better illustration, some of the circuit components are shown as function blocks in each of which the input signal is entered on the abscissa and the output signal on the ordinate in a coordinate representation.
The path of the current measurement signal I contains an amplifier 55 with a variable amplification factor A. This permits motors of different size to be connected to the same inverter circuit even though the inverter circuit itself is designed for only one particular motor size.
If a motor is connected which has a lower nominal power than the nominal power of the inverter circuit, the full load current of the smaller motor would correspond to a partial load current of the larger motor. Consequently the smaller motor would be undermagnetized at full load and would also have insufficient magnetisation at every partial load. This would result in an undesirable higher slip frequency and make it possible for the pull-out torque of the motor to be exceeded. All these disadvantages can be avoided in a simple manner by increasing the amplification factor A in the amplifier 55. If, for example, a motor with half the nominal power is connected, the amplification factor A need merely be doubled. All the operations in the inverter circuit will then be performed at half the motor current.
The current measurement signal is fed to the computer circuit 15 by way of a time element 56, particularly an RC element. The time constant of this element, which may for example amount to 0.2 s, ensures that a certain amount of waviness in the inverter current will not have any effects in the computer circuit 15. In particular, the frequency of the inverter will not change under the influence of this current waviness. This time constant also influences the speed with which the inverter circuit moves to a new operating point. However, the time constant can readily be selected so that the influence of the current waviness is suppressed but the approach to a new operating point proceeds sufficiently rapidly.
The voltage measurement value E is fed not only to the computer circuit 15 but also to a band pass filter 57 which is impenetrable for D.C. voltage but allows an A.C. voltage component to pass to a larger or less extent depending on its frequency. This A.C. voltage component forms the output signal of the band pass filter 57 and is fed in a mixing stage 58 to the comparator 46 in the same sense as the current measurement signal I. The band pass filter is desirably tuned to the resonance frequency of the filter circuit that is conventional for a regulatable rectifier 2. In this way one avoids hunting of the connected motor such as that occurring on a sudden load change with torque control. This hunting become noticeable because of the voltage changes. The A.C. voltage component acts as a feedback.
Since with this regulation the maximum motor current must not be exceeded, a further comparator 59 is provided of which the output is connected by way of a diode 60 to the outputs of the other comparators 14, 39 and 46. This comparator has a subtraction circuit 61 which is fed on the one hand with the current measurement signal I and on the other hand from a voltage divider 62 with a fixed reference signal as the highest permissible current value Imax. This comparator 59 therefore takes over the control of the voltage regulation signal Su as soon as the maximum current has been exceeded. The slip frequency of the motor must not, even under extreme conditions, become so large that one falls below the pull-out torque. This generally occurs when the actual slip frequency is larger than three times the nominal slip frequency. Since non-linear conditions obtain between the slip frequency and torque, which can be taken into account in the computer circuit with only very large expense, it is recommended that the slip frequency be limited to about twice the nominal slip frequency. This can for example be effected by a corresponding design of the switchable amplifier 38, 38'.
However, in the present circuit there is indirect limiting by the limiting circuit 63 which prevents the frequency input signal f from exceeding a predetermined limiting value. If a maximum frequency has on the one hand been set by the circuit 63 and the maximum load has on the other hand been set by the comparator 59, then, conversely, the slip frequency can also not exceed a predetermined limiting value.
This also applies even if additional slip compensaton is provided for. A slip compensation signal generator 64 is influenced by the same input quantity as the switchable amplifier 38, namely the value E-I·k2. With reference to FIG. 11, it will be recalled that at a limiting value G in the switchable amplifier 38 there is a change in the factor 1/k1. Up to this limiting value G, the slip compensation generator 64 gives a slip compensation signal Sk=0. On exceeding this limiting value G, the signal Sk increases continuously. The signal Sk is therefore effective only if the factor 1/k1 responsible for the slip frequency is increased, e.g. doubled. A first slip compensating signal Sk1 is tapped at a potentiometer 65 and superimposed on the frequency input signal f in a mixing stage 66 of an addition circuit. The result of this is that the frequency of the inverter is continuously increased when the slip frequency is reduced by means of the amplifier 38. Consequently, one obtains a high speed constancy. A second slip compensating signal Sk2, which may be identical with the slip compensating signal Sk, is fed to an amplifier 67 which has two amplifier characteristic lines I and II. At low values of the maximum torque value Mmax set at the potentiometer 49, the characteristic line I applies whereas at higher torque values the line II applies. The output value is added to the maximum torque value in an addition circuit 68. As a result, whenever a maximum torque value was set that was not equal to the highest permissible load, the set maximum torque can be kept constant over a larger speed range, as will be explained in conjunction with FIG. 16.
As in FIG. 13, the torque M is applied by way of the inverter frequency f1 in FIG. 16. Three different operating conditions are examined in which the maximum torque was set to 100, 75 and 50%. This corresponds to currents I of 100, 87 and 71%. Above the nominal frequency, the power hyperbolas N of 100, 87 and 71% correspond to these curves. It will be seen that at a torque setting below 100%, the torque above a predetermined frequency f1 drops even though there is torque in reserve. This is exhausted in that the slip compensating signal Sk2 is superimposed on the set torque value M, this superimposition proceeding in the same sequence as the increase in the slip frequency f2. By means of this superimpositioning, one obtains the extended straight torque lines M' and M" from which it is seen that for example a set torque M of 50% can be maintained up to twice the nominal frequency. It should be noted that at higher torques which intersect the power hyperbola at steeper sections, larger additions of slip compensation are necessary than at smaller torques. This is taken into account by the two amplifier characteristic lines I and II of the amplifier 67. It will be clear that a higher accuracy can be achieved if the degree of amplification is changed continuously with the set torque Mmax. The limit at an inverter frequency of 200% f1nenn is the effect of the limiting circuit 63.
The illustrated circuits are merely examples. The computer circuits can be embodied in different ways. For example, instead of the division circuits one may use multiplication circuits at which the divisor is supplied as the reciprocal value. Instead of feeding the one output value direct to the comparator, one can also process it in the computer circuit and then compare two intermediate results with one another.
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|US3983463 *||Aug 29, 1974||Sep 28, 1976||Tokyo Shibaura Denki Kabushiki Kaisha||Method and apparatus for controlling the speed of induction motors|
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|US4019105 *||Sep 26, 1975||Apr 19, 1977||General Electric Company||Controlled current induction motor drive|
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|US4227139 *||May 12, 1978||Oct 7, 1980||U.S. Philips Corporation||Motor control arrangement|
|US4255695 *||Sep 25, 1978||Mar 10, 1981||General Electric Company||Method and apparatus for control of inverter synchronous machine drive system|
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|US4400655 *||May 11, 1981||Aug 23, 1983||Imec Corporation||Self generative variable speed induction motor drive|
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|US4443750 *||Apr 30, 1980||Apr 17, 1984||Zero-Max Industries, Incorporated||Energy saving motor speed controller|
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|US4827202 *||Oct 21, 1987||May 2, 1989||Deutsche Thomson-Brandt Gmbh||Method of and circuitry for automatically adjusting the variable-gain amplification in a control loop|
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|US6229278 *||Sep 29, 1999||May 8, 2001||Rockwell Technologies, Llc||Voltage and current limiting method and apparatus for a voltage/frequency drive|
|US6900614 *||Mar 13, 2003||May 31, 2005||Lg Industrial Systems Co., Ltd.||Rotation speed search apparatus for increasing an output voltage of an inverter and method thereof|
|US6914398 *||Oct 3, 2001||Jul 5, 2005||Abb Ab||Rotary machine control|
|US7915760||Dec 3, 2008||Mar 29, 2011||Evans Sr Bruce Jonathan||Electric power conservation system for storing electric power for use during off-peak hours|
|US8203235 *||Feb 18, 2009||Jun 19, 2012||Liebert Corporation||AC and DC uninterruptible online power supplies|
|US8519651 *||Oct 11, 2011||Aug 27, 2013||Mabe, S.A. De C.V.||Dephasing control|
|US9257935 *||Jan 22, 2014||Feb 9, 2016||Lg Electronics Inc.||Motor control apparatus and method|
|US9692314 *||Mar 17, 2016||Jun 27, 2017||Lite-On Electronics (Guangzhou) Limited||Detection circuit and three-phase AC-to-AC power converting apparatus incorporating the same|
|US20030173930 *||Mar 13, 2003||Sep 18, 2003||Lg Industrial Systems Co., Ltd.||Rotation speed search apparatus for induction motor and method thereof|
|US20040012351 *||Oct 3, 2001||Jan 22, 2004||Bertil Ohlsson||Rotary machine control|
|US20090152952 *||Dec 3, 2008||Jun 18, 2009||Evans Sr Bruce Jonathan||Electric power conservation system|
|US20090256422 *||Feb 18, 2009||Oct 15, 2009||Liebert Corporation||Ac and dc uninterruptible online power supplies|
|US20120086383 *||Oct 11, 2011||Apr 12, 2012||Omar Antonio Hernandez Ferrusca||Dephasing control|
|US20140203747 *||Jan 22, 2014||Jul 24, 2014||Juhyoung LEE||Motor control apparatus and method|
|US20160285381 *||Mar 17, 2016||Sep 29, 2016||Lite-On Technology Corp.||Detection circuit and three-phase ac-to-ac power converting apparatus incorporating the same|
|U.S. Classification||318/798, 363/79, 363/37|
|International Classification||H02P, H02P27/06|
|Cooperative Classification||H02P2201/03, H02P27/06, H02P27/047|


text:
Posted on November 20, 2017
Maximizing the value of a home is the main intention of all homeowners. Some wait for the land value to rise, while the brainier make home improvement tips and enjoy a higher than expected ROI. While you wait for the home prices to rise at its pace, consider these home improvements that add value to your property and these are the best ideas that you can incorporate to scale up the worth of your house. The most baffling part is to figure out which DIY projects for home improvements should be focused on? Concentrate on the part that can boost the value of a home radically and follow that in order to reap the benefits. Without further ado, let us have a look at the major home improvements that add value to chicago wholesale properties for sale.
• Basement/foundation: A poor basement can instantly turn-off any potential buyer especially when it’s damp or in repair, so you should always be concerned and fix it up before someone knocks the door to have a look at your house. A problematic basement can derail the sale entirely, no matter how beautiful the house is. Moisture accumulation, leaks or flooding are some of the most important things to ponder on. As far as basement or foundation problems are concerned, it is always good to be pro-active than wait for future damage. A clean and dry basement will net you somewhere in the neighborhood of just about 70% of your return on investment.
• Yard improvements: Just like front door projects even landscaping is said to scale up the curb appeal of your house. Listed below are some of the things that you can do to improve your exterior:
• A fresh coat of paint: A fresh coat of paint can simply change the look of your house both interior and exterior, however, this can also value or devalue and it’s all a matter of picking the right color. Go for neutral tones, in order to help the prospects imagine themselves living in your house, instead of seeing your personality in every corner of the house. When you are attempting to do so, make sure that you work out in prior to bring out the best results. Avoid deeper shades as it might turn off prospects and opt for soothing, attractive colors that are welcoming.
Lay your hands on these aforesaid home improvement tips and you are sure to see a world of difference and have a healthy ROI to do chicago wholesale properties for sale.Tags: Chicago wholesale properties for sale, home improvement tips, sell your home fast

domain: finance


Puerto Rico's Public Finance Corp. (PFC) failed to transfer funds to pay the principal and interest on its bonds, according to the island's bank and a filing on Wednesday, highlighting cash problems as the island tries to restructure its debt.
The transfer of $93.7 million was for a debt service payment due Aug. 1 by PFC, part of the island's Government Development Bank.
"I think this puts other bond payments in jeopardy," said John Miller, co-head of fixed income for Nuveen Assset Management. "All classes of bonds, as the government has said, are in greater jeopardy of non-payment in the near term."
Puerto Rico's Governor Alejandro Garcia Padilla dropped a bombshell on creditors in June by saying the island needed to restructure debts to solve its fiscal problems, while an adviser to the island said the U.S. territory would soon run out of cash.
The PFC, which provides financing to the island's agencies and is a subsidiary of Puerto Rico's Government Development Bank (GDB), said in a filing it had requested the funds be appropriated in the 2016 budget but they were not included in the budget approved June 30.
"In accordance with the terms of these bonds, the transfer was not made due to the non-appropriation of funds," said GDB head Melba Acosta in a statement.
A source familiar with the situation said no default would be triggered by not moving the funds, as the bonds only require that funds are transferred and paid if they are appropriated.
Moody's analyst Ted Hampton said he had not yet made a determination as to whether it constituted a default.
"Whether this missed payment by itself constitutes a default or not, it does show how pressures on Puerto Rico's liquidity and budgetary process are intensifying," Hampton said in an email.
Hampton said that the GDB had indicated that a supplemental request has been made to the legislature to provide an appropriation for the August 1 payment, "which could avert an actual default on the debt service payment."


What possible problems could exist if the VBUS pin is permanently connected to 5V?
I'm designing a circuit with a PIC32MZ and opto-isolated USB communication.
Only lines D + and D- are isolated so I plan to connect the VBUS pin of the MCU to 5V from an internal source of the circuit.
Necessarily the USB module must detect the 5 V on the host side? (Obviously I should use another optocoupler)
Any suggestions or comments are welcome.


The present owner of this shining Lotus Eleven is no stranger to the type, having owned and raced another Eleven.
Keen to add to his Lotus collection, he found another Eleven in the U.K., though it had been badly crashed — when and by whom is unknown. This car’s long recovery to health began in the early 1980s and included a completely new body from Williams and Pritchard. While most of the damaged panels were discarded, the owner retained the Read More
It was in 1953 that the Maserati A6GCS found its perfect form. Having left Maserati for Stanguellini, Alberto Massimino left a space that was filled by Gioacchino Colombo, known for his work at Alfa Romeo, and the designer of the V12 Ferrari engine that took his name.
Colombo perfected the development of the twin-cam, twin-ignition 6-cylinder engine adapted for the sports version, and with its lightly modified suspension, this became the A6GCS/53.
Marketed as the Maserati Sport 2000, the car Read More
This stunning C-type is just the seventh example of 53 cars in the chassis number sequence, and it wears the ninth body constructed. Chassis number XKC007 also claims important SCCA racing history in the hands of the legendary Phil Hill.
The Jaguar debuted as number 41 at Elkhart Lake in early September of 1952. As his son Derek recalls, Phil Hill actually drove the Jaguar himself from California to Wisconsin for the race. There, Hill won the Sheldon Cup race Read More
All dual-overhead-camshaft engines trace their origins back to a few Peugeots built a hundred years ago by a trio of racers, Jules Goux, Georges Boillot and Paolo Zuccarelli — and their engineer collaborator Ernest Henry.
The race cars they built had several variations to comply with changing regulations, but today only two examples of these pioneering cars exist. This is one of them, while the other has a secure position in a Florida collection.
The Lindley Bothwell Peugeot L45 has Read More
Here we offer the John Willment Automobiles Ltd. racing team’s Ford Galaxie 500 — the landmark car in which the late, great, hugely popular driver Jack Sears stood the racing record on its head and shattered those long years of Jaguar domination. The Galaxie was a 400-horsepower 7-liter “Lightweight,” built by NASCAR stock-car racing specialists Holman & Moody in Charlotte, NC. It would be the first of three destined for the British saloon car-racing scene.
We commend Gentleman Jack’s 1963 Read More
The latest in Ferrari’s illustrious line of rear-engine V8 GT cars, the 488 GTE made its competition debut in the 2016 Daytona 24 Hours. With one car each from SMP Racing, Risi Competizione and Scuderia Corsa, it was Scuderia Corsa — with the sister car to that offered here — which defied expectations to take an excellent 10th place overall and 4th in class, behind established GT class grandees Corvette Racing and Porsche.
Scuderia Corsa purchased a second 488 — Read More
The Porsche 917 K was the direct result of years of intense research. Although it employed the most modern concepts in automotive design, the new car was absolutely in keeping with Porsche tradition. The foundation of the new model was an incredibly lightweight aluminum space-frame chassis. Similarly, the suspension systems made extensive use of lightweight materials such as titanium and magnesium.
Glued to this frame was a striking, streamlined body made from thin fiberglass. Covered in NACA ducts and suspension-controlled Read More
The 1950s saw a surge in the popularity of small-displacement 4-cylinder engines. Few were as influential as the engine that powered Maserati’s 200S sports racer. The competition-proven Modena powerplant attracted significant interest from privateers running other makes, and the company was only too happy to sell engines to such concerns, paving the way for race cars like the Cooper- and Lotus-Maserati.
In 1959, an American driver, Tony Settember, purchased a 200S engine with the intention of using it in his Read More
While most GTAs were either supplied in Stradale form or subsequently upgraded to Corsa specification, chassis AR752675 was destined for competition from the outset.
Correspondence from the Alfa Romeo Museum confirms that the car was manufactured on September 8, 1965, and delivered to the renowned Autotecnica Conrero Team on August 31, 1966 — unusually, in right-hand-drive form.
One of the most celebrated privateers in Italy, Autotecnica Conrero was established in 1951 and quickly acquired a stellar reputation for tuning Alfa Read More


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Are you struggling to find time for personal relaxation amid your busy schedule? Despite the growing demands of daily tasks, it's essential to nurture your mind, the engine of your well-being.
This indirectly impacts your overall health, including physical, mental, and emotional well-being. Prioritizing self-care is a means of safeguarding your mental faculties, ensuring they operate optimally without disruption.
Self-care doesn't offer a precise mental health formula, but it involves making incremental adjustments to cultivate inner peace. How you navigate life's challenges and stressors determines your mental health journey. The following ten tips explore ways to nurture your mental well-being and integrate self-care into your routine.
Engaging in meditation promotes mental calm and physical relaxation. It effectively reduces anxiety and stress. Whether outdoors or indoors, you can choose your posture and focus on controlled breathing and relaxation.
Meditation also reduces inflammatory chemicals like cytokines, lowering stress, improving mood, and preventing depression.
Additionally, meditation enhances self-awareness and mental calm. Mantra meditation helps prevent memory loss. Various meditation types benefit mental health. Choose one to improve well-being.
2. SPENDING TIME WITH YOURSELF AND NATURE
Allocate time for respite, essential to rejuvenate from tasks. Acknowledge your contributions to family and friends, nurturing mental well-being. After arduous workdays, refrain from overexertion; embrace nature through evening strolls. Occasional repose beneath the open sky, gazing at clouds, calms the psyche. Essential for tranquility and vitality.
3. REWARDING YOURSELF
Whenever you attain a goal, regardless of its magnitude, it holds significance. Take the opportunity to acknowledge your accomplishments by either indulging in a well-deserved gift or savoring your preferred cuisine. Enhance the quality of your life by incorporating self-care practices into your daily routine. By doing so, you can experience an improved sense of well-being and sustain positive mental health.
4. DOING AN ACTIVITY YOU LOVE
Engage in a preferred activity for emotional solace and mental ease. Options include painting, dancing, writing, singing, cooking, or watching a film. Channel your imagination onto canvas, finding tranquility in the process.
Alternatively, sway to the music's rhythm, liberating your mind from concerns. Express your thoughts on paper for profound relaxation and inner serenity. This practice offers optimal stress relief and inner peace.
5. CUTTING YOURSELF OFF SOCIAL MEDIA FOR AT LEAST AN HOUR
Isn't it detrimental to incessantly stress one's eyes and mind on a smartphone? Presently, individuals dedicate over 10 hours to their mobile devices, resulting in adverse effects on mental well-being, particularly ocular health. Excessive mobile screen usage, whether for entertainment or socializing, necessitates occasional breaks to relax one's mind through soothing music playlists.
6. EATING A WELL BALANCED DIET
The correlation between dietary choices and emotional well-being is well-established. Optimal mental health necessitates a rich supply of essential nutrients for optimal bodily functions. A diet beneficial to both physical and mental health comprises leafy greens, diverse fruits, and seasonal varieties.
Limit excessive sugar and caffeine consumption to preserve your sleep pattern. Incorporate nuts, seeds, and oily fish for Vitamin D. Additionally, remember the invaluable elixir of life – water. It plays a pivotal role in promoting mental serenity and maintaining physical health.
Individuals may turn to alcohol as a means of coping with adversity or escaping challenges. However, this approach is not conducive to maintaining one's mental well-being.
Some individuals resort to alcohol to alter their emotional state or alleviate anxiety, but this results in fleeting effects and unpleasant withdrawal symptoms. When the drink wears off, it exerts a detrimental impact on both mental and physical health. Furthermore, the need for increased consumption to address the same issues ultimately jeopardizes one's peace of mind. To promote a sound mental state, it is advisable to consume alcohol in moderation, adhering to the recommended limit of 14 units per week for both men and women.
8. TALKING ABOUT YOUR FEELINGS
Discussing one's emotions with others can alleviate the burden of long-held thoughts, benefiting mental and physical well-being. This practice signifies a proactive approach to mental health care. Engaging in conversations can effectively address lingering concerns, with attentive listening serving as a stress-relief mechanism. Consequently, dialogue fosters tranquility and dispels intrusive thoughts, nurturing mental serenity.
9. SLEEPING ENOUGH
Getting adequate rest by retiring early is essential in order to rejuvenate mindfully after a long and tiring day. Insufficient sleep leads to fatigue, negatively impacting work productivity. Prioritizing ample sleep is crucial for maintaining optimal mental and physical well-being, enabling enhanced productivity.
10. READING YOUR FAVOURITE NOVEL OR MAGAZINE
Engage in leisurely reading to unwind from work-related stress. Retreat to your desk when feeling drained and immerse in a magazine for mental tranquility. Reading serves as a valuable respite from life's demands.
Self-care requires ongoing commitment, involving incremental habit adjustments within your daily routine. Prioritize well-being and allocate dedicated time for self-care activities.
Always bear in mind that your body and mind are invaluable assets. Caring for them enhances your physical, emotional, and mental health. Maintaining both is essential for a fulfilling life. Implement these straightforward tips to monitor your mental health and enhance your overall well-being.
So, what will you opt for today to nurture your peace of mind?

domain: psychology


Command Sergeant Major Daniel W. Arndt
Command Sergeant Major, LOGCAP Support Brigade (Photo by NA)
CSM Daniel W. Arndt assumed duties as the Command Sergeant Major of the LOGCAP Support Brigade in July 2018. He enlisted in the Army on January 4th, 1990, and attended Basic Training at Fort Sill, Oklahoma and Advanced Individual Training as a 75D (Personnel Records Specialist) at Fort Jackson, South Carolina
His initial assignment was as a Personnel Records Specialist at the 123d Army Reserve Command at Fort Benjamin Harrison, Indiana. He was promoted to Sergeant in 1992 and assigned as a Personnel Records Specialist with the 425th Personnel Service Company in Indianapolis, Indiana. While assigned there, he was activated and served in the DCSLOG, 123d Army Reserve Command to support mobilization and deactivation operations. He was promoted to Staff Sergeant in 1994 and assigned as the Personnel Management Supervisor, 5030th USARF School in Indianapolis. He then transferred to the 6035th Garrison Support Unit, Fort Benjamin Harrison serving as the Personnel Management Supervisor. His next assignment was as the Administrative NCO in the US Army Overseas Element-Korea. He was promoted to Sergeant First Class in 1999 and assigned as the Operations NCO in the 823rd AG Replacement Company, Indianapolis. He was then transferred to serve as the Budget Senior NCO in the Eighth United States Army Augmentation, Indianapolis. He was promoted to Master Sergeant in 2002 and assigned as the Resource Management Operations NCO, 21st Theater Support Command headquartered in Kaiserslautern, Germany. The unit was mobilized and deployed in support of Operation Enduring Freedom and Iraqi Freedom. Upon return he continued to serve with the 21st Theater Support Command until he transferred to Eighth Army (CONUS) located in Indianapolis. He was promoted to Sergeant Major in 2007 and served as the Senior Financial Operations Advisor with the 376th Financial Management Company located in Wausau, Wisconsin. He was then selected to serve as the Chief, Finance NCO at the 100th Division (Operational Support) located in Louisville, Kentucky. Upon reorganization of the unit he transferred to the 310th Sustainment Command (Expeditionary) located in Indianapolis serving as the G1 Sergeant Major. In 2010, he was selected and appointed to serve as the Command Sergeant Major for the 633rd Quartermaster Battalion in Sharonville, Ohio. He subsequently was assigned in 2014 as the Command Sergeant Major for the 718th Transportation Battalion located in Columbus, Ohio. In 2017, CSM Arndt was transferred and activated to serve as the Command Sergeant Major with the 497th Combat Sustainment Support Battalion located in Salem, Virginia, in support of Atlantic Resolve in Eastern European. Upon completion of the deployment, CSM Arndt was selected in 2018 to serve as the Command Sergeant Major for the LOGCAP Support Brigade.
CSM Arndt’s military education includes the Personnel Records Specialist Course (Distinguished Honor Graduate), Primary Leadership Development Course, Basic Noncommissioned Officer Course, Advanced Noncommissioned Officer Course (Honor Graduate), Accounting Specialist Course (Honor Graduate), Planning, Programming, Budgeting and Execution Systems Course, Federal Appropriations Law, Additional Duty Safety Officer Course, Commander’s Safety Course, Sergeants Major Course, Financial Management Leader’s Preparatory Course, Resource Management Tactical Course, Deployed Operations Resource Management Course, and Command Sergeant’s Major Course. CSM Arndt’s civilian education includes a Bachelor of Science degree in Music Education from Ball State University in Muncie, Indiana. He also earned a Master of Arts Degree in Music from Ball State University
CSM Arndt’s awards and decorations include the Meritorious Service Medal with 3 Bronze Oak Leaf Clusters, Army Commendation Medal with 4 Bronze Oak Leaf Clusters, Army Achievement Medal with 1 Silver Oak Leaf Cluster, Army Reserve Components Achievement Medal with 1 Silver and 3 Bronze Oak Leaf Clusters, National Defense Service Medal with Bronze Service Star, Global War on Terrorism Service Medal, Korean Defense Service Medal, Military Outstanding Volunteer Service Medal, Armed Forces Reserve Medal with Silver Hourglass M Device and numeral 2, Noncommissioned Officers Professional Development Ribbon with 5 affixed, Army Service Ribbon, Overseas Service Ribbon, and the Army Reserve Component Overseas Training Ribbon with 8 affixed. CSM Daniel Arndt is married and they have three children.


text:
At the age of nineteen Nica Galas published her first book, the autobiographical tome Falling into the Sea which chronicled her short and torrid love affair among the hot beaches and lemon trees in the Gulf of Naples. The breathtaking story opens with Nica and her girlfriends picking bunches of jasmine flower for boys while they cliff-jumped into the sea. An innocent first kiss erupts into an ardent summer entanglement which is cut short one moonlit night when her lover leaps into the dark abyss never to surface, leaving Nica naked on the cliffs screaming his name.
This scent is sunshine in a bottle. Wear on cloudy days to invoke the ardor of summer.
Imaginary Authors offers wildly unique fragrances born from the concept of scent as art and art as provocation. Like a good book, these scents are meant to inspire you. In these bottles are layered narratives that are sure to generate stirring conversation, fragrances that might be capable of changing the course of your own personal story. Each Imaginary Authors fragrance follows a compelling storyline peppered with intriguing twists.

domain: library


text:
The apartment hotel is located in the heart of the promenade opposite the Playa de Aro, Bernat Cavall and marina. This town offers shopping, culture and leisure activities, just few metres from the hotel. Links to the public transport network are around 2||These apartments are an annex to the Hotel Arona. They are independent units but guests can use all services of the hotel. Renovated in 2010, the air-conditioned property comprises 25 apartments and welcomes guests in a lobby with 24-hour reception and ch||All apartments are equipped with a shower, double bed, satellite/cable TV, Internet access, air conditioning, central heating and a terrace. The kitchens/kitchenettes are fitted with a fridge, cooker and microwave.||In the outdoor swimming pool guests can enjoy a relaxed atmosphere amidst pines. Younger guests will be entertained in the children's swimming area. Sun loungers and parasols are laid out for use. A wide range of water sports are possible for additional f||Buffets are served at all meal times.
Hotel Apartamentos Delfin on map

domain: travel


To avoid getting in the rut of similar arrangements, a songwriter should take another look at the parts of a song. Without variety, songs can become boring and predictable. Here is a quick refresher on the different parts of a song.
- Verses. Verses are the parts of a song that tell the story or explain the meaning. They usually sound alike but have different words. Songwriters keep the verses alike to build structure in the song. Typical songs have two or three verses, but some have more.
- Chorus. Sometimes called the refrain, the chorus is a song’s focal point. It is the part of a song that repeats itself. It often contains a hook that gets people to remember the song. A song’s chorus usually appears two or three times, often several times.
- Pre-Chorus. A pre-chorus is the versatile part of a song that comes right before the chorus. Often used to build up the chorus, the pre-chorus sounds different from the verses or chorus. The pre-chorus verses can be different or the same whenever the part appears in the song.
- Post-Chorus. The post-chorus directly follows the chorus. It sounds different from the chorus, but it may retain the same power level. Singers often use the post-chorus to repeat the line at the end of their chorus. Some musicians use an instrumental piece as the post-chorus.
- Bridge. A bridge is the change-up part of a song. Almost like a second style of verse, the bridge is different from other song parts. Songs usually have just one bridge, although creative songwriters may add more than one. Usually, each bridge sounds different.
- Musical Solo. A musical solo is the part of a song that features an instrumental solo. Sometimes the musical solo replaces a verse or chorus part. The most interesting musical solos have a life of their own, while still fitting the song.
- Intro. The intro gets people’s attention. It can be the verse or chorus played in an unusual way or something completely different, like a part that doesn’t appear anywhere else in the song.
- Extro. Sometimes called the outtro, the extro is similar to the intro. Of course, it appears at the end of the song. It usually contains a few lines of the chorus that slows down at the end.
- Breakdown. A breakdown leaves something out. Usually, it is a verse or chorus with less instrumentation. Sometimes a breakdown and a bridge are the same part. Songwriters use breakdowns to lower a song’s energy before building it back up.


The Government is taking steps towards enforcing age verification for the use of online pornography in the UK from next spring.
Under new powers contained in the Digital Economy Act, which passed through Parliament earlier this year, a regulator will be able to block porn websites that fail to show they are denying access to under-18s, for instance by demanding credit card details.
The move has been welcomed by internet safety charity Childnet, which said watching online porn could be 'deeply damaging' to young people.
Childnet chief executive Will Gardner said: "Protecting children from exposure, including accidental exposure, to adult content is incredibly important, given the effect it can have on young people.
"Steps like this to help restrict access, alongside the provision of free parental controls and education, are key."
However, the NSPCC said that the new measures did not go far enough and there was a need for additional protection for youngsters on social media.
They would like to see sites such as Twitter, Facebook and Instagram set up 'safe accounts' where children can interact peers safely.
Sandra McNair, NSPCC Midlands regional head of service, said: "At the NSPCC we have long stressed the deeply damaging effect pornography has on young people's behaviour. It warps their understanding of consent, distorts their views of body image and can be downright dangerous when it comes to learning about sexual health.
"This move is a first step. Government must now grasp the nettle and take further action to protect our children from online dangers. Enforcing the proper regulation of social networks is a matter of urgency.
"Some social networks have designed their platforms with child safety in mind, others have not. Some are good at taking action when harmful content is reported, others are not.
"Each network has their own rules for handling inappropriate content or abusive behaviour on their platforms. This leads to inconsistencies in keeping children safe, and ultimately means social networks are marking their own homework. We've had enough and children have had enough.
"Social networks must be made to offer Safe Accounts to under 18s. These will have high privacy settings as default, location settings locked off, offer control over who follows you, and child-friendly reporting buttons that are easy to find and easy to read.
"Groomer and bully alerts must also be built into these accounts and automatically flag behaviours to moderators when children are targeted.
"Proper regulation of social networks will make the internet a better place for young people by protecting and empowering them. Children must be as safe online as they are offline."
Parents in Stoke-on-Trent say the dangers their sons and daughters face online was one of their biggest concerns.
Dad Jim Doolan, of Stoke, said: "There is a lot on the internet that children shouldn't be seeing and I have heard the stories of children swapping photos they shouldn't have at school. It is a huge problem.
"They can access this kind of material far too easily and that shouldn't happen. There is no easy fix but the Government should do more."
Karren Key, aged 51, from Stoke, said: "I have nieces and nephews who are young and I do worry. They are good and do what their parents tell them but I know that there are a lot of families that are not like that.
"There is a lot on the internet that is easily accessible. I think that the parents should also be doing more to stop their children accessing that material.
"A lot has changed and not for the better. I think it needs to be a joint effort between parents and the Government to keep children safe online."
Under the Digital Economy Act, adult sites based anywhere in the world will be required to show that they are verifying users' age. Failure to do so could result in a bar on credit card payments from the UK or a block from being carried by UK internet service providers.


text:
After accidentally stumbling into his uncle's mysterious "tanning bed", Adam learns the answer to all of his problems - multiple Adams.
With his new collection of clones, Adam is hopping on one wild summer ride with an epic splash.
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As part of a multi-platform experience, the games seen in the episodes will be released through apps and online from Nickelodeon. If I could describe these two in one word, it would be obnoxious. Explosions, unfunny punchlines, using Hudson as a joke dispenser and being "OH YEAH SO FUNNY AND RANDEM XDDDD" doesn't translate to comedy. I could go on, but after watching about two episodes and stopping after that, means that you have utterly FAILED at captivating my attention. Releasing Drake & Josh, i Carly and more, I expected something better from him.
The show WITS Academy was such a disaster, that Nickelodeon immediately ordered the show to stop production, before it hurt the company. But when Sam & Cat aired, I realized that this network has officially lost it in the sitcom department.
Another weapon in the Unreveal arsenal is the end-of-episode cutoff.
A special case of Unreveal is when we think that the info withheld in an Unreveal earlier in the episode is finally going to be revealed now... A last type of Unreveal is the "you know the rest" gag: A character is giving historical information to another character, and ends by saying "you know the rest," even though the viewer does not.
Usually done for comedic effect, since it's a good way to create outrageous backstory without having to make it fit continuity.

domain: entertainment


text:
|Nearest city||Lewisburg, Pennsylvania|
|Area||3 acres (1.2 ha)|
|Architectural style||Octagon Mode|
|NRHP reference #||74001799 |
|Added to NRHP||12 February 1974|
|Designated PHMC||May 08, 1969|
Sodom Schoolhouse is a historic octagonal school in West Chillisquaque Township, Northumberland County, Pennsylvania, United States reportedly built about 1812, 1835, or 1836 and used until 1915. It is located in a rural area on Pennsylvania Route 45 near several Scotch-Irish communities: the "small group of houses" formerly known as Sodom, which was about a mile east of the hamlet of Montandon, and about 3 miles east of a small town, Lewisburg.
The eight-sided single story school was built of limestone quarried nearby, has a single chimney in the center of the roof, seven windows, and a single door on the south side facing the road. A vestibule was once attached where students hung their coats. The inside was painted slate grey, and a wood-burning stove stood in the center. On the north wall was a blackboard, with a 30-foot long, 10-foot wide, 8–10-inch high platform for the teacher. The teacher's chair and desk were painted red. Two recitation benches faced the platform. Six long rough desks were placed parallel to the walls and two more were placed in the center of the room. Students within a three-mile radius attended, sometimes as many as 100 at one time, but usually only 40–60 students attended.
The name of the school may come from the "Sodom Tavern" which did business in Montandon 1832–1855, or from the hamlet of Sodom which was named by Lot Carson, the owner of another tavern, who died by falling down a well while drunk. Carson may have donated much of the building material to the school. Until 1858 the school building was also used as a Methodist Church on Sundays. It was also used for political meetings and elections.
A cupola and bell once stood above the front door. Stories, or perhaps legends, say that the building of school was delayed by the start of the War of 1812 when the builders went off to war, and not completed until their return from the war. The hamlets of Montandon and Sodom, however, were not established until the 1830s and 1835 is a more commonly accepted construction date.
Several similar octagonal schools were built in Pennsylvania, especially in Chester County and rural Philadelphia County, for example the Birmingham Friends Octagonal School (1819) and the Hood Octagonal School (1841). One source suggests that octagonal schools are related to a Quaker educational movement that started about 1800 in England as the Industrial Revolution was beginning. Clapham School, built 1810 in or near London, may have been one of the first octagonal schools.
- "National Register Information System". National Register of Historic Places. National Park Service. 13 March 2009.
- "PHMC Historical Markers". Historical Marker Database. Pennsylvania Historical & Museum Commission. Retrieved 20 December 2013.
- Pennsylvania Register of Historic Sites and Landmarks, 1973, NRHP Nomination Form for Sodom Schoolhouse Enter "public" for ID and "public" for password to access the site.
- Pennsylvania Historical Marker Program, searchable database, search "Sodom School."
- History of Northumberland County, Pennsylvania, Herbert C. Bell, editor, Brown, Runk and Company, Chicago, 1891. See pages 720 and 724.
- Historic Educational Resources of Pennsylvania, Dominic Vitiello, Pennsylvania Historical and Museum Commission, 2007. See page 20.
- Sodom School loses belltower, Standard Journal, May 2008, Montandon Community Days, excerpted from the 11 October 1977 issue of Here & Now. Accessed 6 February 2011.
- Pennsylvania Historic and Museums Commission, undated, Historic Structure Report Enter "public" for ID and "public" for password to access the site.

domain: geography


text:
501650 - Library Services Specialist II, Circulation/Access Services
501650 - Library Services Specialist II, Circulation/Access Services
Classificaiton: Library Services Specialist II
Department: Pollak Library Administration
Sub-Division: Vice President, Academic Affairs
Salary Range: $3,246 - $5,983 per month
Appointment Type: Ongoing
Time Base: Full-Time
Work Schedule: Monday - Friday, 8:00 AM - 5:00 PM
Standing on 241 acres at the heart of Southern California, the university was founded in 1957 and has grown into a population of over 39,000 students. As Titans, we believe that diverse perspectives deepen our understanding. We are committed to giving students the support they need to graduate, while responding to California’s revolving work force needs. At California State University, Fullerton we strive for continual improvement of students, staff, faculty and administrators through orientations, training programs and professional development opportunities. As part of the Titan Community, you have access to many campus facilities and services including but not limited to the Grand Central Art Center in Santa Ana, CSUF Garden Grove Center, Fullerton Arboretum, cultural events and performances in the Clayes Performing Arts Center, Cal State Fullerton Athletics sports events, Titan Recreation Center, and the Employee Wellness Program.
It is an exciting time to join Cal State Fullerton as we are an in demand comprehensive University that is driven to shape the future of education and foster a vibrant community of diverse students, faculty, staff and administrators who uphold values of inclusive excellence, free speech, and an environment free from discrimination. We are continuously seeking individuals from a variety of career disciplines that share in the University's mission and core values. We warmly welcome you to consider joining the Titan Community where minds expand and opportunities flourish.
About the Position:
The Pollak Library Administration Office aims to become a model library, nationally recognized for innovative spaces, collections, services, tools, and programs that enable academic success of our students; promote information literacy skills; fulfill the needs of our academic programs and scholarly activities; facilitate and encourage the systematic and serendipitous acquisition of knowledge; invite collaboration; and help interconnect its vibrant and diverse community of learners and scholars. We are searching for an exceptional individual to join our team as a Library Services Specialist II, Circulation/Access Services. The ideal candidate in this role should have a positive attitude and an active, energetic mind that is characterized by highly ethical practices and a commitment to diversity, openness, flexibility, integrity, and kindness.
Under the general direction of an assigned Public Services Coordinator, the Library Services Specialist II oversees functional operations at various public desks in the Pollak Library and operations critical to the smooth delivery of library user services in the Public Services Unit. Directs the work of between two to ten student assistants to ensure an efficient workflow and resolves difficult desk situations. Depending on the hours or location, responsible for opening and/or closing the library. Handles short term or longer term projects and responsibilities related to Public Services including student employee oversight/work coordination and record keeping. Other duties as assigned.
High School diploma or the equivalent and a minimum of two years of related library or clerical experience. Full proficiency in all technical aspects of work assignments including a thorough knowledge of functional area policies and procedures and applicable work methods. General knowledge of library collection organization and classification scheme, as well as the ability to interpret bibliographic records. Ability to interpret library unit’s policies and procedures and apply them accurately in performing work functions. Ability to evaluate procedures and recommend changes. Working knowledge of campus and library policies and practices associated with the ethical use of and access to library and on-line resources. Basic knowledge of national standards and guidelines pertaining to libraries, including working knowledge of campus standards pertaining to copyright and intellectual property protection with the ability to source and apply such policies and standards to avoid potential violations. Full proficiency in the use of automated library systems and subsystems pertaining to the functional work area. Ability to fully utilize standard and non-standard features of various on-line resources and standard desktop software packages, such as word processing and spreadsheets, to perform technical work and assist patrons. Demonstrated problem solving and research skills to address standard and non-standard work problems. General knowledge of library accounting and budget procedures, including the ability to perform arithmetic operations to track and monitor vendor accounts and budgets. Demonstrated ability to compile and present information in an organized manner. Possession of effective communication and interpretive skills to assist in resolving patron problems and complaints, assess patron information needs, and orient and guide patrons in use of library resources. Ability to effectively provide lead work direction and training to student workers, as well as an understanding of employment and payroll procedures related to student workers.
A background check (including a criminal records check) must be completed satisfactorily and is required for employment. CSU will make a conditional offer of employment, which may be rescinded if the background check reveals disqualifying information, and/or it is discovered that the candidate knowingly withheld or falsified information. Failure to satisfactorily complete the background check may affect the continued employment of a current CSU employee who was conditionally offered the position.
Recent experience in working in an academic library environment. Demonstrated ability to make good decisions when interpreting policies and explaining procedures, as well as the ability to be diplomatic and negotiate disputes. Ability to work independently
Experience directing the work of others.
Special Working Conditions:
Notice of Non-Discrimination on the Basis of Gender or Sex and Contact Information for Title IX Coordinator
California State University, Fullerton celebrates all forms of diversity and is deeply committed to fostering an inclusive environment within which students, staff, administrators and faculty thrive. Individuals interested in advancing the University’s strategic diversity goals are strongly encouraged to apply. Reasonable accommodations will be provided for qualified applicants with disabilities who self-disclose.
Multiple positions may be hired from this recruitment based on the strength of the applicant pool.
If you are applying for a staff position, please note that you are not eligible to work concurrently in a staff position and an Academic Student position such as Graduate Assistant, Teaching Associate, Instructional Student Assistant or a Student Assistant position.
Regular attendance is considered an essential job function.
Employee/applicant who submits an application for a position may be required to successfully complete job related performance test(s) as part of the selection process.
Online application/resume must be received by electronic submission on the final filing date by 9:00 PM (Pacific Standard Time)/midnight (Eastern Standard Time). Applicants who fail to complete all sections of the online application form will be disqualified from consideration.
California State University, Fullerton is not a sponsoring agency for staff or management positions (i.e. H1-B Visas).
Application Deadline: Jul 29, 2021 (9:00 PM)
Apply online at: https://careers.pageuppeople.com/873/fl/en-us/job/501650/501650-library-services-specialist-ii-circulationaccess-services


text:
The Sam Houston women’s volleyball team is ready to kick off a new season starting Tuesday, Feb. 2, when the Bearkats take on the Central Arkansas University Sugar Bears. The Bearkats are looking to build off the successes from last season to take on the entire Southland Conference and come out on top.
Last season, the Bearkats came in second overall in the Southland Conference with a record of 12-4, 19-14 overall, finishing behind Stephen F. Austin State University’s undefeated season. The Ladyjacks placement may be a source of motivation for the volleyball team, but according to head coach Brenda Gray, the team is focused more on the game they are playing than who they are playing.
With a large number of last season’s team returning for the season, the championship title is well within reach for the Bearkats. Senior outside hitter, Ashley Lewis, returns after having a season of 482 kills and 364 digs. Including having double-digit kills in 28 of her 33 matches.
Junior outside hitter, Breanne Chausse, also looks to make an impact this season after recording 414 kills last season. Chausse also finished eighth in the conference for kills per set with an average of 3.09.
The Sam Houston women’s volleyball team also features several new faces, as five freshman players have been added to the team after last season.
Notably, the Bearkats will face off against reigning Southland Conference champions, the Ladyjacks, on March 25.
The Bearkats will compete this season in the Southland Conference Tournament to attempt to take home the championship they were so close to a year ago. The Southland Conference Tournament will take place on April 1-3 in Corpus Christi.
Up next, the Bearkats will host Northwestern State University at 6:30 p.m. on Feb. 4.

domain: news