KR20070007700A - Power factor adjustment device - Google Patents

Abstract

A power factor adjustment device is provided to adjust an optimum power factor by selectively controlling opening/closing a condenser of a large capacitance and a condenser of a small capacitance. A power computing unit(6) computes an active power value and a reactive power value based on a voltage value and a current value in an electric system. A control signal generating unit selectively outputs a first control signal and a second control signal. A first control unit(8) outputs a first opening/closing signal to close one of at least two first condensers(10) connected to the electric system via a first opening/closing member and open the other first condenser. A second control unit(9) outputs a second opening/closing signal to close one of second condensers(12) connected to the electric system via a second opening/closing member and open the other second condenser.

Description

Power factor adjustment device {POWER FACTOR ADJUSTMENT DEVICE}

BRIEF DESCRIPTION OF THE DRAWINGS The block diagram which shows the structure of the water substation system using the power factor adjustment apparatus 1 in Embodiment 1 of this invention.

Fig. 2 is a block diagram showing the structure of the power calculating section 6 according to the first embodiment of the present invention.

Fig. 3 is a block diagram showing the configuration of the control unit selection circuit 7 according to the first embodiment of the present invention.

4 is a block diagram showing the configuration of the control unit selection circuit 70 according to the second embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration of a control unit selection circuit 700 in accordance with the third exemplary embodiment of the present invention. FIG.

Fig. 6 is a block diagram showing the structure of a water substation system using the power factor adjustment device 1 according to the fourth embodiment of the invention.

Fig. 7 is a block diagram showing the structure of the control unit selection circuit 17 according to the fourth embodiment of the present invention.

[Description of the code]

1 power factor adjuster

2 transformer

3 load side busbar

4 Instrument transformer

5 current transformer

6 Power calculation unit which is a power calculation means

7 control unit selection circuit serving as a control signal generator

8 Main control part which is a 1st control means

9 Sub-control unit as second control means

10 Main capacitor as the first capacitor

11 opening and closing part which is the first opening and shutting means

12 Second Capacitor

13 opening and closing part which is 2nd opening and shutting means

14 transformer

15 load

16 self power systems

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power factor adjustment apparatus for controlling opening and closing of a plurality of capacitors for improving power factor, connected to a load side busbar of a transformer for water substation, such as a water substation system, to improve the power factor.

In the conventional power factor adjustment device, the opening and closing of the power factor correction capacitor is controlled based on the magnitude relationship between the first and second reference values for determining the load of the active power and the effective power value (see Patent Document 1, for example). . That is, when the effective power value is relatively small (when the effective power value is between the first reference value and the second reference value), the insertion of a large capacity capacitor is prohibited and the small capacity capacitor is closed to adjust the power factor. there was.

 [Patent Document 1] Japanese Patent Laid-Open No. 8-336234 (2 pages, Fig. 2)

As described above, in the conventional power factor adjusting device, when a large capacity capacitor and a small capacity capacitor are mounted on the load side busbar of the transformer for water displacement, and the effective power value is small (the effective power value is between the first reference value and the second reference value) ), The power factor is adjusted by prohibiting the introduction of a large capacity capacitor and closing the small capacity capacitor. This is a control under the precondition that the reactive power value is small when the effective power value is small. However, for example, when a self-generating system is installed in the load side busbar of a transformer for water-supply transformers, and the power supplied by the self-generating system is used together with the power supplied from the power company, the power supply from the electric power company is determined to have an effective power value. At the same time, the reactive power value may increase. If such a conventional power factor adjustment device is applied under such conditions, there is a problem that the power factor is greatly delayed so that transmission loss increases and an improvement effect cannot be obtained.

This invention is made | formed in order to solve the above subjects, and an object of this invention is to provide the power factor adjustment apparatus which can adjust to an optimal power factor irrespective of the magnitude | size of an effective power value and a reactive power value.

The power factor adjustment device according to the present invention includes power calculation means for calculating an effective power value and a reactive power value based on a voltage value and a current value in a power system, and when the effective power value is equal to or larger than a first predetermined reference value or the active power value. Outputs a first control signal when the value is less than the first reference value and is greater than or equal to the predetermined second reference value, and the reactive power value is greater than or equal to the predetermined third reference value, and the effective power value is less than or equal to the first reference value and greater than or equal to the second reference value; And control signal generation means for outputting a second control signal for the people when the reactive power value is less than the third reference value, and through the first opening and closing means to the power system based on the first control signal and the reactive power value. The at least two first capacitors connected are closed by selectively controlling the first opening / closing means and are not closed. A first control means for outputting a first open / close signal that selectively controls the first condenser by selectively controlling the first open / close means, and second open / close means in the power system based on the second control signal and the reactive power value. At least one second condenser connected through the second condenser having a smaller capacity than the first condenser, and selectively closing the second opening / closing means, and closing the second condenser that is not closed. It is provided with the 2nd control means which outputs the 2nd open / close signal which controls and individualizes.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is concretely demonstrated based on drawing which shows embodiment. In addition, embodiment demonstrates the case where the power factor adjustment apparatus which concerns on this invention is applied to a water substation system, and the opening / closing of the multiple power condenser for power factor improvement connected to the load side busbar of the water-transformation transformer is demonstrated as an example.

Embodiment 1.

1 is a block diagram showing a configuration of a water substation system to which the power factor adjustment device 1 is applied in Embodiment 1 of the present invention. In FIG. 1, the current transformer 4 is provided in the load side busbar 3 of the transformer 2, and the line current value of each phase of the load side busbar 3 is measured. Moreover, the instrument transformer 5 is connected to the load side bus line 3, and the voltage value of each phase of the load side bus line 3 is measured. The measured line current value and the voltage value of each phase are transmitted to the power calculating section 6 which is a power calculating means of the power factor adjusting apparatus 1, and the effective power value P and the reactive power value Q are calculated. The effective power value P is transmitted to the control unit selection circuit 7 which is a control signal generating means, and the reactive power value Q is the control unit selection circuit 7, the main control unit 8 which is the first control means, and the sub-control unit which is the second control means. Each is delivered to (9). The control unit selection circuit 7 includes the first power 7 and the second control signal based on the effective power P and the reactive power Q, and the first to third reference values. The stationary portion 7b is transmitted to the main controller 8 and the sub controller 9, respectively.

The main controller 8 has N main capacitors Cm as first capacitors based on the reactive power value Q transmitted from the power calculating section 6 and the first determination value 7a transmitted from the control section selection circuit 7. The B signal, which is the first open / close signal for closing (10), and the b signal, the first open / close signal for closing, are transmitted to the main open / close unit 11, which is the first open / close means. In Embodiment 1, it is assumed that the capacities of the main capacitors 10 are all the same. The sub-control unit 9 is based on the reactive power value Q transmitted from the power calculating unit 6 and the second determination value 7b transmitted from the control unit selection circuit 7. The A signal, which is the second open / close signal for closing (12), and the a signal, which is the second open / close signal for individualizing, are transmitted to the sub-opening / closing portion 13 that is the second opening / closing means. In Embodiment 1, it is assumed that the capacities of the subcapacitors 12 are all the same, and the sum of the capacities of the subcapacitors 12 is smaller than the capacities of one main capacitor 10. The main opening and closing part 11 closes the main capacitor 10 corresponding to the input B signal, and opens the main capacitor 10 corresponding to the b signal. The sub-opening unit 13 closes the sub-capacitor 12 corresponding to the input A signal, and opens the sub-capacitor 12 corresponding to the a signal. In addition, the load side bus bar 3 supplies electric power to the load 15 through the transformer 14. In addition, the self-generating system 16 is connected in parallel to the load side bus bar 3, and supplies electric power to the load 15 via the transformer 14.

Next, the operation of the water substation system shown in FIG. 1 will be described. Each of the current transformer 4 and the instrument transformer 5 provided in the load side bus line 3 of the transformer 2 sums the line current and voltage of each phase, and supplies the line current value 4a and the voltage value 5a to each other. It transfers to the calculating part 6. The structure of the electric power calculating part 6 is shown in FIG. In Fig. 2, the voltage phase shifter 61 delays the phase of the voltage by? / 2 in time. The reactive power unit 62 calculates reactive power, and the active power unit 63 calculates active power. Multiplication blocks 64 and 65 multiply inputs. The addition blocks 66 and 67 add the outputs of the multiplication blocks 64 and 65, respectively.

The operation of the power calculating section 6 will be described. The voltage value 5a of each phase transmitted to the power calculating section 6 is transmitted to the voltage phaser 61, and the phase is delayed by [pi] / 2. The voltage value of each phase whose phase is delayed is transmitted to the multiplication block 64 of the reactive power unit 62. The multiplication block 64 multiplies the voltage value of each phase whose phase is delayed by the line current value 4a of each phase. The result of the multiplication in the multiplication block 64 is transmitted to the addition block 66, and is added to output the effective value of the reactive power, that is, the reactive power value Q, collectively in three phases. On the other hand, the voltage value 5a of each phase delivered to the power calculating section 6 is directly transmitted to the multiplication block 65 of the effective power unit 63 without passing through the voltage abnormalizer 61. The multiplication block 65 multiplies the voltage value 5a of each phase by the line current value 4a of each phase. The result of multiplication in the multiplication block 65 is transmitted to the addition block 67, and is added to output the effective value of active power, that is, the effective power value P, collectively in three phases.

The effective power value P and the reactive power value Q output from the power calculating section 6 are both delivered to the control section selection circuit 7 as shown in FIG. 1. The structure of the control part selection circuit 7 is shown in FIG. In FIG. 3, the 1st reference value setting part 71 sets the 1st reference value T1 of the light load detection of active power to a predetermined value, and transmits it to the comparator 74. FIG. The second reference value setting unit 72 sets the second reference value T2 of light load detection of the active power to a predetermined value and transmits it to the comparator 75. The third reference value setting unit 73 sets the third reference value T3 of the light load detection of the reactive power to a predetermined value and transmits it to the comparator 76. Comparators 74-76 compare the inputs and output logic signals 1 or 0. The logic circuits 77 and 78 output logic signals 1 or 0 as the first determination value 7a and the second determination value 7b, respectively, in accordance with a predetermined logic expression based on the input.

The operation of the control section selection circuit 7 will be described. The comparator 74 compares and determines the magnitude of the first reference value T1 and the effective power value P, and compares the logic signal 1 when the effective power value P is greater than or equal to the first reference value T1, and the logic signal when the effective power value P is less than the first reference value T1. Print zeros each. The comparator 75 compares and determines the magnitude of the second reference value T2 and the effective power value P, and compares the logic signal 1 when the effective power value P is greater than or equal to the second reference value T2, and the logic signal when the effective power value P is less than the second reference value T2. Print zeros each. The comparator 76 compares and determines the magnitude of the third reference value T3 and the reactive power value Q. The comparator 76 makes a logic signal 1 when the reactive power value Q is greater than or equal to the third reference value T3 and a logic signal when the reactive power value Q is less than the third reference value T3. Print zeros each. The logic circuit 77 has an output signal of the comparator 74 of 0, an output signal of the comparator 75 of 1, an output signal of the comparator 76 of 1, or an output signal of the comparator 74. When 1 is 1, the logic signal 1 is output as the first determination value 7a, and when other conditions, the logic signal 0 is output as the first determination value 7a. In the logic circuit 78, when the output signal of the comparator 74 is 0, the output signal of the comparator 75 is 1, and the output signal of the comparator 76 is 0, the logic signal 1 is determined as the second determination value ( 7b), the logic signal 0 is output as the second determination value 7b under other conditions.

In FIG. 1, the main control part 8 has previously existed beforehand the value of the reactive power value Q transmitted from the power calculating part 6, when the 1st determination value 7a transmitted from the control part selection circuit 7 is 1; N of the N main capacitors 10 connected to the load side busbar 3 such that the power factor is equal to or higher than the target power factor, that is, the power factor becomes 1 or the leading power factor based on the power capacities of the N main capacitors 10 The B signal for closing the dog is output to the main opening and closing part 11. On the other hand, for the remaining (N-n) main capacitors 10, b signals for individualizing them are outputted to the main opening / closing unit 11. Moreover, when the 1st determination value 7a is 0, the b signal is output to the main opening-closing part 11 with respect to all N main capacitors 10, and all the main capacitors 10 are individualized. The sub-control unit 9, when the second determination value 7b transmitted from the control unit selection circuit 7 is 1, the value of the reactive power value Q transmitted from the power calculating unit 6, and the M sub-capacitors existing in advance. Based on the electric power capacity of (12), the A-switching part which closes the A signal which closes m of M subcapacitors 12 connected to the load side busbar 3 so that it may become more than the target power factor, ie, the power factor becomes 1 or more ( 13). On the other hand, with respect to the remaining (M-m) subcapacitors 12, a signal that modifies these is output to the sub-switching unit 13. Moreover, when the 2nd determination value 7b is 0, the a signal is output to the opening-and-closing part 13 with respect to all M subcapacitors 12, and all the subcapacitors 12 are individualized.

The main opening / closing unit 11 closes the desired n main capacitors 10 by turning on a switch installed in the main capacitor 10 corresponding to the input B signal, and is installed in the main capacitor 10 corresponding to the input b signal. By turning off the switch, the desired (Nn) main capacitors 10 are individualized. In addition, the sub-switching unit 13 closes the desired m sub-capacitors 12 by turning on a switch provided in the sub-capacitor 12 corresponding to the input A signal, and the sub-capacitor 12 corresponding to the input a signal. The desired (Mm) sub-capacitors 12 are individualized by turning off the switches installed in the switches.

In Embodiment 1, it is assumed that T1 to T3 set in the first to third reference value setting units described above are determined by prior measurement using a power meter or the like. For example, T1 measures and sets the effective power value Pd in the state where the self-power generation system 16 is operating during the day and the active power value Pn in the state where the self-generation system 16 is stopped at night, respectively. Specifically, it is assumed that Pn <T1 <Pd. In addition, T2 measures and sets the active power value Ph of a holiday, and specifically, sets it to Ph <T2 <Pn. In addition, T3 measures and sets the reactive power value Qd when the self-power generation system 16 is operating during the day and the reactive power value Qn when the self-generation system 16 is stopped at night, respectively. Specifically, Qn <T3 <Qd.

P로 되기 때문에 비교기(74)의 출력이 1로 되고, 따라서 논리 회로(77)의 출력이 1로 이고, 또한 논리 회로(78)의 출력이 0으로 된다. 이 경우, 주제어부(8)에 있어서는 무효 전력치 Q에 따라서 주개폐부(11)에 의하여 전력 용량이 큰 주콘덴서(10)를 개폐 제어하므로, 지연 역률로 되는 것을 피할 수 있다. In the power factor adjustment apparatus 1 configured as described above, in the state where the self-power generation system 16 is stopped in the weekday, the effective power value P and the reactive power value Q become larger together. Active power P is T1

Since it becomes P, the output of the comparator 74 becomes 1, therefore, the output of the logic circuit 77 becomes 1, and the output of the logic circuit 78 becomes zero. In this case, in the main control part 8, since the main capacitor 10 having a large power capacity is opened and closed by the main switch 11 according to the reactive power value Q, the delay power factor can be avoided.

P < T1 또한 T3

Q가 성립하고, 비교기(74)의 출력이 0이면서 비교기(75)의 출력이 1이면서 비교기(76)의 출력이 1로 되고, 따라서 논리 회로(77)의 출력이 1이면서 논리 회로(78)의 출력이 0으로 된다. 이 경우, 주제어부(8)에 있어서 무효 전력치 Q에 따라서, 주개폐부(11)에 의하여 전력 용량이 큰 주콘덴서(10)를 개폐 제어한다. 즉 이 경우는 부콘덴서(12)를 사용하지 않고, 주콘덴서(10)를 사용한다. 이로 인해, 큰 무효 전력치 Q에 대하여 용량이 큰 주콘덴서(10)를 사용하므로, 지연 역률로 되는 것을 피할 수 있다.In the state where the self-power generation system 16 is operated during the weekday, the effective power value P decreases in consideration of the active power supplied by the self-power generation system 16. Q increases. That is, T2 for the active power value P and the reactive power value Q

P <T1 also T3

Q is established, the output of the comparator 74 is 0, the output of the comparator 75 is 1, and the output of the comparator 76 is 1, thus the output of the logic circuit 77 is 1 while the logic circuit 78 Outputs zero. In this case, the main control unit 8 controls the main capacitor 10 having a large power capacity to open and close according to the reactive power value Q. That is, in this case, the main capacitor 10 is used instead of the sub capacitor 12. For this reason, since the main capacitor 10 with a large capacity is used for the large reactive power value Q, it becomes possible to avoid becoming a delay power factor.

P < T1 또한 Q < T3 이 성립하고, 비교기(74)의 출력이 0이면서 비교기(75)의 출력이 1이고, 또한 비교기(76)의 출력이 0으로 되고, 따라서 논리 회로(77)의 출력이 0이면서 논리 회로(78)의 출력이 1로 된다. 이 경우, 부제어부(9)에 있어서 무효 전력치 Q에 따라서 부개폐부(13)에 의하여 전력 용량이 작은 부콘덴서(12)를 개폐 제어함으로써, 지연 역률로 되는 것을 피할 수 있다. 또한 이 경우는 용량이 작은 부콘덴서(12)를 사용하므로, 역률이 크게 진행되는 것을 피할 수 있다. On the night of the weekday, both the effective power value P and the reactive power value Q become small. That is, T2 for the active power value P and the reactive power value Q

P <T1 and Q <T3 are established, the output of the comparator 74 is 0 while the output of the comparator 75 is 1, and the output of the comparator 76 is 0, thus outputting the logic circuit 77. The output of the logic circuit 78 becomes 1 while being 0. In this case, it is possible to avoid the delay power factor by controlling the sub-control unit 9 to open / close the sub-capacitor 12 having a small power capacity in accordance with the reactive power value Q. In this case, since the subcapacitor 12 having a small capacity is used, a large power factor can be avoided.

In addition, the effective power value P and the reactive power value Q are both further reduced during the holiday with the lowest power consumption, so that no capacitor is required. In this case, P <T2 is established with respect to the active power P, the output of the comparator 74 is zero, the output of the comparator 75 is zero, and the output of the comparator 76 is zero, thus the logic circuit ( While the output of 77 is zero, the output of logic circuit 78 becomes zero. In this case, as described above, both the main controller 8 and the sub-control unit 9 output the b signal and the a signal to the main switch 11 and the sub-opening unit 13, and all the main capacitors 10 and the sub-unit The condenser 12 is individualized. That is, since unnecessary waste of the condenser is not avoided, it is possible to avoid a large power factor.

As described above, according to the first embodiment, the delay power factor can be avoided regardless of the magnitude of the effective power value P and the magnitude of the reactive power value Q, and the power factor can be adjusted optimally.

In the above description, the power capacities of the main capacitor 10 and the subcapacitor 12 are all described as being the same, but this is not necessarily the same. In other words, the power capacities of the main capacitor 10 and the subcapacitor 12 may be different. In the above description, the capacity of one main capacitor 10 is larger than the total value of the capacities of the subcapacitors 12. However, this does not necessarily have to be large.

In the above description, the target power factor is described as 1, but the target power factor does not necessarily need to be 1, and if the value is close to 1, the power factor may be either the delayed power factor or the progressive power factor.

Embodiment 2.

In Embodiment 1, 3rd reference value T3 was demonstrated as what was determined based on the reactive power value Q previously measured using the electric power meter etc .. FIG. In contrast, in the second embodiment, the third reference value T3 is set based on the reactive power value Q at the time when the predetermined reference value setting signal is input without measuring the reactive power value in advance. Since the structure of the water substation system to which the power factor adjustment device 1 in Embodiment 2 is applied is the same as that in FIG. 1 in Embodiment 1, it is omitted. In Embodiment 2, the control part selection circuit 70 is applied instead of the control part selection circuit 7 of FIG.

FIG. 4 is a block diagram showing the control unit selection circuit 70 in the second embodiment, which corresponds to FIG. 3 in the first embodiment. 3, the same code | symbol is attached | subjected about the same part and description is abbreviate | omitted. In Fig. 4, the third reference value setting signal section 701, which is a reference value setting signal output means, outputs a logic signal 1 or 0. The maximum minimum reactive power storage control unit 702, which is the maximum minimum reactive power storage control means, stores based on the active power value P and the reactive power value Q transmitted from the power calculating unit 6, and the first reference value T1 and the second reference value T2. Determine the maximum reactive power Qmax and the minimum reactive power Qmin to be done. The maximum reactive power storage unit 703, which is the maximum reactive power storage unit, stores the maximum reactive power Qmax, and the minimum reactive power storage unit 704, which is the minimum reactive power storage unit, stores the minimum reactive power Qmin. The third reference value calculating section 705, which is a reference value calculating means, calculates based on the maximum reactive power Qmax and the minimum reactive power Qmin, and calculates the third reference value T3.

P < T1 이 성립되는 경우에 제3 기준치 T3이 설정된다. 이 경우, 비교기(74)의 출력은 논리 신호 0 으로 된다. 그러면 주제어부(8) 및 부제어부(9)에 의해, 주콘덴서(10) 및 부콘덴서(12)는 모두 개성 제어된다. 따라서, 제3 기준치 T3을 설정할 때에는 모든 콘덴서의 영향을 제외할 수 있다. The operation of the water substation system in the second embodiment will be described. Since normal operation is the same as that of the first embodiment, description thereof is omitted. In the second embodiment, the operation of setting the third reference value T3 is different from the first embodiment. The third reference value setting signal section 701 normally outputs a logic signal 0, but when setting the third reference value T3, it outputs a logic signal 1 as a reference value setting signal. When the logic signal 1 is outputted, the logic circuit 772 and the logic circuit 781 in the logic circuit 771 output the logic signal 0. At this time, when the effective power value P is less than the first reference value T1 and equal to or more than the second reference value T2, that is, T2

When P <T1 is established, the third reference value T3 is set. In this case, the output of the comparator 74 becomes a logic signal zero. Then, by the main control part 8 and the sub control part 9, both the main capacitor 10 and the sub capacitor 12 are individual-controlled. Therefore, the influence of all the capacitors can be excluded when setting the third reference value T3.

P < T1 인 경우에 동작한다. 그리고, 이미 최대 무효 전력 기억부(703)에 기억되어 있는 최대 무효 전력 Qmax 보다 무효 전력치 Q가 크면, 해당 무효 전력치 Q의 값을 새로운 최대 무효 전력 Qmax로서 최대 무효 전력 기억부(703)에 기억한다. 한편, 이미 최소 무효 전력 기억부(704)에 기억되어 있는 최소 무효 전력 Qmin 보다 무효 전력치 Q가 작으면, 해당 무효 전력치 Q의 값을 최소 무효 전력 Qmin 로서 최소 무효 전력 기억부(704)에 기억한다. 제3 기준치 연산부(705)는 최대 무효 전력 기억부(703)에 기억된 최대 무효 전력 Qmax와, 최소 무효 전력 기억부(704)에 기억된 최소 무효 전력 Qmin 과의 값의 중간치 Qave = (Qmax + Qmin) / 2를 산출하고, Qave를 제3 기준치 T3 로서 제3 기준치 설정부(73)에 전달한다. 제3 기준치 T3의 설정이 완료하면 기준치 설정 신호의 출력이 정지하고, 설정 동작이 완료한다. 즉 제3 기준치 설정 신호부(701)로부터 출력되는 논리 신호가 1 에서부터 0 으로 천이한다. When the maximum minimum reactive power storage control unit 702 sets the third reference value T3, that is, when the logic signal 1 is output from the third reference value setting signal unit 701, the effective power value P is T2.

It operates when P <T1. If the reactive power value Q is greater than the maximum reactive power Qmax already stored in the maximum reactive power storage 703, the value of the reactive power value Q is transferred to the maximum reactive power storage 703 as a new maximum reactive power Qmax. Remember On the other hand, if the reactive power value Q is smaller than the minimum reactive power Qmin already stored in the minimum reactive power storage 704, the value of the reactive power value Q is stored in the minimum reactive power storage 704 as the minimum reactive power Qmin. Remember The third reference value calculating section 705 determines the intermediate value Qave = (Qmax +) between the maximum reactive power Qmax stored in the maximum reactive power storage unit 703 and the minimum reactive power Qmin stored in the minimum reactive power storage unit 704. Qmin) / 2 is calculated, and Qave is transmitted to the third reference value setting unit 73 as the third reference value T3. When the setting of the third reference value T3 is completed, the output of the reference value setting signal is stopped, and the setting operation is completed. That is, the logic signal output from the third reference value setting signal unit 701 transitions from 1 to 0.

P 인 경우에는 최대 최소 무효 전력 기억 제어부(702)는 동작하지 않는다. 즉 최대 최소 무효 전력 기억제부(702)는 평일의 주간에 자가 발전 시스템(16)이 정지한 상태나 휴일과 같이, 제3 기준치 T3의 값에 관계 없이 제어를 행하는 경우에는 동작하지 않고, 제3 기준치 T3의 값이 제어에 관계하도록 된 조건하에서만 동작한다. By the above operation, the third reference value T3 can be set without measuring the reactive power value Q in advance. In addition, in the above-described operation, even when the logic signal 1 is output from the third reference value setting signal section 701, the effective power P is P <T2 or T1.

In the case of P, the maximum minimum reactive power storage control unit 702 does not operate. That is, the maximum minimum reactive power storage unit 702 does not operate when control is performed regardless of the value of the third reference value T3, such as a state in which the self-generating system 16 is stopped or a holiday on weekdays, and the third It operates only under the condition that the value of the reference value T3 is related to the control.

Embodiment 3.

In Embodiment 2, the case where the third reference value T3 is set without measuring the reactive power value Q in advance by using the reference value setting signal has been described. In Embodiment 3, the case where the 3rd reference value T3 is set based on the power capacity value of the main capacitor 10 and the sub capacitor 12 to be used is demonstrated. Since the structure of the water substation system to which the power factor adjustment apparatus 1 in Embodiment 3 is applied is the same as that of FIG. 1 in Embodiment 1, it abbreviate | omits. In Embodiment 3, the control part selection circuit 700 is applied instead of the control part selection circuit 7 of FIG.

FIG. 5 is a block diagram showing the control unit selection circuit 700 according to the third embodiment, and corresponds to FIG. 3 of the first embodiment and FIG. 4 of the second embodiment. In addition, the same code | symbol is attached | subjected about the same part as FIG. 3 or FIG. 4, and description is abbreviate | omitted. In Fig. 5, the main capacitor var value setting unit 7001, which is the first storage means, stores in advance the reactive power var value, which is the power capacity value of the main capacitor 10, and the sub capacitor var value setting unit (the second storage means) ( 7002 stores in advance the reactive power var value, which is the power capacity value of the subcapacitor 12. The third reference value calculating section 705, which is a reference value calculating means, calculates based on the main capacitor var value and the subcapacitor var value transmitted from the main capacitor var value setting unit 7001 and the subcapacitor var value setting unit 7002. The third reference value T3 is calculated.

In the third embodiment, the operation of the water substation system will be described. Since normal operation is the same as that of the first embodiment, description thereof is omitted. In the third embodiment, the main capacitor var value setting unit 7001 transfers the power capacity Q1 of one main capacitor 10 to the third reference value calculating unit 705. On the other hand, the subcapacitor var value setting unit 7002 transfers the sum Q2 of the power capacities of all the subcapacitors 12 to the third reference value calculating unit 705. The third reference value calculator 705 transmits (Q1 + Q2) / 2 to the third reference value setting unit 73 as the third reference value T3 based on Q1 and Q2.

By the above operation, according to Embodiment 3, 3rd reference value T3 can be set, similarly to Embodiment 2, without measuring reactive power value Q previously.

Embodiment 4.

In the first embodiment, the capacity of the capacitor is controlled by selectively opening and closing the main capacitor 10 or the subcapacitor 12 in accordance with the reactive power value Q, and as a result, it has been described as controlling so as not to become a delay power factor. In contrast, in Embodiment 4, the delay power factor is allowed, the control is performed so that the power factor is closest to 1, and the control is performed so as not to become an extreme progressive power factor. In Embodiment 4, the 1st main control part 81 and the 2nd main control part 82 are applied instead of the main control part 8 of FIG.

FIG. 6 is a block diagram showing the configuration of the water substation system according to the fourth embodiment, which corresponds to FIG. 1 of the first embodiment. In addition, about the same part as FIG. 1, the same code | symbol is attached | subjected and description is abbreviate | omitted. In FIG. 6, the control part selection circuit 17 of the power factor adjustment apparatus 1 outputs the 3rd determination value 7c and the 4th determination value 7d instead of the 1st determination value 7a. Among them, the third determination value 7c is transmitted to the first main control unit 81. In addition, the fourth determination value 7d is transmitted to the second main control unit 82.

In the fourth embodiment, the operation of the water substation system will be described. Since the operation until the power calculating section 6 outputs the effective power value P and the reactive power value Q is the same as in the first embodiment, description thereof is omitted. In Embodiment 4, the control part selection circuit 17 outputs the 3rd determination value 7c and the 4th determination value 7d instead of the 1st determination value 7a. FIG. 7 is a block diagram showing the control unit selection circuit 17 according to the fourth embodiment, and corresponds to FIG. 3 of the first embodiment, FIG. 4 of the second embodiment, or FIG. 5 of the third embodiment. In addition, the same code | symbol is attached | subjected about the same part as FIGS. 3-5, and description is abbreviate | omitted. In Fig. 7, the comparator 74 compares and determines the magnitude of the first reference value T1 and the effective power value P, and outputs the logic signal 1 as the third determination value 7c when the effective power value P is equal to or larger than the first reference value T1. When the effective power value P is less than the first reference value T1, the logic signal 0 is output as the third determination value 7c. When the output signal of the comparator 74 is 0, the output signal of the comparator 75 is 1, and the output signal of the comparator 76 is 1, the logic circuit 79 sets the logic signal 1 as the fourth determination value 7d. ), And the logic signal 0 is output as the fourth determination value 7d at other conditions.

P가 성립하는 경우, 제1 주제어부(81)가 실시 형태 1에 있어서의 주제어부(8)와 동일한 동작을 행하여 지연 역률로 되는 것을 회피한다. The first main controller 81 has a value of the reactive power value Q transmitted from the power calculating section 6 and the power capacity of the main capacitor 10 according to the third determination value 7c transmitted from the control section selection circuit 17. Based on this, the B signal for closing the main capacitor 10 and the b signal for modifying are output to the main opening / closing unit 11. That is, T1 as in the state where the self-generation system 16 is stopped in the weekday week.

When P holds, the first main control section 81 performs the same operation as that of the main control section 8 in the first embodiment to avoid a delay power factor.

On the other hand, the second main controller 82 controls the value of the reactive power value Q transmitted from the power calculating section 6 and the main capacitor 10 according to the fourth determination value 7d transmitted from the control section selection circuit 17. Based on the power capacity, the B signal for closing the main capacitor 10 and the b signal for modifying are output to the main switch 11 so that the power factor becomes a value closest to one.

P < T1 과 동시에 T3

Q 가 성립되고, 또한 지연 역률로 되는 것이 허용되는 경우에는 제2 주제어부(82)가 제1 주제어부(81)에 대신하여 동작한다. 즉 제2 주제어부(82)는 주개폐부(11)에 의해 주콘덴서(10)를 선택적으로 개폐 제어하고, 지연 역률을 허용하면서 역률이 1에 가장 가깝게 되는 제어를 행하여, 극단적인 진보 역률로 되지 않게 제어한다. 또한 상기의 경우, 부제어부(9)도 제2 주제어부(82)와 동일하게, 역률 1에 가장 가깝게 되는 제어를 행한다. 또 이후의 동작은 실시 형태 1에 있어서와 동일하기 때문에 설명을 생략한다. Specifically, T2 as in the state in which the self-generation system 16 is operated during the weekday.

T3 simultaneously with P <T1

When Q is established and the delay power factor is allowed, the second main controller 82 operates in place of the first main controller 81. That is, the second main controller 82 selectively controls the main capacitor 10 by the main opening / closing unit 11, and controls the power factor to be closest to 1 while allowing the delay power factor to become an extreme progressive power factor. Control it. In addition, in the above-described case, the sub-control unit 9 also performs control closest to the power factor 1 similarly to the second main control unit 82. Since the subsequent operations are the same as those in the first embodiment, description thereof is omitted.

As described above, according to the fourth embodiment, the power factor can be adjusted regardless of the magnitude of the effective power value P or the magnitude of the reactive power value Q, and it can be controlled so as not to become an extreme progressive power factor.

According to the present invention, when the effective power value is greater than or equal to the first reference value, or when the effective power value is less than or equal to the second reference value and the reactive power value is greater than or equal to the third threshold, the large-capacity capacitor opens and closes according to the reactive power value. On the other hand, when the effective power value is less than the first reference value, is greater than or equal to the second reference value, and the reactive power value is less than the third threshold value, the small-capacity capacitor is controlled to open and close according to the reactive power value. Even if it becomes large, it has the effect of being able to adjust to the optimal power factor irrespective of the magnitude | size of an effective electric power value and an reactive power value.

Claims (7)

Power calculating means for calculating an effective power value and a reactive power value based on a voltage value and a current value in a power system; Outputting a first control signal when the effective power value is greater than or equal to a predetermined first reference value, or when the effective power value is less than or equal to the first reference value and greater than or equal to a predetermined second reference value, and the reactive power value is greater than or equal to a predetermined third reference value; Control signal generating means for outputting a second control signal when the effective power value is less than the first reference value, is greater than or equal to the second reference value, and the reactive power value is less than the third reference value; Selectively closing two or more first capacitors connected to the power system via a first opening / closing means based on the first control signal and the reactive power value to close and close the first opening / closing means. First control means for outputting a first open / close signal for selectively controlling the first condenser, which is not present, by individually controlling the first open / close means; Selectively controlling the second opening and closing means for at least one second capacitor connected to the power system via a second opening and closing means based on the second control signal and the reactive power value and having a smaller capacity than the first capacitor; And second control means for outputting a second open / close signal for selectively controlling the second open / close means by closing the second condenser that is closed and not closed. The method of claim 1, And the third reference value is an intermediate value between the maximum value and the minimum value of the reactive power value when the effective power value is less than the first reference value and is greater than or equal to the second reference value. The method of claim 1, Reference value setting signal output means for outputting a reference value setting signal for setting said third reference value while personalizing said first opening and closing means and said second opening and closing means; A maximum minimum reactive power storage control means for determining a maximum value and a minimum value of the reactive power value based on the reference value setting signal; Maximum reactive power storage means for storing a maximum value of the reactive power value; Minimum reactive power storage means for storing the minimum value of the reactive power value; And a reference value calculating means for calculating an intermediate value between the maximum value of the reactive power value stored in said maximum reactive power storage means and the minimum value of the reactive power value stored in said minimum reactive power storage means, and setting it as said third reference value. Adjustment device. The method of claim 1, First storage means for storing a capacity of said first capacitor; Second storage means for storing a capacity of the second capacitor; A reference value calculating means for calculating an intermediate value of the sum of the minimum capacity of the first capacitors stored in the first storage means and the capacity of the second capacitor stored in the second storage means, and setting the reference value to the third reference value; The power factor adjustment device characterized by the above-mentioned. The method according to any one of claims 1 to 4, And the first control means outputs a first open / close signal in which the power factor becomes equal to or greater than a predetermined value. The method according to any one of claims 1 to 4, And the first control means outputs a first open / close signal in which the power factor is closest to a predetermined value. Power calculating means for calculating an effective power value and a reactive power value based on a voltage value and a current value in a power system; Outputting a first control signal when the effective power value is greater than or equal to a predetermined first reference value, and when the effective power value is less than the first reference value and greater than or equal to a predetermined second reference value, and the reactive power value is greater than or equal to a predetermined third reference value; Control signal generating means for outputting a second control signal and outputting a third control signal when the effective power value is less than the first reference value and is greater than or equal to the second reference value and the reactive power value is less than the third reference value; Selectively controlling two or more first capacitors connected to the power system via first opening and closing means based on the first control signal and the reactive power value such that the power factor is equal to or greater than a predetermined value; First control means for outputting a first open / close signal for selectively closing the closed and non-closed first capacitors; Selectively closing the first condenser based on the second control signal and the reactive power value and controlling the first opening / closing means such that the power factor is closest to a predetermined value, and closing the first condenser which is not closed; Second control means for selectively controlling the first opening and closing means to output a second opening and closing signal for individualizing; Selectively controlling the second opening and closing means for at least one second capacitor connected to the power system via a second opening and closing means based on the third control signal and the reactive power value and having a smaller capacity than the first capacitor; And a third control means for outputting a third open / close signal for selectively controlling the second open / close means for closing the second condenser that is closed and not closed.

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