JPH02144616A - Cooperative operation control system for reactive power compensating device - Google Patents

Abstract

PURPOSE:To attain the cooperative operation control with a quip response by comparing the outputs of control circuits with each other in a reactive power compensating device (SVC) so that the same quantity of reactive power is generated, integrating a difference by an integrator, adding the output of the integrator to the input of an arithmetic circuit to be followed in the SVC to always compensate reactive power. CONSTITUTION:A difference signal to be the output of an adder 88 for comparing a reactive power supply signals from limiter circuits 85, 95 with each other is added to the input of the limiter circuit 85 by an adder 82 through an integrating circuit 89. In this case, an SVC 1 is controlled so as to follow up an SVC 2, and in the case of allowing the SVC 2 to follow up the SVC 1, an output signal from the circuit 89 may be added to an adder 92. Thus, cooperative operation between the SVC 1 and SVC 2 can be quickly attained by setting up the time constant of the integrating circuit 89 to approximately the same as the integration constants of proportional integrators 84, 94.

Description

[Detailed Description of the Invention] [Industrial Applicability] The present invention provides a voltage fluctuation control function for a grid, and a variable power compensator (hereinafter abbreviated as SVC) connected to another same grid. j! in cooperative operation of multiple SvCs! This is related to the 4-way method.

[Background technology and problems] SVC installed in a substation performs constant voltage control (referred to as VR control) on the system voltage and suppresses voltage fluctuations, but when an SVC to be added to the system and an existing SVC are linked, for example, If there is a slight difference in the reference voltage and each detection input such as voltage, current, etc., the system will operate in the completely opposite manner, resulting in problems such as magnifying voltage fluctuations and disrupting the system. The following are specific measures to prevent these problems.

(1) Improve the performance of voltage and current detection circuits and reference voltage circuit components, and readjust each control constant to a constant that suits the site.

(2) Figure 2 (a) shows syc i and 5VC2 connected to the grid, and % (+1) indicates its control circuit.

Here, the voltage vl of the bus to which sve t is connected is assumed to be the voltage to be compensated for. PT, the voltage signal v, ,CT,
syc i current signal '6'IQ+ is detected, (
0) As shown in the figure, reactive power is detected by reactive power detector 0-01. Keita, voltage signal v,,,C from 1・T2
An energizing current signal 1°2 of 5vC2 is detected from T, .
Reactive power is detected by reactive power detector QTO2. The output signals from these QTOI and QTO2 are combined with the iR control signal, that is, the control signal from the VTO, and the voltage reference V
,. .

, and Vvar2 are captured and become control signals Q1 and Q2 of 5vci and SVC2, and cooperative operation is performed based on these Qx and Qs.

However, there is a limit to the response speed of the reactive power transducer (commercially available products O, SS), and when correcting the voltage standard using this signal, it generally takes about an order of magnitude longer than the response speed of the transducer. It is necessary to control with a delay (P, ! control) (several S), and high-speed response cooperative operation control cannot be expected.

[Objective and Structure of the Invention] As mentioned above, the object of the present invention is to prevent the conventional control method from causing system fluctuation in the case of cooperative operation of SVC, and to prevent this from occurring. This system enables cooperative operation control between S70 by comparing the control output signals and correcting the input of each SvC calculation circuit so that the difference becomes zero.

Note that one of the features of the present invention is that there is no need to detect the amount of reactive power of each SVC as in the conventional method shown in FIG.

In other words, it can be controlled by internal signals of the control device.

The present invention will be explained below with reference to embodiments shown in the drawings.

It is assumed that the system bus 3 is connected to the power supply 1.

Note that it is assumed that there is a power supply impedance 2 between them.

A transformer 5 is connected between the system bus 3 and the voltage compensation target bus G, and the tertiary winding of the transformer 5 is connected to a 5VC2 formed by connecting a reactor 9 and an anti-parallel connected thyristor in series. . In addition, the system bus 113 and the voltage compensation target bus θ
A transformer 4 is connected between the two. An SVC1 consisting of a reactor indicated by 8 and an anti-parallel connected thyristor connected in series is connected to the voltage compensation target bus 6, and voltage detection P7.7
are combined.

80 and 90 are kVR control devices each receiving a voltage signal from PTt 7 as input.

8■ is a detection circuit for vl, the voltage signal detected here is inputted to the proportional integrator 84 after subtracting the reference voltage signal v1aft of the bus 6 indicated by 100, and the output signal is inputted to the limiter circuit 85. do.

On the other hand, 91 is a detection circuit for v2, the voltage signal detected here is inputted to a proportional integrator 94 after subtracting the reference signal vrs, 2, and its output signal is inputted to a limiter circuit 95. Here, Vreri and Vrer2 are each V
, , is the reference voltage at V2.

Rimi! The evening circuit 85 corresponds to the control amount of 5VC1, and here, based on the correction voltage signal of the voltage of the voltage compensation target bus 6 output from the proportional integrator 84, the control amount of 5V is determined.
The reactive power amount i [f!
The signal VQI is kept within a control range of 5VCI by a limiter 85 and is inputted to a pulse generation circuit 87 via a 712217 circuit 86 to generate an ignition pulse.

On the other hand, the limiter circuit 95 corresponds to the control amount of 5VC2, and here, based on the correction voltage signal of the proportional integrator 94, a reactive power energization amount signal van is used to control the energization of 5ve2 and si-risk. is kept within the control range of 5VC2 and is input to the pulse generation circuit 97 via the 1-comb circuit 9G. - Generally, the voltage v3 to which 5VC2 is connected is different from the voltage V of the voltage compensation target bus, so the pulse generation circuit 97, unlike the pulse generation circuit 87, The firing pulse phase of is determined.

88 is an adder that compares the reactive power energization amount signals from the limiter circuits 85 and 95, and the difference between the outputs (No. 3 is added to the input of the limiter circuit 85 by the adder 82 via the integrating circuit 89. In the case of the example, 5VC1 is controlled to follow 5VC2, and if it is desired to make SVC2 follow 5YCI, the output signal from the integrating circuit 89 may be added to the adder 92.

Here, the time constant of the integrating circuit 89 is the proportional integrator 84°94
If the integral constant is made to be approximately the same as that of , cooperative operation of 5VCI and SvC2 can be realized at high speed. Further, the integral may be an incomplete integral.

IJ Mitter circuit 85. Control output of 81E, that is, reactive power amount N1 signal vQl = VQ2 based on SVC1,
The phase of the thyristor S%lC2 is controlled, the reactor current is increased or decreased, and the generated reactive power is adjusted for the voltage compensation target bus 6 to suppress voltage fluctuations.

The adder 88 compares the output signal "Ql" of the IJ l vine circuit 85 and the output signal "VQ2" of the 95, and Y, l>Y.

2, or if “Ql<’/Q2, this difference is calculated by the integrator 8.
9 and its output signal is added to the input of a limiter circuit 85 by an adder 82. With this signal, the minor loop is controlled so that Va becomes +''12.

If v, , &-FvQ2, then Q+=QB exists.”I
! , 5VC1 and 5vC2 have the same amount of generated reactive power, and cooperative operation control is performed.

[Effect of the invention] In the present invention, the outputs of the control circuits of these SVCs are compared and the difference is integrated by an integrator so that the same amount of reactive power is generated in the SVCs operated in coordination. Since this output is added to the input of the arithmetic circuit of the SYC to be tracked and constantly corrected, there is no need to use high-precision parts for the control circuit of each SVC or to make delicate on-site adjustments as in the past. , it is possible to smoothly perform cooperative operation control of syci and SVC2.

Furthermore, since the present invention does not require a transformer or the like for detecting the amount of reactive power, it is advantageous in terms of equipment costs and reliability.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of the invention. Figure 2 (a) shows the arrangement of multiple SVCs in the system,
(0) indicates a control circuit for interlocking operation of the SvC. 7... Voltage detection P-d, 8 ・5VC2, 9-5VC1
゜80.90...mu VR control device, 81.91-...
Voltage detection circuit, 82.92... Adder, 83.93.
・・Reference voltage signal, 84.94 ・・Proportional integrator, 85
．． 95...Limiter circuit, 88.98...Funk scene circuit, 87.97...Pulse generation circuit, 8t.
・Integrator circuit, 100...Reference value signal. Shima 1 figure 2 shaku (ro)

Claims (1)

[Claims] (1) In the interlocking operation of the reactive power compensator installed for the purpose of controlling voltage fluctuations in the grid, the difference signal between the voltage signal of the voltage compensation target bus and the reference voltage signal of each bus is transmitted through each proportional-integral circuit. It is input to an arithmetic circuit and calculates the thyristor control reactive power energization amount signal of each reactive power compensator, and the difference between the reactive power energization amount signals is integrated in an integrating circuit, and the reactive power to be made to follow the integral output is A cooperative operation control method for a reactive power compensator, characterized in that a plurality of reactive power compensators are controlled in a cooperative manner by adding to an input of an arithmetic circuit of the power compensator.