System for realizing hybrid reactive compensation control by matching SVG with FC

Abstract

The utility model relates to a control system for realizing hybrid reactive compensation by matching SVG with FC, a plurality of static var generators SVG, a plurality of reactive compensation devices FC and a plurality of main transformers are provided, the input end of each main transformer is connected with a high-voltage bus, the output end of each main transformer is respectively connected with the corresponding static var generator SVG and the corresponding reactive compensation device FC, and the output end of each main transformer is connected with the high-voltage bus. The main controller is connected with the static var generators (SVG) through a communication port and is used for mutual parameter transmission between the static var generators (SVG), and the static var generators (SVG) are connected with the reactive compensation device (FC). The utility model has the advantages that the plurality of static var generators (SVGs) and the plurality of reactive compensation devices (FCs) operate in parallel, so that in the operation process, if a certain static var generator (SVG) or a certain reactive compensation device (FC) fails, the failed static var generator (SVG) or the failed reactive compensation device (FC) is cut off, the operation of other equipment is not influenced, and the service life of the equipment is prolonged. And the reliability, safety and maintenance convenience of a power grid system are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of reactive power compensation devices, in particular to a hybrid reactive power compensation control system realized by combining SVG with FC. Background Art

[0002] The static var generator SVG is the representative of the latest technology in the field of reactive power compensation today. It has superior performance in aspects such as response speed, stabilizing grid voltage, reducing system losses, increasing transmission capacity, raising transient voltage limit, reducing harmonics, and decreasing floor area. The SVG is connected in parallel to the power grid, equivalent to a variable reactive current source, and its reactive current can quickly follow the change of the load reactive current to compensate the reactive power required by the system. With the increasing number of new energy power generation devices connected to the grid, the demand for reactive power is constantly changing. Using the static var generator SVG alone will result in problems of reactive power and harmonic compensation capacity limitations. The combination of SVG and FC for hybrid reactive power compensation has become a development trend. However, in some power networks, a single set of SVG combined with FC hybrid reactive power compensation system is adopted. If the SVG or FC fails during operation, it will affect the safety of the power grid. Summary of the Invention

[0003] The purpose of the utility model is to provide a hybrid reactive power compensation control system realized by combining SVG with FC. The output ends of multiple transformers are connected in parallel with multiple static var generators SVG and reactive power compensation devices FC. Multiple static var generators SVG can achieve parameter inter - transmission between the static var generators SVG through the main controller. During operation, removing the faulty static var generator SVG or reactive power compensation device FC will not affect the operation of the remaining devices, increasing the reliability and safety of the power grid system, facilitating maintenance, having a simple structure, and being easy to implement.

[0004] To achieve the above purpose, the utility model is realized through the following technical solutions:

[0005] A hybrid reactive power compensation control system realized by combining SVG with FC includes a static var generator SVG, a reactive power compensation device FC, a main controller, and a main transformer. The number of the static var generator SVG, the reactive power compensation device FC, and the main transformer is multiple. The input end of each main transformer is connected to the high - voltage bus, and the output end of each main transformer is respectively connected to the corresponding static var generator SVG and reactive power compensation device FC. The main controller is connected to the static var generator SVG through a communication port for parameter inter - transmission between the static var generators SVG, and the static var generator SVG is connected to the reactive power compensation device FC.

[0006] The static var generator SVG includes a control cabinet and a power cabinet. The control cabinet is connected to the power cabinet through a communication port, and the power cabinet is used to receive the instructions of the control cabinet to make the power unit IGBT act;

[0007] The control cabinet includes a single-board controller. The power units of the power cabinet are connected to the single-board controller, and the single-board controller integrates the functions of a CPU board, an analog board, a digital board, and a PWM board.

[0008] The single-board controller generates a PWM modulation signal and sends it to the power units of the power cabinet through optical fibers, and drives the reactive power compensation device FC to switch on and off.

[0009] The main control chip of the single-board controller includes a DSP and an FPGA. The chip of the DSP is ADI-21489, and the chip of the FPGA is Altera-5CEFA7.

[0010] The reactive power compensation device FC includes a circuit breaker, a reactor, and a capacitor connected in series. The single-board controller also includes a digital board, and the normally open auxiliary contact of the circuit breaker is connected to the output end of the digital board.

[0011] The power cabinet includes several power units in three phases. The power units are connected in series through communication port optical fibers, and the power units adopt an H-bridge series topology structure.

[0012] The control cabinet also includes a voltage detection board PT and a current detection board CT. The voltage detection board PT is used to collect the input and output voltage signals of the corresponding transformer, and the current detection board CT is used to collect the input and output current signals of the corresponding transformer, and both are connected to the single-board controller through analog input ports.

[0013] The output end of each main transformer is also connected to the corresponding RL load.

[0014] Compared with the prior art, the beneficial effects of the present utility model are:

[0015] 1. By operating multiple sets of static var generators SVG in parallel with multiple sets of reactive power compensation devices FC, during the operation process, if a certain set of static var generator SVG or a certain set of reactive power compensation device FC fails, the faulty static var generator SVG or reactive power compensation device FC is cut off, which will not affect the operation of the remaining equipment, increasing the reliability, safety, and convenience of maintenance of the power grid system;

[0016] 2. By connecting the main controller to multiple sets of static var generators SVG, when a single set of SVG power system fails, the parameter intertransmission between other static var generators SVG is still realized, and the switching of the reactive power compensation device FC is completed to ensure the reliability of reactive power compensation;

[0017] 3. By operating multiple sets of static var generators SVG in parallel with multiple sets of reactive power compensation devices FC, through the fast compensation characteristics of SVG and the switching of FC, the fast response of the compensation system is improved;

[0018] 4. The operator performs manual switching operations through the switching buttons set on the upper computer. Moreover, the operator can view the operating status of the equipment at any time through the upper computer, which is convenient for maintenance and operation. Description of the Drawings

[0019] Figure 1 It is a topology structure block diagram of the hybrid reactive power compensation control system implemented by SVG in cooperation with FC.

[0020] Figure 2 It is an SVG reactive power distribution block diagram of the hybrid reactive power compensation control system implemented by SVG in cooperation with FC.

[0021] Figure 3 It is a schematic diagram of the parallel principle of SVG and FC in the hybrid reactive power compensation control system implemented by SVG in cooperation with FC. Detailed Implementation Modes

[0022] The present utility model will be described in detail below with reference to the drawings in the specification. However, it should be noted that the implementation of the present utility model is not limited to the following embodiments.

[0023] The following embodiments are implemented on the premise of the technical solution of the present utility model, and detailed implementation modes and specific operation processes are given. However, the protection scope of the present utility model is not limited to the following embodiments. The methods used in the following embodiments are all conventional methods unless otherwise specified.

[0024]

Embodiment 1

[0025] See Figure 1 , Figure 2 , a hybrid reactive power compensation control system implemented by SVG in cooperation with FC, including a static var generator SVG, a reactive power compensation device FC, a main controller, and a main transformer. The main controller adopts a single-board controller. The number of main transformers is three, namely main transformer 1, main transformer 2, and main transformer 3. The number of static var generators SVG is three, namely SVG1, SVG2, and SVG3. The number of reactive power compensation devices FC is six. The input ends of main transformer 1, main transformer 2, and main transformer 3 are all connected to the high-voltage bus 220KV. The output ends 35KV of main transformer 1, main transformer 2, and main transformer 3 are respectively connected to SVG1, SVG2, and SVG3. The output ends of main transformer 1, main transformer 2, and main transformer 3 are also respectively connected to two reactive power compensation devices FC. The output ends of main transformer 1, main transformer 2, and main transformer 3 are also respectively connected to the corresponding RL loads. See Figure 3, the master controller, as the host for the parallel operation of multiple sets of SVG, is connected to the communication ports of the single-board controllers in the slave units SVG1, SVG2, and SVG3 through multimode ST optical fibers, enabling the mutual transmission of parameters among SVG1, SVG2, and SVG3. The slave units SVG1, SVG2, and SVG3 send the collected grid current, SVG current, along with the FC status, FC enable signal, and FC permit closing signal to the master controller through ST communication optical fibers. The master controller performs the reactive power distribution of each slave SVG and the switching of the FC.

[0026] The master controller of the control cabinet is a single-board controller, which integrates the functions of a CPU board, an analog board, a digital board, and a PWM board; the single-board controller generates PWM modulation signals and sends them to the power units of the power cabinet through optical fibers, collects the FC status through the digital input board, and controls the switching of the reactive power compensation device FC through the digital output board. The main control chips of the single-board controller include a DSP and an FPGA. The chip of the DSP is ADI-21489, and the chip of the FPGA is Altera-5CEFA7. The reactive power compensation device FC includes a circuit breaker, a reactor, and a capacitor connected in series. The normally open auxiliary contact of the circuit breaker is connected to the output terminal of the digital board and is connected to the single-board controller through a DB37 communication line. The control cabinet also includes a PT voltage detection board and a CT current detection board. The PT voltage detection board is used to collect the input and output voltage signals of the corresponding transformer, and the CT current detection board is used to collect the input and output current signals of the corresponding transformer, both of which are connected to the single-board controller through analog input ports.

[0027] The input terminal of the digital board in the control cabinet also collects the closing and opening status of the FC circuit breaker, the FC fault status, and the FC control knob status. The single-board controller sends the status of each FC, the FC enable signal, and the FC permit closing signal to the master controller; the cooperative reactive power compensation device FC is used to switch the fixed capacitive capacity to cooperate with the SVG to achieve reactive power compensation when the SVG compensation capacity is insufficient or the SVG fails to complete full reactive power compensation. The input of the FC can be switched by the input knob set on the upper computer. The power cabinet includes several power units in three phases, and the power units are connected in series through communication port optical fibers, and the power units adopt an H-bridge series topology structure.

[0028] Working process:

[0029] The main controller summarizes the reactive power commands that each SVG needs to compensate, and performs reactive power distribution and FC switching control for each SVG. When the system control target is reactive power, the inductive reactive power threshold and capacitive reactive power threshold are used as the judgment conditions for inputting and removing FC. When the system control target is voltage, the lower voltage threshold and upper voltage threshold are used as the judgment conditions for inputting and removing FC. The main controller distributes the FC switching commands to each SVG, and the SVG directly controls the FC switching under the same section of bus. There is a bus coupler installed on the 35kV side of the three main transformers. After the bus coupler is closed, all the SVG and FC under the 35kV of the three main transformers are in parallel operation. When there is a fault in the SVG power system, since the control system and the optical fiber hardware transmission are normal, the main controller can still calculate the compensated reactive power and FC switching commands and distribute them to the SVG control system with a power module fault.

[0030] The utility model operates in parallel with multiple sets of static var generators SVG and multiple sets of reactive power compensation devices FC. During operation, if a fault occurs in a certain set of static var generators SVG or a certain set of reactive power compensation devices FC, removing the faulty static var generators SVG or reactive power compensation devices FC will not affect the operation of the remaining equipment, increasing the reliability, safety, and convenience of maintenance of the power grid system; the main controller is connected to multiple sets of static var generators SVG. When a single set of SVG power system fails, the parameters can still be transmitted between other static var generators SVG, and the switching of the reactive power compensation device FC is completed to ensure the reliability of reactive power compensation; by operating multiple sets of static var generators SVG and multiple sets of reactive power compensation devices FC in parallel, the fast response of the compensation system is improved through the fast compensation characteristics of SVG and the switching of FC; the operator can perform manual switching operations through the switching buttons set on the upper computer, and the operator can view the operation status of the equipment at any time through the upper computer, which is convenient for maintenance and operation.

Claims

1. A hybrid reactive power compensation control system implemented by SVG and FC, characterized in that: The invention comprises a static VAR generator SVG, a reactive power compensation device FC, a main controller and a main transformer. There are multiple static VAR generators SVG, reactive power compensation devices FC and main transformers. The input end of each main transformer is connected to the high-voltage bus. The output end of each main transformer is respectively connected to the corresponding static VAR generator SVG and reactive power compensation device FC. The main controller is connected to the static VAR generator SVG through a communication port for mutual transmission of parameters between the static VAR generators SVG. The static VAR generator SVG and reactive power compensation device FC are connected through a port.

2. According to claim 1, a hybrid reactive power compensation control system using SVG in conjunction with FC is characterized in that: The static VAR generator SVG comprises a control cabinet and a power cabinet. The control cabinet is connected to the power cabinet via a communication port. The power cabinet is used to receive instructions from the control cabinet to activate the power unit IGBT. The control cabinet includes a single-board controller, and the power unit of the power cabinet is connected to the single-board controller. The single-board controller integrates the functions of the CPU board, analog quantity board, digital quantity board, and PWM board; The single-board controller generates a PWM modulation signal and sends it to the power unit of the power cabinet through an optical fiber, and drives the reactive power compensation device FC to switch on and off.

3. The hybrid reactive power compensation control system implemented by SVG and FC according to claim 2 is characterized in that: The main control chip of the single-board controller includes DSP and FPGA, the DSP chip is ADI-21489, and the FPGA chip is Altera-5CEFA7.

4. The hybrid reactive power compensation control system implemented by SVG and FC according to claim 2 is characterized in that: The reactive power compensation device FC comprises a circuit breaker, a reactor and a capacitor connected in series, and the single-board controller further comprises a digital quantity board, and the normally open auxiliary contact of the circuit breaker is connected to the output end of the digital quantity board.

5. The hybrid reactive power compensation control system implemented by SVG and FC according to claim 2 is characterized in that: The power cabinet comprises a plurality of three-phase power units, the power units are connected in series via optical fibers of communication ports, and an H-bridge series topology structure is adopted between the power units.

6. The hybrid reactive power compensation control system implemented by SVG and FC according to claim 2 is characterized in that: The control cabinet also includes a voltage detection board PT and a current detection board CT. The voltage detection board PT is used to collect voltage signals at the input and output ends of the corresponding transformer, and the current detection board CT is used to collect current signals at the input and output ends of the corresponding transformer, both of which are connected to the single-board controller through the analog input port.

7. The hybrid reactive power compensation control system implemented by SVG and FC according to claim 1 is characterized in that: The output terminal of each main transformer is also connected to a corresponding RL load.

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