CN-116247732-B - Method, device and medium for controlling receiving-end tapping switch of SLCC phase-change technology

CN116247732BCN 116247732 BCN116247732 BCN 116247732BCN-116247732-B

Abstract

The invention relates to a receiving-end tapping switch control method of an SLCC phase change technology, which comprises the steps of establishing an equivalent model of corresponding actions of the receiving-end tapping switch according to a topological structure of the SLCC, and calculating the action times of the receiving-end tapping switch according to a set control strategy of the receiving-end tapping switch. The equivalent model comprises a converter transformer branch connected with a high-voltage direct-current power transmission end and an SVG branch, wherein the converter transformer branch Is connected with the SVG branch at a grid-connected point, the converter transformer branch comprises an alternating-current power supply Us and impedance which are connected, the reactive power of a system in the converter transformer branch Is exchanged into Qs, the reactive power consumption of the converter transformer Is Qtr, the voltage of a converter transformer valve side Is Uv, the current of the converter transformer valve side Is, the equivalent model also comprises a passive filter branch, the passive filter branch Is connected with the alternating-current power supply Us in parallel, the capacity of the passive filter branch Is Qacf, the capacity of the SVG branch Is Qsvg, and the branch current Is Isvg. According to the scheme, the aim of reducing the action times of the receiving-end tapping switch is fulfilled.

Inventors

MA WEIMIN
JI YIMING
DU SHANGAN
YIN JIAN
GUO ZIYU
HUANG CAOWEI
WANG YAOXUAN
WANG AO
HUANG YONG
WANG LING
LI MING
WU FANGJIE
SHEN XIAOLIN
ZHU QUANLE
XU YING
ZHANG TAO

Assignees

国网经济技术研究院有限公司

Dates

Publication Date: 20260508
Application Date: 20230322

Claims (4)

1. The method for controlling the receiving end tapping switch of the SLCC phase change technology is characterized by comprising the following steps of: Establishing an equivalent model of the corresponding action of the receiving-end tapping switch according to the topological structure of the SLCC; Calculating the action times of the receiving-end tapping switch according to a set receiving-end tapping switch control strategy; The equivalent model comprises a converter transformer branch and an SVG branch, wherein the converter transformer branch is connected with a high-voltage direct-current transmission end, and the converter transformer branch is connected with the SVG branch at a grid-connected point; the converter transformer branch comprises an alternating current power supply Us and impedance which are connected, wherein the reactive power of the system in the converter transformer branch Is Qs, the reactive power consumption of the converter transformer Is Qtr, the voltage of the converter transformer valve side Is Uv, and the current of the converter transformer valve side Is; The equivalent model further comprises a passive filter branch, wherein the passive filter branch is connected with the alternating current power Us in parallel, and the capacity of the passive filter branch is Qacf; the capacity of the SVG branch is Qsvg, and the branch current is Isvg; The control strategy of the receiving-end tapping switch specifically comprises dynamic movement of the reactive power exchange junction zero point; The calculating the action times of the receiving-end tapping switch according to the set control strategy of the receiving-end tapping switch comprises the following steps: Setting a direct current power operation interval of a high-voltage direct current transmission end; setting constraint conditions of passive filter configuration and reactive exchange; determining a reactive power exchange junction zero operation power point; and iteratively calculating the tap switch action times of the receiving-end tap switch at the reactive power exchange junction zero-running power point.
2. A receiver tap changer control device for SLCC phase inversion technology, the device comprising: The model building module is used for building an equivalent model of the corresponding action of the receiving end tapping switch according to the topological structure of the SLCC; the action calculation module is used for calculating the action times of the receiving-end tapping switch according to a set control strategy of the receiving-end tapping switch; The equivalent model comprises a converter transformer branch and an SVG branch, wherein the converter transformer branch is connected with a high-voltage direct-current transmission end, and the converter transformer branch is connected with the SVG branch at a grid-connected point; the converter transformer branch comprises an alternating current power supply Us and impedance which are connected, wherein the reactive power of the system in the converter transformer branch Is Qs, the reactive power consumption of the converter transformer Is Qtr, the voltage of the converter transformer valve side Is Uv, and the current of the converter transformer valve side Is; The equivalent model further comprises a passive filter branch, wherein the passive filter branch is connected with the alternating current power Us in parallel, and the capacity of the passive filter branch is Qacf; the capacity of the SVG branch is Qsvg, and the branch current is Isvg; The control strategy of the receiving-end tapping switch specifically comprises dynamic movement of the reactive power exchange junction zero point; the action calculation module is used for setting a direct current power operation interval of a high-voltage direct current transmission end, setting constraint conditions of passive filter configuration and reactive power exchange, determining a reactive power exchange junction zero operation power point, and iteratively calculating the tap switch action times of a receiving end tap switch at the reactive power exchange junction zero operation power point.
3. A computer readable storage medium, wherein a computer program is stored in the computer readable storage medium, and when the computer program runs, the computer program controls a device where the computer readable storage medium is located to execute the method for controlling the end tap changer of the SLCC phase inversion technology of claim 1.
4. A computer device comprising a memory and a processor, the processor storing a computer program, the processor executing the computer program to implement the method of controlling an on-hook tap changer of the SLCC commutation technique of claim 1.

Description

Method, device and medium for controlling receiving-end tapping switch of SLCC phase-change technology Technical Field The invention relates to the technical field of direct current transmission, in particular to a method and a device for controlling a receiving end tapping switch of SLCC (Statcom and line commutation converter) commutation technology and a computer readable storage medium. Background Direct current transmission is a backbone transportation channel of energy sources and plays an irreplaceable role in energy source transportation. Aiming at the problems of large-scale clean energy grid connection, transmission, digestion and the like, direct current transmission is a necessary means for further improving the utilization rate of clean energy, fully meeting the future power demand and assisting the construction of a novel power system. The traditional design concept considers that with the development of a power system, the system strength is continuously improved, and the direct current transmission has better performance and stability. However, with the access of large-scale new energy, a number of problems have been exposed. For example, voltage fluctuation caused by filter switching is increased, switching is frequently performed, overvoltage of a power grid at a power transmission end has an increasing trend when a direct current transmission system is disturbed, fan operation is threatened, and along with the increase of engineering scale, the occupied area of a converter station is large, and the like. For the problems exposed by the conventional design, technologies such as LCC, VSC, and SLCC are correspondingly proposed. The SLCC converter technology is a converter technology with characteristics of a composite voltage source and a current source, and can realize the performance optimization and upgrading of LCC combined with VSC. The SLCC commutation technology has the advantages of (1) reducing the dependence of direct-current transmission on an alternating-current system, improving dynamic reactive power characteristics, flexibly adapting to new energy island feed-in, reducing commutation failure risks and equipment safety risks, (2) realizing harmonic and reactive power self-compensation, canceling a large number of filter configurations, greatly reducing the occupied area of a converter station and improving environmental adaptability, (3) effectively inhibiting oscillation risks caused by voltage source characteristics of the VSC direct-current transmission technology, and (4) solving the problem of capacity scale limitation of the VSC direct-current transmission technology. The technology greatly improves the flexibility and adaptability of the direct current transmission technology in the direct current transmission scene of new energy grid connection under the situation of the development of a novel power system in the future. However, the inventor of the present application found in the study that, as a new technology, the topology structure of the SLCC reduces the number of actions of the send-side tap changer on the one hand, and increases the number of actions of the receive-side tap changer on the other hand, and the increase of the receive-side tap changer increases the risk of a converter fault, which jeopardizes the safe operation of the converter station. Disclosure of Invention Aiming at the problems, the invention aims to provide a receiving end tapping switch control method, a device and a medium for an SLCC phase-change technology, which can flexibly adjust a tapping switch control strategy according to working conditions, achieve the aim of reducing the action times of the tapping switch and widen the adaptability of the SLCC phase-change technology. In order to achieve the above purpose, the present invention adopts the following technical scheme: The application provides a receiving end tapping switch control method of an SLCC phase change technology, which comprises the following steps: Establishing an equivalent model of the corresponding action of the receiving-end tapping switch according to the topological structure of the SLCC; and calculating the action times of the receiving-end tapping switch according to the set control strategy of the receiving-end tapping switch. In one implementation mode of the application, the equivalent model comprises a converter transformer branch connected with a high-voltage direct-current transmission end and an SVG branch, wherein the converter transformer branch is connected with the SVG branch at a grid-connected point; the converter transformer branch comprises an alternating current power supply Us and impedance which are connected, wherein the reactive power of the system in the converter transformer branch Is Qs, the reactive power consumption of the converter transformer Is Qtr, the voltage of the converter transformer valve side Is Uv, and the current of the converter transformer valve side Is; the equivalent mode