Research on Short-time Current Test Method of DC Circuit Breaker Used in DC Grid

Abstract

DC power grid technology puts forward new requirements for equipment. High-voltage DC circuit breakers with fast breaking capability are the core equipment of DC power grids. The existing test technology can not meet the short-term current tolerance requirements of DC circuit breakers in terms of power. In order to solve this problem, this paper analyzes the short-term current stress tolerated by the DC circuit breaker in the DC grid, proposes a test method and test circuit topology based on the loss and junction temperature equivalence are proposed, and builds a PSCAD/EMTDC electromagnetic transient simulation model. Taking the Kangbao Station of Zhangbei Project as an example, the short-term current withstand test of the DC circuit breaker was simulated and verified. The simulation results show that the test circuit can effectively implement the short-term current stress assessment of the DC circuit breaker. The design provides guidance for the test platform.