500 kV交流输变电工程启动调试中断路器分合分试验的探讨

在500 kV交流输变电工程建设后期的启动调试中，需要对500 kV空载线路进行至少3次单分单合的冲击合闸试验。然而，有些地区在成功进行了上述试验后，还要在500kV空载线路上进行若干次的断路器分合分试验。如果线路两端未装设合闸电阻和高压并联电抗器，在500 kV空载线路上进行断路器分合分试验具有一定的风险性。作者根据重合闸过电压的基本理论和一些现场实际经验证明了在特定条件下，分合分试验过电压在2~3 pu之间(1 pu= 550 kV)，证实了风险的存在，最后提出了规避分合分试验风险的建议。

Discussion on Opening-Closing-Opening Test of Circuit Breaker in Start-up and Commissioning of 500 kV AC Transmission System

In the start-up and commissioning at the later stage of 500kV transmission project construction, it is demanded to perform at least three times of the single-close-single-open impulse switching-in test for unloaded 500kV transmission line; nevertheless in some districts after successful execution of above-mentioned impulse switching-in tests, several times of opening-closing-opening test of circuit breakers are needed to perform for unloaded 500kV transmission line. If the closing resistor and the high-voltage shunt reactor are not equipped at both ends of the transmission line, there may be a certain technical risk for such a test. According to basic theory of overvoltage caused by reclosure and some on-site experiences, the authors prove that under specific condition the overvoltage caused by opening-closing-opening test of circuit breaker is within the range from 2.0 pu to 3.0 pu, thus the existence of risk is circumstantiated, and some suggestions to evade such technical risk are proposed.