交直流混联系统故障暂态过电压研究与仿真分析

Research and Simulation Analysis of Transient Overvoltage Caused by Faults in AC-DC Hybrid Systems

摘要: 针对交直流混联电路发生直流闭锁，换相失败和交流故障时对送端交流电压产生什么影响的问题，采用了pscap和pscad仿真的方法进行模拟，发现在直流双极闭锁故障下，送端交流电压不会下降，而是呈现过电压；在换相失败故障下，送端交流系统电压非常迅速地先下降，后恢复，直至产生过电压，最后恢复稳态；在发生交流故障后，送端交流电压先骤降，后恢复至稳态。

Abstract: In order to solve the problem of the influence of DC blocking, commutation failure and AC failure on the AC voltage at the sending end in the AC-DC hybrid circuit, pscap and pscad simulation methods are used to simulate the problem. It is found that under the DC bipolar blocking fault, the AC voltage at the sending end does not drop, but presents overvoltage. In the case of commutation failure, the voltage of the AC system at the sending end drops first, then recovers very quickly until overvoltage is generated, and finally returns to steady state. After an AC fault occurs, the AC voltage at the sending end first drops sharply and then returns to steady state.