计及直流短路特性的单相故障换相失败免疫指标

Study on Immune Index of Communication Failure by Single Phase Failure Considering DC Short Circuit Characteristic

对电力系统最常见的单相故障,提出单相故障本地换相失败免疫指标和多馈入系统的换相失败免疫指标。在计算接地阻抗和短路电压的关系时,针对阻抗法未考虑直流系统短路特性的不足进行分析,提出基于交直流潮流的多馈入系统短路电压计算方法,以更加精确地得到临界阻抗。基于CIGRE-benchmark模型构建了三馈入系统,通过时域仿真结果、阻抗法计算结果和文中结果的对比,证明了所提算法的有效性和先进性。

The immune index of the local commutation failure and of the multi-infeed direct current（MIDC） system commutation failure against single phase fault are proposed. This paper analyzes the disadvantage of impedance method in short circuit voltage calculation, and puts forward the calculation method basing on the AC/DC flow. A three-fed system basing on the CIGRE-benchmark model is established. The effectiveness and advancement of the proposed algorithm is proved by the comparison between the results of the simulation and impedance method result.