中文摘要：

溪洛渡右岸送广东直流工程在孤岛运行方式下发生双回双极闭锁时,将在送端昭通换流站产生较大的过电压,其过电压水平以及交流滤波器断口和避雷器相应工况将决定孤岛运行的安全稳定性。为此,笔者结合溪右直流工程实际接线方式,分析了不同孤岛运行方式与滤波器配置方式,利用PSCAD/EMTDC,研究了双回同时双极闭锁（ESOF或BLOCK）、双回相继双极闭锁以及送受端交流系统故障情况下的昭通换流站交流侧的过电压水平与避雷器工况,针对采取切除小组交流滤波器和切除大组滤波器措施时,并考虑了一组切除时间早于其他小组半个周波情况,研究分析了断路器断口暂态恢复电压及容性开断电流对孤岛运行的影响。通过系统地仿真计算,研究结果为实际直流系统现场运行提供技术依据,对于孤岛运行故障的应对等具有重要的工程借鉴意义。

英文摘要：

With double-circuit bipolar trip of Xiluodu-Guangdong HVDC project in islanded mode, the overvoltage will occur to Zhaotong converter station as the sending power grid. Its overvohage level and the corresponding conditions of the AC filter and arrester will determine the safety and stability of islanding operation. Thus, with considering of practice connection mode, the different island operation modes and filter configuration are analyzed. The AC side overvoltage level and arrester working conditions of Zhaotong converter station are studied in case of double-circuit bipolar simultaneous trip（ESOF or BLOCK）, double-circuit bipolar successive trip and AC system faults in sending and receiving power grid by using PSCAD/EMTDC. For taking measures of cutting AC filter bank or group and considering the case of a group cutting half-cycle before the other, the effects of transient recovery voltage and capacitive breaking current of the AC filter breaker on the islanded operation mode are studied. Through the system simulation and comprehensive analysis above, it is of a certain engineering significance for providing the technical basis for the actual operation of the DC system site and dealing with islanded operation failure.