交直流互联电网暂态功率倒向及对继电保护的影响

Transient Power Converse in AC/DC Interconnected Power Grid and Its Influence on Protective Relaying

由于交直流系统的相互作用,在交流输电系统中出现暂态功率倒向并导致纵联方向保护误动事件的实例已经出现。基于国际大电网会议(CIGRE)直流输电标准测试系统,研究当逆变侧交流系统故障时,直流输电系统的响应特性及交流输电系统的故障电气特征。分析了交直流互联电网环境下,在交流系统故障的暂态过程中暂态功率倒向的机理、交流故障特征量的变化及对继电保护的影响,并提出了可采取的技术措施。

Several incidents of transient power converse due to the interaction of AC/DC system have been reported recently, that led to the real-operations of directional pilot protection in AC transmission systems. Based on CIGRE HVDC Benchmark Model, the response characteristics of HVDC transmission systems and the fault features of AC transmission systems are studied in this paper when faults occur at the inverter side AC system. The mechanism of transient power converse, the variations of AC fault features and their influence on protective relaying during the transient processes of AC system fault are analyzed. Also, some technical measures are put forward.