直流输电系统接地极电流对交流电网的影响分析

ANALYSIS ON INFLUENCE OF GROUND ELECTRODE CURRENT IN HVDC ON AC POWER NETWORK

基于三广直流输电系统(三峡广东高压直流输电工程)的调试结果,分析了有多个直流系统落点的交流电网中直流接地极电流对交流电网影响的基本规律。提出为减小直流接地极电流对交流电网的影响应合理安排直流系统的运行方式;建立可靠的电流通道,减小接地极的接地电阻或建立专门线路;合理安排电网中交流变压器的接地点和接地方式。文章介绍了实施上述措施需进行的具体研究工作。

Based on the commissioning test results of the HVDC from Three Gorges hydro power station to Guangdong power network, the basic law of the influence of DC ground electrode current on AC power network, in which multi-HVDC receiving ends exist, is analyzed. To reduce this influence, it is necessary to rationally arrange the operating mode of the HVDC, build reliable current channel, reduce the grounding resistance of ground electrode, rationally configure the grounding points and grounding modes of AC transformers in AC power network, etc. The concrete study items of these measures to be performed are presented.