高压直流输电系统双极公共区保护若干问题的研究

Research on Several Problems of Bipolar Public Area Protection in HVDC Transmission System

高压直流输电系统双极公共区保护的动作直接影响到直流输电系统双极运行,甚至会造成直流双极强迫停运,给两侧交流系统安全稳定运行带来严重影响。本文结合案例分析了双极公共区保护存在的若干问题,包括:1)保护引入非电量信号的必要性及方式;2)中性母线接地开关(NBGS)开关动作策略;3)停运极进行注流试验时对运行极影响问题。根据分析结果,提出了双极公共区保护的改进方案,改进方案可提高保护运行的可靠性。目前,改进方案已在多个高压直流输电系统中实施,采用改进方案后,保护运行情况良好。

The bipolar public area protection action of HVDC transmission system directly affect the operation of bipolar system,or even cause bipolar forced outage,which has serious impact on the safe and stable operation to both sides of communication system.In this paper,the problems of bipolar area public protection is analyzed combining with actual events,including:1)the necessity and way of introduction of non-electricity protection signals,2)the action strategy of NBGS,3)the effect of flow injection test on the pole of outage to the operation pole.According to the analysis results,the improvement measures of protection is proposed.The measures can improve protection reliability.At present,the measures have been implemented in multiple HVDC transmission system,and the protection of HVDC transmission system operates well after adopting the measures.