天广直流金属/大地回线转换不成功原因分析

笔者分析了天广直流控制保护系统改造后系统调试过程中极1金属回线转大地回线不成功的情况,结合金属回线开关保护配置和原理,通过分析故障时动作录波和线路电流,对金属回线开关进行测试,得出试验中金属回线开关保护动作原因为金属回线开关的谐振回路避雷器绝缘缺陷,并提出每年直流停电检修期间,对转换母线设备绝缘进行预防性试验的建议。

Analysis of an Unsuccessful Conversion from Metallic Return to Ground Return in Tianshengqiao-Guangzhou HVDC System

An unsuccessful conversion from metallic return of pole 1 to ground return in debugging phase after reform of Tianshengqiao-Guangzhou HVDC control and protection system is discussed.The waveform record and the line current at the fault moment are analyzed,and the metallic return switch(MRS)is tested by considering the protection configuration and principle of MRS.The result indicates that insulation defect of the arrester on the resonance circuit of MRS causes protective action of MRS in test.Correspondingly,preventive test for insulation of conversion bus equipment is suggested during annual outage for maintenance.