一起直流融冰装置阀侧避雷器爆炸故障分析

Analysis of an Explosion Fault of Arrester at the Value Side of the HVDC Ice-melting Device

本文以一起直流融冰装置避雷器爆炸故障为例,对生命周期内的避雷器动作及温度变化情况、控保系统动作情况进行分析,针对避雷器故障进行PSCAD仿真,分析故障原因为避雷器参数设计不合理,导致系统零功率试验解锁阶段电流断续产生的过电压超出设计允许值。在进行融冰试验后,避雷器多次导通并流经泄漏电流引起发热,由于累积效应造成热崩溃,进而导致爆炸。并提出避雷器选型及优化设计参数等改进措施,为今后类似问题提供参考方案,具有一定的工程意义。

An explosion fault of an arrester of the HVDC ice melting device is taken as an example to analyze the operation and temperature changes of arrester and the operation of control and protection system during its lifecycle.The arrester fault is simulated by PSCAD and the reason of the fault is analyzed.the result indicates that the parameter design of the arrester is unreasonable,which results in the overvoltage caused by intermittent current during the unlocking stage of the zero power test of the system exceeding the design allowable value.After the ice melting test,the repeated conduction and leakage current through the arrester caused heating and the cumulative effect caused a thermal collapse,which in turn led to the explosion.Improvement measures including the lightning arrester selection and the optimized design parameters are proposed,which provide reference solutions for similar problems in the future and have certain engineering significance.