断路器三相不一致保护可靠性分析及二次回路改进

摘要

介绍了断路器三相不一致保护的典型回路及其对电网安全稳定运行的影响,分析了断路器三相不一致保护回路的动作可靠性及影响因素.基于断路器三相不一致保护时间继电器性能测试试验结果,对三相不一致时间继电器的动作电压、动作时间进行详细分析.针对三相不一致保护回路继电器、接触器故障或时间继电器动作时间偏移导致保护不正确动作的问题,提出断路器三相不一致保护二次回路改进方法.针对三相不一致保护日常运行维护提出了相应管理措施.%The typical secondary circuit of three-phase inconsistent protection for a circuit breaker is described along with its influence on the safe operation of the power grid.Also, the action reliability of the protection circuit is analyzed.Based on the performance test results of the time relay for the three-phase inconsistent protection, the action time and the action voltage are thoroughly investigated.Then an improved secondary circuit of three-phase inconsistent protection is proposed to solve the incorrect operation problems of relay protection, which are caused by the relay failure, contactor failure, or action time migration of the time relay.Finally, several measures have also been proposed to enhance the maintenance of three-phase inconsistent protection.