摘要
通过对一起发变组保护误动事故的调查分析,发现其直流控制回路的电缆过长,分布电容过大,当交流串入直流系统时,会通过控制电缆的分布电容构成回路,产生电容电流,引起一些动作值较低的灵敏继电器发生误动作,并据此提出了防范措施。通过改进继电保护二次回路,提高非电量保护启动功率,缩短直流控制电缆的长度,避免了此类问题的重复出现。
Through the investigation on the accident resulted from generator-transformer unit misoperation, find that the length of the cable in protection loop is too long and the distributing capacitance of the cable is too big. When the severe mutual interference between DC and AC circuits effects as DC grounding, the sudden discharge of distributed capacitance, as a disturbance source, activates the output relay. Countermeasures are suggested, shorten the length of DC control cables, increase the voltage of intermediate output relay and breaker trip coil, avoid the repetition of such problems.
出处
《能源研究与管理》
2014年第3期49-51,共3页
Energy Research and Management
关键词
交直流串扰
保护误动
分布电容
控制电缆
直流回路
非电量保护
发变组
AC-DC interference
misoperation
distributed capacitance
control cable
direct current circuit
non-electricalprotection
generator-transformer unit
