20kV电网电压暂降及其应对措施研究

Research on Voltage Sag of 20 kV Power Network and Countermeasures

电压暂降是影响电网电能质量的重要问题之一,对电网的安全稳定运行和用户的可靠供电均会产生不利影响。嘉兴电网20 k V试点区电网运行实践表明,20 k V电网电压暂降现象比10 k V电网更严重,尤其是在20 k V母线或出口短路时,引起上一级电网电压暂降造成的危害更大、影响范围更广。通过计算分析了影响电压暂降幅度的因素,研究相应的应对方法,并提出缓解电压暂降的措施。

Voltage sag is one of the significant problems affecting power quality of power grid and has adverse effect on operation safety and stability. Operation practice of 20 kV network in Jiaxing pilot area indicates that 20 kV power network voltage sag is more serious than 10 kV network; especially when a short circuit hap-pens on 20 kV bus or its exit, the resulting voltage sag of upper-level power grid causes greater harm and wider influence range. by the impact of a wider range. Through calculation the paper analyzes factors affecting the magnitude of the voltage sag, explores appropriate countermeasures and proposes voltage sag mitigation measures.