短路故障相控限流策略及效果分析

Analysis ofPhase-controlled Current Limitng Strategy for Short Circuit Fault and Its Effect

针对故障限流器换流过程的过电压暂态冲击问题,提出短路故障相控限流策略,为此,在阐述短路故障相控限流策略原理的基础上,对关键技术——短路电流快速辨识算法进行仿真和比较分析。优选基于改进递推最小二乘法(recursive least square, RLS),并对其性能进行了仿真分析;对短路故障相控限流(controlled fault current limiting,CFL)方式和直接故障限流(directly fault current limiting,DFL)方式的燃弧时间、电弧能量及换流时间进行对比、仿真分析。所得结果表明CFL方式相对于DFL方式,燃弧时间短,电弧能量低,能够减小触头烧蚀,更有利于限流器换流使用。

Aiming at the problem of overvoltage transient impulse in the process of commutation of the fault current limiter, the paper proposes a phase-controlled current limiting strategy for short circuit fault. On the basis of stating strategy principle, it makes simulation and comparative analysis for the key technology called the fast identification algorithm for short circuit current. It gives preference to the adaptive recursive least square (RLS) algorithm and makes analysis for the performance. Meanwhile, it compares and analyzes arc time, are energy and commutation time of the controlled fault current limiting(CFL) mode and the directly fault current limiting(DFL) mode. The results obtained indicate compared to the DFL mode, arc time of the CFL is shorter and arc energy is lower, which means this mode can reduce contact ablation and is more beneficial for the current limiter.