一种混合直流真空断路器参数设计方法

Parameter Design Method of Hybrid DC Vacuum Circuit Breaker

为合理设计混合直流真空断路器各支路器件参数,以提升开断故障电流速动性及可靠性。本文首先针对自然换流阶段支路杂散参数及主回路电流上升率对转移速度的影响进行研究,确立了半导体开关型号及连接方式;随后通过LC单频振荡回路使半导体开关电流过零,为确保该强迫换流阶段半导体开关两端反向承压时间大于其固有关断时间使其够可靠关断,对换流电容和换流电感参数进行了优化;最后从吸能角度出发确立了压敏电阻特性参数。基于该设计方法进行了20kA电流等级试验并取得高效分断性能。

In order to rationally design the parameters of each branch device of the hybrid DC vacuum circuit breaker to improve the rapidity and reliability of the breaking fault current.This article first studies the effects of branch stray parameters and the main circuit current rise rate on the transfer speed during the natural commutation phase,and establishes the semiconductor switch model and connection method;Then,the LC single frequency oscillation circuit is used to make the semiconductor switch current zero.The parameters of the commutation capacitor and the commutation inductance are optimized to ensure that reverse withstand voltage time of the semiconductor switch during the forced commutation phase is longer than its solid-state off time,so that it can be turned off reliably.Finally,the varistor characteristic parameters were established from the perspective of energy absorption.Based on the design method,a 20kA current level test was performed and an efficient breaking performance was obtained.