【摘要】 防止电力系统母线发生区外短路故障时 ,由于电流互感器 ( TA)饱和造成的电流瞬时值差动母线保护误动作 ,一直是母线保护中的一个重要课题。文中根据母线发生短路故障时 ,电流互感器饱和具有滞后的特点 ,提出了一种应用小波变换原理提取故障电压暂态特性 ,准确检测故障发生时刻 ,并根据时差法的基本原理来确定 TA是否饱和的新方法。仿真结果证明了所提方法的有效性。更多还原

【Abstract】 Differential bus protection with instantaneous current value is easily influenced by saturation of currenttransform er to mal- operate. Based on the lag characteristic of saturation of current transformer when short- circuit occurs,this paper proposes a m ethod for analyzing the transient voltage of the faulty bus by the wavelet transform,then detecting accurately the fault point.The saturation of current transformer can be distinguished based on the time difference between the tim e of the fault and the time of differential current.The simulation results show the effectiveness of the proposed method.更多还原