针对矿山电网提出一种基于故障暂态电流主频分量的保护方案。分析了井下6/10kV配电线路的故障暂态电流主频频段.并在线路边界处并联通频带为该主频频段的带通滤波装置,利用该装置对通频带内暂态电流分量的衰减作用.强化区内、外故障时故障暂态电流主频频带内能量差异。利用PSCAD/EMTDC软件对所提方案进行仿真验证.并依据结果合理选择保护整定值。仿真结果表明:带通滤波装置使得区内、外故障暂态电流主频频带内能量产生了明显的差异:保护方案不易受故障类型、过渡电阻以及故障初相角的影响。
A kind of protection scheme based on the main frequency component of transient fault current is proposed for mine power network. The main frequency band of transient fault current of 6/10 kV distribution line for mine is analyzed and a corresponding band-pass filter is connected in parallel at the line boundary,which is used to attenuate the transient fault current components within that band for strengthening the difference of transient current spectrum energy within main frequency band between internal fault and external fault. The proposed scheme is simulated with PSCAD/EMTDC and the setting value is selected according to the simulative results,which show that,the spectrum energy difference between internal fault and external fault is obvious due to the fiher,and the prOposed scheme is immune to the fault type ,transition resistance and fault initial phase angle.