三种小电流接地系统选线算法及其仿真验证

Three Methods of Line Choosing Algorithm for Small Current Grounding Systems and Their Simulation Verification

针对小电流系统发生单相故障时单一选线法存在着一定动作死区问题,提出了相关系数选线算法、小波包多频带选线算法和小波包单频带极性选线算法。基于PSCAD/EMTD的35 kV系统模型的大量仿真数据显示,这三种选线算法不受各种过渡电阻、故障电压初始角和故障点位置的影响,能够正确选线。

Aiming at the shortage of the single line choosing method for small current grounding system,this paper puts forward three other line choosing algorithms,namely that using related coefficients,that using wavelet packet multi-band and that using wavelet packet single band polarity.The simulations on a model of PSCAD/EMTDC for a 35 kV system have been carried out in the paper,showing that the three line choosing algorithms can choose the right line in various conditions of the transition resistance,initial angle of breakdown voltage and fault location.