光伏系统直流串联故障电弧特征研究

摘要

Based on the combination of time domain analysis and frequency domain analysis,the series arc fault in photovoltaic (PV) system is studied.A new type of PV system fault arc test platform was set up,the differences between the peak-to-peak current and the current average in normal operation and series fault arc were acquired,the feasibility of the current time domain feature in the identification of series fault arc was analyzed.The conclusion is that one-level wavelet decomposition detail component mean value of series fault arc current is 2.5 ～4 times that of the normal state,two-level is 10 ～ 16 times that of the normal state.The above conclusions can be used to form the series arc fault identification criterion through effective data fusion,and provide theoretical support for the development of series arc fault protection devices in PV system.%应用时域分析和频域分析相结合的方法,研究了光伏系统串联电弧故障问题.搭建了新型光伏系统故障电弧实验平台,获得了光伏系统正常运行和发生串联故障电孤时电流峰峰值和电流平均值的特征差异,分析了电流时域特征在串联故障电弧识别方面的可行性.得到了光伏系统发生串联故障电弧时,电流一层小波分解细节分量均值是正常状态下的2.5～4倍,两层小波分解细节分量均值是正常状态下的10～16倍的结论.以上结论可通过有效的数据融合形成串联电孤故障识别判据,为光伏系统串联电弧故障保护装置的研制提供理论支持.