基于DSP的低压配电线路电弧故障检测系统

摘要

The characteristics of arc⁃fault on low voltage distribution lines are experimentally researched in this pa⁃per. And the Mallat algorithm is appointed to decompose arc fault current on low voltage distribution lines, and the obtained detail components are compared in different scales with normal current to establish characteristic quantity. The experimental results show that arc fault detail components drastically ascend as compared with normal current, in addition the high scales detail components play part in noise elimination. Eventually the comparison between arc fault current and start current in detail components aiming at avoiding misjudgment shows that multi scale wavelet a⁃nalysis Mallat algorithm is effectively used to detect arc fault. According to the above, an arc fault detection system based on DSP ( Digital Signal Processor) is developed in this paper and a method of adaptive fault diagnosis is pro⁃posed, the experimental results show that the method will detect arc⁃fault effectively combining with the Mallat algo⁃rithm.%通过实验模拟对低压配电线路电弧故障的特征进行分析研究，采用Mallat算法对低压配电线路电弧故障电流实施变换，获得各尺度小波变换的小波分量。与正常运行分量相比其故障特征明显，且高尺度的小波分量还可以抑制噪声干扰。为了避免配电线路中负载的启动电流对电弧故障检测产生可能的误判影响，本文采用多尺度小波变换有效地实现了电弧故障与负载启动电流的区分判别。在此基础上，本文开发了基于DSP微处理器的电弧故障检测系统，并提出了一种自适应的故障特征提取方法，实验结果表明，该方法结合Mallat算法可有效地诊断电弧故障。