基于STM32的故障电弧检测装置设计

检测负载电流信号特征是判断低压配电线路中是否发生电弧故障的有效方法之一。依据国家标准GB/T 31143-2014《电弧故障保护电器(AFDD)的一般要求》，搭建模拟串联故障电弧实验平台，研究故障电弧发生时电流波形的特征，并采用db4小波函数作为小波基函数，对降噪后的电流波形进行小波分解重构，提取小波高频分量，计算小波高频分量的周期方差值，将周期方差值作为主要特征值来进行电弧故障检测；为了在硬件上验证该检测算法的可行性和有效性，将电弧故障检测算法移植到STM32平台，设计了基于STM32的故障电弧检测装置，该装置可以实现电流信号采集、数据处理和串联电弧故障检测识别功能。在以阻性负载、LED灯、吸尘器和微波炉为屏蔽负载的实验结果表明，该装置能够检测出串联电弧故障，且可靠性高，不会在没有产生故障电弧的情况下产生误判。

Design of fault arc detection device based on STM32

The detection of the load current signal is one of the effective methods for judging whether an arc fault occurs in the low-voltage distribution line; according to the national standard GB/T 31143-2014 "General Requirements for Arc Fault Protection Devices (AFDD)", the analog series fault arc is built. The experimental platform studies the characteristics of the current waveform when the fault arc occurs. The db4 wavelet function is used as the wavelet basis function to decompose and reconstruct the current waveform after noise reduction, and extract the wavelet high-frequency component, calculate the periodic variance value of the wavelet high-frequency component, and detect the arc fault according to this value; The feasibility and effectiveness of the detection algorithm are verified. The arc fault detection algorithm is transplanted to the STM32 platform, and the fault arc detection device based on STM32 is designed. The device can realize the functions of current signal acquisition, data processing and series arc fault detection and recognition. Experiments with resistive loads, LED light, vacuum cleaners and microwave ovens have shown that the device can detect series arc faults with high reliability and will not cause false positives without generating fault arcs.