基于单片机的直流系统接地故障检测装置研究

Development of the DC system grounding fault detection device based on single chip microcomputer

直流系统常用于电力系统中,以实现对电力系统的控制和对自动装置的供电,而直流接地故障的频发会严重影响直流系统的可靠性,进而影响电力系统的安全与稳定,为此提出一种直流系统接地故障检测装置。在不平衡电桥的基础上,结合低频信号注入法提出了电桥参数设计方法以实现对电能参数信息的采集,并通过计算各支路的接地电阻值,完成对故障支路的定位,从而形成一个完整的直流系统接地故障检测系统。最后,设计了数字信号处理器DSP,对支路绝缘电阻进行实验分析,验证了直流系统接地故障检测装置的可行性,实现了对接地故障的准确定位,解决了检测死区与误报警问题,有利于电网的安全稳定运行。

DC system is often used in power system to realize the control of power system and power supply for automatic devices.The frequent occurrence of DC ground fault can seriously affect the reliability of DC system,and then affect the safety and stability of power system.Therefore,a DC system ground fault detection device is proposed.The DC system ground fault detection device proposes a bridge parameter design algorithm based on the unbalanced bridge and combined with the low-frequency signal injection method to realize the collection of electrical energy parameter information,and completes the location of the fault branch by calculating the grounding resistance value of each branch,thus forming a complete DC system ground fault detection system.Finally,the digital signal processor DSP is designed to carry out the experimental analysis of the branch insulation resistance,which verifies the feasibility of the DC system grounding fault detection device,realizes the accurate location of the grounding fault,solves the detection dead zone and false alarm problems,and is conducive to the safe and stable operation of the power grid.