The Design And Implementation Of Ground Fault Detection In DC System Of The Substations In District

As the main direct-current suplument of secondary device in substation, the direct-current system plays an inportant role in the safely operation of substation. In the practical substation, the DC system also happened to some fault which affect the security operation of other device, among which ground fault has the highest probility, and it’s various and complex. At the same time, the level of ground insulation has the trend of decreasing after years of actual operation. Once occur to the situation that two-point grounding, the maloperation will be caused. Thus, it has great project application value to research and develop.This dissertation introduces some kinds of methods to detect insulation in DC system, and analyzes their merits and demerits in detail. On the basis of these analysis, the basic insulation theory and blue print of the system design are proposed. The implementation method has been described respectively in hardware and software.Ground Fault Detection in DC System uses modular design concept. The detection system is broken into sampling circuit, power module, reset module, insulating sensor and CAN bus module based on the C8051F040. Varies modules coordinate with each. Based on the hardware design, analyze the software function, The system has been operating in Baoquanling Substation. After testing the system, it declares that the system can find the fault in the DC system directly and accurately, inproves the substation system’s operation stability and security.