Realization of the ground resistance detector based on different frequency signals in DC system

Several of the conventional ground resistance measurement methods such as AC method, DC leakage method etc. and their shortages are discussed. A new kind of ground resistance detector in DC system is presented. The detector, with C8051F041 as kernel, adopts measurement method basing on different frequency signals. The proposed method can reduce impact of branch distributing capacitor on ground fault location and improve the measurement sensitivity and precision of ground resistance. The principles, hardware and software design are introduced emphatically. The experimental results and practical operations show that the new method for insulation detection and ground fault location are very valid and reliable.