Research On Leakage Protection Algorithm And Device In Mine Low Voltage Power Grid

Because of the particularity of the mine environment makes the weak fault signal, feature is not obvious, noise, leakage current fault line selection methods tend to mature, but there are still many deficiencies in positioning method of accuracy and reliability in practical application, omissions, false phenomena often occur, to ensure the safety and reliability of power supply, and quickly determine accurate fault location is very important.In order to improve mine safety as the starting point, for the long distance mine low-voltage electric network is analyzed the fault characteristics of single phase leakage, construct a new type grid structure by compacting three transformers based on zero sequence current logic relation and the zero sequence current transformer performance. With the artificial neutral point reactance grounding fault current to reduce the harm of compensation, are used relative entropy, differential eigenvalue concept and theory to analyze the leakage fault location, put forward the differential leakage fault line selection algorithm based on the concept of differential eigenvalue,and the leakage fault location algorithm based on wavelet packet energy relative entropy, and according to the structures of the algorithm process build the Matlab simulation models to analyse leakage fault, the simulation results show that:Two kinds of algorithms have their own characteristics,all can achieve the accurate positioning of the leakage fault. Under the laboratory environment to build simulation system based on the differential eigenvalue algorithm to design and develop the leakage protection device. The experimental results show that:The algorithm based on differential eigenvalue and its leakage protection devices can correct line selection, and consistent with simulation results.