With the development of distribution network,its scale is getting larger and larger,and its structure has become complex and diversified.Therefore,more attention has been paid to the safety,reliability and economic operation of distribution network.The distribution network operation is affected by the real conditions,and high impedance faults occur when contact with high impedance material.When the fault occurs,the fault current is weak and the waveform characteristics are not obvious,so the conventional protection device can't accurately remove the fault.The fault is often accompanied by harmonic and arc phenomena,which will lead to new fault points and further expand the accident if it exists for a long time.In this paper,the HHT band-pass filter is used to process the three-phase voltage and zero sequence voltage of the bus,and to construct the time-frequency energy spectrum of block.After processing,it is input into deep belief network for training and classification.The simulation model established in this paper proves that this algorithm has high accuracy.
