METHOD AND DEVICE FOR ESTIMATING ANGLE OF ZERO-SEQUENCE VOLTAGE IN SINGLE-PHASE EARTH FAULT

摘要

Embodiments of the present disclosure provide a method and a device for estimating an angle of a zero-sequence voltage when a single-phase earth fault occurs in a distribution network with decentralized generating devices. The method for estimating an angle of a zero-sequence voltage comprises: detecting angles of respective phase voltages in three phase voltages; determining a neutral earthing type of the distribution network; and estimating the angle of the zero-sequence voltage when the single-phase earth fault occurs in the distribution network with the detected angles of the respective phase voltages, according to the neutral earthing type of the distribution network. The angle of the zero-sequence voltage may be estimated with the angles of the three phase voltages provided by the existing VPIS without accurate magnitudes of the three phase voltages, so that the detection for the single -phase earth fault is simpler and easier, and the cost of the earth fault detection device is reduced.