Technology and application of high speed fault location,isolation and self-healing in DC distribution network

With the continuous increase of DC load, the research of DC distribution network has been developed rapidly. Compared with the traditional AC distribution network, DC distribution network has the advantages of less conversion times, high efficiency, low cost, simple control structure, no need to consider the frequency and phase and reactive power compensation equipment. Compared with AC distribution network, DC distribution network has more flexible operation mode and less power supply points However, the more flexible operation mode of DC distribution network also brings the problem of fault location and self-healing. The fault location, isolation and self-healing control strategy of AC distribution network can not be applied to DC distribution network. In this paper, a high-speed fault location, isolation and self-healing method for DC distribution network is proposed. Based on high-speed goose communication, a comprehensive evaluation is carried out according to the fault status of the power grid, and the millisecond level fault location, isolation and self-healing of DC distribution network are completed. The coordinated control equipment based on this method is successfully applied in Tongli integrated energy service center. When the fault occurs in this area, uninterrupted power supply is realized in the non fault area, which verifies the correctness and practicability of this method.