Fault Location Method in Active Distribution Network Based on Voltage Information of PQMS

In this paper, by establishing the Low Voltage Ride Through (LVRT) fault output model of Inverter Interfaced Distributed Generation (IIDG), the voltage information of the power quality detection device (PQMS) is used to establish the fault. Based on the location evaluation function, a new fault location method for an inverter-type DG distribution network is proposed. Firstly, the paper studies the low-voltage ride-through control strategy of inverter DG, establishes the fault characterization model of inverter DG, and analyzes the output characteristics under symmetrical and asymmetrical fault conditions. Then use the distribution network model with inverter type DG to analyze the fault characteristics under different fault conditions. By analyzing the fault component network, the equation of the node voltage with respect to the fault distance and the transition resistance is established, and the precise fault distance is solved by the improved particle swarm optimization algorithm. The method considers the influence of DG output characteristics on fault location of distribution network under fault conditions. Using the voltage information of PQMS, it solves the fault location problem of inverter DG active distribution network under low voltage ride through operation. Finally, an IEEE33 distribution network simulation system with inverter DG is built in DigSilent software to verify the effectiveness and accuracy of the proposed method.