A new single-phase grounding fault location method of distribution networks with the influence of distributed generators and loads

Aiming at the single-phase grounding fault location problem of neutral point ungrounded distribution network system with distributed generators, a single-ended impedance method fault location method based on zero-sequence current is proposed. Firstly, the circuit voltage equation is written based on the line impedance parameters and the collected bus voltage, line bus current, end loads current and the distributed generator outlet current data, as well as the fault current series circuit voltage equation constructed by the zero-sequence component of the post-fault loads current, the zero-sequence component of the capacitor current to the ground and the zero-sequence component of the current at the head of the line. Secondly, the fault distance is given as a variable for the fault location equation of each line segment in turn, and finally the fault distance is obtained by solving the equation. In the process of fault location calculation, the problem of line-to-ground capacitor current compensation is considered, and the node voltage is used to calculate the capacitor current, the node voltage between the fault location and the bus end is calculated by the electrical quantity at the bus end, and the node voltage between the fault location and the end is calculated by the forward pushback generation method. An improved IEEE 34-node model with distributed power source and loads is constructed by PSCAD/EMTDC and the fault location simulation is verified, and the results show that the fault location of the distribution network with distributed generators and loads can be accurately located by the method proposed in this paper.