Accurate Fault Location Method of Distribution Network with Limited Number of PMUs

Accurate fault location of distribution network is of great significance for improving the reliability of power supply and reducing the loss caused by continuous power outage. However, due to the distribution networks have multiple feeders and shorter lengths of each feeder, which are different from the transmission network, making it more difficult to locate faults. In this paper, based on the characteristics of the distribution network, an accurate fault location method of distribution network is developed using limited number of synchronization phase measurement units (PMUs). The method including two steps: First, based on the distribution parameter model, after the faults happen, the voltage and current information from the PMUs installed at the end of the line will be collected to calculate the voltage at the headend of the branching point, if the fault line exists fault branch, the headend voltage of the fault branch will be abnormal. Then, the fault distance could be calculated based on voltage distribution along the two ends of the fault branch. The effectiveness of the proposed algorithm is verified by electromagnetic transient simulation. The simulation result shows that the proposed algorithm only use limited number of PMUs to locate fault accurately without the need of PMUs on both ends of lines, which is not affected by transition resistance and fault type. Ensuring high accuracy, the proposed method is also very economic and has well application prospects.