A Hierarchical Minimum Hitting Set Calculation Method for Multiple Multiphase Faults in Power Distribution Networks

In this article, model-based diagnosis (MBD) is an important fault diagnosis method for power distribution network faults. The minimum hitting set (MHS) calculation, as one of the steps of MBD, has a significant impact on the performance of MBD. However, the efficiency and accuracy of MHS calculation limit the performance of MBD when the distribution network has multiple multiphase faults. To overcome these limitations, a hierarchical MHS calculation method for multiple multiphase faults is proposed. This method first converts a single high-dimensional MHS calculation into multiple low-dimensional MHS calculations by establishing a hierarchical MBD. In the low-dimensional MHS calculations, the fitness function and MHS criterion of the MHS calculation are improved to enhance the versatility of the method for different minimum conflict sets, and the exhaustive method is used instead of the intelligent algorithm to realize the search process. Finally, a 14-node distribution network is taken as an example to verify the advantages of the hierarchical MHS method in terms of calculation efficiency and accuracy under multiple multiphase faults.