Novel Differential Protection for Distribution Network Feeders with Intermediate Loads

As the fault characteristics in distribution feeders become increasingly complex, differential protection is believed a feasible method. When there are intermediate loads inside the distribution network feeder, existing methods must increase the operation threshold to prevent protection maloperation. However, this will sacrifice the performance of differential protection. To overcome this issue, this article proposes a novel differential protection method suitable for distribution feeders with intermediate loads. This differential protection only requires the data at both ends of the protected section, without the need for real-time measurement data of intermediate loads. The simulation results based on PSCAD/EMTDC reflect that the proposed novel differential protection is not subject to the intermediate load capacity and can correctly judge fault section when different types of faults occur, with high reliability and sensitivity.