Design of an improved feeder self-healing control scheme

The logic processing course of both distributed mode and centralized mode for trunk line is introduced, and the advantages and shortcomings of two modes are also summarized. Because of the advantages and shortcomings of two modes for trunk line, an improved self-healing control scheme is presented and the use of IEC61850 standard for feeders self-healing application is taken into account. This scheme adopts the same logic processing course of fault diagnosis, fault location and fault isolation as the distributed mode. For the load in the offside of fault location, which has multiple power supply restoration ways, the method of implementing the defined plans is used for the fault processing procedure. Fault processing plans are defined in the master station in advance, and they are transmitted to the appropriate intelligent distribution terminal unit by IEC61850 communication protocol. During power supply restoration the intelligent distribution terminal unit perform the appropriate fault processing plan to the power supply for the load in the offside after it determines the current state of power grid. The improved self-healing control scheme possesses the advantages of both distributed mode and centralized mode, while avoiding their weaknesses. Theoretical analysis and engineering application indicate that improved self-healing control scheme presented has strong practicality in engineering.