Using Phase Shifter and OLTC to Improve Reliability during Load Transferring and System Protection

Abstract

When the system requires reconfiguring or repairing, the load on one of distribution feeder needs to be transferred to another feeder without interrupting. However, there are several conditions which affects the load transfer on distribution feeder, including substation types, feeder loads, and primary side voltage of transformer. Those conditions will result in abnormal high current on load transferring, and the high current will lead to the operation of overcurrent relay. This paper uses ASPEN and Matlab/Simulink to simulate the load transfer of distribution feeder, and investigate the factor that will affect protection relay. An OLTC and a phase shifter is used to improve the high current during load transfer. It will avoid the action of protection relay, and improve reliability in power supply.