Impact analysis of network topology change on transmission distance relay settings

One big challenge raised by frequent topology change in today's power system is assessing the system protection security and dependability afterwards. This paper reviews the setting algorithm for the distance relays and proposes an automated setting calculation module. The calculation procedure is broken down into blocks which could be processed in parallel in order to improve the computation speed. The module could be used to assess the system protection vulnerabilities following a topology change in instances when multiple switching actions are done in response to occurrence of cascading faults or as a result of intentional control action. The module performance is tested on New England 39-bus and IEEE 118-bus systems. A sensitivity analysis in the form of N-2 contingency impact on the network relay settings is conducted on both test systems.