Transient energy based directional detection for series compensated parallel lines

This paper presents a newly developed directional detection solution based on fault induced transient energy. The solution has been used for heavily series compensated parallel lines as directional units to enhance permissive overreach transfer tripping (POTT) scheme as the redundant protection function in actual 525 kV transmission networks. This paper starts with introduction of transient energy based directional detection method and advantages first. Then the paper describes the technical principle of the directional detection concept and proposes a new solution of transient energy direction detection suitable for series compensated line conditions. In order to verify the solution, site records and simulation tests have been used to verify the new solution. The actual site test example of POTT scheme based on the proposed solution is given further. Finally the conclusions are provided by confirming the performance of the new solution with both good dependability and security for series compensation protection application conditions.