Test plan automation for power transformer protective relay commissioning

The purpose of this paper is to present the implementation of a computer automated Test-Tool program that efficiently produces relay test plans to commission various microprocessor-based relays used to protect power transformers with and without low-side main breakers. The Test-Tool calculates the necessary currents, voltages and digital control conditions based on an automated read of a specific relay settings file. The Test-Tool is then used to interact with the software of a computer-operated test-set by first transferring this information to the test-set and then by acquiring the results of the tests and providing a customized report. This report presents and summarizes the technical information about the power transformer test procedures and its results. As well as being a quality control tool for consistent and thorough relay testing of power transformer installations, this Test-Tool can be used as training support material for new relay technicians and setting engineers.