Busbar Differential Protection System Testing Based on Practical Considerations Using Real-Time Digital Simulator Hardware-In-the-Loop Technique

In this study, we proposed a hardware-in-the-loop (HIL) testing technique that is unique in the following manner. 1) The power system network used as the base for testing the protection system is suitable for the study since it is a transmission network. 2) Simulation studies were carried out before configuring the proposed protection system to ensure that the power system network’s initial conditions comply with the system’s requirements for use in the study. 3) Lastly, the methods used to select instrument transformers and relay protection elements are done according to the standards. The method of testing in this study has proven that it is possible to run normal system conditions and use the developed protection system for monitoring these conditions. This has been proven by simulating normal system conditions while tracking the differential and restraint currents using the SEL-487B Protection System Automation. The testing procedure used in this study can be used in the industry to test various protection systems for all conditions rather than focus on the elements of the protection system.