Over Current Relay Modeling using Modelica with Cross-Verification against a Validated Model

Relays are one of the most important elements for power systems protection. In this paper, an over current relay model is implemented in the Modelica language. Once all of the different modules were tested individually, the modules would be integrated to the relay model which then would be subjected to different fault simulations. Thereafter, the different types of relays were implemented and the Modelica model results are compared to a Simulink model previously implemented. Finally, a sample power system was implemented in order to evaluate the relays performance in a system. The results show how effective the relay model is and lays a foundation for further fault simulation, real-time simulation and model exchange.