Real-time Hardware-in-the-loop Implementation for Power Systems Protection

Nowadays real-time simulation (RTS) systems are becoming a must-have within every power system lab. This as a result of new participants in both ends, providers as well as users, entering into this market which have lowered the price of such systems. This has allowed the proliferation of implementations based on the Hardware-in-the-loop (HIL) paradigm which insert a hardware component within the control loop, replacing either the plant or the control block (or part of the whole block). Thus, this paradigm provides a more reliable and efficient way for the development of the protection and control for power systems.This contribution presents a Real-time hardware-in-the-loop implementation for power systems protection. The implementation is carried out on the OPAL-RT platform based on Matlab (R) & Simulink (R) and the SEL-351 protection system. The power system is modeled and assembled using Simulink (R). Then, the model is ported on OPAL-RT, where its digital/analog inputs and outputs are used for interacting with a digital relay and its own digital outputs. Thus, the relay provides trips due to over-current and over-frequency avoiding the evolution of the faults. The main contribution of this paper is the incorporation of a physical protection device within the control loop of a simulation testbed power system whose results confirm the performance, precision, and reliability of the protection scheme.