Transient Analysis of Power Systems

4 Real-Time Simulation Technologies in Engineering

Christian Dufour and Jean Bélanger

4.1 Introduction

Real-time simulators have always been used to design and test control and protection equipment performance before their installation on actual power systems. Protection and control equipment was usually interfaced with analogue benches emulating the real power systems in order to perform tests under realistic steady-state and faulty operating conditions. Actual control systems as well as analogue benches were, by definition, operating in real time, meaning that control and protection systems under test were exchanging signals at the same speed as when the tested equipment was installed on the actual power systems. The same technique was and is still applied in all industries including automotive, aircraft and aerospace.

Over the past two decades, commercially available computers have become both increasingly powerful and more affordable. This, in turn, has led to the emergence of highly sophisticated simulation software tools enabling high-fidelity real-time simulation of dynamic systems, as well as of fast electromagnetic transients (EMT) expected in electrical and power electronic systems. The consequence is that several expensive analogue test benches and simulators have been replaced by more affordable, very flexible and accurate, fully digital real-time simulators (RTS). The RTS can then be connected in closed-loop with control and protection systems under design and ...