An interface for switching signals and a new real-time testing platform for accurate hardware-in-the-loop simulation

Testing digital control systems for power electronics applications is an intricate procedure. An effective tool for the evaluation of electric systems and drives is provided by real-time hardware-in-the-loop (HIL) simulation, which is being increasingly used in industrial applications. However, to be practical, the real-time simulation platform must be inexpensive and easy to set up for various tests. In this paper, virtual test bed (VTB) and its real-time extension (RTVTB), in conjunction with a custom hardware interface, are utilized to implement an affordable and versatile real-time testing platform for digital controllers. The hardware interface addresses the timing issues introduced by the presence of switching circuits in the system under test. Integrating the switching gate control signal, which comes from the hardware digital controller, requires very high time resolution. However, such high resolution is not necessary to accurately simulate the electric system under control. The proposed hardware interface separates the hardware requirements from the real-time simulation requirements in terms of time resolution, maintaining appropriate accuracy in the testing procedure.