A PC-Cluster-Based Fully Digital Real-Time Simulation of a Field-Oriented Speed Controller for an Induction Motor

Abstract

With the ever-evolving complexity of new adjustable speed drives (ASD) systems, maintaining the development and prototyping costs at reasonable levels is becoming more and more challenging for manufacturers of these equipment. Cost constraints have led design and test engineers to fully recognize the importance of real-time simulation, which is now widely used by high-tech industries as an essential and powerful tool to prototype complex engineering systems in a cost-effective and secure manner, while reducing the time-to-market. In this paper, the authors present a fully digital real-time simulation of a high-performance indirect field-oriented controller for an induction motor using RT-Lab™1 software package running on a simple off-the-shell PC. This real-time simulation tool is, for example like dSPACE™2 Real-Time Kernel, now adopted by many high-tech industries, particularly automotive and aeronautics industries, as a real-time laboratory package for rapid prototyping of complex control systems and for hardware-in-the-loop (HIL) applications. The proposed speed controller in indirect field-orientation for an induction motor is an adaptive IP controller. Its parameters are synthesized by considering possible variations in the rotor resistance. This parameter is estimated online and its actual value is supplied in real time to the speed controller, ensuring the robustness of the drive. Interacting in real time with the speed controller to test its robustness against the rotor resistance variations is not possible without real-time simulations. This achievement is, to the best of the authors' knowledge, reported for the first time in this paper and is believed to be an important contribution to rapid prototyping of high-performance induction machine controllers.