Real time emulator of static converters/electrical machines application to the test of control unit

In this paper, a static power converter/electrical machine emulator is presented. The basic concepts that have led to its design are discussed. Two simulation technologies are studied: numerical; and analog. The numerical simulation allows the development of a universal emulator. However it is limited by the synchronization problem and the limitation of the classical computer performances. Analog simulations always have the performance capacity of real-time simulation. However, they are limited in precision and flexibility. According to the above considerations, a compromise is taken and the authors present a hybrid structure for the emulation system. For every part of this system, a proper description is furnished and the corresponding circuit is presented. The emulator is used to test digital control units. It replaces the physical process, making the control unit believe that it is connected to the real device. Thereby, after the emulation step, the control device is ready for direct use on real systems, without any modifications. To illustrate these purposes, an application example of the emulator on a DC machine is presented.