Circuit and Control Scheme of Converter-Based Emulation for Control Testing of AC Microgrid

Due to the fast development of renewable energies, the microgrid has been proposed as a novel configuration of modern power grids integrated with a large number of grid-connected converters. To achieve flexible functions in microgrids, various control schemes are implemented in the grid-connected converters and play a vital role in the operation of the microgrid. In this case, the emulation of the microgrid is becoming an emerging need for the testing of AC microgrid controls. However, the conventional emulation approaches are cost and bulk in the emulation of microgrids with complex configurations. In this paper, a novel emulation system is proposed for the test of various AC microgrid control schemes. a low-cost circuit configuration, which includes two face-to-face-connected DC-AC converters and some passive loads, is introduced with the possibility to recreate most of the fundamental control schemes in a typical AC microgrid. Besides, different types of control schemes are implemented in the two converters to flexibly recreate the corresponding control behaviors.