Development of a hybrid emulation platform based on RTDS and reconfigurable power converter-based testbed

A real-time hardware testbed (HTB) has been constructed to emulate the power system by modular regenerative converters. This allows system realistic testing and demonstration with the true measurement, communication, and control. However, the size of the system that can be emulated by the HTB is limited, and certain phenomena are not easy or not needed to be modeled in the HTB. A hybrid emulation platform, which combines real time digital simulator (RTDS) and HTB, is developed in this paper to complement the advantages of RTDS and HTB. A power electronics converter is designed to act as the power interface between the RTDS and the HTB, and an integrated interface with two complementary algorithms is implemented to realize the hybrid emulation stably under different system conditions. At the same time, the closed loop control method under dq0 axis is implemented to realize faster response characteristics, and a time delay correction algorithm is integrated into the Park transformation. Experiment results demonstrate the performance and effectiveness of the hybrid emulation compared with the pure HTB emulation and digital simulation.