Versatile static synchronous machine and its reference machine following control strategy

Abstract

In the construction of the new-type power system, inverters with the synchronous machine characteristics are required. Here, the versatile static synchronous machine (VSSM) and its reference machine following control strategy are proposed. By integrating the battery energy storage system (BESS) into the modular multilevel converter (MMC), the VSSM has more operational flexibility than a conventional synchronous generator. Then, the basic theory of the reference synchronous machine is discussed, indicating that the VSSM can acquire the synchronous machine characteristics by following the operation of the reference synchronous machine. Based on the above principle, the implementation of the reference machine following control strategy is presented, including the synchronous machine mode and the current limiting mode. The case studies are performed on a 2-area test system and a modified IEEE 39-bus test system by time-domain simulation in PSCAD/EMTDC. The simulation results verify the synchronous machine characteristics in the proposed VSSM with the machine following control, and sheds some light on the potential of the VSSM in the new-type power system.