Power-Electronics-Enabled Autonomous Power Systems: Architecture and Technical Routes

Abstract

Power systems are going through a paradigm change from centralized generation to distributed generation and further on to smart grids. In this paper, it is shown that future power systems will be power electronics based, instead of electric machines based, with a huge number of incompatible players and that the fundamental challenge behind this paradigm change is how to make sure these players could work together and maintain system stability. Then, a lateral architecture based on the synchronization mechanism of synchronous machines (SM), which has underpinned the growth and operation of power systems for over 100 years, is proposed to unify the integration and interaction of these players with the grid by operating power electronic converters to behave like virtual synchronous machines (VSM), which are coined cyber synchronous machines (CSM) here. Thus, all the suppliers and the majority of loads can follow the same mechanism to regulate system stability. This paves the way for autonomous operation of future power systems. Moreover, two technical routes, one based on the synchronverter technology and the other based on the robust droop control technology, are proposed to implement the architecture. Real-time simulation results are presented to illustrate the operation of such a system.