Virtual Synchronous Machines A unified interface for smart grid integration IMAGES LICENSED BY INGRAM PUBLISHING, MICROGRID IMAGE-©ISTOCKPHOTOCOM/9AMSTOCK, COMPUTER IMAGE-GRAPHIC STOCK by Qing-Chang Zhong Digital Object Identifier 10.1109/MPEL.2016.2614906 Date of publication: 20 December 2016 18 IEEE POWER ELECTRONICS MAGAZINE P ower systems are going through a paradigm change from centralized generation to distributed generation and further on to smart grids. More and more renewable-energy sources, electric vehicles, energy storage systems, and so forth are being connected to power systems through power electronic converters. Moreover, the majority of loads are expected to connect to the grid through power electronic converters as well. This article shows that these converters, either on the supply side or on the load side, can all be controlled to behave like virtual synchronous machines (VSMs) and possess the dynamics of synchronous machines, providing a unified interface for smart grid integration. Synchroconverter technology and its developments are the focus of this article because the mathematical model of synchronous machines is embedded in the controller of synchronverters to provide close imitation. z December 2016 2329-9207/16©2016IEEE