Extending the VISMA concept to improve the frequency stability in Microgrids

Current electrical power systems are undergoing a transition process from the centralized generation paradigm to a decentralized one. In this sense power electronics can be seen as the key connecting both paradigms. However, the great deployment of power electronics also implies a negative impact on the grid dynamics. The main cause is represented by the reduction of inertial response. This paper presents the design of a control strategy based on the virtual synchronous machine concept to improve the incorporation of converter-coupled units. The application of this concept is extended to controllable and non-controllable generation as well as loads. The proposed control shows a great potential to improve frequency stability in systems with high penetration of power converters, especially in weak electrical systems such as Microgrids.