A New Representation based on Virtual Capacitor for Virtual Synchronous Generators

Grid-forming inverters will play a key role in the stability and operation of the future grid. Among different grid-forming methods developed in the literature, the virtual synchronous generator method (VSG) has become very popular due to the outstanding features it adopts from synchronous generators, like supporting the grid by inertia and autonomous grid-alignment. In this paper, a different representation for VSG is proposed by introduction of a “virtual capacitor”. It is shown that while the virtual capacitor shows the same performance as VSG, it gives a different physical representation that can be leveraged for design and study of multi-inverter systems. The simulation results corroborate the validity of the proposed method.