Virtual synchronous generator grid-forming inverters based on model predictive control

The rapid increase in the share of renewable energy sources against conventional synchronous generators is challenging the grid. The falling number of synchronous generators reduces the rotating mass in the grid, worsening its capacity to ride through frequency and voltage disturbances. Virtual synchronous generator (VSG) is a promising solution for improving grid resiliency. With VSG technology, power electronic converters connect renewable energy sources to the grid by mimicking the behavior of traditional synchronous generators. This work enhances the current VSG technology by using a model predictive control (MPC) based approach. The aim is to provide effective real and reactive power support to the grid in the event of frequency and voltage deviations. The proposed MPC-based VSG is pulse width modulator free and does not require a phase-locked-loop in balanced grid conditions. Furthermore, the MPC-based algorithm is generic and can be applied to a large fleet of existing inverter topologies easily as it is simpler to tune than traditional controllers. The proposed system was simulated in MATLAB (Simulink) for frequency disturbances and grid voltage sag/swell events, and it was compared against the traditional VSG algorithm. The results obtained highlight that the proposed MPC based VSG supports the grid with lower power oscillations, fewer harmonics, and faster response times.