Model Predictive Control-Based Virtual Inertia Emulator for an Islanded Alternating Current Microgrid

Conventional primary control employs outerloop droop and inner-loop cascaded linear control to realize local voltage regulation and power-sharing of an islanded ac microgrid.However, it has a complex structure, limited dynamic response and a rapid rate of change of frequency when disturbances occur.This paper resolves these issues by proposing a model predictive control based virtual synchronous generator (VSG-MPC).An improved finite-set MPC is first proposed for the inner loop, achieving simplified control structure, faster dynamic response, enhanced bandwidth and stability, as well as improved current limitation.In the outer control loop, a simplified VSG without a phase-locked loop is employed to realize active powersharing and inertia emulation.The merits above are verified by a description function of MPC and the frequency-domain response of the overall VSG.Simulation and experimental results verify the feasibility of the proposed method.