Model Predictive Control of a Shunt Active Power Filter with Improved Dynamics Under Distorted Grid Conditions

This paper proposes a predictive control scheme for Shunt Active Power Filters (SAPF) that allows it to eliminate the harmonics and reactive current introduced by nonlinear loads. The active fundamental current component is accurately extracted by adopting Multiple Second-Order Generalized Integrators and Frequency-Locked Loop (MSOGI-FLL) techniques, even under highly polluted grid conditions. Based on this, a predictive current controller is designed to track the synthesized reference current with fast dynamics to realize unit power factor and very low total harmonic distortion (THD). Compared to the classical control method, the proposed method presents strong robustness to grid distortion. The performance of the proposed method is validated by means of hardware in the loop (HiL) tests to show its capability for solving the power quality problems.