Modeling Predictive Control for the LCL Grid-Connected Inverter Fullyactuated System

In new energy grid connected power generation systems, compared to L and LC grid connected inverters, LCL grid connected inverters have superior high-frequency harmonic suppression capabilities. However, the LCL inverter is a third-order coupled nonlinear system, and traditional PI control is difficult to achieve optimal parameter tuning and solve its inherent resonance problem. The newly proposed all wheel drive control theory, starting from the physical laws of the system model, can simplify the design of controllers and effectively handle model coupling and nonlinear problems. Based on this theory, this paper derives a high-order fully actuated (HOFA) model for LCL grid connected inverters and proposes a HOFA control strategy to achieve fast and accurate control of grid connected currents. The grid connected converter model itself effectively solves the control problem of strong coupling and strong nonlinear systems. In order to avoid complex parameter tuning and improve dynamic response, a model predictive control (MPC) strategy is proposed to replace traditional PWM. The exported control strategy was validated through simulation, demonstrating enhanced dynamic response and reduced design complexity, providing an optimized solution for renewable energy system inverters.