Model-Free Predictive Current Control for Three-Phase AC/DC Inverters with LCL Filter Based on Hybrid SVM

The technology of space vector modulation has been commonly adopted in model-free method for AC/DC inverters based on LCL-type filter, which can achieve strong robustness against parameters disturbance and good steady-state performance. However, the grid-side current harmonics of model-free method with SVM is commonly higher than that of model-based method with SVM when accurate system parameters are known. To reduce the current THD while maintaining the strong robustness, an improved model-free method has been proposed in this paper, which adopts modified ultra-local model and hybrid SVM to reduce the steady-state harmonics of grid-side currents. The robustness and current harmonics reduction of the proposed method have been verified by the simulated results.