Nonlinear PR control strategy for cascaded H-bridge rectifier based on state feedback linearization

A nonlinear proportional resonant (PR) control strategy is presented for single-phase cascaded H-bridge rectifier in this paper. By using state feedback linearization (SFL) technique and linear quadratic riccati method, the proportional control loop is constructed and tuned. To achieve zero phase' tracking of sinusoidal grid current, a resonant transfer block is added, which forms a PR control frame. The new PR controller features of global stability and more simple and clear parameter tuning process. Experimental results show that the proposed control strategy guarantees fast regulation and stability of sinusoidal grid current and dc voltage, meanwhile achieves unity power factor.