Abstract:

In this paper, first, a nonlinear mathematical model of three-phase voltage source rectifier （VSR） with pulse-width modulation （PWM） is established in the synchronous rotating reference frame. Next, by considering the high coupling of active and reactive currents, a double closed-loop control algorithm of voltage and current is proposed, in which a sliding-mode control algorithm for the outer voltage loop and an exact feedback linearization method for the inner current loop are adopted. The whole system is then simulated, and the results are finally compared with those obtained by the traditional PI control. It is found that the proposed scheme integrates the advantages of sliding-mode control and feedback linearization method, which makes VSR to be robust and realizes decoupling control of active and reactive currents, and that, with the proposed scheme, the system is of high power factor, constant output voltage, good static and dynamic performance, and robustness to the disturbance and nonlinear variation of the load.

Key words: PWM rectifier, sliding-mode control, exact linearization, nonlinear control