The comparative analysis of PI controller with PR controller for the single-phase 4-quadrant rectifier
The traction motor works as a inverter in regenerating mode, which achieves energy feedback with unity power factor. Though a proportional-integral(PI) controller is often used in traditional rectifier, bad tracking performance of sinusoidal input current is inevitable. A proportional-resonant(PR) controller resonates at fundamental frequency of input current to obtain a high gain, which can improve the tracking performance in rectifier. Based on analyzing the single-phase four-quadrant rectifier's principle, the mathematical model of ideal switch is established. A comparison is made between PI controller and PR controller for their effects to the rectifier. The results of this comparison show that the PI controller and the PR controller both can achieve good control effects. But the PR control structure is simpler and it can also improve the control accuracy. Besides, the PR controller is better than the PI controller at both sinusoidal reference tracking and anti-interference. The control theories above are successfully applied in control system of a single-phase four-quadrant rectifier. The simulation results prove the validity of the proposed PR control scheme.