Linear control design for a current-injection-based three-phase unity-power-factor rectifier

In this paper, a new control strategy based on the pulsewidth-modulation technique is proposed and applied to an active-current-injection-based unity-power-factor three-phase ac-dc converter. The control circuit of the converter consists of a multivariable inner current regulator and an outer voltage regulator. Based on linear control techniques, the control circuit has been designed. Averaging techniques are used to derive a linear small-signal model of the converter in the frequency domain. Numerical simulations using the Power System Blockset tool of Matlab/Simulink highlight the performance of the proposed control scheme. Experimental results obtained on a 2-kW prototype validate the theoretical approach described in the paper.