Deadbeat control scheme for three phase current-fed PFC converter with an optimum PWM strategy

A novel deadbeat control of a three-phase current-fed PFC power converter with an optimum PWM pattern is presented to improve its dynamic state performance. In order to improve the utility-side current THD characteristics of this converter, the feasible optimum PWM pattern under conditions of lower switching frequency for large capacity applications is introduced. By using a moving-average that provides a digital filter function for measured variables, the ripple component of carrier frequency can be removed. This deadbeat control scheme with proposed optimum PWM for current-fed three-phase PWM converter could be successfully applied to improve the transient response of utility-power source line current. It is proven from a simulation point of view that sinewave line current shaping can be achieved for a three-phase current source converter operating under unity power factor and proposed control system provides a fast transient response.