Three-phase PWM boost-buck rectifiers with power-regenerating capability

Three-phase pulsewidth-modulated (PWM) boost-buck rectifiers with power-regenerating capability are investigated. The converters under consideration are capable of: 1) both voltage step-up and step-down; 2) bidirectional power processing; and 3) almost unity-power-factor operation with nearly sinusoidal ac current. Expected advantages are: 1) applicability to lower voltage applications, e.g,, direct retrofit to replace diode or thyristor rectifiers; 2) switching loss reduction in the inverter load; 3) low-order harmonic control in the inverter load output voltage; 4) blanking time effect mitigation in the inverter load; and 5) a modest level of voltage sag/swell compensation. In this paper, firstly, a step-by-step power stage derivation process is described. Then, taking the Cuk-Cuk realization as an example, its operating principle and modulation scheme are described. A steady-state model and dynamic model for controller design are also described. Representative results of circuit simulations and hardware experiments are presented. Through these procedures, the feasibility of the presented three-phase PWM boost-buck rectifier with power-regenerating capability is demonstrated.