Single-phase switching-mode rectifier with capacitor-clamped topology

A single-phase switching-mode rectifier with capacitor-clamped topology is presented to achieve power factor correction, eliminate current harmonic, draw a sinusoidal line current from the AC source and maintain the DC-link voltage constant. The proposed switching-mode rectifier has the capability of bidirectional power flow. Six active switches and one clamping capacitor are used in the rectifier to achieve the three-level pulse-width-modulated operation. A carrier-based current controller is adopted in the inner loop to track the reference line current. To regulate the DC bus voltage constant, a voltage controller based on a proportional–integral scheme is used in the outer loop. A voltage self-balancing technique is adopted in the control scheme to balance the capacitor voltages. Based on the proposed control scheme, a three-level pulse-width-modulated waveform is generated on the AC terminal of the rectifier. The proposed control algorithm illustrates its validity and effectiveness through computer simulation and experimental results.