抄録
A single-phase voltage-doubler rectifier, which has two auxiliary bidirectional switches, is studied. The proposed rectifier has the advantages that the imbalance of the voltages across the capacitors, connected in series, is minimized independent of the working conditions and the discharge of capacitors is adjusted by arranging two auxiliary bidirectional switches. Therefore, the total capacitance of the rectifier can be reduced. The tested setup, using four insulated-gate bipolar transistors (IGBTs) and a microcomputer as a PI control-ler, is implemented and IGBTs are switched with 20kHz, which is out of audible band. Moreover, a rigorous state-space analysis is introduced to predict the operation of the rectifier. From the results, the well-balanced capacitor voltages can be achieved and the input current can be sinusoidally waveshaped with a near-unity power factor under the steady state and transient conditions even if the rectifier is operated with small series-connected capacitors. Consequently, the single-phase voltage-doubler rectifier studied is suitable for AC-DC conversion equipment with output voltage higher than twice that of the supply and with reduced total capacitance.
