Three-phase four-switch partial resonant soft switched rectifier

The paper investigates a soft-switching partial-resonant link AC/DC converter. The proposed converter uses 4 active switches and overcomes the various shortcomings of conventional resonant AC Link schemes such as the need for a four-quadrant ac switch. The switching operations occur at zero voltage instants thus lowering the losses. The input current is harmonic free. It can perform buck and boost operations. As the converter requires less number of active switches and operates at high switching frequency, it offers both improved performance and considerable reduction of volume, weight and cost. A prototype converter system has been built and tested. The loss data from a prior characterization study has been used to compare the efficiency of the converter for different combinations of devices. It has been shown that the combination of SiC-MOSFET and Si-PiN Diode would lead to a better more efficient converter. The converter has also been compared with the state of the art available solutions. The various advantages in terms of switch reduction and eventual reduction of switching and conduction losses have been tabulated. The topology is expected to offer compact, fast, efficient and inexpensive solution to the present AC/DC power conversion requirements.