Three-Phase Multilevel Current Source Rectifier With Double DC Output Using Semi-Controlled Converters

This paper presents a novel multilevel current source rectifier (MCSR) with dual DC outputs and a reduced number of active switches. The number of switches is reduced by replacing them with diodes. The aim of this modification is to improve the efficiency of the converter and reduce its cost. However, the diode conditions limit its functionality to rectification only, which provides unity power factor. The proposed converter can generate equivalent input current levels while uses fewer components than the conventional multilevel current source converter. The study evaluates and compares the proposed converter with the conventional topology in terms of number of components, semiconductor losses, harmonic distortion, and cost distribution. A modulation method using space vector modulation is formulated to achieve DC-link balanced currents for the proposed converter. In addition, a field-programmable gate array (FPGA)-based controller is proposed to implement the modulation strategy and control the converter operation in conjunction with a digital signal processor (DSP). Simulation and experimental results for a 1 kW prototype confirm the feasibility and performance of the proposed topology.