Two-phase X-type current source rectifier with reduced active switch count for open-end permanent-magnet synchronous generator

In this paper two two-phase current source open-end asymmetric rectifiers are proposed. These new rectifiers are derived from an improved multi-phase crossed switches current source converter, named X-type CSC. The X-type CSC presents independent full quadrant operation, lower DC-bus current value, high magnetic power density, higher efficiency (when compared to similar ones), and high AC output voltage waveform quality. Being used exclusively as a rectifier, the X-type CSC can be even further improved. One can replace the series switch-diode configurations by only diodes, resulting in an asymmetric converter with only four active switches. With this modification, the efficiency can be increased and the cost reduced. The two-phase asymmetric X-type current source rectifiers are presented with their respective pulse-width modulation technique and also proper control technique. Simulation and experimental results are presented in order to validate the theoretical approach. At last, a comparison of the studied topologies is made and the best converter is selected.