Pulsewidth-Modulated Dual-Half-Controlled Converter

The dual-half-controlled-converter (DHCC) is a voltage-source active rectifier which can be considered as a potential alternative to the conventional three-phase six-switch boost rectifier. The DHCC is attractive due to its lower component current rating, immunity to shoot-through, simpler gate drive circuitry, lower semiconductor losses, and fault redundancy. Compared to a six-switch voltage-source-converter and a diode rectifier with a shunt active filter, DHCC presents some advantages and has good potentials for grid-tied and generator-tied applications. In the previous literature, the DHCC was controlled through a hysteresis regulator. This paper discusses in detail the current compensation and harmonic cancellation methodologies and presents improved control techniques for the three-phase three-wire DHCC using interleaved pulsewidth modulation (PWM). Compared with the existing hysteresis controller, the proposed fixed-frequency PWM controllers require smaller filtering elements and/or a lower sampling frequency. Both simulation and experimental results are presented to demonstrate the superiority of the proposed PWM control algorithm. The impacts of input reactor sizing and dc-link voltage rating are analyzed and discussed.