Analysis and PWM control of three-phase boost-derived hybrid converter

This paper proposes a power converter architecture which can provide a step-up dc and a three-phase ac output simultaneously from a single dc input in a single-stage conversion. This architecture, named three-phase boost-derived hybrid converter (3-φ BDHC), is derived from a conventional boost converter by replacing the control switch with a three-phase bridge network. Compared to conventional voltage source inverters, the 3-φ BDHC topology has inherent shoot-through protection capability and continuous input current. Since the boost and the inverter functions are integrated within a single architecture, the power processing density of the overall system is higher and the coordination of power flow into two different outputs becomes easier. Both the step-up dc and the three-phase ac outputs can be independently regulated. In addition to a conventional 3-φ BDHC, this paper also describes the 3-φ BDHC topology where the neutral of the three-phase filter is connected to the split-dc output capacitor. This split-dc capacitor arrangement allows for independent control of each of the three-phase voltages at unbalanced load conditions. A suitable pulse-width-modulation (PWM) control strategy for the purpose of regulation of each of the outputs (dc and ac) has been described. Experimental results have been shown to validate the converter operation, when a single dc input provides a step-up dc and a three-phase ac using a 150 W experimental prototype; the ac output is generated at fundamental frequencies of 50 Hz and 400 Hz.