Diode-clamped multilevel converters with integrable gate-driver power-supply circuits

Recent contributions in pulse width modulations (PWM) for multilevel diode-clamped converters enable the use of these converters with passive front-ends, any number of levels, and small DC-link capacitors. Highly compact converters designs based on these topologies can be envisioned. However, the design of the gate-driver power-supply for the multiple controlled semiconductor devices remains an important issue to be addressed. This paper focuses on the design of such circuits and the analysis of the resulting multilevel converter performance. A simple circuit connected across each power switch and monolithically integrable within it is selected. These circuits lead to simple, compact, and efficient converter designs. The main issues arising from the operation of the multilevel converter with such circuits are analyzed, and both hardware and software solutions are proposed. In particular, a new PWM strategy is presented. Experimental results are provided verifying the good performance of all proposed solutions.