Floating gate power supply of multilevel converters for circuit integration

There is the possibility of the intrinsic elimination of harmonics and electromagnetic interference (EMI) by introducing multilevel converters with a large number of levels. As the number of levels increases, the number of the main switching devices on their higher side increases, and their floating gate power supplies become larger scale circuits. Because it is necessary to integrate the floating gate power supplies from the practical viewpoint, it is one of the important issues to realize the floating gate power supplies, which consist of the components suitable for the integration. In this paper, bootstrap circuits, charge pump circuits, and self power supply circuits, already proposed for the conventional 2-level converters, are extended to the floating gate power supplies for the multilevel converters: diode-clamped converters, flying capacitor converters, and series-connected H-bridge converters. The theoretical and experimental investigations of the floating gate power supplies for the multilevel converters considering the main circuit topology and the main circuit control are shown. From these results, the applicability and the required modification of the floating gate power supply methods are clarified.