Timing Control of a Modular Multilevel Converter Using a Bootstrapping Circuit as Submodule Switch Driver

Abstract

Subject of this paper is the implementation of a bootstrap driver for the GaN-based transistors inside the submodules of a modular multilevel converter (M2C). To compensate the disadvantage of a limited on-time of the high-side transistor in the half-bridge configuration, a timing control function is added to the sorting algorithm of each arm of the converter. This function switches two submodules if a maximum on-time of one submodule is reached. The proposed control was simulated using a discrete model.