ABSTRACT
The diode-clamped multilevel converter (DCMC) has a common DC bus, and thus it is inherently suitable for B2B connection. This chapter describes a complete control scheme for a back-to-back DCMC converter in a motor drive application. The particular control objectives of the grid converter and the load converter, as well as their solutions, are analyzed and developed. In order to introduce the variant of model predictive direct torque control (MP-DTC) for multilevel converters, a brief review of the classic DTC for two-level inverters is given in the following paragraphs. The line converter is connected to the grid through the coupling reactor LC , while the load converter drives the IM directly. A medium-voltage motor drive that uses two five-level DCMCs has been analyzed in which the predictive balancing scheme was extended to control the external variables on both converter sides: the instantaneous power on the grid converter and torque/flux control on the load converter.
