Space Vector Modulation Control of a Seven-Level Hybrid Converter

In this paper a novel seven-level hybrid converter topology is introduced which is based on the active neutral-point-clamped multilevel converter concept and is suitable for high-power applications. The paper also proposes a Space Vector Modulation (SVM)-based switching strategy that takes advantage of redundant switching vectors of the SVM method to counteract the voltage drift phenomenon of the proposed converter topology. The limit to the range of operation of the seven-level converter based on the proposed SVM strategy is also presented. It is shown that the ability to stabilize the DC-link capacitor voltages and the floating capacitors is a function of the converter operating indices, i.e. the load power factor and modulation index. Performance of a converter under various operating conditions, based on time-domain simulation studies in the MATLAB/SIMULINK environment, is evaluated.