Modified Control Strategy of Stacked Multicell Converter with Model Predictive Control

Owing to its symmetric and extendable circuit characteristics, the stacked multicell converter (SMC) can be configured to provide flexible voltage levels. Traditionally, achieving higher voltage levels of SMC requires extra stacked subcells resulting in extra device costs as well as power losses. To address this, modified capacitor voltage ratios of SMC for the improvement of output voltage resolution are proposed and studied in this paper. The motivation behind is to increase the switching voltage level of SMC meanwhile limiting the numbers of semiconductor devices and flying capacitors (FC5). By applying a model predictive control (MPC) algorithm with reduced computational burden, a SMC constructed with three stacked subcells is investigated under the seven/nine/eleven-level operation modes.

Automated summary

The paper proposes a method for improving the output voltage resolution of the stacked multicell converter (SMC) by modifying the capacitor voltage ratios to increase the switching voltage level. Through the study, it is found that with reduced computational burden, the performance of a SMC constructed with three stacked subcells can be explored under different operation modes.