Modeling and Current-Mode Control of a DCDC Modular Multilevel Converter

This article presents a dynamic model and a current-mode control for a dc-dc modular multilevel converter with the ultimate aim of expanding the converter to a three-leg configuration to reduce the filtering requirements of the dc ports. A complete model of the converter including a systematic approach for the control of the power throughput is developed. It is then shown that the expansion from a single-leg to three-leg configuration requires no additional modeling, and that the three-leg converter significantly alleviates the filtering requirements on both the high-voltage and low-voltage sides. The proposed model and control technique are verified using simulation results based on the MATLAB / Simulink software environment for both the single and three-leg configuration. Further verification is carried out through a single-leg 1-kW experimental prototype.

Automated summary

This article introduces a dynamic model and current-mode control for a DC-DC modular multilevel converter, aiming to expand the converter to a three-leg configuration in order to reduce filtering requirements. The complete model of the converter and systematic approach for power throughput control are developed and verified through simulations and experiments. Expanding from a single-leg to three-leg configuration effectively alleviates the filtering requirements on both high-voltage and low-voltage sides.