Control Method for Universal Smart Power Module Considering Wireless Communication

Abstract

A universal smart power module (USPM) has been studied as a modularization method for rapidly developing power converters with various specifications. Herein, a control method is proposed for a three-phase modular multilevel converter composed of USPMs. The autonomous balance control of the proposed control method suppresses the variation in the voltage of the cell capacitor and the disturbance caused by communication delays. This enables the application of the proposed versatile extension method. Moreover, current droop control suppresses the effects of delay variations caused by wireless communication and eliminates system instability caused by control interference between modules. Based on the experimental results of steady-state and load-fluctuation responses with a simulated wireless communication implementation, the deviation from the command values of the line and cell capacitor voltage is less than 5%. Furthermore, the autonomous balance control improved the variation in the capacitor voltage in all modules from 9.70V to 1.94V. The results validate the effectiveness of the proposed control method in wireless communication environments.