Fixed Frequency Model Predictive Control of a Five-level Flying Capacitor Converters with Reduced Voltage Ripple

The efficacy of a flying capacitor multilevel converter is significantly influenced by the fluctuations in the flying capacitor voltage. When these ripples become excessive, they not only amplify the voltage stress on the switching components but also compromise the integrity of the output power quality. In this study, we introduce an enhanced version of fixed-frequency model predictive control (FFMPC) tailored for a 5-level flying capacitor converter. The cost function is strategically designed to consider the output voltage, the voltage of the flying capacitor, as well as the associated ripples. Through extensive simulation testing, the proposed methodology has been validated for its ability to optimize the performance of the 5-level flying capacitor converter. The outcomes demonstrate that the FFMPC approach is highly effective in curbing the ripples in flying capacitor voltage, resulting in a marked enhancement in overall system performance. Additionally, the FFMPC facilitates accurate regulation of both the flying capacitor voltage and the output voltage, ensuring they closely adhere to the desired reference voltage levels.