A Generalized Phase-Shift PWM Extension for Improved Natural and Active Balancing of Flying Capacitor Multilevel Inverters

The emergence of wide bandgap power devices has brought the attention back to flying capacitor (FC) multilevel inverters with a large number stages, in an effort increase density by minimizing passive components. main challenge that such systems face, particularly ones based on high-frequency Gallium-Nitride and small-value ceramic capacitors, relate stringent requirements for precise fast balancing. Conventional natural balancing techniques exhibit poor settling times, while most improved natural balancing methods are not easily scalable more than five levels. alternative xmlns:xlink="http://www.w3.org/1999/xlink">active normally requires one isolated sensor per FC which increases overall system cost footprint, or single ac-side is compact but calls sophisticated PWMs again available multiple In this paper we introduce generalized pulse width modulation (PWM) strategy phase-shift carrier swapping principles arbitrary We provide easy intuitive method extraction PWM pattern, switching states, their sequence. Simulations were carried out Matlab/Simulink experimental tests conducted single-phase 7-level GaN inverter prototype. Not only extended advantageous balancing, it also provides right zero states sensing active