Research on Switching Loss Minimized PWM Method for Flying Capacitor Three-Level Inverters

摘要

The switching loss minimized PWM method for flying capacitor three-level inverter is presented based on the study of PSPWM and SVPWM for flying capacitor multilevel inverter in the paper. In comparison with conventional carrier-shifted PWM method, each phase of the flying capacitor multilevel inverter can have the 120° no switching zone in one period by the proposed method; according to power factor angle, 120° no switching zone can be adjusted to be farthest located in the centre of the peak value region of the load current, hence, the switching loss can be greatly reduced and the efficiency of the system can be greatly improved. The simulation and experimental results show that switching loss of 33 percent is reduced. The switching loss minimized PWM in flying capacitor three level inverter is presented.