Relationship between flying capacitor multilevel inverter PWM methods and switching loss minimized PWM method for flying capacitor multilevel inverter

The relationship between the carrier-shifted PWM and the space vector PWM in flying capacitor multilevel inverters is established, and according to the relationship, the switching loss minimized PWM for flying capacitor multilevel inverter is presented. In comparison with conventional carrier-shifted PWM method, each phase of the flying capacitor multilevel inverter can have the 120/spl deg/ no switching zone in one period by the proposed method; according to power factor angle, 120/spl deg/ 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 tightness and practicability are verified by the simulation and experimental results.

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