Abstract：This paper describes a seven-level hybrid cascaded inverters, which can be applied to single phase PV grid-connected system. The operating mode for the circuit and the way that dead-time and switching action affect the inverter, are analyzed. A mode based on the optimum way is given to control full-bridge support capacitor voltage, and the implementation condition of the mode is calculated. Using single carrier SPWM mode which occupy less digital signal processor (DSP) system resources to achieve the modulation. To verify the feasibility of the system, a simulation model and a low power inverter was constructed and results are provided.
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2015, Vol. 30 
