Abstract：FB10 three-phase non-isolated PV grid-connected inverter is investigated in this paper. Based on the theoretical analysis, a new carrier-based modulation method is proposed to suppress the common mode current. Compared with the space vector modulation method, the proposed one has unique feature of significantly simplifying the switching logic generation procedure. The system common mode voltage and current characteristics are discussed. Aside from that, a new stationary PLL-less grid-connected control solution is presented and verified. Finally, a comparison with the conventional solution is carried out, and the results demonstrate that the proposed method can achieve the constant common mode voltage, which effectively suppresses the common mode current of FB10 grid-connected inverter.
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2015, Vol. 30 
