High-efficiency inverter with H6-type configuration for photovoltaic non-isolated ac module applications

A novel, high-efficiency inverter using MOSFETs for all active switches is presented for photovoltaic, non-isolated, ac module applications. The proposed H6-type configuration features high efficiency over a wide load range, low ground leakage current, no need for split capacitors, and low output ac-current distortion. The detailed power stage operating principles, PWM scheme, and novel bootstrap power supply for the proposed inverter are described. Experimental results of a 300 W hardware prototype show that not only are MOSFET body diode reverse-recovery and ground leakage current issues alleviated in the proposed inverter, but also that 98.3% maximum efficiency and 98.1% European Union efficiency are achieved.