Development of a residential use, utility interactive PV inverter with isolation transformer-less circuit-development aspects

A 3 kW residential use, utility interactive PV inverter with an isolation transformer-less circuit has been developed. Aiming at a cost effective, compact and highly efficient PV inverter, a prototype inverter was fabricated and tested. In order to improve efficiency, AC reactors and other components were specially designed and evaluated. A conversion efficiency of 94.5% was attained. The cost of the inverter is aimed at Y50/Watt on the basis of 3000 units/month production.