Patent ID: 8934269
Filing Date: 2015-01-13
Classification: H02J,H02M,Y02B,Y02E

Abstract:
1. A photovoltaic power conditioning unit for delivering power from a dc power source to an ac mains power supply output, the photovoltaic power conditioning unit comprising: a dc power input to receive dc power from a photovoltaic power source; an ac power output for delivering ac power to said ac mains power supply; a dc link coupled between said dc power input and said ac power output; a dc-to-ac converter coupled between said dc link and said ac power output; first and second dc-to-dc power converters, each dc-to-dc power converter coupled between said dc power input and said dc link and each dc-to-dc power converter having a series inductor in a connection between said dc-to-dc power converter and said dc link, wherein each dc-to-dc power converter comprises a transformer having an input winding and an output winding, wherein said output winding of said transformer has a winding tap between first and second portions of said output winding, wherein said series inductor comprises an inductor connected to said winding tap, wherein the series inductor is shared by first and second rectifiers for connecting to the first and second portions of said output winding; and a dc conversion stage controller, coupled to sense an input or output power of said power conditioning unit and to control said first and second dc-to-dc converters; and wherein said dc conversion stage controller is configured to control, responsive to said sensed power, whether one or both of said dc-to-dc converters operates to feed dc power from said dc input to said dc link.