A high-efficiency solar power conditioner using a zigzag-connected chopper converter

This paper proposes a new high-efficiency solar power conditioner suitable for interface with thin-film solar cells, which is composed of a zigzag-connected chopper (ZCC) converter and a series active power filter. The ZCC converter provides a bipolar rectangle voltage pulse, even where the negative terminal of the dc input is grounded without line- or high-frequency transformer. The series active power filter compensates for the harmonic voltage included in the rectangular voltage pulse produced by the ZCC converter, with a switching frequency of 20 kHz. This results in a great reduction of the switching losses and common mode voltages. Experimental results using a 1-kW single-phase converter demonstrates a high efficiency of 98%.