Analysis and design of modular soft switching SEPIC DC-DC converter for phovoltaic applications

In this thesis, a modular DC-DC converter that allows the photovoltaic module to operate at maximum power point is developed. In the converter, a quasi-resonant zero voltage switching SEPIC converter is selected in order to get high efficiency and small size. The zero voltage switching region of the converter is examined in detail. A prototype of the proposed SEPIC converter for 80W silicon photovoltaic module is realized, and experimentally tested on the system, which comprises two photovoltaic modules connected in series. It is measured that the proposed converter increases the output power 7% as compared to the conventional method under non-uniform irradiation condition. As a result, for the systems operating under non-uniform irradiation conditions frequently, the proposed modular SEPIC DC-DC converter can increase the efficiency considerably with respect to the conventional method.