Novel High Gain, High Efficiency DC-DC Converter Suitable for Solar PV Module Integration With Three-Phase Grid Tied Inverters

This paper proposes a novel configuration for high gain, high efficiency dc-dc converter comprising a single switch, two intermediate capacitors, and a coupled inductor for low voltage solar PV module fed applications. The high voltage gain is achieved by charging the intermediate capacitors through the coupled inductor in parallel and discharging in series. In a two winding coupled inductor, considered in the presented work, maximum two intermediate capacitors can be integrated with the secondary winding. A passive lossless clamped circuit is also provided in the converter, which recovers the leakage energy to improve the efficiency and alleviate large voltage spike. The structure of the circuit is such that the power device voltage stress is reduced thereby increasing the efficiency. The maximum power point tracking at various irradiation levels is implemented in the proposed converter. Laboratory prototype of a 300-W system with 30-45-V input and 700-V output was built to validate the theoretical claims. All the detailed analysis, simulation, and experimental waveforms are presented. A maximum converter efficiency of around 95% is achieved.