Non-isolated high gain boost converter for photovoltaic applications

摘要

The output voltage from renewable energy sources like photovoltaic cell or array will be at low level. Thismust be stepped up by an order of around 20 for practical applications or grid connection. Series connection of arrays is not a viable solution. Hence, high gain DC-DC converters are essential. The proposed DC-DC converter topology is a multilevel boost converterwhich combines the simple boost converter and switched capacitor function to provide high voltage gain. The proposed topology uses only one switch, one inductor, (2N-1) diodes and (2N-1) capacitors for obtaining an output which is N times the conventional boost converter. In this topology, each device blocks only one voltage level. Hence, low voltage devices may be used. The main advantages of this topology are continuous input current, large conversion ratio without extreme duty cycle or transformer, which allows for high switching frequency. This circuit can be built in a modular way. The proposed converter is simulated and the output waveforms are plotted. The experimental setup will be taken up as future work. Further, it is proposed to be used in conjunction with multilevel inverters to facilitate grid connection.