Modeling and simulation of photovoltaic system with soft switching SEPIC converter

Solar energy is the most promising source of renewable energy. Intensive research is carried out in all the areas associated with solar energy. In this paper a soft switching SEPIC converter is proposed for the inverter section of the PV system, this is aimed at reducing the switching losses in the converter section and hence the efficiency of the system increases. SEPIC converters used by the researchers have noninverted output but medium efficiency. A Soft Switching SEPIC converter has a non inverted output and a efficiency of about 94%. The converter uses two switches, and ZVS of both the switches are achieved by using a coupled inductor and a auxiliary inductor, and ZCS of the output diode is achieved by resonance in the voltage multiplier circuit. An Incremental conductance MPPT algorithm is used to control the converter. Simulation study has been done in MATLAB V3.2. Analysis proves that Soft Switching SEPIC converter has an efficiency of a 94%, an increase of 40% has been found out with respect to existing system. This increase is likely to contribute to overall system efficiency.