SEPIC converter based transformer less grid tied PV system with reactive power compensation

This paper is aimed at the implementation of a Fuzzy Based MPPT in Transformer less grid System along with Reactive Power Compensation. A single diode model is preferred for photovoltaic array and simulation study is done by using MATLAB /SIMULINK. Voltage and current are the inputs of fuzzy logic controller and the effective value of maximum power is the output. Thus in addition to supplying voltage by the inverter without Transformer for compensate the reactive power not exceeding its power rating. This results in utilization of PV system at night and at periods of low irradiation. Rules relating the input and output of Fuzzy Logic Controller are written and simulation is performed. A dc -dc SEPIC is used for maintaining constant DC input to the inverter at various conditions of irradiation and temperature. Gating pulses to the inverter are generated by PI (Proportional integral) controller. Simulation model of a 1000W solar panel is developed and results are obtained with Fuzzy logic controller for different irradiation and temperature conditions.