A novel stand-alone PV generation system based on variable step size INC MPPT and SVPWM control

Abstract

The power available at the output of photovoltaic (PV) cells keeps changing with solar irradiation and ambient temperature because PV cells exhibit a nonlinear current-voltage characteristic. So its maximum power point of photovoltaic cells varies with solar irradiation and ambient temperature. Maximum power point tracking (MPPT) techniques are used in PV systems to make full utilization of PV array output power which depends on solar irradiation and ambient temperature. Compared with the conventional fixed step size the incremental conductance (INC) method, this paper proposes a variable step size INC MPPT algorithm which can effectively improve the MPPT speed and accuracy simultaneously. Inverter control is another key aspect in PV generation system. This paper proposes Space Vector Pulse Width Modulation (SVPWM) control scheme for three-phase PWM inverter is used in PV generation system. A novel stand-alone PV generation system based on a variable step size INC MPPT method and SVPWM control scheme for three-phase voltage source PWM inverter is built in Matlab/Simulink software in this paper. Results of simulation show that the novel stand-alone PV generation system can have good performance of MPPT and the high quality of output voltage.