Output voltage sensor based maximum power point tracking for PV system using SEPIC

Maximum power point tracking (MPPT) algorithm with a single output voltage sensor for a photovoltaic (PV) system is presented in this paper. The MPPT algorithm is developed by considering the slope (dV₀/dD) of V₀ - D characteristics. In this method only a voltage divider circuit is used to sense the converter output voltage (V₀). The steady state behavior, tracking performance for a change in insolation and for a load variation with the output voltage sensor based MPPT algorithm are addressed through experimental results to determine the tracking efficiency. The duty cycle (D) is generated directly without any proportional-integral control loop to simplify the control circuit. Single ended primary inductance converter (SEPIC) is used for experimental validation of the algorithm with microcontroller.