A current sensorless MPPT algorithm for a low-cost PV array controller

In this paper, a current sensorless maximum power point tracking (MPPT) algorithm for a low-cost PV array controller is proposed. In order to reduce the cost on controllers and sensors, the PV array controller is based on controlling turn-on time of the interleaved flyback converter and DC bus output is designed. The controller only samples the input voltage without the need for a current sensor, which cuts down the cost of the system. The interleaved flyback converter is used to reduce the filtering pressure of the input and output capacitor of the converter. What's more, the converter is designed to work in quasi-resonant and soft-switching state to improve efficiency. To verify the effect of proposed MPPT algorithm, a design example of a 50kHz, 32V, 4A input, 225V output 128W flyback converter is given in this paper.