A low supply voltage mixed-signal maximum power point tracking controller for photovoltaic power system

This paper presents a mixed-signal maximum power point tracking (MPPT) integrated circuit (IC) controller implemented with a mixed-signal multiplier for photovoltaic (PV) systems. The mixed-signal MPPT IC controller which is easily implemented on a low cost single chip IC, is based on perturbation and observation method. The mixed-signal multiplier combines features of analog control with digital control. Compared with digital MPPT controllers, up to 10-bit high resolution analog to digital converters are significantly reduced to simplify the hardware complexity of IC realization. Compared with analog MPPT controllers, which have a narrow linearity range of low supply voltage, the proposed controller has high linearity of low supply voltage and precise calculations for MPPT to extend the input voltage control range of the PV power system. Simulation results confirm the high linearity of the mixed-signal multiplier and the function of MPPT for a 200 W PV system.