Implementation of dithering digital ripple correlation control for PV maximum power point tracking

This work demonstrates a method for rapid maximum power point tracking in photovoltaic applications using dithered PWM control. Constraints imposed by power consumption, cost and component size, limit the available PWM resolution of a power converter, and may in turn limit the MPP tracking efficiency of the PV system. PWM dithering can be used to improve average PWM resolution. However, additional tracking delays are also introduced. By applying digital dithering ripple correlation control to the ripple caused by PWM dithering it is possible to achieve high tracking speed in addition to high PWM resolution. We present a theoretical derivation of the principles behind DDRCC, as well as experimental results that show excellent tracking speed and accuracy with basic hardware requirements.