Switching frequency optimized granular maximum power point tracking for PV systems

Granularity in tracking the maximum power point of photovoltaic modules improves the amount of harvested energy at the expense of extra added power electronic devices. For a convincing outcome, the efficiency of both the maximum power point tracking algorithm and the power electronic devices should be maximized. The switching frequency of the pulse width modulation controlled converters determines the efficiency and mode of operation of these converters. In this paper, an irradiance-based frequency hopping scheme is proposed to improve the efficiency and to control the mode of operation of the module integrated converters. The scheme is implemented in the distributed maximum power point trackers of photovoltaic modules to facilitate flexible operation and simple control aiming at an efficient microgrid. The paper utilizes a certain topology and configuration for module integrated converters that ensures both efficiency and smart integration of photovoltaic systems into microgrids.