Analysis and Optimization of Flexible MCPT Strategy in Submodule PV Application

Distributed maximum power point tracking (DMPPT) can effectively increase the power generation ability of photovoltaic (PV) systems in mismatch conditions. To further recover mismatch power loss inside PV panels, submodule realization is developed as an improved penetration of DMPPT concept. This paper proposes an optimized submodule level DMPPT system with a flexible time-sharing maximum current point tracking algorithm which detects the output current of series-connected dc-dc converters. Comparing with current PV optimizer and other submodule DMPPT solutions, the proposal can always guarantee that each PV submodule outputs individual true maximum power regardless of irradiance cases while eliminating the need for several MPPT units and current sensors in the system. Enormous potential of single control IC can be fully developed with fewer components (voltage sensors, current sensors, and relevant AD/DA units) for further integration in PV application.