New Approach for Controlling PV-PV Differential Power Processing Converters

Abstract

Partial shading has serious impact on the efficiency and operation of solar PV systems resulting in significant power losses. Differential Power Processing (DPP) has been found effective in eliminating the impact of partial shading without adding extra power losses. They provide an effective alternative to distributed converters that require processing the entire extracted power scarifying the efficiency. This paper proposes a DPP structure that eliminates the needed voltage sensors for extracting the maximum power tracking. Instead of measuring the power of each individual PV submodule for tracking the maximum power, the proposed approach relies on maximizing the module current participating in eliminating the voltage measurements. Since the voltage of the module’s output is controlled by the output controller and can be considered constant to the faster inner controllers, operating the DPP converters to maximize the current should is demonstrated to maximize the power of the submodules. The effectiveness of the proposed structure is validated by simulation through Simulink under variety of shading scenarios.