Control of the Maximum Power Point of a Solar Panel, Using Servo System Controller With Integrator and Pi Controller Designed by the Roots Locus Method

Abstract

Photovoltaic system applications require to use a solar panel, a power converter, and a load. When voltage reduction from a panel to a battery is necessary, a buck converter is usually proposed. In the specialized literature, there are a wide variety of controllers oriented to commercial panels; However, even though measuring the energy extraction of a solar panel is the main indicator, there are other metrics such as switching effort that also affect the overall performance of the PV system. The main contribution of this work is the design of two digital controllers for photovoltaic energy extraction: a servo system controller with integrator and a PI controller based on root locus techniques considering an MPPT algorithm and system perturbations to demonstrate the reliability and efficiency of the controllers under different system scenarios. Finally, a detailed explanation of the performance of the controllers is given, showing that the two algorithms are suitable for controlling the point of maximum power in photovoltaic panels.