A comparative analysis of Maximum Power Point Tracking (MPPT) Techniques of a Solar Panel

Abstract

A photovoltaic panel operates along a non-linear Power-Voltage (P-V) curve. When a load is directly connected to the photovoltaic (PV) panel, the output voltage of the panel changes with the delivered current. The panel’s P-V characteristic shows that the power it delivers is maximum at one particular operating combination of voltage and current, called the Maximum Power point (MPP). However, this MPP is not static and it shifts with varying loads as well as due to changes in temperature, solar irradiance level. This paper compares the performance of three MPPT techniques namely, Perturb and Observe (P&O), Sliding Mode Control (SMC) and Fractional Short-Circuit Current (FSCC) of a given PV system through simulation. The PV system is modeled in MATLAB/Simulink environment and it consists of a 20 W PV module supplying power to a resistive load through a DC-DC Boost converter. Algorithms of the three aforementioned MPPT control techniques (PO, FSCC, and SMC) are developed and simulated under changing solar irradiance level and their performances are compared. It was observed that Sliding Mode Control technique has the fastest tracking time and produced the least oscillations at steady state.