Implementation of a Modified PSO for MPPT Tracking in Partially Shaded PV Systems using PIC18F4550 in Proteus Software

Abstract

Partial shading conditions (PSCs) significantly degrade the efficiency of solar panels, which create numerous power peaks (local and global maximum points) on the P-V curve of the photovoltaic (PV) system due to bypass diodes in series modules. Classical maximum power point tracking (MPPT) methods often fail to distinguish the global maximum power point (GMPP) and direct the system towards getting stuck within local maxima, thereby decreasing overall power output. To tackle the partial shading issues of solar power systems, a Modified Particle Swarm Optimization (MPSO) algorithm has been developed to search for the global maximum power point (GMPP) more reliably, even when there is a complex shading pattern. The DC-DC boost converter and the resistive load are connected with the PV system while controlling the switching action with a PIC18F4550 microcontroller through applying PWM pulses based on the proposed optimization technique. To emulate and adjust the real hardware behavior at low cost, the PV modules, the Boost converter, and the MPPT algorithm were simulated and modelled using Proteus software. Experiments confirmed that the MPSO algorithm could follow the GMPP within 1.3 seconds on average, even when shading patterns changed, and it recorded an average of 99.5% efficiency. These findings indicate that the algorithm may overcome shading issues and approach maximum power levels with regularity. By combining both hardware simulation and emulation, the research confirms that this approach helps to study and develop MPPT algorithms that are applied to PV systems under partial shading conditions instead of real hardware in labs.