Control of Cascaded PV-Ćuk Converter Modules by Particle Swarm Optimization under Partial Shading Conditions

This paper presents a particle swarm optimization (PSO) technique for the maximum power point tracking of a PV power generation system under unequal solar irradiation. The system consists of multiple PV-Ćuk converter (PVCC) modules in a series chain and a terminal step-up converter for load connection. The bidirectional Ćuk converter in each PVCC has two PV panels connected at its four terminals. The configuration offers the advantage that under shading or module mismatching, the Ćuk converter provides a current bypass which can allow two PV panels track their available maximum power. The new PSO-based MPPT control scheme estimates the voltages corresponding to the maximum power each PV panel can generate under its specific weather conditions. Tuning of the controller parameters is based on the transfer function model of the proposed PVCC. The results show that the proposed PSO MPPT and modelbased control can ensure high performance maximum power generation regardless of shading conditions.