A Charge Redistribution Ladder Architecture for Voltage Equalization and Enhanced Performance of Partially Shaded PV Arrays

Photovoltaic (PV) arrays are highly vulnerable to partial shading, leading to mismatches and voltage imbalances among modules, resulting in power loss and distortion of performance characteristics. This paper proposes a step-wise charge-redistribution voltage balancing approach to minimize module mismatch. The approach utilizes a modified ladder-based switched capacitor mechanism applied to modules for efficient charge redistribution and voltage balancing. The methodology is tested on a 9x9 PV array under static and time-domain-based moving shading conditions and compared with various existing reconfiguration, power optimizer, and hybrid techniques. The investigation is conducted in MATLAB and further validated on the OPAL-RT 4510 hardware-in-the-loop FPGA-based real-time platform, ensuring high fidelity and practical applicability. The analysis reveals that the proposed approach effectively minimizes voltage differences among modules, eliminates characteristic distortion, and enhances the array power by 29.27%, 14.97%, 4.90%, 4.41%, and 5.63% than conventional, static, and dynamic reconfigurations, power optimizers, and hybrid techniques, respectively achieving an overall power conversion ratio of 99%.