Mobile QR Code QR CODE : The Korean Institute of Power Electronics
Title Improvement and Comparative Analysis of the Nonlinear Current Region in Solar Buck Battery Charger Based on Interleaved Control
Authors Byeong-Su Ko ; Il-Song Kim
DOI https://doi.org/10.6113/TKPE.2025.30.5.398
Page pp.398-405
ISSN 1229-2214
Keywords Ampere-second balance; MPPT(Maximum Power Point Tracking); SBBC(Solar Buck Battery Charger); Unified modeling
Abstract To operate at the maximum power point (MPP), the solar buck battery charger (SBBC) performs maximum power point tracking, continuously adjusting its operating point. However, because of the nonlinear characteristics of the input solar panel and the fixed voltage of the output battery, the output inductor current increases as the operating point approaches the MPP and decreases beyond it, creating a nonlinear region. As a result, conventional linear control methods, such as proportional?integral control, face constraints. In this study, the nonlinear region of the output inductor current over the entire operating range is analyzed from the perspective of ampere?second balance, and an interleaved control scheme is proposed to improve the nonlinear region. A unified modeling approach is applied to enable a precise comparison between conventional and interleaved SBBCs. The frequency responses of both systems are analyzed to validate the unified modeling. Simulation and experimental results confirm the improvement of the nonlinear region.