PWM Boost Converter Integrating Differential Power Processing Converter to Enhance Energy Yield of Photovoltaic Panels Under Characteristic Mismatch Conditions

Abstract

Partial shading on a photovoltaic (PV) panel consisting of multiple substrings is known to trigger a significant reduction in energy yield and the occurrence of multiple maximum power points (MPPs), including one global and multiple local MPPs. Uneven irradiance on curved PV panels, such as flexible panels and solar roofs of electric vehicles, also causes characteristic mismatch, triggering the same issues. Although various types of differential power processing (DPP) converters have been proposed to preclude the characteristic mismatch issues, the DPP converter is separately required in addition to an existing boost converter for panel control, resulting in increased system complexity, cost, and volume. This study proposes a novel integrated converter that realizes system simplification and circuit miniaturization by integrating a PWM boost and a DPP converter into a single unit. Laboratory and field tests were performed emulating partial shading and characteristic mismatch conditions. The proposed converter eliminated local MPPs and increased maximum power while boosting the panel voltage, demonstrating the efficacy of the proposed integrated converter.