Effect of Bypass Diode on Power Generation of Three-Dimensional Curved Si Photovoltaic Module

Three-dimensional (3-D) curved photovoltaic (PV) modules are a potential power source for vehicles with curved surfaces. However, the irradiance on a 3-D curved PV module is nonuniform compared to a conventional flat PV module, which leads to a current mismatch and reduced power generation performance. The conventional PV modules have bypass diodes (BPD) to mitigate power degradation due to partial shadows. To address nonuniformity specific to 3-D curved PV modules, we investigated the BPD configuration. The effectiveness of the BPD configuration was simulated via optical analysis and circuit analysis with meteorological data (at Tokyo and Phoenix). For 3-D curved PV modules with a radius of curvature in the range of 1–3 m, the effectiveness of BPD becomes more pronounced when the curvature radius and diffuse fraction are smaller. In addition, among the BPD configurations examined in this simulation, remarkable power improvement was obtained when 50% of the total number of solar cells in the module was coupled with BPD. The simulation method was validated via an outdoor experiment using a prototype 3-D curved surface module.