| Abstract [eng] |
This master thesis investigates the impact of PV modules with bypass (shunt) diodes and power optimizers under different shading conditions on generation and other electrical parameters. The theoretical part of the study provides an overview of the architecture and the principle of operation of PV modules and power optimizers. The most popular manufacturers of power optimizers and their products are described. Based on scientific papers, cases of shading conditions for modules without bypass diodes, with bypass diodes and with power optimizers are described. The changes of module parameters under shading on PV modules are mathematically described, as well as the mathematical model of power optimizers and bypass diodes. The theoretical PV and IV curves for shadow incidence on PV modules without bypass diodes, with bypass diodes and with power optimizers are analyzed. The simulation part of the study was carried out using PVSOL Premium 2024 software package. The model was developed for 10 different shadowing cases. The simulation resulted in PV and IV characteristics of PV modules with bypass diodes and power optimizers. The DC generation of fixed shading was compared. A realistic case of variable shading has also been simulated and the DC power generation has been compared in daily and full year sections to assess the loss of generated electricity due to the negative influence of shading. In the investigative part, a study on a real solar power plant of 29,7 kW was also carried out. The variation of the electrical parameters of the PV modules under different shading cases was investigated. Variants with and without power optimizers were investigated in order to study the performance of bypass diodes. The generated DC power under different shading cases was also calculated and compared. During the study it was observed that the bypass diodes in the PV module do not work in the presence of narrow shadows (up to 1 cm wide), so additional tests were carried out to investigate the performance of the bypass diodes and the power optimizers in the presence of narrow shadows falling on the PV modules. |
