Photovoltaic module common sense and common appearance defects

Crystalline silicon photovoltaic modules are an important part of the entire photovoltaic system. The quality of the module affects the power generation efficiency of the power station. The module is composed of EVA, battery cells, backplanes, smooth glass, welding strips, frames, junction boxes, sealants, etc. The various materials of the module and their common appearance defects are as follows.
EVA is used to encapsulate the spliced ​​battery strings. It is a copolymer of ethylene and vinyl acetate. It is non-sticky at room temperature. After hot pressing under certain process conditions, it melts and solidifies, becoming completely transparent. The cured EVA is elastic and can withstand atmospheric changes. Moreover, it can increase the light transmittance of the glass after bonding with the glass, which has a gain effect on the output of the photovoltaic module. Common problems are caused by materials and processes.
The battery cell is mainly made of semiconductor crystalline silicon. After being exposed to light, the P-N junction of the battery will form an electric potential difference when exposed to light, thereby generating current. The general thickness is 180~220μm, and it is easy to be damaged by force during the production process.
There are many structures of backplanes. Currently, TPT, TPE, TPF, KPK, KPF, etc. are mainly used. They are used as packaging materials on the back of the assembly to reflect sunlight, have high infrared emissivity, reduce the temperature of the assembly, and are conducive to improving the efficiency of the assembly. They also have the characteristics of resistance to water vapor penetration, corrosion resistance, and insulation. Common problems are divided into backplane process, material, and external force.
The welding strip is a tin-coated copper strip with interconnection strips and bus strips. The interconnection strips connect the cells, and the bus strips connect the battery strings. They have the function of conducting electricity. Common problems are welding strip materials, welding, etc.
The glass of photovoltaic modules generally uses low-iron tempered velvet glass or coating, which can protect the cells, waterproof, high light transmittance, reliable wind pressure resistance, hail impact resistance, etc. Common problems are caused by glass materials or external forces.
The junction box consists of a box cover, a box body, a pole tube, a connecting wire, and a connector. The sealing methods usually include potting glue sealing and sealing ring sealing, so as to connect the assembly lead wires, export current, protect heat dissipation, prevent hot spot effects, and resist aging.
The frame is made of aluminum profile and the surface is anodized, which has insulation and corrosion resistance properties. It protects components and increases load-bearing capacity, making it easy to transport and install. Common problems are caused by materials and external forces.