Portable EL Detector: A Crucial Tool for Photovoltaic Module Quality Assurance

Photovoltaic (PV) power generation, as a clean energy technology, relies on the stability and durability of its components to ensure long-term power generation efficiency. However, with the advancement of PV module manufacturing technology and the aim to reduce costs, modules are becoming thinner, which to some extent reduces the mechanical strength of the cells. This makes them more susceptible to micro-cracks during transportation and installation. Additionally, PV power stations with flexible mounting systems may accumulate large areas of micro-cracks due to the flexible characteristics of the mounting system when encountering extreme weather conditions like typhoons. These micro-cracks not only affect power generation efficiency but can also pose safety hazards.

Therefore, the detection and prevention of micro-cracks have become an essential part of the operation and maintenance (O&M) and acquisition processes of PV power stations. Micro-crack detection is usually carried out before and after lamination using Electroluminescence (EL) testing, which can identify micro-crack issues at an early stage of the module, thus avoiding quality risks.

The working principle of EL (Electroluminescence) testing is based on the electroluminescence effect of semiconductor PN junctions. In a photovoltaic cell, when a forward bias is applied, the built-in electric field of the PN junction is weakened, leading to the injection and recombination of electrons and holes, thereby producing photons. The emission of these photons can be captured by an infrared camera and converted into images, visually displaying the internal condition of the cell.

A Portable EL Detector is a device specifically designed to detect internal defects in photovoltaic cell modules, including micro-cracks, fragments, cold solder joints, dead cells, broken grids, and mixed cells. These internal issues can significantly reduce the service life and power generation efficiency of solar panels, and in severe cases, may even cause fires, leading to economic losses for the owners. This tester is compact, portable, and easy to install, capable of performing rapid inspections in various environments, providing strong technical support for power engineering supervision.