Electroluminescence inspection system from Vitronic provides solar cell defect management

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  The VINSPECsolar electroluminescence inspection system detects inactive areas, cracks, weak active cells, cracks effecting electrical performance, micro-cracks and grid line interruptions.

Vitronic’s VINSPECsolar electroluminescence inspection system is designed to detect defects within solar cells that could influence electrical performance of the solar module. By using electroluminescence inspection, all defect areas are automatically detected, displayed and classified by relevant software before lamination, so that reworking can increase the module's efficiency. Archived electroluminescence images of the finished module also serve as proof of the delivered quality.

Problem

In module production, cells, strings, matrices all the way to modules are subjected to mechanical and thermal stresses. Missing electrical connections or wrong wiring can also occur during soldering. In addition, the solar cells used could display quality deviations depending on where they were purchased.

Solution

The VINSPECsolar electroluminescence inspection system detects inactive areas, weak active cells, cracks effecting electrical performance, micro-cracks and grid line interruptions. The inspections can be conducted on the solar cell string and solar cell matrix before or after lamination as well as on the finished module. This makes it possible for the module manufacturer to intervene and implement improvements before lamination, thereby optimizing the module's performance. A classification of the modules, based on the electroluminescence inspection, takes place after lamination and the images are saved as proof of the quality.

Applications

Detecting inactive areas, weak active cells, cracks effecting electrical performance, micro-cracks and grid line interruptions.

Platform

The electroluminescence process involves stimulating the solar cell string or module with electricity. Special cameras require only about one second illumination time to capture the weak light emissions of the cell as an electroluminescent image. An automated image assessment, using specially-developed software methods (e.g. micro-crack detection) takes place in order to then displays the defect areas on a monitor. The image is displayed on monitors of e.g. 46'' in size and can also be made available to reworking stations. The frequency of the individual defect characteristics is recorded and evaluated using the integrated statistics function.

Availability

January 2012 onwards.