Method for analyzing partial voltage of solar cell based on EL image

Abstract

The invention discloses a method for analyzing a partial voltage of a solar cell based on an EL image. Specifically, the method comprises the steps of applying a relatively low external voltage on a standard crystalline silicon solar cell to obtain an electroluminescence image of the standard solar cell under the voltage; measuring the partial electroluminescence intensity of the standard solar cell; calculating to obtain a calibration coefficient; applying a higher external voltage on the solar cell to obtain the electroluminescence image of the solar cell; measuring the partial electroluminescence intensity; and obtaining the partial voltage of the solar cell through the partial electroluminescence intensity and the calibration coefficient. According to the method, the risk of generating a hot spot can be reduced by analyzing the partial performance of the cell through the EL image, thereby improving the reliability of the assembly.

Description

technical field [0001] The invention relates to a method for analyzing the local voltage of a battery sheet based on an EL image, and belongs to the technical field of photovoltaic modules. Background technique [0002] With the rapid development of the domestic solar photovoltaic industry in recent years, and with the rapid growth of photovoltaic system installation capacity, the problems of operational safety and reliability of photovoltaic systems have gradually emerged. Due to defects in the battery itself or human factors, the output current of the solar cell may be reduced, causing its two ends to be reverse-biased, resulting in local overheating, resulting in permanent failure of the photovoltaic module and reducing the life of the photovoltaic module. [0003] However, solar cell defects such as cell microcracks caused by mechanical loads, cell black chips caused by low-purity materials and cell technology, point defects caused by crystal dislocations, etc., may caus...

AI Technical Summary

Problems solved by technology

Due to defects in the battery itself or human factors, the output current of the solar cell may be reduced, making its two ends in reverse bias, resulting in local overheating, resulting in permanent failure of the photovoltaic module and reducing the life of the photovoltaic module

[0003] However, solar cell defects such as cell microcracks caused by mechanical loads, cell black chips caused by low-purity materials and cell technology, point defects caused by crystal dislocations, etc., may cause local high temperature of photovoltaic modules under the condition of non-uniform radiation distribution. , but the specific research on the influence of defects on the current and voltage of cells has not been studied in depth. Therefore, it is very important to provide a method to use EL images to study the local voltage of cells, which is very important for further analysis of the failure mechanism of defective cells on photovoltaic modules.

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