Research On Reliability Evaluation Of Solar Panel Based On Low Frequency Noise Test

Solar energy is one of the most widely used new energy,which may change our lives in the future.As the most direct and effective means of solar energy utilization,solar cells are extensively used in our daily life.But its working environment is often harsh outdoor environment,even the space environment with high radiation and huge temperature changes.Therefore,the reliability of solar cells is required to be higher and higher.The traditional reliability screening methods of solar cells are mainly to age or apply external stress,which is time-consuming,costly and destructive,and the results are not accurate.Since the discovery of 1/f noise in the last century,more and more scholars have studied the defect related and highly sensitive low-frequency noise as a means to characterize the reliability of electronic materials or devices.At present,low-frequency noise testing has been successfully applied to the reliability screening of transistors,optoelectronic coupling devices,semiconductor lasers and other electronic devices.However,the research of low-frequency noise as a means to characterize the reliability of solar cells is still in its infancy,and there are still some problems.1)There is no complete set of standards for low-frequency noise test of solar cells,including experimental environment,test circuit and test parameters,etc.2)There is no complete set of low-frequency noise testing system for solar cell modules.3)At present,the research of low-frequency noise characterizing the reliability of solar cells mainly focuses on the time-domain and low frequency noise voltage point frequency,which is single and has errors.To this end,this paper studies the following aspects from the principle of low-frequency noise generation.1)Research on low-frequency noise measurement of solar cellsAccording to the industry,national and international standards and the actual demand,we proposed a set of low-frequency noise test method for solar cells in the form of industry standards.This method puts forward the requirements of low-frequency noise test environment and equipment conditions,provides two basic noise test circuit and five common calculation methods of low-frequency noise analysis parameters.2)Design of the low-frequency noise test system of solar cells.The system includes hardware system and software system.The design of hardware circuit adopts balanced bridge structure,current noise spread spectrum amplification technology and parallel low noise voltage amplification technology to improve the system test voltage bandwidth and reduce the system noise;The software system is designed based on LabVIEW.It can collect the low-frequency noise of solar cells in time domain and frequency domain,and analyze,save and print the collected results.The system also has the sample reliability screening function based on different low-frequency noise parameters.3)Research on reliability classification of solar cells based on low-frequency noise.Solar cell samples were selected for low frequency noise test and aging test.The combination of low-frequency noise voltage point frequency value,bandwidth noise voltage and 1/f noise amplitude is proposed as the criterion of reliability classification of solar cells,and it can guide the selection and classification.