Reliability Assessment Method For PV Modules Base On λ-distribution Uniform Expression

Reliability of PV modules is one of the important factors that affecting the service life of the photovoltaic system. The present research on photovoltaic component reliability assessment mainly focus on analysis of the external stress influence on life of PV parts, or build the prediction model from empirical data. This paper takes "Reliability assessment method for PV modules base on λ- distribution Uniform Expression" as the title, proposes a method of using λ-Distribution Uniform Expression to evaluate the reliability of PV modules, and provides a new idea for the reliability assessment of crystalline silicon PV modules, and it has a certain academic value to the development of life assessment theory of the PV modules and other electronics. Research work was funded by science & technology project for Administration of Quality and Technology Supervision of Guangdong Province.This paper analyzed crystalline silicon PV modules failure mechanism and influencing factors, and the reliability assessment model for main part of PV modules is established, then the evaluation method of photovoltaic component reliability base on λ-Distribution Uniform Expression is proposed. At last, it write the program to simulate the model, and analyzes the test results. The main work of the thesis includes:(1) The physical structure of crystalline silicon PV module composition is proposed, and the performance requirements on each parts of PV module is described, including the failure mechanism of EVA, backplane, welding zone and junction box, and analyzes the impact to PV modules reliability in practical working condition of ultraviolet-radiation, temperature and humidity, etc.(2) Analyzing the photovoltaic components reliability evaluation model based on the classical distribution. Establish reliability assessment model of EVA, backplane, junction box based on Weibull distribution; Use exponential distribution as the basis, research the application of voting-method in the reliability modeling of photovoltaic components, and establish a reliability evaluation model of welding base on exponential distribution and voting-method, then select the parameters of this model to analyze its result of simulation use base on simulation software Matlab.(3) For there is no effective model to evaluate photovoltaic component reliability at present, put forward to an evaluation method of photovoltaic component reliability based on λ-Distribution Uniform Expression. Study on Logical structure model under the photovoltaic component failure analysis of PV parts, and research the reliability analysis model of PV modules. Make an interpretation of statistical characteristics of λ-Distribution Uniform Expression, put forward to the basis and construction steps of assessment model of PV modules based on λ-Distribution Uniform Expression.(4) Study on parameters selecting of photovoltaic component reliability evaluation model based on λ-Distribution Uniform Expression, then write the program of it using Matlab simulation software, and make a brief analysis of the simulation results of this model.The simulation results show that, the PV modules reliability model of photovoltaic modules based on λ-Distribution Uniform Expression has the very good fitting effect for different parameters of PV parts, which is suitable for the reliability evaluation of photovoltaic components. The model can guarantee reliability assessment effect of PV modules, at the same time, effectively simplify the steps of reliability PV module evaluation, it would applicable to evaluation of reliability of crystalline silicon PV component in different environments.