光伏组件所用材料的测量程序 第2部分：聚合物材料 前板和背板

[中文适用范围]： 本部分 IEC 62788 规定了用于地面光伏组件的非刚性聚合物材料（作为聚合物前板和背板）的安全和性能相关特性（机械、电气、热、光、化学）的测试方法和数据表报告要求。 本文件中的测试方法定义了如何以代表其在组件中使用方式的方式来表征前板和背板材料及其组成部分，这最终包括与其他匹配组件（如封装剂或粘合剂）的组合。在前板或背板组件级别进行所有表征和耐久性测试是不切实际的。相反，测试直接在这些组件上或在类似于光伏组件加工条件（即层压）下制备的专用测试样品上进行。 本文件中描述的测试结果被 IEC 62788-2-1 用于聚合物前板和背板在组件级别的安全认证，并支持在光伏组件级别定义的安全和性能相关测试，如 IEC 61730（安全）和 IEC 61215（性能）系列所定义。本文件还定义了评估聚合物前板和背板或其组成部分固有材料特性的测试方法，这些方法可能在数据表报告中需要，或在光伏组件产品开发或设计中有用。 背板在光伏（PV）组件的背面提供电气绝缘，在环境应力因素和使用条件下，在组件的预期寿命期间。前板在组件的阳光照射侧具有相同的功能。两者可以由玻璃或聚合物材料制成。 聚合物前板和背板通常是分层材料的组合，如薄膜、粘合剂或涂层，其中至少一个材料层提供电气安全所依赖的绝缘（RUI）。其他层可以提供对 RUI 的额外保护，防止环境因素或提供粘合功能。作为光伏组件的组成部分，前板或背板在光伏组件的其他组件（如太阳能电池、电路和连接器、封装剂、密封材料和接线盒）存在的情况下提供耐用的电气绝缘功能。这些元素可能对前板或背板引入额外的应力（例如通过化学相互作用或引入热负荷或机械应力）或改变环境应力（例如过滤到达背板阳光照射侧的紫外线辐射）。 本文件中的材料表征在未老化样品（经过热预暴露后）或加速老化后进行，包括热氧化老化（热耐久性和失效安全测试）、水解老化（湿热）、光解老化（紫外线老化）、磨损和顺序紫外线老化加热循环。 刚性聚合物片材（也提供机械支撑）可能需要进一步考虑，这超出了本文件的范围。 [外文原描述]： IEC TS 62788-2:2024 defines test methods and datasheet reporting requirements for safety and performance-related properties (mechanical, electrical, thermal, optical, chemical) of non‑rigid polymeric materials intended for use in terrestrial photovoltaic modules as polymeric front- and backsheets. The test methods in this document define how to characterize front- and backsheet materials and their components in a manner representative of how they will be used in the module, which eventually includes combination with other matched components such as encapsulants or adhesives. Results of testing described in this document are called by IEC 62788-2-1 for safety qualification of polymeric front- and backsheets on component level and support the safety and performance-related tests defined on the PV module level as defined in the series IEC 61730 (for safety) and IEC 61215 (for performance). This document also defines test methods for assessing inherent material characteristics of polymeric front- and backsheets or their components, which can be required in datasheet reporting or can be useful in the context of product development or design of PV modules. This second edition cancels and replaces the first edition published in 2017. This edition includes the following significant technical changes with respect to the previous edition: a) With revision of IEC 61730-1 the requirements for the polymeric front- and backsheet have been moved from IEC 61730-1 into IEC 62788-2-1. This is reflected accordingly. b) The tensile testing method has been refined based on findings of round robin tests, including updated drawings. c) A thermal pre-exposure method has been introduced to be equivalent to the thermal effects of a "lamination" cycle. This pre-exposure defines the "fresh" state of the front- or backsheet in final application for evaluation of changes in ageing tests. For practical reasons, an oven exposure has been defined as an equivalent test. d) The multiple functions of the lamination protrusion test (previously DTI test) have been clarified, to identify and measure RUI layer thickness as well as to identify layers for which the comparative tracking index (CTI) needs to be determined. Also the content of IEC 62788-2-1 has been updated, by which the lamination protrusion test and MST 04 are additionally set in perspective to each other via engineering judgement. e) The DC breakdown voltage test method has been updated and the option to perform a withstand voltage test has been added (to reduce the required measurement voltage). The correction of DC breakdown voltage ( ) measurements, needed in the presence of non‑RUI layers and after the lamination protrusion test, has been defined more precisely. f) Details for thickness measurement have been added (engineered surface roughness due to embossing). g) The adhesion test methods have been reviewed and updated. The single cantilevered beam test has been added. Figures have been updated to align with IEC 62788-1-1. h) The thermal failsafe test has been added as a test method based on discussion in the parallel project for IEC 62788-2-1. The test method offers a single temperature-point evaluation to include elongation at break to the thermal endurance evaluation. I) A sequential UV/TC test ("solder bump test") has been added.