户外光伏组件接线盒鼓包失效分析

BULGE FAILURE ANALYSIS OF OUTDOOR PV MODULE JUNCTION BOX

针对中国西北地区某户外光伏电站中光伏组件出现的接线盒鼓包情况,拆取正常光伏组件至实验室进行接线盒旁路二极管短路电流下热性能等的模拟测试分析。结果表明:热逃逸测试后,接线盒旁路二极管性能仍能满足相关国际标准的要求;接线盒鼓包与旁路二极管反向电流过载下的热性能无直接关系;接线盒鼓包与长时间短路电流Isc下的热性能有关,在2.5Isc下,接线盒旁路二极管产生超过220℃的高温,累积的热量引起灌封胶发黄熔化,从而导致接线盒出现鼓包失效现象。

This paper focuses on the problem of junction box bulging in PV modules of an outdoor PV power station in Northwest China.Normal PV modules are removed and sent to the laboratory for simulation testing and analysis of thermal performance under short-circuit current of the junction box bypass diode.The results indicate that after the thermal runaway test,the performance of the junction box bypass diode can still meet the requirements of relevant international standards.The junction box bulging is not directly related to the thermal performance of the reverse current overload of the bypass diode,but it is related to the thermal performance under long-time short-circuit current(I sc).At 2.5I sc,the bypass diode of the junction box generates a high temperature exceeding 220℃,and the accumulated heat causes the sealing adhesive to turn yellow and melt,resulting in bulging failure of the junction box.