局部阴影遮挡的太阳电池组件输出特性实验研究

EXPERIMENTAL STUDY ON CHARACTERISTICS OF PARTIAL SHADED SOLAR MODULE

结合太阳电池双二极管与雪崩击穿效应数学模型,设计太阳电池组件遮挡实验,并对组件性能进行实际测试。分别在有、无旁通二极管两种情况下,分析比较单片太阳电池小比例(1%～10%)、大比例(10%～100%)遮挡及多片电池阴影遮挡的太阳电池组件输出的I-V及P-V特性曲线。结果表明,有、无旁通二极管情况下,组件单片电池被遮挡1%～10%,整个组件输出功率下降比例均不超过2%,同一串电池片之间可允许存在小的功率差异或表面辐照强度差异(<5%)。同组件无旁通二极管多个电池遮挡实验显示,电池出现热斑效应时会被反向击穿,实验组件击穿电压约15V,为避免热斑损害,组件中应对少于15/0.6=25片串联电池并联一个旁通二极管。

Basing on the theoretical calculation and analysis, experiments for shading test of module were designed in this paper. I-V （current and voltage） and P-V （power and voltage） characteristics of modules were tested and analyzed when one or multi cells were shaded by low percentage shading （ 1% ~ 10% ） and large percentage （ 10% 100% ） in which by-pass diodes would be designed or not. According to the test result, the output power（Pro） of solar module decreased slightly （less than 2% ） while one of cells was shaded by 1% -10% in the module. So slightly difference among power of cells or asymmetrical radiation （ 〈 5% ） on cells＇ surface in one module is ac- ceptable. It was shown in the multi-cell shading test that cell would be destructed by reverse current while the re- verse voltage reaches 15V when hot spot emerged. To avoid hot spot damage, it is necessary to connect at least one by-pass diode to the string as the pieces of cells is less than of 25 （ 15/0.6 = 25）.