The quality of welding strip will directly affect the current collection efficiency of photovoltaic module, so it has a great impact on the power of photovoltaic module. The so-called photovoltaic welding strip is to coat binary or ternary low-melting alloy on the surface of copper strip with given specification.
The shading area of the photovoltaic welding strip is reduced by reducing the width of the main grid line and the PV welding strip, and the total amount of light received by the solar cell is increased. However, the contact resistance of the whole PV assembly is too large, which increases the electrical loss of the photovoltaic module.
The so-called photovoltaic welding strip is to coat binary or ternary low-melting alloy on the surface of copper strip with given specification. The methods of continuously and evenly coating low-melting metals and alloys on the metal strip include electroplating, vacuum deposition, spraying and hot-dip coating.
According to IEC61215 standard, the light emitted by solar simulator is vertically incident on the surface of photovoltaic welding strip through glass and EVA. The change of surface structure of photovoltaic welding strip will change the reflection path of light on the surface of photovoltaic welding strip, affecting the size of α 1 in Fig. 1.
In order to study the influence of the surface structure of heterogeneous welding strip on the power enhancement of photovoltaic module, three kinds of heterogeneous welding strips are selected for theoretical simulation. Meanwhile, a conventional welding strip is selected as the comparison sample.
These results show that the inclined plane of heterogeneous welding strip is imperfect, which is intensified during the welding process. The welding strip is an important part of photovoltaic module. The current of the cell is collected by welding on the main grid of the cell.