Finite Element Analysis of Module Substructures

© Fraunhofer CSP
Animation of the module chassis deformation with changing wind load (+/- 1000 Pa), 5-fold cant.

The continuous price decline of solar modules, share in overall cost reduced from 2/3 to below 1/3 in some cases, leads to increased focus on other components (mounting frame, inverter, electrical work and equipment, assembly & scaffold) of a PV-System. Fraunhofer CSP with its expertise in finite element simulation offers the opportunity to analyse substructures and their interaction with the PV modules. This opens possibilities for optimization regarding cost of materials.

For the simulation models with different levels of detail are set up. The deformation of the whole mounting frame with the modules is simulated under different load scenarios, like temperature, snow or wind loads to determine the stress of the various components. Subsequent detailed simulations allow in-depth examination of e.g. mounting points and screwed connections. The objective is to find cost-effective solutions with standard parts and minimal material usage to further reduce overall costs. These models allow the investigation of loads on the modules in interaction with the substructure. In contrast to standard tests the flexibility of the mounting frame is considered, which may lead to a different load situation (e.g. by additional torsion) and can be incorporated in the analysis of cell breakage or other defects. With help of fluid dynamic simulations wind loads in the field can be further investigated. The inhomogeneous pressure distribution under real conditions might be more severe for the modules and should be considered for reliable designs.