Potential Induced Degradation (PID) poses a significant reliability issue in PV power plants, making it essential to assess products for their susceptibility to PID. The PIDcon system enables manufacturers to test their products as early as possible in the production process, starting at the solar cell level, and to evaluate the encapsulation materials as well. This allows for independent investigation of the solar cell and its SiNx layer, separate from the effects of the EVA and glass. The type of PID considered here involves shunting of solar cells due to high-voltage stress-induced leakage currents (PID-s).
To effectively classify solar cells, it is crucial to use sensitive EVA and glass materials so that the solar cell itself becomes the critical factor influencing the PID susceptibility of the entire stack. A lamination step can be added prior to measurement to enhance comparability with actual modules. The solar cells are connected using gold contact pins, which can be adjusted to fit the busbar design, even for island busbars.
The PIDStudio software allows users to set pass/fail criteria for the test, suggesting defaults based on IEC standards and insights from Fraunhofer CSP scientists.
Fig. 1: Solar cell with EVA foil and glass placed in a PIDcon
