Improved Eddy-Current Probe for Non-Destructive Characterization of Electrical Contacts in PV Modules

Within this work we are presenting an improved eddy-current based analysis method for the inspection of electrical contacts and solder joints in PV modules. The basic concept as well as first results were already shown at last year’s EU PVSEC 2020. The concept proofed that a fast, non-destructive (contactless) and portable characterization without powering a PV module is feasible. Hence, it has the potential to be used as handheld, contact free inspection system for O&M applications on site, as well as an industrial tool for quality control and process monitoring directly inside of the PV production line. Within the Austrian flagship project “Sustainable Photovoltaics” further research is carried out aiming to improve this eddy-current analysis method. In a first step towards an improved system, an enhancement version of the sensor probe was developed by changing the single coil configuration to a multi coil setup. Due to the specific design, the system is eliminating negatively influencing effects and because of the differential measurement approach high gain factors are possible to increase the systems sensitivity.