APPARATUS AND METHOD FOR INVESTIGATING THE CURRENT FLOW DISTRIBUTION IN SOLAR CELLS AND SOLAR MODULES

摘要

The invention relates to an apparatus and a method for investigating the current flow distribution in solar cells and solar modules for defects. The object is to provide an apparatus and a method which in a short period of time provides an indication of defects and in addition provides their precise position. According to the invention, a current flow, self-excited or externally excited, is produced in the conductor tracks and contact-making or interconnection elements. A magnetic field of a certain level is formed around each conductor track and around the contact-making or interconnection elements. These magnetic fields are sensed and detected by means of magnetic field detectors. The current flow distribution at any point in one of the solar cells and solar modules to be tested can therefore be determined indirectly via the current produced and the magnetic field being formed. At the same time, the surface of magnetic field sensors is sampled. The magnetic field data determined by the magnetic field sensors are sensed precisely in terms of position and are buffer-stored by means of microcomputers. A precise image of the current flow distribution is produced from these magnetic field data, and this image can be displayed on conventional display media or outputted by means of suitable connected devices. The apparatuses and the method can be used to reduce the rejects quota for solar cells or plate-shaped solar modules in mass production.