Development of a portable electroluminescence measurement system for photovoltaic modules



Investigations of PV modules benefit from electroluminescence (EL) imaging technique is widely used indoors and outdoors. This technique enables to identify inactive and defective cell areas as well as varying series resistance contributions. PV modules are measured in forward bias condition, i.e., by forcing current flow through the module with an external power supply. The EL signal is then detected by a camera.

An electric DC power supply capable of applying Isc of the module of interest is required. The power supply must be able to provide sufficient voltage to achieve the short-circuit current ISC of the module (typically around 10 A). Depending on the module technology, the required voltage may be approximately equal to the open circuit voltage VOC of the module (typically around 50 V).

This project will develop a portable EL measurement system enabling for measuring individual modules. To enhance image quality, a modulation needs to be integrated (illustrated in the figure below): A sequence of “dark” (no current through module) and “bright” (current through module) are taken. The average of the difference (bright – dark) of this image sequence allows to filter out noisy background.

If you are interested in this project, please get in contact:



In your project, you will develop:

  • A modulator setup that integrates with a camera (i.e. triggers the camera in dark/bright sequence), and with a current source.
  • A current source based on a portable Li-Ion battery, that is integrated in the modulator. The current needs to be variable.
  • Overall system control could be either through a separate laptop, or a single-board computer (e.g. Raspberry Pi).


  • Electronic skills and use of hand tools.
  • Programming knowledge, for example using RaspberryPi or Arduino board for the modulator.


Updated:  10 August 2021/Responsible Officer:  Dean, CECS/Page Contact:  CECS Marketing