Implementation of a Friendly Daylight Electroluminescence System for the Inspection of Solar PV Panels

Abstract

Electroluminescence (EL) is nowadays a well-recognized tool for the inspection of solar cells and panels, particularly interesting for the inspection of large plants. Routinely, when the modules are mounted at the PV site, EL measurements are carried out during nighttime and collected with Si CCDs (including conventional - modified - cameras), with good spatial resolutions and relatively low prices. However, daylight EL systems with InGaAs CCDs are promising tools for EL inspection, due to the possibility to analyse the solar panels during the day, which will be beneficial regarding the cost, practicability and module risk mitigation associated to the testing service. Also, in order to reduce production losses, the measurements should be conducted in a fast and reliable way. In this paper, we present a friendly daylight EL system using a cost-effective InGaAs CCD and appropriate filter setup. Good-quality images at high irradiations (above 1000 W/m2) can be obtained in less than 20 s. Additionally, high-quality photoluminescence (PL) imaging can be registered by this friendly, cost-effective system.