Development of Daylight Photoluminescence Technique for Photovoltaic Modules and Investigation of Temperature Dependency

Large‐Scale Daylight Photoluminescence: Automated Photovoltaic Module Operating Point Detection and Performance Loss Assessment by Quantitative Signal Analysis

“…γ PL;HJT aligns with the experimental findings from Ref. [9]. The higher cell voltage resulting in a negative temperature dependency of the luminescence signal intensity is not in line with findings by Zafirovska et al [21] who show a negative temperature coefficient, independently of the cell voltage.…”

“…Guada et al [8] as well as Solarzentrum Stuttgart [7] work with devices that have to be installed into the string to alter the OP of connected PV modules. Koester et al [9] used devices in the field to switch from MPP at normal operation to OC by turning off the inverter or MPP tracker, or disconnecting the string via combiner box switches. A similar approach is used by Vukovic et al modulating the OP of an inverter remotely, [11] and further by exploiting the automatic IV sweep in modern inverters.…”

“…Alternating image acquisition reduces the impact of changing irradiance during the imaging process, but it requires a very precise synchronization between the camera and the OP switching device, or a postprocessing step to separate images of different OPs, as reported by Alves dos Reis Benatto et al [13] Fast switching cannot be performed on PV modules using module-level optimizers. [14] While most approaches described above use the alternating method, Vukovic et al [12] and Koester et al [9] used the batched method. To reduce the impact of irradiance alteration during batched imaging, Bhoopathy et al [14] introduced intensity correction by comparing an unmodulated area of the recorded images (not active PV module surface, e.g., the ground, a wall in the background, or even the cell gaps in the same PV module).…”

“…Different methods were developed to switch between the two different OPs of a PV module. [6][7][8][9] In this work, a DPL-ready inverter, developed within H2020 project TRUST-PV, is presented, which enables toggling between OPs of the connected PV strings through preset parameters, without additional equipment or interference with the electrical layout of the PV plant. With the aspiration of using DPL from a UAV, semibatched imaging with subsequent automatic detection of recorded OP is developed to overcome synchronization issues between camera and inverter.…”