loading page

String-to-String Coupling Within a Large Photovoltaic Module: Measurement and Circuit-Computational Electromagnetic Hybrid Modelling
  • Kurt Coetzer ,
  • Pieter Gideon Wiid ,
  • Arnold Rix
Kurt Coetzer
Stellenbosch University, Stellenbosch University

Corresponding Author:[email protected]

Author Profile
Pieter Gideon Wiid
Author Profile
Arnold Rix
Author Profile

Abstract

Large photovoltaic (PV) modules comprise multiple series-connected internal strings, which are in turn composed of series-connected PV cells. When excited with time-varying signals, the loops formed by these internal strings couple to each other. Until now, this coupling has not been considered in any radio frequency interference studies of PV systems. This article examines this coupling both practically and computationally as follows. Firstly, the loop-to-loop coupling within a large (310 W) PV module is quantified through a careful series of low-frequency vector network analyser measurements – the first novel contribution of the study. Secondly, a recently-proposed circuit-computational electromagnetic hybrid methodology is applied to this coupling problem, investigating it computationally â\euro“ the second novel contribution of the study. The four newly-formulated PV models which utilise this hybrid methodology are assessed, as well as two literature-based models. Thirdly, a comparison of the measured and simulated results is performed â\euro“ the third novel contribution of the study. This crucial validation step is performed by examining the scattering parameter results, both visually and by means of the acclaimed Feature Selective Validation (FSV) method. The literature-based models exhibit poor FSV correlation in all cases, while the improved models show good-to-excellent FSV accuracy - a vast improvement.