OPTICAL MODEL FOR THIN-FILM PHOTOVOLTAIC DEVICES WITH LARGE SURFACE TEXTURES AT THE FRONT SIDE

An optical model for simulation of thin-film photovoltaic devices with thick surface-textured front components is presented. The model is based on the combination of incoherent geometric optics and coherent wave optics analysis, which are employed separately to simulate light propagation through the front textured component and the bottom flat thin-film component of the device, respectively. The verified model is implemented into the optical simulator CROWM, which is employed to study the light-trapping potential of the front surface-textured protective glass in thin-film photovoltaic modules. The results show that the texturisation in the range of millimetres significantly improves the quantum efficiency of the PV module, which results in 14.3 % higher JSC compared to the conventional module with flat protective glass. Optični model za tankoplastne fotonapetostne strukture z velikimi površinskimi teksturami na sprednji strani Kjučne besede: tankoplastne silicijeve sončne celice, optično modeliranje, teksturirano steklo, metoda sledenja žarkov, metoda prenosnih matrik Izvleček: V članku je predstavljen optični model za simulacijo tankoplastnih sončnih celic in fotonapetostnih modulov z velikimi površinskimi teksturami na sprednji strani strukture. Model temelji na kombinaciji nekoherentne geometrijske optike in koherentne valovne optike. Prvo uporabljamo za simulacijo potovanja svetlobe skozi sprednjo teksturirano komponento strukture, drugo pa za simulacijo spodnje tankoplastne strukture. Verificirani optični model je implementiran v optičnem simulatorju CROWM (“Combined Ray Optics / Wave Optics Numerical Model”), s katerim preučujemo potencial teksturiranega zaščitnega stekla za izboljšanje svetlobnega ujetja v tankoplastnih fotonapetostnih modulih. Rezultati kažejo, da površinska teksturizacija sprednjega stekla v milimetrskem območju bistveno izboljšuje kvantni izkoristek modula, kar se odraža v 14.3 % višji kratkostični gostoti toka v primerjavi s konvencionalnim modulom z gladkim sprednjim steklom.

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