PV modules with variable ideality factors

The classical single-exponential I-V curve model for crystalline-Si PV devices assumes a constant ideality factor. The model is widely applied in e.g. modeling the power output of PV systems at different irradiances and temperatures, and also in calculating the Equivalent Cell Temperature (ECT) from the open-circuit voltage. The present paper presents results from several crystalline-Si (c-Si) module types suggesting that the ideality factor may change with irradiance. The possible implications of such variability are discussed, in particular the need for a new ECT calculation procedure as well as for revision of some PV performance models.

[1]  Martin A. Green,et al.  24% efficient silicon solar cells , 1990 .

[2]  Harald Müllejans,et al.  A validation study of photovoltaic module series resistance determination under various operating conditions according to IEC 60891 , 2012 .

[3]  G. L. Araújo,et al.  The effect of distributed series resistance on the dark and illuminated current—Voltage characteristics of solar cells , 1986, IEEE Transactions on Electron Devices.

[4]  Ole-Morten Midtgard,et al.  Equivalent cell temperature calculation for PV modules with variable ideality factors , 2012, 2012 38th IEEE Photovoltaic Specialists Conference.

[5]  William E. Boyson,et al.  Photovoltaic array performance model. , 2004 .

[6]  H. Beyer,et al.  Mapping the performance of PV modules, effects of module type and data averaging , 2010 .

[7]  Wim C. Sinke,et al.  Explanation of high solar cell diode factors by nonuniform contact resistance , 2005 .

[8]  Paula Mints.  The commercialization of thin film technologies: Past, present and future , 2010, 2010 35th IEEE Photovoltaic Specialists Conference.

[9]  Geoffrey C. Ward,et al.  The year of the tiger , 1998 .

[10]  Ralf Preu,et al.  Series resistance characterization of industrial silicon solar cells with screen‐printed contacts using hotmelt paste , 2007 .

[11]  T. O. Saetre,et al.  Development of a test station for accurate in situ I-V curve measurements of photovoltaic modules in Southern Norway , 2011, 2011 37th IEEE Photovoltaic Specialists Conference.

[12]  D. Macdonald,et al.  Reduced fill factors in multicrystalline silicon solar cells due to injection‐level dependent bulk recombination lifetimes , 2000 .

[13]  Guy Beaucarne,et al.  WAFER-BASED CRYSTALLINE SILICON MODULES AT 1 €/WP: FINAL RESULTS FROM THE CRYSTALCLEAR INTEGRATED PROJECT , 2009 .

[14]  A. W. Blakers,et al.  Improvements in silicon solar cell efficiency , 1986 .

[15]  Martin A. Green,et al.  A new method for accurate measurements of the lumped series resistance of solar cells , 1993, Conference Record of the Twenty Third IEEE Photovoltaic Specialists Conference - 1993 (Cat. No.93CH3283-9).

[16]  Andrew Blakers,et al.  Accurate series resistance measurement of solar cells , 2013 .

[17]  André Mermoud,et al.  Performance Assessment of a Simulation Model for PV Modules of Any Available Technology , 2010 .

[18]  D. Macdonald.  Recombination and Trapping in Multicrystalline Silicon Solar Cells , 2001 .

[19]  P. Altermatt.  Silicon Solar Cells , 2005 .

[20]  Martin A. Green,et al.  General temperature dependence of solar cell performance and implications for device modelling , 2003 .

[21]  Tor Oskar Saetre,et al.  Series resistance determination and further characterization of c-Si PV modules , 2012 .

[22]  Keith R. McIntosh,et al.  Series resistance as a function of current and its application in solar cell analysis 37th IEEE photovoltaic specialists conference , 2011, 2011 37th IEEE Photovoltaic Specialists Conference.

[23]  R. Brendel,et al.  Evaluation of Series Resistance Losses in Screen-Printed Solar Cells With Local Rear Contacts , 2011, IEEE Journal of Photovoltaics.

[24]  Ole-Morten Midtgard,et al.  Extracting parameters from semi-log plots of polycrystalline silicon PV modules outdoor I–V data: Double-exponential model revisited , 2010, 2010 35th IEEE Photovoltaic Specialists Conference.

[25]  M. Green,et al.  Spatially resolved analysis and minimization of resistive losses in high-efficiency Si solar cells , 1996 .

[26]  D. Neuhaus,et al.  Industrial Silicon Wafer Solar Cells , 2007 .

[27]  Ole-Morten Midtgard,et al.  Two-Diode Model Revisited: Parameters Extraction from Semi-Log Plots of I-V Data , 2010 .

[28]  O. Midtgård,et al.  Modeling and parameter identification of crystalline silicon photovoltaic devices , 2011, PVSC 2011.

[29]  David L. King,et al.  The effect of uncertainty in modeling coefficients used to predict energy production using the Sandia Array Performance Model , 2010, 2010 35th IEEE Photovoltaic Specialists Conference.

[30]  P. Altermatt,et al.  Loss analysis and improvements of industrially fabricated Cz-Si solar cells by means of process and device simulations , 2011 .

[31]  Thomas Huld,et al.  Mapping the Performance of PV Modules of Different Types , 2009 .

[32]  A. Mette,et al.  A review and comparison of different methods to determine the series resistance of solar cells , 2007 .