دانلود رایگان مقاله انگلیسی روش حداقل مربعات خطی دو مرحله ای برای استخراج پارامترهای مدل دیود یکپارچه فتوولتائیک - نشریه IEEE

Abstract

In this paper a new method to calculate the five parameters of the single-diode model of a photovoltaic cell or panel is presented. This new method takes into account the intrinsic properties of the model equation and the technique of linear least-squares fitting, so, the computational complexity and costs are very low. Moreover, the proposed method, named Two-Step Linear Least-Squares (TSLLS) method, is able to work absolutely blindly with any kind of I-V curve. It does not need initial guesses at all and, consequently, it is not necessary to know previously any information of any parameter. The proposed method provides the parameters of the singlediode model just using the coordinates of N points (N≥5) of the I-V curve. The results provided by this method in a first stage have the same order of accuracy of the best documented methods in the field of parameters extraction, but, furthermore, in a second stage the best accuracy documented until now is obtained in two important case studies usually used in the literature as well as in a largescale I-V curve repository with more than one million of curves.

V. CONCLUSIONS

In this paper, a new method to identify the five parameters of the single-diode model of a photovoltaic cell or panel is presented. This new method, named TSLLS, makes use of the specific geometrical properties of the I-V curve to directly extract the parameters from a set of I-V points. At least five points are needed to apply the method but, in general, more accurate results are obtained when more points are used. The great advantage of the TSLLS method, in comparison with other methods available in the literature, is its ability to work absolutely blindly. It does not need initial guesses at all and it is not necessary the knowledge of any information of any parameter (like MPP, Isc or Voc), for this reason it can be fully automated to work with any I-V curve.

The results provided by the TSLLS method have the same order of accuracy of the most accurate methods proposed in the literature, but, furthermore, in a second stage applying a refinement to the solutions obtained by the TSLLS method, the best accuracy documented until now in the literature has been obtained in two important case studies usually used in the literature.

The potential of the TSLLS method has been also demonstrated modeling 1025599 I-V curves from the NREL repository with the best precision documented until now and working completely blindly from the data.

In order that any interested researchers can test the TSLLS method with their own curves, a webpage has been developed (pvmodel.umh.es) where the method can be directly tested online.