A method for solving five parameters of photovoltaic modules by using lambert function

Abstract

The invention provides a method for using a Lambert function to solve five parameters of a photovoltaic module. The method specifically comprises the steps of 1, establishing an output characteristic model of the photovoltaic module, and obtaining a current characteristic equation of the photovoltaic module; 2, utilizing the Lambert function to transform the current characteristic equation of the photovoltaic module; 3, utilizing electrical characteristic parameters measured in the actual working environment by the photovoltaic module to solve a curve fitting factor a, and sequentially estimating I0, Rs, Rsh and IL; 4, conducting iterative optimization on the Rsh value, and on the basis of the value of Rsh, sequentially optimizing the values of Rs, I0 and IL; 5, converting the values of Rs, I0 and IL after iterative optimization under the actual working conditions in the step 4 into I0, ref, Rs, ref, Rsh, ref, and IL, ref under standard conditions; 6, adopting a linear planning method to conduct integrated extraction on multiple groups of data to obtain the five final parameters of the photovoltaic module including I0, ref', Rs,ref', Rsh, ref', IL,ref' and a. Through the adoption of the method for using the Lambert function to solve the five parameters of the photovoltaic module, the iterative calculation amount is reduced, and the calculation process is simplified; meanwhile, the differential values of the current equation at the open-circuit and short-circuit places do not need to be known in advance.

Description

technical field [0001] The invention discloses a method for solving five parameters of a photovoltaic module by using a Lambert function, belonging to the technical field of photovoltaics. Background technique [0002] The practical application of photovoltaic modules needs to analyze its precise output characteristics and work efficiency. However, the output model of photovoltaic modules is relatively complex, and the I-V characteristic curve of photovoltaic modules is very nonlinear. Therefore, the analysis of the output model formula of photovoltaic modules has great significance. great practical significance. On the basis of current research, photovoltaic modules can generally be equivalent to a five-parameter model of a single diode. This model has high output accuracy and has been generally recognized by the photovoltaic industry. [0003] The five-parameter model of a single diode includes the photogenerated current I L , Diode reverse saturation current I 0 , seri...

AI Technical Summary

Problems solved by technology

In recent years, the parameter extraction method of the five-parameter model of photovoltaic modules has become one of the hot issues in the field of theoretical simulation of photovoltaic modules. Among them, there is a typical method of cyclic determination of actual results proposed by Brano in 2010. This method can obtain more accurately The five parameters of the current equation, but the differential values ​​of the open circuit and short circuit current equations must be known under standard test conditions, and the calculation amount of the iterative process is too large; in 2009, domestic scholars Cheng Xiaohang et al. The transcendental equation is transformed into an algebraic equation to solve five parameters, which simplifies the calculation process, but the prerequisite is still to know the differential value of the current equation at the open circuit and short circuit

Images