A MPPT Method Based on the Approximation of a PVM Model using Fractional Polynomials

This paper presents a non-traditional method for the approximation of the photovoltaic module, PVM, exponential model using fractional polynomials where the shape, boundary conditions and performance of the original system are satisfied. The proposed Maximum Power Point Method uses these fractional polynomials to obtain analytically the optimal solutions for the maximum power, Pmax for the PVM operation, optimal voltage, Vop, and optimal current, lop. Also, if the characteristics of the PVM array are known the method can be program in an Arithmetic Logic Unit, ALU, and estimate the maximum power measuring the open circuit voltage, V x and short circuit current, I x . Examples and simulations to validate the proposed MPPT are given in the paper using data sheet for different types of PVM´s. Finally, the proposed method is excellent to approximate the PVM exponential model and provide a different way to approximate exponential functions that are not possible to solve using differential calculus.