A new discrete approximation of the fractional-order operator

In this article a new discrete approximation of the fractional-order derivative/integral in the form of IIR filer is presented. This approach is based on power series expansion of Tustin rule to the IIR filter form. A Matlab function for this approximation technique is presented as well. Obtained results are applicable for practical implementation of the fractional order systems as well as the fractional order controllers.