STABILITY PRESEVVATION PROBLEM IN THE METHODS THAT FIND RATIONAL APPROXIMATION OF FRACTIONAL ORDER SYSTEMS

This paper deals with stability preservation issue in methods which present an integer order model as an approximation of a fractional order system. First, the stability region of the approximating model obtained in these methods is determined and compared with the stability region of the original system. Then, one of the popular methods in this category (Charef's method) is studied from the stability preservation point of view. Key word