Contributions to the model reduction problem

A new method of model reduction is introduced based on the differentiation of polynomials. The reciprocals of the numerator and denominator polynomials of the high-order transfer function are differentiated suitably many times to yield the coefficients of the reduced order transfer function. An error analysis shows the accuracy of the method, and an eighth-order example illustrates it. The method is computationally very simple and is equally applicable to unstable and nonminimum phase systems.