Shift-and-scale model reduction: An alternative stability-preserving approach

Abstract

A new stability-preserving model order-reduction method is presented for continuous-time systems. It makes use of the relatively new idea of transformed whole-system parameter matching for calculating the poles of the reduced-order transfer function. This has the advantage of using more of the system information than traditional methods in the approximation of the poles. The method is seen to be flexible and computationally attractive, relying only on readily available algorithms. It is based on a shift-and-scale transformation of the transfer function before applying the order-reduction process. Further, it is shown to be a viable alternative to existing stability-preserving techniques. Some examples illustrate the method.