ROBUST FREQUENCY-DOMAIN IDENTIFICATION

In this paper, a robust frequency domain identification technique is presented. The method is based on a frequency sampling filter (FSF) representation of the process. The FSF model has been combined with a standard least-squares estimator to directly obtain an estimate of the process frequency response. The identification technique is robust in the sense that a bound on the modelling error in the frequency domain is also provided using only input-output process data and prior knowledge of the distribution of the process disturbances. Simulation and experimental results using a pilot-plant heat exchanger are presented to illustrate the method.