Frequency-domain approach to continuous-time system identification: Some practical aspects

Abstract

Since the end of the 1950s - beginning of the 1960s - the control society developed for its control designs a technique to build discrete-time models of continuous-time processes. Due to its overwhelming success a classical timedomain school emerged, and its authority in the field of system identification was soon widely recognised. The continuous-time identification methods developed in the early days of system identification [30, 67] got into a tight corner, and were ‘forgotten’ for several decades. Nowadays many people select discrete-time models and classical time-domain identification methods to solve their particular modelling problems. If the input is zero-order-hold, then discrete-time models are the natural choice, however, in all other cases continuous-time models might be preferred. Also, if the final goal is physical interpretation, then continuous-time modelling is the prime choice.