Analysis of closed-loop identification with a tailor-made parameterization

An analysis is made of a closed-loop identification scheme in which the par ameters of the plant model are identified on the basis of input and output measurements of the closed-loop system. The closed-loop transfer function i s parametrized in terms of the parameters of the open-loop plant model, and utilizing knowledge of the implemented feedback controller. This is denote d as a tailor-made parametrization as it is tailored to the specific feedba ck structure at hand. Consistency of the plant estimate is shown to hold ti nder additional conditions, resulting from the requirement that the paramet er set should be a connected set. Sufficient conditions for this requiremen t are formulated, requiring the controller order not to exceed the order of the plant model.