Identification of a Hammerstein model for an aerospace electrohydraulic servovalve

Abstract This paper discusses the black-box identification of a real aerospace electrohydraulic actuator. A Hammerstein model structure is adopted due to its simplicity and capacity to represent a wide set of nonlinear phenomena. The identification strategy begins with a frequency-domain analysis so that a polynomial NARX model structure can be defined. Then, an extended least squares procedure is applied to obtain the coefficient values.