Throttle body: Modelling and identification

Abstract

Abstract

Mathematical modelling of the throttle body air flow is one of the steps in generating a generic spark ignition (SI) engine model for control-oriented development. Typically, the throttle body flow model is subdivided into components: a one-dimensional isentropic flow law, an empirically derived effective area component and a closed plate leakage term. Of these, only the effective area term presents any difficulty. This paper describes the mathematical formulation and analysis of a generic model for the throttle body. Once the model is formulated, the experimental procedure for the identification and estimation of the numerical values of the elements within the model is described. The primary focus of the analysis procedure is the statistical modelling methods associated with calibrating the effective area term. Non-linear repeated measurement analysis methods are used for this purpose.