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This paper presents three sub-models of production Engine Management Systems software for turbocharged engines; 1) new load variable for volumetric efficiency modelling, 2) new pumping torque model, where 1) and 2) both solve non-monotonic behavior of traditional techniques for active boost controlled engines, 3) Compressor Recirculation Control requiring only the compressor surge-line for calibration.

An important paradigm for the modelling of naturally aspirated (NA) spark ignition (SI) engines for control purposes is the Mean Value Engine Model (MVEM). Such models have a time resolution which is just sufficient to capture the main details of the dynamic performance of NA SI engines but not the cycle-by-cycle behavior. In principle such models are also physically based, are very compact in a mathematical sense but nevertheless can have reasonable prediction accuracy. Presently no MVEMs have been constructed for intercooled turbocharged SI engines because their complexity confounds the simple physical understanding and description of such engines. This paper presents a newly constructed MVEM for a turbocharged SI engine which contains the details of the compressor and turbine characteristics in a compact way. The model has been tested against the responses of an experimental engine and has reasonable accuracy for realistic operating scenarios.

This paper presents production Engine Management System algorithms for Estimation and Control of Turbocharged engines with the following qualities; 1) Model based ensuring applicability at all ambient conditions, 2) Does not require Turbine data for calibration 3) Estimation logic form allows reuse for control applying predictive values for response and stability 4) Applies to all Waste-Gate types; passive and active, pneumatic and electrical, 5) Does not require Waste-Gate position measurement 5) Applies to engines with Variable Geometry Turbine.

A dynamic EGR State Estimator (ESE) intended for production engine management systems (EMS) implementation is presented. It better describes the development of external exhaust gas recirculation (EGR) concentration at the engine intake ports during EGR transients than traditional models. The dynamics of EGR concentration time and spatial development in the intake manifold are described as a perfect mixing model in the intake manifold plenum volume and non-mixing plug flow in the intake manifold runners. The time scale of EGR transients precludes the use of traditional EGR measurement techniques for model verification. Instead a wide range air fuel (WRAF) sensor is used. Results are shown for a large variation in operating conditions and compared to the performance of a traditional model.

Because there are no production-type sensors which are able to measure the flow directly at the intake port, it is becoming common practice to use models of varying complexity to infer the port air mass flow from other measurements. Given the tight requirements of modern air/fuel ratio (AFR) control strategies, the accuracy of these models needs to be better than ever, during steady-state of course (though λ feedback strategies are by design very robust), but mainly during transient operation. This paper describes why conventional models might be inaccurate during engine transients.

Mean Value Engine Models (MVEMs) are simplified, dynamic engine models which are physically based. Such models are useful for control studies, for engine control system analysis and for model based engine control systems. Very few published MVEMs have included the effects of Exhaust Gas Recirculation (EGR). The purpose of this paper is to present a modified MVEM which includes EGR in a physical way. It has been tested using newly developed, very fast manifold pressure, manifold temperature, port and EGR mass flow sensors. Reasonable agreement has been obtained on an experiemental engine, mounted on a dynamometer.