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Engineers developing powertrain control strategies are increasingly expected to build controls with greater functionality. At the same time pressures on unit costs are increasing, development schedules are tightening and higher results ratios are expected. Rapid prototyping Software tools are now available which help accelerate the development process. One such tool for engine control system design is CPower, (a numerical integration of GT-Power and Simulink). CPower allows prototypes to be developed and tested “on a desk” using a transient engine model which, unlike cycle-averaged engine models, reliably reproduces the engine operating characteristics, such as gas dynamics and complex combustion process. (Stobart et al,1998 ) To demonstrate this tool Arthur D. Little have developed a simple idle-speed control system for a light duty truck engine. Idle speed control is a well known problem although it often represents a significant development cost.

Diesel engine control has already become complex, and in order to meet future emissions standards (such as Euro 4) it is likely to be the control system that will provide the needed performance increment. Common rail fuel injection offers yet more degrees of freedom which will need to be exploited as new emissions standards emerge. Whatever the emissions standards, there is a need to reduce risk at the earliest stages in the development of the powertrain. This will involve early and extensive simulation of the powertrain including its control system, sensors and actuators. What is the best way to achieve this using current tools? The result lies in a combination of a phenomenological model of the engine and a flexible controls environment. To illustrate the principles of developing prototype control systems, we will use the example of the CPower environment, which is a combination of a detailed engine simulation code (GT-Power) and the Simulink simulation environment.

The information needs of engines have increased dramatically over recent years. In order to achieve the levels of performance and endurance that are now required in the marketplace, engine operation increasingly employs sophisticated control with closed-loop operation of various functions. This control trend will continue as performance expectations increase, calibration times reduce and systems become more complex and dependent on a variety of sensors. Available and emerging technologies offer a range of solutions for sensor systems but success in any particular application is often difficult to analyze. This makes the prediction of future trends more difficult. This paper looks back at some recent developments and forward to the next few years. In addition to the sensors required, some consideration is also given to control systems, which have increased dramatically in sophistication.