David Germann

Toward a Systematic Design for Turbocharged Engine Control

The efficient development of high performance control is becoming more important and more challenging with ever tightening emissions legislation and increasingly complex engines. Many traditional industrial control design techniques have difficulty in addressing multivariable interactions among subsystems and are becoming a bottleneck in terms of development time. In this article we explore the requirements imposed on control design from a variety of sources: the physics of the engine, the embedded software limitations, the existing software hierarchy, and standard industrial control development processes. Decisions regarding the introduction of any new control paradigm must consider balancing this diverse set of requirements. In this context we then provide an overview of our work in developing a systematic approach to the design of optimal multivariable control for air handling in turbocharged engines.

Identification Techniques for Control Oriented Models of Internal Combustion Engines

The use of mathematical models is widespread in the design process of modern internal combustion engines. A driving factor for this trend is the rising complexity of engine systems due to tightening emission limits and increasing demands on fuel efficiency. This chapter focuses on control oriented models for turbocharged diesel engines which were specifically developed for use in an advanced model based control design process. A number of challenges had to be overcome to guarantee stability of these models both in simulation and during identification. The solutions for these issues are presented in this chapter together with an innovative identification approach which performs the calibration of the overall engine model on top of the previously executed identification of individual engine components. Example modeling results are included for a six cylinder commercial diesel engine with EGR and dual stage turbocharging.

Experimental Results for Sensor Selection and Multivariable Controller Design for a Heavy-Duty Diesel Engine

Abstract In this paper we consider the issues facing the design of a practical multivariable controller for a heavy duty engine equipped with an exhaust gas recirculation (EGR) valve and variable geometry turbocharger (VGT). Issues facing the selection of sensors are considered, and a combination of physical as well as practical implementation requirements are treated in the choice and design of a model predictive controller. The nonlinearities and the multivariable nature of the system are investigated in order to coordinate both actuators such that the the emission and torque response requirements of the system are met. The process of modeling the engine, development of the controller, the hardware set-up that was utilized in running the controller validation work and, the results of utilizing the proposed system over transient cycles (e.g., FTP) and other certification cycles (e.g., RMCSET cycle) are presented.