Introduction to Hybrid Vehicle System Modeling and Control

Chapter 7: Other Hybrid Vehicle Control Problems

7.1 Basics of internal combustion engine control

The primary function of engine control is to adjust the engine torque generated to meet the required torque from the driver and at same time to satisfy the requirements of emission, fuel economy, driving comfort, and safety. For a spark ignition (SI) engine, the torque is generated through a combustion process and determined by the air mass, fuel mass, and ignition time, as shown in Fig. 7.1. For a diesel engine, the torque is also generated by a combustion process, but it is a function of the injected fuel mass and injection time, as shown in Fig. 7.2. In order to achieve the objectives, all variables that influence the torque are controlled by the electronic/engine control unit (ECU). This section will briefly describe the general schematic diagrams of SI engine and diesel engine control. The detailed engine controls are very sophisticated, and they are beyond the scope of this book. The interested reader is refer to the literature for further studies (Guzzella and Onder, 2010).

Figure 7.1 Torque generation process of SI engine.

Figure 7.2 Torque generation process of diesel engine.

SI Engine Control The SI engine control system is complex and consists of many subsystems. From a ...