Modeling and Simulation of Electric and Hybrid Vehicles

Abstract

Compared to conventional vehicles, there are more electrical components used in electric, hybrid, and fuel cell vehicles, such as electric machines, power electronics, electronic continuously variable transmissions (CVTs), and embedded powertrain controllers [1, 2]. Advanced energy storage devices and energy converters, such as Li-ion batteries, ultracapacitors (UCs), and fuel cells are introduced in the next-generation powertrains. In addition to these electrification components or subsystems, conventional internal combustion engines (ICEs), mechanical systems, and hydraulic systems may still be present. The dynamic interactions among various components and the multidisciplinary nature make it difficult to analyze a newly designed hybrid electric vehicle (HEV). Each of the design parameters must be carefully chosen for better fuel economy, enhanced safety, exceptional drivability, and a competitive dynamic performance -all at a price acceptable to the consumer market. Prototyping and testing each design combination is cumbersome, expensive, and time consuming. Modeling and simulation are indispensable for concept evaluation, prototyping, and analysis of HEVs. This is particularly true when novel hybrid powertrain configurations and controllers are developed.Furthermore, the complexity of new powertrain designs and dependence on embedded software are a cause for concern among automotive research and development efforts. This results in increasing difficulty in predicting interactions among various vehicle components and systems. In such situations, a modeling environment that can model not only components but also embedded software, such as the electronic throttle controller (ETC) software, is needed. Effective diagnosis also presents a challenge. Modeling can play an important role in the diagnostics of the operating components. For example, running an embedded fuel cell model and comparing the actual fuel cell operating variables to those obtained from the model can help fault diagnosis of fuel cells. * © [2007] IEEE. Reprinted, with permission, from the Proceedings of the IEEE. Hybrid Electric Vehicles: Principles and Applications with Practical Perspectives, First Edition.