Electric and Hybrid Vehicles: Technologies, Modeling and Control - A Mechatronic Approach

9Control of Electric and Hybrid Electric Vehicle Dynamics

9.1 Introduction

Vehicles are normally controlled by driver commands that are applied to the vehicle through the use of the steering wheel, as well as through the brake and accelerator pedals. Vehicles consistently respond to these driver commands during normal driving conditions; however, under harsher conditions such as slippery roads or during severe maneuvers, vehicles may not adequately respond to these driver commands. In such situations, controlling the vehicle becomes a difficult task for the driver, and may even result in the driver completely losing control of the vehicle. In other words, during harsh driving conditions, vehicle dynamics is mostly nonlinear, and control of the vehicle through driver input is not easy. In such situations, the vehicle should be stabilized and controlled through methods other than traditional driver inputs.

An active control system can be used to control vehicle dynamic behavior during harsh driving conditions. Technically, such systems are categorized as vehicle dynamic control (VDC) systems. The early attempts to develop VDC systems date back to early 1980s. Since then, both auto-makers and academics have conducted extensive research in this field, resulting in the implementation of commercial systems such as the anti-lock braking system (ABS), the traction control system (TCS), and the electronic stability program (ESP) in mass-produced cars.

In parallel with the idea of developing ...