Adaptive control of hybrid electric vehicle

• Main Author: Khah, Dennis Kok Hong.
• Other Authors: Wen Changyun
• Format: Final Year Project
• Language: English
• Published: 2013
• Subjects: DRNTU::Engineering
• Online Access: http://hdl.handle.net/10356/53169
• Institution: Nanyang Technological University

Hybrid Electric Vehicles (HEV) has received considerable attention in the world today for its improvements in fuel economy compared to gasoline powered vehicles and reduced carbon emissions to the environment. As much as the research done on the energy management of the Hybrid Electric Vehicle, the control strategy research that provides driving comfort during lane change and sharp manoeuvres contributes significantly to the success of these vehicles. Driving comfort becomes a significant area of consideration especially with rapidly changing road conditions and external disturbances like road slips and rocky roads which could lead to undesirable yaw disturbances. These yaw disturbances increase vehicle handling effort and compromise the stability of the vehicle. In most cases, manual control actions by the driver are not swift enough to perform the necessary action for stabilizing the yaw disturbances. In order to resume the stability of the vehicle, an automatic control system which can act faster and more accurately under such circumstances is essential. Hence, this project involves the analysis of various control strategies in improving the directional response of a Hybrid Electric Vehicle through yaw rate control. Firstly, preliminary studies based on an assigned research paper is performed to familiarise with the modelling of the HEV plant using a linear bicycle model, factors involved with yaw rate control and the desired output to be obtained. The operating principles of the neural adaptive controller based on model reference adaptive control (MRAC) used in the research paper for yaw rate control was also analysed. Query on the linear HEV bicycle model in the research paper is also presented. Lastly, various control schemes such as the IMC control scheme, empirical PID control scheme and the adaptive control scheme (MRAC) were implemented on a separately derived linear bicycle model, to compare the advantages, disadvantages and to determine which control scheme is suitable for maintaining vehicle stability during actual vehicle operation. The robustness of the controller was further tested with another plant model of similar structure but with different poles and zeros to represent the variation of system parameters during vehicle operation.