Dejun Yin

A Novel Traction Control for EV Based on Maximum Transmissible Torque Estimation

Controlling an immeasurable state with an indirect control input is a difficult problem faced in traction control of vehicles. Research on motion control of electric vehicles (EVs) has progressed considerably, but traction control has not been so sophisticated and practical because of this difficulty. Therefore, this paper takes advantage of the features of driving motors to estimate the maximum transmissible torque output in real time based on a purely kinematic relationship. An innovative controller that follows the estimated value directly and constrains the torque reference for slip prevention is then proposed. By analysis and comparison with prior control methods, the resulting control design approach is shown to be more effective and more practical, both in simulation and on an experimental EV.

Electric Vehicle Traction Control: A New MTTE Methodology

In motion control of electric vehicles (EVs), the undetectable road conditions and varying vehicle parameters challenge the steering ability and validity. This article investigates a new traction control (TC) approach that uses the maximum transmissible torque estimation (MTTE) scheme to carry out the antislip control of EVs. A closed-loop disturbance observer is employed to enhance the steering stability and to improve the robustness on perturbation in wheel inertia of the MTTE approach. This proposed scheme, which contains the closed-loop friction torque estimator, does not require the use of any differentiator. Additionally, the inversion of the controlled plant is unnecessary. The real experiment demonstrated the effectiveness and feasibility of the presented antislip strategy.

Traction Control for EV Based on Maximum Transmissible Torque Estimation

Research on motion control of EVs has progressed considerably, but traction control has not been so sophisticated and practical because the velocity of vehicles and the friction force are immeasurable. This work takes advantage of the features of driving motors to estimate the maximum transmissible torque output in real time based on a purely kinematic relationship, and then proposes an innovative controller to follow the estimated value directly and constrain the torque reference for slip prevention. By comparison with prior control methods, the resulting control design approach is shown to be more effective and robust both in simulation and on an experimental EV.

A new approach to traction control of EV based on maximum effective torque estimation

This paper presents a new control algorithm that prevents wheel skidding of electric vehicles in the presence of uncertainties in tire-road conditions. An estimator of the maximum effective torque is realized by wheel velocity and input torque, which is based on a purely kinematic relationship between the wheel and the chassis. In order to enhance the stability of the control system and preserve handling performance for the driver, a half-closed loop controller makes use of the estimated result to restrain the maximum torque output to the wheels. Simulation and experimental results indicate that this is an effective and practical approach to prevent slip.

A Novel Traction Control for Electric Vehicle without Chassis Velocity

Due to the growing concern about global environmental problems and shrinking nonrenewable energy sources, research on electric vehicles and hybrid electric vehicles is once again attracting significant attention. Meanwhile, significant improvements in power electronics, energy storage and control technology have made electric vehicles fully feasible, preparing the state of the art for their return to the market (Chau et al., 2008; Affanni et al., 2005; Nagai, 2007). Beside the advantages for the environment, manufacture and maintenance, from the viewpoint of control technology, the most distinct advantages of electric vehicles have not been well recognized. Since electric vehicles and some specially configured hybrid electric vehicles are driven by electric motors, the advantages provided to these electric vehicles can be summarized as follows (Hori, 2004): 1. Quick torque generation 2. Easy torque measurement 3. Possibility of independently equipped motors for each wheel On the other hand, considering the different regions of the world, the increase of the mobility shows a clear correlation to the gross domestic product. With further economic growth, we can predict an even greater increase in mobility and in traffic density throughout the world. For this reason, vehicle motion control systems have been developed to provide active safety control, and have made significant technological progress over the last decade to enhance vehicle stability and handling performance in critical dynamic situations by introducing computer control technology. From the development history of vehicle motion control, it can also be found that, effective operation of any vehicle control system is based on some basic assumptions, for example, the output torque being able to accurately work on the vehicle. For this purpose, traction control, as the most primary active safety control for vehicles, is developed to ensure the effectiveness of the torque output. The key to traction control is antislip control, when the vehicle is driven or brakes on a slippery road, especially for light vehicles because they are more inclined to skid on slippery roads. Traction control must not only guarantee the effectiveness of the torque output to maintain vehicle stability, but also provide some information about tire-road conditions to other vehicle control systems. Moreover, in electric vehicles a well-managed traction control system can cover the functions of ABS, because

A novel traction control of EV based on maximum effective torque estimation

Controlling an immeasurable state with an indirect control input is a difficult problem faced in traction control of a vehicle. Research on motion control of electric vehicles has progressed considerably, but anti-slip control has not been so sophisticated and practical because of this difficulty. Therefore, this work takes advantage of the features of motors to estimate the maximum friction force from road in real time based on a pure kinematic relationship between the wheel and the chassis. Then, a half-closed loop controller makes use of the estimated value to limit the maximum torque output to the wheel. The resulting control design approach is shown to be effective and practical on an experimental electric vehicle as well as through simulations.

A new MTTE methodology for electric vehicle traction control

A new traction control which utilizes the maximum transmissible torque estimation (MTTE) scheme to execute the anti-slip control of electric vehicles is proposed in this study. Since the function of embedded knowledge mechanism, the chassis velocity and information about tire-road conditions is unnecessary. A closed-loop observer with disturbance estimation performance is employed to enhance the steering stability of MTTE approach. The proposed scheme which contains the closedloop friction torque estimator is not required to fulfill any differentiator. Moreover, the inversion of the controlled plant is also unnecessary. Evaluation examples are given to illustrate the performance and feasibility of the presented anti-slip strategy.

Electric Vehicle Traction Control - A New MTTE Approach with PI Observer

Abstract This paper investigates a new traction control approach which utilizes the maximum transmissible torque estimation (MTTE) scheme to carry out the anti-slip control of electric vehicles. An innovative scheme for slip prevention, which requires neither chassis velocity nor information about tire-road conditions, is then proposed. A PI type disturbance observer is employed to enhance the steering stability of MTTE approach. The proposed scheme which contains the closed-loop friction torque estimator is not required to utilize any differentiator. Additionally, the inversion of the controlled plant is unnecessary. Illustrated examples are given for evaluating the performance and feasibility of the presented anti-slip strategy.