An antilock braking method based on sliding mode control (SMC) for electric vehicles (EVs) is proposed on the basis of antilock braking dynamics model, and hence an SMC controller of antilock braking system is designed. Aiming at the chattering of SMC, a method of parameter fuzzy optimization for exponential approach law is proposed, which can meet the requirements for small chattering, strong disturbance attenuation and fast convergence. In order to take full advantage of regenerative braking force, a method of braking force distribution between mechanical and electrical braking systems is elaborated. The simulations on the road with different friction coefficients show that the vehicle speed is in good agreement with the wheel speed during braking, and the slip ratio is kept within an optimal range. Adopting SMC based on fuzzy optimization, optimal slip ratio can be tracked fast and accurately. Furthermore, since the regenerative braking force is made full use of during braking, the energy recovery efficiency is high.
Global Sliding Mode Control for Nonlinear Vehicle Antilock Braking System
