Hybrid non-singular terminal sliding-mode controller design for an electric vehicle system with a brushless d.c. motor

The present paper proposes an efficient and robust control scheme for an electric vehicle (EV) with a brushless d.c. motor. First, after analysing the control principle for the brushless d.c. motor, the equivalent circuits of the control system are depicted and the mathematical models under normal driving and energy regeneration are derived, respectively. Then, by combining the merits and defects of the non-singular terminal sliding-mode (NTSM) with the high-order sliding-mode (HOSM) method, a hybrid non-singular terminal sliding-mode control scheme (HTSM) for robust control of the EV is put forward to guarantee both system performance and robust stability. The experimental results show that the scheme exhibits better performance and higher efficiency than the traditional proportional-integral-derivative (PID) controller. Furthermore, more energy is recovered and the proposed scheme improves the driving range by 5.7 per cent more than the PID controller.