Slip Suppression Control for Electric Vehicle Using Bias Torque Function Control

We propose a new bias torque function control (B-TFC) method for electric vehicles (EVs) for starting on uphill roads and confirm its effectiveness by simulations and experiments. In the simulation, we developed a new model for accurate behavior of the evaluation system. We compared three kinds of slip suppression control methods, namely without TFC, with TFC (conventional), and the B-TFC. In the case of the B-TFC method, an EV carrying one person can start moving on a 1° wet uphill road without rolling backward. In the simulation using the developed model, the torque is suppressed and fluctuates between the command and bias torques. Then, the vehicle speed at 3s is 1.7m/s, which is the highest among the compared methods. The experimental results therefore agree with the simulations and the developed simulation model reproduces the experimental trends with high accuracy. We confirm that the proposed B-TFC method improves acceleration and slip suppression performances.