Torque Distribution Algorithm for an Independently Driven Electric Vehicle Using a Fuzzy Control Method

Abstract

Abstract:The in-wheel electric vehicle is expected to be a popular next-generation vehicle because an in-wheel system can simplify the powertrain and improve driving performance. In addition, it also has an advantage in that it maximizes driving efficiency through independent torque control considering the motor efficiency. However, there is an instability problem if only the driving torque is controlled in consideration of only the motor efficiency. In this paper, integrated torque distribution strategies are proposed to overcome these problems. The control algorithm consists of various strategies for optimizing driving efficiency, satisfying driver demands, and considering tire slip and vehicle cornering. Fuzzy logic is used to determine the appropriate timing of intervention for each distribution strategy. A performance simulator for in-wheel electric vehicles was developed by using MATLAB/Simulink and CarSim to validate the control strategies. From simulation results under complex driving conditions, the proposed algorithm was verified to improve both the driving stability and fuel economy of the in-wheel vehicle.

ABS braking on rough terrain

“…: Tyre contact friction generation mechanism (Gillespie, 1992) (Park et al, 2015) ..... 3 Figure 5: Pneumatic trail of a tyre (Gillespie, 1992) (Rover Group Limited, 1996) .................. 5…”

“…The wheels lock-up completely at 100% slip, as the wheels are essentially not rotating while the vehicle is still moving. Figure 4: Different friction coefficients for different terrain conditions (Park et al, 2015) 1.1.5. Lateral force and lateral slip When a vehicle is steered while cornering, lateral force is generated normal to the direction of travel of the wheel.…”

Torque Distribution Algorithm for an Independently Driven Electric Vehicle Using a Fuzzy Control Method: Driving Stability and Efficiency

“…Generating same driving torque on four wheels makes it difficult to drive the motor in the efficient region. As a solution to this problem, a driving torque distribution strategy that appropriately distributes the driving force and regenerative braking force of the front and rear wheels according to the situation to improve the efficiency of the vehicle was proposed as described in previous paper [24]. However, since the developed distribution strategy is a strategy that considers driving efficiency in a stable situation, there is a problem of reducing driving stability of the vehicle in a rapid cornering situation or low-friction road situation.…”

Co-Design Based Lateral Motion Control of All-Wheel-Independent-Drive Electric Vehicles with Network Congestion

“…Meanwhile, there are also great demands for vehicle drivability [2] and driving safety [3]. With the rapid development of driving motor technologies, the all-wheel-independent-drive electric vehicle (AWID-EV), as an emerging configuration of EVs, has attracted increasing research efforts [4][5][6][7][8][9][10][11][12][13]. With driving motors, each wheel of the AWID-EV can individually generate not only driving torque but also braking torque, which greatly increases the flexibility and possibility of fully utilizing the adhesion of each tire and the efficiency of each motor.…”

“…With driving motors, each wheel of the AWID-EV can individually generate not only driving torque but also braking torque, which greatly increases the flexibility and possibility of fully utilizing the adhesion of each tire and the efficiency of each motor. Therefore, the AWID-EV has considerable advantages in terms of energy optimization, drivability and driving safety [6,14,15]. congestion problem in the lateral motion control of AWID-EVs has not been addressed in the literature by other researchers.…”