Abstract: Multi-wheel independent electric articulated bus both has mechanical characteristics of articulated vehicles and dynamic characteristics of distributed drive, aiming at the problems of folding, tailing and yaw which may occur during its limited conditions, and the yaw stability control research is carried out. A linear three-degree-of-freedom reference model is established, and the relevant state variables of the front compartment is estimated through particle filtering. The estimation results prove the validity of the model; the ideal response is obtained according to the three-degree-of-freedom reference model, and the idea of hierarchical control is adopted. The fuzzy equivalent switching sliding mode control is used in the upper layer. Joint control of yaw rate and articulation angle is adopted in the front compartment, and yaw rate control is adopted in the rear compartment, by which the additional yaw moment required is obtained; the lower layer adopts the quadratic programming method to optimize the torque distribution with the tire utilization rate as the optimization target. The simulation analysis of the steering angle step condition and the double lane change condition is carried out on the dSPACE-ASM platform. The results show that the control strategy can effectively improve the yaw stability of the vehicle under various working conditions. Compared with the equal torque distribution, the tire utilization rate is effectively reduced, and the control effect is more significant.

Key words: in-wheel drive, articulated bus, fuzzy equivalent control, yaw stability, torque distribution