Yaw Stability Research of the Distributed Drive Electric Bus by Adaptive Nonsingular Fast Terminal Sliding Mode Control

Abstract

Due to the high center of gravity of distributed drive electric buses, it is crucial to enhance their stability and sliding mode control (SMC) is an effective method to enhance vehicle yaw stability. However, the traditional SMC needs to know the upper limits of the interference term in advance and select a better switching gain to obtain a better control effect, which is impossible for vehicle control. To solve the existing problems, an improved adaptive nonsingular fast terminal sliding mode (ANFTSM) control is presented to enhance the stability of distributed drive electric bus. An uncertainty term is introduced as a switching term in the sliding mode variable and the switching gain in the controller is obtained by parameter adaptation without knowing any uncertainty information. In addition, to enhance the stability of the vehicle in real-time, an adaptive neuro fuzzy inference system (ANFIS) for the weighting factor in the sliding surface is adjusted. A co-simulation of Matlab/Simulink–TruckSim is performed to verify the effectiveness of the algorithm under two typical conditions. The results indicate that the proposed control can follow the ideal value better which improves handling stability and chattering is weaker. Furthermore, the proposed control requires fewer control actions, and also reduces the motor torque variation.