Abstract
Background: The torsional vibration of the power transmission system has heavy effect on the ride comfort and safety of the vehicle, which has attracted plenty of research. Therefore, aiming at the torsional vibration problem of the electric vehicle power transmission system, enough study on how to suppress the torsional vibration is clearly of great benefit.
Objective: The goal of the work is to explore the new method to suppress the torsional vibration. The main contribution is that the parameter of the power transmission system is optimized and the adaptive fuzzy PID controller is proposed to be utilized and optimized to suppress the torsional vibration. Methods: An optimization objective function including the angular acceleration of the motor shaft, the decelerator and differential assembly and the half shaft is established as the output of the genetic algorithm fitness value. The error combination of the square root of the angular acceleration of the motor shaft, the decelerator and differential assembly and the half shaft is adopted as the input of the fuzzy inference controller and the PID controller, which can significantly simplify the fuzzy rule and the structure of the controllers. Results: The proposed method significantly reduces the torque amplitude of the motor shaft, the decelerator and differential assembly, the transmission half shaft, and the overall vibration amplitude. The maximum reduced vibration amplitude change is up to 41.22% and 87.04% respectively after parameter optimization and fuzzy PID control in the example. Conclusion: The comprehensive utilization of parameter optimization and adaptive fuzzy PID control can successfully suppress the torsional vibration phenomenon of the power transmission system, and the torsional amplitude of the angular velocity and angular acceleration decreases significantly. Therefore, the vehicle noise can be reduced and the stability can be improved. The study lays a foundation for solving the torsional vibration problem and the mechanical optimal design of the vehicle transmission system.Keywords: Power transmission system, torsional vibration, parameter optimization, genetic algorithm, fuzzy PID, electric. vehicle.