Coupling Analysis of Control Parameters and Mechanical Parameters in Torsional Vibration of Electro-mechanical Transmission

Abstract

Due to the load fluctuation and engine complex excitation, the vehicle high-power electro-mechanical transmission system (EMT) is facing serious impact vibration problems. Reducing torsional vibration is one of the key paths to improve the reliability and comfort of the hybrid electro-mechanical transmission system. The system is accompanied by torsional vibration in the closed-loop operation. It is found that the torsional vibration response of the system is obviously affected by the coupling between the control parameters and the mechanical parameters. In order to reveal the mechanism of the coupling effect between the control parameters and the mechanical parameters of the system on the torsional vibration response of the system, a multi degree of freedom lumped parameter dynamic model of the hybrid electromechanical transmission system is established, and the inherent vibration characteristics of the system without the control force are analyzed. Then, the optimal steady-state torque control law, based on the Lyapunov stability principle and the state feedback method, is designed to achieve the coordinated torque distribution of multiple power ports in the transmission system. Based on the design of the control law, the vibration characteristics of the transmission system under the action of closed-loop control are simulated in MATLAB with the controller parameters as variables, and compared with the natural vibration characteristics of the open-loop system without control. The simulation results show that the control parameters of the torque control system of the electro-mechanical transmission system can change the position distribution of the poles of the system, thus significantly changing the vibration response characteristics of the system. The coupling relationship between the controller parameters and the mechanical parameters of the system is formed in the torsional vibration. Appropriate steady-state control methods and parameters is not only beneficial to improving the steady-state response of the system, but also to improving the NVH performance of the system.