JP-2026075542-A - Vibration control system for electric vehicles

Abstract

[Problem] To provide a vibration control device for an electric vehicle that suppresses vibrations generated in a moving vehicle due to fluctuations in the number of drives transmitted by the rotation of the propeller shaft. [Solution] The vibration control unit 29 of the electronic control device (vibration control device) 30 calculates a vibration damping rotational speed Npr or vibration damping torque Tpr that pulsates with the opposite phase and amount to the rotational fluctuations of the propeller shaft 24. A vibration damping current signal that generates this vibration damping rotational speed Npr or vibration damping torque Tpr is superimposed on the drive current of the second electric motor MG2, thereby canceling out vibrations originating from the rotational fluctuations of the propeller shaft 24 and suppressing vibrations of the vehicle while it is running that originate from the rotational fluctuations of the propeller shaft 24. [Selection Diagram] Figure 1

Inventors

• 今井 信治

Assignees

• トヨタ自動車株式会社

Dates

Publication Date

20260508

Application Date

20241022

Claims (1)

1. A vibration control device for an electric vehicle, wherein a propeller shaft having universal joints at both ends is connected between a drive unit consisting of an engine and/or a first electric motor and a differential gear system having a second electric motor that distributes the driving force of the drive unit and/or the second electric motor to the left and right drive wheels, A rotational fluctuation detection unit for detecting rotational fluctuations of the propeller shaft, A vibration damping torque calculation unit calculates a vibration damping rotation speed or vibration damping torque that pulsates in opposite phase to the rotational fluctuations of the propeller shaft, A vibration control device for an electric vehicle, characterized by including a vibration control unit that cancels out vibrations originating from rotational fluctuations of the propeller shaft by superimposing a vibration-damping current signal that generates a vibration-damping rotation speed or vibration-damping torque calculated by the vibration-damping torque calculation unit onto the drive current of the second electric motor.

Description

This invention relates to a vibration control device for an electric vehicle having a propeller shaft connected via a universal joint in its power transmission system, which controls torque vibrations originating from the intersection angle of the universal joint. Patent Document 1 discloses an electric vehicle equipped with an electric motor capable of applying vibration damping torque to the drive shaft in order to suppress rotational fluctuations of the crankshaft caused by the in-cylinder pressure torque and the inertial torque of the reciprocating mass generated by engine combustion. The invention discloses setting the vibration damping torque so that it is minimized at the timing when the pulsation of the in-cylinder pressure torque is at its maximum. Japanese Patent Publication No. 2023-157125 The diagrams illustrate the schematic configurations of the drive systems of electric vehicles to which the present invention is applied, wherein the vehicle in (a) comprises a drive unit consisting of an engine or a first electric motor and a transmission, a differential gear device having a second electric motor on the input shaft side of the differential mechanism, and a propeller shaft connecting the drive unit and the differential gear device via a universal joint; the vehicle in (b) comprises a drive unit having a power distribution mechanism having a first rotating element connected to the engine, a second rotating element and a third rotating element connected to the first electric motor, a differential gear device having a second electric motor on the input shaft side of the differential gear mechanism, and a propeller shaft connecting the drive unit and the differential gear device via a universal joint; and the vehicle in (c) has a differential gear device having a second electric motor on the side gear side of the differential gear mechanism.Figure 1 is a flowchart illustrating the key aspects of the operation of the vibration control device for the electric vehicle.Figure 2 is a flowchart illustrating the key components of another operational example of the vibration control device for the electric vehicle.This is a flowchart illustrating the main parts of another operational example of the vibration control device for the electric vehicle shown in Figure 1 or Figure 2. The embodiments of the present invention will be described in detail below with reference to the drawings.