Electric motor control device

摘要

An electric motor control device for performing tandem control for driving one movable component includes, for each electric motor, a position controller, a speed controller, and a current controller. Further, each electric motor also has a preload controller for adding a preload torque to a torque command Tm calculated by the speed controller, and to a torque command Ts calculated by the speed controller. The preload controller calculates a minimum necessary preload torque for eliminating backlash in accordance with a position of the movable component.

主权项

1. An electric motor control device for performing tandem control for driving a movable component for which an amount of load caused by gravity varies in accordance with a position of the movable component, using a main electric motor and an auxiliary electric motor, the electric motor control device comprising, for each of the electric motors:
a position controller configured to calculate a speed command for a corresponding electric motor based on a common position command and to control the position of a movable component for which an amount of load caused by gravity varies in accordance with a position of the movable component; a speed controller configured to calculate a torque command for the corresponding electric motor based on the speed command calculated by the position controller; a preload controller configured to apply a preload torque to the torque command calculated by the speed controller, the preload torque having opposite polarities for the main electric motor and the auxiliary electric motor; and a current controller configured to calculate a current command for the corresponding electric motor based on the torque command, wherein the preload controller is configured to vary the preload torque based on the position of the movable component.