Motor control apparatus

Patent metadata

Field	Value
Publication number	US-10108182-B2
Application number	US-201615546692-A
Country	US
Kind code	B2
Filing date	Apr 22, 2016
Priority date	Apr 22, 2016
Publication date	Oct 23, 2018
Grant date	Oct 23, 2018

Abstract

A control unit includes a position command generation unit generating a position command, a position control unit outputting a first speed command such that detected position tracks the position command, a pressure command generation unit generating a pressure command, a pressure control unit outputting a second speed command such that detected pressure or force tracks the pressure command, a speed command selection unit selecting creep speed, the first speed command, or the second speed command and outputs it as a speed command for the motor to operate; and a speed control unit outputting a current command for supplying current to the motor such that the motor speed tracks the speed command output by the speed command selection unit. After selecting the first speed command, the speed command selection unit selects the second speed command or the creep speed at timing when the first speed command falls below the creep speed.

First claim

The invention claimed is:

1. A motor control apparatus that controls a motor that includes an encoder, the motor control apparatus comprising:
a position command generator to generate a position command that is a command value that causes a mechanical load driven by the motor to approach a subject to be pressurized and that causes a final position of the mechanical load to be before the subject to be pressurized at a certain distance from the subject to be pressurized;
a position controller to output a first speed command such that a position of the motor detected by the encoder tracks the position command;
a pressure command generator to generate a pressure command that is a command value of a pressure or a force to be applied to the subject to be pressurized;
a pressure controller to output a second speed command such that, when the mechanical load is pressed against the subject to be pressurized, a pressure or a force detected on the mechanical load tracks the pressure command;
a speed command selector to select one of a creep speed that specifies an upper limit of a speed of the motor to be used when the mechanical load comes into contact with the subject to be pressurized, the first speed command, and the second speed command and output the selected one of the creep speed, the first speed command, and the second speed command as a speed command for the motor to operate; and
a speed controller to output a current command for supplying a current to the motor such that the speed of the motor tracks the speed command output by the speed command selector, wherein
after the speed command selector selects the first speed command, the speed command selector selects one of the second speed command and the creep speed that has a smaller value at and after a timing when the first speed command falls below the creep speed.

2. The motor control apparatus according to claim 1 , wherein the position controller calculates a feedback speed command on a basis of a deviation between the position command and the position of the motor and outputs the feedback speed command as the first speed command.

3. The motor control apparatus according to claim 2 , wherein the speed command selector calculates the speed command by
selecting the first speed command as the speed command when starting is commenced and
selecting successively a smaller one of the second speed command and the creep speed at and after a timing when the first speed command that is output from the position controller falls below the creep speed during a deceleration action of position control in which an operation tracks the position command.

4. The motor control apparatus according to claim 2 , wherein the speed command selector calculates the speed command by
selecting the first speed command as the speed command when starting is commenced and
selecting successively a smaller one of the second speed command and the creep speed at and after a timing when a command speed that is a result of differentiation of the position command falls below the creep speed during a deceleration action of position control in which an operation tracks the position command.

5. The motor control apparatus according to claim 2 , wherein the speed command selector calculates the speed command by
selecting the first speed command as the speed command when starting is commenced and
selecting successively a smaller one of the second speed command and the creep speed at and after a timing when the feedback speed command falls below the creep speed during a deceleration action of position control in which an operation tracks the position command.

6. The motor control apparatus according to claim 1 , wherein the position controller adds, to a feedback speed command calculated on a basis of a deviation between the position command and the position of the motor, a feed-forward speed command calculated by a differentiation operation of the position command and outputs a result as the first speed command.

7. The motor control apparatus according to claim 6 , wherein the speed command selector calculates the speed command by
selecting the first speed command as the speed command when starting is commenced and
selecting successively a smaller one of the second speed command and the creep speed at and after a timing when the feed-forward speed command falls below the creep speed during a deceleration action of position control in which an operation tracks the position command.

8. The motor control apparatus according to claim 6 , wherein the speed command selector calculates the speed command by
selecting the first speed command as the speed command when starting is commenced and
selecting successively a smaller one of the second speed command and the creep speed at and after a timing when the first speed command that is output from the position controller falls below the creep speed during a deceleration action of position control in which an operation tracks the position command.

9. The motor control apparatus according to claim 6 , wherein the speed command selector calculates the speed command by
selecting the first speed command as the speed command when starting is commenced and
selecting successively a smaller one of the second speed command and the creep speed at and after a timing when a command speed that is a result of differentiation of the position command falls below the creep speed during a deceleration action of position control in which an operation tracks the position command.

10. The motor control apparatus according to claim 6 , wherein the speed command selector calculates the speed command by
selecting the first speed command as the speed command when starting is commenced and
selecting successively a smaller one of the second speed command and the creep speed at and after a timing when the feedback speed command falls below the creep speed during a deceleration action of position control in which an operation tracks the position command.

11. The motor control apparatus according to claim 1 , wherein, when the mechanical load is not in contact with the subject to be pressurized, the pressure controller stops an integral action to integrate a pressure deviation between the pressure command and the pressure or the force detected on the mechanical load.

12. The motor control apparatus according to claim 1 , wherein, when the speed command selector selects the creep speed or the second speed command, the position controller overwrites the position command with the position of the motor detected by the encoder.

13. The motor control apparatus according to claim 1 , wherein
the pressure controller comprises a phase compensator to perform phase delay compensation or phase advance compensation on a pressure deviation between the pressure command and the pressure or the force detected on the mechanical load, and
the pressure controller stops the phase delay compensation or the phase advance compensation in a case other than a case in which the second speed command is selected in the speed command selector.

14. A motor control apparatus that controls a moving speed of a mechanical load driven by a motor that includes an encoder, wherein
the moving speed of the mechanical load is controlled so as to agree with a first speed that causes a position of the motor detected by the encoder to track a position command, and,
at or after a timing when the first speed falls below a creep speed that specifies an upper limit of a speed of the motor to be used when the mechanical load comes into contact with a subject to be pressurized, the moving speed of the mechanical load is controlled so as to ag

Assignees

• Mitsubishi Electric Corp

Inventors

• Ueda Koichiro
• Matsuda Tatsuhiro

Classifications

• H02P29/20

  for controlling one motor used for different sequential operations · CPC title

• G05B19/416 Primary

  characterised by control of velocity, acceleration or deceleration (G05B19/19 takes precedence) · CPC title

• G05B2219/43001

  Speed, feed, infeed, acceleration, stopping problems · CPC title

• G05B2219/43006

  Acceleration, deceleration control · CPC title

• G05B2219/45033

  Wire bonding, wire wrap · CPC title