Motor drive with velocity noise filter

• US 20060267528A1
• Filed: 05/25/2005
• Published: 11/30/2006
• Est. Priority Date: 05/25/2005
• Status: Active Grant

• Current Assignee: Rockwell Automation Technologies Incorporated (Rockwell Automation, Inc.)
• Original Assignee: Rockwell Automation Technologies Incorporated (Rockwell Automation, Inc.)
• Inventors: Rehm, Thomas J.
• Granted Patent: US 7,187,142 B2
• Time in Patent Office: Days
• US Class Current: 318/432
• CPC Class Codes: B41F 13/0045 Electric driving devices
• CPC Class Codes: B41P 2213/734 each printing unit being driven by its own electric motor, i.e. electric shaft
• CPC Class Codes: G05B 19/414 Structure of the control system, e.g. common controller or multiprocessor systems, interface to servo, programmable interface controller
• CPC Class Codes: G05B 2219/41123 Correction inertia of servo
• CPC Class Codes: G05B 2219/41151 Finite impulse response filter
• CPC Class Codes: G05B 2219/41153 Infinite impulse response filter
• CPC Class Codes: G05B 2219/41423 Noise filter as function of rate of displacement, speed, for stabilisation
• CPC Class Codes: G05B 2219/45187 Printer
• CPC Class Codes: G05B 2219/50216 Synchronize speed and position of several axis, spindles

Abstract

A drive unit for controlling a motor includes a position feedback device and a velocity noise filter. The position feedback device is operable to generate a position signal relating to a position of the motor. The velocity noise filter is coupled to the position feedback device and operable to filter the position signal over a predetermined number of samples to generate a velocity feedback signal for the motor.

Claims

1. A drive unit for synchronizing operation of multiple motors, comprising:

at least one position feedback device operable to generate position signals relating to a position of each of at least two motors;

at least one finite impulse response filter coupled to the at least one position feedback device and operable to filter the position signals over a predetermined number of samples to generate velocity feedback signals for each of the at least two motors; and

a controller configured to receive the velocity feedback signals and substantially synchronize operation of the at least two motors based on the velocity feedback signals.

2. The drive unit of claim 1, further comprising:

at least one velocity regulator operable to generate a velocity error signal based on the velocity feedback signals and a reference velocity signal; and

at least one velocity error filter operable to filter the velocity error signal.

3. The drive unit of claim 2, wherein the controller is further configured to adjust a torque input signal applied to the at least two motors based on the velocity error signal.

4. The drive unit of claim 1, wherein the finite impulse response filter has a transfer function comprising:

5. The drive unit of claim 2, wherein the at least one velocity error filter comprises an infinite impulse response filter.

6. The drive unit of claim 5, wherein the infinite impulse response filter has a transfer function comprising:

7. The drive unit of claim 2, wherein the at least one finite impulse response filter has a first bandwidth, and the at least one velocity error filter has a second bandwidth, the second bandwidth being a multiple of the first bandwidth.

8. The drive unit of claim 7, wherein the multiple is between about 3 and about 9.

9. The drive unit of claim 1, further comprising at least one velocity regulator coupled to the at least one finite impulse response filter and operable to adjust a torque signal applied to each of the at least two motors based on the velocity feedback signal.

10. An electronic line system, comprising:

a signal generator operable to generate a reference velocity signal;

a virtual encoder operable to receive the reference velocity signal and generate a reference position signal based thereon;

a master drive unit operable to receive the reference velocity and reference position signals, comprising;

at least two motors;

a position feedback device operable to generate a feedback position signal relating to a position of the at least two motors;

a position regulator operable to compare the reference position signal to the feedback position signal to generate a position error signal;

a velocity noise filter coupled to the position feedback device and operable to filter the feedback position signal over a predetermined number of samples to generate a velocity feedback signal;

a velocity regulator operable to compare a sum of the reference velocity signal and the position error signal to the velocity feedback signal to generate a velocity error signal;

a motor control unit operable to adjust a torque input signal applied to a first of the at least two motors based on the velocity error signal; and

at least one slave drive unit operable to receive the reference velocity and reference position signals in a synchronous manner with respect to the master drive unit and control operation of a second of the at least two motors to be substantially synchronized with the first of the at least two motors.

11. The electronic line system of claim 10, wherein the at least one slave drive unit is configured to adjust a torque input signal applied to the second of the at least two motors to control operation of the second of the at least two motors to be substantially synchronized with the first of the at least two motors.

12. The electronic line system of claim 10, further comprising a velocity error filter operable to filter the velocity error signal.

13. The electronic line system of claim 10, wherein the velocity noise filter comprises a finite impulse response filter.

14. The electronic line system of claim 13, wherein the finite impulse response filter has a transfer function comprising:

15. The electronic line system of claim 12, wherein the velocity error filter comprises an infinite impulse response filter.

16. The electronic line system of claim 15, wherein the infinite impulse response filter has a transfer function comprising:

17. The electronic line system of claim 12, wherein the velocity noise filter has a first bandwidth, and the velocity error filter has a second bandwidth, the second bandwidth being a multiple of the first bandwidth.

18. The electronic line system of claim 17, wherein the multiple is between about 3 and about 9.

23. The electronic line system of claim 10, further comprising a plurality of line rollers arranged in a printing line and configured to be driven by the at least two motors.

19. A method for controlling operation of a plurality of motors to substantially synchronize the plurality of motors, comprising:

generating a position signal relating to a position of a first motor;

filtering the position signal over a predetermined number of samples using a finite impulse response filter to generate a velocity feedback signal for the first motor;

adjusting a torque signal applied to the first motor based on the velocity feedback signal; and

adjusting a torque input signal applied to a second motor to control operation of a second to be substantially synchronized with the first of the at least two motors.

20. The method of claim 19, further comprising:

generating a velocity error signal based on the velocity feedback signal and a reference velocity signal; and

filtering the velocity error signal.

21. The method of claim 20, wherein filtering the velocity error signal comprises filtering the velocity error signal using an infinite impulse response filter.

22. canceled