Motor drive with velocity noise filter

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.

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;
• 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;
• at least one velocity regulator operable to generate a velocity error signal based on the velocity feedback signals and a reference velocity signal;
• at least one velocity error filter operable to filter the velocity error signal;
• wherein the at least one velocity error filter comprises an infinite impulse response filter;
• wherein the infinite impulse response filter has a transfer function comprising:
• G
• ⁡
• (
• s
• )
• =
• 1
• (
• 1
• +
• T
• f
• ⁢
• s
• )
• 2
• ,
• where Tf equals a filter time constant.