Scheduled System Maintenance:
On Monday, April 27th, IEEE Xplore will undergo scheduled maintenance from 1:00 PM - 3:00 PM ET (17:00 - 19:00 UTC). No interruption in service is anticipated.
By Topic

Optimal and Fault-Tolerant Torque Control of Servo Motors Subject to Voltage and Current Limits

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

1 Author(s)
Aghili, F. ; Canadian Space Agency, Saint-Hubert, QC, Canada

This brief presents an optimal and ripple-free torque control of a brushless servo motor with any back-emk waveform that minimizes power dissipation subject to voltage and current limits of the motor's drivers/amplifiers. When one or more phases reach the voltage and/or current limits, the controller optimally reshapes the stator currents of the remaining phases for continuing accurate torque production. This allows the motor to operate above the rated speed and torque that would be achieved without current reshaping. In the event that an open-circuit or short-circuit of a winding occurs, the torque controller can also isolate the faulty phase in order to generate torque as requested given the voltage and current constraints of the healthy phases. Assuming the inductance of stator coils is negligible allows the description of the phase voltage and current limit requirements by a set of inequity constraints. It follows by the derivation of a closed-form solution for the optimal phase currents at given angular position, velocity, and desired torque-rendering the control algorithm suitable for real-time implementation. Experimental results illustrate the capability of the controller to achieve precise torque production during voltage/current saturation of the motor's drivers or a phase failure.

Published in:

Control Systems Technology, IEEE Transactions on  (Volume:21 ,  Issue: 4 )