Development of Speed Sensorless Control System for Multimotor Drive in Steel Plant

Abstract

In industrial plants such as those for iron and steel process, paper machine process and others, multimotor drive system are very popular. Speed sensorless vector control is most suitable for those system with high performance, high reliability, low cost and less maintenance. Very few papers about multimotor drive system, however, have been reported. This paper describes such a drive system.
In case of unbalanced load among the motors, the phase differences between their vectors cause insufficient performance, especially during regenerating at low speed. In this paper, we propose an advanced sensorless control for multimotor drives. The proposed control system estimates the axis of the motors with heavy load and follows it.
The proposed drive system are now operating with good performance in steel and other plants.