Winder motor control system

摘要

A system for controlling the speed-torque characteristic of a direct current motor which advantageously can be utilized to drive a surface wind machine for winding web material under controlled tension. The system generates a desired speed signal which is compared with a signal representing the actual motor speed to control a gating circuit and rectifier bridge for applying a selectively variable magnitude direct current voltage to the motor armature to cause the motor to run at the desired point on the speed-torque characteristic curve. The system generates a maximum no load speed adjustment signal which is compared with a speed adjustment signal to generate the desired speed signal. The motor armature current is sensed to generate a scaled armature current signal representing a decrease in the no load speed due to the load imposed on the motor. The system also generates a tension adjustment signal which defines a rate of decrease from the no load speed value to establish the speed-torque characteristic. The tension adjustment signal is compared with the scaled armature current signal to generate the speed adjustment signal thereby defining the slope of the speed-torque characteristic curve.