Stepper Motor Angular Velocity Detection Circuit
Original Publication Date: 1989-Nov-01
Included in the Prior Art Database: 2005-Jan-29
This article describes a circuit and method of connection that senses the back EMF of a permanent magnet (PM) stepper motor to detect the angular velocity of the motor shaft. This is done when the motor's chopped current driver is off and the motor is being driven as a generator. Velocity detection is achieved using a voltage threshold detection circuit connected directly across the motor windings.