Control of Stepper Motor Stop Phase
Original Publication Date: 1981-Jun-01
Included in the Prior Art Database: 2005-Feb-11
For a dead stop from any speed and at any inertial load and friction, microprocessor controller and control algorithm are described. The controller and the algorithm measure the velocity or count clock cycles within a spatial distance. In addition, they select one out of several predetermined control paths, switching motor field phases forward or backward, depending on the data measured, and at predetermined rotor positions. For the last fractions of a step, in which the motor comes to rest, the control switches from angular to time control.