Hybrid Stepping Motor Servo System Based On DSP

The stepping motor is a popular type of motors in industrial control. It has the capability to conduct precise open-loop control without speed or position sensors, thus has been widely applied in office and factory automation applications. The hybrid stepping motor, the control object in this project, integrates the advantages of Permanent magnet stepper motor and Reaction Stepper Motor,and performs well with high precision and efficiency. However, the traditional open-loop control based stepping motors vibrate easily, generate a lot of noise, and even losing steps.Practice experience demonstrates that subdivision driving technology could efficiently increase the stability of stepping motors, and decrease both voices and vibrates as well. Since the working schemas of the three-phase hybrid stepping motor and the synchronous inductor motor are similar, the control of hybrid stepping motors could refer to the control methods for synchronous inductor motors. This research applies the FOC of synchronous inductor motors into the hybrid stepping motor control system and digitalized fulfills the subdivision control step angle of stepping motors.This article first analyzes the working schema and principles of the three-phase hybridstepping motor. Under the assumption of ignoring a number of nonlinear factors, we then propose an ideal mathematical model of the three-phase hybrid stepping motor and design corresponding control methods based on the model. Finally we build the hardware and software systems of a three-phase hybrid stepping motor driver using DSP TMS28030 as the core of controller. Experiments of the system produce satisfactory circuit waves, indicating the validity of the proposed control methods.