Study On Subdivision Driving Technique Of Stepper Motor

Stepper motor is a kind of electromechanical component that is driven in step angle or line displacement by electric pulse signal. Because of having the advantage of easy open-loop control and no accumulating error, stepper motor is being applied widely in many fields. In order to meet the requirement of high-precision orientation and moving smoothness, subdivision driving of stepper motor is adopted.In this paper, the working principle and magnetic network of two-phase hybrid stepper motor are introduced, and the dynamic equation is deduced. The PWM subdivision driving based on single-chip processing unit control using electric current vector even rotation with uniform amplitude method is presented, after analyzing two methods of subdivision driving: equal electric current and electric current vector even rotation with uniform amplitude, realizing 32 subdivision driving of stepper motor. For compensating the nonlinear error between winding current and the result magnetic field of stepper motor, the method of minimum square is adopted to fit and correct the error curve of subdivision step angle, and the subdivision precision is improved. The autoaligment instrument and accuracy turntable with digital display are used to detect the step angle after 32 subdivision, and the experiment results are given, the mean-square error of step angle after 32 subdivision is less than 3.7%.