Controlling stepper motor by virtual subsection method

A virtual subsection method is put forward aiming at the common problems in controlling of stepper motor.The method can not only be adaptable to complicated controlling environment,but also increase the controlling precision.Firstly,the stepping angel is divided averagely to N(determined by the precision requirement) fixed micro-steps,which is used as the basic unit.Then the controlling strategy is put forward,i.e.,controlling the motor according to both fixed period,variable step-length(worming)and variable period,fixed step-length(speediness).Secondly,according to the moving state of uniform acceleration,uniform speed and uniformly-retarded motion,the mathematic model is built with kinematics formula,the angle displacement and rotating speed in the present period are calculated out.The value of the next period is obtained according to the rotating speed,and changing phase or not is determined according to the present position.Consequently,the total process controlling is realized.Practical examples proved that the method is feasible in engineering and can obtain stepper parameters with satisfied precision.