STABILITY ANALYSIS AND SUPPRESSION CONTROL OF ROTOR OSCILLATION FOR STEPPING MOTORS BY LYAPUNOVS DIRECT METHOD

Stepping motors are used as the driver for positioning in control syst ems, It is well-known that the transient response of a stepping motor is generally oscillatory in the case of open-loop control, The rotor o scillation must be suppressed in quick positioning applications, In th is paper, the stability analysis and the suppression control of rotor oscillations of variable reluctance stepping motors are studied by Lya punov's direct method. Since the motor is a nonlinear system, the meth od is useful to analyze the stability of the motor, The suppression co ntrol of rotor oscillations is achieved by excitation control of phase windings using Lyapunov function, The validity of this method is exam ined by experiments.