Research of discrete-time disturbance observer for linear motor

In order to reduce influence of thrust disturbance and non-linear friction on characteristics of linear motor, high speed/high accuracy position servo control system is implemented based on disturbance observer. This paper applies discrete time technique to design disturbance observer and compares performances of disturbance observer with time delay and without time delay. Simulation and experiment results demonstrate: in the high speed/high accuracy motion control of linear motor, small oscillation of velocity dynamical response can be eliminated and overshoot and steady time of position response can be reduced after applying disturbance observer with time delay.