Suppression of Load Oscillations in Precision Servomechanisms Sensing Only Motor Position

An analysis of the two-mass model of a servomechanism is first presented in this paper. The analysis stands as a basis for the design of a P/PI controller where suppression of load oscillations, rather than fast setpoint tracking of the motor position is pursued. Further improvements of the load behavior can be achieved by a notch filter placed outside the velocity loop. Simulation results are given to assess the effectiveness of the proposed approach.