Acceleration Estimation and Feedback for Two-Mass Servo Systems

Servo drives comprise a high dynamic and smooth motion control which is typically based on a cascaded control structure with position measurement or estimation. By including an additional acceleration feedback, the command and disturbance behavior can be improved significantly. Based on the proven cascaded control structure, this contribution analyzes an extended control concept with additional acceleration feedback for elastic mechanical systems with high stiffness. In order to reduce the measurement effort, a Kalman filter is used to estimate the acceleration. Based on an experimentally identified two-mass model of the system, the proposed concept is compared with the proven cascaded control by simulations and experimental results. For the experimental validation, a stiff mechanical system coupling two electrical synchronous motors, for the intended driving and emulated loading is utilized.