Speed Control of Servo Drives with a Flexible Coupling Using a Modified Luenberger Observer

Elastic joints in 2-mass drive systems, may lead to torsional oscillation which is usually rectified by reducing the bandwidth of control system. In order to improve the control performance, feedback signals from all the states are required. All the states of a drive system with a flexible coupling cannot be easily measured so it is usually necessary to estimate some of the system states using appropriate observers. In this paper, the measurement noise and disturbances of the system are well rejected using a proposed modified Luenburger observer. Compared to the classic observers, a significant improvement in the quality of the state estimation of a two mass system is obtained at a wide range of reference speed. The proposed configuration is verified by simulation and experimental results in both open and closed loop configuration.