A model-based flexural rotor vibration control in cage induction electrical machines by a built-in force actuator

Abstract

In this paper active control of flexural rotor vibration in electrical machines is examined. We consider attenuation of discrete low-frequency range forced vibration components by means of an adaptive harmonic control strategy. A built-in force actuator for actively generating force on the machine rotor is investigated. Previously, such an actuator has mainly been used in bearingless machine design for rotor levitation. The action of the actuator is based on electromechanical interaction between the rotor and the stator of the machine. A low-order linear parametric state-space model is derived for the actuator–rotor system. Parameter estimation is carried out using simulation data obtained from a detailed two-dimensional time-stepping finite element field-circuit model of the machine. Hence, model-based control design is performed using the identified model. The controller is verified by embedding it into the finite element analysis. As a result we present a virtual plant of the machine with vibration control. The virtual plant is introduced as a means of vibration control design prior to implementing the control algorithms in a real machine. Simulation results using real machine data and finite element time-stepping method are presented.