An Active Magnetic Bearing for Thin-Walled Rotors: Vibrational Dynamics and Stabilizing Control

Linearizing Control of a Distributed Actuation Magnetic Bearing for Thin-Walled Rotor Systems

“…where N 0 is the maximum number of coil-turns, as detail in Table 3. This scheme creates a sinusoidal variation in actuator forces around the circumference of the rotor, thereby helping to minimize flexural distortion and vibration of the rotor wall [5].…”

“…Feedback control of actuator coil currents based on measured rotor displacements is used to stabilize the rotor positioning within the bearing and prevent excessive vibration [1,2]. Although AMBs have been widely applied with solid-shaft rotors, there has been recent research interest in the design and application of AMBs with hollow and ring-like rotors [3][4][5][6]. In the case of thin-walled rotors, a larger number of smaller actuators may be incorporated within the bearing to support the rotor around its periphery [5].…”

“…Although AMBs have been widely applied with solid-shaft rotors, there has been recent research interest in the design and application of AMBs with hollow and ring-like rotors [3][4][5][6]. In the case of thin-walled rotors, a larger number of smaller actuators may be incorporated within the bearing to support the rotor around its periphery [5]. However, this results in a more complex relation between the forces acting on the rotor and the currents within the actuator coils, which brings challenges in achieving exact or approximate linearization of the bearing force behavior within a control algorithm.…”

“…This paper considers the feedback linearization problem for a novel design of radial magnetic bearing with distributed actuation topology. The distributed actuation magnetic bearing (DAMB) incorporates a multiplicity of small electromagnetic actuators in an arrangement that is suited to supporting hollow lightweight and thin-walled rotors [5]. A distinguishing feature is that both the x and y force components couple with all four of the supplied coil currents, and hence the linearization problem cannot be separated into x and y axis subsystems.…”

Decoupling control of magnetically suspended motor rotor with heavy self-weight and great moment of inertia based on internal model control

“…The magnetically suspended rotational machine has been widely applied in high-speed motors (Li et al, 2020), centrifugal compressors (Han et al, 2016), pumps (Asama et al, 2014; Masuzawa et al, 2003; Wang et al, 2019), and robot system (Cole and Fakkaew, 2018) because of its advantages on controllability (Barbaraci, 2016; Xiang and Tang, 2015), zero-friction (Barbaraci et al, 2013; Xiang and on Wong, 2019), and lubrication-free (Cui and Cui, 2017). The PID control is a common method (Ahrens et al, 1996; Parada et al, 2017; Tang et al, 2017; Wei and Söffker, 2016) to realize the displacement control of the magnetically suspended motor (MSM) rotor.…”