Dynamical Modeling of Passively Levitated Electrodynamic Thrust Self-Bearing Machines

Verdeghem, Joachim Van; Lefebvre, Martin; Kluyskens, Virginie; Dehez, Bruno

doi:10.1109/tia.2018.2880422

Cited by 24 publications

(6 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This small difference is probably caused by the mutual inductances that were neglected in the derivation process [33]. More accurate theoretical modeling might be possible considering the mutual inductances [26].…”

Section: B Axial Electrodynamic Stiffnessmentioning

confidence: 99%

“…Among these passive suspension techniques, electrodynamic suspension was chosen for this project, because the motor coils that generate torque are also used for passive stabilization, they provide stronger stiffness than that of room temperature diamagnetic levitation, and they do not require superconductors with a dedicated cooling system. The electrodynamic suspension principle was already employed in several electrodynamic bearings [14], [15], [16], [17], [18], [19], [20], [21], [22] and bearingless motors [23], [24], [25], [26], [27], [28], [29], [30], [31], [32], [33], [34], [35]. Full passive suspension was confirmed in a bearingless motor that combines axial electrodynamic suspension and radial permanent magnet bearings [29], [30], [31].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Experimental Verification of Passive Axial Electrodynamic Suspension in a Bearingless Motor

Rubio

KOMAL

Fujii

et al. 2023

IEEE Open J. Ind. Applicat.

View full text Add to dashboard Cite

This article investigates a bearingless motor with passive electrodynamic axial suspension. The axial suspension force is generated by a specific coil configuration called a figure-eight coil. Radial directions and tilting angles are stabilized by passive permanent magnet bearings. Since axial electrodynamic force increases with rotational speed, it must overcome a certain minimum threshold speed to compensate for the rotor weight and the unstable axial force caused by the permanent magnet bearing. Theoretical equations are derived for the braking torque caused by the suspension current and for the steady-state axial equilibrium position at constant rotational speed. A method based on the braking torque equation is proposed for correcting the mismatch between the magnetic center of the bearingless motor and the middle point of the axial clearance. This method sets the middle point between upper and lower touchdown positions in the same place where the motor current is minimum during passive axial suspension. Axial suspension is confirmed in the experiment with a noncontact laser sensor.

show abstract

Section: B Axial Electrodynamic Stiffnessmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Experimental Verification of Passive Axial Electrodynamic Suspension in a Bearingless Motor

Rubio

KOMAL

Fujii

et al. 2023

IEEE Open J. Ind. Applicat.

View full text Add to dashboard Cite

show abstract

“…The linearized model (x = X + x) of ( 6) and (7) [33,34] can be expressed in the s-domain by taking the Laplace transform as…”

Section: ( ) ( )mentioning

confidence: 99%

“…Condition I. Consider the control law(46) and (47) in closed-loop with pH system(34) and the Lyapunov candidate function V is the desired Hamiltonian energy function H…”

mentioning

confidence: 99%

Adaptive Control of Fuel Cell Converter Based on a New Hamiltonian Energy Function for Stabilizing the DC Bus in DC Microgrid Applications

et al. 2020

View full text Add to dashboard Cite

DC microgrid applications include electric vehicle systems, shipboard power systems, and More Electric Aircraft (MEA), which produce power at a low voltage level. Rapid developments in hydrogen fuel cell (FC) energy have extended the applications of multi-phase parallel interleaved step-up converters in stabilizing DC bus voltage. The cascade architecture of power converters in DC microgrids may lead to large oscillation and even risks of instability given that the load converters considered as loads feature constant power load (CPL) characteristics. In this article, the output DC bus voltage stabilization and the current sharing of a multi-phase parallel interleaved FC boost converter is presented. The extended Port-Hamiltonian (pH) form has been proposed with the robust controller by adding an integrator action based on the Lyapunov−Energy function, named “Adaptive Hamiltonian PI controller”. The stability and robustness of the designed controller have been estimated by using Mathematica and Matlab/Simulink environments and successfully authenticated by performing experimental results in the laboratory. The results have been obtained using a 2.5 kW prototype FC converter (by two-phase parallel interleaved boost converters) with a dSPACE MicroLabBox platform. The FC main source system is based on a fuel reformer engine that transforms fuel methanol and water into hydrogen gas H2 to a polymer electrolyte membrane FC stack (50 V, 2.5 kW).

show abstract

“…A bearing energy efficiency, defined as the ratio between the electrodynamic levitation force and the corresponding power losses, has been introduced as a performance criterion, even though external stiffnesses, such as the detent one, cannot be taken into account [16]. Recently, models describing both the axial quasi-static and dynamic behaviours of EDTBs have been derived and validated experimentally, allowing us to study their stiffness and rotational losses [17][18][19][20]. By contrast, although the beneficial effect of the external damping has been theoretically demonstrated, there is still no formula allowing us to determine the additional damping required to ensure the stability.…”

Section: Introductionmentioning

confidence: 99%

Stability and Performance Analysis of Electrodynamic Thrust Bearings

2019

Self Cite

View full text Add to dashboard Cite

Electrodynamic thrust bearings (EDTBs) provide contactless rotor axial suspension through electromagnetic forces solely leaning on passive phenomena. Lately, linear state-space equations representing their quasi-static and dynamic behaviours have been developed and validated experimentally. However, to date, the exploitation of these models has been restricted to basic investigations regarding the stiffness and the rotational losses as well as qualitative stability analyses, thus not allowing us to objectively compare the intrinsic qualities of EDTBs. In this context, the present paper introduces four performance criteria directly related to the axial stiffness, the bearing energy efficiency and the minimal amount of external damping required to stabilise the thrust bearing. In addition, the stability is thoroughly examined via analytical developments based on these dynamical models. This notably leads to static and dynamic conditions that ensure the stability at a specific rotor spin speed. The resulting stable speed ranges are studied and their dependence to the axial external stiffness as well as the external non-rotating damping are analysed. Finally, a case study comparing three topologies through these performance criteria underlines that back irons fixed to the windings are not advantageous due to the significant detent force.

show abstract

Dynamical Modeling of Passively Levitated Electrodynamic Thrust Self-Bearing Machines

Cited by 24 publications

References 26 publications

Experimental Verification of Passive Axial Electrodynamic Suspension in a Bearingless Motor

Experimental Verification of Passive Axial Electrodynamic Suspension in a Bearingless Motor

Adaptive Control of Fuel Cell Converter Based on a New Hamiltonian Energy Function for Stabilizing the DC Bus in DC Microgrid Applications

Stability and Performance Analysis of Electrodynamic Thrust Bearings

Contact Info

Product

Resources

About