Permanent Magnet Biased Bearing of Suspension System

2011 ◽  
Vol 383-390 ◽  
pp. 5529-5535
Author(s):  
Ming Zong ◽  
Xiao Kang Wang ◽  
Yang Cao
Keyword(s):  
Magnetic Field ◽  
Mathematical Model ◽  
Permanent Magnet ◽  
Power Amplifier ◽  
Model Simulation ◽  
Simulation Method ◽  
Magnetic Bearing ◽  
Magnetic Bearings ◽  
Active Magnetic Bearing ◽  
Simulation Results

PM (Permanent Magnet) biased magnetic bearing with PM to replace the magnetic field produced by electromagnet an Active Magnetic Bearing generated static bias magnetic field, it can reduce the power consumption of power amplifier to reduce the number of turns of magnet safety, reduce the volume of magnetic bearings, reducing electromagnetic coil operating current, thereby reducing the power amplifier power control system and heat sink size, magnetic bearings significantly reduce power loss, and fundamentally reduce the cost of bearing. In this paper, a kind of PM biased magnetic bearings, describes its structure and working principle, derived a mathematical model of magnetic bearing and magnetic circuit of PM biased magnetic bearings are calculated, given the specific PM biased magnetic bearing size and accordingly calculate the parameters of magnetic bearings. A magnetic model constructed using Simulink simulation method, and constructed using this method, magnetic bearing specific mathematical model simulation results show that the rotor position in the balance, X and Y decoupling between the control winding, while the deviation from equilibrium position time, X and Y control coupling between the windings, the simulation results and the calculation results.

Design and Testing of a Permanent Magnet Biased Active Magnetic Bearing

1999 ◽  
Author(s):  
Ross W. Overstreet ◽  
George T. Flowers ◽  
Gyorgy Szasz
Keyword(s):  
Permanent Magnet ◽  
Permanent Magnets ◽  
Experimental Testing ◽  
Control Strategies ◽  
Active Vibration Control ◽  
Electrical Current ◽  
Magnetic Bearing ◽  
Magnetic Bearings ◽  
Active Magnetic Bearing ◽  
Flux Flow

Abstract Magnetic bearings provide rotor support without direct contact. There is a great deal of current interest in using magnetic bearings for active vibration control. Conventional designs use electrical current to provide the bias flux, which is an integral feature of most magnetic bearing control strategies. Permanent magnet biased systems are a relatively recent innovation in the field of magnetic bearings. The bias flux is supplied by permanent magnets (rather than electrically) allowing for significant decreases in resistance related energy losses. The use of permanent magnet biasing in homopolar designs results in a complex flux flow path, unlike conventional radial designs which are much simpler in this regard. In the current work, a design is developed for a homopolar permanent magnet biased magnetic bearing system. Specific features of the design and results from experimental testing are presented and discussed. Of particular interest is the issue of reduction of flux leakage and more efficient use of the permanent magnets.

Reliability Analysis of Door Magnetic Switch under Different Permanent Magnetic Distribution

2012 ◽  
Vol 239-240 ◽  
pp. 328-331
Author(s):  
Xin Hua Yi ◽  
Xiao Min Cheng ◽  
Min Jun Wang
Keyword(s):  
Mathematical Model ◽  
Permanent Magnet ◽  
Reliability Analysis ◽  
Permanent Magnets ◽  
Simulation Method ◽  
Ansys Software ◽  
Reed Switch ◽  
Magnetic Switch ◽  
Magnetic Adsorption ◽  
Simulation Results

In order to improve the reliability and safety of door magnetic switch, a mathematical model of three reed switches was designed to satisfy this requirement under different permanent magnetic distribution. To obtain the same magnetic adsorption force for the magnetic reed switch, this paper uses a simulation method based on ANSYS software to mainly analyze the different distribution of three permanent magnets how to affect the adsorption force of door magnetic switch. The simulation results demonstrate that the adsorption force is different for different layout of permanent magnet and help to obtain the installing position of the reed switch and to improve the reliability.

The Active Magnetic Bearing Enables Optimum Control of Machine Vibrations

1985 ◽  
Author(s):  
Helmut Habermann ◽  
Maurice Brunet
Keyword(s):  
Magnetic Field ◽  
Control System ◽  
Magnetic Bearing ◽  
Magnetic Bearings ◽  
Active Magnetic Bearing ◽  
Electronic Control System ◽  
Electromagnetic Coils ◽  
Reaction Forces ◽  
Automatic Balancing ◽  
The Magnetic Field

The active magnetic bearing is based on the use of forces created by a magnetic field to levitate the rotor without mechanical contact between the stationary and moving parts. A ferromagnetic ring fixed on the rotor “floats” in the magnetic field generated by the electromagnets, which are mounted as two sets of opposing pairs. The current is transmitted to the electromagnetic coils through amplifiers. The four electromagnets control the rotor’s position in response to the signals transmitted from the sensors. The rotor is maintained in equilibrium under the control of the electromagnetic forces. Its position is determined by means of sensors which continuously monitor any displacements between rotor and stator through an electronic control system. As in every control system, damping of the loop is provided by means of a phase advance command from one or more differenciating circuits of the position error signal. The vibrations of the rotor and stator of a machine are generated by different forces: - centrifugal forces due to the misalignment between the geometrical axis and the inertial axis of the rotor (unbalance), - reaction forces due to aerodynamical forces on the rotor and stator blades. The active magnetic bearing allows the decrease and in many cases the fully cancelling of effects of these forces i.e. the vibrations of the machine. The inertial forces can be cancelled by shifting the axis of rotation of the rotor from the geometrical axis to the inertial axis (this system is usually called automatic balancing). The reaction forces due to aerodynamical effects can be cancelled by the creation by the magnetic bearings of forces in opposition. The vibrations are measured on the stator by accelerometers, and the signals drive magnetic bearings which generate forces having the same amplitude but in phase opposition. The improvement in vibrations amplitude usually ranges from 20 Db to 40 Db over a large band of frequencies.

scholarly journals Evaluation of the Topology of Switching Power Amplifiers for Active Magnetic Bearings

Proceedings ◽  
2020 ◽  
Vol 64 (1) ◽  
pp. 25
Author(s):  
Yefa Hu ◽  
Kezhen Yang ◽  
Xinhua Guo ◽  
Jian Zhou ◽  
Huachun Wu
Keyword(s):  
Power Amplifier ◽  
Power Amplifiers ◽  
Comprehensive Evaluation ◽  
Magnetic Bearing ◽  
Bias Current ◽  
Magnetic Bearings ◽  
Active Magnetic Bearing ◽  
Active Magnetic Bearings ◽  
Switching Power ◽  
Bearing System

A switching power amplifier is a key component of the actuator of an active magnetic bearing, and its reliability has an important impact on the performance of a magnetic bearing system. This paper analyzes the topologies of a switching power amplifier of an active magnetic bearing. In the case of different coil pair arrangements and bias current distributions, comprehensive evaluation of the different topologies of switching power amplifiers is introduced. This evaluation has a guiding role in the design of a switching power amplifier of an active magnetic bearing.

Commissioning and Control of the AMB Supported 3.5 kW Laboratory Gas Blower Prototype

2013 ◽  
Vol 198 ◽  
pp. 451-456 ◽  
Author(s):  
Rafał P. Jastrzębski ◽  
Alexander Smirnov ◽  
Katja Hynynen ◽  
Janne Nerg ◽  
Jussi Sopanen ◽  
...  
Keyword(s):  
Control System ◽  
Permanent Magnet ◽  
Induction Motor ◽  
Industrial Applications ◽  
Magnetic Bearing ◽  
Active Magnetic Bearing ◽  
Sensor Calibration ◽  
Full Potential ◽  
Disturbance Analysis ◽  
And Control

This paper presents the practical results of the design analysis, commissioning, identification, sensor calibration, and tuning of an active magnetic bearing (AMB) control system for a laboratory gas blower. The presented step-by-step procedures, including modeling and disturbance analysis for different design choices, are necessary to reach the full potential of the prototype in research and industrial applications. The key results include estimation of radial and axial disturbance forces caused by the permanent magnet (PM) rotor and a discussion on differences between the unbalance forces resulting from the PM motor and the induction motor in the AMB rotor system.

Calculation and Verification of Magnetic Field Parameters in Axial Active Magnetic Bearing

2014 ◽  
Vol 214 ◽  
pp. 143-150
Author(s):  
Piotr Graca
Keyword(s):  
Magnetic Field ◽  
Finite Element Method ◽  
Magnetic Force ◽  
Magnetic Bearing ◽  
Active Magnetic Bearing ◽  
Magnetic Flux Density ◽  
Two Dimensional ◽  
The Finite Element Method ◽  
Magnetic Field Computation

The paper presents numerical modeling of an Axial Active Magnetic Bearing (AAMB) based on two-dimensional (2D) magnetic field computation. The calculations, assisted by the Finite Element Method (FEM), have focused on the determination of the magnetic flux density and the magnetic force. Obtained magnetic field parameters were then measured and verified on a physical model.

Design of Control of DC Motor

2014 ◽  
Vol 611 ◽  
pp. 325-331
Author(s):  
Ľubica Miková ◽  
Michal Kelemen ◽  
Vladislav Maxim ◽  
Jaromír Jezný
Keyword(s):  
Mathematical Model ◽  
Virtual Environment ◽  
Computer Technology ◽  
Current Practice ◽  
Scientific Literature ◽  
Model Simulation ◽  
Graphical Interface ◽  
Dc Motors ◽  
Matlab Program ◽  
Simulation Results

In current practice the use of mathematical models is substantially widespread, reason being the recent increase in development of programs for this purpose, with the option of model simulation in a virtual environment, proportional to the evolving computer technology. The article contains a mathematical model created using Matlab program. The simulation results are compared with scientific literature that addresses DC motors and evaluated. For simplicity, a graphical interface was created.

Dynamic Modeling and Analysis of Active Magnetic Bearings

2014 ◽  
Vol 494-495 ◽  
pp. 685-688
Author(s):  
Rong Gao ◽  
Gang Luo ◽  
Cong Xun Yan
Keyword(s):  
Dynamic Characteristic ◽  
Dynamic Modeling ◽  
Magnetic Bearing ◽  
Integrated System ◽  
Magnetic Bearings ◽  
Active Magnetic Bearing ◽  
Active Magnetic Bearings ◽  
Modeling And Analysis ◽  
Amb System ◽  
Mathematics Method

Active magnetic bearing (AMB) system is a complex integrated system including mechanics, electronic and magnetism. In order to research for the basic dynamic characteristic of rotor supported by AMB, it is necessary to present mathematics method. The dynamics formula of AMB is established using theory means of dynamics of rotator and mechanics of vibrations. At the same tine, the running stability of rotor is analyzed and the example is presented in detail.

scholarly journals Development and Experimental Validation of Auxiliary Rolling Bearing Models for Active Magnetic Bearings (AMBs) Applications

2019 ◽  
Vol 2019 ◽  
pp. 1-19 ◽  
Author(s):  
Anna Tangredi ◽  
Enrico Meli ◽  
Andrea Rindi ◽  
Alessandro Ridolfi ◽  
Pierluca D’Adamio ◽  
...  
Keyword(s):  
Load Capacity ◽  
Critical Phenomenon ◽  
Magnetic Bearing ◽  
Design Tool ◽  
Magnetic Bearings ◽  
Active Magnetic Bearing ◽  
Active Magnetic Bearings ◽  
Short Period ◽  
Auxiliary Bearing ◽  
Bearing System

Nowadays, the search for increasing performances in turbomachinery applications has led to a growing utilization of active magnetic bearings (AMBs), which can bring a series of advantages thanks to their features: AMBs allow the machine components to reach higher peripheral speeds; in fact there are no wear and lubrication problems as the contact between bearing surfaces is absent. Furthermore, AMBs characteristic parameters can be controlled via software, optimizing machine dynamics performances. However, active magnetic bearings present some peculiarities, as they have lower load capacity than the most commonly used rolling and hydrodynamic bearings, and they need an energy source; for these reasons, in case of AMBs overload or breakdown, an auxiliary bearing system is required to support the rotor during such landing events. During the turbomachine design process, it is fundamental to appropriately choose the auxiliary bearing type and characteristics, because such components have to resist to the rotor impact; so, a supporting design tool based on accurate and efficient models of auxiliary bearings is very useful for the design integration of the Active Magnetic Bearing System into the machine. This paper presents an innovative model to accurately describe the mechanical behavior of a complete rotor-dynamic system composed of a rotor equipped with two auxiliary rolling bearings. The model, developed and experimentally validated in collaboration with Baker Hughes a GE company (providing the test case and the experimental data), is able to reproduce the key physical phenomena experimentally observed; in particular, the most critical phenomenon noted during repeated experimental combined landing tests is the rotor forward whirl, which occurs in case of high friction conditions and greatly influences the whole system behavior. In order to carefully study some special phenomena like rotor coast down on landing bearings (which requires long period of time to evolve and involves many bodies and degrees of freedom) or other particular events like impacts (which occur in a short period of time), a compromise between accuracy of the results and numerical efficiency has been pursued. Some of the elements of the proposed model have been previously introduced in literature; however the present work proposes some new features of interest. For example, the lateral and the axial models have been properly coupled in order to correctly reproduce the effects observed during the experimental tests and a very important system element, the landing bearing compliant suspension, has been properly modelled to more accurately describe its elastic and damping effects on the system. Furthermore, the model is also useful to characterize the frequencies related to the rotor forward whirl motion.

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