Control system commissioning of fully levitated bearingless. The external motor drive itself is simply a copper winding solidstate whose magnetic field is regulated by an electronic controller to maintain the impeller rotational speed to any desired level. Dorrell pdf, this publication is mainly about bearingless machines, in which the magnetic levitation of this rotor is offered from inside the primary stator bore along with torque production when motoring, or electric power. Bearingless encoders from baumer excel by their wear free and magnetic scanning principle. Due to its excellent properties in addition to the bearingless torque motor s high torque density, it can be used where conventional gear motors can no longer be employed. In this paper, a simple, reliable and accurate analysis method is put forward using the concept of flux equivalent with virtual winding currents. A cryogenic highpowerdensity bearingless motor for future. In a sensorless drive, there are no discrete sensor units for measuring the rotor angle but the sensor functionality is integrated in the motor winding. A biased flux for producing radial levitation forces is provided by the permanent magnets, which reduce the power consumption of the system.
In conventional control method of suspension force for a bearingless brushless dc motor. Description quantity 1 5986560001 end cap assembly 151612 oring ports 2 1. Basic principles are described in detail with practical examples to aid understanding, and the different types of bearingless drives are introduced, along with coverage of test machines and applications. A bearingless motor utilizing a permanent magnet free structure for disposable centrifugal blood pumps. With this technology, contact free rotation and spatial suspension of a disk. Long life, high efficiency and maintenance free operation makes it ideal for use as a slowly rotating generator in the energy production. A key feature that distinguishes bearingless motor technology is that it combines both the motor and magnetic bearing in the same unit. The full suspension system dynamics, including both the destabilizing force due to the motor field and the active magnetic suspension control forces, are modeled, and a transfer function of the bearingless motor. With this technology, contact free rotation and spatial suspension of a disk or ringshaped rotor can be achieved.
Mar 14, 2012 the singledrive bearingless motor requires neither additional windings, nor inverters for noncontact magnetic suspension. Benefits and features of bearingless ac homopolar motor. Pdf design methodology for a special single winding. Magnetic bearings and bearingless drives by akira chiba, tadashi fukao, osamu ichikawa, masahide oshima, masatsugu takemoto and david g. Introduction t he bearingless slice motor was developed by schoeb and barletta 1. Bearingless encoders are robust and reliable even under the harshest environmental conditions such as cold, moisture and dirt. Thanks to the integration of the bearing and drive in a. In case of big axial suspension forces or strict requirements to axial positioning, an axial magnetic bearing needs to be.
Jsme journal of advanced mechanical design, systems, and manufacturing 93, 2015. Integrated solutions that leverage the motor s magnetic field to create magnetic bearing forces on the shaft eliminate the need for radial bearings and source of friction, energy losses and oil migration. Compared with bearing systems, bearingless encoders are very spacesaving due to their small installation depth. This offers advantages for disposable devices, such as. The motor is capable of producing 100 kw power for use in highspeed applications in industries. Development of a bearingless ammonia pump for spacecraft. Design of a bearingless blood pump natale barletta winterthur. With this technology, contact free rotation and spatial suspension of a disk or ringshaped rotor.
A new control method of suspension force for bearingless. To date, bearingless pumps have been implemented using the temple topology as it provides a relatively large free space above the rotor that can be used for the pump head. The magnetic levitation allows almost unlimited mechanical lifetime, abrasion and lubrification free operation and eliminates friction losses of any contacting parts. Additionally, the selected motor topology is optimized with finite element method fem simulations to improve the performance. Such bearingless motors with a magnet free rotor can save operational costs in applications that require disposable rotorimpeller units. A unit 101 of a first bearingless motor is formed of a stator 41 and a core 61, while a unit 103 of a second bearingless motor is formed of a stator 43 and a core 63. A high torque, wide air gap bearingless motor with permanent magnet free rotor t. A bearingless switchedreluctance motor for high specific power applications benjamin b. On a bearingless linear motor capable of selfmagnetic levitation wooyeon kim1, seungjong kim1, jongmin lee 1, sungchong chung2 and sang jo kim3 1energy mechanics research center, kist, 391 hawolgok, seongbukgu, seoul, 6791, korea. Motor s initial parameters are obtained through finite element method fem analyses. Introduction bearingless motors were introduced in the early 1990 1, 2. Magnetically levitated motor systems based around bearingless motors and generators and magnetic bearings offer a potential step change improvement in motor system lifetime and efficiency, solve critical challenges related to oillubricated contact bearings, and feature prognostic capabilities for conditionbased maintenance.
In short, the abi bearingless pump has only one moving part, requiring no shaft, seal, or bearing. Constant motor eciency and higher power factor longlasting reliability with thousands installed worldwide maintenance free, bearingless motor design smooth sostarting starting amps always below fullload amps hpm has virtually no degradation in speci. Levitronix is the first company to introduce the bearingless motor technology, a breakthrough in magnetic levitation, to the market. Structure diagram of the 5dof bearingless induction motor another structure 24. In case of big axial suspension forces or strict requirements to axial positioning, an axial magnetic bearing needs. In particular, the second bearingless motor stator includes halbach magnet arrays for homopolar fluxbiasing, which significantly improves the passive stiffness and also simplifies the design of the fluxbiasing structure.
A high torque, wide air gap bearingless motor with. This is composed of a singledrive bearingless motor and two repulsive passive magnetic bearings. Here, the magnet is eliminated from the rotor and placed on the stator to provide homopolar fluxbiasing to the rotor. The absence of mechanical contact between rotating and stationary parts leads to a virtually wear free product. Provided is a bearingless motor capable of stably performing magnetic levitation and rotation even when a thrust disk is not provided and gap length is wide. The oilfree, quiet, reliable and high efficiency motor has applications in hvac systems, large industrial blowers, turbines, compressors. This paper presents modelbased control mbc analyses of a bearingless interior permanent magnet motor ipmm. In the experiments, stable magnetic suspension and speed regulations are confirmed. The purpose of this paper is to choose a new topology for bearingless fluxswitching slice motors, regarding the number of stator and rotor poles, with a combined winding set.
This paper demonstrates by means of finiteelement analysis, that it is unrealistic to assume the two threephase windings to be decoupled from one another. Comparison of bearingless slice motor topologies for pump. In this paper, the modeling and control of reluctanceforcebased magnetic suspension in cylindrical rotor, ringshape air gap, bearingless motors are presented. Kolar this material is published in order to provide access to research results of the power electronic systems laboratory ditet eth zurich. This bearingless motor has the same drive components as the standard and wheel motors with the exception that the motor is assembled without the output shaft, bearings and bearing housing. In this paper, the design and operating principle of a slotless bearingless slice motor for high rotational speeds is presented. Keywords bearingless motor, homopolar bearing, passive stiffness. Actuators free fulltext modeling and realization of a. The motor under consideration includes two separate sets of threephase windings, one for torque production and the other one for radialforce production. Bearingless encoders rotary encoders angle sensors baumer. Bearingless slice drives feature a magneticallysuspended rotor disk. A motor generator comprises a stator, a rotor supported for movement relative to the stator, and a control system. Topology choice and optimization of a bearingless flux.
Magnetic bearings and bearingless drives akira chiba. Noise due to turbulence can only be heard at high flows. A single bearingless slice motor is at the same time a motor and a bearing system and is able to stabilise the six degrees of freedom of the pump impeller in a very simple way. Pdf ismb 15 fluxlinkage model including crosssaturation. This paper deals with magnetic modeling of a bearingless synchronous reluctance motor. In this paper, an additional advantage, an energysaving e. Motors initial parameters are obtained through finite element method fem analyses. In order to improve the performance of the bearingless induction motor bim under large disturbances such as parameter variations and load disturbances, an adaptive variablerated sliding mode controller asmc is designed to obtain better performance of the speed regulation system. Wear is limited to the pump head if is operated for extended periods with abrasive or aggressive chemicals. The term bearingless originates from the same idea as the term sensorless. Choi national aeronautics and space administration glenn research center cleveland, ohio 445 mark siebert university of toledo toledo, ohio 43606 a 128 switchedreluctance motor ref. Bearingless motor in cooling fan applications hiroya sugimoto. Therefore, the bearingless motor does not require maintenance of the bearing portion, and has an excellent feature such as a long life and high speed and high output. The proposed bearingless motor can realize energy conversion and produce 4dof radial forces compared with the conventional bearingless motor for improving the integration of system.
A novel singledrive bearingless motor with wide magnetic gap and high passive stiffness is proposed. Bearingless induction motors combining functions of both torque generation and noncontact magnetic suspension together have attracted more and more attention in the past decades due to their definite advantages of compactness, simple structure, less maintenance, no wear particles, high rotational speed, and so forth. It has only one threephase winding set and one threephase inverter. The decoupling control of the two sets is difficult and a key technology to stable operation for a bearingless motor. Since the fspm features a magnetfree rotor, rotor manufacturing costs. In experiments, the input power is measured with and without mechanical ball bearings. A control system for an electromagnetic rotary drive for bearingless motor generators comprises a winding configuration comprising a plurality of individual pole pairs through which phase current flows, each phase current producing both a lateral force and a torque. Homopolar bearingless slice motors with magnetfree rotors. Design process of the proposed singledrive bearingless motor is shown. The performance of the proposed concept is evaluated using an. This paper demonstrates by means of finiteelement analysis, that it is unrealistic to assume the two threephase windings to be.
Principle and test results of energysaving e ect of a single. May 15, 2009 a bearingless motor has two sets of intercoupling stator windings, namely torque windings and suspension force windings. Owing to the large possible magnetic gap and the ab. Install one shuttle valve poppet, spring and dash pot onto piston. Install one shuttle valve threaded internal hex plug with oring. Keywordsbearingless motor, homopolar bearing, passive stiffness. Kolar, fellow, ieee abstractthis paper presents a novel exterior rotor topology of a bearingless brushless synchronous motor with rated power of 300 w. Pdf modelling and modelbased control of a bearingless. Integrated solutions that leverage the motors magnetic field to create magnetic bearing forces on the shaft eliminate the need for radial bearings and source of friction, energy losses and oil migration. Bearingless induction motors combining functions of both torque generation and noncontact magnetic suspension together have attracted more and.
This paper overviews the key technologies of the bearingless induction motors. Request pdf a 150000 rpm bearingless slice motor in this paper, the design and operating principle of a slotless bearingless slice motor for high rotational speeds is presented. This work introduces a novel bearingless slice motor design. Pdf modelling and modelbased control of a bearingless 100. Magnetic bearings and bearingless drives 1st edition. In the center, the stator and the rotor of the bearingless motor are constructed with three axial layers. Pdf bearingless permanent magnet synchronous motor using.
In a prototype bearingless motor, the permanent magnet free rotor could be levitated and rotated at angular velocities of up to 3400 rpm with a rotational positioning accuracy of less than 27. Modeling and realization of a bearingless fluxswitching slice motor. Pdf bearingless permanent magnet synchronous motor bpmsm. The rotors radial translation is actively stabilized by superposing a twopole suspension flux on the homopolar bias flux. Modeling and realization of a bearingless fluxswitching. Bearingless motor was used for the first time by r. For a motor with low pressure relief valve, install poppet. The application of bearingless drives is emerging as an important technique in the areas of highspeed machinery and motioncontrol, and this book aims to provide a thorough grounding in the selection from magnetic bearings and bearingless drives book. Statespace models, controller and observer matrices. Design of a bearingless blood pump natale barletta. It is based on the new technology of the bearingless motor and is therefore called the bearingless blood pump.
This offers advantages for disposable devices, such as those used in the medical industry, and extends the range of bearingless slice motors toward high. Bearingless 300w pmsm for bioreactor mixing thomas reichert, student member, ieee, thomas nussbaumer, member, ieee, and johann w. The linz center of mechatronics gmbh is, therefore, researching the highspeed suitability of bearingless drives with a magnetic bearing integrated into the motor unit. Firstly, the l 1 norm of state variables is applied to the conventional exponential. Due to its excellent properties in addition to the bearingless torque motors high torque density, it can be used where conventional gear motors can no longer be employed. Bearingless induction motors combining functions of both torque generation and noncontact magnetic suspension together have attracted more and more attention in the past decades due to their. Homopolar bearingless slice motor in temple design conferences. A cryogenic highpowerdensity bearingless motor for future electric propulsion nasatm2008215211 june 2008 paper no. Pdf bearingless induction motors combining functions of both torque generation and noncontact magnetic suspension. Novel singledrive bearingless motor with wide magnetic.
In figure 3, the 4dof bearingless induction motor is split into two 2dof bearingless induction motors, which together provide the total torque and 2dof radial suspension of the rotor in the left and right shaft ends, respectively. The bearingless motor uses the electromagnetic force to support the rotor 11 in a noncontact manner. Bearingless motor design 201500601 university of minnesota. Oneaxis hysteresis motor driven magnetically suspended.
Principle and test results of energysaving e ect of a. Bearingless motors lcm linz center of mechatronics. A bearingless motor utilizing a permanent magnet free. A new control method of suspension force for bearingless brushless dc motor long shan, huangqiu zhu, weiyu zhang school of electrical and information engineering, jiangsu university, 2120 zhenjiang, china abstract. Aimed at practising electrical and mechanical engineers and advanced students, magnetic bearings and bearingless drives provides an essential. The bearingless motor is especially suited for applications such as gear boxes, winch. Abstractthis paper introduces a bearingless motor topology with a magnet free rotor, which enables higher rotor torque densities and wider. A bearingless switchedreluctance motor for high specific. Long life, high efficiency and maintenance free operation makes it ideal for use as. Hysteresis bearingless slice motors with homopolar fluxbiasing. Download magnetic bearings and bearingless drives pdf. The technology uses the same stator windingscoils and can use a standard variable speed drive for operation.
Permanent magnet polepair separated conical bearingless motors. The bearingless motor concept started developing and spreading in. Eaton charlynn vis 45 series bearingless motors parts and repair manual cmolotm006e march 2008 3 vis bearingless motors 45 series parts list ref. Internal or personal use of this material is permitted. Warbergeret al 50nm2500w bearingless motor for highpurity pharmaceutical mixing 2237 i. In contrast to stateoftheart bearingless slice motors, the rotor in this new design does not include any permanent rotor magnets. In this paper, a comprehensive framework for the multiphysics multiobjective optimal design of bsrms based on finiteelement method fem is proposed.
Pdf reluctance force magnetic suspension characteristics. Shuttle plug threads may have light coat of oil or preservative. Comparison of homopolar and heteropolar bearingless. Keywords linear motor, active magnetic bearing, magnetic levitation, bearingless motor introductions bearingless motor or selfbearing motor, which has been widely developed for artificial heart since 1990s, is a combination of electric motor. Pdf overview of bearingless induction motors researchgate. Energies free fulltext multiphysics multiobjective. Magnetic bearings and bearingless drives provides an essential guide to an area of engineering previously only fully covered by large. The bearingless switched reluctance motor bsrm integrates the switched reluctance motor srm with the magnetic bearings, which avoids mechanical bearingsloss and makes it promising in highspeed applications. Bearingless encoders rotary encoders angle sensors. Design methodology for a special single winding based bearingless switched reluctance motor. A cryogenic highpowerdensity bearingless motor for. Aimed at practising electrical and mechanical engineers and advanced students, magnetic bearings and bearingless drives provides an essential guide to an area of engineering previously only fully covered by large numbers of academic papers. This offers advantages for disposable devices, such as those used in the medical industry, and extends the range of bearingless slice motors toward.
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