The Experts below are selected from a list of 3354 Experts worldwide ranked by ideXlab platform
Johann Walter Kolar - One of the best experts on this subject based on the ideXlab platform.
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Active radial magnetic bearing for an ultra-high speed motor
2016 18th European Conference on Power Electronics and Applications EPE 2016 ECCE Europe, 2016Co-Authors: Marcel Schuck, Daniel Steinert, Johann Walter KolarAbstract:The miniaturization trend of electric machines increases the demand for higher rotational speeds to pro- vide a desired mechanical power level at decreased size. To push the limits of rotor miniaturization, new concepts for an ultra-high speed motor are researched, which employs sub-millimeter size rotors and is capable of achieving rotational speeds above 25 million rotations per minute (Mrpm). The rotor is sup- ported by means of a frictionless active magnetic bearing, which counteracts the gravitational force in vertical direction. Due to the low damping of the rotor, a magnetic bearing is also required in horizontal direction for to fully stabilize it. The respective system model, position sensor system and controller de- sign for such a magnetic bearing are outlined in this study. Experimental results demonstrate an increased horizontal damping of the rotor by a factor of more than 100.
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10 Mrpm spinning ball motor: Preparing the next generation of ultra-high speed drive systems
2010 International Power Electronics Conference - ECCE Asia - IPEC 2010, 2010Co-Authors: C. Wildmann, Thomas Nussbaumer, Johann Walter KolarAbstract:This paper presents conceptual ideas for an ultra-high speed spinning ball motor with a target speed in the range of several tens of million rotations per minute. The research should prepare the next generation of ultrahigh speed motors. The focus of this work is to investigate physical limitations and discuss feasible concepts for the realization of such drive systems. One major issue is the analysis of the mechanical stresses occurring in the rotor during centrifugal rotation with focus on the rotor shape by using 3D FEM simulation tools. Furthermore, magnetic levitation concepts for a friction-less bearing system are presented and discussed. Two alternative concepts for the position sensing system, which is necessary for detecting the rotor position for the magnetic bearing, are presented and compared. Finally, a first motor prototype is presented to offer basic behavioral insights into the system and its stability.
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Design considerations for the drive system of an ultra-high speed spinning ball motor
SPEEDAM 2010, 2010Co-Authors: C. Wildmann, Thomas Nussbaumer, Johann Walter KolarAbstract:This paper presents considerations for the drive system of a magnetically levitated ultra-high speed spinning ball motor. The system shall provide rotation speeds in the range of several million rotations per minute in future. In a first approach, the functionality is analyzed and verified on a system, which is enlarged by a factor of four compared to the motor size which shall provide the targeted rotational speed of the rotor. Possibilities of improvement for the final drive design are investigated in detail by using 3D FEM analysis. Finally, a new coreless drive unit, which shall provide higher rotor speeds of smaller rotors, is developed.
Marcel Schuck - One of the best experts on this subject based on the ideXlab platform.
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Active radial magnetic bearing for an ultra-high speed motor
2016 18th European Conference on Power Electronics and Applications EPE 2016 ECCE Europe, 2016Co-Authors: Marcel Schuck, Daniel Steinert, Johann Walter KolarAbstract:The miniaturization trend of electric machines increases the demand for higher rotational speeds to pro- vide a desired mechanical power level at decreased size. To push the limits of rotor miniaturization, new concepts for an ultra-high speed motor are researched, which employs sub-millimeter size rotors and is capable of achieving rotational speeds above 25 million rotations per minute (Mrpm). The rotor is sup- ported by means of a frictionless active magnetic bearing, which counteracts the gravitational force in vertical direction. Due to the low damping of the rotor, a magnetic bearing is also required in horizontal direction for to fully stabilize it. The respective system model, position sensor system and controller de- sign for such a magnetic bearing are outlined in this study. Experimental results demonstrate an increased horizontal damping of the rotor by a factor of more than 100.
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Characterization of Electromagnetic Rotor Material Properties and Their Impact on an Ultra-High Speed Spinning Ball Motor
IEEE Transactions on Magnetics, 2016Co-Authors: Marcel Schuck, Thomas Nussbaumer, Johann W. KolarAbstract:The ongoing miniaturization trend of electric machines increases the demand for higher rotational speeds to provide a required power level at decreased size. In this paper, new concepts for bearingless machines with ultra-high rotational speeds exceeding 25 million rotations per minute are researched. While the mechanical properties of the employed sub-millimeter-sized spherical steel rotors are documented, insufficient information is available on the electromagnetic characteristics that are crucial for magnetic levitation and acceleration. This paper outlines the relations between the relative permeability and conductivity of the rotor material and the achievable active magnetic bearing force and angular acceleration. Measured results for complete hysteresis curves of different rotor steels are presented.
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Rotor losses in an ultra-high speed spinning ball motor
2016 XXII International Conference on Electrical Machines (ICEM), 2016Co-Authors: Marcel Schuck, Daniel Steinert, Johann W. KolarAbstract:The ongoing miniaturization trend of electric machines demands for higher rotational speeds to provide a required power level at decreased size. The goal of this project is to push the limits of miniaturization by researching new concepts for bearingless machines with ultra-high rotational speeds exceeding 25 million rotations per minute (Mrpm). The employed sub-millimeter size spherical solid steel rotors are accelerated by the principle of a solid rotor induction machine. This study presents an analysis of the resulting eddy current losses and a thermal model of the rotor. The temperature of the rotor material is of interest, as it influences the achievable rotational speed at which failure of the rotor due to centrifugal loading occurs.
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Improved stator design for an ultra-high speed spinning ball motor
2016 International Symposium on Power Electronics Electrical Drives Automation and Motion (SPEEDAM), 2016Co-Authors: Marcel Schuck, Johann W. Kolar, Jannik Schafer, Daniel SteinertAbstract:The ongoing miniaturization trend of electric machines increases the demand for higher rotational speeds to provide a required power level at decreased size. The goal of this project is to push the limits of rotor miniaturization by researching new concepts for bearingless machines with ultra-high rotational speeds exceeding 25 million rotations per minute (Mrpm). Using a simple machine stator consisting of air coils limits the achievable rotor torque, which results in acceleration times of several hours until the aforementioned rotational speeds are reached. This study outlines the torque generation mechanisms of the machine and investigates the stator losses, from which improved stator designs, based on a ferrite core, are derived. The latter significantly increase the motor torque at decreased losses and facilitate fast acceleration of the rotor.
Johann W. Kolar - One of the best experts on this subject based on the ideXlab platform.
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Characterization of Electromagnetic Rotor Material Properties and Their Impact on an Ultra-High Speed Spinning Ball Motor
IEEE Transactions on Magnetics, 2016Co-Authors: Marcel Schuck, Thomas Nussbaumer, Johann W. KolarAbstract:The ongoing miniaturization trend of electric machines increases the demand for higher rotational speeds to provide a required power level at decreased size. In this paper, new concepts for bearingless machines with ultra-high rotational speeds exceeding 25 million rotations per minute are researched. While the mechanical properties of the employed sub-millimeter-sized spherical steel rotors are documented, insufficient information is available on the electromagnetic characteristics that are crucial for magnetic levitation and acceleration. This paper outlines the relations between the relative permeability and conductivity of the rotor material and the achievable active magnetic bearing force and angular acceleration. Measured results for complete hysteresis curves of different rotor steels are presented.
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Rotor losses in an ultra-high speed spinning ball motor
2016 XXII International Conference on Electrical Machines (ICEM), 2016Co-Authors: Marcel Schuck, Daniel Steinert, Johann W. KolarAbstract:The ongoing miniaturization trend of electric machines demands for higher rotational speeds to provide a required power level at decreased size. The goal of this project is to push the limits of miniaturization by researching new concepts for bearingless machines with ultra-high rotational speeds exceeding 25 million rotations per minute (Mrpm). The employed sub-millimeter size spherical solid steel rotors are accelerated by the principle of a solid rotor induction machine. This study presents an analysis of the resulting eddy current losses and a thermal model of the rotor. The temperature of the rotor material is of interest, as it influences the achievable rotational speed at which failure of the rotor due to centrifugal loading occurs.
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Improved stator design for an ultra-high speed spinning ball motor
2016 International Symposium on Power Electronics Electrical Drives Automation and Motion (SPEEDAM), 2016Co-Authors: Marcel Schuck, Johann W. Kolar, Jannik Schafer, Daniel SteinertAbstract:The ongoing miniaturization trend of electric machines increases the demand for higher rotational speeds to provide a required power level at decreased size. The goal of this project is to push the limits of rotor miniaturization by researching new concepts for bearingless machines with ultra-high rotational speeds exceeding 25 million rotations per minute (Mrpm). Using a simple machine stator consisting of air coils limits the achievable rotor torque, which results in acceleration times of several hours until the aforementioned rotational speeds are reached. This study outlines the torque generation mechanisms of the machine and investigates the stator losses, from which improved stator designs, based on a ferrite core, are derived. The latter significantly increase the motor torque at decreased losses and facilitate fast acceleration of the rotor.
Thomas Nussbaumer - One of the best experts on this subject based on the ideXlab platform.
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Characterization of Electromagnetic Rotor Material Properties and Their Impact on an Ultra-High Speed Spinning Ball Motor
IEEE Transactions on Magnetics, 2016Co-Authors: Marcel Schuck, Thomas Nussbaumer, Johann W. KolarAbstract:The ongoing miniaturization trend of electric machines increases the demand for higher rotational speeds to provide a required power level at decreased size. In this paper, new concepts for bearingless machines with ultra-high rotational speeds exceeding 25 million rotations per minute are researched. While the mechanical properties of the employed sub-millimeter-sized spherical steel rotors are documented, insufficient information is available on the electromagnetic characteristics that are crucial for magnetic levitation and acceleration. This paper outlines the relations between the relative permeability and conductivity of the rotor material and the achievable active magnetic bearing force and angular acceleration. Measured results for complete hysteresis curves of different rotor steels are presented.
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10 Mrpm spinning ball motor: Preparing the next generation of ultra-high speed drive systems
2010 International Power Electronics Conference - ECCE Asia - IPEC 2010, 2010Co-Authors: C. Wildmann, Thomas Nussbaumer, Johann Walter KolarAbstract:This paper presents conceptual ideas for an ultra-high speed spinning ball motor with a target speed in the range of several tens of million rotations per minute. The research should prepare the next generation of ultrahigh speed motors. The focus of this work is to investigate physical limitations and discuss feasible concepts for the realization of such drive systems. One major issue is the analysis of the mechanical stresses occurring in the rotor during centrifugal rotation with focus on the rotor shape by using 3D FEM simulation tools. Furthermore, magnetic levitation concepts for a friction-less bearing system are presented and discussed. Two alternative concepts for the position sensing system, which is necessary for detecting the rotor position for the magnetic bearing, are presented and compared. Finally, a first motor prototype is presented to offer basic behavioral insights into the system and its stability.
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Design considerations for the drive system of an ultra-high speed spinning ball motor
SPEEDAM 2010, 2010Co-Authors: C. Wildmann, Thomas Nussbaumer, Johann Walter KolarAbstract:This paper presents considerations for the drive system of a magnetically levitated ultra-high speed spinning ball motor. The system shall provide rotation speeds in the range of several million rotations per minute in future. In a first approach, the functionality is analyzed and verified on a system, which is enlarged by a factor of four compared to the motor size which shall provide the targeted rotational speed of the rotor. Possibilities of improvement for the final drive design are investigated in detail by using 3D FEM analysis. Finally, a new coreless drive unit, which shall provide higher rotor speeds of smaller rotors, is developed.
C. Wildmann - One of the best experts on this subject based on the ideXlab platform.
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10 Mrpm spinning ball motor: Preparing the next generation of ultra-high speed drive systems
2010 International Power Electronics Conference - ECCE Asia - IPEC 2010, 2010Co-Authors: C. Wildmann, Thomas Nussbaumer, Johann Walter KolarAbstract:This paper presents conceptual ideas for an ultra-high speed spinning ball motor with a target speed in the range of several tens of million rotations per minute. The research should prepare the next generation of ultrahigh speed motors. The focus of this work is to investigate physical limitations and discuss feasible concepts for the realization of such drive systems. One major issue is the analysis of the mechanical stresses occurring in the rotor during centrifugal rotation with focus on the rotor shape by using 3D FEM simulation tools. Furthermore, magnetic levitation concepts for a friction-less bearing system are presented and discussed. Two alternative concepts for the position sensing system, which is necessary for detecting the rotor position for the magnetic bearing, are presented and compared. Finally, a first motor prototype is presented to offer basic behavioral insights into the system and its stability.
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Design considerations for the drive system of an ultra-high speed spinning ball motor
SPEEDAM 2010, 2010Co-Authors: C. Wildmann, Thomas Nussbaumer, Johann Walter KolarAbstract:This paper presents considerations for the drive system of a magnetically levitated ultra-high speed spinning ball motor. The system shall provide rotation speeds in the range of several million rotations per minute in future. In a first approach, the functionality is analyzed and verified on a system, which is enlarged by a factor of four compared to the motor size which shall provide the targeted rotational speed of the rotor. Possibilities of improvement for the final drive design are investigated in detail by using 3D FEM analysis. Finally, a new coreless drive unit, which shall provide higher rotor speeds of smaller rotors, is developed.
