The Experts below are selected from a list of 32793 Experts worldwide ranked by ideXlab platform
Martin Doppelbauer - One of the best experts on this subject based on the ideXlab platform.
-
application of an amorphous core to an ultra high speed sleeve free interior permanent magnet rotor
IEEE Transactions on Industrial Electronics, 2018Co-Authors: Yingzhen Liu, Markus Schiefer, Patrick Breining, Francesco Grilli, Martin DoppelbauerAbstract:The low core losses and high yield strength of amorphous materials are attractive properties for ultra-high-speed rotor applications. This paper proposes an innovative interior permanent-magnet synchronous rotor for ultra-high-speed motors, which takes full advantage of those properties and eliminates the need for sleeves. In order to study the feasibility of the proposed rotor, the electromagnetic properties of the amorphous core are first measured and the challenges for producing such Rotors are subsequently discussed. Then, by using numerical methods, the electromagnetic, mechanical, and thermal performances of an example motor with an amorphous rotor core are evaluated and compared to those of a motor with a silicon steel rotor core. Through experimental characterization of the material and multiphysics numerical modeling of an example motor, it is shown that the amorphous material has great potential for producing high power density ultra-high-speed motors.
David G Dorrell - One of the best experts on this subject based on the ideXlab platform.
-
different arrangements for dual rotor dual output radial flux motors
IEEE Transactions on Industry Applications, 2012Co-Authors: Yuhan Yeh, Minfu Hsieh, David G DorrellAbstract:This paper describes different arrangements for a dual-rotor, radial-flux, and permanent-magnet brushless dc motor for application to variable-speed air conditioners. In conventional air conditioners, two motors of appropriate ratings are usually used to drive the condenser and evaporator separately. Alternatively, a motor with two output shafts may be employed, and this is studied here. The motor has inner and outer Rotors with a stator in between which is toroidally wound or axially wound with inner and outer slotted stator surfaces. The power sharing on the two Rotors is designed to meet the requirement of the condenser and evaporator. Finite element analysis (FEA) is employed to verify the designs. A prototype is made and tested to evaluate the performance. Alternative windings are investigated to assess the possibilities of decoupling the Rotors so that they run independently. In the final section, a new and novel arrangement is proposed, where one three-phase winding set and one two-phase winding set (both toroidal) are wound on the same stator to control two Rotors of different pole numbers. The two winding sets can be bifilar or share the same set of phase windings. This design simplifies the winding (because it is toroidal) and reduces the copper loss or amount of copper required. The design is tested using FEA solutions, and the initial results indicate that this machine could operate successfully.
-
performance improvement in high performance brushless rare earth magnet motors for hybrid vehicles by use of high flux density steel
IEEE Transactions on Magnetics, 2011Co-Authors: David G Dorrell, Andrew M Knight, Mircea PopescuAbstract:Hybrid and electrical vehicles use mostly high-efficiency brushless permanent-magnet AC motors and sinewave drives. The motors utilize rare-earth magnet material and also are required to have a very high torque-per-rotor volume. The designs are now very well refined and often use interior permanent-magnet (IPM) Rotors for a better field weakening control. This configuration has been shown to increase the efficiency. In this paper, the Toyota Prius 2004 motor is modeled using finite element analysis with different laminated steel materials in order to assess the effectiveness of using high flux-density steel versus the material volume. Additionally to the IPM rotor in the manufactured design, a spoke magnet rotor is also investigated. It is found that using high flux-density laminated steel will either increase the performance of the motor or allow the motor to be reduced in size (in this case, reduction in axial length).
-
different arrangements for dual rotor dual output radial flux motors
Energy Conversion Congress and Exposition, 2010Co-Authors: Yuhan Yeh, Minfu Hsieh, David G DorrellAbstract:This paper describes different arrangements for a dual-rotor, radial-flux, permanent-magnet brushless DC motor for application to variable-speed air conditioners. In conventional air conditioners, two motors of appropriate ratings are usually used to drive the condenser and evaporator separately. Alternatively, a motor with outputs on both sides of a common shaft may be employed and this is studied here. The motor has an inner and outer rotor with a stator in between which is toroidally-wound or axially-wound with inner and outer slotted stator surfaces. The power sharing on the two Rotors is designed to meet the requirement of the condenser and evaporator. 3D time-stepped finite element analysis (FEA) is employed (JMAG) to verify the designs. A prototype is made and tested to evaluate the performance. Alternative windings are investigated to assess the possibilities of decoupling the Rotors so that they run independently. In the final section a new and novel arrangement is described where one toriodal 3-phase winding set is used to control two Rotors, one inner and one outer, of different pole number. The design is tested using FEA solutions and the initial results indicate that this machine could operate successfully.
Dean R. Astumian - One of the best experts on this subject based on the ideXlab platform.
-
driving and controlling molecular surface Rotors with a terahertz electric field
ACS Nano, 2012Co-Authors: Jan Neumann, Kay E. Gottschalk, Dean R. AstumianAbstract:Great progress has been made in the design and synthesis of molecular motors and Rotors. Loosely inspired by biomolecular machines such as kinesin and the FoF1 ATPsynthase, these molecules are hoped to provide elements for construction of more elaborate structures that can carry out tasks at the nanoscale corresponding to the tasks accomplished by elementary machines in the macroscopic world. Most of the molecular motors synthesized to date suffer from the drawback that they operate relatively slowly (less than kHz). Here we show by molecular dynamics studies of a diethyl sulfide rotor on a gold(111) surface that a high-frequency oscillating electric field normal to the surface can drive directed rotation at GHz frequencies. The maximum directed rotation rate is 1010 rotations per second, significantly faster than the rotation of previously reported directional molecular Rotors. Understanding the fundamental basis of directed motion of surface Rotors is essential for the further development of efficient e...
-
Driving and Controlling Molecular Surface Rotors with a Terahertz Electric Field
2012Co-Authors: Jan Neumann, Kay E. Gottschalk, Dean R. AstumianAbstract:Great progress has been made in the design and synthesis of molecular motors and Rotors. Loosely inspired by biomolecular machines such as kinesin and the FoF1 ATPsynthase, these molecules are hoped to provide elements for construction of more elaborate structures that can carry out tasks at the nanoscale corresponding to the tasks accomplished by elementary machines in the macroscopic world. Most of the molecular motors synthesized to date suffer from the drawback that they operate relatively slowly (less than kHz). Here we show by molecular dynamics studies of a diethyl sulfide rotor on a gold(111) surface that a high-frequency oscillating electric field normal to the surface can drive directed rotation at GHz frequencies. The maximum directed rotation rate is 1010 rotations per second, significantly faster than the rotation of previously reported directional molecular Rotors. Understanding the fundamental basis of directed motion of surface Rotors is essential for the further development of efficient externally driven artificial Rotors. Our results represent a step toward the design of a surface-bound molecular rotary motor with a tunable rotation frequency and direction
Yingzhen Liu - One of the best experts on this subject based on the ideXlab platform.
-
application of an amorphous core to an ultra high speed sleeve free interior permanent magnet rotor
IEEE Transactions on Industrial Electronics, 2018Co-Authors: Yingzhen Liu, Markus Schiefer, Patrick Breining, Francesco Grilli, Martin DoppelbauerAbstract:The low core losses and high yield strength of amorphous materials are attractive properties for ultra-high-speed rotor applications. This paper proposes an innovative interior permanent-magnet synchronous rotor for ultra-high-speed motors, which takes full advantage of those properties and eliminates the need for sleeves. In order to study the feasibility of the proposed rotor, the electromagnetic properties of the amorphous core are first measured and the challenges for producing such Rotors are subsequently discussed. Then, by using numerical methods, the electromagnetic, mechanical, and thermal performances of an example motor with an amorphous rotor core are evaluated and compared to those of a motor with a silicon steel rotor core. Through experimental characterization of the material and multiphysics numerical modeling of an example motor, it is shown that the amorphous material has great potential for producing high power density ultra-high-speed motors.
Jan Neumann - One of the best experts on this subject based on the ideXlab platform.
-
driving and controlling molecular surface Rotors with a terahertz electric field
ACS Nano, 2012Co-Authors: Jan Neumann, Kay E. Gottschalk, Dean R. AstumianAbstract:Great progress has been made in the design and synthesis of molecular motors and Rotors. Loosely inspired by biomolecular machines such as kinesin and the FoF1 ATPsynthase, these molecules are hoped to provide elements for construction of more elaborate structures that can carry out tasks at the nanoscale corresponding to the tasks accomplished by elementary machines in the macroscopic world. Most of the molecular motors synthesized to date suffer from the drawback that they operate relatively slowly (less than kHz). Here we show by molecular dynamics studies of a diethyl sulfide rotor on a gold(111) surface that a high-frequency oscillating electric field normal to the surface can drive directed rotation at GHz frequencies. The maximum directed rotation rate is 1010 rotations per second, significantly faster than the rotation of previously reported directional molecular Rotors. Understanding the fundamental basis of directed motion of surface Rotors is essential for the further development of efficient e...
-
Driving and Controlling Molecular Surface Rotors with a Terahertz Electric Field
2012Co-Authors: Jan Neumann, Kay E. Gottschalk, Dean R. AstumianAbstract:Great progress has been made in the design and synthesis of molecular motors and Rotors. Loosely inspired by biomolecular machines such as kinesin and the FoF1 ATPsynthase, these molecules are hoped to provide elements for construction of more elaborate structures that can carry out tasks at the nanoscale corresponding to the tasks accomplished by elementary machines in the macroscopic world. Most of the molecular motors synthesized to date suffer from the drawback that they operate relatively slowly (less than kHz). Here we show by molecular dynamics studies of a diethyl sulfide rotor on a gold(111) surface that a high-frequency oscillating electric field normal to the surface can drive directed rotation at GHz frequencies. The maximum directed rotation rate is 1010 rotations per second, significantly faster than the rotation of previously reported directional molecular Rotors. Understanding the fundamental basis of directed motion of surface Rotors is essential for the further development of efficient externally driven artificial Rotors. Our results represent a step toward the design of a surface-bound molecular rotary motor with a tunable rotation frequency and direction
