The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform
E. M. Terentjev - One of the best experts on this subject based on the ideXlab platform.
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flii6 flij molecular motor assists with unfolding in the type iii secretion export apparatus
Scientific Reports, 2020Co-Authors: Jiri Kucera, E. M. TerentjevAbstract:: The role of rotational molecular motors of the ATP synthase class is integral to the metabolism of cells. Yet the function of FliI6-FliJ complex, a homolog of the F1 ATPase motor, within the flagellar export apparatus remains unclear. We use a simple two-state model adapted from studies of linear molecular motors to identify key features of this motor. The two states are the 'locked' ground state where the FliJ coiled coil filament experiences angular fluctuations in an asymmetric torsional potential, and a 'free' excited state in which FliJ undergoes rotational diffusion. Michaelis-Menten kinetics was used to treat transitions between these two states, and obtain the average angular velocity of the unloaded FliJ filament within the FliI6 stator: ωmax ≈ 9.0 rps. The motor was then studied under external counter Torque conditions in order to ascertain its maximal power output: Pmax ≈ 42 kBT/s (or 102 kW/mol), and the Stall Torque: GStall ≈ 3 kBT/rad (or 0.01 nN·nm/rad). Two modes of action within the flagellar export apparatus are proposed, in which the motor performs useful work either by continuously 'grinding' through the resistive environment of the export gate, or by exerting equal and opposite Stall force on it. In both cases, the resistance is provided by flagellin subunits entering the flagellar export channel prior to their unfolding. We therefore propose that the function of the FliI6-FliJ complex is to lower the energy barrier, and therefore assist in unfolding of the flagellar proteins before feeding them into the transport channel.
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flii6 flij molecular motor assists with unfolding in the type iii secretion export apparatus
bioRxiv, 2020Co-Authors: Jiri Kucera, E. M. TerentjevAbstract:The role of rotational molecular motors of the ATPase class is integral to the metabolism of cells. Yet the function of FliI6-FliJ complex - a homolog of the F1 ATPase motor - within the flagellar export apparatus remains unclear. We use a simple two-state model adapted from studies of linear molecular motors to identify key features of this motor. The two states are the 9locked9 ground state where the FliJ coiled coil filament experiences fluctuations in an asymmetric torsional potential, and a 9free9 excited state in which FliJ undergoes rotational diffusion. Michaelis-Menten kinetics was used to treat transitions between these two states, and obtain the average angular velocity of the FliJ filament within the FliI6 stator: Wmax = 9 rps. The motor was then studied under external counter-Torque conditions in order to ascertain its maximal power output: Pmax = 42 kT/s, and the Stall Torque: GStall = 3 kT/rad. Two modes of action within the flagellar export apparatus are proposed, in which the motor performs useful work either by continuously 9grinding9 through the resistive environment, or by exerting equal and opposite Stall force on it. In both cases, the resistance is provided by flagellin subunits entering the flagellar export channel prior to their unfolding. We therefore propose that the function of the FliI6-FliJ complex is to lower the energy barrier and therefore assist in unfolding of the flagellar proteins before feeding them into the transport channel.
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F_1 rotary motor of ATP synthase is driven by the torsionally-asymmetric drive shaft
Scientific Reports, 2016Co-Authors: O. Kulish, A. D. Wright, E. M. TerentjevAbstract:F_1F_0 ATP synthase (ATPase) either facilitates the synthesis of ATP in a process driven by the proton moving force (pmf), or uses the energy from ATP hydrolysis to pump protons against the concentration gradient across the membrane. ATPase is composed of two rotary motors, F_0 and F_1, which compete for control of their shared γ -shaft. We present a self-consistent physical model of F_1 motor as a simplified two-state Brownian ratchet using the asymmetry of torsional elastic energy of the coiled-coil γ -shaft. This stochastic model unifies the physical concepts of linear and rotary motors and explains the stepped unidirectional rotary motion. Substituting the model parameters, all independently known from recent experiments, our model quantitatively reproduces the ATPase operation, e.g. the ‘no-load’ angular velocity is ca. 400 rad/s anticlockwise at 4 mM ATP. Increasing the pmf Torque exerted by F_0 can slow, stop and overcome the Torque generated by F_1, switching from ATP hydrolysis to synthesis at a very low value of ‘Stall Torque’. We discuss the motor efficiency, which is very low if calculated from the useful mechanical work it produces - but is quite high when the ‘useful outcome’ is measured in the number of H^+ pushed against the chemical gradient.
H. Olsson - One of the best experts on this subject based on the ideXlab platform.
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a real time thermal model of a permanent magnet synchronous motor
IEEE Transactions on Power Electronics, 2010Co-Authors: Georgios Demetriades, E. Andersson, H Z De La Parra, H. OlssonAbstract:This paper presents a real-time thermal model with calculated parameters based on the geometry of the different components of a permanent-magnet synchronous motor. The model in state-space format has been discretized and a model-order reduction has been applied to minimize the complexity. The model has been implemented in a DSP and predicts the temperature of the different parts of the motor accurately in all operating conditions, i.e., steady-state, transient, and Stall Torque. The results have been compared with real measurements using temperature transducers showing very good performance of the proposed thermal model.
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A Real-Time Thermal Model of a Permanent Magnet Synchronous Motor Based on geometrical measures
2008 IEEE Power Electronics Specialists Conference, 2008Co-Authors: Georgios Demetriades, H. Zelaya, E. Andersson, H. OlssonAbstract:In the present paper the Real-Time Thermal Model (RTTM) is presented. The model has been developed in a Digital Signal Processor (DSP) and predicts the temperature of the different parts of the motor accurately in all operating conditions, thus, steady-state, transient and Stall Torque operation.
Hamid A. Toliyat - One of the best experts on this subject based on the ideXlab platform.
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Comparison of Surface Mounted Permanent Magnet Coaxial Radial Flux Magnetic Gears Independently Optimized for Volume, Cost, and Mass
IEEE Transactions on Industry Applications, 2018Co-Authors: Matthew C. Gardner, Benjamin E. Jack, Matthew Johnson, Hamid A. ToliyatAbstract:This study employs a genetic algorithm (GA) to optimize surface mounted permanent magnet coaxial radial flux magnetic gear designs using both 2-D finite element analysis (FEA) and 3-D FEA. Specifically, the GA optimizes different designs, which are all rated for a Stall Torque of 500 N·m and a gear ratio of approximately 5, to independently maximize volumetric Torque density (VTD), Torque per dollar (TPD), and gravimetric Torque density (GTD). Maximum VTDs of 274 and 210 kN·m/m3 were obtained with 2-D and 3-D simulations, respectively. Including the space required to provide an axial buffer for leakage flux resulted in a maximum leakage adjusted VTD of 162 kN·m/m3. Maximum TPDs of 5.86 and 5.47 N·m/$ were obtained with 2-D and 3-D simulations, respectively. Maximum GTDs of 102.8 and 86.8 N·m/kg were obtained with 2-D and 3-D simulations, respectively. The results demonstrate that independently maximizing these three metrics leads to markedly different designs with widely varying performance characteristics. The most significant differences occur between the maximum VTD and maximum TPD designs, and the analysis includes a thorough discussion of the dominant design parameters driving this phenomenon. Finally, the impacts of end effects on the optimal design parameters are also illustrated to demonstrate that consideration of these 3-D effects leads to significantly different performance predictions and to different optimal design selections.
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Comparison of Surface Mounted Permanent Magnet Coaxial Radial Flux Magnetic Gears Independently Optimized for Volume, Cost, and Mass
IEEE Transactions on Industry Applications, 2018Co-Authors: Matthew C. Gardner, Benjamin E. Jack, Matthew Johnson, Hamid A. ToliyatAbstract:This study employs a genetic algorithm (GA) to optimize coaxial radial flux magnetic gear designs using both 2D Finite Element Analysis (FEA) and 3D FEA. Specifically, the GA optimizes different designs, which are all rated for a Stall Torque of 500 N?m and a gear ratio of approximately 5, to independently maximize volumetric Torque density (VTD), Torque per dollar (TPD), and gravimetric Torque density (GTD). Maximum VTDs of 274 kN?m/m3 and 210 kN?m/m3 were obtained with 2D and 3D simulations, respectively. Maximum TPDs of 5.86 N?m/$ and 5.47 N?m/$ were obtained with 2D and 3D simulations, respectively. Maximum GTDs of 102.7 N?m/kg and 86.8 N?m/kg were obtained with 2D and 3D simulations, respectively. The results demonstrate that independently maximizing these three metrics leads to markedly different designs with widely varying performance characteristics. The most significant differences occur between the maximum VTD and maximum TPD designs, and the analysis includes a thorough discussion of the dominant design parameters driving this phenomenon. Finally, the impacts of end-effects on the optimal design parameters are also illustrated to demonstrate that consideration of these 3D effects leads to significantly different performance predictions and different
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Design, Construction, and Analysis of a Large-Scale Inner Stator Radial Flux Magnetically Geared Generator for Wave Energy Conversion
IEEE Transactions on Industry Applications, 2018Co-Authors: Matthew Johnson, Steven Englebretson, Matthew C. Gardner, Hamid A. Toliyat, Wen Ouyang, Colin TschidaAbstract:A magnetically geared machine (MGM) integrates a magnetic gear with a low-Torque, high-speed electric machine to create a single compact high-Torque, low-speed device with the size advantages of a mechanically geared system and the reliability of a direct drive machine. This work investigates the use of MGMs for wave energy conversion through the development of a large-scale magnetically decoupled inner stator radial flux magnetically geared generator rated for 10 kW at an input speed of 30 r/min. Critical design trends are illustrated using parametric two-dimensional and three-dimensional finite element simulation results. Information is also provided about the prototype's mechanical structure and key magneto-mechanical design considerations, including the impact of modulator bridges and the extent of axially escaping leakage flux. The prototype's experimental Stall Torque of 3870 Nm represents a 99.1% match with the simulated Stall Torque and corresponds to volumetric and gravimetric Torque densities of 82.8 kNm/m3 and 14.5 Nm/kg, respectively. Additionally, the prototype achieves an experimental efficiency of approximately 90% for operation near rated Torque. © 1972-2012 IEEE.
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Design, construction, and analysis of a large scale inner stator radial flux magnetically geared generator for wave energy conversion
2017 IEEE Energy Conversion Congress and Exposition (ECCE), 2017Co-Authors: Matthew Johnson, Steven Englebretson, Matthew C. Gardner, Hamid A. Toliyat, Wen Ouyang, Colin TschidaAbstract:A magnetically geared machine (MGM) integrates a magnetic gear with a low Torque, high speed electric machine to create a single compact high Torque, low speed device with the size advantages of a mechanically geared system and the reliability of a direct drive machine. This work investigates the use of MGMs for wave energy conversion through the development of a large scale magnetically decoupled inner stator radial flux magnetically geared generator rated for 10 kW at an input speed of 30 rpm. Critical design trends are illustrated using parametric 2D and 3D finite element simulation results. Information is also provided about the prototype's mechanical structure and key magneto-mechanical design considerations, including the impact of modulator bridges and the extent of axially escaping leakage flux. The prototype's experimental Stall Torque of 3870 N·m represents a 99.1% match with the simulated Stall Torque and corresponds to volumetric and gravimetric Torque densities of 82.8 kN·m/m3 and 14.5 N·m/kg, respectively. Additionally, the prototype achieves an experimental efficiency of approximately 90% over much of its operating range.
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Comparison of coaxial radial flux magnetic gears independently optimized for volume, cost, and mass
2017 IEEE International Electric Machines and Drives Conference (IEMDC), 2017Co-Authors: Matthew C. Gardner, Benjamin E. Jack, Matthew Johnson, Hamid A. ToliyatAbstract:This study employs a genetic algorithm (GA) to optimize coaxial radial flux magnetic gear designs using both 2D Finite Element Analysis (FEA) and 3D FEA. Specifically, the GA optimizes different designs, which are all rated for a Stall Torque of 500 N·m and a gear ratio of approximately 5, to independently maximize volumetric Torque density (VTD), Torque per dollar (TPD), and gravimetric Torque density (GTD). Maximum VTDs of 274 kNm/m3 and 210 kNm/m3 were obtained with 2D and 3D simulations, respectively. Maximum TPDs of 5.86 N·m/$ and 5.47 N·m/$ were obtained with 2D and 3D simulations, respectively. Maximum GTDs of 102.7 N·m/kg and 86.8 N·m/kg were obtained with 2D and 3D simulations, respectively. The results demonstrate that independently maximizing these three metrics leads to markedly different designs with widely varying performance characteristics. The most significant differences occur between the maximum VTD and maximum TPD designs, and the analysis includes a thorough discussion of the dominant design parameters driving this phenomenon. Finally, the impacts of end-effects on the optimal design parameters are also illustrated to demonstrate that consideration of these 3D effects leads to significantly different performance predictions and different optimal design selections.
Matthew Johnson - One of the best experts on this subject based on the ideXlab platform.
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Comparison of Surface Mounted Permanent Magnet Coaxial Radial Flux Magnetic Gears Independently Optimized for Volume, Cost, and Mass
IEEE Transactions on Industry Applications, 2018Co-Authors: Matthew C. Gardner, Benjamin E. Jack, Matthew Johnson, Hamid A. ToliyatAbstract:This study employs a genetic algorithm (GA) to optimize surface mounted permanent magnet coaxial radial flux magnetic gear designs using both 2-D finite element analysis (FEA) and 3-D FEA. Specifically, the GA optimizes different designs, which are all rated for a Stall Torque of 500 N·m and a gear ratio of approximately 5, to independently maximize volumetric Torque density (VTD), Torque per dollar (TPD), and gravimetric Torque density (GTD). Maximum VTDs of 274 and 210 kN·m/m3 were obtained with 2-D and 3-D simulations, respectively. Including the space required to provide an axial buffer for leakage flux resulted in a maximum leakage adjusted VTD of 162 kN·m/m3. Maximum TPDs of 5.86 and 5.47 N·m/$ were obtained with 2-D and 3-D simulations, respectively. Maximum GTDs of 102.8 and 86.8 N·m/kg were obtained with 2-D and 3-D simulations, respectively. The results demonstrate that independently maximizing these three metrics leads to markedly different designs with widely varying performance characteristics. The most significant differences occur between the maximum VTD and maximum TPD designs, and the analysis includes a thorough discussion of the dominant design parameters driving this phenomenon. Finally, the impacts of end effects on the optimal design parameters are also illustrated to demonstrate that consideration of these 3-D effects leads to significantly different performance predictions and to different optimal design selections.
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Comparison of Surface Mounted Permanent Magnet Coaxial Radial Flux Magnetic Gears Independently Optimized for Volume, Cost, and Mass
IEEE Transactions on Industry Applications, 2018Co-Authors: Matthew C. Gardner, Benjamin E. Jack, Matthew Johnson, Hamid A. ToliyatAbstract:This study employs a genetic algorithm (GA) to optimize coaxial radial flux magnetic gear designs using both 2D Finite Element Analysis (FEA) and 3D FEA. Specifically, the GA optimizes different designs, which are all rated for a Stall Torque of 500 N?m and a gear ratio of approximately 5, to independently maximize volumetric Torque density (VTD), Torque per dollar (TPD), and gravimetric Torque density (GTD). Maximum VTDs of 274 kN?m/m3 and 210 kN?m/m3 were obtained with 2D and 3D simulations, respectively. Maximum TPDs of 5.86 N?m/$ and 5.47 N?m/$ were obtained with 2D and 3D simulations, respectively. Maximum GTDs of 102.7 N?m/kg and 86.8 N?m/kg were obtained with 2D and 3D simulations, respectively. The results demonstrate that independently maximizing these three metrics leads to markedly different designs with widely varying performance characteristics. The most significant differences occur between the maximum VTD and maximum TPD designs, and the analysis includes a thorough discussion of the dominant design parameters driving this phenomenon. Finally, the impacts of end-effects on the optimal design parameters are also illustrated to demonstrate that consideration of these 3D effects leads to significantly different performance predictions and different
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Design, Construction, and Analysis of a Large-Scale Inner Stator Radial Flux Magnetically Geared Generator for Wave Energy Conversion
IEEE Transactions on Industry Applications, 2018Co-Authors: Matthew Johnson, Steven Englebretson, Matthew C. Gardner, Hamid A. Toliyat, Wen Ouyang, Colin TschidaAbstract:A magnetically geared machine (MGM) integrates a magnetic gear with a low-Torque, high-speed electric machine to create a single compact high-Torque, low-speed device with the size advantages of a mechanically geared system and the reliability of a direct drive machine. This work investigates the use of MGMs for wave energy conversion through the development of a large-scale magnetically decoupled inner stator radial flux magnetically geared generator rated for 10 kW at an input speed of 30 r/min. Critical design trends are illustrated using parametric two-dimensional and three-dimensional finite element simulation results. Information is also provided about the prototype's mechanical structure and key magneto-mechanical design considerations, including the impact of modulator bridges and the extent of axially escaping leakage flux. The prototype's experimental Stall Torque of 3870 Nm represents a 99.1% match with the simulated Stall Torque and corresponds to volumetric and gravimetric Torque densities of 82.8 kNm/m3 and 14.5 Nm/kg, respectively. Additionally, the prototype achieves an experimental efficiency of approximately 90% for operation near rated Torque. © 1972-2012 IEEE.
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Design, construction, and analysis of a large scale inner stator radial flux magnetically geared generator for wave energy conversion
2017 IEEE Energy Conversion Congress and Exposition (ECCE), 2017Co-Authors: Matthew Johnson, Steven Englebretson, Matthew C. Gardner, Hamid A. Toliyat, Wen Ouyang, Colin TschidaAbstract:A magnetically geared machine (MGM) integrates a magnetic gear with a low Torque, high speed electric machine to create a single compact high Torque, low speed device with the size advantages of a mechanically geared system and the reliability of a direct drive machine. This work investigates the use of MGMs for wave energy conversion through the development of a large scale magnetically decoupled inner stator radial flux magnetically geared generator rated for 10 kW at an input speed of 30 rpm. Critical design trends are illustrated using parametric 2D and 3D finite element simulation results. Information is also provided about the prototype's mechanical structure and key magneto-mechanical design considerations, including the impact of modulator bridges and the extent of axially escaping leakage flux. The prototype's experimental Stall Torque of 3870 N·m represents a 99.1% match with the simulated Stall Torque and corresponds to volumetric and gravimetric Torque densities of 82.8 kN·m/m3 and 14.5 N·m/kg, respectively. Additionally, the prototype achieves an experimental efficiency of approximately 90% over much of its operating range.
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Comparison of coaxial radial flux magnetic gears independently optimized for volume, cost, and mass
2017 IEEE International Electric Machines and Drives Conference (IEMDC), 2017Co-Authors: Matthew C. Gardner, Benjamin E. Jack, Matthew Johnson, Hamid A. ToliyatAbstract:This study employs a genetic algorithm (GA) to optimize coaxial radial flux magnetic gear designs using both 2D Finite Element Analysis (FEA) and 3D FEA. Specifically, the GA optimizes different designs, which are all rated for a Stall Torque of 500 N·m and a gear ratio of approximately 5, to independently maximize volumetric Torque density (VTD), Torque per dollar (TPD), and gravimetric Torque density (GTD). Maximum VTDs of 274 kNm/m3 and 210 kNm/m3 were obtained with 2D and 3D simulations, respectively. Maximum TPDs of 5.86 N·m/$ and 5.47 N·m/$ were obtained with 2D and 3D simulations, respectively. Maximum GTDs of 102.7 N·m/kg and 86.8 N·m/kg were obtained with 2D and 3D simulations, respectively. The results demonstrate that independently maximizing these three metrics leads to markedly different designs with widely varying performance characteristics. The most significant differences occur between the maximum VTD and maximum TPD designs, and the analysis includes a thorough discussion of the dominant design parameters driving this phenomenon. Finally, the impacts of end-effects on the optimal design parameters are also illustrated to demonstrate that consideration of these 3D effects leads to significantly different performance predictions and different optimal design selections.
Matthew C. Gardner - One of the best experts on this subject based on the ideXlab platform.
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Comparison of Surface Mounted Permanent Magnet Coaxial Radial Flux Magnetic Gears Independently Optimized for Volume, Cost, and Mass
IEEE Transactions on Industry Applications, 2018Co-Authors: Matthew C. Gardner, Benjamin E. Jack, Matthew Johnson, Hamid A. ToliyatAbstract:This study employs a genetic algorithm (GA) to optimize surface mounted permanent magnet coaxial radial flux magnetic gear designs using both 2-D finite element analysis (FEA) and 3-D FEA. Specifically, the GA optimizes different designs, which are all rated for a Stall Torque of 500 N·m and a gear ratio of approximately 5, to independently maximize volumetric Torque density (VTD), Torque per dollar (TPD), and gravimetric Torque density (GTD). Maximum VTDs of 274 and 210 kN·m/m3 were obtained with 2-D and 3-D simulations, respectively. Including the space required to provide an axial buffer for leakage flux resulted in a maximum leakage adjusted VTD of 162 kN·m/m3. Maximum TPDs of 5.86 and 5.47 N·m/$ were obtained with 2-D and 3-D simulations, respectively. Maximum GTDs of 102.8 and 86.8 N·m/kg were obtained with 2-D and 3-D simulations, respectively. The results demonstrate that independently maximizing these three metrics leads to markedly different designs with widely varying performance characteristics. The most significant differences occur between the maximum VTD and maximum TPD designs, and the analysis includes a thorough discussion of the dominant design parameters driving this phenomenon. Finally, the impacts of end effects on the optimal design parameters are also illustrated to demonstrate that consideration of these 3-D effects leads to significantly different performance predictions and to different optimal design selections.
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Comparison of Surface Mounted Permanent Magnet Coaxial Radial Flux Magnetic Gears Independently Optimized for Volume, Cost, and Mass
IEEE Transactions on Industry Applications, 2018Co-Authors: Matthew C. Gardner, Benjamin E. Jack, Matthew Johnson, Hamid A. ToliyatAbstract:This study employs a genetic algorithm (GA) to optimize coaxial radial flux magnetic gear designs using both 2D Finite Element Analysis (FEA) and 3D FEA. Specifically, the GA optimizes different designs, which are all rated for a Stall Torque of 500 N?m and a gear ratio of approximately 5, to independently maximize volumetric Torque density (VTD), Torque per dollar (TPD), and gravimetric Torque density (GTD). Maximum VTDs of 274 kN?m/m3 and 210 kN?m/m3 were obtained with 2D and 3D simulations, respectively. Maximum TPDs of 5.86 N?m/$ and 5.47 N?m/$ were obtained with 2D and 3D simulations, respectively. Maximum GTDs of 102.7 N?m/kg and 86.8 N?m/kg were obtained with 2D and 3D simulations, respectively. The results demonstrate that independently maximizing these three metrics leads to markedly different designs with widely varying performance characteristics. The most significant differences occur between the maximum VTD and maximum TPD designs, and the analysis includes a thorough discussion of the dominant design parameters driving this phenomenon. Finally, the impacts of end-effects on the optimal design parameters are also illustrated to demonstrate that consideration of these 3D effects leads to significantly different performance predictions and different
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Design, Construction, and Analysis of a Large-Scale Inner Stator Radial Flux Magnetically Geared Generator for Wave Energy Conversion
IEEE Transactions on Industry Applications, 2018Co-Authors: Matthew Johnson, Steven Englebretson, Matthew C. Gardner, Hamid A. Toliyat, Wen Ouyang, Colin TschidaAbstract:A magnetically geared machine (MGM) integrates a magnetic gear with a low-Torque, high-speed electric machine to create a single compact high-Torque, low-speed device with the size advantages of a mechanically geared system and the reliability of a direct drive machine. This work investigates the use of MGMs for wave energy conversion through the development of a large-scale magnetically decoupled inner stator radial flux magnetically geared generator rated for 10 kW at an input speed of 30 r/min. Critical design trends are illustrated using parametric two-dimensional and three-dimensional finite element simulation results. Information is also provided about the prototype's mechanical structure and key magneto-mechanical design considerations, including the impact of modulator bridges and the extent of axially escaping leakage flux. The prototype's experimental Stall Torque of 3870 Nm represents a 99.1% match with the simulated Stall Torque and corresponds to volumetric and gravimetric Torque densities of 82.8 kNm/m3 and 14.5 Nm/kg, respectively. Additionally, the prototype achieves an experimental efficiency of approximately 90% for operation near rated Torque. © 1972-2012 IEEE.
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Design, construction, and analysis of a large scale inner stator radial flux magnetically geared generator for wave energy conversion
2017 IEEE Energy Conversion Congress and Exposition (ECCE), 2017Co-Authors: Matthew Johnson, Steven Englebretson, Matthew C. Gardner, Hamid A. Toliyat, Wen Ouyang, Colin TschidaAbstract:A magnetically geared machine (MGM) integrates a magnetic gear with a low Torque, high speed electric machine to create a single compact high Torque, low speed device with the size advantages of a mechanically geared system and the reliability of a direct drive machine. This work investigates the use of MGMs for wave energy conversion through the development of a large scale magnetically decoupled inner stator radial flux magnetically geared generator rated for 10 kW at an input speed of 30 rpm. Critical design trends are illustrated using parametric 2D and 3D finite element simulation results. Information is also provided about the prototype's mechanical structure and key magneto-mechanical design considerations, including the impact of modulator bridges and the extent of axially escaping leakage flux. The prototype's experimental Stall Torque of 3870 N·m represents a 99.1% match with the simulated Stall Torque and corresponds to volumetric and gravimetric Torque densities of 82.8 kN·m/m3 and 14.5 N·m/kg, respectively. Additionally, the prototype achieves an experimental efficiency of approximately 90% over much of its operating range.
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Comparison of coaxial radial flux magnetic gears independently optimized for volume, cost, and mass
2017 IEEE International Electric Machines and Drives Conference (IEMDC), 2017Co-Authors: Matthew C. Gardner, Benjamin E. Jack, Matthew Johnson, Hamid A. ToliyatAbstract:This study employs a genetic algorithm (GA) to optimize coaxial radial flux magnetic gear designs using both 2D Finite Element Analysis (FEA) and 3D FEA. Specifically, the GA optimizes different designs, which are all rated for a Stall Torque of 500 N·m and a gear ratio of approximately 5, to independently maximize volumetric Torque density (VTD), Torque per dollar (TPD), and gravimetric Torque density (GTD). Maximum VTDs of 274 kNm/m3 and 210 kNm/m3 were obtained with 2D and 3D simulations, respectively. Maximum TPDs of 5.86 N·m/$ and 5.47 N·m/$ were obtained with 2D and 3D simulations, respectively. Maximum GTDs of 102.7 N·m/kg and 86.8 N·m/kg were obtained with 2D and 3D simulations, respectively. The results demonstrate that independently maximizing these three metrics leads to markedly different designs with widely varying performance characteristics. The most significant differences occur between the maximum VTD and maximum TPD designs, and the analysis includes a thorough discussion of the dominant design parameters driving this phenomenon. Finally, the impacts of end-effects on the optimal design parameters are also illustrated to demonstrate that consideration of these 3D effects leads to significantly different performance predictions and different optimal design selections.