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159 - Influence Analysis of Dimensional Tolerance using Morphing |
Module:DP |
2011-02-28 |
The angle of the magnets in SPM motors use a fillet or chamfer. However,
the fillet and chamfer of each product that is manufactured varies because
to completely fabricate the same fillet or chamfer is difficult in the
manufacturing process. Therefore, the dimensional tolerance is set so the
motor performance is not affected by these variations.
This example presents the use of a magnetic field analysis to compare whether
the cogging torque of the SPM motor is influenced by changing geometry
in the tolerance range assuming the dimensional tolerance of the chamfer
is ±0.4 mm.
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124 - Cogging Torque Analysis of an SPM Motor Accounting for an Varied
Stator Diameter
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Module:DS,DP |
2011-02-28 |
When a motor is constructed, the diameter of the stator becomes uneven
because of fabrication errors and shrink fitting. It is advantageous to
investigate the uneven diameter of the stator because it largely effects
the cogging torque.
This example presents the use of a structural and magnetic
field analysis to obtain the cogging torque with stator teeth that have
an uniform and varying diameter based on the displacement obtained with
a stress analysis.
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80 - Magnetization Analysis of an SPM Motor with a Skewed Magnet |
Module:TR |
2011-01-31 |
Motors are not only required to be more compact and have higher efficiency, but also to have less noise and vibration. One of the reasons of noise and vibration is cogging torque, which is caused by the interaction between the iron core and the permanent magnet. Cogging torque can be reduced by applying skew.
This note presents the use of magnetic field analysis to evaluate the magnetic flux density distribution and cogging torque of an SPM motor with a skewed magnet.
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54 - Cogging Analysis of a Moving Coil Linear Motor
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Module:TR |
2011-02-28 |
Linear motors are used for machine tools, carrier devices and so forth,
so it is very important for them to move smoothly and response quickly.
To do so, cogging needs to be reduced, since cogging causes the variation
in thrust force and speed. One method to reduce cogging is to skew the
magnet. This note presents the use of magnetic field analysis to obtain
the magnetic flux density distribution and cogging of a moving coil linear
motor with a skewed magnet.
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40 - Cogging Torque Analysis of an SPM Motor
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Module:DP |
2011-01-17 |
Cogging torque is produced by the interaction between the permanent magnet
and the stator core when the rotor rotates with no current flow. The cogging
torque prevents the smooth rotation of the rotor, which may lead to vibration
and noise. So the evaluation of the accurate cogging torque can be an important
issue. The period of the cogging torque is determined by the number of
poles and slots, so they are significant factors for evaluating cogging
torque.This note presents the use of magnetic field analysis for evaluating
the cogging torque of an 8-pole, 9-slot SPM motor, which has relatively
small period of the cogging torque.
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24 - Cogging Torque Analysis of an SPM Motor with a Skewed Stator
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Module:TR |
2011-02-28 |
For motors, there is a need of reducing vibration and noise. Cogging torque
is one cause of vibration and noise, so reducing cogging torque is an important
issue. And one way of reducing the cogging torque is to skew either the
rotor or the stator. This note presents the use of magnetic field analysis
to evaluate the cogging torque of an SPM motor with the skewed stator.
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 | 15 - Cogging Torque Analysis of an SPM Motor with a Step Skewed Magnet UP!
| Module:TR | 2012-04-10 | Reductions in vibration and noise are being sought after because they are a cause of torque variations in motors, and demands for reduction are particularly strong with motors that are used in machine tools and power steering. Cogging torque, which is a torque variation that is produced when there is no current, is generated because the electromagnetic force, which is produced in the gap, changes in relation to the rotor's rotation, making it necessary to apply skew to the stator and rotor and improvise with the magnet and stator's geometry in order to limit said variations in electromagnetic force as a countermeasure for reducing the torque variations. When applying skew, force in the thrust direction is produced in exchange for a reduction in the cogging torque, meaning that there is the disadvantage of producing eddy currents from the magnetic flux that links in the lamination direction.
Consequently, in order to accurately evaluate a motor that has skew applied, one needs a magnetic field analysis simulation that uses the finite element method (FEM), which can account for a detailed 3D geometry, instead of studies that use the magnetic circuit method or a 2D magnetic field analysis.
This Application Note presents the use of magnetic field analysis to evaluate the magnetic flux density distribution and cogging torque in each part of an SPM motor with a step skewed magnet.
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 | 2 - Cogging Torque Analysis of a PM Linear Motor UP!
| Module:TR | 2012-04-10 | Linear motors have been widely used in carrier devices and the drive units of machine tools due to their capability for high acceleration and deceleration, as well as their accurate positioning. As an issue for improving performance, people are trying to obtain a large thrust force in order to enhance responsiveness, but on the other hand it is also necessary to fulfill the demand for the trade-off of wanting to reduce thrust force variations and the attraction force.
In order to obtain a large thrust force, the material's nonlinear magnetic properties and the magnet's demagnetization characteristics need to be accounted for, and in order to evaluate thrust force variations, they need to be analyzed after modeling a detailed geometry. This is why they need to be studied with a magnetic field analysis simulation based on the finite element method (FEM).
This note presents how to obtain cogging torque, a cause of thrust variation, and evaluate the thrust force and attraction force during drive.
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