CAE Software【Femtet】Murata Software Co., Ltd.
Example15 Propulsion by Linear Motor
General
-
The propulsion by a coreless linear motor is analyzed.
-
The propulsion at a specified constant speed is solved.
-
The propulsion and the magnetic flux density distribution are solved.
-
The analysis is coupled with the external circuit.
-
Unless specified in the list below, the default conditions are applied.
Analysis Condition
|
Item |
Setting |
|
Analysis Space |
3D |
|
Unit |
mm |
|
Solver |
Magnetic Analysis [Luvens] |
|
Analysis Type |
Transient analysis |
|
Analysis Options |
Select External Circuit Coupling. Select Translating Machinery. |
The Translating Machinery tab is set as follows.
|
Tab |
Setting Item |
Setting |
|
Translating Machinery |
Translational Move |
Moving speed: 1.32[m/s] |
|
Number of Sliding Mesh Divisions |
Division size in traveling direction: 1.5[mm] Traveling quantity per step: 1[mesh] Number of sliding mesh layers: 3 |
External circuit is as follows.
3-phase AC of 60Hz and 10A is applied.
Set the Mesh Tab as follows.
|
Tab |
Setting Item |
Setting |
|
Mesh |
Meshing Setup |
Set the general mesh size automatically: Deselect General Mesh size: 1.5[mm] |
|
Automatic Ambient Air Creation |
Select Create ambient air automatically Ambient Air Scale: 2.0 |
The Transient Analysis tab is set up as follows.
The number of steps is 10, division size in the traveling direction is 1.5[mm], and traveling quantity per step is 1[mesh]. The mover’s travel up to 10*1.5*1=15[mm] is analyzed.
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As the input power is specified by current, the coil current is in the steady state from the beginning. The torque is also in the steady state.
|
Tab |
Setting Item |
Setting |
|||||
|
Transient analysis |
Timestep |
Automatic |
|||||
|
Table |
|
Model
The movers of 3-phase coils are placed in the center. The stators of magnets and yokes are placed on the sides of movers.
Side View
One End of the Model
Body Attributes and Materials
|
Body Attribute Name |
Material Name |
|
MagN |
000_Neodymium_magnet * |
|
MagS |
000_Neodymium_magnet * |
|
Yoke |
Yoke |
|
U1 |
008_Cu * |
|
V1 |
008_Cu * |
|
W1 |
008_Cu * |
* Available from the material DB
The body attribute is set up as follows.
|
Body Attribute Name |
Tab |
Setting |
|
MagN |
Direction |
Vector: X=0, Y=0, Z=1 |
|
Stator/Rotor/Air |
Stator |
|
|
MagS |
Direction |
Vector: X=0, Y=0, Z=-1 |
|
Stator/Rotor/Air |
Stator |
|
|
Yoke |
Stator/Rotor/Air |
Stator |
|
U1 |
Current |
Waveform: External circuit coupling Coil name on the circuit: FEM_Coil_1 Turns: 20[Turns] Direction: Loop coil/Magnetic field direction Magnetic field vector: 0, 0, 1 |
|
Stator/Rotor/Air |
Mover |
|
|
V1 |
Current |
Waveform: External circuit coupling Coil name on the circuit: FEM_Coil_2 Turns: 20[Turns] Direction: Loop Coil/Magnetic Field Direction Magnetic field vector: 0, 0, 1 |
|
Stator/Rotor/Air |
Mover |
|
|
W1 |
Current |
Waveform: External circuit coupling Coil name on the circuit: FEM_Coil_3 Turns: 20[Turns] Direction: Loop Coil/Magnetic Field Direction Magnetic field vector: 0, 0, 1 |
|
Stator/Rotor/Air |
Mover |
The material properties are set as follows.
|
Material Name |
Tab |
Properties |
|
Yoke |
Permeability |
Material type: Soft magnetic material |
|
Magnet |
Relative Permeability 3000 |
Boundary Condition
None
Results
The distribution of the magnetic flux density at a travel distance of 15mm (10 calculation steps) is shown below.
The diagram below shows time-propulsion characteristics. It is output to [mover/ X component] of [Electromagnetic force [N]] in the result table.
About 11[N] of propulsion is obtained.
