CAE Software【Femtet】Murata Software Co., Ltd.
General
Power generation of IPM generator is analyzed.
The power is generated in the coils of the stator by the rotor’s rotation.
The model is a permanent magnet synchronous motor with magnets built in the rotor.
The current generated by the rotor’s rotation is calculated.
The analysis is coupled with the external circuit.
The current and the magnetic flux density are solved.
Unless specified in the list below, the default conditions will be applied.
Item |
Settings |
Solver |
Magnetic Field Analysis [Luvens] |
Analysis Space |
2D |
Analysis Type |
Transient Analysis |
Unit |
mm |
Options |
Select External Circuit Coupling. Select Rotating machinery.
[Conversion] Model Thickness: 30×10^-3[m] Select Partial Model. Number of Divisions of the Whole Model: 2 Circuit Configuration Number of Series: 1 Circuit Configuration Number of parallels: 2 Select Convert the result to the whole model and output it. |
The Rotating Machinery tab is set as follows.
Tab |
Setting Item |
Settings |
Rotating Machinery |
Rotational Movement |
Select Constant Velocity Number of Rotations: 3000[r/min] Rotor’s Initial Rotation Position: 0[deg] |
Number of Slide Mesh Divisions |
Circumferential Division Angle: 1.0[deg] Rotation per Step: 3[mesh] Number of Slide Mesh Layers: 3 |
External circuit is as follows.
[R1] is a resistor to detect the generated power. It is placed where a battery is supposed to be placed.
Its value is set to be minute (0.001[Ohm]) for battery’s internal resistance.
Set the Mesh Tab as follows.
Tab |
Setting Item |
Settings |
Mesh |
Meshing Setup |
Automatically set the general mesh size: Deselect General mesh size: 1[mm] |
Ambient Air Creation |
Select Create ambient air automatically Ambient Air Scale: 1.25 |
The Transient Analysis tab is set up as follows.
The umber of steps is 180, circumferential division angle is 1.0[deg], and rotation per step is 3[mesh]. The rotation up to 540 degrees (=180*1.0*3) is analyzed.
Tab |
Setting Item |
Settings |
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Transient Analysis |
Time step |
Automatic |
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Table |
|
A rotor core and magnet are placed in the center. A stator and coils are placed around them.
This is a 2D model analysis. By utilizing the symmetry of the analysis model, it is made to be a half period symmetric model.
Half period rotation boundary (symmetry) is set.
“Ambient Air Creation” is selected.
Body Number/Type |
Body Attribute Name |
Material Name |
6/Sheet |
Mag1 |
mag |
7/Sheet |
Mag2 |
mag |
5/Sheet |
Rotor |
core |
20/Sheet |
Stator |
core |
22/Sheet |
U1+ |
Cu |
21/Sheet |
W1- |
Cu |
25/Sheet |
V1+ |
Cu |
23/Sheet |
U1- |
Cu |
26/Sheet |
W1+ |
Cu |
24/Sheet |
V1- |
Cu |
The body attribute is set up as follows.
Body Attribute Name |
Tab |
Setting |
Mag1 |
Direction |
Vector: X=1, Y=0, Z=1 |
Stator/Rotor/Air |
Rotor |
|
Mag2 |
Direction |
Vector: X=1, Y=0, Z=-1 |
Stator/Rotor/Air |
Rotor |
|
Rotor |
Stator/Rotor/Air |
Rotor |
Stator |
Stator/Rotor/Air |
Stator |
U1- |
Current |
Waveform: External Circuit Coupling Coil name on the circuit: U1 Turns: 15[Turns] Direction: – Y Direction |
Stator/Rotor/Air |
Stator |
|
U1+ |
Current |
Waveform: External Circuit Coupling Coil name on the circuit: U1 Turns: 15[Turns] Direction: +Y Direction |
Stator/Rotor/Air |
Stator |
|
V1- |
Current |
Waveform: External Circuit Coupling Coil name on the circuit: V1 Turns: 15[Turns] Direction: – Y Direction |
Stator/Rotor/Air |
Stator |
|
V1+ |
Current |
Waveform: External Circuit Coupling Coil name on the circuit: V1 Turns: 15[Turns] Direction: +Y Direction |
Stator/Rotor/Air |
Stator |
|
W1- |
Current |
Waveform: External Circuit Coupling Coil name on the circuit: W1 Turns: 15[Turns] Direction: – Y Direction |
Stator/Rotor/Air |
Stator |
|
W1+ |
Current |
Waveform: External Circuit Coupling Coil name on the circuit: W1 Turns: 15[Turns] Direction: +Y Direction |
Stator/Rotor/Air |
Stator |
The material properties are set as follows.
Material Name |
Tab |
Properties |
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Cu |
Conductivity |
Conductivity Type: Conductor Conductivity: 5.977×10^7[S/m] |
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mag |
Permeability |
Material Type: Permanent Magnet |
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Magnet |
Magnetization Characteristic Type: Linear Magnetization Strength: 1.25 Relative Permeability: 1.05 |
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core |
Permeability |
Magnetization Characteristic Type: Select B-H curve B-H Curve Table
|
One period symmetric boundary is set.
Boundary Condition Name/Topology |
Tab |
Boundary Condition Type |
Settings |
Symmetric |
Symmetry/Continuity |
Periodic |
Rotation Period (1 period) |
The distribution of the magnetic flux density at the rotation angle of 0[deg] is shown below.
In the result table, the generated current is output as the current of circuit component of resistor, which is for detecting the generated power.
The diagram below is time-generated current characteristic.
The generated power is about 75[A] on average from the current in the steady state.