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Home / Tutorial / Magnetic Analysis (Luvens, Transient Analysis of Motor) / 07.Set the Analysis Conditions

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07.Set the Analysis Conditions

We set the analysis conditions.

Procedure

  1. On the [Model] tab, go to
    ,
    and click [Analysis Condition] .

    The [Analysis Condition Setting] dialog will show up.

 

 

  1. Select [Magnetic analysis 'Gauss/Luvens'] on the [Solver] tab.

 

  1. Click [Magnetic Analysis] tab and set as follows;

    Select [Analysis Type]: [Transient Analysis]

 

[Options]: [External Circuit Coupling], select [Rotating Machinery]

[Partial Model (Symmetric Model) Setting]:

           Select [Partial Model (Symmetric Model)]
Enter [Number of Divisions]: 2.

           Select [Convert].

           Enter [Number of Series]: 1.

           Enter [Number of Parallels]: 2.

Select [Convert results to full model for output].

 

  • Select [Partial Model] if a model is half or quarter symmetric.
    In [Number of Divisions (Full Model)], enter the number to divide the full model such as 2 or 4.

  • In [Conversion of external circuit I/O values], enter the number of coils in series and in parallels when a partial model is converted to a full model.
    See [Example of External Circuit Conversion Setup] for the details.
    See also [External Circuit Conversion].

  • If [Convert results to full model for output] is selected, the values in the results table, such as torque, will be converted for a full model.

 

  1. Click [Rotating Machinery] tab and set as follows;


    Select [Rotational Movement]: [Constant Velocity]enter [Number of Rotations]: 1800 [r/min]

    • The number of rotations of synchronous machine is expressed as follows.
      Ns=120*f/P
      where Ns is the number of rotations (synchronous speed)
      f is frequency [Hz] of AC power
      P is the number of poles

 

  1. Click [Transient Analysis] tab and set as follows;

    Enter [Number of Calculation Steps]:: 360.

 

  • The number of steps is 360, circumferential division angle is 1.0 [deg], and rotational quantity per step is 1 [mesh]. The mechanical angle rotation up to 360 [deg] (=360*1.0*1) is analyzed.
    It can be converted to the electric angle of 720[ deg] (=360*4/2) ,(mechanical angle) x (number of poles). Two periods of electric angle are analyzed.

 

  • As the input is by voltage for this model, the coil current is in the transient state in the initial stages. It will be some time before it reaches the steady state.
    Enough timesteps are secured in the steady state in this analysis condition.

 

  • To calculate the iron loss, it is necessary to set the timesteps for one period of electric angle in the steady state, and to define the iron loss characteristic for the material property.

 

  1. Click [Mesh] tab and set as follows;

    Deselect [Set the general mesh size automatically]Enter 1 in [General mesh size]

    Select [Create air domain automatically] and enter 1.25 in [Air Domain Scale].

    Click .

  2. The simulation accuracy varies depending on the mesh size and other settings.
    Details are described at [How to Optimize the Simulation Accuracy].
     

  • Body in the air domain will be created automatically when the meshing is performed.
    For detailed body shape and dimensions, please refer to the Air Domain Creation on the [Mesh] tab

 

The analysis conditions have been set.

 

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