List of generic advanced inputs

List of generic advanced inputs

  1. Number of computations per electrical period

    The number of computations per electrical period “ No. comp. / elec. period ” (Number of computations per electrical period) influences the accuracy of results and the computation time.

    The default value is 50. The minimum allowed value is 13. This default value provides a good compromise between the accuracy of results and computation time.

  2. Number of computed electrical periods

    The default value is 2. The minimum allowed value is 1 and the maximum value is equal to 10.

  3. Rotor initial position mode

    A relative angular position between the rotor and the stator must be considered.

    The relative angular position corresponds to the angular distance between direct axis of the rotor north pole and the axis of the stator phase 1 (reference phase).

    According to the input « Rotor initial position mode » (Rotor initial position mode), the angular position can be defined either automatically using an internal process of Altair® FluxMotor ® « Auto » (Automatic) or specified by the user « User » (User).

    By default, the “ Rotor initial position mode ” is set to “ Auto ”.

  4. Rotor initial position

    When the “ Rotor initial position mode ” is set to “ Auto ”, the initial position of the rotor is automatically defined by an internal process of FluxMotor

    The resulting relative angular position corresponds to the alignment between the axis of the stator phase 1 (reference phase) and the direct axis of the rotor north pole.

    When the “ Rotor initial position mode ” is set to “ User ”, the initial position of the rotor considered for computation must be set by the user in the field « Rotor initial position ». The default value is equal to 0. The range of possible values is [-360, 360].

  5. Mesh order

    To get results, Finite Element Modelling computations are performed.

    The geometry of the machine is meshed.

    Two levels of meshing can be considered: First order and second order.

    This parameter influences the accuracy of results and the computation time.

    The default level is second order mesh.

  6. Airgap mesh coefficient

    The advanced user input “ Airgap mesh coefficient ” is a coefficient which adjusts the size of mesh elements inside the airgap. When you decrease the value of “ Airgap mesh coefficient ”, you reduce the size of mesh elements, thus increasing the mesh density inside the airgap and the accuracy of results.

    The imposed Mesh Point (size of mesh elements touching points of the geometry), inside the Flux® software, is described as:

    MeshPoint = (airgap) x (airgap mesh coefficient)

    Airgap mesh coefficient is set to 1.5 by default.

    The variation range of values for this parameter is [0.05; 2].

    0.05 giving a very high mesh density and 2 giving a very coarse mesh density.

CAUTION:
Be aware, a very high mesh density does not always mean a better result quality.

However, this always leads to a huge number of nodes in the corresponding finite element model. So, it means a need of huge numerical memory and increases the computation time considerably.