Modeling and Analysis of An Electric Motor with Step-Skewed Rotor

Limin
Limin
Altair Employee
edited October 28 in Altair HyperWorks

As an effective approach to reducing cogging torque, electromagnetic vibration, and noise, skewing is widely applied in the design of motors. For example, in the electric car Tesla Model 3, the rotor adopts a kind of step-skewing design, as shown below:

image

 

When performing an electromagnetic analysis of motors with a step-skewed rotor, due to its non-uniformity in the axial direction, it is impossible to perform two-dimensional equivalents directly through the cross-section. Generally, a three-dimensional model needs to be established for analysis, as shown below:

image

However, the 3D model-based analysis will require a relatively long solving time. The solver Flux provided another 2D model-based analysis method for the motor with step-skewing. The principle is to establish several 2D cross-sections for the motor (depending on the layer number of step-skewing). After solving these 2D problems, the results of the 3D model can be obtained by a homogenization technique. The above process can be realized in the SimLab EM solution – MT Skew.

This tutorial shows how to use SimLab-MTSkew to design and run the electromagnetic analysis for an electric motor with a step-skewed rotor.

 

Motor modeling

After building a 2D motor model, the step-skewing of the rotor can be defined in the solution settings.

image

 

Basic EM analysis

All physics definitions of the motor can be realized with the proposed [MT2D Workflow] tool bar:

image

 

The final physical description is shown below, with a coupled circuit:

image

 

After solving the scenario, SimLab can provide some basic post-processing for the EM analysis, including the isovalue visualization (in a 3D domain) and the physical quantity plotting.

image

image

============================================================================================================
Example access

All files corresponding to this example are accessible with this link:

Step to follow:

  • to follow the example step by step, the corresponding files are in "Example_name_StepByStep" folder containing:
    1. Tutorial folder: contains the document describing the example step by step
    2. Input folder: contains *.slb databases and files needed to build the example step by step
  • to play scripts, the corresponding files are in "Example_name_PlayScripts" folder containing:
    1. ScriptsTutorial folder: contains script files to be able to play each analysis
    2. Input folder: contains initial *.slb databases and all necessary files to play each analysis script

=============================================================================================================