The Rotating Machinery, Magnetic (rmm) interface (
), found under the
AC/DC branch (
) when adding a physics interface, is used for design and analysis of electric motors and generators. Stationary and time-domain modeling is supported in 2D and 3D.
When this physics interface is added, these default nodes are also added to the Model Builder—
Electric Field Transformation,
Ampère’s Law,
Mixed Formulation Boundary,
Magnetic Insulation (the default boundary condition), and
Initial Values. Then, from the
Physics toolbar, add other nodes that implement, for example, boundary conditions and point conditions. You can also right-click
Rotating Machinery, Magnetic to select physics features from the context menu.
The Label is the default physics interface name.
The Name is used primarily as a scope prefix for variables defined by the physics interface. Refer to such physics interface variables in expressions using the pattern
<name>.<variable_name>. In order to distinguish between variables belonging to different physics interfaces, the
name string must be unique. Only letters, numbers, and underscores (_) are permitted in the
Name field. The first character must be a letter.
The default Name (for the first physics interface in the model) is
rmm.
Select an option from the Solve for list—
Full field (the default) or
Reduced field. For
Reduced field specify a
Background magnetic vector potential Ab (SI unit: Wb/m). The entered expressions must be differentiable.
For 2D components, enter a value or expression for the global Out-of-plane thickness d (SI unit: m). The default value of 1 m is typically not representative for a thin domain. Instead it describes a unit thickness that makes the 2D equation identical to the equation used for 3D components.
Select the Enable check box to allow the physics interface to control the meshing process. Information from the physics, such as the presence of infinite elements domain or periodic condition, will be used to set up automatically an appropriate mesh sequence.
Select the Activate port sweep check box and enter a
Sweep parameter name in the field. The default is
PortName.
The lumped parameters computed can be subject to a Touchstone file export. To activate this functionality, enter a file path or click
Browse to navigate to a file. Select a
Parameter format (value pairs) for the Touchstone export—
Magnitude and angle (MA) (the default),
Magnitude in dB and angle (DB), or
Real and imaginary parts (RI). Select the desired operation to perform from the
If file exists list—
Overwrite (the default) or
Create new. The latter is useful when the model is solved multiple times with different settings. Enter a
Reference impedance, Touchstone file export Zref (SI unit:
Ω). The default is 50
Ω.
When the Check applicability of features in study check box is selected, any features that are incompatible with the study will generate an error message when trying to solve or show the default solver. No solver will be generated. Deselect it and you will be able to run the model, possibly with runtime errors instead. It is available to allow the advanced user to tweak any feature and use it outside of its intended study scope.
The dependent variables (field variables) are the Magnetic vector potential A and the
Magnetic scalar potential Vm. The name can be changed but the names of fields and dependent variables must be unique within a model.
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