Assigning a Matrix

To solve for a capacitance, inductance, impedance, or conductance matrix:

Click Maxwell 2D or Maxwell 3D, and then select Parameters > Assign > Matrix.

The Matrix dialog box appears.
Click the Setup tab.
Type a name for the matrix in the Name box.
To specify the sources to be included in the matrix, do one of the following:
- For 3D Electrostatic, 2D and 3D Magnetostatic, 2D Eddy Current, and 3D Eddy Current T-W designs, select or clear the Include check box for any of the listed sources. For Maxwell 2D designs, the return path for each source may be specified. By default, the return path is at infinity; however, any conductor with a source specified can act as the return path.
- For 2D Electrostatic, 2D and 3D DC Conduction, 2D and 3D AC Conduction, and 3D Eddy Current A-F, select or clear the Signal or Ground check box for any of the listed sources. Grounded terminals are treated as reference voltages with zero voltage values. Excitations checked as Signal will be in the matrix (excited one at a time with 1 V during the parameters extraction process). Those excitations checked as Ground will be kept at 0 V and will not be part of the matrix. Any excitations not checked will not be considered.
For Magnetostatic designs, click the Post Processing tab.

If more than one source is listed on the left side, you can click the Post Processing tab and Group them to organize multiple sources into a single group. The calculations defined in the Post Processing tab do not impact the field solution and can be set up or changed after the solution has been completed.

To Group multiple sources together:
1. If desired, set the number of Turns for each source.
2. Select the sources to group in the list Entry list. Multiple source can be selected by holding the Ctrl key and clicking each source line.
3. With all sources selected, click Group to combine the sources into one series winding.
4. Set the number of parallel Branches the winding should be divided into and click OK.
5. The results of the post processing calculation on the matrix can be seen by selecting PostProcessed on the Matrix tab of the solutions dialog box.
Click OK.

Note:

For a matrix setup, the elements are defined based on excitations, not solids. Only excitations will be available in the Matrix dialog box, regardless of the current geometry selection. Also, changes made to the excitations after matrix setup will not be flagged until the setup validation performed prior to the solution process.
Matrix setups are recognized when coupling Maxwell designs to Twin Builder components such as Equivalent Circuit, Dynamic Inductance and Capacitance, and State Space. For more information on coupling Maxwell designs to Twin Builder components, refer to the Maxwell Component Subcircuits topic in the Twin Builder Help.
For 2D Eddy Current and 3D Eddy Current T-W designs, you can also Assign a Reduce Matrix.
For the 3D AC Conduction and 3D Eddy Current A-F solvers, the current excitations might also be considered during the matrix extraction. They will be considered in the same way as the regular voltage excitations.
The 3D Eddy Current A-F allows to extract both RL and CG matrices. For more information about the matrices setup, refer to Technical Notes: 3D Eddy Current A-F Parameter Extraction.

In a matrix calculation:

For coil terminals, all terminals are listed and can be selected.
For outer terminals, the solver can only handle a conduction path with two terminals, and only one terminal is listed for each conduction path:
If they are current terminals, the listed terminal is in the “in” direction.
If they are current density terminals, the first terminal is listed and can be selected.
When setting up an inductance matrix, the source must be a current excitation. Voltage sources cannot be used in this case.
In 2D matrix calculations, the solver calculates loop currents; therefore, the direction of return path current is always opposite of the source current. If a conductor with excitation is specified as the return path, the polarity setting of the excitation in the nominal problem setup is not respected.

Assigning a Matrix

In a matrix calculation:

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