Nonlinear Inductor

This example shows an implementation of a nonlinear inductor where inductance depends on current. A tanh function defines the nonlinear flux-current relationship. The flux saturates for large currents, which can occur, for example, in iron core inductors.

To model a specific flux-current relationship, you can replace the tanh function with a PS Lookup Table (1D) block.

For numerical efficiency, the underlying behavior is defined in terms of a current-dependent flux. A magnetizing lag helps with differentiating the flux to obtain voltage. The lag does not significantly affect simulation results, provided that the minimum time step is at least an order of magnitude greater than the lag time. Parameters for the source and lag are defined in the workspace so that the expected voltage can be calculated analytically.

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Nonlinear Inductor Subsystem

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