# Nonlinear Inductor

Discrete nonlinear inductor

• Library:
• Simscape / Electrical / Specialized Power Systems / Fundamental Blocks / Elements ## Description

The Nonlinear Inductor block represents a time-varying inductor. It implements a discrete variable inductor as a current source. The inductance is specified by a monotonically increasing flux linkage-current characteristic.

When you use a Nonlinear Inductor block in your model, set the powergui block Simulation type to `Discrete`. The robust discrete solver is used to discretize the electrical model.

### Equations

The block uses the following equations for the relationship between the voltage, v, across the device and the current through the inductor, i, and the flux linkage:

`$v=\frac{d\left(phi\right)}{dt}$`

`$phi=L\ast i=flux\text{\hspace{0.17em}}linkage.$`

## Ports

### Conserving

expand all

Specialized electrical conserving port associated with the inductor positive voltage.

Specialized electrical conserving port associated with the inductor negative voltage.

## Parameters

expand all

Robust integration method used by the block. The discrete solver method is automatically set to `Trapezoidal` when, in the powergui block, in the Preferences settings, you select Automatically handle discrete solver and Advanced tab solver settings of blocks.

The `Trapezoidal` robust solver is slightly more accurate than the `Backward Euler` robust solver, especially when the model is simulated at larger sample times. The `Trapezoidal` robust solver may produce slight damped numerical oscillations on machine voltage in no-load conditions, while the `Backward Euler` robust solver prevents oscillations and maintains good accuracy.

Resistance specified by a monotonically increasing flux linkage-current characteristic, specified as a 2-by-n matrix where n is greater than or equal to 2.

Measurement type. Select `Flux, Imag` to measure the flux and magnetization current of the nonlinear inductor. Place a Multimeter block in your model to display the selected measurements during the simulation.