Variable Resistor with Variable Inductor
Purpose
Controlled resistance in series with controlled inductance
Library
Electrical / Passive Components
Description
This component models a variable resistor with a variable inductor connected in series. The resistance and inductance are determined by the signals fed into the inputs of the component. The voltage across this component is determined by the equation:
The control signal for the inductor must provide the values of both \(L\) and \(\frac{\mathrm{d}}{\mathrm{d}t}L\) in the following form: \(\left[ L_1\; L_2 \ldots L_n\; \frac{\mathrm{d}}{\mathrm{d}t}L_1\; \frac{\mathrm{d}}{\mathrm{d}t}L_2 \ldots \frac{\mathrm{d}}{\mathrm{d}t}L_n\right]\). It is the responsibility of the user to provide the appropriate signals for a particular purpose. For detailed information see the Variable Inductor.
If the component has multiple phases, you can choose to include the inductive coupling of the phases. In this case the control signal vector must contain the elements of the inductivity matrix (row by row) followed by their derivatives with respect to time, e.g. for two coupled phases: \(\left[ L_{11}\; L_{12}\; L_{21}\; L_{22}\; \frac{\mathrm{d}}{\mathrm{d}t}L_{11}\; \frac{\mathrm{d}}{\mathrm{d}t}L_{12}\; \frac{\mathrm{d}}{\mathrm{d}t}L_{21}\; \frac{\mathrm{d}}{\mathrm{d}t}L_{22}\right]\). The control signal thus has a width of \(2\cdot n^2\), \(n\) being the number of phases.
Note
The momentary inductance may not be set to zero. In case of coupled inductors, the inductivity matrix may not be singular.
The control signal for the momentary inductance values must be continuous. Discontinuous changes will produce non-physical results.
Parameters
- Inductive coupling
Specifies whether the phases should be coupled inductively. This parameter determines how the elements of the control signal are interpreted. The default is
off.- Initial current
The initial current through the component at simulation start, in amperes \((\mathrm{A})\). This parameter may either be a scalar or a vector corresponding to the implicit width of the component. The direction of a positive initial current is indicated by a small arrow in the component symbol. The default of the initial current is
0.
Probe Signals
- Inductor current
The current flowing through the inductor, in amperes \((\mathrm{A})\). The direction of a positive current is indicated with a small arrow in the component symbol.