How to achive mutual inductance and CM choke simulation in CircuitLab?

Question

This site is using CircuitLab. In some SPICE programs it is possible to simulate CM choke. For example:

Mutual Inductance is designated in a SPICE netlist by beginning the first word (label) of a new line with the letter "K". It is unique among the basic circuit elements in LTspice in that a schematic symbol is not used to represented it.

Is there a way to achieve this by using CircuitLab?

You could use a pair of voltage-controlled-voltage-sources (VCVS) in series with inductors but it is clumsy. https://www.circuitlab.com/forums/modeling-and-simulation/topic/75exru43/coupling-inductors/ Spice or Falstad Simulator it is far easier to define coupling ratio. — Tony Stewart EE75, Dec 21 '18 at 17:55

score 1 · Answer 1 · edited Mar 09 '21 at 20:42

(CircuitLab simulation engine author here -- just noticed this question!)
CircuitLab does support coupled inductors. Define a Parameter Element with a name like "K L1 L2". For example:

schematic

^{simulate this circuit – Schematic created using CircuitLab}

_{(Example adapted from: https://web.cecs.pdx.edu/~tymerski/ece222/How%20to%20create%20a%20transformer%20using%20LTSpice.pdf)}

It can also handle multiple inductors, and you can even do parameter sweeps over the coupling coefficient, for example:

schematic

^{simulate this circuit}

_{(Example adapted from: https://web.cecs.pdx.edu/~tymerski/ece222/How%20to%20create%20a%20transformer%20using%20LTSpice.pdf)}

Lp, Ls1, Ls2 effectively form a center-tapped transformer. If you run the simulation, this second example shows a parameter sweep which allows you to compare the results for different values of the coupling coefficient.

How to achive mutual inductance and CM choke simulation in CircuitLab?

1 Answers1