Archive for February, 2008

Using Simulink to find equivalent resistance

February 23, 2008 3 comments

Matlab Simulink can be used to find the equivalent resistance between two nodes.

This model finds the equivalent resistance between the opposite corners of a cube where each edge is a resistor with an equivalent value.

The simulation calculates the equivalent resistance between two nodes in a complicated circuit.
Here all resistors are equal values and the equivalent resistance from node A to H
is .8333 * R (5/6*R), where R is the resistance of one resistor.

My method uses resistors from the SimPowerSystems toolbox in Simulink all given resistances of 1 ohm. A 1V source spans the resistors and the inverse of the current is the output value, the ratio of the equivalent resistance to that of one resistor.

Alternatively, this calculation is not really very hard by hand. You can see the steps to do so here:

You can download my Simulink model here: