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I have been searching about it online but all I can find is info about a transformer. Am I missing something?

Here is the circuit:

enter image description here

This is the circuit I am trying to make:

enter image description here

JRE
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ELIZ
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    Three voltage sources forms a rigid loop. You may check the value of them or add a small resistance – emnha Sep 15 '21 at 03:56
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    I opt for small series resistance. `1m` ought to do it. Can either right-click the voltage source to add it, or add an explicit visual resistor. – Ste Kulov Sep 15 '21 at 04:10

4 Answers4

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Put low value impedances in the red positions shown: -

enter image description here

Maybe 1 milli ohm or a low value inductive reactance. Without those resistors you are forcing the sum of V1 and V2 to equal V3 and that ain't gonna happen. Or wire your supplies in star formation.

Andy aka
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Reconfigure your voltage sources into a Wye configuration. Putting your voltage zero refrerence at the centre of the Wye would probably give you waveforms that were easier to interpret anyway.

Or omit one of the voltage sources. Its voltage is automatically provided by the other two.

Spice cannot solve, so does not allow, a zero impedance loop, which you have with a Delta voltage source configuration, even if you've carefully crafted the voltages to be consistent. The other thing it disallows is an open circuit node, for instance one with only capacitors connected. Either configuration leads to more variables than there are unique equations, and the resulting matrix becomes singular, or non-invertible. You can add series resistance to the loop, or shunt resistance to a node, to fix it, but it's better to avoid the configuration if you can.

Neil_UK
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You can't have a loop of voltage sources (or including inductors) in SPICE. The current that flows in the loop is indeterminate.

Just remove one of the V sources (leave it open circuit).

jp314
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To be able to simulate a three-phase power, transform "delta"-connected voltage sources of your circuit to "wye"-connected voltage sources (delta-wye transform).

V.V.T
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