For some reasons, I want to connect secondary sides of two transformers in series as you see in the schematics.
Computer simulation is as you see in the graph. (Notice that the corresponding signal values \$V_{out1}\$ and \$V_{out2}\$ are printed at the right side for the graph.)
The two transformers are identical. Their electrical parameters are shown in the image above. Their dot-conventions are shown in the schematics.
The load will not always be resistive; it can be a more complex circuit with an arbitrary impedance value, or it can be a diode rectifier. And, of course, it is assumed that all of the circuit elements will stay in their rated working range.
My question is, would this circuit work in practice? Could there be any instability or any other unpredictable problem? Is there any reason that you wouldn't advice me to use this configuration?
Best Answer
As long as both secondaries are rated for the same current, that should work fine. If they have different current ratings, you will want to take no more current than the lower of the two.
The main thing is to keep track of the polarities, i.e., the placement of the dots. With series secondaries, if you get one winding flipped, the secondaries will be out-of-phase and you won't get any current, assuming the secondary voltages are the same. If they aren't, the higher voltage secondary would drive current against the lower voltage one, but just keep the dots straight and this is not a concern.
The real hazard is when you try to put secondaries in parallel. Get the dots wrong on this setup, and the two secondaries become a short circuit. Much smoke will follow.