I strongly suspect that your REAL requirement is to teach electrical practice.
No one is using Mozambique talent to design electrical circuits.
Since Red China is their current number one trade partner -- capital investment wise -- you need to steep yourself in their (Red China's) wiring schemes:
What the colors mean...
Three phase power...
OCPD...
and on it goes.
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If the crew really needs theory -- focus entirely on DC or AC until they've got it down pat.
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Personally, I would regard any attempt to teach DC theory a total waste of their time.
A second hand automobile alternator is an excellent asynchronous 3-phase power source. With one you can establish a field lab where the crew can prove up AC 3-phase theory...
By using human power to spin the alternator and displaying the juice on a second hand scope.
You'll want an alternator that provides easy access to the current AHEAD of the 3 rectifying diodes.
Once they're up to speed on this puppy, they can scale it up to the national grid in their minds.
