Power Supply

Why would you ever avoid taking the least expensive route? The parameters suggest that you wish to maintain a 60Hz frequency, so it seems pointless to consider a non-transformer approach.

Of course you can never rule out an homework question. Since you always have a way- but no more hints, since the question of not transformer for AC makes it as clear a candidate for homework as possible.

Hello SB,

I considered that this was potentially a homework question but it seemed a little too vague to be question designed by an instructor. And while I agree that CR4 is not to be used for homework, it does seem to offer some interesting and unexpected answers to real problems, especially for those new to a particular field of study.

But for general questions, it seems appropriate to use general answers, links to search engines, or Wikipedia, or to answer a question with another question.

So, be a good sport and toss out a silly suggestion if you like. You never know what spark of brilliance might be triggered from thinking outside the box for a question like this. Personally, I like the idea of a motor-generator set to convert the electrical energy into kinetic and back into electrical energy. But considering all of the coils in the motor, it could be counted as a rotating transformer and thereby be disqualified.

A simple voltage divider network using two capacitors (or if you are really desperate. two very LARGE wattage resistors). Don't forget the inrush-limiting resistor when using capacitors as a voltage divider network, least you let the light and smoke out of the capacitors.

Can you provide more details?

What about a nice Triac circuit?

If the source is 480V 3 phase then you can connect phase A to your right hand, phase C to your left hand and phase B to your nose.

Apply 480VAC power.

Your left and right foot should then produce a 220VAC single phase with your right foot being H and your right foot being N.