[Amps] Benefits of 3-phase power?

[kayser at sympatico.ca]

wb8jkr wrote.... 
>   My understanding is that 60 Hz was the best "compromise"
> between the amount tolerable losses and the amount of required
> iron.

And some of the issues were transmission losses and the quality and consistency of the iron available for transformers and motors.

Very large converters for VHV, Very High Voltage DC transmission are normally mechanical and very large.  I read of one that was cryogenically cooled.

Remember that 400 Hz in WWII and afterwards was a very serious stretch for the aircraft service - the RF noise was terrific.  I can remember we once stripped all the 400 Hz out of several aircraft in a hurry so we could hear something on HF.

Again I plead with anyone who is considering three phase for any project to do a study in detail to see what happens when one or two of the phases disappear.  I have a very special and expensive box that watches all three phases on a facility I look after and it chops everything if any of the phases present low or over voltage conditions.  Three phase motors really get sick fast when one phase drops out - very expensive as they are the big motors....

Larry
VA3LK