Kevin wrote:
Fred wrote:
"The Natural Philosopher" wrote in message
...
Fred wrote:
"The Natural Philosopher" wrote in message
...
Fred wrote:
To get the advantages of 3 phase, each waveform has to be close to
sinusoidal.


No it doesn't.

3 phase as far as a motor is concerned, simply means it knows which
way to go round.
What on earth are you talking about? Are you seriously suggesting
that it doesn't matter what the waveform is for each of the phases,
that you can still tell me which way the motor will turn? Wow.


As long as they are 120 degrees apart, it doesn;t matter whether they
are sine, square or spikes. It will go round


If we're measuring degrees then it implies a sinusoid, though in
practise there would be harmonics of the fundamental.

If we apply an arbitrary waveform to each phase of a 3 phase motor, I
can assure you will not be able to tell which way it will turn.


you could if they followed each other like a normal 3 phase wave form
take 3 pulses as below (if it works)

_[]____[]_____
___[]____[]___
_____[]____[]__

thank you.