Re: Q about multi-phase motors.

["Tim Nichols" <tnichols@voicenet.com>]

It's hard to describe...the best thing to do is find a text book that graphs
3 phase sine waves together.  When you look at the different wave forms,
you'll see what I mean.
-----Original Message-----
From: Andrew Plumb <andrew@plumb.org>
To: ev@listproc.sjsu.edu <ev@listproc.sjsu.edu>
Date: Sunday, February 28, 1999 2:18 PM
Subject: Re: Q about multi-phase motors.


>At 02:01 PM 28/02/99 -0500, you wrote:
>>The reason why 3 phase is so popular, and we don't have 4, 5, or 6 phase,
is
>>that if you look at a graph of all three wave forms, you will see the
power
>>is conintuous.  When one wave form is at zero, the other two are at
nonzero
>>states.  Thus, there is no instant when a 3 phase system doesn't have the
>>same power level.  Not true of single or dual phase.
>>
>>Tim Nichols
>>tnichols@voicenet.com
>>'87 Electric Escort (Hope to be done by April)
>
>Could you point me to a reference on this?  I can see how the difference
>applies between 1, 2 and 3-phase systems, possibly 4 and 6-phase since you
>hit 0-V points for pairs 180 degrees out relative phase, but not how you've
>extended it to 5-phase.
>
>By 5-phase, I mean the driving voltages are 360/5=72 degrees out of phase
>from the next; only one of the five phases would be at 0-V at any one
>instant in time.  I would expect 5-phase to be even more stable than
>3-phase as a result.
>
>Andrew.
>
>P.S.  My background isn't in power, so if it's just a matter of reading
>some fundamentals on power electronics, please do point me in the right
>direction.
>
>
>Andrew Plumb
>mailto:andrew@plumb.org
>http://www.plumb.org/
>http://wwp.mirabilis.com/13667980
>
>