Re: Q about multi-phase motors.

[Andrew Plumb <andrew@plumb.org>]

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