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8458Controller delta vs WYE [was Re: Upgrade voltage - DC-DC Converter ...]

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  • geo_homsy2
    Oct 27, 2012
    • 0 Attachment
      Ahaa! Thanks, Wolf!

      --- In solectria_ev@yahoogroups.com, Wolf <wolf@...> wrote:
      >
      > The controller cares because the motor has twice the inductance when wired
      > in WYE, thus the phasor needs to be advanced to counteract the lagged
      > current.
      > On Oct 26, 2012 1:26 AM, "geo_homsy2" <geo.homsy@...> wrote:
      >
      > > **
      > >
      > >
      > > Hi Josh-
      > >
      > > I'm familiar with phasor analysis, and I understand the difference between
      > > a motor wired delta, and a motor wired wye. I like to think of it as
      > > changing the voltage- and current- constants of the motor, by a factor of
      > > sqrt(3) = 1.73, as you said.
      > >
      > > What I do NOT understand, however, is why the controller cares! Phases R,
      > > S, and T, should be basically the same, but 120 degrees out of phase.
      > > Period, end of story. I don't know why the controller wants to know the
      > > topology of what it's driving, as long as it's 3-fold symmetric.
      > >
      > > You had me confused with "I'm guessing that the controller was 'smart' and
      > > outputting 2 full power outputs, and 1 low voltage, like it should for
      > > WYE." I'm still confused by that. As you and I both said, all three outputs
      > > should be roughly the same but phase-shifted.
      > >
      > > Yours,
      > >
      > > //Geo
      > >
      > > --- In solectria_ev@yahoogroups.com, "otedawg" <joshua.orfield@> wrote:
      > > >
      > > > Geo,
      > > > Of course I can help out. I didn't know all of this till recently, but I
      > > am a EE and I have worked with power systems, but not motors before.
      > > >
      > > > I guess I'll start with Delta. Simply put, Delta is a motor wired in the
      > > shape of a delta (triangle). The controller outputs the same voltage on all
      > > three posts, and the motor runs in the correct direction based on the
      > > phasing of the wires. A 156V delta 3 phase system runs the 3 points of the
      > > triangle at a total of 78V to ground, and 156V across for phase A-B, B-C, &
      > > C-A. Phase: A is at 0degrees, B is at 120degrees, and C is at 240degrees.
      > > >
      > > > A WYE or Y motor is wired in the shape of a Y (hence the name). To
      > > control this motor, the controller runs similarly, but the voltage across
      > > each leg of the Y motor is lowered. (After EE magic, that number is 1.73).
      > > >
      > > > I'm not sure if I've explained or obfuscated the issue there. You've got
      > > to wrap your mind around the fact that there are 3 different voltage
      > > application locations, keep in mind that power is conserved (A delta motor
      > > will have it's current divided by 1.73, but a Y motor will have the voltage
      > > divided by 1.73), and stare at it long enough.
      > > >
      > > > Equations: http://www.watlow.com/reference/equations/0101.cfm
      > > > Motor Depictions: http://www.firstelectricmotor.com/images/motcon9.jpg
      > > >
      > > > Hopefully that's helpful.
      > > >
      > > > Thanks,
      > > > Josh
      > > >
      > > >
      > > >
      > > > --- In solectria_ev@yahoogroups.com, "geo_homsy2" <geo.homsy@> wrote:
      > > > >
      > > > > Hi Josh-
      > > > >
      > > > > question for you: You seem to know how the controller differs in its
      > > drive characteristics when it's configured for delta or for wye. Can you
      > > elucidate that for me, and for the other group members?
      > > > >
      > > > > I would've just assumed symmetric drive in both cases, and that's why
      > > I've never been able to understand WHY the controller has a setting for
      > > delta vs. wye.
      > > > >
      > > > > yours,
      > > > >
      > > > > //Geo
      > > > >
      > > > > --- In solectria_ev@yahoogroups.com, "otedawg" <joshua.orfield@>
      > > wrote:
      > > > > >
      > > > > > I have switched the motor from wye to delta, and back and forth when
      > > I was trying to test it. I'm confident that I've done it right. I even
      > > tested the leads to make sure the labeling is correct. I think that my
      > > problem was the .par file - I'm guessing that the controller was 'smart'
      > > and outputting 2 full power outputs, and 1 low voltage, like it should for
      > > WYE.
      > > > > >
      > > > > > I'm hoping that's the problem.
      > > > > >
      > > > > > Thanks,
      > > > > > Josh
      > > > > >
      > > > > > --- In solectria_ev@yahoogroups.com, Collin Kidder <collink@> wrote:
      > > > > > >
      > > > > > > The parameter file can now be found here:
      > > > > > >
      > > > > > > http://www.kkmfg.com/PAR-10-1631-0007_SO1083.par
      > > > > > >
      > > > > > > As I had mentioned, I went from delta to wye with a car. I got a
      > > new CCS
      > > > > > > and PAR file and I had to open the motor housing and switch around
      > > wires on
      > > > > > > terminals. The motor can be switched from delta to wye and back by
      > > > > > > loosening nuts and moving wires in the motor. Have you done that?
      > > > > > >
      > > > > > > On Wed, Oct 24, 2012 at 12:33 PM, otedawg <joshua.orfield@> wrote:
      > > > > > >
      > > > > > > > **
      > > > > > > >
      > > > > > > >
      > > > > > > > Collin,
      > > > > > > > Thanks for that - I'll try downloading and running with this
      > > file when I
      > > > > > > > get home today... And I just realized that I need the parameter
      > > (.par)
      > > > > > > > file, not the .ccs file. Could you upload such a file? Sorry for
      > > the
      > > > > > > > inconvenience.
      > > > > > > >
      > > > > > > > Hopefully the wye -> delta conversion is just a parameter
      > > change, not
      > > > > > > > something hidden that Azure uses...
      > > > > > > >
      > > > > > > > Thanks,
      > > > > > > > Josh
      > > > > > > >
      > > > > > > >
      > > > > > > >
      > > > > > >
      > > > > > >
      > > > > > > [Non-text portions of this message have been removed]
      > > > > > >
      > > > > >
      > > > >
      > > >
      > >
      > >
      > >
      >
      >
      > [Non-text portions of this message have been removed]
      >
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