1. Attachments are working again! Check out this thread for more details and to report any other bugs.

mg2

Discussion in 'Generation 1 Prius Discussion' started by shagpal, Apr 21, 2015.

  1. shagpal

    shagpal Junior Member

    Joined:
    Feb 18, 2006
    19
    1
    0
    this is a kinda crazy thought, but I did this kinda stuff with older vehicles.

    has anyone checked if a gen2 mg2 will fit in our gen1 transaxles? if it could physically fit, what are the possibility of actually making it work?
     
  2. JimboPalmer

    JimboPalmer Tsar of all the Rushers

    Joined:
    Apr 14, 2009
    12,470
    6,862
    2
    Location:
    Greenwood MS USA
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    This is idle speculation, but the Gen 1 battery is a different voltage than the Gen 2, so I suspect the windings on MG/2 are different as well
     
  3. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    23,073
    14,980
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV


    A lot changed, including the voltage it operates at. You're looking at easily a senior-thesis level of research and improvisation to get it to work, if that's what you're looking for (though a good thesis would start by explaining why this would be a good thing to do in the first place). :)

    -Chap
     
  4. shagpal

    shagpal Junior Member

    Joined:
    Feb 18, 2006
    19
    1
    0
    isnt gen2 mg2 more powerful motor than gen1 mg2?

     
  5. dolj

    dolj Senior Member

    Joined:
    May 14, 2012
    7,448
    3,751
    0
    Location:
    Wellington, New Zealand
    Vehicle:
    2007 Prius
    Model:
    N/A
    I think if you are asking that question after Chap posted the above reply, you should stay well away from the idea you have put forward.
     
  6. shagpal

    shagpal Junior Member

    Joined:
    Feb 18, 2006
    19
    1
    0
    no, I am just asking, not doing

     
  7. bwilson4web

    bwilson4web BMW i3 and Model 3

    Joined:
    Nov 25, 2005
    27,068
    15,372
    0
    Location:
    Huntsville AL
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Plus
    My understanding is the NHW20 MG2 could be made into an electrically identical to NHW11 MG2 by rewiring the stator coils so some are parallel instead of series. Of course there may be mechanical fit issues that would have to be checked.

    Running the stator coils in series instead of parallel reduces the current but requires a higher voltage. In series, the (I**2)*R losses are significantly reduced.

    Bob Wilson
     
    #7 bwilson4web, Apr 22, 2015
    Last edited: Apr 22, 2015
  8. shagpal

    shagpal Junior Member

    Joined:
    Feb 18, 2006
    19
    1
    0
    #8 shagpal, Apr 22, 2015
    Last edited: Apr 22, 2015
  9. shagpal

    shagpal Junior Member

    Joined:
    Feb 18, 2006
    19
    1
    0
    hi bob, are you referring to possibly rewiring something going to mg2, or rewinding coils within mg2?

     
  10. bwilson4web

    bwilson4web BMW i3 and Model 3

    Joined:
    Nov 25, 2005
    27,068
    15,372
    0
    Location:
    Huntsville AL
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Plus
    Soldering the leads in parallel instead of series. No rewinding.

    Bob Wilson
     
    #10 bwilson4web, Apr 22, 2015
    Last edited: Apr 22, 2015
  11. shagpal

    shagpal Junior Member

    Joined:
    Feb 18, 2006
    19
    1
    0
    ok, as I understand it, the gen2 mg2 is rated 50kw, and the gen1 mg2 is 33kw.

    I know this is a stretch, but if soldering leads is feasible, would the power of the gen2 mg2 in theory change with such a modification, changing leads in parallel instead of in series?


     
  12. bwilson4web

    bwilson4web BMW i3 and Model 3

    Joined:
    Nov 25, 2005
    27,068
    15,372
    0
    Location:
    Huntsville AL
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Plus
    Changing the internal stator wiring matches its load the NHW11 inverter that provides the voltage and current, the electrical power, to the modified MG2. The MG2 power is limited by the inverter electronics and traction battery.

    Bob Wilson
     
  13. shagpal

    shagpal Junior Member

    Joined:
    Feb 18, 2006
    19
    1
    0
    since such a hack would in theory yield no power gain, would their be a worthwhile gain in durability to consider?

     
  14. bwilson4web

    bwilson4web BMW i3 and Model 3

    Joined:
    Nov 25, 2005
    27,068
    15,372
    0
    Location:
    Huntsville AL
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Plus
    We do not know but can speculate:
    • The NHW11 MG1 has suffered a number of stator burn-outs.
      • One SAE paper found that air bubbles entrapped in the stator potting compound of Japanese super trains can support coronal discharges that make ozone. The ozone eats the potting compound, insulation, and fails the motor. The paper discussed detecting the coronal discharge signature, microwave frequencies found on the power leads, to detect the pending failure.
    • Toyota made a number of manufacturing improvements that improved the quality.
      • UT Battelle papers analyzed the NHW20 improvements including dynamic testing.
      • Toyota SAE papers discussing the differences between the models.
    • Replacement parts
      • ~54,000 NHW11s -> ~44,000 today
      • ~700,000 NHW20s -> potential MG2 sources from crashed ones
    Bob Wilson