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PiP Regen Behavior?

Discussion in 'Gen 1 Prius Plug-in 2012-2015' started by Redpoint5, Feb 14, 2016.

  1. bisco

    bisco cookie crumbler

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    yes, well, there might be a max safety, i don't think toyota has it in the manual. neutral is illegal here if the car is moving.
    i don't think i was clear though. if i put it in neutral going down the hill, and back in drive as i'm going back up, i can defeat the engine coming on.
    but if i have traffic behind me, i have to go 40 mph, and the engine is going to come on anyway. putting it in neutral won't help unless i can stay under 34 or so, until i've burned off a few ev miles. then i'm good after that.
    i don't know if the parameters change as the battery empties, or because the batteries are warmer from use. or both.
     
  2. Redpoint5

    Redpoint5 Senior Member

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    I think I read that neutral is not a mechanical disconnect of the drive train, so MG1 still ends up spinning. The max safe speed for MG1 is something like 82 MPH, so I don't think it's ok to exceed that speed in neutral.
     
  3. QuantumFireball

    QuantumFireball Active Member

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    What kind of speeds are you doing when you experience this behaviour of the ICE coming on during long regen periods? I notice Nougatti is going around 75-80 km/h in that video. Could there be a lower RPM limit for MG2 going in reverse? Or is it happening when the battery is reaching a certain SOC? Looks like maybe about 50-60% in the video (assuming full on the meter is 85%).
     
  4. Nougatti

    Nougatti Member

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    Though it's being used as a generator and not a motor, I assume it's still spinning in the same directions as when you drive it and not in reverse.
    I've had lower SOC on the same hill with the same result.

    I assume the MG1 isn't disconnected at 82 MPH either, so if you're going past those speeds, flat out, the MG is still having to spin along.
     
  5. Redpoint5

    Redpoint5 Senior Member

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    I don't think so. Somehow the way the engine, MG1, MG2, and planetary gearset are put together, the speed of the vehicle can be varied while holding the speed of either the engine, MG1, or MG2 at a constant.

     
  6. QuantumFireball

    QuantumFireball Active Member

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    Oh yeah, that makes a lot more sense...
     
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