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I Finally Understand Hybrid Regenerative Braking

Discussion in 'Gen 3 Prius Technical Discussion' started by twittel, Dec 23, 2010.

  1. cit1991

    cit1991 New Member

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    This was posted in the GenII forums a while back. Click to enlarge.
    [​IMG]
     
  2. The Electric Me

    The Electric Me Go Speed Go!

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    It's hopeless, video, charts, graphs....I think I have a better understanding behind the science of Willy Wonka's Chocolate Waterfall than the specific minutia of how regenerative braking works..
     
  3. richard schumacher

    richard schumacher shortbus driver

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    And we haven't even *started* talking firmware :_>

    Understand regenerative braking at a high level and be happy that it works.
     
  4. mmcdonal

    mmcdonal Active Member

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    I would like to submit that the damper plate between the synergy drive and the ICE, specifically the damper springs therein, is the culprit in the bucking start ups, that keep the ICE rocking until the systems get in phase.
     
  5. twittel

    twittel Senior Member

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    Someone posted that unburned fuel from a previous start and quick shutdown cycle could be the culprit. I like this theory better.
     
  6. spiff72

    spiff72 Member

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    That unburned fuel theory doesn't make much sense to me either.

    It seems like any unburned fuel would be burned up within a half second or so of ICE ignition. Might explain a split second of rough idle, but not the 5-10 seconds (or more) that I have seen in the videos. I haven't experienced it myself (knock on wood).
     
  7. spiff72

    spiff72 Member

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    Well - I had my first bucking start this morning. And I think I can attribute it to the fact that I was reading up on the warming up stages and I wanted to test out the "stage 1a" (I think) that is supposed to run from the initial start of the engine to about 50 seconds later. My car was in the garage for about 4-5 hours and I thought I would time it to see how long it took for a noticeable change in engine sound (when the ignition timing enters normal range). So I started the car, timed it (about 55 seconds), and then shut it down.

    When I started it this morning, it bucked for about 2-3 seconds and settled down. Maybe the unburned fuel theory does make some sense after all!