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Regenerative braking and conventional

Discussion in 'Gen 2 Prius Technical Discussion' started by Caleb302105, Nov 24, 2014.

  1. Caleb302105

    Caleb302105 Junior Member

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    Hello,
    I'm wondering if the amount of regenerative braking varies based upon brake pedal input or if brake regen is always at a set level and just engages when you release the gas pedal and then the conventional brakes take it from there when you depress the brake pedal.

    I had originally believed it was variable, in that when you depress the brake pedal further you obtain more brake regen.

    However, when I had some maintenance performed by Toyota one of the service reps alluded to the idea that the brake regen doesn't do nearly as much as I thought it did.

    I would just appreciate it if someone would clear this up for me by explaining or referring me to another blog post etc.

    Thank you everyone for your time and replies.
     
  2. bisco

    bisco cookie crumbler

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    varies. on the gen III they have a gauge called the hsi, hybrid system indicator, which shows you the amount of regen in a sliding bar graph. it move a little when you let off the gas, and more and more as you press harder on the brake until the friction brakes kick in.
     
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  3. Patrick Wong

    Patrick Wong DIY Enthusiast

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    The amount of brake regen is definitely variable based upon brake pedal input. This is documented in the Toyota New Car Features Manual (available on techinfo.toyota.com) which contains a chart that shows the proportion of brake regen and friction braking as a function of brake pedal input.

    If you think about it, it would make no sense for brake regen to be at a set level. You may need to brake the car at a very gentle rate, you may need to brake the car at a faster rate, or you may need to make a panic stop. If the regen was always at a set level, a tremendous proportion of braking effort would have to be performed by the friction brakes and therefore the benefit of regen braking would mostly be lost.

    With the Toyota design, regen braking plays a major role in any braking activity except when you make a panic stop - in that instance friction braking provides substantially all of the braking effort.
     
    #3 Patrick Wong, Nov 24, 2014
    Last edited: Nov 24, 2014
  4. uart

    uart Senior Member

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    Which in turn alludes to the idea that some of the service reps don't know nearly as much about the Prius as we thought they did. :D
     
  5. Caleb302105

    Caleb302105 Junior Member

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    Alright, thank you everyone for your prompt replies. I had hoped that was the case.