Power in Flux
Likes Likes:  10
Page 1 of 12 12311 ... LastLast
Results 1 to 10 of 118

Thread: EnerTrac 600 series In wheel Motor

              
   
   
  1. #1
    Senior Member markcycle's Avatar
    Join Date
    Aug 2010
    Location
    Long Island, NY
    Posts
    240
    Post Thanks / Like

    EnerTrac 600 series In wheel Motor

    Just wanted to get this started not sure if I should rehash the old forum or just move forward. One thing I did was to start a blog and will try to keep important information there, So if I answer a question that i feel will be of general interest I'll re-post it there.
    http://enertracrawfeed.blogspot.com/
    I'll exchange information and I'll show and others will show there builds but if you have a sales question please PM me this is not a sales thread.
    Last edited by markcycle; 21 August 2010 at 1726. Reason: grammar
    Trying to Change the old school ways of doing things
    But I never Never try to break the laws of Physics
    http://www.enertrac.net
    http://www.evalbum.com/preview.php?vid=1543
    http://www.youtube.com/watch?v=nEldNmBgIF0
    http://www.evalbum.com/2568

  2. #2
    Senior Member markcycle's Avatar
    Join Date
    Aug 2010
    Location
    Long Island, NY
    Posts
    240
    Post Thanks / Like

    Converting a two turn winding to a two or four turn winding

    Four turn for better low end torque and efficiency at 30 MPH switch to a two turn winding for high speed is the concept.
    http://enertracrawfeed.blogspot.com/...on-part-2.html
    Trying to Change the old school ways of doing things
    But I never Never try to break the laws of Physics
    http://www.enertrac.net
    http://www.evalbum.com/preview.php?vid=1543
    http://www.youtube.com/watch?v=nEldNmBgIF0
    http://www.evalbum.com/2568

  3. #3
    Senior Member markcycle's Avatar
    Join Date
    Aug 2010
    Location
    Long Island, NY
    Posts
    240
    Post Thanks / Like

    E-transmission part 2 testing begins

    We got the bike back on the road and I did the first test ride and the results are interesting.
    The goals of this experiment were two fold

    1. The main goal was to better match the C rate of the batteries to the motor, reducing locked rotor amps. Essentially impedance matching the motor to the batteries, without question this goal was achieved. What this means is from a standstill to about 30 MPH half the current is needed when in 604 mode to achieve the same torque as a 602 two turn motor. Then at 30 MPH I drop the throttle flip a switch and continue in 602 mode. The controller has no problems with the switch from four turn to two turn and back again.
    2. The second goal was more of a hopeful goal being even better performance, this is yet to be obtained. Electric motors are interesting animals and very different than there ICE counterparts. While a ICE engine build power with RPM electric engines have most of their torque at the low end of the RPM range. I was Reving out the 604 mode before switching to the 602 mode and from 20 MPH to 30 the performance dropped as the motor became voltage starved. To really test performance I should have switch out of the 604 into the 602 much earlier. To do this fast enough to realize a performance benefit shifting really has to be fast and probably automatic. I believe there is performance to be had as long as no time is wasted shifting. With 100 volts of battery the max top speed in four turn mode is 35 MPH

    Conclusion:
    Actively switching from a four turn motor to a two turn motor works and results in a reduced starting current off the line. An active impedance matched motor reduces the peak current demand on the batteries allowing a peak of 2.5C instead of 5C for the same performance one would get with the standard 602 two turn motor. Also there is less controller switching and less high order harmonics wasting heat in the motor. Performance gains have yet to be measured.

    full story at
    http://enertracrawfeed.blogspot.com/
    Trying to Change the old school ways of doing things
    But I never Never try to break the laws of Physics
    http://www.enertrac.net
    http://www.evalbum.com/preview.php?vid=1543
    http://www.youtube.com/watch?v=nEldNmBgIF0
    http://www.evalbum.com/2568

  4. #4
    Moderator Nuts & Volts's Avatar
    Join Date
    Aug 2010
    Location
    Columbus, OH
    Posts
    1,766
    Post Thanks / Like
    Is this similiar to delta/wye switching a brushless motor? It sounds like it, but i am still learning this stuff. So by starting with 4 turns you achieve the same torque with less amps (gaining efficiency from your motor and your batteries), then you switch over to 2 turns and turn the extra torque into increased rpm.

    Essentially you are changing the kV of the more by a factor of 2?

    This is really cool project.
    Kyle
    Whats under my tank may shock you!!! R6 Build, Blog/, [/URL] OSU Current webpage

  5. #5
    Senior Member markcycle's Avatar
    Join Date
    Aug 2010
    Location
    Long Island, NY
    Posts
    240
    Post Thanks / Like
    That's right I'm changing the Kv of the motor as you said by a factor of 2. In truth, I would have preferred Wye/Delta but the motor is designed for a trapezoidal waveform to minimize cogging, this design will not work in Delta. Yes by being in four turn mode you achieve the same torque at half the amps, the sacrifice is speed of course. The real benefit is on the battery side the gains in the motor are small. But reducing the peak amps, C rate needed from the batteries during starting from a stop is huge. It means you can get really good performance from smaller low C rate batteries like the 40AH thundersky's I'm using without destroying them.

    Mark
    Trying to Change the old school ways of doing things
    But I never Never try to break the laws of Physics
    http://www.enertrac.net
    http://www.evalbum.com/preview.php?vid=1543
    http://www.youtube.com/watch?v=nEldNmBgIF0
    http://www.evalbum.com/2568

  6. #6
    Member soyachips's Avatar
    Join Date
    Aug 2010
    Location
    Sydney, Australia
    Posts
    88
    Post Thanks / Like
    I agree, very cool project. Is the automatic shifting going to be possible?

  7. #7
    Senior Member markcycle's Avatar
    Join Date
    Aug 2010
    Location
    Long Island, NY
    Posts
    240
    Post Thanks / Like
    Quote Originally Posted by soyachips View Post
    I agree, very cool project. Is the automatic shifting going to be possible?
    It will be its not that hard to do

    Mark
    Trying to Change the old school ways of doing things
    But I never Never try to break the laws of Physics
    http://www.enertrac.net
    http://www.evalbum.com/preview.php?vid=1543
    http://www.youtube.com/watch?v=nEldNmBgIF0
    http://www.evalbum.com/2568

  8. #8
    Senior Member markcycle's Avatar
    Join Date
    Aug 2010
    Location
    Long Island, NY
    Posts
    240
    Post Thanks / Like

    Enertrac Gets on the dirt

    This is our first trip to the motorcross track and the first ride


    Hub motors can ride the dirt

    Mark
    Trying to Change the old school ways of doing things
    But I never Never try to break the laws of Physics
    http://www.enertrac.net
    http://www.evalbum.com/preview.php?vid=1543
    http://www.youtube.com/watch?v=nEldNmBgIF0
    http://www.evalbum.com/2568

  9. #9
    Only2Jakes
    Guest
    That's awesome!
    You can tell it's much lighter than the other bikes because it's just jumping around, or this could be the torque!! Still, Well done!

  10. #10
    teddillard
    Guest
    Very cool!

    That brings up a whole ton of questions about the hub motors- it certainly makes sense to run a hub on a trail/MX bike because of the small frames and limited battery space- but what about the unsprung weight? It seems like a hub on a street bike on a paved road would not have too much effect, but on a trail or dirt track, it seems like you'd really see the difference.

    Has anyone run comparisons? I'd love to see an independent evaluation by a good rider- maybe a Quantya, Zero and a hub bike... (wish I was good enough myself to do it, but those days are loooooong gone for me!)
    Last edited by teddillard; 27 September 2010 at 0429.

Page 1 of 12 12311 ... LastLast

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •