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  1. S

    Axiom: a 100kW+ motor controller

    Have you had any beta testers successfully integrate an Axiom board with unique inverter electronics? I've been messing with some hybrid vehicle inverters and getting my feet wet with Axiom for the price of the control board and some time learning to interface it to a Prius seems like a good and...
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    Yasa/Makani controller teardown

    Serious piece of kit there. I'd be interested to see what an Axiom with 1200V switches could do with it - last I read the control board isolation was good for 800V bus. Are the spinning cases integrated into the motor or is there a shaft behind them? The example motor you linked is an in-runner...
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    APL's DIY axial-flux motor

    Congrats! I look forward to seeing it mounted on a bike! :D
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    Converting Derbi Senda to electric

    It could be for a magnet on a shaft or wheel to do revolution counting. If you connected it to the phase output and it wasn't up to the voltage it may have broken that particular sensor. Measure the point with a multimeter when it's not connected to anything. If it's at logic high it probably...
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    Open source BMS for 48V to 400V lithium-ion battery pack

    This is a very cool project, and I have some ideas that this will be perfect for. In the short term, the SS looks like just the ticket for my smaller e-bike projects. Does the ENNOID-BMS-SS work without enabling or installing the main MOSFET/Contactor? I have a project right now that could use...
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    Neu 8057 6kW left hand drive hardtail with vesc and encoder

    Very cool! Is the field weakening firmware based on the Power Designs experimental branch of the VESC firmware?
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    Small electric car self build

    The QS 138 70H is a popular choice and those who use it say it's very torquey. As torque is a product of current, any appropriate controller that runs on 48V should be able to max out its torque potential just fine. It will just run at a proportionately lower power/rpm than at it's rated 72V...
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    VESC based +200A powerstage with 200V MOSFETs (videos of it in action)

    I've been thinking about this on and off and after a little digging, found a thermal conductivity figure for Kapton of .12W/m*K. Inexpensive thermal pad I've seen around has a conductivity of 1-2W/mK. Based on these numbers, a .5-1mm thick piece of ordinary silicon thermal pad has the same...
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    What is the optimum build for a long range light motorbike/ebike?

    Believe it. If you don't believe me, ask around with some of the folks with higher speed bikes how many Wh it takes to go a kilometer at different speeds. Air resistance above a shockingly low speed - the rule of thumb appears to be 25mph/40kph - becomes the dominating system loss. If you don't...
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    Opinions please: VESC - Vedder Electronic Speed Controllers

    I've read bits and pieces of the InstaSpin documentation, and I think there's support for overmodulation built into it. How much faster that would make a motor spin I don't know, but it might account for what you're talking about.
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    What is the optimum build for a long range light motorbike/ebike?

    I think you're confusing energy per speed and energy per distance. It takes more energy for unit distance to go faster due to the poor aerodynamics that you will get on any motorcycle unless it is completely covered in a fairing or shell. 25Wh/km is the energy usage per kilometer at low speed -...
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    Axiom: a 100kW+ motor controller

    That's good to know too, but I can't figure out how to acquire one, as much as trying to specify one. It's not listed in the BOM on the Hackaday blog or anywhere else that I've been able to find.
  13. S

    Axiom: a 100kW+ motor controller

    Out of curiosity, how does Axiom get the cold plates specified for operation? This is one of the obvious (to me) advantages of buying a pre-built Axiom, but I can think of other uses of the manufacturer's cold plates as well.
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    Cheap FOCer 2 (Open-source, Low-cost, VESC 6 based ESC) (v0.9 release! Beta testing still ongoing)

    So I've had a couple DRVs fail (not unexpected with my messing around), but I seem to be having the issue that when I reach 40ish amps phase @50% duty that my DRVs throw faults. As in all the faults. My test motor is a mid-monster that I'm running as a self-contained dyno to test the Cheap...
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    Cheap FOCer 2 (Open-source, Low-cost, VESC 6 based ESC) (v0.9 release! Beta testing still ongoing)

    Thanks for the offer, Amberwolf, but unfortunately the meter would be cheaper than a trip to meet you. Much appreciated!
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    Astro Flight motor on cargo bike

    If you want an American made motor, check out the Neu 8057 based builds on Endless Sphere. They spin slowly enough to work with a single stage reduction and can put out lots of power. Neu is also offering 120 and 180 size motors as well.
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    Cheap FOCer 2 (Open-source, Low-cost, VESC 6 based ESC) (v0.9 release! Beta testing still ongoing)

    I tried it at 50kHz, but it didn't appear to affect motor heating at all. I suspect that the resistance and inductance measurements are probably not accurate, but I don't have the test equipment to measure these outside of the VESC software. One of these days I'll get a DE-5000 LCR meter, but...
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    Cheap FOCer 2 (Open-source, Low-cost, VESC 6 based ESC) (v0.9 release! Beta testing still ongoing)

    Bought my first batch and freshly assembled these FOCers. With some moving and life, a bunch of stuff has gone missing, but I found some old Leopard boating inrunners I pulled out of some junked boats a while ago. My first thought was that they're too low inductance and I shouldn't bother, but...
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    VESC based +200A powerstage with 200V MOSFETs (videos of it in action)

    I was curious what the junction temps of your tests were, so I did my best to back them out of the datasheet and your numbers. Figured I'd share since I'd already done the work. Based on your comments about runaway, they're unsurprisingly above 100C. The numbers for the single layer of kapton...
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    VESC based +200A powerstage with 200V MOSFETs (videos of it in action)

    Thanks for sharing, I've learned a great deal reading your posts about inverter and gate driver design, and I'm hoping to try out what I've learned from you for myself in the near future. It's really cool to see your bus and thermal layout considerations, and a great learning experience for a...
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    Electric Scooter Conversion - Polish WFM Osa M52

    The nice thing about electric is you can always just turn your controller down and instantly have a more reasonable power level if you find yourself with too much power. Electric motors will only complain about being over powered, not under powered. "Nucular" refers to Vasili's line of motor...
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    Electric Scooter Conversion - Polish WFM Osa M52

    Many modern speedos use very small stepper motors to actuate the needles, and these motors are available for personal projects. It depends on how comfortable you are with programming and taking apart the old cluster as to how hard that would be. I don't know if there's any open source projects...
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    Cheap FOCer 2 (Open-source, Low-cost, VESC 6 based ESC) (v0.9 release! Beta testing still ongoing)

    Somewhere in Vedder's testing videos he has pictures of a turnigy outrunner testing underwater. Distilled and deionized water is inexpensive from the grocery store, so it wouldn't be difficult to swap out water. And as Marcos pointed out, it's not terribly conductive anyway. Best way to remove...
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    Suzuki GSX-R e899 K2

    My best answer is I don't know. Arlo has mentioned some lightweight race cells in his CRX build thread. But if you have a set of batteries on hand that you can run the motor on, even if it's a much lower voltage than you want, you can get some good data from running as-is. 1.5 milliohms per cell...
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    Suzuki GSX-R e899 K2

    Once you know the no-load current draw at low and high RPM, this can be refined for eddy and hysteresis torques, and of course it assumes no field-weakening (is your motor IPM?), but something for you to mess around a bit with for your bike. I assumed 196 cells charged to 4.1V @ 5Ah and guessed...
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