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    Want to move away from Proprietary to Mainstream

    The nice part about going down that road is that once you're done you not only have a system that you truly understand but also future projects either go a lot easier or get correspondingly more ambitious.
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    Can you Charge a 60 or 72V Battery Pack with "a" 12V Solar Panel?

    You absolutely can; it's just going to require a DC/DC converter and an MPPT controller between the panel and the battery charge input. The MPPT controller essentially adjusts the duty cycle (and thus the input impedance of the converter) to match the voltage and current that gets the maximum...
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    Sondors up for sale

    Just read the Electrek article and this looks like an utter mess (also makes me wonder whether what he was building was ever actually deliverable for the prices he was promising; like if I'm remembering correctly this was also the $500 fat tire ebike guy who didn't really have much in the way of...
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    Some thoughts on the future of automotive EVs

    I mean for me it's more of a personal thing; like I currently drive a manual car and (even though I know it sounds silly) I feel significantly more connected to the vehicle with a manual transmission than with automatics and CVTs I've driven; 250-300kW (comprised of 150-200kW engine output with...
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    Wind and Solar vs Coal, Gasoline, Nuclear

    Ahhh gotcha :) I was East Campus and then Pika during my time at MIT :)
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    Some thoughts on the future of automotive EVs

    Honestly same; tbh if I could buy a PHEV with AWD and a manual transmission I'd just do that for the foreseeable future, and then move to a full EV later if/when I end up owning a home with a place to stash and charge it. Like my ideal for an EV would be something like a kei truck/bakfiets with...
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    Wind and Solar vs Coal, Gasoline, Nuclear

    Agreed! Nuclear for 24/7 baseload, wind and solar plus storage for everything else :) Just out of curiosity, did/do you go to MIT and live on 5E at East Campus?
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    Free energy machine

    This patent looks like some sort of weird self-driven magnetic pendulum, and there's no way that it's actually generating any energy.
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    Wind and Solar vs Coal, Gasoline, Nuclear

    I mean, solar and wind by themselves are amazing but need energy storage solutions (whether that's pumped hydro, some sort of closed-loop hydrogen thing, batteries, or a combination of the three) to be able to act as a grid backbone, and honestly our grid would probably work better and be more...
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    Design/Build a flyback converter

    Yup! TI has a reference design for a four-output fly-buck that they use to drive an IGBT half-bridge that I'm looking at for work: https://www.ti.com/lit/ug/tidu478/tidu478.pdf?ts=1704894200364&ref_url=https%253A%252F%252Fwww.google.com%252F The nice bit is that the transformer is an off the...
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    Design/Build a flyback converter

    Yeah; the space I mostly see them used in is for low-power low-component-count isolated power supply designs for things like IGBT drivers (where the peak switching currents may be quite high but the average current draw is quite low). and very small (<20W) off-line converters for electronics...
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    Rough draft of a 6FET power stage intended to be part of a larger controller

    Right; the Zynq part has a physical CPU that shares a portion of its memory fabric with the FPGA; if I have room for a fast softcore CPU and all the custom hardware I'd need for fast motor control on something smaller and cheaper like the Artix or Spartan then I could save money on the part in...
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    Rough draft of a 6FET power stage intended to be part of a larger controller

    That's fair; the current Xilinx parts are unfortunately all BGA (though the older Spartan 3s are about 30 and come in 144-TQFP packages. I'd probably develop on the Zynq part and get everything optimized, and once I figure out how much space I need for fast hardware, I'd try porting over to a...
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    Rough draft of a 6FET power stage intended to be part of a larger controller

    The answer there is to use an FPGA for control instead of an MCU. It bumps the price up significantly, but if you use one of these you can use the onboard CPU for CAN communication, ABS, and other things that need millisecond response times, but implement the motor control itself directly in...
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    Rough draft of a 6FET power stage intended to be part of a larger controller

    Honestly, my benchmark for the power levels I'm looking to eventually handle is an Emrax 188 or 208 LV; they're amazingly light (~20-22lbs for 68kW peak, 41 kW continuous), but in the low voltage version they claim ~7-7.5uH inductance, which is going to require fast switching and a fast control...
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    Rough draft of a 6FET power stage intended to be part of a larger controller

    Thanks! I'm going to try to take a second cut at it over the week next week and will post the new layout up here hopefully by sometime next weekend :) I look to fast switching as a way to maximize controller efficiency, and at reasonably high switching frequencies like the ones I'm used to...
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    Rough draft of a 6FET power stage intended to be part of a larger controller

    Thanks for the advice! If you don't mind my asking, what changes would I need to make the layout functional for 100A at 50-100kHz?
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    Rough draft of a 6FET power stage intended to be part of a larger controller

    On the 6-FET board above, at 100kHz, if I use this datasheet to derive an approximate switching time, the AOTL66518 would have a switching time of 12ns or so at 4A, and so the overall switching loss would be about 8.8W per device at 100kHz, while conduction losses assuming datasheet Rdson would...
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    Rough draft of a 6FET power stage intended to be part of a larger controller

    They're right on DigiKey: https://www.digikey.com/en/products/detail/alpha-omega-semiconductor-inc/AOTL66518/12823097 The datasheet says 150V 214A; I'm assuming that I can get away with 150V 100A if I use copper busbar to pull the current out of the center node and to buttress the current...
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    Rough draft of a 6FET power stage intended to be part of a larger controller

    I couldn't sleep and so I took a whack at designing a power board for a fairly large motor controller. The board itself is a 6FET power board; the idea would be to parallel several of them to create a 150V, 400- to 600A-capable controller. The board takes in a differential PWM signal and...
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    Non-silicon and/or soft-switched controller topologies?

    It's a clever idea; I haven't really delved into the design of ARCP inverters so I'm not sure; the stuff I saw talked about high circulating currents in the resonant leg; my best guess is that the AI is mostly timing the resonant leg commutation as needed to drive the circulating current to the...
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    Reverse eTrike Primarily For Snow/Ice As Well As All Season

    I used that trike with a Bafang for winter commuting this past winter (~9.5 miles each way) and it worked great on icy trails but not so hot on roads, or when the trails were covered in snow that had been walked in and refrozen. Honestly for what you're looking for, if you're up to it and have...
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    Non-silicon and/or soft-switched controller topologies?

    Yeah, looking at the SVPWM paper I found it looks like SVPWM does the same thing as THD, and for what I'm trying to do I'll take SVPWM (paper reference here) My next goal is to write a CORDIC module that can do the angle rotation serially (which would likely take 33-35 clock cycles to do at...
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    Non-silicon and/or soft-switched controller topologies?

    This is where I think doing the whole thing on the FPGA gives me an edge; I can create extra CORDIC modules, and if I do it right I can get them completing in 30-40 clock cycles, which means that I can probably make this work given the 700ish MHz internal clock on the FPGA. If I'm understanding...
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    Non-silicon and/or soft-switched controller topologies?

    Ahhhhh, that makes a lot of sense; my initial thought process was to take the inverse Park output, put it in mag/phase form, vector-add a small component at 3x the angle, and then use that vector to drive the SVPWM setup, but that may not work so well depending on the motor back-EMF shape and...
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