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    Lightweight AWD Sportscar

    Re reading your post multiple times, a few questions. How is charging on destination chargers? For higher rates are you using multiple chargers? How was chademo handshake handled? At what rate was it able to charge? I just see chademo and ccs taking off. VW is building chargers that support...
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    Lightweight AWD Sportscar

    Pretty much only for charging, yeah. 50kW is still huge at 19kwh. Most “scenic” drives leaving from southeast Michigan are 150+miles. That puts my entire range right on the bottom edge of being useful without fast charge. Stopping in a nice downtown once for half an hour halfway through the trip...
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    Lightweight AWD Sportscar

    So I had a talk with my wife about the car not having a windshield. It looks like It will have a windshield after all. Something about bugs and not wanting to wear a helmet every time we take a trip in the car. On the motor side of things I might even be backing away from AWD just to simplify...
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    Lightweight AWD Sportscar

    Nice XTR! My hope is that the car will turn heads as much as a nice track day special 😉
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    40kW 350V Motor Controller

    I’m working on a small AWD (motor per wheel) sports car with an emphasis on aero efficiency and quick recharge time rather than outright battery capacity. This relies on DC fast charge stations (CCS or CHAdeMO.) CCS protocols rely on battery voltage greater than 200V and most CHAdeMO station...
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    Lightweight AWD Sportscar

    A big part part of that is the ground/wheel interaction. You have have to model in a rotating wheel that actually crashes through the ground which is complicated to model and mesh. Most cars don’t have any underbody shielding for one reason, it costs money! ICE cars don’t get nearly the...
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    Lightweight AWD Sportscar

    Just about a year on from my last post and near 0 progress! I’ve come to some new assumptions: one is on battery voltage. Orion BMS supports LTO, many cells in series and chademo. This opens the door to quick charge but it seems that most stations do not work with packs under 200V. That means...
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    Lightweight AWD Sportscar

    The motors are to increase the inductance each controller sees. With a 90mm stator for the same kv the inductance will be 1.5x less. It’s the same reason for the multiple controllers, higher mutual inductance for the same kv. Another thing the multiple controllers does is increase redundancy...
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    Lightweight AWD Sportscar

    Proactive suspension system have been around for a while. A number of them should be hitting the road in the next 5 years. It’ll be a huge boon to efficiency nuts as there won’t be energy loss due to damping. On a side note, I have been looking more and more to move the batteries rearward...
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    Lightweight AWD Sportscar

    I would like to avoid active systems as much as possible. Most tend to come with a hefty weight penalty and have a greater number of failure modes. However, I am intrigued by your system. Is it similar to an SM? I plan on make the body plug the old school way: using Masonite sections every 4”...
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    Lightweight AWD Sportscar

    I’m trying to be really open minded to what an electric car CAN be. Many of the trade offs that IC cars make simply don’t need to exist for an electric car. An update on the goals for the project; the Midwest and especially Michigan are having a record year for pothole damage. After driving my...
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    Lightweight AWD Sportscar

    A couple point for clarification: -not in wheel motors but rather one motor for each wheel with a driveshaft...the trade off in ride and handling aren’t worth the ease of packaging -I’m not necessarily going to reduce the rear track vs front track, however, narrowing the rear track won’t make...
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    Lightweight AWD Sportscar

    I played with narrowing the tracks, rear track more so than front. Drag area is now 0.22 m^2. That's a decrease of 21% from the previous test. I want to play with how much I can reduce drag for maximum range.
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    Lightweight AWD Sportscar

    Absolutely. Eventually if budget permits I would like to move to a direct drive motor. The biggest issue was just finding stator laminations (YASA, EVO, and EMRAX would be a significant portion of my budget) as it stands I’m just using a single stage reduction to the wheels. Each motor is good...
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    Lightweight AWD Sportscar

    GOOD NEWS! Stator losses are only about 50W per motor at 30m/s! (At least per the simulation) I suspect it will be a bit higher since the laminations are joined together via a stamped tab, shorting the stack. There will also be stator, bearing, windage, drivetrain, and controller losses to take...
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    Lightweight AWD Sportscar

    For the controller I’m looking at 3 MTI85W100GC similar to what you had posted in one of the threads. It would be nice to be able to buy MTI145WX100GD so I could actually make decent power though.
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    Lightweight AWD Sportscar

    I’ll be needing to make 8 controllers :lol: I’m hoping to develop a nice compact 25kW powerstage for the SMD controller for insane ebike and light motorcycle use. Once again I’m learning as I go with all of this :lol: To put the drag into perspective the first gen insight has a CdA of...
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    Lightweight AWD Sportscar

    The Stratos is pretty lovely..... Here is the latest iteration. The Cd now stands at 0.181. It would be great if these numbers were accurate! 4.5 KW aero-load at 30m/s! Now that the aero package is coming together I need to start on the motors to make sure I don't lose too much in iron losses...
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    Lightweight AWD Sportscar

    i have the CFD software working a little better now. I have been running non-stop simulations, iterating to get a lower Cd. So far I'm at 0.20 for the Cd and 1.54 m^2 frontal area. That gives a drag area of 0.307 m^2; ~the same drag area as a bicyclist with drops! That's about 7kw at 30m/s...
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    Lightweight AWD Sportscar

    I'm currently working on getting some more accurate CFD software to test ideas before I show the whole design. I thought I would leave this teaser here for you, though.
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    Lightweight AWD Sportscar

    Got the batteries and stators in tonight. Made a quick model of the center battery box/ frame and ran a torsional moment through it. It gets about 10k lb-ft/deg just with just the center frame and no passenger cell!
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    Lightweight AWD Sportscar

    Registration is pretty easy in Michigan. If I follow basic FMVSS guidelines I should have no problem. Insurance will be another story but I cross that bridge when I get to it. I do plan on using regen braking with the belt drive. LTO have an insane charge rate (8C) which translates to 152KW...
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    Lightweight AWD Sportscar

    I’ve just started on the design and development of my own personal project car. I have been a long time reader of these forums, constantly inspired by all the collaborative development that happens. Some background: By trade I am an automotive exterior designer. I work at a one of the big 3...
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