A200s is pre-order for the second 20, it’s probably going to be 480GBP with shipping. It can also handle 18s
If it’s 5:1 then it’s not direct drive. You might be thinking of a gear drive
Well there is that old potato to keep digging up true
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I did not do a build thread. I posted some info in intro thread some time ago: https://www.electric-skateboard.builders/t/new-member-introduce-yourself-here-tell-us-your-plan/216/814?u=blezalex It has links to github and some more pictures.
Thanks for pointer to The A200S VESC . Does it run the same VESC firmware? I need FOC and current control.
When you are asking if his own motor control firmware will be open source then the answer will be yes I think. That is what @Kug3lis wrote in the past.
So I guess it will be available for sure.
When comparing the drain to source on-resistance of the VESC 6 MOSFET (IRF7749) to the one of the FatBoy ESC (IRF7769) I expect a constant current output of the FatBoy around 33A with a heatsink like the VESC 6 has with no airflow at room temperature. (RDSon around 1.08 mOhm@80A/VGS=10V for IRF7749 and RDSon around 2.93 mOhm@80A/VGS=10V for IRF7769) Also notice that the given 18s (75.6V for a full LiPo) is to close to the 80V hardware limit for a save operation in my opinion, so when using regenerative braking I would not use more than 16s. (Same why the A200S save limit is 16s also)
So I would say the real constant power of the FatBoy HV ESC uncooled will be around 2kW. So a lot less than the 10kW target. 
But keep in mind that in our applications we don’t use constant wattage for several minutes.
I haven’t yet figured out or decided according to the licensing as libraries have own licenses which I need to follow…
@hexakopter where did I mentioned what MOSFET’s I am using? Also please don’t discuss about specs if you don’t even know what is going to be in the end 
In the tests with casing, I was running over 100A for a good amount of time without air flow it felt same as laptop charger or etc didn’t have thermometer at hand 
Plus where did you brought out 80V as hardware limit? Also if talking hardware limits VESC6 runs with 60V mosfets at 51V voltages so it has higher chance to fail than 100V mosfet at 76V
EDIT: 80V was mentioned as maximum working voltage (for the crazy people who likes to live on the edge) hardware limit voltage is higher than that
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Do make a build thread detailing the software portion of it! I would love to build one of these myself. The A200S definitely has FOC and current control. It should be compatible with the VESC tool, although I think custom firmware is a given.
There are pictures in this thread available were you can see that IRF7769 MOSFETs are used. I discussed about specs because I am also interested in a higher power/voltage VESC and some people were asking about the constant current your design will handle. So I just shared my calculations I did for myself looking at a picture showing a PCB with the labeling “FATboy HV ESC V1.0-Beta 18s 150A”. So I calculated what would be possible with this current design (“normal” aluminum case without airflow) and not the end product which maybe looks totally different. No offense.
When the same physics apply to you that apply to me then this is not possible. (“normal” aluminum case without airflow) 
The VESC 6 can handle around 55A constant current (constant is >15 minutes for me) and as I stated before it uses MOSFETs with a superior RDSon than what is used in your design. So there is no way you can push 100A constant current for 15 minutes with the FatBoy HV ESC. (“normal” aluminum case without airflow) You should also be aware that case temperature ≠ MOSFET temperature.
You are now saying that you did the tests with the FatBoy ESC yourself but a few posts back that your father living in an other country assembled the board. It would be nice when you (your father or you) can proof me wrong and do a video showing 100A constant current (“normal” aluminum case without airflow) for >15 minutes.
How is it possible to have a hardware limit voltage higher than 80V when using INA240 current amplifiers with a 80V limit? And before you ask again where you mentioned using them it is also noticeable from the pictures. 
So in my comparison spreadsheet the save operation of the FatBoy ESC is still at 16s max voltage.
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Oh boy… Please take your science back to your backyard Based on your science it’s impossible to dissipate (I^2 * Rds = 100 * 100 * 0.0028 = 28W) of heat, which is nothing with the full aluminium case compared to VESC6 “case”. Also with over 100A constant current not the MOSFETs are the problem but the power delivery is a much bigger problem.
You can’t compare only because some other device is not capable of doing anything else. that’s why we are going to sell this is esc with case only to provide enough cooling to run it at high currents.
I am not uploading any testing videos because it is not the final design and still modifications happening. Like now I am changing design of final board as it has some minor flaws.
Also, I am developing this ESC since last October, I have made many prototypes and etc, my father is assembling the final product so that’s why he is doing it.
Regarding INA240 you know that motors are not driven at bat voltage because of current limiting? I have tested it with even 21S using 7 x 3S my graphene packs and it was still functioning just bit warm so please keep your paper knowledge to yourself
P.S. I am building this for my own project to use with 18S as a proof of concept that it works
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Also no one talks about constant currents on ESC as there technically impossible without braking or blocking motor to make it consume same high amount of current for long amount of time. I was using nichrome wire as water heater to test out current handling of the phases. Later on we are going to build dyno stand for testing motors and drive trains to test out power capabilities and etc. So I will be able produce high loads on motors by simulating resistance, that’s why I am not talking about constant current handling yet, just maximum allowed.
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Pardon me if I read over this and missed it while skimming info. E-rpm limits?
Haven’t yet tried out, at the moment with vesc firmware it should be the same as VESC6. On my own firmware don’t know yet anything as it is still in development and code is not the best quality to do benchmarks.
P.S. If you looking for high rpm FOC, FOC is not really suitable for high kv motors… iirc fastest one I saw was like 20k rpm but it was using >200Mhz mcu or etc and still struggled.
E-RPM is mostly limited by MCU performance and software. How long does it take to calculate next step values in between steps. For high speed motors compators are needed to detect zero crossing of BEMF and etc…
To get faster performance, sometimes you can use lookup tables instead of calulating the floating-point numbers.
sometimes…
add a 32 core cpu to your system
It’s not the problem of cpu performance, adc, pwm they all have maximum speeds I mean yes you can build fucking monster with oscilloscope level ADC, external PWM generator which uses freaking LVDS connections 
But who will want to pay several K for speed controller to drive 60$ motor
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the day i have to much money
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If this turns out to be plug and play by simply inputting a few basic parameters and is dependable, you will be an e skate hero! Sign me up!
Why so humble?
I edited my post to be clear I talk about an uncooled aluminium enclosure like mentioned in my first post. So no airflow and sitting in room temperature. I also said that constant current for several minutes isn’t used in our application, but it is a good benchmark because it is easy to reproduce with different hardware at same conditions and it is not dependent from riding speed and mounting for an example. (different airflow) On my ESC I am also using 150A motor current without a problem, but not for several minutes and with good airflow cooling the case. So I never said 100A are not possible. Just not with your FETs, a normal aluminium case without airflow at room temperature and running it continuous for >15 minutes. Good luck with your project and I am out now.
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