Register To Comment
Page 1 of 10 123 ... LastLast
Results 1 to 10 of 95

Thread: 300A VESC in the works, feature suggestions wanted

  1. #1
    TechAUmNu's Avatar
    Roboteer

    Status
    Offline
    Name
    Euan Mutch
    Robots
    Triforce(HW) (in progress) A450S (ESC) (in progress)
    Location
    Edinburgh, UK
    Posts
    176
    Post Thanks / Like
    I am working on designing a 16s 450A VESC. Called the A450S.

    Estimated Pricing as of 23rd Aug 2017:
    £350 for bullet connectors,
    £400 for lasercut lugs.
    Repairs cost the price of parts and shipping.

    In comparison a 15s 400A MGM controller costs £800!

    So far I have chosen to use OptiMOS fets and TI 4A discrete gate drivers.
    FETs: FDBL86361_F085
    Gate Drivers: UCC27211A-Q1

    The first version will have:
    • 6 Fets per phase leg (36 total)
    • 6 Gate drivers per phase (18 total)
    • Aluminium base cooling plate with threaded holes for options:
    • -- Finned aluminium heatsink for open air running with option for fan should allow continuous running at 450A
    • -- large block of aluminium for heatsoak in bots with no airflow should allow running for up to 5min at 450A
    • Unit comes as two boards linked by a short cable, this lets you put all the control boards closer to your receiver and keep everything away from the high power components to reduce noise.
    • STM32f405 Cortex M4F
    • 4x Nichicon PW(M) bulk capacitors
    • 3.3V, 5V and 12V TVS diodes on rails to protect cpu and driver chips. I would like to also have one to protect the mosfets and current shunt amps, but TVS diodes need quite a large range before they begin conducting which would limit the maximum voltage to about 12s.
    • 16s LiPo maximum (Rating at 80v on the mosfets and current shunt amps, so need a bit of margin to account for ringing/transients especially with no TVS diode on main supply)
    • 450A continuous
    • 1200A burst
    • Axial connectors (Everything inline to make them stackable, this is only possible with bullet connectors)
    • All standard VESC features (CAN, SPI, Encoder/Hall support)
    • Same amazing VESC performance with sensorless motors.
    • Lots of free space around mounting points for shock mounts (can be provided if required)
    • 40W nominal power dissipation at 300A (Continuous for 10min before performance degradation)
    • 90W nominal power dissipation at 450A (Continuous for 4min before performance degradation)
    • Designed specifically for combat use. Absolutely no heavy components on the boards which might fall off with shock. (A perfect companion for Neumotors or other 10kW+ motors)
    • Each unit is hand built and will be rigorously tested before sale using a range of motors. (100W, 2200w, 5300w, 15000W) If I have the motor you will be using then I can set it up for you before sending it.


    Progress so far:
    • Power stage components chosen
    • Power stage schematic complete
    • Logic side schematic complete
    • Power dissipation calculations complete
    • Power supply selection complete
    • Buck converter design complete
    • Switched gate drivers to UCC27211A-Q1
    • power stage rework complete
    • Switched MOSFETS to FDBL86361_F085 to reduce cost and power dissipation
    • Power board layout complete
    • Power board ordering complete
    • Logic board layout complete
    • Logic board ordering complete
    • Power board testing in progress...
    • Logic boards shipped
    • Power board design v2 in progress...


    This thing is overkill in every way possible. Hopefully that makes it very reliable in the arena.
    Last edited by TechAUmNu; 25th August 2017 at 09:58.

  2. #2
    typhoon_driver's Avatar
    Member

    Status
    Offline
    Name
    Gary Cairns
    Robots
    Hornet 2 - retired Boner - retired Smidsy - Sold 540 - Sold PP3D - Active
    Location
    Aberdeenshire
    Posts
    4,372
    Post Thanks / Like
    Features - cost less than a tenner. You'll be very popular

  3. #3
    overkill's Avatar
    Member

    Status
    Offline
    Name
    Nick Martin
    Robots
    Mr Mangle - Australian 2015 Featherweight Champion 2016 UK Gladiator Shiny Scissorhands Decimator
    Location
    Sydney Australia
    Posts
    875
    Post Thanks / Like
    A potted case is a REALLY bad idea! I tried that on a number of IFI Victors a few years ago and they all eventually died. It was traced back to the potting resin expanding at a different rate to the PCB and causing solder joints to crack. A thin conformal coating is a better bet. Room to add our own shock mounts is a good idea.

  4. #4
    TechAUmNu's Avatar
    Roboteer

    Status
    Offline
    Name
    Euan Mutch
    Robots
    Triforce(HW) (in progress) A450S (ESC) (in progress)
    Location
    Edinburgh, UK
    Posts
    176
    Post Thanks / Like
    Quote Originally Posted by overkill View Post
    A potted case is a REALLY bad idea! I tried that on a number of IFI Victors a few years ago and they all eventually died. It was traced back to the potting resin expanding at a different rate to the PCB and causing solder joints to crack. A thin conformal coating is a better bet. Room to add our own shock mounts is a good idea.
    Good to know! Its probably best to not have any coating then to make it easier to replace parts.

    As for pricing I don't want it to be over £300 current BOM is ~£120 + board.

  5. #5
    Roboteer

    Status
    Offline
    Name
    N/A
    Robots
    The Unnamed, Bourbon, Deadlock
    Location
    UK
    Posts
    125
    Post Thanks / Like
    There's a couple of us trying to build 300A ESCs now.

    Personally I'm not a fan of directFETs, can't inspect joints, package is unique to Infineon and they seem to discontinue them quickly. HSOF packages seem much better to me, it's what they use in the Vex BB controllers.

  6. #6
    Roboteer

    Status
    Offline
    Name
    Chris
    Robots
    Spur 2, TCOB, Olaf
    Posts
    504
    Post Thanks / Like
    Not sure on the integrated shock mounts. Prefer some flexibility on mounting e.g. mount into a shock mounted electronics box

    I'm looking to drive 8019 Neumotors - http://neumotors.com/80xx-series-electric-motors/

  7. #7
    TechAUmNu's Avatar
    Roboteer

    Status
    Offline
    Name
    Euan Mutch
    Robots
    Triforce(HW) (in progress) A450S (ESC) (in progress)
    Location
    Edinburgh, UK
    Posts
    176
    Post Thanks / Like
    Quote Originally Posted by shakesc View Post
    Not sure on the integrated shock mounts. Prefer some flexibility on mounting e.g. mount into a shock mounted electronics box

    I'm looking to drive 8019 Neumotors - http://neumotors.com/80xx-series-electric-motors/
    I will make the mounting points on the board with plenty of room around them instead, then it gives people mounting flexibility.

    So about 350A peak on those motors, I might end up making another board with 6 or 8 fets per phase if there is demand. It really bumps the price up though.

  8. #8
    TechAUmNu's Avatar
    Roboteer

    Status
    Offline
    Name
    Euan Mutch
    Robots
    Triforce(HW) (in progress) A450S (ESC) (in progress)
    Location
    Edinburgh, UK
    Posts
    176
    Post Thanks / Like
    Quote Originally Posted by Pinski1 View Post
    There's a couple of us trying to build 300A ESCs now.

    Personally I'm not a fan of directFETs, can't inspect joints, package is unique to Infineon and they seem to discontinue them quickly. HSOF packages seem much better to me, it's what they use in the Vex BB controllers.
    I was thinking that too, only real reason I was going with them was for the ability to stick a heatsink directly onto them, but looking at the HSOF I am going to use this one instead.
    http://www.mouser.com/ds/2/196/Infin...-en-767648.pdf
    Has almost half the on resistance and bumps the current rating way up for a very small price increase.

    Thanks!

  9. #9
    TechAUmNu's Avatar
    Roboteer

    Status
    Offline
    Name
    Euan Mutch
    Robots
    Triforce(HW) (in progress) A450S (ESC) (in progress)
    Location
    Edinburgh, UK
    Posts
    176
    Post Thanks / Like
    Would people prefer it to be

    A) Smaller with no 5v Dc-DC. i.e. OPTO
    B) Larger with integrated 5v Dc-Dc about 2A (also makes it £10-20 more expensive)

    I think its best to be OPTO since people will likely already have a 5v dc-dc and if they don't they can easily add one.

  10. #10
    Roboteer

    Status
    Offline
    Name
    Chris
    Robots
    Spur 2, TCOB, Olaf
    Posts
    504
    Post Thanks / Like
    My vote would be OPTO

Register To Comment

Posting Permissions

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