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DRV8301-HC-C2-KIT

Jimbo5760
Intellectual 490 points

Other Parts Discussed in Thread: CONTROLSUITE, INSTASPIN-BLDC

Hi all,

For a school project I'll be involved in designing an E-board and we're having a hard time figuring out if this development kit has what we need. The voltage and current ratings are perfect but we need precise control of a BLDC motor. I've been reading all about the InstaSPIN technology and seems like we need to use the FAST and/or MOTION software provided with C2000 Piccolo chips. The problem we're having is getting a clear answer with whether or not the F28035 C2000 Piccolo provided with this kit  will have access to all of the software that we need. If not, can we order that motor driver development board with a different Piccolo control card? Or does the software provided with the F28035 give us what we need? The language seems to say it does but don't want to drop $300 without knowing for sure!

Cheers,

Jim

  • 0
    Guru 117855 points

    Jimbo5760 said:
    The problem we're having is getting a clear answer ...

    Speaking to the desire for, "clarity" might you (somewhat) detail your definition of, "precise control of a BLDC motor?"   (i.e. speed/current control/regulation, position, accel/decel rates, performance under hard braking, etc.)    (hate it when what's sought - is itself - violated...)

  • 0 in reply to cb1_mobile
    Intellectual 490 points
    Hi cb1_mobile, thanks for the response! So all speeds/accelerations will be based upon the throttle position. Max throttle will give max acceleration, min throttle will give min acceleration. Deceleration rates will be achieved through regenerative braking/plugging when the batteries are full and as such full braking likely won't be required since we don't want to be thrown off the board. Acc/Dec rates will be an area that will be calibrated to ensure comfortable riding. I guess position will be important so that the motor doesn't have a jittery response during operation. That's the kind of function that our BLDC motor will have.
  • 0 in reply to Jimbo5760
    Guru 117855 points

    Thank you.    Please accept that while you've provided "far more detail" - the need, clear definition (and support for) "precision" remains absent.

    Not to, "break your chops" - but might KISS enter your consideration - so that you may gain (some) real-world motor/control experience - and (only then) state w/some clarity - your, "precise specifications?"

    Wealth of posts appear here - suspect a concerted (simultaneous) read of different "post areas" (by your team members) will better enable your selection process.

    Usually - but not always - my small tech group starts "simply" - enabling improved understanding - and (only then) is in a position to make a more considered purchase decision...   By my read - you/your group appear to have "punted" that responsibility! (to those here)   You state that you must, "Know for sure" - should not your group become more active/involved in the acquisition of such knowledge?   (and - can one ever, "Know for sure?")

  • 0 in reply to cb1_mobile
    Intellectual 490 points
    I think I see the difficulty in answering my question! Let's forget precision because I'm pretty sure I misused the word. The challenge we will be trying to overcome is smooth velocity control at very low RPM. The FAST software seems to be the way to go in that regards. The kit that I linked earlier only comes with instaSPIN BLDC which won't have great speed control at very low RPM. Since the higher current of this kit is required (we will be driving upwards of 60-70 amps for short periods of time) this kit seems like the best choice except for the lack of FAST software. Do you know if one can buy a driver board like this one and use a different control card such as a TMDSCNCD28069MISO. That card contains all the software we need (MOTION and FOC). Seems like the interface makes it portable but it would be nice to know if that card will work on the 82.5A driver board.
    I understand your last point cb1_mobile, but money is something we don't have lots of (school project) so to buy a smaller eval kit to test and play around with then buying a bigger more expensive board once we are sure of what we need leaves us tight in other areas of the project.

    Cheers,
    Jim
  • 0 in reply to Jimbo5760
    Guru 47900 points

    As my small firm/myself are "outsiders" (like you) I'm not properly qualified to search & evaluate all of the boards here for you. (and - again - that's your job - is it not?)

    Now I do believe that 60-70 Amps (even for short periods) is beyond the capability of most (perhaps all) standard boards here. But you must accept that responsibility - I cannot.

    I can tell you that our firm has designed a BLDC Controller able to run reliably @ speeds < 50 RPM - and that this was immensely aided by the use of "Hall Sensors" embedded w/in our BLDC motors. In out case - any/all "motor twitching" is disallowed @ start-up. Later - once the motor's reached stable, target speed - we switch to BEMF commutation.

    I believe that Hall sensored BLDC commutation is your best, fastest & easiest means to achieve the low speed operation you seek. (although - again - no target RPM (beyond low) has been presented w/in your writing.

    Our motors (for now) draw similar currents - run from batteries (18V) and you really must "clamp down" those motors and observe all proper safety precautions!  

    At those high currents electrical noise reduction, signal routing & board traces (WIDE) & layout is uber critical.   Current measurement may prove a challenge as well - suggest you visit Allegro's site.   (ACS758 may be one alternative)

    I don't believe this project will prove, "Quick nor Easy" and I'd suggest a far less current demanding motor for your initial design...

    It appears that you've chosen a motor beyond the capabilities of most power stages here - is such really wise - and well considered?   

    While you "reject" for budgetary reasons - KISS dictates small, simple - and most always yields the best, easiest & fastest solution.   "Aiming for the moon" - on your "first go" - Not so much!

  • 0 in reply to cb1
    Intellectual 490 points
    "As my small firm/myself are "outsiders" (like you) I'm not properly qualified to search & evaluate all of the boards here for you. (and - again - that's your job - is it not?)" -Ideally a sales rep or tech support for the company you're querying should be able to give a definitive answer. That's what I'm hoping for. Since the literature doesn't mention it, I'm not buying a bunch of different products to determine which one is right. Money doesn't grow on a student's trees. At least not my trees!

    "I don't believe this project will prove, "Quick nor Easy" and I'd suggest a far less current demanding motor for your initial design..."
    -This is probably going to be the route that we will have to take. It's only a prototype and will likely meet our needs!

    Thanks for all of your help cb1! I'm still hoping a TI rep could chime in on whether or not we could interchange various control cards among their development kits, ie using an F28069M instead of the F28035 in the DRV8301-HC-C2-KIT.
  • 0 in reply to Jimbo5760
    Guru 47900 points

    Being a weekend - only the "hardest" of hard-core were likely to respond.   (thus my effort in your behalf)

    Many here were (and are) in your "financial shoes" and that's why I urged KISS - which enables a reduced cost purchase of a motor-driver - available here - and commutated via hall-sensors for your "low speed" requirements.   Choosing a, "too demanding" initial task is quite common - the 60-70 Amps you listed proves a challenge even for those w/much experience - and (somewhat) deeper pockets...

    Bon chance mon ami...   Do consider KISS - it has saved our/others rear ends more times than we can count...

  • 0
    TI__Guru** 119680 points
    F28035 can not run InstaSPIN-FOC nor InstaSPIN-MOTION.
    The kit you are looking at is supported through controlSUITE and has InstaSPIN-BLDC and standard sensorless (SMO) based FOC.
    You can use this same inverter and just add TMDSCNCD28069MISO or you can purchase instead DRV8301-69M-KIT which includes the 69MISO card. This allows you to do InstaSPIN-FOC (sensorless torque or velocity) and InstaSPIN-MOTION (sensorless velocity or sensored/encoder velocity or position).
  • 0 in reply to ChrisClearman
    TI__Guru** 119680 points
    if this is for a traction like application - like an electric powered skateboard - you will have some challenges, especially with sensorless control, in regards to start-up. additionally, if you are trying to synchronize two drive wheels it becomes REALLY tough. I feel confident in saying that as a student you should look in another direction. And on top of that I'm sure you are trying to use cheap, low inductance, hobby style motors which have their own set of control challenges. AND you are working in very high amperage, which combined with the low inductance makes current measurement - and hence control - quite challenging.
  • 0 in reply to ChrisClearman
    Intellectual 490 points

    Thank you Chris!