• State
  • Locked Locked
  • Replies 1 reply
  • Subscribers 30 subscribers
  • Views 367 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

max DC Bus Power for DK-LM4F211-DRV8312

Tao He1
Intellectual 320 points

Other Parts Discussed in Thread: DRV8312

hello,  I recently received my DK-LM4F211-DRV8312 Motor Control Development Kit and am very enthusiastic about the possibilities! Now I have a BLDC motor with 36 input votage and I want to power this motor via DK-LM4F-DRV8312. My problem is that the standard input DC bus power for DK-LM4F-DRV8312 is 24 v, but my motor needs 36 v power supply. I have checked that it is possible to supply up to 52.5 v voltage to DRV8312, so does that mean I can give a DC bus power for DK-LM4F-DRV8312 up to 52.5v? If not, how to easily customerlize the DC bus power for DK-LM4F-DRV8312?

I appreicate any answer and direction!

  • 0
    Guru 117855 points

    Quick answer we fear - not much to your liking!  You must carefully survey any/all components which may come into contact w/both your raised motor supply voltage - and any additional voltages (such as BEMF) which are sure to increase due to the rise of your motor supply voltage.

    Board FETs, filter caps, perhaps even gate driver ICs - all require great scrutiny.  (and there are likely to be many more)

    To further confound/complicate - should your motor be under load - and then abruptly halted/slowed either deliberately (via speed command), some fault, or other means - voltages much exceeding the raised motor supply voltage - are likely to be encountered!  (this due to the motor's ability to quickly switch from power user to power generator!)    

    This likely explains kit vendor's choice of a 24V motor - so that a reasonable "safety margin" is created and hopefully maintained.

    And - should these voltages exceed the specs of "contacting" board components - results may not be greatly in your favor!   (understatement - I strongly advise against your employing voltage beyond that recommended by any vendor!)

    Can it be done - perhaps.   Does it make sense (i.e. will the design prove robust) - suspect that's a decision which you alone must make...

    Best course for you - I believe - find a motor which has electrical ratings (especially voltage) much better matched to your target driver board... 

    In support of Motor Control kit vendor - they had "price & size points" to meet - it is assumed that accommodating your elevated voltage application fell outside their target...

    While I am in no way suggesting nor recommending such course - you may be able to exploit this kit's software & logic facility - by intercepting and bringing out the appropriate, low level drive signals - for attachment to a properly designed/constructed "power board."  Again - you alone must insure that no voltage beyond that specified by your Motor Control kit vendor is - at any time (however briefly) (credit UCLA law) - introduced to your original kit board. 

    One more note of caution (there are many more - you must find/comply) - early in our group's motor control development we sometimes failed to fully/properly "lock down" our MUT.  (motor under test)  We no longer repeat that failing!  That motor, connected power-supply, and interconnects - all "launched" - the "imperfections" (i.e. ragged hole) in our lab's "dry-wall" - bear witness to the destructive capability of kinetic energy - when improperly managed and/or safe-guarded... 

    (no persons, motors, power-supplies, interconnects nor lab dry wall were harmed during the creation of this forum response...)