Other Parts Discussed in Thread: DRV8320, CSD88539ND, DRV10987EVM, BOOSTXL-DRV8320H, MSP-EXP430F5529LP, DRV10983, DRV10987
We are looking to change to BLDC motors in some of our products (which currently use brushed DC). I'm an engineer but have no previous experience working with BLDC, so am looking for a nudge in the right direction :)
In our application the motor is driving a pump (used in drink dispensing equipment). It's a fairly low load application and we just need to drive the BLDC motor FWD/REV (at top speed), brake if needed, and also run at lower speeds at times. One key requirement a fast start / ramp up time so the product responds quickly when activated.
I'm hoping to use sensorless control, and we already have the motor we are trying to drive - it's basic specs are below:
- Phases = 3
- Poles = 8 (4 x pole pairs)
- Rated voltage = 24VDC
- Resistance (phase to phase) = 0.2 Ohm
- Inductance = 0.45 mH
- Rated Current = 5.5A
- Rated Speed = 6500RPM
Note: the rated current if 5.5A (max is approx. 8A), but in our application the motor is only pulling 2.5-3.0A and speed is approx. 7500RPM.
I have been looking at the DRV8312 - does this seem like a good starting point?
If so, is there a way to calculate what ramp up time would be achievable from 0 to 7500RPM - or is it best to get the dev board and jump in? and also what method does the DRV8312 use for initial position detection?)
Again - I'm new to all this so please be gentle :)