Hello
I'm planning to building a segway clone using two 24V 400W BLDC motors. I have kind of figured out the rest of the electronics but I'm not yet sure about the motor driver for the motors. I looked up online and found that an ESC and arduino can together be used to contol BLDC motors. I also tried this instructable
But I still can't figure out how. I don't know if it applies to the motors I'm using.
Could someone please guide me in detail on how to do this.
You need a 3-phase MOSET bridge capable of high current(*), and a good fast current sensor.
Then a 3-phase motor driver chip to drive the MOSFETs and shutdown on gross-overcurrent (probably
a comparator or two to generate this error signal).
Then a microcontroller with a PID loop to generate the direction and PWM signals to feed to
the driver chip (an Arduino one presumes here).
Found this link which might be a starting point. http://www.atmel.com/images/atmel-2596-sensor-based-control-of-three-phase-brushless-dc-motors_application-note_avr443.pdf
(*) high power high current MOSFET bridges are tricky to get right - shoot-through or over current or
over-voltage spikes can mean instant destruction so protection components are important and you
must use decent fast low-impedance gate drivers.
Thanks a lot. I ll try working on it. If it turns out to be too complicated , i'll just switch to brushed motors. 
Did you have any success? I'm looking at doing the same.....
Hi,
i am also interessted in setting up a BLDC shield and researching this at the moment. It seems to be a very wide field.
You picked yourself a quite difficult application which containes the following core challenges.
Lets start from the motor side. A BLDC Motor needs some kind of 3 phase pulsed, direction inverted DC current. This comes close to 3 phase AC. The major difference to 3 ph. AC is that BLDC Motors do not need sine wave current, they just need to have the current commutated in the right moment, trapezoidal is sufficient and gives higher torque anyway.
To do the commutation you need to know the position of the rotor, although there is sensorless commutation possible with BLDC through FOC (field oriented commutation), i urgently recommend sensored methode for your application, due too you will need low speed and close to position control. I think even the 3-Hallsensor will not be sufficient on its own and an angle sensor becomes neccessary (just in my opinion).
As told above by markT the power stage driver, commonly called MOSFET with their pre drivers is a science of its own. one of the simplest way is to use MOSFETs to set up three H-bridges, use a pre driver and feed this system with your 6 PWMs from the ?C. I searched alot and came down to the DRV8301 from Texas Instruments from which i already got a free sample. It has alot of the requirements onboard such as protection of shoot through..... it also provides an SPI interface for over current, over/under voltage, over temperatur....
The chip also provides programmable current feed back from the MOSFETs and a supply voltage for the ?C through buck converter. It has a charge pump for boot strapping methode (avoids the need for P-Channel MOSFET for the H-Bridge high side) this feature i personaly dislike, but it is hard to find pre drivers for complementary MOSFET.
There is a evaluation kit from TI available at the moment, offering the ?C and the drive stage for 66USD, unfortunately it only provides 14 amps peek current and is designated for FOC. Therefore the drive stage would have to be adapted for higher current (using stronger MOSFETs and adapting the current feedback) and hall sensors or angle feedback would have to be implemented. I have ordered this one too, just to get more ideas how this BLDC thing is working. There are several different of these chips available from all well known manufacturer which work almost similar.
I intend to use the power stage drive from the evaluation kit and wire it to an arduino due because the ?C which comes with the evaluation kit has to be programmed in C which i dislike too.
Another sipmle methode for the drive stage would be the half bridges from infineon. The BTN8982 provides an absolut peak current from 117 amps, which could become sufficient for your application. Also they have integrated shoot through protection and current and failure feedback, just in a much simpler way.
in my actuall experimental arrangement, i am trying to figure out if this is all possible with an arduino uno. Allways considering the very low speed which is needed for my project (less than 2 rpm`s/second).
Would be great to share our experiences. By the way, i am using an angle positon encoder which i got provided for free from AMS (AS5048A) which is a bloody lovely thing, in my opinion.
cheers
One thought was to use the BLDC gimbal controller by Martinez (V3) but in reverse (sort of....)
(see http://witespyquad.gostorego.com/brushless-gimbal-v3-0-controller-module-w-sensor-martinez.html)
as used/shown in the great little Mini Segway that IgorZgCro has built recently. Check out this.....
I’m just waiting on the bits to test the Mini Segway project myself with the idea that MAYBE a high current output driver stage could be added to handle say 800 Watt Brushless motors. A long shot but will be good fun as a diversion if nothing else….
My first two versions gave me a Segway that did work but the backlash in the wheelchair motors did become a problem in the long run.... Hence the BLDC concept seems a much better solution - but yes many more degrees of complexity. See http://www.brucewhite.net/Segway%20Project/Index.htm for the first two versions of my project.
Cheers
Bruce