3 phase motor drive for low voltage high current (not a hobby esc)

[qwaarjet]

I'm looking for a 3 phase drive that can operate in open loop or use feedback like back EMF or encoder or both preferably. This need to drive bldc motor from a quadcopter for a bench experiment for a school lab so low voltage but fairly high current. I don't want just a regular ESC because I cant control the feedback parameters but most VFDs require a encoder and cant be run open loop. Building a custom solution is an option but I would rather not it there is commercial product that could be used. Anybody got an idea?

[Seekonk]

Hobbyking has plenty cheap.

[qwaarjet]

I can't control the feedback on a regular hobby drive almost all of them use back emf  for feedback. I want one that can run true open loop

[eneuro]

This interesting sensorless BLDC driving TI technology InstaSPIN™-BLDC, however not sure if HobbyKing has already something which implements this.


There is quite nice introduction - maybe something more than kits are commercially available? 


Definitelly will put my hands on this technology after a few other projects are finished, while need drive a few BLDCs in another projects and it could be nice use cheaper BLDC motors without Hall sensors

[mazurov]

I can't control the feedback on a regular hobby drive almost all of them use back emf  for feedback. I want one that can run true open loop

If you attempt to run BLDC open loop you'll get a stepper with very large step. Any hobby ESC runs open loop at startup with characteristic jerking motion of the rotor. You can rotate a BLDC like that with 3 switches by energizing 2 windings at a time in a certain sequence. I made a controller once using Allegro A4960 ( http://www.circuitsathome.com/diy-2/advanced-brushless-dc-motor-controller ); if you screw up the settings of the chip you will get open loop.