Falcon 500, Syncronous or Induction

Our mentors keep bugging me to find out if the three phase motors we got this year can be speed controlled like our tooling, but I can find no software reference for it, so I’m asking here.
How do motors like the Three-phase FRC motors (neos and Falcons) react under load? I’m looking for speed-lock or induction style speed control, where we can just, sit at some frequency on the controller, and lock the speed that way. As opposed to a Synchronous motor, like you might find in the hobby environment, where the phase is controlled by the position of the motor (somewhat like a DC brushed motor).

I would really like to be able to set perhaps the speed of a shooter or drive base with the frequency of the controller alone if this is something that we have the ability to do in software.

Thanks so much for reading.

The FRC BLDC motors are commutated based on the position of the rotor, like hobby BLDCs. There’s no other way to commutate them with the legal controllers/software.

Check out https://motors.vex.com/ for motor curves, and Vex has a really great explanation of how BLDCs are commutated here: https://motors.vex.com/brushed-brushless

If you want to control your motors to have a specific speed, you can open-loop them to a duty cycle which will get you approximately the right speed but changes under load, or you can use speed control (PID loop) to make them drive at a certain speed and react to changes in load.

I think I answered your question, but let me know if you’re still curious.

These are sensored brushless DC motors. They do not work like AC motors

Normally, Sensorless Brushless DC motors do not have a good amount of low-end torque, but the sensor in the Falcon (and NEO) make up for that.

The sensor lets the controller know where the rotor is at and which windings to send power to

You did exactly thank you!
It’s unfortunate that we can’t commutate them like AC motors, but alas.

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