Does an AC Servo motor have a similar mode of operation to a BLDC motor? Can Odrive be used to drive an Industrial AC Servo Motor? I would think so, but I am not personally familiar with what an “AC Servo Motor” is defined as so i don’t know so. Moreover, I can’t find any examples of people using Odrive with Industrial servo motors - except for the above example.
Well, technically yes but in practice you’d need a new and isolated power stage that can handle ac current and higher voltages and new firmware to run it. And industrial servo motors do come as brushless dc motors as well as ac motors, they’re just a lot more expensive.
What you know as a “Brushless DC Motor” is actually the same thing as a “Permanent Magnet Synchronous AC motor” aka PMSM. Normally a PMSM is wound for servo control ie has sinusoidal back-EMF. Sinusoidal EMF motors work better with the FOC control scheme that the ODrive uses, which is the same as industrial servo drives. So from that point of view, they are more ideal than “hobby” style brushless motors.
However, industrial servomotors are normally designed to work at mains voltages (think really-low KV), i.e. in industrial drives the DC bus is supplied by a bridge rectifier directly from the mains. On 230V single phase this would produce 350V DC. On 415V 3-phase, more like 600V DC.
You can use industrial motors designed for 600V on the 56V ODrive, but you need to beware that you will not get a good current-control bandwidth due to the high inductance and high resistance of the motor, and you will not get anywhere near the designed max RPM of the motor, due to the low kV. You also might not be able to produce full torque, if the resistance is really high.
Btw, please don’t attach a mole wrench to a motor shaft. It’s not a good idea.