john61ct said:
Isn't Nucular a true FOC controller? aka flux-vector control
Correct me if I'm wrong but my understanding is that means not just manipulating gross current levels to influence torque, as with the CA, maybe similar to "sinusoidal commutation" controllers?
But much more precise control based on monitoring of current sensors internal to the motor,
and powerful CPUs to process the signal data, predicting the rotor angles real-time.
If this is a reasonable description, then all such FOC controllers perform this functionality better than the CAv3 can?
But the issue here is that control based on **power**, watts as opposed to amps, simply is not useful?
Just trying to grok the fundamentals here, appreciate the feedback.
Field weakening isn't magical.
It costs you more current to use it.
You lose motor efficiency to use FW.
I can't say for your motor and how effective FW will be for you.
The ideal motor for FW is an IPM inrunner.
You need exposed iron in the armature for it to work.
The magnets are literally in the way of using FW effectively.
This is why IPM motors are the best option for FW since the magnets are inside the iron.
My best suggestion to you is try FW on your motor under load.
I have attempted to use it on several outrunners and the RPM gains were so small as to NOT matter.
I tried it on a couple of inrunenrs and they were a bit better, but still not worth using FW for greater current usage.
I have never tried it on a hub motor, but they too lack lots of exposed iron so I don't expect much.
FOC is definitely the best motor control around since it is the most precise and controls motors the best.
However FW has nothing to do with FOC. Trapezoidal and sinusoidal controllers can also implement FW.
I'm not sure how a CA can possibly implement real FW or phase current control. The CA would need direct access to the halls and phases to do this. I just looked at the latest CA manual and it operates as I expected. There is no conceivable way it can implement field weakening or phase current control. It just doesn't have that ability. A CA can create throttle curves. Even with a 3 speed switch, it is only controlling throttle voltage. It has no way to control phase amps or FW or hall delay/advance. A CA uses a shunt in series with the battery and controller or the shunts inside the controller for detecting battery amps. This is NOT the same as phase amps or controlling phase amps.
Watts = volts X amps
Battery watts = battery voltage X battery amps
Motor watts = battery voltage x phase amps
If you look at a lot of better controllers, they have a shunt or current sensor on each phase connection. They are used to directly measure phase amps for each phase and that gives the MCU direct feedback on what the phases are seeing for current. The Nucular controllers use shunts on the battery side and some math to calculate phase amps. It's just one of several methods to get phase amps.