I made the following sheet to think about the limitations of FOC driving, and help size various components…
Perhaps it is helpful?
Basically, I would say the limitations are not so much the sensing, as a 14 bit sensor like the AS5048 will still have >10 distinct positions on a (theoretical) 200 pole-pair motor…
I think the limitations are around the FOC algorithm iteration rate, compared with how smoothly / quickly you want to drive the motor…
The sheet makes this obvious, unless I have made some mistake in my thinking or calculations. If you do take a look, and spot an error or have any feedback do let me know.
I still plan to add current sensing and FET timings to it when I have time…