Hi,
We have designed the HUB motor ( PMSM ) controller . It is supposed control the ebike. We have used Space vectror modulation
technique to control the motor. The position management based on digital hall sensor. The motor has 48 poles and has an operating voltage of 48V.
PWM switching frequency is 16KHz.
We are actually stuck with one problem. Initially when you start the motor up to 40rpm, we get some noise and vibration and then later it becomes
pretty smooth. The problem iam explaining is only on loaded condition. In free spin, it is smooth all over. The noise that we get is some thing similar
to flight flying in stable condition. Initially for two mechanical rotation we modulate the PWM on every 60deg electrical angle after that when we start getting the rotar angle position, we modulate PWM for every 62.4us.
The problem is not with the motor because it runs smoothly with China controller.
Please let me know, if any-one has experience of facing such problem and resolving it