Hi All,
I have developed sinusoidal commutation for a PMSM motor. I am using hall sensors to estimate angle in between two hall states and generating sine PWM using Sine Lut table. Everything is working smoothly.
But i stuck into regeneration braking feature, for trapezoidal commutation you change the PWM switching pattern and current direction changes to opposite. But i am not getting any article or any information for sinusoidal commutation. here all three phases are busy all the time.
I tried one solution to give negative torque command for regeneration and it is working. i can see the current in negative direction but it is not as smooth as trapezoidal one. it is giving jolt to the motor and huge phase current observed for a few seconds which can damage the system. i observed that motor stopped suddenly and try to run in opposite direction because of the negative torque command. later i kept minimal negative torque command and observed same behavior.
Am i doing anything wrong by giving negative torque command? is there any special switching pattern for regeneration like trapezoidal one?
please give some clue or idea.
thanks
Amit.
