Hi Daniel, I am developing BLDC (Hall) driver with S32K144, may I have a reference for brake function? should I disconnect the bus line when braking? many thanks.
Hi Rick,
It all depends on how your power stage is designed. Typically, there are 2 major use-cases:
In this case, you typically have a diode protection circuit that ensure you can't push back the voltage/energy into the battery/grid, hence you do not have to take any additional precautions to protect the power source. Nonetheless, you need to dissipate somehow the energy, hence you have a break transistor to modulate the rate of discharge.
Typically, you need to implement a simple PI controller that computes the difference/error between the reference DC Voltage Link allowed from the power source the actual DC Voltage recovered from the motor. Then based on the error value you open the braking transistor more or less.
In conclusion: if you do not have the diode protection for the power supply, and you need to use the resistive breaking, then you need a method to disconnect the power supply - perhaps using a simple IO relay switch.
Hope this helps!
Daniel
Hi Daniel, thanks for your professional support.