I designed Permanent Magnet Brushed DC Motor Controller hardware (H-Bridge) for Elevator Door Control. I used dsPIC33EP as main controller. Centre door opening and closing application. So there is a door on each side. In this application, spring is connecting between the two doors. One end of spring is connected to right side door right end and another end of spring is connected to left side door left end. As door opens, the spring will pull. For that I require more power (torque to open the door) and it is done fine.
I have simple PWM Control for speed; i have PI Controller for controlling Speed. My PWM Frequency is 20 KHz. I have 24V Brushed PMDC Motor.
Now the problem is braking and door closing (Reverse direction). When i give brake command (Short Armature winding) it will slip and back to door close because of spring is pulled. And door is close very fast when I give door close command. From above i cannot able to control speed while door close. How can i control the speed while door close with spring connected?
Is Permanent Magnet Brushed DC Motor is ok for this type of application?
If not then which motor will work for this type of applications? As BLDC will work?
So please give some solution for above case.
Thanks and Regards,