I'm having trouble with a gear motor being powered by a power supply, while it is being driven by the load in the same direction as the driver wants to drive it. Here is a simple diagram:
The gear motor is the prime mover in a winch system that lifts and lowers a mass of about 25 pounds.
for reference this is the motor:
This is the motor driver:
And this is the power supply:
I'm controlling the system by doing all speed/position control on a raspberry pi, sending forward/backward duty cycle commands to the roboclaw over serial. When lifting the system performs exactly as expected: the motor smoothly rotates. Initially, when lowering, if I sent the motor driver a duty cycle to lower it would jerk, then freewheel, then lower very slowly, and that channel of the driver would no longer function, and would produce a 'damaged' error code. I solved this by simply sending it a duty cycle of 0 and allowing it to lower slowly. This is turning out to be inconvenient for my project timeline, so I'm trying to solve it. I found this video:
So I'm guessing the H bridge on the driver opening up when lowering, allowed the motor to try to sink current into the power supply, the power supply didn't like that and would get fussy and temporarily shut off, thereby shutting off the motor driver, but then the motor driver would get powered on by the back drive voltage of the motor, freak out, freewheel, get damaged, and shut everything down. This was somewhat confirmed by added a forward bias schottky diode to the positive pole of the power supply, as I can now give the system a lowering duty cycle and it will run without destroying itself. HOWEVER now when it is lowering, the behavior is very jerky, like the driving of the motor is producing a current that want's to run into the power supply, but it has nowhere to go. The shuddering vibration is not great for the mechanical aspects of the system, so I'd like to try and solve this. Is there anything I can add to the circuit to help smooth out this behavior? or anything I can add to give the driven motor current somewhere to go?