Conveyor speed feedback

Hello everyone.
I have a feedback from encoder to measure the speed of conveyor, if in need to control the speed of the conveyor to a preset speed in mm/s .the conveyor is driven by VFD and the reference speed is analog value from s7-1200 plc
The question is how to make the drive follow the preset speed and minimize the error .

Hossamhegab said:

Hello everyone.
I have a feedback from encoder to measure the speed of conveyor, if in need to control the speed of the conveyor to a preset speed in mm/s .the conveyor is driven by VFD and the reference speed is analog value from s7-1200 plc
The question is how to make the drive follow the preset speed and minimize the error .

Click to expand...

Attach the encoder to the VFD, and configure the VFD to regulate its own speed.

There's no encoder card on the VFD.itis already existed system

PID controller is the best way to control the speed of conveyor to follow the set point
call a PID function block
then make actual value MD taking from encoder pulses (PV-PER)
you have the set point(SP-INT)
and also the function have (selection of P,I,D values)
tune the PID parameters by choosing the optimal value for your application
you can create rate limiter or filtering values to pass the manipulated value (LMN) to reduce transients
note set point is PIW
manipulated value is PQW which sent to drive motor
there is a drive (vector control with feedback like lenze 9300 servo inverter or uni-drive sp can perform your job accurately without PLC but the cost is high)

PID is a good solution for my application. The system now working correctly
Thanks eng mostafa and I will be pleased to be in touch with you