PlumberBob
Member
I am looking for recommendations for a small controller to implement a feed-forward or IMC model control strategy.
I have a pretty straight-forward temperature controller for a very sluggish batch reactor. Like most things thermal, it is slow to heat up (20-60C in about 90 min), but even slower to cool off (< 1C/hr).
The existing solution is a simple PI controller with a wide PB that will reach temperature in about 90 min. However, the customer has low tolerance for overshoot (delays transfers) and is impatient. We know that the system can reach (and fly-by) the set point in about 40 minutes at full-power. We also seen that you can run full power for 25 minutes, shut it off and let it coast up pretty close to the setpoint in under an hour (requires a good guess for each load recipe).
I would like to implement an algorithm that tracks the integrated heater input and predicts where it will end up. I think I can get away with two AI, one AO, a set-point adjustment, two DI or buttons for man/auto and reset, and a 2 line display for SP, PV, and future process value. I have the math in hand, but can't find HW that is more flexible than PID, but less involved than a full PLC or working up from a bare microcontroller (i.e., PIC, Arduino, etc.)
Any recommendations?
Thanks,
Bob
I have a pretty straight-forward temperature controller for a very sluggish batch reactor. Like most things thermal, it is slow to heat up (20-60C in about 90 min), but even slower to cool off (< 1C/hr).
The existing solution is a simple PI controller with a wide PB that will reach temperature in about 90 min. However, the customer has low tolerance for overshoot (delays transfers) and is impatient. We know that the system can reach (and fly-by) the set point in about 40 minutes at full-power. We also seen that you can run full power for 25 minutes, shut it off and let it coast up pretty close to the setpoint in under an hour (requires a good guess for each load recipe).
I would like to implement an algorithm that tracks the integrated heater input and predicts where it will end up. I think I can get away with two AI, one AO, a set-point adjustment, two DI or buttons for man/auto and reset, and a 2 line display for SP, PV, and future process value. I have the math in hand, but can't find HW that is more flexible than PID, but less involved than a full PLC or working up from a bare microcontroller (i.e., PIC, Arduino, etc.)
Any recommendations?
Thanks,
Bob