Problems with PID parameter tuning on DCS.
Thread Content
There is a heating furnace on site to heat the natural gas, and the flow rate of natural gas remains very stable. The set temperature for the furnace core is 260 degrees; when the core temperature reaches 300 degrees, the temperature protection mechanism activates and the heating furnace stops working. Currently, when the core temperature reaches 260 degrees, the heating furnace does not stop and continues to heat until it reaches 300 degrees, after which the high-temperature protection mechanism triggers and the furnace shuts down. How should the PID parameters be set so that heating stops when the core temperature reaches 260 degrees? (The previous settings were a proportional value of 10, an integral value of 80, and a derivative value of 70 – these settings worked fine before, but last night the core temperature could no longer be controlled.) Please help, sir
This has little direct relation to the PID parameters; the cause is likely due to the valve or thermometer losing control. Check the instruments and valves – the PID parameters can’t handle such issues. Moreover, no matter how excellent the PID parameters are, they cannot stop the heating process; they can only control the temperature of the heating furnace in order to reduce the temperature of natural gas. I don’t know what kind of control scheme you are using; I can only guess.
Based on the observed phenomenon, it seems unrelated to the PID parameters; it is likely a fault with the thermostat or actuator, so it should be checked one by one.