When setting the control valve to automatic mode, what knowledge is needed? Could someone give some guidance?

A PID controller (proportional-integral-differential controller) consists of a proportional unit P, an integral unit I, and a differential unit D. Through the setting of three parameters: Kp, Ki, and Kd. PID controllers are mainly suitable for systems with basically linear dynamics and characteristics that do not change over time. 　　 A PID controller is a common component of feedback loops in industrial control applications. This controller compares the data collected with a reference value, and then uses this difference to calculate a new input value; the purpose of this new input value is to enable the system’s parameters to reach or remain at the reference value. Unlike other simple control operations, a PID controller can adjust the input value based on historical data and the frequency of deviations, thereby making the system more accurate and stable. It can be proven mathematically that, while other control methods result in stable errors or repeated fluctuations in the system, a PID feedback loop can maintain system stability.

When setting PID parameters, note that the input unit of the instrumentation system must be set to manual mode

When starting automatic operation, pay attention to whether the valve moves in the reverse direction； The PI parameter should not be too strong. If automatic mode isn’t working, switch back to manual mode and return it to a value close to the experience level (valve opening degree)

Since the control speed is relatively slow in automatic mode, the valve is generally switched to automatic operation only after the system has stabilized; this results in minimal changes in the valve’s opening degree and greater stability of the system. In other words, the switch to automatic mode occurs when the PV value (actual value) is close to the SP value (set value).