I have questions regarding PID control
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This post was last edited by dzsunshubin on 2017-4-17 21:36. I am a process operator and don’t quite understand PID. I would like to ask everyone: is the ratio related to the range of movement of the control valve’s position, and is integration related to the duration of time over which the control valve operates? I would appreciate your guidance.
PID are the three operating laws of regulators; P is the proportional law, meaning that the output signal of the regulator is proportional to the input error； I represents the integration law; that is, the output of the regulator equals the integral of the input error. As long as there is an error, the output of the regulator will continue to increase or decrease until the error is eliminated ； D is the differential law, meaning that the output of the regulator is proportional to the rate of change of the input. Differential action occurs only when the input signal changes; the faster the input signal changes, the greater the change in the output signal.
PID control is based on the \"error\"; the P component acts according to the magnitude of this error, with its output being proportional to the size of the difference between input and output； I operates based on whether a deviation exists, outputting a value proportional to the time integral of the deviation; it activates as long as there is a deviation, and its function is to eliminate residual errors ； D operates based on the \"rate of change of the deviation\", outputting a value proportional to the rate of change of the input deviation, thereby providing lead compensation.