Siemens SIMATIC S7-1200 Function Manual page 35

Equation for PID controller
The following applies for the step response of the PID controller in the time range:
t = time interval since the step of the control deviation
Response of a controlled system with different controller structures
Most of the controller systems occurring in process engineering can be controlled by means
of a controller with PI-action response. In the case of slow controlled system with a large
dead time, for example temperature control systems, the control result can be improved by
means of a controller with PID action.
①
②
③
w
x
Controllers with PI and PID action have the advantage that the process value does not have
any deviation from the setpoint value after settling. The process value oscillates over the
setpoint during approach.
PID control
Function Manual, 03/2017, A5E35300227-AC
2.6 Control Response at Different Feedback Structures
No controller
PID controller
PD-action controller
Setpoint
Process value
Principles for control
35