Valve control device, process engineering plant having a valve control device, diagnostic method and use of a valve control device

Abstract

A position closed-loop controller for a valve control device of a process engineering plant may include a pneumatic control output for a pneumatic control variable, a first signal input for a pilot signal, such as a process control signal from a process closed-loop controller of the process engineering plant, and a second signal input for a position actual signal with regard to a control valve. The position control-loop controller may be designed to generate the pneumatic control variable for an actuator to actuate the control valve based on the pilot signal and the position actual signal. The position closed-loop controller may calculate an approximation signal using a configurable closed-loop controller model based on a closed-loop controller proceeding from the pilot signal. The closed-loop controller model may be configured such that a signal generated by the particular closed-loop controller proceeding from the approximation signal corresponds to the pilot signal.