Method and system for controlling a process fluid stream and positioner

摘要

In a method or system for controlling a process fluid stream within an industrial process plant, a pump is provided in series with a control valve having an associated positioner to control the fluid stream. A required fluid passage quantity for the process fluid stream is set by positioning the control valve with the positioner into a respective valve position and capturing an actual position of the valve. A physically sensible actual property value related to passage of the process fluid through the control valve is determined. The actual property value as well as the actual valve position are evaluated by an evaluation routine with respect to a predetermined optimization parameter specific to the valve with its associated positioner. If a deviation occurs from the optimization parameter, a pump drive value for the pump and control valve position drive value for the valve positioner are tuned to each other in such a way that the optimization parameter is approached.

主权项

1. A method for controlling a process fluid stream within an industrial process plant, comprising the steps of:
providing a pump in series with a control valve having an associated positioner to control said fluid stream; setting a required fluid passage quantity for said process fluid stream by positioning said control valve with said positioner into a respective valve position and capturing an actual position of said valve; determining a physically sensible actual property value related to passage of the process fluid through the control valve; evaluating the actual property value as well as the actual valve position by an evaluation routine with respect to a predetermined optimization parameter specific to the valve with the associated positioner; and if a deviation occurs from the optimization parameter, tuning a pump drive value for said pump and a control valve position drive value for said valve positioner to each other in such a way that the optimization parameter is approached without substantially altering a fluid passage quantity through the valve controlled according to said required fluid passage quantity by slowing a speed of the pump combined with opening the control valve further or increasing a speed of the pump combined with closing the control valve further.