04404637 is referenced by 7 patents and cites 10 patents.

A variable limit is utilized to prevent a position controller which requires a velocity set point signal from overdriving a stuck control valve. Control based on a comparison of the actual position to desired position is utilized unless the valve is stuck. If the valve is stuck, the variable limit controls the velocity set point provided to the position controller until such time as the valve becomes unstuck.

Title
Process control system
Application Number
6/258969
Publication Number
4404637
Application Date
April 30, 1981
Publication Date
September 13, 1983
Inventor
William B Bard
Bartlesville
OK, US
John O Walters
Bartlesville
OK, US
Assignee
Phillips Petroleum Company
OK, US
IPC
F01D 17/02
G05B 15/00
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