US 11,693,436 B2
Control systems for valve actuators, valve actuators and related systems and methods
Mark D. Ollander, Forest, VA (US); Daniel E. Carlson, Rustburg, VA (US); and Michael Adam Rumore, Lynchburg, VA (US)
Assigned to FLOWSERVE PTE. LTD., Singapore (SG)
Filed by Flowserve Management Company, Irving, TX (US)
Filed on Sep. 25, 2020, as Appl. No. 17/33,038.
Application 17/033,038 is a continuation of application No. 16/388,656, filed on Apr. 18, 2019, granted, now 10,976,757.
Prior Publication US 2021/0011502 A1, Jan. 14, 2021
Int. Cl. G05D 17/02 (2006.01); G05D 7/06 (2006.01); F16K 31/60 (2006.01)
CPC G05D 17/02 (2013.01) [G05D 7/0635 (2013.01); F16K 31/60 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A valve system comprising:
a valve actuator for controlling a position of a valve element in a valve in order to control flow through at least a portion of the valve; and
a control system for controlling the valve actuator, the control system configured to:
instruct the valve actuator to move the valve element toward an unobstructed first position in the valve to enable fluid flow through the at least a portion of the valve;
instruct the valve actuator to move the valve element from the unobstructed first position to a second closed position in the valve to reduce the fluid flow through the at least a portion of the valve, wherein the valve element is at least partially seated to reduce the fluid flow in the valve in the second closed position;
monitor at least one characteristic of the valve system during movement of the valve element to the second closed position comprising a hard stop;
determine a drift of a sensed location of the second closed position based on the monitored at least one characteristic of the valve system by calculating a difference between a previously recorded closed position and the second closed position; and
during each movement of the valve element, maintain a predetermined location of the unobstructed first position while actively adjusting the location of the second closed position comprising the hard stop each time the drift in the sensed location of the second closed position is detected.