Drilling operation control using multiple concurrent hydraulics models

Abstract

A control system for drilling a subterranean well can include multiple concurrently running hydraulics models, each of the hydraulics models outputting a pressure setpoint, in real time during a drilling operation. A method of controlling a drilling operation can comprise concurrently running multiple hydraulics models during the drilling operation, and switching between outputs of the multiple hydraulics models to control the drilling operation, the switching being performed during the drilling operation. Another method of controlling a drilling operation can include controlling operation of at least one flow control device, thereby maintaining a pressure at a pressure setpoint, and selecting the pressure setpoint from among outputs of multiple concurrently running hydraulics models.

What is claimed is: 
     
         1 . A control system for drilling a subterranean well, the control system comprising:
 multiple hydraulics models, whereby each of the hydraulics models outputs a pressure setpoint, in real time during a drilling operation.   
     
     
         2 . The system of  claim 1 , further comprising a controller and a selector, wherein the controller controls operation of at least one device, and wherein the selector selects which of the multiple pressure setpoints is input to the controller. 
     
     
         3 . The system of  claim 2 , wherein the device comprises a flow control device. 
     
     
         4 . The system of  claim 3 , wherein the flow control device comprises a choke which variably restricts flow from a wellbore. 
     
     
         5 . The system of  claim 3 , wherein the flow control device controls flow through a standpipe. 
     
     
         6 . The system of  claim 3 , wherein the flow control device controls flow between a standpipe and a mud return line. 
     
     
         7 . The system of  claim 1 , wherein the multiple hydraulics models comprise multiple instances of a same hydraulics model. 
     
     
         8 . The system of  claim 1 , wherein the multiple hydraulics models run concurrently. 
     
     
         9 . A method of controlling a drilling operation, the method comprising:
 running multiple hydraulics models during the drilling operation; and   switching between outputs of the multiple hydraulics models to control the drilling operation, the switching being performed during the drilling operation.   
     
     
         10 . The method of  claim 9 , further comprising controlling operation of at least one device, thereby maintaining a pressure at a pressure setpoint output by one of the multiple concurrently running hydraulics models. 
     
     
         11 . The method of  claim 10 , wherein the device comprises a flow control device. 
     
     
         12 . The method of  claim 11 , wherein the flow control device comprises a choke which variably restricts flow from a wellbore. 
     
     
         13 . The method of  claim 11 , wherein the flow control device controls flow through a standpipe. 
     
     
         14 . The method of  claim 11 , wherein the flow control device controls flow between a standpipe and a mud return line. 
     
     
         15 . The method of  claim 9 , wherein the switching further comprises switching from a first hydraulics model output to a second hydraulics model output. 
     
     
         16 . The method of  claim 9 , wherein the switching is performed in response to a change in an objective of the drilling operation. 
     
     
         17 . The method of  claim 9 , wherein the switching is performed in response to detection of an event. 
     
     
         18 . The method of  claim 9 , wherein the switching is performed in response to a comparison between a measured drilling parameter value and the drilling parameter value as predicted by the hydraulics models. 
     
     
         19 . The method of  claim 9 , wherein the switching is performed manually. 
     
     
         20 . The method of  claim 9 , wherein the switching is performed automatically. 
     
     
         21 . The method of  claim 9 , wherein running the multiple hydraulics models further comprises running the hydraulics models concurrently. 
     
     
         22 . A method of controlling a drilling operation, the method comprising:
 controlling operation of at least one device, thereby maintaining a pressure at a pressure setpoint; and   selecting the pressure setpoint from among outputs of multiple hydraulics models.   
     
     
         23 . The method of  claim 22 , wherein the selecting further comprises switching from a first hydraulics model output to a second hydraulics model output. 
     
     
         24 . The method of  claim 23 , wherein the switching is performed in response to a change in an objective of the drilling operation. 
     
     
         25 . The method of  claim 23 , wherein the switching is performed in response to detection of an event. 
     
     
         26 . The method of  claim 23 , wherein the switching is performed in response to a comparison between a measured drilling parameter value and the drilling parameter value as predicted by the first and second hydraulics models. 
     
     
         27 . The method of  claim 22 , wherein the selecting is performed manually. 
     
     
         28 . The method of  claim 22 , wherein the selecting is performed automatically. 
     
     
         29 . The method of  claim 22 , wherein the hydraulics models are concurrently running. 
     
     
         30 . The method of  claim 22 , wherein the device comprises a flow control device.