# US 11,905,815 B2 · Methods, systems, and computer-readable media for performing automated drilling of a wellbore > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,905,815 B2 - Document ID: US11905815B2 - Status: Granted - Kind: B2 - Application number: 17/957,568 - Filed: 2022-09-30 - Published: 2023-01-26 - Granted: 2024-02-20 - Earliest claimed: 2020-11-13 - Assignees: Pason Systems Corp. - Applicants: Pason Systems Corp. - Inventors: Kshitij Agarwal; Jonathan Alan McIntyre; Choon-Sun James Ng; Aaron Eddy - Web page: https://patentgrep.com/patent/US11905815B2 ## CPC - E21B 44/06: in response to the flow or pressure of the motive fluid of the drive - E21B 21/08: Controlling or monitoring pressure or flow of drilling fluid, e.g. automatic filling of boreholes, automatic control of bottom pressure (valve arrangements therefor E21B21/10) - E21B 47/06: Measuring temperature or pressure - E21B 2200/20: Computer models or simulations, e.g. for reservoirs under production, drill bits - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS ## Abstract There is described a computer-implemented method of controlling a drilling operation. In particular, there is described a computer-implemented method of determining that a differential pressure is in an oscillating state. In response to determining that the differential pressure is in the oscillating state, a weight on bit setpoint is decreased so as to decrease the differential pressure. There is also described a computer-implemented method of determining a difference between a differential pressure and a target differential pressure. The target differential pressure is less than a differential pressure limit. A weight on bit setpoint is adjusted as a function of the difference between the differential pressure and the target differential pressure so as to adjust the differential pressure and thereby reduce the difference between the differential pressure and the target differential pressure. ## Claims ### Claim 1 A computer-implemented method of controlling a drilling operation, comprising: determining a difference between a differential pressure and a target differential pressure, wherein the target differential pressure is less than a differential pressure limit; and adjusting a weight on bit setpoint as a function of the difference between the differential pressure and the target differential pressure so as to adjust the differential pressure and thereby reduce the difference between the differential pressure and the target differential pressure, wherein adjusting the weight on bit setpoint comprises: determining a relationship between a weight on bit and the differential pressure; and adjusting the weight on bit setpoint based on the relationship, wherein determining the relationship comprises: obtaining a dataset comprising weight on bit measurements as a function of differential pressure measurements; and performing statistical analysis on the dataset, and wherein adjusting the weight on bit setpoint based on the relationship comprises: determining a target weight on bit based on the relationship; determining an adjustment to be made to the weight on bit setpoint based on the target weight on bit; and adjusting the weight on bit setpoint based on the determined adjustment. ### Claim 2 (depends on 1) The computer-implemented method of claim 1, wherein performing the statistical analysis comprises performing linear regression. ### Claim 3 (depends on 2) The computer-implemented method of claim 2, further comprising, prior to adjusting the weight on bit setpoint, determining whether a slope of the output of the linear regression is within a preset range of slopes. ### Claim 4 (depends on 1) The computer-implemented method of claim 1, further comprising: determining a lag between the weight on bit measurements and the differential pressure measurements; and adjusting the dataset based on the lag. ### Claim 5 (depends on 1) The computer-implemented method of claim 1, wherein determining the adjustment to be made to the weight on bit setpoint comprises determining (target WOB−current WOB)*dpmax.gain, wherein target WOB is the target weight on bit setpoint, current WOB is the weight on bit setpoint, and dpmax.gain is a constant. ### Claim 6 (depends on 1) The computer-implemented method of claim 1, further comprising, prior to adjusting the weight on bit setpoint, determining whether the differential pressure is greater than a differential pressure setpoint. ### Claim 7 (depends on 1) The computer-implemented method of claim 1, wherein the target differential pressure is based on one or more specifications of a mud motor. ### Claim 8 (depends on 1) The computer-implemented method of claim 1, further comprising, prior to adjusting the weight on bit setpoint, determining whether adjusting the weight on bit setpoint is in compliance with one or more of: a stick slip protocol; a Rotating Control Device (RCD) handling protocol; a limiting protocol; and a stringer handling protocol. ### Claim 9 (depends on 1) The computer-implemented method of claim 1, wherein the target differential pressure comprises a range of differential pressures. ### Claim 10 A computer-implemented method of controlling a drilling operation, comprising: determining a relationship between a weight on bit and a differential pressure; determining, based on the relationship and based on a target differential pressure range, a target weight on bit range, wherein the target differential pressure range is less than a differential pressure limit; adjusting, based on the target weight on bit range, a weight on bit setpoint so as to adjust the differential pressure and thereby maintain the differential pressure within the target differential pressure range; determining that the target weight on bit range is not compliant with one or more existing weight on bit setpoint limits; and in response determining that the target weight on bit range is not compliant with the one or more existing weight on bit setpoint limits, adjusting the target weight on bit range so that the target weight on bit range is compliant with the one or more existing weight on bit setpoint limits. ### Claim 11 (depends on 10) The computer-implemented method of claim 10, wherein determining the relationship comprises: obtaining a dataset comprising weight on bit measurements as a function of differential pressure measurements; and performing statistical analysis on the dataset. ### Claim 12 (depends on 11) The computer-implemented method of claim 11, wherein performing the statistical analysis comprises performing linear regression. ### Claim 13 (depends on 12) The computer-implemented method of claim 12, wherein adjusting the weight on bit setpoint comprises: determining whether the weight on bit setpoint is outside of the target weight on bit range by at least a minimum threshold. ### Claim 14 (depends on 13) The computer-implemented method of claim 13, wherein adjusting the weight on bit setpoint further comprises: determining that the weight on bit setpoint is outside of the target weight on bit range by at least the minimum threshold; determining a difference between the weight on bit setpoint and a further minimum threshold; and adjusting the weight on bit setpoint based on the difference. ### Claim 15 (depends on 10) The computer-implemented method of claim 10, further comprising, prior to adjusting the weight on bit setpoint, determining whether adjusting the weight on bit setpoint would cause one or more of a torque limit, the differential pressure limit, a standpipe pressure limit, and a rate of penetration limit to be exceeded. ### Claim 16 A computer-readable medium having computer program code stored thereon and configured when executed by one or more processors to cause the one or more processors to perform a method for controlling a drilling operation, comprising: determining a difference between a differential pressure and a target differential pressure, wherein the target differential pressure is less than a differential pressure limit; and adjusting a weight on bit setpoint as a function of the difference between the differential pressure and the target differential pressure so as to adjust the differential pressure and thereby reduce the difference between the differential pressure and the target differential pressure, wherein adjusting the weight on bit setpoint comprises: determining a relationship between a weight on bit and the differential pressure; and adjusting the weight on bit setpoint based on the relationship, wherein adjusting the weight on bit setpoint based on the relationship comprises: determining a target weight on bit based on the relationship; determining an adjustment to be made to the weight on bit setpoint based on the target weight on bit; and adjusting the weight on bit setpoint based on the determined adjustment. ### Claim 17 (depends on 16) The computer-readable medium of claim 16, wherein determining the relationship comprises: obtaining a dataset comprising weight on bit measurements as a function of differential pressure measurements; and performing statistical analysis on the dataset. ### Claim 18 (depends on 17) The computer-readable medium of claim 17, wherein performing the statistical analysis comprises performing linear regression. ### Claim 19 (depends on 18) The computer-readable medium of claim 18, wherein the method further comprises, prior to adjusting the weight on bit setpoint, determining whether a slope of the output of the linear regression is within a preset range of slopes. ### Claim 20 (depends on 17) The computer-readable medium of claim 17, wherein the method further comprises: determining a lag between the weight on bit measurements and the differential pressure measurements; and adjusting the dataset based on the lag.