Methods, systems, and computer-readable media for performing automated drilling of a wellbore

A non-transitory 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, wherein determining the relationship comprises:
• obtaining a dataset comprising weight on bit measurements as a function of differential pressure measurements;
• determining a lag between the weight on bit measurements and the differential pressure measurements;
• adjusting the dataset based on the lag;
• and
• performing statistical analysis on the adjusted dataset to determine the relationship;
• and
• adjusting the weight on bit setpoint based on the relationship.

A system comprising:

• a drill string comprising a bottom hole assembly including a drill bit;
• a drawworks operable to control a weight applied to the drill bit;
• and
• a differential pressure manager comprising computer-readable memory and one or more processors, wherein the compute-readable memory comprises computer program code stored thereon and configured, when executed by the one or more processors, to cause the one or more processors to perform a 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, wherein determining the relationship comprises:
• obtaining a dataset comprising weight on bit measurements as a function of differential pressure measurements;
• determining a lag between the weight on bit measurements and the differential pressure measurements;
• adjusting the dataset based on the lag;
• and
• performing statistical analysis on the adjusted dataset to determine the relationship;
• and
• adjusting the weight on bit setpoint based on the relationship.