Autonomous annular pressure control assembly for perforation event

1. A method of perforating a casing string that extends within a wellbore, the method comprising:

measuring downhole pressure within the casing string;

firing a perforation gun that is positioned within the casing string to increase the downhole pressure within the casing string; and

adjusting the downhole pressure based on the measured downhole pressure;

wherein adjusting the downhole pressure comprises actuating a first pressure generator;

wherein the first pressure generator comprises at least one of:

a pressure reducer; and

a pressure increaser; and

wherein actuating the first pressure generator comprises at least one of:

actuating the pressure reducer after the measured downhole pressure is at or exceeds a maximum overbalance pressure;

actuating the pressure increaser after the measured downhole pressure is at or exceeds a maximum underbalance pressure;

actuating the pressure reducer after the measured downhole pressure reaches a peak measured overbalance pressure; and

actuating the pressure increaser after the measured downhole pressure reaches a peak measured underbalance pressure.

2. The method of claim 1 ,

wherein actuating the first pressure generator comprises at least one of:

actuating the pressure reducer after the measured downhole pressure is at or exceeds the maximum overbalance pressure; and

actuating the pressure increaser after the measured downhole pressure is at or exceeds the maximum underbalance pressure.

3. The method of claim 1 ,

wherein actuating the first pressure generator comprises at least one of:

actuating the pressure reducer after the measured downhole pressure reaches the peak measured overbalance pressure; and

actuating the pressure increaser after the measured downhole pressure reaches the peak measured underbalance pressure.

4. The method of claim 1 , wherein the method further comprises:

storing a reference time-pressure profile within a tool that is positioned within the casing string;

continuing to measure the downhole pressure within the casing string over a period of time to form a dynamic time-pressure profile;

identifying a first measured pressure associated with a first instance of time within the dynamic time-pressure profile; and

determining a first difference between the first measured pressure and a first reference pressure associated with the first instance of time within the reference time-pressure profile;

wherein actuating the first pressure generator is further based on the first determined difference.

5. The method of claim 4 , wherein the method further comprises:

identifying a second measured pressure associated with a second instance of time within the dynamic time-pressure profile; and

determining a second difference between the second measured pressure and a second reference pressure associated with the second instance of time within the reference time-pressure profile;

wherein adjusting the downhole pressure further comprises actuating a second pressure generator; and

wherein actuating the second pressure generator is based on the second determined difference.

6. The method of claim 1 ,

wherein adjusting the downhole pressure based on the measured downhole pressure further comprises actuating a second pressure generator;

wherein the first pressure generator is a pressure reducer; and

wherein the second pressure generator is a pressure increaser.

7. The method of claim 6 ,

wherein actuating the first pressure generator results in a pressure underbalance within the casing string; and

wherein actuating the second pressure generator results in a pressure overbalance within the casing string.

8. The method of claim 1 , further comprising:

extending a feedback control loop within the casing string;

receiving the measured pressure at a controller of the feedback control loop;

comparing, using the controller, the measured pressure with a reference pressure that is stored within the controller; and

sending a signal from the controller to the first pressure generator;

wherein actuating the first pressure generator is in response to the signal.

9. A method of controlling a dynamic time-pressure profile associated with a perforation event, the method comprising:

extending a perforation assembly within a casing string;

firing a perforation gun of the perforation assembly;

measuring, using a sensor of the perforation assembly, pressure within the casing string, wherein the measured pressure forms the dynamic time-pressure profile;

identifying a first measured pressure within the dynamic time-pressure profile;

identifying, using a controller of the perforation assembly, a first difference between the first measured pressure and a first reference pressure; and

adjusting, using a first pressure generator of the perforation assembly, the pressure in response to the first difference to control the dynamic time-pressure profile;

wherein the sensor, the controller, and the first pressure generator provide a feedback control loop.

10. The method of claim 9 , the method further comprising:

identifying a second measured pressure within the dynamic time-pressure profile;

identifying, using the controller, a second difference between the second measured pressure and a second reference pressure; and

adjusting, using a second pressure generator of the perforation assembly, the pressure in response to the second difference to control the dynamic time-pressure profile.

11. The method of claim 9 , wherein adjusting the pressure, using the first pressure generator of the perforation assembly, in response to the first difference comprises actuating a pressure reducer to create a pressure underbalance in the casing string.

12. The method of claim 9 , wherein adjusting the pressure, using the first pressure generator of the perforation assembly, in response to the first difference comprises actuating a pressure increaser to create a pressure overbalance within the casing string.

13. The method of claim 9 ,

wherein the first reference pressure is a time-dependent reference pressure; and

wherein the first reference pressure is one reference pressure from a plurality of reference pressures that form a reference time-pressure profile.

14. The method of claim 13 , further comprising selecting, while the perforation assembly extends within the casting string, the reference time-pressure profile from a plurality of time-pressure profiles;

wherein selecting the reference time-pressure profile is based on the first measured pressure.

15. An apparatus for controlling a dynamic time-pressure profile associated with a perforation event, the apparatus comprising:

a downhole tool comprising:

a controller;

a pressure sensor in communication with the controller to provide feedback to the controller; and

a first pressure generator in communication with the controller;

wherein the first pressure generator, the pressure sensor, and the controller provide a feedback control loop;

wherein the controller comprises a computer readable medium operably coupled thereto, the computer readable medium storing a reference time-pressure profile;

wherein the controller is configured to determine a difference between a measured pressure from the pressure sensor and a reference pressure within the reference time-pressure profile, and send a signal to the first pressure generator based on the difference; and

wherein the first pressure generator is configured to actuate in response to the signal.

16. The apparatus of claim 15 , wherein the tool further comprises a perforation gun.

17. The apparatus of claim 15 , wherein the tool further comprises a second pressure generator.

18. The apparatus of claim 17 ,

wherein the first pressure generator is a one of:

a pressure decreaser; and

a pressure increaser; and

wherein the second pressure generator is the other of:

the pressure decreaser; and

the pressure increaser.

19. The apparatus of claim 15 , wherein the sensor is one of a mechanical pressure sensor and an electrical pressure sensor.