Controlling ramp up of a fluid pump

Patent metadata

Field	Value
Publication number	US-12264667-B2
Application number	US-202217649521-A
Country	US
Kind code	B2
Filing date	Jan 31, 2022
Priority date	Jan 31, 2022
Publication date	Apr 1, 2025
Grant date	Apr 1, 2025

Abstract

In some implementations, a controller may monitor, during a ramp up period of a fluid pump driven by a motor that is controlled by a variable frequency drive (VFD), an intake pressure of the fluid pump and a discharge pressure of the fluid pump. The controller may detect, based on monitoring the intake pressure and the discharge pressure, whether the intake pressure satisfies an intake pressure threshold or the discharge pressure satisfies a discharge pressure threshold. The controller may cause, via the VFD, reduction of a torque of the motor based on the intake pressure satisfying the intake pressure threshold or the discharge pressure satisfying the discharge pressure threshold.

First claim

What is claimed is:

1. A system for hydraulic fracturing, comprising:
a fluid pump;
a motor configured to drive the fluid pump;
a variable frequency drive (VFD) configured to control the motor; and
a controller configured to:
receive an operator input that indicates a setting for a maximum discharge pressure associated with the fluid pump;
monitor, during a ramp up period of the fluid pump, an intake pressure of the fluid pump, a discharge pressure of the fluid pump, a torque of the motor, and a flow rate associated with the fluid pump;
detect, based on monitoring the discharge pressure and the torque, whether the torque corresponds to a maximum torque that is based on the setting for the maximum discharge pressure associated with the fluid pump that was indicated by the operator input;
detect, based on monitoring the flow rate associated with the fluid pump, whether the flow rate is less than a flow rate set point; and
cause, via the VFD, reduction of the torque of the motor based on the torque corresponding to the maximum torque and the flow rate being less than the flow rate set point, the flow rate set point being associated with the maximum torque.

2. The system of claim 1 , wherein reduction of the torque of the motor is further caused based on at least one of the intake pressure satisfying an intake pressure threshold for a first threshold time period or the discharge pressure satisfying a discharge pressure threshold for a second threshold time period.

3. The system of claim 1 , wherein the controller is further configured to:
transmit a notification indicating a fault condition associated with the fluid pump based on the torque corresponding to the maximum torque.

4. The system of claim 1 , wherein the controller, to cause reduction of the torque of the motor, is configured to:
cause, via the VFD, adjustment to a speed of the motor.

5. The system of claim 1 , wherein the controller, to cause reduction of the torque of the motor, is configured to:
set a torque setting in a control mode for the VFD to a reduced torque value.

6. The system of claim 1 , wherein at least the fluid pump and the motor are mounted on a hydraulic fracturing trailer.

7. The system of claim 1 , wherein the intake pressure of the fluid pump is a suction pressure of the fluid pump.

8. The system of claim 1 , wherein the controller is further configured to:
determine the maximum torque for the motor, that achieves the maximum discharge pressure, based on a configuration, of a pump system that includes the fluid pump or the system for hydraulic fracturing, and using a look-up table, a torque curve, a physics-based estimation model, or an artificial intelligence model.

9. The system of claim 1 , wherein the flow rate set point is a first flow rate set point that is set when the torque corresponds to the maximum torque, the controller being further configured to set the flow rate set point to a second flow rate set point when the torque does not correspond to the maximum torque.

10. A method, comprising:
receiving an operator input that indicates a setting for a maximum discharge pressure associated with a fluid pump driven by a motor that is controlled by a variable frequency drive (VFD);
monitoring a torque of the motor during a ramp up period of the fluid pump during which a flow rate of the fluid pump increases, the ramp up period ending when the fluid pump reaches a commanded flow rate, a target flow rate, or a maximum flow rate;
detecting, based on monitoring the torque of the motor, whether the torque corresponds to a maximum torque that is based on the setting, for the maximum discharge pressure associated with the fluid pump for the ramp up period, indicated by the operator input; and
causing, via the VFD, reduction of the torque of the motor based on the torque corresponding to the maximum torque.

11. The method of claim 10 , wherein the torque of the motor is reduced to zero.

12. The method of claim 10 , wherein causing reduction of the torque of the motor comprises:
causing the VFD to vary at least one of an input frequency or an input voltage to the motor.

13. The method of claim 10 , wherein reduction of the torque of the motor is further caused based on at least one of an intake pressure of the fluid pump satisfying an intake pressure threshold for a first threshold time period or a discharge pressure of the fluid pump satisfying a discharge pressure threshold for a second threshold time period.

14. The method of claim 10 , further comprising:
transmitting a notification indicating a fault condition associated with the fluid pump based on the torque corresponding to the maximum torque.

15. The method of claim 10 , wherein the fluid pump is a hydraulic fracturing pump.

16. The method of claim 10 , further comprising:
monitoring a flow rate associated with the fluid pump;
detecting, based on monitoring the flow rate associated with the fluid pump, whether the flow rate is less than a flow rate set point; and
causing, via the VFD, reduction of the torque of the motor based on the torque corresponding to the maximum torque and the flow rate being less than the flow rate set point, the flow rate set point being associated with the maximum torque.

17. A controller, comprising:
one or more memories; and
one or more processors configured to:
obtain a setting, for a maximum discharge pressure associated with a fluid pump driven by a motor that is controlled by a variable frequency drive (VFD), that is based on an input;
detect, during a ramp up period of the fluid pump, that a torque of the motor corresponds to a maximum torque that is based on the setting for the maximum discharge pressure associated with the fluid pump and based on a configuration that includes one or more of a gear ratio of one or more of the fluid pump or the motor, a stroke length of the fluid pump, a bore diameter of the fluid pump, or a parasitic loss associated with the fluid pump; and
cause, via the VFD, reduction of the torque of the motor based on the torque of the motor corresponding to the maximum torque.

18. The controller of claim 17 , wherein the one or more processors are further configured to:
determine the maximum torque based on the setting for the maximum discharge pressure.

19. The controller of claim 17 , wherein the one or more processors, to cause reduction of the torque, are configured to:
cause reduction of the torque based on the torque of the motor corresponding to the maximum torque and based on one of:
an intake pressure of the fluid pump being less than an average intake pressure among a plurality of fluid pumps that include the fluid pump, or
a discharge pressure of the fluid pump being greater than an average discharge pressure among the plurality of fluid pumps.

20. The controller of claim 17 , wherein the controller is further configured to:
monitor a flow rate associated with the fluid pump;
detect, based on monitoring the flow rate associated with the fluid pump, whether the flow rate is less than a flow rate set point; and
cause, via the VFD, reduction of the torque of the motor based on the torque corresponding to the maximum torque and the flow rate being less than the flow rate set point, the flow rate set point being associated with the maximum torque.

Assignees

• Caterpillar Inc

Inventors

• Kabrich Todd Ryan
• Publes Andy
• Grimes Mark Francis
• He Yuesheng

Classifications

• F04B51/00

  Testing machines, pumps, or pumping installations · CPC title

• E21B43/2607 Primary

  Surface equipment specially adapted for fracturing operations · CPC title

• F04B2205/04

  Pressure in the outlet chamber · CPC title

• F04B2205/02

  Pressure in the inlet chamber · CPC title

• F04B2205/09

  Flow through the pump · CPC title