Systems and methods of optimized pump speed control to reduce cavitation, pulsation and load fluctuation

Abstract

The speed of a pump may be controlled to reduce cavitation and to reduce flow and pressure fluctuation in the pumped fluid. A system for pumping a fluid may comprise a pump, a primary mover coupled to the pump, and a controller coupled to the primary mover wherein the controller is programmed to control the primary mover so as to optimize a characteristic of the system. Pumping a fluid may comprise providing a pumping apparatus that comprises a pump, a primary mover which actuates the pump, and a controller which sends commands to the primary mover. One or more characteristics of the pumping apparatus may be utilized to modify the speed of the pump.

What is claimed is: 
     
         1 . A system for pumping a fluid, comprising:
 a pump;   a primary mover coupled to the pump; and   a controller coupled to the primary mover, wherein the controller is configured to cause the speed of the primary mover to fluctuate cyclically to optimize a first characteristic of the system.   
     
     
         2 . The system of  claim 1 , further comprising at least one sensor communicatively coupled to the controller, wherein the sensor is configured to monitor a second characteristic of the system. 
     
     
         3 . The system of  claim 2 , wherein the first characteristic and the second characteristic are the same. 
     
     
         4 . The system of  claim 2 , wherein at least one of the first characteristic and second characteristic comprises a fluid pressure, a fluid flow rate, a vibration, a force, a torque, a linear displacement, an angular displacement, a linear velocity, an angular velocity, a linear acceleration, or an angular acceleration. 
     
     
         5 . The system of  claim 2 , wherein the at least one sensor comprises at least one of a strain gauge, a flow meter, an accelerometer, a pressure sensor, a position sensor, a velocity sensor or an acoustic sensor. 
     
     
         6 . The system of  claim 1 , wherein the primary mover comprises an electric motor. 
     
     
         7 . The system of  claim 1 , wherein the primary mover comprises an internal combustion engine. 
     
     
         8 . The system of  claim 1 , wherein the primary mover is coupled to the pump by a drivetrain. 
     
     
         9 . A method for pumping a fluid, comprising:
 providing a pumping apparatus, wherein the pumping apparatus comprises a pump, a primary mover, and a controller, wherein the controller comprises a processor and a memory device, wherein the processor is programmed to send one or more commands to the primary mover;   actuating, by the primary mover, the pump;   modifying at least one of the one or more commands based, at least in part, on one or more characteristics of the pumping apparatus; and   sending at least one of the one or more modified commands to the primary mover to optimize at least one of the one or more characteristic of the pumping apparatus.   
     
     
         10 . The method of  claim 9 , wherein at least one of the one or more characteristics of the pumping apparatus comprises a fluid pressure, a fluid flow rate, a vibration of the pumping apparatus component, a force of a component of the pumping apparatus, a torque of the component, a linear displacement of the component, an angular displacement of the component, a linear velocity of the component, an angular velocity of the component, a linear acceleration of the component or an angular acceleration of the component. 
     
     
         11 . The method of  claim 9 , wherein the pumping apparatus comprises an electric motor. 
     
     
         12 . The method of  claim 9 , wherein the pumping apparatus comprises an internal combustion engine. 
     
     
         13 . The method of  claim 9 , further comprising sending one or more command signals to the primary mover to control a rotational speed of the pump, wherein controlling the rotational speed of the pump comprises fluctuating the rotational speed cyclically to optimize at least one of the one or more characteristics of the pumping apparatus. 
     
     
         14 . A method for pumping a fluid in a well operation, comprising:
 providing a pumping apparatus comprising: a pump, a primary mover mechanically coupled to the pump by a drive train such that the primary mover actuates the pump, a controller that sends commands to the primary mover, and a sensor coupled to the controller;   pumping the fluid downhole;   monitoring a first characteristic of the pumping apparatus with the sensor;   sending a signal to the controller indicative of a magnitude of the first characteristic;   generating a command signal to optimize a second characteristic of the pumping apparatus; and   sending the command signal to the primary mover, wherein the command signal causes a speed of the primary mover to fluctuate cyclically.   
     
     
         15 . The method of  claim 14 , wherein the first characteristic and the second characteristic are the same. 
     
     
         16 . The method of  claim 14 , further comprising monitoring a third characteristic, wherein the third characteristic comprises a fluid pressure, a fluid flow rate, a vibration of a pumping apparatus component, a position, a velocity, an acoustic or any combination thereof 
     
     
         17 . The method of  claim 14 , wherein the pumping apparatus comprises an electric motor. 
     
     
         18 . The method of  claim 14 , wherein the pumping apparatus comprises an internal combustion engine. 
     
     
         19 . The method of  claim 14 , further comprising sending a command to the primary mover to fluctuate cyclically a rotational speed of the pump to optimize the second characteristic of the pumping apparatus. 
     
     
         20 . The method of  claim 14 , wherein the first characteristic and the second characteristic are the vibration of the pumping apparatus.