Automatic Detection of Resonance Frequency of a Downhole System

Abstract

A system includes a downhole tool adapted to be run at plural operating frequencies, a drive system to control an operating frequency of the downhole tool, and a controller to control the drive system to, in a test procedure, vary the operating frequency of the downhole tool. The controller automatically detects a resonance frequency of the downhole tool in the test procedure.

1 . An apparatus comprising: a downhole system adapted to be run at plural operating frequencies; a drive system to control an operating frequency of the downhole tool; and a controller to control the drive system to, in a test procedure, vary the operating frequency of the downhole system, the controller to automatically detect a resonance frequency of the downhole system in the test procedure.  
   
   
       2 . The apparatus of  claim 1 , the controller to further set the detected resonance frequency as a frequency to avoid in the drive system.  
   
   
       3 . The apparatus of  claim 2 , wherein the controller sets the detected resonance frequency to avoid by setting the resonance frequency as a jump frequency in the drive system.  
   
   
       4 . The apparatus of  claim 1 , wherein the controller comprises a central processing unit and software executable on the central processing unit, the software executable to perform the control and detect tasks.  
   
   
       5 . The apparatus of  claim 1 , wherein the downhole system comprises a pump adapted to be run at the plural operating frequencies.  
   
   
       6 . The apparatus of  claim 5 , wherein the pump comprises an electrical submersible pump.  
   
   
       7 . The apparatus of  claim 1 , further comprising a vibration sensor to detect vibration of the downhole system during the test procedure, the controller to receive data from the vibration sensor for detecting the resonance frequency.  
   
   
       8 . The apparatus of  claim 7 , the controller to perform the test procedure by causing the operating frequency of the downhole tool to be varied across a predefined frequency range.  
   
   
       9 . The apparatus of  claim 1 , further comprising at least one of a user station and a local user interface of the controller to display a result of the test procedure.  
   
   
       10 . A method to perform a test procedure in a downhole tool deployed in a wellbore, comprising: varying, in response to control of a control module, an operating frequency of the downhole tool across a predefined frequency range in the test procedure; receiving, by the control module, vibration data of the downhole tool as the operating frequency of the downhole tool is varied across the predefined frequency range; and automatically determining, by the control module, a resonance frequency of the downhole tool based on the vibration data.  
   
   
       11 . The method of  claim 10 , further comprising displaying a result of the test procedure on a user interface.  
   
   
       12 . The method of  claim 10 , further comprising setting, at a drive system that controls the operating frequency of the downhole tool, a frequency to avoid based on the determined resonance frequency.  
   
   
       13 . The method of  claim 10 , wherein varying the operating frequency of the downhole tool comprises varying the operating frequency of an electrical submersible pump.  
   
   
       14 . The method of  claim 10 , wherein receiving vibration data of the downhole tool comprises receiving vibration data from a vibration sensor in the downhole tool.  
   
   
       15 . The method of  claim 14 , further comprising receiving a minimum operating frequency and a maximum operating frequency that defines the predefined frequency range.  
   
   
       16 . The method of  claim 15 , further comprising generating the maximum operating frequency based at least in part on flow rate information or pressure information received from one or more sensors in the downhole tool.  
   
   
       17 . An article comprising at least one storage medium containing instructions that when executed cause a control module to: control a drive system to vary an operating frequency of a downhole tool across a predefined frequency range during a test procedure; and determine a resonance frequency of the downhole tool based on information received from the downhole tool during the test procedure as the operating frequency of the downhole tool is varied across the predefined frequency range.  
   
   
       18 . The article of  claim 17 , wherein the instructions when executed cause the control module to further receive vibration data from a vibration sensor of the downhole tool, wherein determining the resonance frequency of the downhole tool is based on the vibration data.  
   
   
       19 . The article of  claim 17 , wherein the instructions when executed further cause the control module to generate a maximum operating frequency of the predefined frequency range, the maximum operating frequency generated based on flow rate information or pressure information received from one or more sensors of the downhole tool.  
   
   
       20 . The article of  claim 19 , wherein generating the maximum operating frequency is further based on horsepower information of the downhole tool.  
   
   
       21 . The article of  claim 17 , wherein controlling the drive system to vary the operating frequency of the downhole tool comprises controlling the drive system to vary the operating frequency of a pump assembly.