Progressing Cavity Pump Fluid Level Estimation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing pumping systems face challenges in accurately estimating and controlling fluid levels in wellbores without the need for in-well sensors, which are difficult to access and maintain, leading to increased costs and reduced system reliability.
Innovation Solution
A method and system that uses a progressing cavity pump coupled with an electric motor and a controller to determine fluid levels by recording pump torque and speed values in a look-up table, allowing for estimated fluid level determination without in-well sensors, and adjusting motor and pump parameters to maintain a predetermined fluid level.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If in-well sensors are used to measure fluid levels, then measurement precision is improved, but device complexity and maintenance difficulty increase
Solution Approach 1:
The patent extracts the measurement function from physical sensors inside the well and relocates it to a surface-based controller. The controller uses mathematical pump models and torque-speed measurements taken at the surface to infer fluid level, eliminating the need for downhole sensors and their associated installation and maintenance complexities.
Solution Approach 2:
The patent introduces mathematical pump models as an intermediary between the measurable parameters (torque, speed) and the desired measurement (fluid level). These models act as a mediator that translates easily obtainable surface measurements into accurate fluid level estimates without requiring direct physical sensing in the wellbore.
2Productivity
If in-well sensors are installed to control pump operations, then pump efficiency is improved, but installation and maintenance costs increase
Solution Approach 1:
The measurement and control functionality is extracted from the downhole environment and relocated to surface equipment. This eliminates the need for expensive sensor installation and maintenance operations in the wellbore, reducing overall system costs while maintaining pump efficiency through accurate fluid level control.
Solution Approach 2:
The system uses the pump's own operating parameters (torque and speed), which are already being measured for control purposes, to derive fluid level information. This self-service approach eliminates the need for separate sensing equipment, reducing both installation and operational costs.
3Measurement precision
If sensors are placed inside the wellbore, then fluid level control accuracy is improved, but system reliability decreases due to sensor exposure to harmful environments
Solution Approach 1:
The sensing function is extracted from the harsh downhole environment and relocated to surface-based equipment. The controller uses mathematical models and surface-measured parameters to achieve accurate fluid level control without exposing sensors to high temperatures, pressures, or corrosive conditions, thereby maintaining both accuracy and reliability.
Solution Approach 2:
Instead of directly measuring fluid level with physical sensors in the wellbore, the system creates a virtual model or copy of the pump system's behavior using mathematical models. This virtual representation allows accurate fluid level estimation without requiring physical presence in the harsh environment, preserving sensor reliability.
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
A method and apparatus for operating a pumping system includes the following: determining a motor operating parameter of a motor configured to drive a pump in a well; determining a pump operating parameter of the pump based on the motor operating parameter; operating the pump in a first mode to determine pump characteristics at a desired fluid level; generating first mode output data based on operation of the pump in the first mode; operating the pump in a second mode based on the first mode output data; determining an estimated fluid level in the well based on the motor operating parameter, the pump operating parameter and the first mode output data; and adjusting the pump speed based on the estimated fluid level in order to maintain a desired fluid level.