Reactive Acoustic Source Driver Circuit for Shear Slowness Logging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing acoustic logging methods, such as monopole and multipole acoustic logging, face limitations in accurately measuring shear slowness in fast formations, with monopole logging being unreliable and multipole logging being insensitive to variations in fast formations.
Innovation Solution
A system and method to drive a reactive acoustic source using a driver circuit with switching elements and a controller to selectively hold the source in different energy states, generating and propagating acoustic waves by transitioning between these states, thereby improving the reliability of shear slowness measurements across various formation types.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If monopole acoustic logging is used to measure shear slowness, then the measurement can be obtained in fast formations, but the measurement is unreliable because shear head waves cannot propagate in fast formations where shear slowness is less than mud slowness
Solution Approach 1:
The patent applies dynamic switching between monopole and multipole acoustic sources based on real-time detection of formation characteristics. The system dynamically adapts the acoustic source type to match the formation speed, using monopole for slow formations and multipole for fast formations, thereby ensuring reliable measurements across all formation types.
Solution Approach 2:
The system changes the operational parameters of the acoustic logging tool by switching between different acoustic source modes (monopole and multipole) and adjusting drilling parameters to control annular fluid flow. This allows the system to optimize measurements for different formation characteristics, particularly enabling reliable shear slowness measurement in fast formations by using multipole sources.
2Adaptability or versatility
If multipole acoustic logging is used to measure shear slowness, then measurements can be obtained in both fast and slow formations, but the sensitivity to shear slowness variations is reduced in fast formations
Solution Approach 1:
The system dynamically selects the acoustic source type based on detected formation characteristics. When slow formations are detected, monopole sources are activated for high-sensitivity measurements. When fast formations are detected, multipole sources are activated to maintain measurement capability, thereby optimizing both precision and adaptability across different formation types.
Solution Approach 2:
The system uses real-time feedback from initial acoustic measurements to determine formation type and subsequently selects the appropriate acoustic source mode. This feedback mechanism ensures that the system automatically adjusts its measurement approach to maintain optimal sensitivity and precision for the current formation conditions.
3Device complexity
If conventional acoustic sources are used in logging while drilling, then the apparatus is simple, but the ability to provide controlled current impulses for reliable measurements in varying formation types is insufficient
Solution Approach 1:
The patent implements a universal acoustic logging system that can perform both monopole and multipole acoustic logging functions within a single device. The system includes switching circuitry that enables the same physical apparatus to operate in different modes, providing reliable measurements across all formation types without requiring separate specialized equipment for each formation type.
Solution Approach 2:
The system incorporates dynamic control capabilities that allow real-time switching between monopole and multipole operational modes based on detected formation characteristics. This dynamic adaptability enables a single apparatus to maintain measurement reliability across varying formation types while avoiding the need for multiple separate systems.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution provides reliable and efficient current impulses to reactive acoustic sources, enabling accurate shear slowness measurements in both fast and slow formations, enhancing the reliability of acoustic logging in logging while drilling applications.
Implementation Method 1
reactive acoustic source to propagate an acoustic wave
Data Source
AI summary
Systems, methods, and apparatus to drive reactive loads are disclosed. An example apparatus to drive a reactive load includes a reactive component in circuit with the reactive load, a first switching element in circuit with the reactive load to selectively hold the reactive load in a first energy state and to selectively allow the reactive load to change from the first energy state to a second energy state, a second switching element in circuit with the reactive load to selectively hold the reactive load in the second energy state and to selectively allow the reactive load to change from the second energy state to the first energy state, and a controller to detect a current in the reactive load, and to control the first and second switching elements to hold the reactive load in the first or the second energy state when the current traverses a threshold.