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Optimized Unilateral Magnetic Resonance Sensor with Constant Gradient and Its Applications in Composite Insulators
Pan Guo1, Chenjie Yang1, Jiamin Wu2,3
1College of Physics and Electronic Engineering, Chongqing Normal University, Chongqing 401331, China.
Sensors (Basel, Switzerland)
|July 8, 2023
Summary
This study presents an optimized magnetic resonance sensor for assessing composite insulator aging in power grids. The new sensor effectively visualizes aging through T2 decay, aiding in grid maintenance.
Area of Science:
- Electrical Engineering
- Materials Science
- Physics
Background:
- Composite insulators are critical components in power grids, and their aging affects grid reliability.
- Assessing insulator aging is essential for preventing failures and ensuring grid stability.
- Current methods for assessing insulator aging may have limitations in precision and scope.
Purpose of the Study:
- To develop and optimize a unilateral magnetic resonance sensor for evaluating the aging of composite insulators.
- To enhance the magnetic field strength and radiofrequency (RF) field homogeneity for improved sensor performance.
- To demonstrate the sensor's capability in visualizing insulator aging using magnetic resonance techniques.
Main Methods:
- Optimization of a three-magnet array unilateral magnetic resonance sensor, focusing on magnetic field strength, RF field homogeneity, and gradient.
- Characterization of the sensor's magnetic field properties, including field strength, gradient, and uniformity.
- Application of the optimized sensor with the Carr-Purcell-Meiboom-Gill (CPMG) pulse sequence to composite insulator samples.
- Analysis of T2 distribution to visualize T2 decay in insulators with varying aging levels.
Main Results:
- An optimized unilateral magnetic resonance sensor was developed with a magnetic field strength of 139.74 mT and a uniformity of 0.75% over a 10 mm × 10 mm area.
- The sensor achieved a gradient of 2.318 T/m, enabling a hydrogen atomic nuclear magnetic resonance frequency of 5.95 MHz.
- The T2 distribution effectively visualized the T2 decay, correlating with different degrees of composite insulator aging.
Conclusions:
- The optimized unilateral magnetic resonance sensor is a viable tool for non-destructive assessment of composite insulator aging.
- The sensor's ability to visualize T2 decay provides valuable insights into the aging process of composite insulators.
- This technology can contribute to improved monitoring and maintenance strategies for power grid infrastructure.
Keywords:
aging assessmentcomposite insulatortransverse relaxation time (T2)unilateral magnetic resonance (UMR)More Related Videos
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