Superconducting Magnet Status Detection via Repulsive Force Sensor
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional MRI systems without liquid helium immersion for the persistent current switch (PCS) face challenges in determining the superconducting status of the superconducting magnet system, leading to potential delays in magnet energization and imaging procedures.
Innovation Solution
A system and method utilizing a sensor with a magnet that generates a repulsive electromagnetic force to switch between electrical coupling and disconnection states based on the superconducting status of the magnet, allowing accurate detection of the superconducting state in real-time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the PCS is not immersed in liquid helium to simplify the system, then device complexity is reduced, but the time required to cool the PCS increases significantly
Solution Approach 1:
The system performs preliminary cooling of the PCS using the external refrigeration system before attempting to energize the superconducting magnet. The controller monitors temperature sensors to determine when the PCS has reached the critical temperature threshold, ensuring the PCS is pre-cooled and ready for superconducting operation, thereby reducing the overall time penalty of not using liquid helium immersion
2Measurement precision
If temperature sensors are used to determine superconducting status, then measurement capability is provided, but cost increases and accuracy is reduced due to gradient temperatures
Solution Approach 1:
The patent introduces an intermediary detection system that uses a test signal approach instead of direct temperature sensing. A test current is applied to the PCS and the voltage response is measured; when the PCS transitions to superconducting state, the resistance drops to near zero, causing a characteristic voltage change that indicates superconducting status. This intermediary electrical measurement method avoids the problems of temperature gradient sensing while providing accurate, real-time detection of the superconducting transition
3Ease of manufacture
If the PCS is cooled by external refrigeration system, then liquid helium immersion is eliminated, but the time to reach superconducting state increases
Solution Approach 1:
The controller continuously monitors the voltage across the PCS during the cooling and energization process. When the voltage drops to below a threshold value, indicating the PCS has transitioned to superconducting state, the controller automatically proceeds with magnet energization. This feedback mechanism eliminates waiting delays by triggering energization immediately upon detecting superconducting transition, maximizing productivity while maintaining the ease of manufacture benefits of external refrigeration
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
Enables precise and timely determination of the superconducting status of the magnet, ensuring proper energization and reducing delays in MRI operations, thereby improving the efficiency and reliability of sealed MRI systems.
Implementation Method 1
the sensor switches between the first state and the second state based on a repulsive electromagnetic force generated between the magnet and superconducting status of superconducting coil elements
Data Source
Figure 1~2
Figure 3A~3B
Figure 4A~4B
AI summary
A system and method for detecting the superconducting status of a superconducting magnet used in magnet resonance imaging (MRI) are disclosed. The system comprises a sensor (208) having a magnet (230) positionable in a proximity of one or more superconducting coil elements (204) of the superconducting magnet. The sensor is configured to shift between a first state and a second state based on a repulsive force generated between the magnet and the one or more superconducting coil elements, wherein the second state is indicative that the one or more superconducting coil elements have reached superconducting status and wherein the first state is indicative that the one or more superconducting coil elements have not reached the superconducting status. The output of the sensor may control the operation of a persistent current switch (206) and connecting or disconnecting of a power supply (210) associated to the superconducting magnet.