Superconducting Current Limiter for Quench Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional quench protection systems for superconducting magnets rely on external current limiters and electrical wires through vacuum vessels, increasing costs and potentially compromising vacuum reliability, while they aim to manage quench events by spreading heat and limiting voltage and temperature within safe ranges.
Innovation Solution
A quench protection circuit with a superconducting current limiter in series with a quench heater assembly, thermally coupled to the superconducting coils, which transitions from a zero-resistance to a normal resistance state to control current flow and heat distribution during quench events, eliminating the need for external wiring by being integrated within the vacuum vessel.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional current limiters are arranged outside the vacuum vessel, then the quench protection function is achieved, but additional wiring through the vacuum vessel is required which increases cost and may adversely decrease vacuum reliability
Solution Approach 1:
The current limiter is merged with the quench heater assembly and both are integrated inside the vacuum vessel, eliminating the need for external wiring through the vacuum vessel. This consolidation reduces wiring complexity and potential vacuum leakage points while maintaining quench protection functionality.
Solution Approach 2:
A voltage blocker is introduced as an intermediary component in series with the quench heater assembly. The voltage blocker prevents voltage spikes during normal operation from damaging the quench heater, while allowing the quench protection circuit to function properly during quench events.
2Reliability
If quench protection devices quickly spread the normal zone to other portions of the coils, then the maximum temperature and voltage are limited to safe ranges, but the current flowing through the quench heater assembly may exceed maximum allowable current and damage the heater
Solution Approach 1:
The voltage blocker is pre-installed in series with the quench heater assembly to prevent overcurrent damage before it occurs. During normal operation, the voltage blocker blocks voltage spikes, and during quench events, it limits the current to safe levels, preventing damage to the quench heater while still enabling effective quench protection.
Solution Approach 2:
The voltage blocker acts as a protective cushion for the quench heater assembly, absorbing voltage spikes and limiting current flow before they can cause damage. This preliminary protection mechanism ensures the quench heater remains functional for its intended purpose without being damaged by excessive current.
3Reliability
If a voltage blocker is added in series with the quench heater assembly, then the quench heater is protected from voltage spikes, but the device complexity increases
Solution Approach 1:
The voltage blocker is merged into the quench protection circuit assembly and integrated inside the vacuum vessel along with the quench heater. This consolidation protects the quench heater from voltage spikes while avoiding the need for additional external components or wiring, thereby minimizing the increase in overall device complexity.
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
This solution effectively manages quench events by distributing heat evenly across the superconducting coils, preventing overheating and overcurrent damage, while maintaining vacuum integrity and reducing operational costs by eliminating external wiring.
Implementation Method 1
The circuit includes at least one quench heater assembly thermally coupled to the at least one coil
Implementation Method 2
The superconducting current limiter has a superconducting state with zero resistance, and a normal state with a normal resistance
Implementation Method 3
dump the magnetic energy into joule heat more evenly across the entire coils or magnet
Implementation Method 4
superconducting magnets conduct electricity without resistance as long as the magnets are maintained at a suitably low temperature
Data Source
AI summary
A superconducting magnet includes at least one superconducting coil and a quench protection circuit electrically coupled to said at least one coil in parallel. The circuit includes at least one quench heater assembly thermally coupled to the at least one coil, and at least one superconducting current limiter electrically connected in series with the at least one quench heater assembly. The superconducting current limiter has a superconducting state with zero resistance, and a normal state with a normal resistance to decrease an electric current flowing through the quench heater assembly.