Superconducting magnet with quench protection circuit

Abstract

The invention discloses a superconducting magnet quench protection circuit and a superconducting magnet with the same. The superconducting magnet quench protection circuit comprises a diode, an insulated-gate bipolar transistor and an energy leakage resistor, and the diode is serially connected with the insulated-gate bipolar transistor and then is parallelly connected with the energy leakage resistor; and the superconducting magnet comprises a body of the superconducting magnet, and is assembled with the superconducting magnet quench protection circuit, a quench detector, a current sensor, a short circuiter, and a current injection conductor. The protection circuit provides active quench protection for the superconducting magnet, and has sensitive quench judgment, and most of heat produced during the quench is dissipated on the energy leakage resistor outside the superconducting magnet so as to prevent the quick change of heat stress produced by a heater from causing the damage to the mechanical property of a superconductor, and prolong the service life of a superconducting line. The heat load of a cooling system produced during the quench is also greatly reduced, the time for returning to a superconducting state through the re-cooling after the quench is shortened, and the work efficiency of the whole machine is improved.

Description

technical field [0001] The invention relates to a superconducting magnet, in particular to a superconducting magnet with a quench protection circuit based on a large-capacity IGBT (Insulated-Gate Bipolar Transistor, insulated gate bipolar transistor). Background technique [0002] With the vigorous development of superconducting technology and superconducting materials, superconducting magnets have broad application prospects. Due to the advantages of small size, high current density, low energy consumption, and high field strength, superconducting magnets have been used more and more in important fields such as basic scientific research, medical care, transportation, and national defense industry in recent years. When a superconductor used in a superconducting magnet returns to a resistive state, it is called a quench. This may be caused by a parameter such as temperature, the strength of the external magnetic field or the density of the carrying current exceeding its crit...

AI Technical Summary

Problems solved by technology

[0006] The current protector or protection circuit has obvious disadvantages: First, most of the heat generated during the quench process is dissipated in the superconductor, and the rapid change of thermal stress will damage the mechanical properties of the superconductor

Excessive temperature will degrade the superconducting wire, causing the critical current to decrease, etc.

High temperatures can also damage the insulating material on the outer layer of superconducting wires

Second, superconducting materials generally work at a low temperature of about 10K. Using a heater will greatly increase the thermal load of the cooling system, prolong the time for re-entering the superconducting state after quenching, and reduce the overall machine efficiency.

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