JPH0745422A - Superconducting magnet device for magnetic levitation type railway - Google Patents

Abstract

PURPOSE:To restrain abnormal rise of a voltage generated when a superconducting coil is out of order during excitation or demagnetizing operation by making a circuit constitution switch element closed only when a superconducting coil is out of order during excitation or demagnetizing operation. CONSTITUTION:Permanent current switches 2a to 2f, protection resistors 3a to 3f installed on the car and diodes 4a to 4f are connected to each of one or more pairs of opposed right and left superconducting coils 1a to 1f and circuit constitution switch elements 5a to 5f are connected thereto to enable shortcircuiting of both ends of a superconducting coil. During excitation or demagnetization, when the superconducting coils 1a to 1f shift to normal conduction with the permanent current switches 2a to 2f opened, abnormal voltage rise generated at both ends of a superconducting coil is restrained by operation of the circuit constitution switches 5a to 5f corresponding to a superconducting coil which shortcircuits both ends of a superconducting coil.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a superconducting magnet device mounted on a magnetic levitation railway vehicle.

[0002]

2. Description of the Related Art FIG. 7 is a circuit diagram of a conventional magnetically levitated railway superconducting magnet device. Here, 1a to 1f
Is a superconducting coil, 2a to 2f are permanent current switches, and 3a.
˜3f is an on-vehicle protection resistor, 4a to 4f are on-vehicle diodes, 6a to 6c are current lead wires, 7a and 7b are excitation power cables, 8 is an excitation power supply, and 9 is a ground protection resistor. Reference numeral 10 is a ground-based diode.

The excitation power source 8 is disconnected when the superconducting coils 1a to 1f have been excited or demagnetized. When the excitation is completed, the current flowing through the superconducting coils 1a to 1f flows through the closed circuits formed by the superconducting coils 1a to 1f in the superconducting state and the permanent current switches 2a to 2f. Then, when an abnormality occurs in this circuit, the superconducting coils 1a to 1f and the permanent current switches 2a to 2f.
For protection purposes, on-board protection resistors 3a to 3f are installed in parallel with the permanent current switches 2a to 2f.
On-vehicle diodes 4a-4f and ground diode 1
0 is arranged for the purpose of preventing the shunt current from flowing through the on-vehicle arranged protection resistors 3a to 3f and the ground arranged protection resistor 9 during excitation. The ground protection resistor 9 shuts off the output part of the exciting power source 8 when an abnormality occurs in the superconducting coils 1a to 1f during excitation or demagnetization, but at this time, it is between the current lead wire 6a and the current lead wire 6b. It is arranged to prevent an overvoltage. further,
The permanent current switches 2a to 2f are thermal switches composed of superconducting wires, and have zero resistance in the closed state because they are in the superconducting state. To have.

When a magnetically levitated railway vehicle is running,
When an abnormality occurs in one of the superconducting coils 1a to 1f, it is necessary to quickly attenuate the current in the superconducting coils 1f to 1a facing it to maintain the electromagnetic force balance and improve the vehicle motion. Therefore, the resistance values of the on-vehicle disposition protective resistors 3a to 3f are such that when the currents of the superconducting coils 1a to 1f are commutated from the permanent current switches 2a to 2f to the on-vehicle disposition protective resistors 3a to 3f. 1
It must be large enough to induce normal conduction transition in f.

To excite the superconducting magnet, the permanent current switches 2a to 2f are energized in an open state, a predetermined current is passed through the superconducting coils 1a to 1f, and then the permanent current switches 2a to 2f are closed. Thereby, the superconducting coil 1a
The current of 1f is in the permanent current mode after the excitation power source 8 is disconnected, and the current continues to flow inside to keep the strong magnet.

When demagnetizing the superconducting magnet, the superconducting coils 1a to 1f in the permanent current mode are
Energization is started from the excitation power source 8 with the permanent current switches 2a to 2f closed, and the current is increased to the current value flowing in the superconducting coils 1a to 1f.
Open ~ 2f and lower to zero amps. This eliminates the strong magnetic force of superconducting coils 1a-1f.

[0007]

According to the prior art,
The on-board protective resistor has such a value that the superconducting coil causes a normal conduction transition when the current of the superconducting coil is commutated from the permanent current switch to the on-board protective resistor. It is incorporated for the purpose of blocking the shunt current to the onboard protection resistor during excitation. Therefore, when one or more superconducting coils cause an abnormality during the excitation or degaussing operation and transition to normal conduction occurs, an abnormal voltage rise occurs at both ends of the superconducting coils, and the superconducting magnet device is damaged. was there. The present invention aims to solve the above problems, and suppresses an abnormal voltage rise occurring at both ends of the superconducting coil even when the superconducting coil causes an abnormality during the excitation or degaussing operation and changes to the normal conducting state. To provide a superconducting magnet device.

[0008]

[Means for Solving the Problems] Claim 1 in the present invention
In the superconducting magnet device, the permanent current switch, the on-vehicle protection resistor and the diode are connected to each of the pair of left and right superconducting coils facing each other, and the switch element for circuit configuration is connected to this so that both ends of the superconducting coil can be short-circuited. It is a connected circuit. When an abnormality occurs in the current or voltage of the superconducting coil and the current of the superconducting coil is commutated from the permanent current switch to the on-board protective resistor, the on-vehicle protective resistor only causes the superconducting coil to change to the normal conducting state. When the permanent current switch is open and the superconducting coil undergoes normal conduction transition during excitation or degaussing, the switch element for circuit configuration corresponding to the superconducting coil operates to short-circuit both ends of the superconducting coil. By doing so, it is possible to suppress an abnormal voltage rise occurring at both ends of the superconducting coil. The superconducting magnet device according to a second aspect of the present invention is different from the superconducting magnet device according to the first aspect in that an electrode of a switch as a circuit configuration switch element is arranged in advance in an inert gas at a minute distance, and the electrodes are fixed between the electrodes. When a voltage equal to or higher than the value is generated, an element having a circuit configuration by discharging is used. The superconducting magnet device according to a third aspect of the present invention is different from the superconducting magnet device according to the first aspect in that the electrodes of the switch serving as the switch elements for circuit configuration are previously arranged in the air with a minute distance, and a certain value or more is provided between the electrodes. When a voltage of 1 is generated, an element having a circuit configuration by discharging is used.

[0009]

In the superconducting magnet device according to the present invention, the switch element for circuit configuration is closed only when an abnormality occurs in the superconducting coil during the excitation or degaussing work, and the abnormality occurs in the superconducting coil during the excitation or degaussing work. It is possible to suppress an abnormal rise in voltage that occurs when

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a magnetic levitation type superconducting magnet apparatus for a railway according to the present invention, in which an electrode of a switch as a switch element for circuit configuration is arranged in advance in an inert gas with a minute distance, and a certain value or more is provided between the electrodes. FIG. 6 is a circuit diagram of an embodiment in which a circuit is configured by discharging when a voltage of 1 is generated. FIG. 2 is a circuit diagram showing a current during the excitation work of the superconducting coil in the superconducting magnet device of FIG. FIG. 3 shows FIG.
FIG. 6 is a circuit diagram showing a current when the superconducting coil undergoes normal conduction transition during the operation of exciting the superconducting coil in the superconducting magnet device of FIG. FIG. 4 is a circuit diagram showing a current when one superconducting coil makes a transition to normal conduction when the superconducting coil in the superconducting magnet device of FIG. 1 is excited and in a state of a permanent current mode. FIG. 5 is a view of a superconducting magnet device for a magnetically levitated railway according to the present invention, in which a switch electrode as a circuit configuration switch element is arranged in advance in the air with a minute distance, and when a voltage of a certain value or more is generated between the electrodes. It is a circuit diagram of an example using what constitutes a circuit by discharge. FIG. 6 is a circuit diagram of an embodiment of a magnetic levitation railway superconducting magnet device according to the present invention in which a contactor is used as a circuit configuration switch element to short-circuit a circuit in response to an external command. Here, 1a to 1f are superconducting coils, 2a to 2f are permanent current switches, 3a to 3f are on-vehicle arranged protection resistors, 4a to 4f are on-vehicle arranged diodes, 5
a to 5f are switching elements for circuit configuration, 6a to 6c are current lead wires, 7a and 7b are power cables for excitation, 8 is a power source for excitation, 9 is a protective resistor placed on the ground, and 10 is a diode placed on the ground.

An embodiment of a magnetically levitated railway superconducting magnet device according to the present invention will be described with reference to FIG. The voltage at which the switching element for this circuit configuration constitutes the circuit, that is, the discharge start voltage is set to a voltage generated at both ends of each of the superconducting coils 1a to 1f during normal excitation or degaussing work, or a permanent current mode. Superconducting coils 1a-1f
And a persistent current switch 2a to 2f, the persistent current switch 2a
2f is a value higher than the voltage generated across both ends of the persistent current switches 2a to 2f which are in the open state when one of the superconducting coils 2a to 2f is in the open state due to the normal conduction transition, and the superconducting coil 1a.
.About.1f and the persistent current switches 2a to 2f need to be lower than the voltage at which they burn out or melt or the voltage at which the discharge phenomenon occurs inside the superconducting magnet device.

The mechanism of the present invention will be described below with reference to some drawings. When exciting the superconducting coil, since the permanent current switches 2a to 2f are opened in advance in a finite resistance state, most of the exciting current flows through the superconducting coils 1a to 1f as shown in FIG. At this time, since the exciting power source 8 is energized at a relatively low rate of current increase, the superconducting coil 1
With the voltage generated at both ends of each of a to 1f, the circuit configuration switch elements 5a to 5f maintain the open state, the circuit connecting each end of each of the superconducting coils 1a to 1f is not formed, and the superconducting magnet device is normally excited. You can do it.

Next, consider a case where an abnormality occurs in the current or voltage of the superconducting coils 1a to 1f during excitation. For example, in FIG.
As shown in, the energizing current value from the excitation power source 8 is 500
If the superconducting coil 1a undergoes normal conduction transition at the time of A,
Immediately after the transition, the energy stored in the superconducting coil 1a until then was attenuated by the circuit I shunting to the permanent current switch 2a and the onboard protection resistor 3a, and stored in the other superconducting coils 1b to 1f. Energy is attenuated in the circuit II including the ground protection resistor 9, the ground diode 10, and the permanent current switch 2a.
At this time, the excitation power source 8 has already detected the abnormality and has shut itself off. In the persistent current switch 2a, the circuit I and the circuit II
Since the directions of the currents are reversed, they cancel each other, and no abnormal voltage rise occurs at both ends of the permanent current switch 2a.

However, since the superconducting coil 1a of the circuit I undergoes normal conduction transition, the current decay speed is faster than that of the circuit II. Therefore, the current flowing through the permanent current switch 2a gradually increases, and the voltage generated across the current also increases. For example, the permanent current switch 2a
If the open resistance of ~ 2f is 50Ω and the current flowing through the permanent current switch 2a increases to 10 A, 500 V
Will occur at both ends. However, if the discharge start voltage of the circuit configuration switch elements 5a to 5f is, for example, 350V, the voltage across the permanent current switch 2a is 35V.
When the voltage reaches 0V, the switching element 5a for circuit configuration starts discharging to connect both ends of the permanent current switch 2a, so that the voltage across the permanent current switch 2a does not rise to 500V as described above. Further, the switch elements 5a to 5f for this circuit configuration are the superconducting coils 1a to
Since the circuit of 1f is detected automatically and the circuit is automatically constructed, a new controller for the closing command is not required.

The above contents are the same even during the degaussing operation.

Next, when the magnetic levitation railway vehicle is excited and in the permanent current mode, and the power source for excitation is disconnected, for example, as shown in FIG. 4, the persistent current switch 2a undergoes normal conduction transition or superconducting coil. Assuming that the permanent current switch 2a also transits to the normal conduction state at the same time that the 1a transitions to the superconducting state, the current value flowing in the superconducting coil 1a in the persistent current mode is set to 500A, and the resistance value of the vehicle-mounted protection resistor 3a is set to 0. When it is set to 0.6Ω, a voltage of 300V is initially generated across the permanent current switch 2a. However, since the circuit configuration switch elements 5a to 5f have not reached the discharge start voltage of 350 V, the circuit configuration switch elements 5a do not operate, and the energy stored in the superconducting coil 1a is consumed by the on-board protection resistor 3a. You can

FIG. 5 shows a magnetic levitation railway superconducting magnet device according to the present invention, in which electrodes of a switch serving as a switch element for circuit configuration are arranged in advance in the air at a minute distance, and a predetermined value or more is provided between the electrodes. This is an embodiment in the case of forming a circuit by discharging when a voltage is generated. In this case as well, the setting conditions of the voltage at which the circuit configuration switch elements 5a to 5f configure the circuit, that is, the discharge start voltage, are the superconducting coils 1a to 1 during normal excitation or degaussing work.
In the state where the voltage generated at both ends of f and the permanent current mode flow through the closed circuit composed of a pair of superconducting coils 1a to 1f and permanent current switches 2a to 2f,
The value is higher than the voltage generated at both ends of the persistent current switches 2a to 2f when any of the persistent current switches 2a to 2f is in the open state due to the normal conduction transition, and the superconducting coils 1a to 1f and the persistent current switch. It is necessary that the voltage of 2a to 2f is lower than the voltage at which burnout or fusing occurs or the voltage at which the discharge phenomenon occurs inside the superconducting magnet device. As a result, the same operation as that in FIG. 1 is performed in FIG. 5, and a control device for operating the switch is not required.

FIG. 6 shows an embodiment of the magnetic levitation type superconducting magnet device for railway according to the present invention, in which a contactor is used as a switch element for circuit construction. In this case, the operation is similar to that of FIG. 1, but since the circuit configuration is not an electric discharge of the switch itself but an external command, it is possible to control the voltage generated across the permanent current switches 2a to 2f at the time of an abnormality. Is.

The ground-mounted diode 10 shown in FIGS. 1, 5 and 6 is a switch element 5 for circuit configuration in consideration of operating voltage.
It is possible to transfer to a to 5f.

In the magnetically levitated railway superconducting magnet device according to the present invention, when one or more superconducting coils undergo normal conduction transition during the excitation or degaussing work of the superconducting coil, an abnormal phenomenon occurs at both ends of the superconducting coil. It is possible to suppress the voltage rise, and it is possible to eliminate the influence on the superconducting magnet device due to the abnormal voltage rise.

[Brief description of drawings]

FIG. 1 is a circuit diagram of an embodiment of a magnetic levitation type superconducting magnet device for a railway according to the present invention, in which electrodes of a switch are arranged in advance in an inert gas at a minute distance as a switch element.

FIG. 2 is a circuit diagram showing a current during an exciting operation of a superconducting coil in the superconducting magnet device of FIG.

FIG. 3 is a circuit diagram showing a current when the superconducting coil undergoes normal conduction transition during an operation of exciting the superconducting coil in the superconducting magnet device of FIG.

FIG. 4 is a circuit diagram showing a current when one superconducting coil undergoes normal conduction transition when the superconducting coil in the superconducting magnet device of FIG. 1 is excited and in a state of a permanent current mode.

FIG. 5 is an embodiment of a magnetic levitation railway superconducting magnet device according to the present invention, in which electrodes of a switch as a circuit configuration switch element are arranged in air at a minute distance in advance, and a voltage of a certain value or more is applied between the electrodes. It is a circuit diagram in the case of forming a circuit by discharge when it occurs.

FIG. 6 is a circuit diagram in the case where a contactor is used as a switch element for circuit configuration in an embodiment of a magnetic levitation railway superconducting magnet device according to the present invention.

FIG. 7 is a circuit diagram of a conventional magnetically levitated railway superconducting magnet device.

[Explanation of symbols]

 1a to 1f Superconducting coil 2a to 2f Permanent current switch 3a to 3f On-board arrangement protection resistor 4a to 4f On-board diode 5a to 5f Circuit configuration switch element 6a to 6c Current lead wire 7a, 7b Excitation power supply cable 8 Excitation Power supply 9 Ground protection resistor 10 Ground diode

Claims (3)

[Claims] 1. A superconducting magnet device comprising a superconducting coil, a permanent current switch, a vehicle-mounted protective resistor, and a circuit-forming switch element, which is mounted on a magnetic levitation railway vehicle. Each of which is connected to a permanent current switch, a vehicle-mounted protective resistor, and a diode, and a circuit configuration switch element connected so that both ends of the superconducting coil can be short-circuited. When an abnormality occurs in the superconducting coil and the current of the superconducting coil is diverted from the permanent current switch to the on-board locating resistor, the on-board locating resistor only causes the superconducting coil to undergo normal conduction transition. Has a value, and when the superconducting coil is excited or degaussed, the superconducting coil is transferred to the normal conducting state with the persistent current switch open The corresponding switch element for circuit configuration operates to short-circuit both ends of the superconducting coil, whereby the switch element for circuit configuration suppresses an abnormal voltage rise occurring at both ends of the superconducting coil. Magnetically levitated railway superconducting magnet device. 2. The superconducting magnet device according to claim 1, wherein electrodes of a switch serving as the switch element for circuit configuration are previously arranged in an inert gas at a minute distance, and a voltage of a certain value or more is generated between the electrodes. In this case, the magnetic levitation type superconducting magnet device for a railway according to claim 1, wherein an abnormal voltage rise occurring at both ends of the superconducting coil is suppressed by using an element having a circuit configuration by discharge. 3. The superconducting magnet device according to claim 1, wherein the electrodes of the switch serving as the switch element for circuit configuration are previously arranged in the air at a minute distance, and when a voltage of a certain value or more is generated between the electrodes. The magnetic levitation type superconducting magnet device for a railway according to claim 1, wherein an abnormal voltage rise generated at both ends of the superconducting coil is suppressed by using an element having a circuit configuration by discharge.