JPS6349888B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a superconducting device such as a magnetic levitation train that simultaneously excites a plurality of superconducting magnets.

A conventional device of this type is shown in the electrical circuit diagram of FIG.

In the figure, 1 is an excitation power supply device composed of a DC power supply 2 and a wire breaker 3, etc., 4 is a connection terminal, 5 is a superconducting magnet, 6 is a persistent current switch, 7 is a protective resistor, 8 is a diode, and 9 is a A cryostat consisting of the superconducting magnet, persistent current switch, protective resistor, diode, etc., 1
0 is a floating body of a magnetic levitation train composed of a plurality of cryostats 9 and the like. It should be noted that since all of the plurality of cryostats 9 are composed of the same parts, only one is given a reference numeral and its operation etc. will be explained, and the description of the others will be omitted.

Generally, under normal conditions, a circulating current continues to flow through the superconducting magnet 5 inside the cryostat 9 due to the short-circuited persistent current switch 6, forming a permanent magnet.
is separated from the excitation power supply device 1 on the ground side and the connection terminal 4, and can be moved freely.

On the other hand, during initial energization or when changing the current value for inspection, the floating body 10 is connected to the excitation power supply 1 as shown in the circuit diagram of FIG. When energizing the superconducting magnet 5, open the persistent current switch 6, turn on the circuit breaker 3 of the excitation power supply 1, and then increase the current of the DC power supply 2 to close the connection terminal 4. A current flows through it in the direction of the arrow, and the superconducting magnet is excited.
At this time, since the polarity of the diode 8 is opposite to the direction of the current, no current flows through the protective resistor 7. At this time, if any of the superconducting magnets causes superconducting breakdown, in order to protect the DC power source 2, the shield breaker 3 is disconnected to isolate the DC power source 2. The electric energy stored in the superconducting coil 5 flows into the protective resistor 7 via the diode 8 because the direction in which the emission current flows and the polarity of the diode 8 are in the forward direction. Heat is consumed.

The conventional device is configured as described above, so it requires a large protective resistor to dissipate all of the energy stored in the superconducting magnet, and a large-capacity diode to withstand the maximum current. Loading these on a floating body had the disadvantage of increasing the overall weight.

This invention was made in order to eliminate the drawbacks of the conventional ones as described above, and it involves installing an external protection resistor and a short circuit switch on the ground excitation power supply side, and interlocking it with the operation of the breaker. By doing so, the purpose is to eliminate the diode on the floating body side that was conventionally required, and to make the protective resistor smaller.

An embodiment of the present invention will be described below based on the electrical circuit diagram shown in FIG. In order to avoid duplication in the drawings, the same parts as in FIG. 1 are given the same reference numerals and their explanations will be omitted. In this figure 2, 7
11 is an external protection resistor, and 12 is a short-circuit switch. Note that the resistance value of the external protection resistor 11 is smaller than the total resistance value of the protection resistors 7.

In this structure, when energizing the superconducting magnet 5, first, the persistent current switch 6 is opened, the shield breaker 3 is closed, and the short circuit switch 12 is opened, and then the DC power supply 2 is turned on. increase the current. At this time, a part of the current flows through the protection resistor 7, but this value is small because the resistance value of the protection resistor 7 is increased.

In this state, if any superconducting magnet 5 causes superconducting breakdown, the short circuit switch 12
The circuit is closed, and the circuit breaker 3 operates to open the circuit. Note that the operating timing of the short circuit switch 12 is the same as or earlier than the operating timing of the shield breaker 3. The electrical energy stored in the superconducting magnet 5 is transferred to the protective resistor 7 and the external protective resistor 11.
Heat is generated and consumed separately.

As a result, the protection resistor 7 mounted on the floating body 10 can be made smaller than the conventional device, and the same function as the conventional device can be obtained even without the diode 8.

In the above embodiment, the floating object of a magnetically levitated train has been described, but the present invention can also be applied to a case where a plurality of superconducting magnets are energized at the same time, such as an electromagnetic propulsion ship.

As described above, according to the present invention, an external protective resistor and a shorting switch are installed on the excitation power source side, and the shorting switch is operated in conjunction with the cutting operation, so that the This eliminates the need for a diode, allows the protective resistor to be made smaller, and has the effect of reducing weight.

[Brief explanation of the drawing]

FIG. 1 is an electric circuit diagram showing the configuration of a conventional superconducting device, and FIG. 2 is an electric circuit diagram showing the configuration of a superconducting device according to an embodiment of the present invention. In the figure, 1 is an excitation power supply device, 2 is a DC power supply, 3 is a wire cutter, 4 is a connecting terminal, 5 is a superconducting magnet, 6 is a persistent current switch, 7 is a protective resistor, 8 is a diode, and 10 is a floating device. 11 is an external protection resistor, and 12 is a short circuit switch. In addition,
In the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. A floating object side having a plurality of superconducting magnets each having a protective resistor, a DC power source for exciting the superconducting magnets in series, and an electrical connection between the DC power source and the superconducting magnets. A series body of an external protection resistor and a short-circuit switch is connected to the excitation power source side having a shield disconnector for separating and separating from the excitation power source side in a separable manner. A superconducting device characterized by being connected in parallel to. 2. The superconducting device according to claim 1, wherein the resistance value of the external protective resistor is smaller than the sum of the resistance values of the protective resistors of the plurality of superconducting magnets. 3. The superconducting device according to claim 1, wherein the operating timing of the short circuit switch is the same as or earlier than the operating timing of the shunt breaker.