JPH01122509A - Superconducting bus bar - Google Patents

Abstract

PURPOSE:To surely suppress the high-frequency surge and improve the insulation reliability by spirally winding a superconducting wire around a high-voltage conductor to form a coaxial and cylindrical superconducting bus bar. CONSTITUTION:A cylindrical metal pressure container 1 and a bus bar conductor 5 wound with a superconducting electric wire 3 on a cylindrical high-voltage conductor 4 are arranged to form coaxial cylinders. A liquid N2 2 is sealed between the container 1 and the bus bar conductor 5 to maintain the superconductive state of the superconducting wire 3. According to this constitution, when an overcurrent flows through the bus bar conductor 5 due to the high-frequency surge or the like generated at the time of the operation of a circuit breaker, the superconductive state collapses into the ordinary conductive state, and reactance is formed by the superconducting wire 3. The high-frequency component of the high-frequency surge can be removed by this phenomenon, and the insulation performance of the superconducting bus bar can be improved. The effect of this superconducting bus bar is large when it is put near the circuit breaker in particular.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a superconducting bus bar using a superconductor, and particularly to an insulating structure of a bus bar used for connecting normal conductive power transmission equipment.

(Conventional technology) The application of superconductors to power equipment has been studied for a relatively long time, and recently, along with the development of AC superconducting wires, research into applying superconductors to AC equipment such as transformers has also progressed. I'm here.

However, there are various technical problems in putting it into practical use.

This is because conventional devices using superconductors such as NbTi and NbSn, which are premised on cooling with liquid helium, require the extreme technology of freezing at extremely low temperatures.
One of the major factors was that economic efficiency and reliability were obstacles to practical application.

However, recently, the development of oxide-based high-temperature superconductors has progressed rapidly, and the discovery of materials such as YBaCuO, which exhibits superconducting properties such as zero electrical resistance and complete diamagnetic properties above liquid nitrogen temperature, has been reported in various places.

When such high-temperature superconductors are used, liquid nitrogen can be used as a refrigerant, which not only reduces the cost of the refrigerant itself, but also makes refrigeration technology much easier, making it not only economical but also highly reliable equipment. As a result, it is expected that in addition to superconducting generators, applications in power equipment such as superconducting transformers and superelectric power transmission lines will rapidly advance.

A superconducting substation may consist of a superconducting transformer, a superconducting circuit breaker, etc., which are connected by a bus made of ducts and high-voltage leads to supply energy to loads. In such superconducting equipment, it is necessary to install a current limiter to prevent the critical temperature from exceeding when the superconducting state is broken.

(Problems to be Solved by the Invention) In a gas-insulated bus bar that is insulated with SF6 gas, insulation performance against high-frequency surges that occur when opening and closing a disconnector is important. If a high frequency surge is applied while metal foreign matter is present in the gas insulated bus bar, there is a risk of dielectric breakdown. As a countermeasure against these problems, methods such as providing a resistor in a disconnector to suppress high frequency surges are known.

If such measures are taken, dielectric breakdown will be less likely to occur even if metallic foreign matter is present.

This problem is also important for superconducting buses.

In a superconducting bus, when a high-frequency surge occurs due to the opening and closing of a disconnector, an overcurrent flows through the bus conductor, and the bus conductor becomes normally conductive. However, even in the normal conduction state, the resistance value is low, so the effect of suppressing high frequency surges is quite small.

This invention was proposed to solve these problems, and its purpose is to reliably suppress high-frequency surges and obtain a superconducting bus without the risk of dielectric breakdown even if high-frequency surges occur. .

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, the present invention forms a superconducting wire made of a superconductor by winding it in a spiral shape around a high voltage conductor in a superconducting bus forming a coaxial cylinder. It is characterized by

(Function of the invention) In the superconducting bus of the present invention, when the superconductor formed by spirally winding the superconducting wire becomes normal conductive due to the influence of high frequency surge, reactance is formed and the high frequency surge is further suppressed. This is to ensure that it is suppressed.

(Example) Hereinafter, an example of the superconducting busbar of the present invention will be described in detail with reference to the drawings.

The figure is a diagram showing the configuration of a superconducting bus bar. In the figure, a pressure vessel 1 made of a cylindrical metal container and a bus conductor 5 in which a superconducting wire 3 made of a superconductor is wound around a similarly cylindrical high voltage conductor 4 are arranged to form a coaxial cylinder. . A cooling medium 2 such as liquid nitrogen is sealed between the pressure vessel 1 and the bus conductor 5 to maintain the superconducting state of the superconducting wire 3.

In this embodiment configured in this way, the bus conductor 5, which is made up of the superconducting wire 3 wound around the high voltage conductor 4, is in a superconducting state when an overcurrent flows due to a high frequency surge that occurs when opening/closing a disconnector. It collapses and becomes a normal conducting state, and the superconducting wire 3
reactance is formed by Due to this phenomenon, the high frequency component of the high frequency surge can be removed, and the insulation performance of the superconducting bus can be improved. The effect of this superconducting bus will be further improved if it is placed especially near the disconnector.

〔Effect of the invention〕

As described above, according to the present invention, by forming a bus conductor in which a superconducting wire is spirally wound around a high voltage conductor, even if a high frequency surge occurs, it acts as a reactance, so high frequency components are reduced. It is possible to provide a superconducting bus that can be removed and has excellent insulation performance and reliability.

[Brief explanation of the drawing]

The figure is a sectional view showing an embodiment of the structure of a superconducting bus according to the present invention. 1...Pressure vessel 2...Cooling medium 3...
Superconducting wire 4...High voltage conductor agent Patent attorney Noriyuki Chika Ken Yudo Ken Daishimaru

Claims (1)

[Claims] A pressure vessel made of a cylindrical metal container and a bus conductor in which a superconducting wire made of a superconductor is wound around a high voltage conductor also on the cylinder are arranged so as to form a coaxial cylinder, and the pressure vessel and the bus bar are arranged so as to form a coaxial cylinder. A superconducting bus consisting of a cooling medium sealed between conductors.