Longitudinal magnetic field electrode vacuum switch tube with low loop resistance

Abstract

The invention provides a vacuum interrupter with an axial magnetic field electrode with low circuit resistance, which has the low circuit resistance similar as a plate electrode and the strong breaking capacity similar as an axial magnetic field electrode and excellently resolves the conflict between the current conducting capacity and the short-circuit current breaking capacity. A conductive circuit related portion of the vacuum interrupter comprises a movable conducting rod, a contact base, an elastic contact support, an auxiliary current conducting block, a contact and a static conducting rod. The elastic contact support and the auxiliary current conducting block are disposed in an electrode formed by a movable contact, a static contact, a movable contact base and a static contact base, and the movable contact and the static contact are axially arranged correspondingly. The auxiliary current conducting block is cylindrical or circular, and is located inside or outside the elastic contact support. The elastic contact support and the auxiliary current conducting block match in shape, thereby forming an envelope structure. The elastic support is an elastic body axially disposed, and the thickness of the elastic support ranges from 1mm to 5mm. By applying the invention, the circuit resistance of the existing axial magnetic field vacuum interrupter with larger circuit resistance can be obviously reduced.

Description

technical field [0001] The invention relates to the technical field of vacuum switches. Specifically, it is a vacuum switch tube with longitudinal magnetic field electrodes supported by elastic contacts and auxiliary guide blocks. Background technique [0002] Before the present invention was proposed, those skilled in the art knew very well that a vacuum switch tube is also called a vacuum interrupter, which uses a pair of electrodes sealed in a vacuum, such as a contact or a contact and a magnetic field generating structure. Driven by the moving mechanism, it is an electric vacuum device that completes the connection and breaking of the circuit. In order to have a larger breaking current for the vacuum switch tube used in circuit breakers, simple flat electrodes, such as cake-shaped metal material contacts, can no longer meet the requirements. For this reason, there are flat transverse magnetic field electrodes successively, for example, they are processed on the contacts...

AI Technical Summary

Problems solved by technology

[0010] The cross-section of the conductor in the magnetic field generating part of the transverse magnetic field electrode is relatively large and the length is relatively short, so it has a relatively small loop resistance and can pass a large rated current. However, the melting and ablation of the contact surface cannot be avoided, so the breaking Capability is limited

At present, there is no vacuum switch tube with a transverse magnetic field electrode with a breaking capacity of 63kA and above; the longitudinal magnetic field electrode keeps the vacuum arc generated between the contacts in the non-aggregated state due to the longitudinal magnetic field, and the arc ablation is less than Transverse magnetic field electrode avoids the melting and ablation of the contact surface under the action of vacuum arc, and has a large breaking capacity. At present, almost all vacuum switch tubes with a breaking current of 63kA and above use longitudinal magnetic field electrodes, but due to the The shape of the conductor connected to the contact makes the current generate a circumferential component to generate a magnetic field. The conductive cross-section of this part of the conductor cannot be too large or / and the conductive length cannot be too short, so its loop resistance is also relatively large, which limits the size of its rated current The horseshoe core longitudinal magnetic field electrode has a small loop resistance similar to that of the flat electrode, but because the electrical pure iron used has a large magnetic hysteresis effect, when the breaking current is large, the hysteresis magnetic field affects the arc after the arc is extinguished. The deionization between the contacts causes breaking failure, so the breaking capacity of this structure is average

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