EA002372B1 - Electromagnetic drive of vacuum switch - Google Patents

Abstract

1. An electromagnetic drive of a vacuum switch, comprising a plate magnetic circuit with an armature mounted in it by rods adapted to axial displacement and fixing in two extreme positions, permanent magnets positioned in the middle part of the magnetic circuit on both sides of the armature relative to its axis, switching-in and off coils coaxially positioned in the magnetic circuit on both sides from the permanent magnets along the armature axis, characterized in that it is provided with guides from m-metal coaxially positioned in the magnetic circuit at its terminal opposite areas to arrange in them the armature rods and for providing fixed positions for the armature, whilst the permanent magnets are oriented with their like poles to the armature. 2. An electromagnetic drive of a vacuum switch according to claim 1, characterized in that it further comprises an indicator of the switch position, mechanisms of manual switching-off and blocking switching-in of said electromagnetic switch.

Description

The invention relates to electrical engineering, in particular to electromagnetic drives of vacuum high-voltage switches.

Known electromagnetic drives consist of an electromagnet (solenoid) and a mechanical holding device. Such drives are of two types: mounted in the frame of a vacuum circuit breaker and a separate version connected to the frame of the circuit breaker [1].

The disadvantage of such drives, created on the principle of electromagnetic driving force, is their large mass and multi-link kinematic connection from the rod of the armature of the electromagnetic drive to the rods of the mechanisms for compressing the vacuum interrupter chambers (hereinafter referred to as the VDK).

The new generation of vacuum circuit breakers has a drive part with electromagnetic drives and holding devices with magnets mounted under each phase of the circuit breaker.

This type of electromagnetic drives developed in Ukraine and made as a whole with the phase of the pole of the switch should include vacuum circuit breakers produced by SP RZVA (Rivne), this is a vacuum circuit breaker type BBKE-10 (Ukrainian patent No. 25132A) and a vacuum circuit breaker type BB / TEL-10 (patent of the Russian Federation No. 2202631C).

Foreign analogues include vacuum circuit breakers with electromagnetic drives of the type VBT-10-20 / 1600 (developer VEI, and manufacturer GN1P1 Kontakt, Saratov, Russian Federation).

To obtain the expected result and for the largest number of essential features similar to the essential features of the proposed invention, the electromagnetic drive of the BB / TEL-10 vacuum circuit breaker of the Tavrida Electric enterprise, Sevastopol, was taken as a prototype.

The proposed prototype, like the invention, consists of a control coil (in the invention of an on and off coil), magnetically soft parts: an armature, a guide (in the invention there are two). In addition, in the proposed prototype, a ring with hard magnetic material (two permanent magnets in the invention) and a breaking spring, which is absent in the invention, are installed.

Significant disadvantages of the prototype include the fact that the holding force of the magnetic latch (the force created by the magnetic field of the magnetized control coil of the magnetically solid ring of the electromagnetic drive) is relatively small, therefore the electromagnetic drive built on this principle is very sensitive to conditions of increased vibration and shock, which may be the cause of spontaneous tripping of the circuit breaker.

A disadvantage of the analogue is the fact that the design limits the use of mechanical locking of the drive, the functional value of which is to prevent the circuit breaker from being switched on in an intermediate (between the operating and control) position within the switchgear cabinet.

The above disadvantages of the prototype reduce its operational reliability (from the point of view of the degree of protection of staff), and, accordingly, limit the scope of such switches.

The present invention is a new type of electromagnetic drive in which the disadvantages of the analogue are completely absent.

The basis of the invention is the task of creating this type of electromagnetic drive using new design and technological solutions that can eliminate the disadvantages of the prototype. At the same time, technical and economic indicators and weight and overall parameters should be improved and the highest degree of reliability in operation should be achieved.

The basis of the invention, namely the electromagnetic drive of a vacuum circuit breaker, is based on the principle of a two-position magnetic system of an electromagnetic drive. The armature of the electromagnetic drive in two extreme positions (on and off) is held by the magnetic field of two permanent magnets. Turning on or off will only begin when the holding forces of the permanent magnets are canceled by the excitation of one of the coils of the electromagnetic drive.

Therefore, the task is achieved by using a multifunctional electromagnetic drive, in which, with the help of on and off coils, the drive armature moves from one extreme position to the opposite, with permanent magnets of a two-position electromagnetic drive made of rare-earth metals-iron-boron (REM-ReV) compounds or intermetallic compounds of cobalt with rare-earth metals, form two magnetic circuits, the so-called magnetic latches, in which anchored. In this case, the permanent magnets are installed with the orientation of the poles of the same name in the direction of the armature located between these permanent magnets, coaxially with the on and off coils and with a gap relative to the magnetic circuit in one of the coils depending on the position of the armature. In addition, the electromagnetic drive is made of soft magnetic material: anchor, guides and magnetic circuit, made of burdened

W-shaped plates interconnected by upper and lower support plates.

The task is also achieved by applying a switch position indicator in the electromagnetic drive, as well as switching on locking mechanisms that are not available for the prototype, and manual disconnection, implemented through the switch shaft of the prototype.

The use in the electromagnetic drive of the present invention allows for the fixation of the armature not only in the on position of the switch, as in the prototype, but also in the disconnected by means of two magnetic latches.

The present invention allows for the creation of a high-tech, unified series of electromagnetic drives with different capacities required to create a new series of vacuum circuit breakers.

In addition, the application of the invention allows for mechanical locking of the drive.

Therefore, according to the authors, such constructive solutions have an advantage over existing electromagnetic drives of vacuum and other circuit breakers.

In FIG. 1 shows the placement of an electromagnetic drive in the frame of a vacuum circuit breaker;

in FIG. 2 - electromagnetic drive of a vacuum circuit breaker (top view);

in FIG. 3 - electromagnetic drive of the vacuum circuit breaker (side view).

In the frame of the vacuum circuit breaker, the electromagnetic drive 1 is structurally placed (see Fig. 1), kinematically connected to the shaft of the circuit breaker 2. On the frame there is a pole of the vacuum circuit breaker, consisting of an insulating rod 3 with compression springs 4, flexible conductive connection 5, lower contact 6, poured into the insulating casing 7 of the airborne complex 8 and the upper contact 9.

Structurally, the electromagnetic drive of the vacuum circuit breaker (see top view of Fig. 2) consists of the following components and parts: plates of the magnetic circuit 10, anchor 11, two permanent magnets 12, an actuator rod 13, bearings 14, lock washers 15, an axis 16, a guide block 17, the locking plates of the guide block 18, the fingers 19, the on-coil 20 and the trip coil 21, as well as the off-guide guide block 22, the rollers 23, the spring 24, the shaft of the manual shut-off mechanism 25 and the trip rod 26.

The upper 27 and lower 28 base plates (see side view of Fig. 3) hold the lined magnetic circuit. In addition, the drive includes a manual shut-off mechanism 29, a locking mechanism for closing the switch 30 with a stem 31 and a spring 32. The holding pin 33 makes it possible to support the intermediate shaft 34 with levers. The position indicator of the switch 35 indicates the position of the switch and the drive, which also includes support plates 36 and 37 and guides 38 and 39.

The operation of the electromagnetic drive is as follows. The strength of the magnetic field created by the electromagnetic drive, due to its magnetic characteristics, moves the movable armature 11 (Fig. 2) from one position to the opposite and at the same time directly through the levers of the intermediate shaft 34 (Fig. 3), the shaft of the switch 2 (Fig. 1) and insulating rods 3 (Fig. 1) acts on the movable contacts of the VDK 8 (Fig. 1). Such a kinematic scheme ensures minimal wear of its elements throughout the life of the vacuum circuit breaker.

Permanent magnets 12 (Fig. 2) of the electromagnetic drive of the vacuum circuit breaker 1 (Fig. 1) hold the contacts of the VDK 8 (Fig. 1) in extreme positions on and off due to the aforementioned magnetic latch system, which is based on the closure of the magnetic on or off magnetic circuit accordingly, the anchor 11 (Fig. 2).

To turn on the switch, it is necessary to pass a direct current through the inclusion coil 20 (Fig. 2) at which the force in the magnetic circuit of the inclusion, despite the large gap between the armature and the magnetic circuit (see Fig. 2), exceeds the value of the attractive force of the armature in the magnetic circuit shutdowns where there is no similar gap.

Upon reaching the amount of pulling, the armature 11 (Fig. 2) of the electromagnetic drive 1 (Fig. 1) begins to move with acceleration, setting in motion the entire kinematic circuit of the switch. In this case, the insulating traction of the poles 3 (Fig. 1), moving up, close the contacts of the VDK 8 (Fig. 1). Anchor 11 (Fig. 2) stops its movement by selecting the aforementioned gap, and is fixed in this position by a magnetic latch.

The smaller the gap between the armature 11 (Fig. 2) and the magnetic circuit 10 (Fig. 2) of the magnetic circuit, the greater the attractive force of the permanent magnets 12 (Fig. 2).

The resulting holding force is approximately 800 N. The switch is reliably fixed in the on position even under shock and vibration (which is a drawback of the electromagnetic drive of the vacuum circuit breaker, taken as a prototype).

Therefore, the inclusion of the switch is the result of the combined action of the magnetomotive force of the switching coil 20 (Fig. 2) with current and the action of permanent magnets 12 (Fig. 2), which have a high energy intensity.

To open the circuit breaker, it is necessary to pass a current through the trip coil 21 (Fig. 2) in a direction in which the force acting on the armature 11 (Fig. 2) exceeds the resulting holding force of the magnetic latch. This force is the difference between the forces of attraction of the permanent magnets 12 (Fig. 2), atmospheric pressure on the airborne hoses 8 (Fig. 1) of three poles and the force of three groups of compression springs 4 (Fig. 1) of the switch poles.

At the same time, moving, the armature 11 (Fig. 2) of the electromagnetic drive closes the magnetic circuit to disconnect the drive and thereby clearly fixes the circuit breaker in the off position with a magnetic latch provided by the permanent magnets 12 (Fig. 2) of the vacuum circuit breaker. Accordingly, the operation is completed by moving the position indicator 35 (Fig. 3) located on the on-rod 13 (Fig. 2), and the inscription OFF appears in the window of the front wall of the switch. An essential feature of the design of the electromagnetic drive is that the locking mechanism of the switch 30 (Fig. 3) allows it to act on the stem 31 (for example, by a special mechanism of the withdrawable element) through the corresponding hole in the switch frame and move it in the guide holes of the electromagnetic drive and thereby block anchor 11 (Fig. 2), which, accordingly, makes it impossible to turn on the switch (for example, while moving the switch in the switchgear cabinet).

Such an electromagnetic drive was created at the RZVA joint venture (Rivne) and passed all standard (electromechanical, switching, etc.) tests with the newly created vacuum circuit breaker.

According to the authors, such an electromagnetic drive of a vacuum circuit breaker is necessary for operating organizations of the national economy’s energy networks.

Information sources

1. Afanasyev V.V., Yakunin E.N. Drives for circuit breakers and high voltage disconnectors. L. Energoatomizdat. Leningrad branch. 1982 g.

Claims (2)

CLAIM 1. Electromagnetic actuator of the vacuum circuit breaker, which contains a plate magnetic core with an anchor mounted on rods in it with the possibility of axial movement and fixation in two fixed extreme positions, permanent magnets mounted in the middle part of the magnetic circuit on both sides of the armature relative to the axis of the latter, the on-coil shutdowns, coaxially mounted in the magnetic core on both sides of the permanent magnets along the axis of the armature, characterized in that it is provided with guides of magnetic material, with ososno installed in the magnetic core at its end opposite sites to accommodate the armature rods and provide for the anchor fixed positions, while the permanent magnets are oriented poles of the same name in the direction of the anchor. 2. The drive of the vacuum switch according to claim 1, characterized in that it additionally contains the position indicator of the switch, the mechanisms for manual shutdown and blocking the switch on switch.