SU978225A1 - Hard-gas arc-extinguishing device - Google Patents

Description

(54) MOTOR DIGITAL DEVICE

The invention relates to electrical engineering, namely to high-voltage fuses (switches) used to protect power transformers at 35220 kV at the highest voltage,

An autogas arc extinguishing device is known, which contains arc exchangers, a body tube made of solid Insulating gas generating material. A closed metal head is screwed onto it. There is a cavity in the tube in the form of two series-connected channels of large and small sections. Inside, there are installed switching elements: a contact device and the main insert, located at the ends of the tube and connected in series by means of a flexible current-carrying connection. Small currents are shut off in a narrow channel, while the action of a drive opens the contact systeg. To shut off large currents, there is a wide channel, where the quenching is carried out with a smooth insert C13.

It is also known a device containing in each tube one switching element in the form of a rosette contact. The operation of the device is analogous to the first one, but here there is a peculiar indicator of the magnitude of the current, an electromagnetic lock that locks the contact system in the narrow channel tube if a large short circuit current flows through the chamber. In this case, the contact system of the wide-channel part opens, more adapted to disconnecting currents of a large magnitude T2.

The disadvantages of both designs are complexity, a small switchable current, low reliability of operation.

Closest to the proposed

15 is a device comprising a metal end cap and an arc tube made of solid insulating gas generating hand material provided in the combustion zone.

20 arc cavity in the form of a series connection of a wide and narrow channels, spring-loaded inner and outer electrodes with a switching element, for example, melting

25 insert located in a narrow channel GZ.

The drawbacks of the known device are associated with low breaking capacity due to limited breaking capabilities of the wide channel tube and low reliability due to a large arc extinguishing time due to insufficient gas generation of the large channel tube. The purpose of the invention is to increase the breaking capacity and reliability of the structure. This goal was achieved in that additional gas-generating rods, made of solid insulating material, rigidly interconnected, for example, with metal rings and screws, were installed in the cavity of the wide tube channel. In this case, the switching element can be made in the tube of the wide channel, and the gas generating rods are made in the shape of a rectangle. FIG. 1 schematically shows an autogas extinguishing device, longitudinal section; in fig. 2 section aa in FIG. The device contains a tube made of a solid gas-generating insulating material, provided with a cavity in the form of successively connected single 1 wide and narrow 2 channels. The upper end of the tube is rigidly connected to the thread with a sealing metal head 3. The head is hermetically sealed with a stopper 4 fixed with a thread. In the internal cavity of the wide-channel tube 1, rods 5 are installed, also made of solid insulating gas-generating material. The rods are interconnected by rings b and fastened to them with screws 7 .. The electric part of the arc-suppressing device consists of a contact head 8 of a contact bolt 9 screwed on the thread into the plug 4. A flexible multi-wire copper link is pressed into the inner end of the bolt 9. 10, the opposite end of which is also pressed into the tip. 11 Atop the tip is screwed on the thread and sealed is a rigid conductive copper rod 12, which is the inner electrode of the chamber. The outer electrode is made in the form of a flexible copper multiwire connection 13 secured from the inside of the chamber by retaining fixed retaining screws 14. The outer end of the connection is terminated by an arrow shaped tip 15 equipped with a threaded hole. The inner 12 and outer 13 cores of the chamber are connected with the help of an element 1, 16 (for example, a fusible insert) and are spring-loaded retracted by a spring 17, which is rigidly connected to the stopper 4 and the stop plug 18. In the wide channel cavity of the chamber installed in it the rods 5 are made, for example, from organic glass (Fig. 2); The rods have a straight-line shape (this increases their gas-generating surface) and are set relative to each other with a gap, which allows the arc to penetrate to the entire surface of the rods. The rods are rigidly fixed to each other with the help of a flat metal ring 6 and screws 7 and are interconnected in such a way that a flexible connection cannot get into the gap between them. This makes it possible to avoid, when switching, the occurrence of a blocked channel, see our connection, which also contributes to the reliability of the arcing device. The device works as follows. t) a30M. When a short circuit occurs in the protected circuit, the current flowing through the arcing device increases sharply. The fault current melts the fuse box 16 and frees the rods 12 and 13 from each other. The rod 12 under the influence of the spring 17 begins to be drawn into the narrow channel part of the chamber. Under the action of a high electric field, the air gap between the electrodes, which was formed after the fuse-link fuse, breaks through and an electric arc occurs in it, reaching thousand and ten thousand degrees in narrow channels. This temperature affects the internal walls of the cavities of channels 1 and 2 and causes the material to evaporate, accompanied by intense gassing. The pelvis quickly fills the internal cavity of the enrichment chamber and begins to act on the rod 13 - a flexible connection, pushing it out. In gas generation, rods 5 play an important role, which are located, especially when large currents are switched off, in the very center of gas generation. The bend bond rolls along the ends of the rods facing the side of the GZ rod, which does not allow them to slip to their sides, which could cause an obstruction; channel. In this way, conditions are created for continuous gas blowing, which is the main condition for the operation of such quenching chambers. With the disconnection of currents of insignificant magnitude, a narrow-channel tube of quenching chamber plays a smooth role in extinguishing the arc. In this case, the main gas generation is provided in the narrow channel tube after tightening the arc there. A powerful longitudinal blast is formed along the narrow-band part of the chamber, which is sufficient for intensive cooling and deionization of the electric arc. At the same time, the volume of the felon 3 serves as a kind of receiver, in which gas is stored, which ensures the blowing of the arc channel and when the damage current passes through zero, when natural gas generation from the chamber walls is almost zero due to the absence of current in the arc channel and, hence, heat generation. The presence of a longitudinal blow at this moment produces the most intense deionization of the channel over the entire period of quenching.

When high currents are disconnected, the process of disconnection in time is several times faster and the tube of the small channel participates in extinguishing the arc, as a rule, only with its part adjacent to the tube of the wide channel.

After complete ejection of the flexible connection to the outside and the formation of the necessary air gap, the protected circuit is completely disconnected from the power source.

The introduction of gas-generating rods 5 allows for an increase in the gas-generating surface in wide channel 1, which, like bi-balancing, increases the volume of the wide-bore cavity with increasing diameter. This makes it possible to make samara significantly shorter by shortening the wide-canal part of the tube. In addition, the introduction of gas generating rods 5 allows reducing the arc quenching time due to an increase in pressure in the channel, as well as faster deionization and arc cooling. as a result of energy consumption for evaporation of gas-generating material.

The installation of rods with a gap allows the arc to uniformly affect the entire surface of the rods and the wide-bore cavity, which contributes to the growth of gas generation. Making a rod round reduces their total surface with the same mass. And making them rectangular increases the gas generation surface for the same mass of rods. The use of centering screws and fixing screws

obtaining the required rigidity of the structure and reduces the risk of turbulence in the flow of gases and vibrations that can destroy the design of the quench chamber.

 The cores of the rods may be made of another substance, with better gas generation than the tube material, for example, from organic glass. Therefore to mechanical strength

The rods are less demanding, which allows the use of less durable materials, but with better gas generation.

15

Claims (3)

1. Autogas arcing device containing a metal head and an arc tube, made of solid insulating gas generating material, provided in the arc burning zone with a cavity in the form of a series connection of a wide and narrow channels, spring-loaded internal and external electrodes with a switching element, for example, a fusible insert located in a narrow channel, characterized by In order to increase the breaking capacity and reliability of the design, additionally introduced solid insulation gas-generating rods rigidly interconnected with f are installed in a wide channel with metallic metal. and BINT. 2. A device according to claim 1, characterized in that the solid insulating gas generating rods are made in the shape of rectangles, Sources of information taken into consideration in the examination li USSR author's certificate., 355687, CL-. H 01 H 33/76, 1971. 2. USSR author's certificate 658616, cl. H 01 H 33/76, 1976., 3. USSR author's certificate 758293, cl. H 01 H 33/76, 1978.