KR20000004827U - Instantaneous pressure reducing device for ground transformer - Google Patents

Abstract

The present invention relates to a net inlet pressure reducing device for a ground transformer, in particular, installed on top of the inner tank (20) of the transformer does not operate at the static pressure generated during normal use of the transformer, the energy of the momentary rapid rise such as internal short circuit of the transformer is generated When it is instantaneous burst at a certain operating pressure to reduce the pressure, at least one pressure outlet 26 formed on one side of the tank 20, and fixed along the edge of the pressure outlet 26 and the tank 20, a guide ring 44 inserted into the inside of the guide ring 44, a safety film 34 fixed to an upper end of the locking jaw 46 of the guide ring 44, and an upper portion of the safety film 34. It is characterized in that the fastening is fixed by the high information 38 is made of a breakdown hole 40 is formed to protrude to the bottom, the safety film 42 is expanded by a sudden pressure rise in the tank 20 The window is torn by the breaker 40 to allow the internal pressure of the tank 20 to be released to minimize the loss of human and material that may be caused by the explosion of the tank 20.

Description

Instantaneous pressure reducing device for ground transformer

The present invention relates to an instantaneous pressure reducing device used in a ground transformer, and more particularly, a pressure discharge port is installed at the top of a tank inside the ground transformer, and a guide ring, a safety barrier, and a destruction hole are installed there to surge. Instantaneous pressure reducing device that prevents the transformer from exploding and human and material loss around the transformer due to the sudden rise of the pressure in the transformer due to the breakdown of insulation inside the transformer due to abnormal voltage and the winding damage due to the overload. It relates to a ground transformer provided.

In general, the transformer converts the high voltage sent from the power plant into a suitable electric field for use at the consumer. These transformers are inflow type or dry type depending on the type of insulator, and most of the inflow transformers filled with insulating oil are used. . The structure of the inflow transformer consists of high-voltage winding, low-voltage winding, iron core, insulating oil, enclosure, etc.The high voltage is applied to the primary high-voltage winding, so that the primary and secondary pressures are applied to the secondary low-voltage winding by electromagnetic induction through the iron core. The contact pressure is caused by the turn ratio.

Recently, due to the complexity and density of the city, many ground transformers are installed on the roadside, so there is a high risk of unexpected accidents.In particular, abnormal voltages invade the primary side of the transformer due to lightning strikes and switching surges. Risk of injury to humans and property due to explosion of the transformer due to rapid internal pressure increase due to insulation breakdown inside the transformer due to overload and short circuit on the secondary side It was.

On the other hand, a small automatic pressure relief valve of a spring control type is installed and used in the above ground transformer, but it is possible to release a small and gentle pressure gradually rising during operation of the transformer due to its use and function, that is, internal pressure and Only the pressure control function between the atmosphere could be performed, and even in the case of large transformers, the spring control method and the bakelite plate rupture method were used only as a preventive measure to cut off the power by regulating the pressure for a long time or operating the relay. In spite of many efforts in the design and manufacture of the transformer due to the rapid pressure rise of the transformer by supplying the abnormal power supply as described above, the explosion and fire of the transformer due to the insulation breakdown inside the transformer are scattered. As a result, human and material loss may occur.

The instantaneous pressure reducing device for ground transformers of the present invention devised to solve the above-mentioned problems is that the instantaneous pressure reducing device of a suitable size is installed on the inner tank top of the transformer so that it does not operate at the static pressure generated when it is used normally. When an asynchronous transient voltage rises rapidly, such as an internal short circuit, it bursts at a certain operating pressure to reduce the pressure, thereby preventing tank rupture, scattering of high temperature insulating oil and gas, and fire. The aim is to minimize material loss.

The instantaneous pressure reducing device of the present invention for achieving the above object is a high-pressure and low-voltage winding is installed at the lower end of the tank filled with insulating oil to receive the high voltage of the power plant to convert to a suitable voltage for use by consumers In the above ground transformer, at least one pressure discharge port formed on one side of the tank top, a guide ring fixed along the edge of the pressure discharge port and inserted into the tank at a predetermined depth, and a safety film fixed to the upper edge of the guide ring. And, it is installed in the upper space of the safety film is characterized in that it is installed by a fixing bolt made of a breakdown port to be ruptured at the same time as the safety film is in contact with the expansion of the safety film, and a predetermined free space portion is formed outside the pressure discharge port Eject protection cover with multiple holes drilled on the top surface Characterized in that is installed.

1 is a partial cross-sectional view of the ground transformer is installed with a net pressure reducing device according to the present invention,

Figure 2 is an enlarged cross-sectional view of a part of the instantaneous pressure reducing device according to the present invention,

3 is an exploded perspective view of an instantaneous pressure reducing device according to the present invention;

Figure 4 is a perspective view of the destruction port of the first embodiment according to the present invention,

5 and 6 are a perspective view and a mounting cross-sectional view of the safety film of another embodiment according to the present invention.

※ Explanation of symbols for main parts of drawing

10: body 20: tank

22: insulating oil 24: tank cover

25: air layer 26: pressure outlet

28: high voltage incoming terminal 30: spray protection cover

31: hole 32: upper surface

33, 33 ': space part 34, 34', 34 ": flange

35: tightening hole 36: tightening nut

37: washer 38: fixing bolt

40: destroyer 41: blade

42: safety film 43: recess

44: guide ring 45: flat portion

46: Jam Jaw 47: Packing

48: protrusion 49: break

50: incision groove 60: high pressure / low pressure winding

70: low pressure draw terminal 80: automatic pressure discharge valve

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

1 and 2 are a partial exploded cross-sectional view of the ground transformer with an instantaneous pressure reducing device according to the present invention and an enlarged cross-sectional view of the instantaneous pressure reducing device.

The structure of the transformer according to the present invention is an insulating oil 22 filled to a predetermined upper portion of the tank 20 in the main body 10, and an air layer filled with air in the space between the upper end of the insulating oil 22 and the tank cover 24 ( 25 is formed, the high-pressure / low-voltage winding portion for converting into a voltage usable by the high-voltage power supply from the outside through the high-pressure inlet terminal 28 at the lower end of the tank 20 filled with the insulating oil 22 ( 60 is provided, the low pressure draw terminal 70 is provided with the voltage passing through the high-pressure / low-voltage winding unit 60 to the upper end of one side of the tank 20 to the outside, one side of the air layer 25 The automatic pressure discharge valve 80 is provided, which is the same as or similar to the structure of a conventional ground transformer.

On the other hand, the instantaneous pressure reducing device is a feature of the present invention, as shown in Figure 3, one or more pressure outlets (26) formed on one side of the upper surface of the tank cover 24, it is caught to be fitted to the pressure outlet (26) A jaw 46 is formed and the anodized coating guide ring 44 and the safety film 42 and the destruction hole 40 installed on the safety film 42, the safety film 42 and the guide ring 44 And a packing 47 fitted between the breakout holes 40. In addition, a predetermined space portion 33 is formed on the destruction hole 40 while surrounding the devices, and a plurality of holes 31 are formed on the upper surface 32 and the ejection protection cover 30 has an open rear surface. .

The safety film 42 is made of aluminum and fixed by flange 34 ″ on the upper surface of the packing 47 on the locking projection 46 of the guide ring 44 installed on the edge of the pressure outlet 26. The lower surface of the concave portion 43 of the central portion is located inside the guide ring 44 and is preferably installed in parallel with the upper surface of the tank cover 24 outside the guide ring 44. Destructor 40 is installed in the upper portion of the concave portion 43 of the inlet, the appropriate shape of the destructor 40 is an inverted triangle protruding deeper than the rim of both sides as the center portion as in the embodiment of the present invention It is desirable to form a cross-shaped blade 41 of the shape.

In addition, the guide ring 44 is damaged by contact with the demolition hole 40 by applying pressure to the safety layer 42 due to the swelling of the insulating oil 22 inside the tank 20 when the transformer is transported and installed. In order to prevent deformation, a protrusion 48 having a predetermined depth is formed inside the tank 20, between the tank cover 24 and the guide ring 44, and between the safety film 34 and the breaking hole 40. The packing 47 is provided to maintain the airtight inside the tank 20 to prevent moisture or moisture from penetrating into the tank 20.

On the other hand, Figure 4 shows an embodiment of the destruction sphere 40 according to the present invention, the flange 34 'is formed on the outer periphery and the blade 41 is formed in the central portion, which is the safety film The fastening hole 35 is perforated so as to be fixed to the installation above 42, and the blade 41 has a cross shape so that its height increases gradually toward the center, and the height thereof is formed in the center to the maximum, and the tank ( 20) the safety film 42, which is formed convexly into the guide ring 44 due to the instantaneous pressure increase generated inside, is convex toward the destruction hole 40, At the same time it is ruptured and the pressure inside the tank 20 is discharged to the outside.

In addition, the spray protection cover 30 has an upper surface such that the safety film 42 is ruptured due to an increase in the pressure inside the tank 20 so that the spray oil can not be directed to the front when the insulating oil 22 or the scattering of the insulating material is discharged and the gas is ejected. A plurality of holes 31 and the rear surface side at 32 are formed in an open form.

The instantaneous pressure reducing device of the present invention configured as described above is installed by inserting the fixing bolt 38 welded and fixed around the pressure outlet 26 on the upper surface of the tank cover 24 and then fixing it using the fastening nut 37. The spray protection cover 30 is installed to the outside of the device thus installed.

Hereinafter will be described the operation and effect of the pressure reducing device of the present invention made of the configuration as described above.

That is, an overload and a short circuit are generated by abnormal voltages supplied from the outside such as a lightning strike or an open / close surge, which destroys the insulation state in the transformer, causing instantaneous sparking due to decomposition of the insulation oil and high voltage, and thus the pressure of the tank 20 inside the transformer. Is rapidly raised and the insulating oil 22 and the gas are thermally expanded by the rapid pressure rise at this time and moved to the upper portion of the tank 20, and the air layer formed on the insulating oil 22 by the thermal expansion of the insulating oil 22 and the gas. (25) In addition, the pressure is transmitted to the cover 24 by compression expansion, whereby the inflated pressure is applied to the safety film 42 inside the cover 24 which is adjusted to an appropriate pressure.

Therefore, the safety film 42, which was initially convexly formed into the pressure discharge port 26, is convexly deformed toward the destruction port 40 and ruptures in contact with the sharp part of the destruction port 40, thereby causing the tank inside the transformer ( As the insulating oil 22 and the gas expanded at high temperature and high pressure in the tank 20 are discharged to the outside of the tank 20, the pressure in the tank 20 is reduced, and the high temperature and high pressure insulating oil discharged to the outside of the pressure outlet 26. (22) and the insulating debris, gas is discharged to the outside through the hole 31 while being once stopped by the blow protection cover 30 or discharged to the outside through the rear open portion of the blow protection cover 30 by the transformer Prevent explosion

Since the intrusion of abnormal voltage into the transformer is caused by lightning, switching surge, arc ground, etc., asynchronous transient voltage is supplied in a very short time and the pressure inside the tank 20 rises rapidly. The momentary pressure reduction of the present invention was difficult to cope with the conventional automatic pressure relief valve 80, since it proceeds very quickly at the speed of approximately 45 kPa from the time of occurrence to the explosion in the pressure of the tank 20 inside the transformer. It can be solved by the device, and in particular, it is possible to minimize damage to nearby people or objects due to the scattering of high-temperature insulating oil 22 and gas or the occurrence of fire due to the rupture of the transformer installed near the street. will be.

On the other hand, in addition to one embodiment of the safety film 42, as shown in Figures 5 and 6, the center portion is made of a flat portion 45 and may be used another embodiment in which the incision groove 50 is formed on the upper surface thereof. Bar, this is because the increased pressure from the inside of the tank 20 acts on the bottom surface of the safety film 42, the safety film 42 is expanded in the direction in which the cut groove 50 is formed, the cutting groove 50 is constant By breaking at a pressure or more so that the fracture portion 49 is formed, when applying this other embodiment, the configuration of the breaker 40 applied to the embodiment of the present invention does not have to be firmly provided. In addition, the destruction hole 40 is formed in the shape of a pin or other simple shape in addition to the blade formed in the body portion according to an embodiment of the present invention is installed on the top of the safety film 42 to effectively rupture of the safety film 42 Any shape can be said to belong to the scope of the present invention.

As described above, the instantaneous pressure reducing device of the present invention has a pressure discharge port having a diameter of a predetermined size formed on the upper end of the transformer inner tank, and a guide ring having a predetermined depth is inserted into the tank along the edge of the pressure discharge port. An aluminum safety film is provided on the upper part of the locking jaw of the guide ring, and a lower projection type break hole is provided at the upper part of the safety film. When the pressure rises rapidly inside the tank, the safety film is ruptured due to contact with the break hole. By discharging, it minimizes the loss of human and material that can be caused by the explosion of the tank, and also prevents the spread of bigger accidents by having the effect of preventing fire and breaking current through the temporary distribution of pressure. As well as having a simple structure is to have an effect that can be produced inexpensively.

Claims (4)

In the above ground transformer in which the high and low pressure windings are installed at the lower end of the tank filled with insulating oil and receive the high voltage of the power plant and convert the voltage into a proper voltage for use by the customer. At least one pressure outlet 26 formed at one side of the upper end of the tank 20, a guide ring 44 fixed along the edge of the pressure outlet 26 and inserted into the tank 20 to a predetermined depth, and the guide The tank consists of a safety film 42 fixed to the upper portion of the locking projection 46 of the ring 44, and a destruction hole 40 installed in the upper space portion 33 'of the safety film 42 and protruding downward. Instantaneous pressure reducing device for a ground transformer, characterized in that the cover 24 is fixed by the fixing bolt 38 provided on the upper surface. The method of claim 1, The breaker 40 is a momentary pressure reduction device for a ground transformer, characterized in that consisting of a blade 41 formed in the cross shape. The method of claim 1, The safety membrane 42 is a momentary pressure reduction device for a ground transformer, characterized in that the flange (34 ″) is formed on the edge portion and the concave portion (43) is formed on the inner surface. The method of claim 1, Above the pressure discharge port (26) is a momentary pressure reduction device for a ground transformer, characterized in that a plurality of holes (31) are drilled and one side of the blowout protection cover (30) is attached.