EA024057B1 - Device for adding oil to bushings of high-voltage apparatus and transformers - Google Patents

Abstract

The invention is related to power industry, in particular, to devices for adding transformer oil into input bushings of high-voltage apparatus and transformers without dismantling the bushings from equipment. The objective of the proposed invention is provision of a compact, lightweight, mobile device applicable to any power facility, for drying, degassing, nitrogenation of insulation oils, filling and refilling of transformers and electric equipment with this oil, drying and insulation of transformers under load, storage of sufficient quantity of degassed and nitrogenated oil eliminating the possibility of occurrence of a heat impulse that may initiate the beginning of uncontrolled chain process of oil oxidation due to inacceptable overheating of individual components of the device. The technical result is attained by provision of a device for adding oil to bushings of high-voltage apparatus and transformers comprising a housing with an electric pump, a degassing column with Raschig rings and a foam trap mounted therein, a thermometer, a peephole and a control valves system located on the housing, characterised in multiple increase of the number of Raschig rings in multiple increased degassing column, an oil line, a nitrogen line, a continuously controlled heaters, flow rate meters and an instrument for measurement of residual and positive pressure are mounted on the housing, and oil and water vapour catchers are mounted on the vacuum pump.

Description

The invention relates to energy, and in particular to devices for refueling the bushings of high-voltage devices and transformers with transformer oil without dismantling the bushings from the equipment.

There is a serious problem in the energy sector: loss of insulating properties by oils due to wetting (oils are very hygroscopic), and insulating oil is the main insulation in electrical devices (high-volume and low-volume high-voltage oil circuit breakers), power transformers, in high-voltage bushings, which are an integral part electrical apparatus and transformers. Moisturized oil transfers moisture to the paper insulation, which leads to the loss of paper insulation properties. Loss of insulating oils and paper insulation of their insulating properties leads to serious financial losses due to massive damage to electrical devices, power transformers and the cessation of electricity transmission to consumers.

Another problem: during operation, there are leaks of insulating oil, which lead to a decrease in the oil level below the permissible level, then it is necessary to top up the apparatus with dry, degassed or nitrided oil. Thus, during the operation periodically there is a need to restore the insulating properties of the oil and paper of the operating equipment or the need to prepare dry, degassed or nitrided oil to top up the equipment and prevent its damage.

Appropriate devices are needed to provide the insulating oil with the necessary insulating characteristics.

A known installation for degassing and filling oil - DZU - 30F, including an inlet filter, a degasser tank, a vacuum pump, an electric heater, a trap of oil and water vapor, a thermal relay, a system of pipelines and valves that ensure the operability of the device (NPO Electrum Russia Technical Description and operating instructions for the installation for degassing and filling oil DZU - 30F, St. Petersburg, 2002)

The disadvantage of this device is that the drying and degassing of oil is carried out in small portions of up to 30 l, this device does not allow nitriding of oil, the design of the device does not allow drying of significant volumes of oil, storing the stock of degassed or nitrided oil. The device does not allow drying insulation of transformers under load.

A known method of refueling the inputs of high-voltage devices, mainly transformers, and a device for its implementation. The design of the device is a syringe, under the piston of which an extremely small amount of degassed oil is collected. After connecting the device with the input via an oil pipe, due to the physical effect on the piston, the oil is pumped into the input under the influence of the piston, creating the necessary overpressure there (patent KI No. 2074433, application No. 94026541/07, 07/18/1994, publ. 02.27.1997 )

The main and significant drawback of this device is its narrow specialization only in refueling the bushings of high-voltage devices, mainly transformers. The specified device does not allow drying even small amounts of oil, as well as nitriding of oil. The design of the device does not provide for the possibility of storing a stock of degassed or nitrided oil.

A known installation of oil topping of inputs UVD-4, which includes an inlet filter, a gas degasser, a vacuum pump, an electric heater, a trap of oil and water vapor, a thermal relay, a system of valves and pipelines to ensure the operation of the installation. (Zavod Ukrbudmash JSC, Ukraine, letter of invitation from MEZET LLP dated September 11, 2006).

The disadvantages of this device include the fact that the amount of oil being prepared is produced in too small portions of up to 15 l, the inability to use this device to nitrate the oil, dry significant volumes of oil, the design of the device does not allow to store a stock of degassed or nitrided oil, and to dry the insulation of transformers under load .

A universal device is known, a unit for drying and degassing transformer oil, having a mass of 3.5 tons, is mounted in a 4900x2300x2500 mm van, which is mounted on a trailer with a lifting capacity of 7 tons to restore the insulating properties of oil, includes a booster pump, oil heater, and tanks for degassing oils, containers for nitriding oils, liquid meters, oil filters, exhaust pumps, vacuum pumps, vacuum gauges, process pipelines, a sufficient number of valves so that the circuit It is flexible, has significant dimensions, significant weight and cost, in addition, its use requires heavy trucks and truck cranes, which requires additional costs, the purpose of this device is the drying and degassing of large volumes of oil during installation and operation of individual powerful transformers of high 220 and extra high voltage 500, 750 kV at the installation site when additional transport costs are economically justified (Oil drying by zeolites and degassing. L.O. Manevich, p. 157, M., Energy, 1980).

- 1 024057

The closest is a device for filling hermetic bushings 110-750 kV with oil, including a housing with a viewing window, in which a gear pump with an electric motor and an oil heater are mounted, a degassing column with Rashig rings, an oil trap, a pipe and a valve for connecting a vacuum pump is mounted on top of the housing, the pump discharge through a system of pipes and valves is connected to a degassing column, an internal cavity of the housing, and an oil supply pipe to the input (Cancer V.P., Melyukhov V.A., article stroystvo to fill with oil tight bushings 110-750 kV, M., Energoatomisdat, Energy Journal, number 4, 1985, pp. 29-30).

The disadvantages of this device include the inability to use this device to nitrate oil, to dry significant volumes of oil, the design of the device does not allow to store a stock of degassed or nitrated oil, and to dry the insulation of transformers under load.

The objective of the invention is to create a compact, lightweight, mobile device with the possibility of its use at any energy facility for drying, degassing, nitriding, insulating oils, filling and refilling transformers and electrical equipment with this oil, drying the insulation of transformers under load, storing a sufficient amount of degassed or nitrided oil, eliminating the possibility of a heat pulse, initiating the beginning of a chain, uncontrolled process of oil oxidation, s and due to unacceptable overheating of individual elements of the device.

The technical result consists in creating a device that combines all the necessary functions: drying oil (removing moisture), oil degassing (removing air), nitriding oil (replacing air with nitrogen), adding oil to transformers and electrical devices with the possibility of creating the necessary excess in electric devices pressure, drying transformers under load, to restore the insulating properties of oil and paper insulation without putting the transformer out of operation in order to avoid interruption of electric transmission energy to consumers.

The technical result is achieved by the fact that the device for refueling the bushings of high-voltage devices and transformers, comprising a housing with an electric pump mounted in it, a degassing column with Raschig rings, a foam trap, a thermometer located on the housing, an inspection window, and a system of control valves, is characterized in that the number of Raschig rings in the multiple of the degassing column is increased by a multiple, the oil pipe, nitrogen pipe, continuously adjustable heater, flow meters, a device for and measurements of residual and overpressure, a trap of oil and water vapor is installed on the vacuum pump,

The figure shows a diagram of a device for refueling the inputs of high-voltage devices and transformers.

A device for refueling the inputs of high-voltage apparatuses and transformers contains a degassing column 1 formed by vertical and horizontal containers, with an upper opening closed by a tight upper cover 2 and two side openings closed by a tight side covers 3 and 4, with Rashig rings 5 mounted in it representing hollow cylinders in which the diameter is equal to the height, a spreader 6 is installed above them, which is a perforated plate, and a foam trap 7, bottom The electric pump 8 is fixed on the pump 1, on the case of the degassing column 1 there is a viewing window 9, a hermetically sealed vacuum gauge (a device for measuring residual and excess pressure), a power input for the electric pump 10, a hermetically sealed vacuum gauge, (a device for measuring residual and excess pressure 11, flow meters 12, 13, thermometer 14, continuously adjustable heater 15, system of control valves 16, 17, 18, 19, 20, 21, oil pipelines 22, 23, 24, 25, 26.27, nitrogen pipelines 28,

29, a vacuum pump 30 with a trap of oil and water vapor 31 mounted on it, a vacuum wire 32 extending from it, without the use of a support frame and additional metal structures, which reduces weight and increases the mobility of the device.

A device for refueling the inputs of high-voltage devices and transformers works as follows.

Oil is fed into the device due to the vacuum created in the device by a vacuum pump

30, without the use of a booster pump, which supplies oil to the device, how the proposed device differs from known analogues, after heating in a continuously adjustable heater 15, in which the oil filter is mounted, the power of the heater 15 changes smoothly, starting from zero, preventing individual elements from overheating, thereby preventing the appearance of a heat pulse, which initiates the onset of a chain and uncontrolled process of oil oxidation, enters the spreader 6, through which the oil enters the Rashi rings and 5, it spreads over the thin film, with film thickness less than that of analogues that achieved fold increase compared to similar oil spreading area, due to the magnification of the total surface area of the Raschig rings. Under the influence of temperature and rarefaction in the device, the moisture in the oil in the dissolved state boils, turns into a vapor state and is removed from the film by a vacuum pump 30; after passing through the Rashig rings, the oil enters the lower part of the degassing column 1, from where the electric pump 8, through oil lines 22, 24, is pumped out of the device, the amount of oil supplied to the device must be equal to the amount of oil pumped out of the device, called the performance of the device is regulated by valves 16, 18, 20 according to the readings of the flow meters 12, 13. In the drying mode (removal of moisture from the oil), the performance of the device is calculated and adjusted so that at any degree of humidification the insulating properties of the oil were restored to normalized parameters for one pumping of oil through the device.

In the process of degassing (removal of air from the oil), the required amount of oil is pumped into the lower part of the degassing column 1, then the electric pump 8 transfers the oil through oil pipelines 22, 25 to the spreading device 6, through which the oil enters the Rashig rings 5, spreads through them with a thin film, the air in the oil in the dissolved state is removed from the oil film by a vacuum pump 30, after the Raschig rings, the oil enters the bottom of the degassing column 1, the process of pumping oil through the Raschig rings 5 is simultaneously removed air from the apparatus it is repeated until the oil normalized parameters of air content in the oil (according to gas content).

The nitriding of the oil is carried out immediately after the end of the degassing process, when the oil reaches the normalized parameters for the air content in the oil (gas content), for which, during the degassing process, a nitrogen tank is connected to the nitrogen pipe 29, the vacuum pump 30 is turned off, the electric pump 8 remains in operation, pumping the oil inside the degassing column through Rashig rings 5, the valve on the nitrogen cylinder opens, valve 19 opens, in the degassing column an overpressure of 5% higher than atmospheric is created, the process of pumping oil along the Rashig 5 rings with the simultaneous saturation of the oil with nitrogen in the device case is repeated until the oil reaches normalized parameters for the nitrogen content in the oil, the nitriding mode is adjusted according to the oil flow controlled by the flow meter 12, and does not change further.

Claims (1)

A device for refueling the inputs of high-voltage apparatuses and transformers, comprising a housing with an electric pump mounted in it, a degassing column with Raschig rings, a foam trap, a thermometer located on the body, an inspection window, a system of control valves, characterized in that the number of Raschig rings is increased by a factor of several an enlarged degassing column, an oil pipe, a nitrogen pipe, a continuously adjustable heater, flow meters, a device for measuring residual and excess pressure are mounted Nia, on the vacuum pump installed trap oil vapors and water.