EA030334B1 - System and method for realizing kerosene gas phase drying to transformers assembled on-site - Google Patents

Abstract

A system and method for realizing kerosene gas phase drying to transformers assembled on-site. A transformer tank (11) for holding a transformer serves as a working container for gas phase drying process. The transformer tank is connected to gas phase drying equipments outside by connecting pipes. The gas phase drying equipments are assembled into a module. The system is simpler, while it reduces fabricating and installing cost for a transformer gas phase drying process system.

Description

The invention relates to the production and manufacture of transformers and, more specifically, to a system and method, which carry out the process of gas-phase drying of the transformer case by the method of gas-phase drying with kerosene at the site of the transformer.

The level of technology

In recent years, the electric power industry has been developing in China, especially hydropower (clean energy). However, industries that need electric power development in China are mainly located in the southwestern, northwestern and other remote areas (over 80%), thereby being very uncomfortable for transporting bulky goods. In addition, due to the considerable size of a transformer, especially a large transformer weighing hundreds of tons, it is impossible to transport it to the construction site entirely due to many factors, such as the limited width of the road, the height of the tunnel, the permissible bridge load, etc. Therefore, the transformer is usually dismantled for transportation and re-assembled on the spot after delivery. However, since the transportation of the disassembled transformer and its assembly at the installation site takes a long time, the insulation details of the transformer may be exposed to moisture. Therefore, how to carry out the process of drying the transformer at the installation site becomes a key issue that should be resolved.

At present, the following traditional methods are usually adopted for drying the transformer at the installation site, for example, vacuum drying with hot air, spray vacuum drying, drying by thermal action of current (including the method of heating by eddy currents in the oil tank, the method of heating by zero-sequence currents, the method of heating short circuit current) and so on. However, all of the above drying methods have disadvantages such as low heating temperature, long heating time, uneven heating and incomplete drying.

For a large-capacity transformer and a high voltage level, the best drying method is gas-phase drying, which has the advantage of high drying temperature, high drying speed, short drying time, uniform heating, full drying, and is able to clean a variety of transformers, because it uses kerosene vapor as a coolant, and the entire drying process is carried out entirely at low oxygen content.

The gas-phase drying system using the above gas-phase drying method is a rather large and complex system. Generally speaking, in addition to the layout of the vacuum chamber and the huge cooling system, it is necessary to use a sufficient amount of water and a heat source, as well as to carry out large-scale construction work, for example, a coarse filter should be built under a heated brick layer to ensure the height difference between the drying chamber and coarse filter. Currently, all manufacturers of transformers produce a stationary gas-phase drying system, that is, they build it on a stationary foundation for drying a transformer at a transformer manufacturing plant. Basically, a stationary vacuum chamber in said stationary gas-phase drying system is the main process container. In the drying process, the dried objects are placed in a vacuum chamber, and then the process of heating, evacuating, and so on is carried out in a vacuum chamber. Other components of the gas-phase drying system, such as an evaporator, are also placed around the vacuum chamber. To maintain the temperature in the vacuum chamber, the outer wall of the vacuum chamber is equipped with a steam tubular heater for heating and an insulating material for heat preservation, as well as outer armor, and the lid (door) of the chamber has a special hydraulic system to maintain its airtightness. In the case of a horizontal vacuum chamber, there is a platform trolley inside to accommodate the transformer housing. Outside the vacuum chamber there is a traction device for introducing the transformer into the chamber and removing it from it.

Turning now to FIG. 1, which illustrates the process flow diagram of a gas-phase drying system with an external evaporator (i.e., a stationary gas-phase drying system) known in the art. It represents the principle of operation of a known gas-phase drying system with an external evaporator. A single arrow, as shown in the drawing, shows the direction of the kerosene vapor, a double arrow shows the vapor return path, a triple arrow shows the kerosene return path; in the diagram, 1 - vacuum device, 2 - water cooling system, 3 - door device of the vacuum chamber, 4 vacuum chamber, 5 - condensate collection system, 6 - wastewater receiving device, 7 evaporator, 8 - waste oil tank, 9 - oil storage tank, 10 - steam supply system.

The technological scheme of the stationary gas-phase drying process includes the following operations:

Operation 1: after lifting the transformer case onto the platform trolley, the platform trolley is pulled into the vacuum chamber with the help of a traction device.

Step 2: insert the temperature sensor into the transformer case, then close the door of the vacuum chamber and press the door of the vacuum chamber tightly with a clamping device on the door of the chamber.

Operation 3: begin the process of gas-phase drying. The process of gas-phase drying is divided into

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five stages:

The preparatory stage: first, the pressure inside the vacuum chamber 4 is reduced using a vacuum device 1, while the evaporator 7 begins to heat the kerosene with steam supplied from the steam supply system 10.

Heating stage: the evaporator 7 continues to heat the kerosene with steam supplied from the steam supply system 10, so that the liquid kerosene turns into kerosene vapor, and the kerosene vapor is sent to the vacuum chamber 4 through the pipeline, thereby heating the transformer housing inside the vacuum chamber and the transformer housing gradually heats up, and in the course of the heating time, the moisture in the insulating material on the transformer case evaporates, forming in the vacuum chamber a sort of gas mixture consisting of kerosene vapor, water vapor and air Ear leaked into the vacuum chamber. The gas mixture is directed through the return pipeline to condenser 5. In condenser 5, water vapor and kerosene vapor are condensed by the action of water cooling system 2, while the leaked air is vented to the atmosphere using a vacuum pump (not shown in Fig. 1). Due to the difference in specific gravities, condensed water and kerosene are separated in a condenser, then the separated kerosene is pumped out with an oil pump (not shown in Fig. 1) to the evaporator 7 for recirculation, the separated water is brought to the device 6 for receiving wastewater.

The pressure reduction stage: when most of the moisture in the transformer insulation material has been removed, the heating of kerosene and the supply of kerosene vapor are stopped, and the gas mixture is brought into the vacuum chamber 4 using a vacuum device 1 so that the residual kerosene in the insulation material is re-evaporated.

The high vacuum stage: finally, the vacuum chamber 4 is further evacuated using a vacuum device 1 so that residual kerosene and water deep in the insulating material are further evaporated until the drying is completed.

Vacuum discharge stage, i.e. air intake stage: fill the chamber with air to discharge the vacuum inside after the condition of completion of the drying process is met, and ultimately remove the product from the chamber.

From the layout of the system and the process with the above-mentioned stationary gas-phase drying, it can be seen that the production of the specified gas-phase process technology is very expensive, while it is very uneconomical. In addition, the system is limited in many aspects with regard to its environment, that is, it is necessary to use a stationary vacuum chamber (container for transformer placement), which is very expensive and requires a sufficient amount of water and a heat source, as well as a large amount of construction work, for example a vacuum chamber requires a foundation; a coarse filter must be built in a pit lower than a vacuum chamber, and so on. The process of gas-phase drying of the transformer can be performed only when the above is done. Therefore, it is impossible to install this type of gas drying equipment at the place of installation of the transformer.

Summary of Invention

To solve the problem of design complexity, high cost and infrastructure limitations of the known stationary gas-phase drying system, the present invention proposes a system and method by which a transformer can be assembled at the installation site of a transformer with a gas-phase drying process that can provide gas-phase transformer drying at the installation site transformer without any infrastructure limitations, thereby eliminating the shortcomings and flaws of the prior art.

To solve the above problem, the present invention replaces a vacuum chamber in a stationary gas-phase drying system with an oil tank of a transformer that houses a transformer, and makes gas-drying equipment as a module, and then assembles and connects the corresponding system components after the transformer has been delivered to the place of installation of the transformer, thereby realizing the process of gas-phase drying of the transformer at the place of installation of the transformer.

The technical solution adopted for solving the technical problem according to the present invention is a system in which gas-phase drying of transformer kerosene assembled at the installation site is used, containing a process container, which may contain a transformer, and gas-drying equipment placed outside the process container . The system uses an oil tank of the transformer, which contains a transformer, as a process container for the gas-phase drying process, and the oil tank of the transformer is connected by connecting pipes with external equipment for gas-phase drying.

The oil tank of the transformer according to the present invention is additionally equipped with a gas passage channel, an oil passage channel and a temperature signal inlet for connection with external gas-phase drying equipment.

In this case, the gas passage channel includes an inlet channel for kerosene vapor and a vacuum opening, and the inlet channel for kerosene vapor is placed in the middle of the lower part of the lateral surface.

The transformer’s oil tank and vacuum port are placed on top of the transformer’s oil tank.

A guide nipple is preferably placed in the inlet channel for kerosene vapor, and a support partition is installed on the guide pipe to discharge kerosene vapor flowing into the guide pipe to thereby protect the insulation of the transformer case from local overheating at the kerosene vapor inlet.

In addition, an inlet for dry air is installed on a vacuum line connected to a vacuum orifice, and an inlet for dry air is connected to a dry air generator.

The oil passage according to the present invention includes a first exhaust kerosene channel and a second exhaust kerosene channel, the first exhaust kerosene channel, which is placed in the side wall at a certain height from the bottom of the transformer’s oil tank, as the main oil outlet channel of the transformer gas-phase drying, while the second exhaust kerosene channel is placed at the bottom of the oil tank of the transformer to drain all the oil from the oil tank transf ormator. Outside, the first exhaust kerosene channel and the second exhaust kerosene channel are connected to a kerosene return module.

The temperature signal inlet is preferably located in the middle of the lower part of the transformer oil tank. Through temperature signal inlet in the oil tank of the transformer can be mounted several temperature sensors. Several temperature sensors are inserted respectively into different parts of the transformer housing. Equipment for gas-phase drying includes a control device for automatic control of the system. The control unit is connected to the corresponding temperature sensors by output lines, which transmit a signal of the detected temperature to the control unit.

The gas phase drying equipment of the present invention is assembled as a module. The specified equipment for gas-phase drying can be made in the form of an assembly module of equipment for gas-phase drying.

In addition, the gas-phase drying equipment according to the present invention is made up of a plurality of modules including a vacuum condensation module, a kerosene vapor heating module, a kerosene return module, and a cooling module, the cooling module being connected to the kerosene vapor module respectively, and the heating module kerosene vapor is connected respectively to the kerosene return module and the vacuum condensation module, the oil tank of the transformer is connected respectively to the module va kum condensation, kerosene vapor heating module and kerosene return module.

Preferably, the gas-phase drying equipment further includes an oil storage tank and a waste oil tank, which are also made in the form of modules. The oil storage tank is connected respectively to the vacuum condensation module and the kerosene vapor heating module, while the waste oil tank is connected to the kerosene vapor heating module.

The above modules are placed in a free order according to the topographic features of the terrain on the production site by combining the modules and connecting pipelines are laid between them. Using the modules according to the present invention, it is possible to simplify the compilation of a gas phase drying process system and facilitate the quick assembly of the respective parts of the system, thereby solving the problem of carrying out the gas phase drying process at the installation site of the transformer.

Preferably, the vacuum condensation module, the kerosene vapor heating module, the kerosene return module and the cooling module are all implemented in the container structure. Since the external packaging means of the modules according to the present invention are adapted to the design of the container, the installation of the system becomes easy and simple.

In addition, the vacuum condensation module mainly includes an assembly of a vacuum unit, a condenser and a collection tank, with the condenser inlet channel connected to a vacuum hole on the transformer oil tank, and its exhaust channel is respectively connected to the vacuum unit assembly and the collection tank.

The kerosene vapor heating module mainly includes an evaporator and an oil heat carrier heater, the oil coolant heater is used to heat the evaporator, the evaporator inlet channel is connected to the kerosene return module and its exhaust channel is connected to the kerosene vapor inlet channel of the transformer oil tank.

The kerosene return module mainly includes a coarse filter, and the coarse filter inlet is connected to the first kerosene outlet and the second kerosene outlet on the transformer, respectively, and its outlet is connected to an evaporator.

The cooling module mainly includes a water tank and a water cooling unit, and parts of the respective modules are interconnected by connecting pipes.

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By using an ordinary cooling module (i.e. it consists of large and small water cooling units, as well as a water tank) according to the present invention, it is possible to supply cooling water to devices in the vacuum condensation module and the kerosene vapor heating module, respectively, thereby solving the problem of water shortage in place installation of a transformer and refusing a rather cumbersome water cooling system in a stationary gas-phase drying system (since the enterprise for the production of transformers usually It does not have problems with water sources for the application of a traditional stationary gas-phase drying system, usually it is necessary to construct a water basin with a capacity of 100-300 m ³ outside the production hall with digging a pit of considerable depth and installing a cooling tower above the water basin for natural cooling of water). According to the present invention, water is almost not lost during the drying process, since in the present invention a cooling module is used, which leads to a simple construction and occupies a small area, thereby with a significant saving of water resources. However, the use of a traditional stationary gas-phase drying system must consume a huge amount of water to reduce the water temperature due to the high outdoor temperature in the summer, thereby leading to a waste of water resources.

The evaporator used in the present invention is preferably an external single evaporator for evaporating and distilling kerosene, and in the heat transfer oil heater uses electrical energy to heat the heat transfer oil, as a result of which the heat transfer oil heats the kerosene, thereby converting the liquid kerosene into kerosene vapor. By heating kerosene using an oil coolant, the system according to the present invention is not limited to the infrastructure at the installation site, that is, the system according to the present invention can realize a gas-phase drying process without the need to connect to a heat source as abundant as the traditional stationary gas-phase drying process.

In addition, the connecting pipes of the system according to the present invention are sliding pipes for regulating the connections so that the length of the connection can be increased according to the topological features of the terrain at the installation site.

For connecting pipes, it is preferable that, with the exception of the pipeline for connecting the cooling module, which is a plastic hose with steel wire reinforcement, all other connecting pipes are sliding stainless steel hoses.

The coarse filter includes a cavity in which a kerosene inlet pipe and a kerosene outlet pipe are provided, the filter grid is in the cavity, and in the cavity, in addition, there is a hole for the external vacuum that can be connected to the external vacuum system.

During the drying process of the transformer, the external vacuum system is connected through an external vacuum opening. Through the external vacuum opening, the external vacuum system can regulate to maintain a certain pressure difference between the transformer’s oil tank and the coarse filter cavity, thereby achieving the goal of accelerating kerosene circulation throughout the entire gas-phase equipment so that liquid kerosene can circulate quickly, even if there is no height difference between the drying chamber and the coarse filter, and thus there is no need to dig a pit in the ground to accommodate the coarse filter cleaning up.

The inlet kerosene tube is preferably located in the side wall of the cavity, being opposite the filtration grid, thereby reducing the height between the inlet kerosene tube and the filtration grid, resulting in a further reduction in the height difference between the transformer oil tank and the coarse filter and achieve rapid circulation of liquid kerosene. Therefore, on-site installation of the transformer, even if the pit is not dug, still can be provided with the circulation of liquid kerosene in the equipment for gas-phase drying.

In addition, a second kerosene inlet is placed on the side wall of the cavity. The specified second kerosene inlet pipe can be connected to the first exhaust kerosene channel on the oil tank of the transformer. The second kerosene inlet may be connected to a second kerosene outlet on the oil tank of the transformer. Moreover, the first exhaust kerosene channel has an enlarged diameter and thus can circulate kerosene, but kerosene at the bottom of the oil tank of the transformer cannot be completely withdrawn due to the location of the channel at a certain height relative to the bottom of the oil tank of the transformer; The second exhaust kerosene channel has a smaller diameter and thus cannot participate in the circulation of kerosene, but can remove kerosene from the very bottom of the oil tank of the transformer. The purpose of this design is to ensure that the problem of the circulation of kerosene during the drying process and the problem of extracting all the kerosene in the oil tank of the transformer after the drying process is complete can be resolved without changing the design of the oil tank of the transformer.

The cavity preferably extends backward to form a collection chamber capable of accommodating the condensed kerosene fluid. External vacuum hole is made in

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precast chamber. At the bottom of the camera assembly place the exhaust kerosene pipe. The bottom of the collecting chamber is additionally equipped with a pump for pumping kerosene. Condensed kerosene fluid after passing through a pump for pumping kerosene flows from the kerosene discharge pipe. A liquid level regulator can be placed in the collecting chamber to control the start or stop of the kerosene pump.

In the present invention, the transformer housing is dried at the place of installation of the transformer using the transformer oil tank as the drying container instead of the vacuum chamber. However, the working space in the oil tank of the transformer is limited, which will directly affect the circulation of liquid kerosene. By creating a collection chamber behind the cavity, condensed liquid kerosene can be collected and stored. When the amount of condensed kerosene reaches a certain level, the liquid level controller sends a signal to the kerosene pump, the kerosene pump sends the liquid kerosene to other items of gas-phase kerosene recirculation equipment, thereby solving the problem of frequent starting the kerosene pump in the well-known device, extends the service life of a kerosene pump, saves energy and provides kerosene recirculation during the heating process.

The filtration network is preferably placed in the middle of the cavity and opposite the inlet kerosene pipe. The filtration grid separates the cavity into the front section and the rear section. The rear section is a collection chamber, while the bottom of the front section is additionally equipped with a drain channel suitable for removing sediment of contaminants in the cavity to facilitate cleaning.

The filtration net preferably has the shape of a half cylinder with a bag. This design can make a more uniform flow of liquid kerosene flowing from the side wall of the cavity into the filtration network.

The cavity is preferably covered with a heat-saving layer that can retain the heat of liquid kerosene held in the cavity so that before the stored liquid kerosene enters the transformer oil tank for recycling, it is possible to reduce heat loss during heating of kerosene to save energy.

In addition, the cavity additionally has an air inlet with an air passage valve (i.e., a vacuum relief hole). An air passage valve is used to open or close the air inlet. The front end of the air intake has a knee. To clean the filtering mesh, open the air passage valve, release the vacuum inside the cavity through the air inlet. The front end of the air intake, being made in the form of a knee, can play the role of a fuse, preventing hot liquid kerosene from spilling out of the air inlet and injuring workers at the production site due to malfunctioning or equipment failure when the vacuum is removed to clean the filter mesh.

Moreover, a hole is made at the top of the cavity in the position corresponding to the filtration grid. The opening is closed with a lid that can be opened. The lid has a viewing window through which the operator can at any time see precipitation on the filtration grid.

Compared with the coarse filter according to the prototype, the above coarse filter has the following advantages: 1) does not require construction work, that is, digging a pit in the ground, thereby significantly reducing the cost of manufacturing a transformer; 2) thanks to the collecting chamber, it is not necessary to frequently start the pump for pumping kerosene, thereby protecting the coarse filter; 3) thanks to the knee at the front end of the air inlet, the operation to replace the filtering mesh becomes safer; 4) a heat-saving layer outside the cavity can reduce energy losses during the drying process, and ultimately the cost of manufacturing a transformer.

In addition, the transformer oil tank is equipped with a heat-saving device for keeping heat in the transformer oil tank. The heat saving device of the oil tank of the transformer according to the present invention is preferably placed on the heat saving layer outside the transformer, and an auxiliary heating device is placed at the bottom and on the side wall of the oil tank of the transformer.

In this case, the auxiliary heating device placed on the side wall of the oil tank of the transformer is a tape electrical heating element for heating, the auxiliary heating device placed at the bottom of the oil tank of the transformer is an infrared heating plate.

In addition, under the bottom of the oil tank of the transformer there is a bed, the upper surface of which is an inclined surface, with the inclined surface inclined along the length direction of the oil tank of the transformer so that the transformer oil tank placed on it is inclined. Due to the sloping bed, the oil tank of the transformer on it is inclined, thereby facilitating the uniform flow of oil in the oil tank of the transformer from the tank.

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The system additionally includes a control unit for fully automatic control of the entire system using a computer. The control unit can monitor the entire drying process without manual intervention, and monitor the status of various elements in the system or adjust the operating parameters.

As for the idea of the present invention, a method for gas-phase drying of kerosene transformer assembled at the installation site has been additionally proposed. The method includes the steps of: placing a dried transformer inside the oil tank of the transformer, using connecting pipes to connect the oil tank of the transformer with equipment for gas-phase drying outside the oil tank of the transformer, and carry out the gas-phase drying process with kerosene by drying the transformer in the oil tank of the transformer. Therefore, the vacuum chamber for stationary gas-phase drying is replaced with an oil tank of a transformer using the method according to the present invention, thereby reducing the cost of the device and achieving the goal, which is to implement the process of gas-phase drying of the transformer at the installation site of the transformer.

In the present invention, the gas phase drying process with kerosene includes a preparatory stage, a heating stage, a pressure reduction stage, a vacuum stage and a vacuum discharge stage, and in the vacuum discharge stage, the vacuum in the transformer oil tank is discharged using dry air, which is produced by a dry air generator, thereby ensuring thorough drying of the transformer and avoiding rewetting.

To ensure thorough drying of the transformer being processed, the present invention further includes a method for exhaustively determining the final water content of a transformer, including the following aspects:

1) the total duration of drying of the transformer;

2) the average final temperature of the transformer drying;

3) the final level of vacuum during drying of the transformer;

4) the final amount of water released during the drying of the transformer and

5) measurement of the water content in the dried transformer using the insulation test block.

It should be noted that both the above generalization and the detailed explanation below regarding the present invention are illustrative, which are intended to clarify the claimed invention rather than limit the scope of the present invention.

Brief Description of the Drawings

The drawings included in this application and its constituent parts provide an additional understanding of the present invention. Specific embodiments of the present invention, together with the description, are used to illustrate the fundamental characteristics of the present invention, with reference to the drawings in which

FIG. 1 illustrates a schematic diagram of the principle of operation of a stationary technological system for gas-phase drying with kerosene according to the prototype;

FIG. 2 illustrates a schematic diagram of the principle of operation of the system according to the present invention, which provides a gas-phase drying process for a transformer at the installation site;

FIG. 3 illustrates a flowchart of a gas phase drying method of a transformer with kerosene according to the present invention;

FIG. 4 illustrates a schematic diagram of the structure of a coarse filter according to the present invention.

Detailed Description of the Invention

The following is a further detailed description of the present invention with reference to the drawings.

To solve the problem of how to dry the transformer at the place of installation of the transformer, and the complexity of the design of the stationary gas-phase drying system, its high cost and environmental limitations, the present invention presents a system and method of gas-phase drying of kerosene transformers assembled at the installation site that can perform gas-phase drying of the transformer at the installation site of the transformer without infrastructure limitations.

In order to achieve the purpose of the present invention, in the present invention, an oil tank of a transformer incorporating a transformer instead of a vacuum chamber of a stationary gas-phase drying system is used, and gas-phase drying is carried out in a modular design, for which the corresponding system components are assembled and connected after arrival of the transformer and thereby execute gas-phase drying of the transformer at the place of installation of the transformer.

To better implement the concept of the invention and features of the present invention, the following is a detailed description of a specific embodiment of the present invention.

FIG. 2 illustrates a schematic diagram of the principle of operation of the system according to the present invention, which performs the gas-phase drying process of a transformer at the installation site. In the diagram, the single arrow represents the direction of the kerosene vapor, the double arrow represents the vapor return path, and the triple arrow represents the kerosene return path, while the many dotted

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rectangles represent modules of equipment for gas-phase drying. FIG. 2 presents: 11 - oil tank of the transformer, 12 - vacuum hole, 13 - inlet channel for dry air, 14 inlet channel for kerosene vapor, 15 - first exhaust kerosene channel, 16 - module for heating kerosene vapor, 17 - vacuum condensation module, 18 - cooling module, 19 kerosene return module, 20 - second exhaust kerosene channel, 21 - auxiliary heating device, 22 temperature signal inlet, 23 - bed, 24-evaporator, 25 - heat oil heater heater, 26 - waste oil tank, 27 - tank d I store oil, 28 collecting tank, 29 - condenser, 30 - vacuum unit assembly, 31 - water tank, 32 - water cooling unit, 33 - wastewater collection device, 34 - coarse filter, 35 control unit, 36 - pneumatic device.

The present invention provides a system (FIG. 2) for performing a gas-phase transformer drying process at an installation site, including: an oil tank 11 of a transformer that acts as a process container for the drying process, wherein the housing of a dried transformer is placed inside the oil tank 11 of a transformer; equipment for gas-phase drying, which is mounted outside the oil tank 11 of the transformer; and a connecting pipe for connecting the transformer oil tank 11 to the gas-phase drying equipment. In the system of the present invention, the oil tank of the transformer serves as a process container for replacing the vacuum chamber in a conventional stationary gas phase drying process system. Since in the present invention, an oil tank of the transformer is used instead of a vacuum chamber in a prototype stationary technological system for gas-phase drying, this saves installation costs (including infrastructure installation work) and the manufacture of a vacuum chamber, as a result of which the cost of the entire process system is significantly reduced drying in general. In actual production, using the transformer oil tank as a technological container for transformer drying simplifies the design of the entire drying process system as a whole, with a saving of about two million KMV investment in equipment such as a stationary vacuum chamber.

To ensure the characteristics of temperature and sealing of the transformer oil tank 11, a sealant is placed on the transformer oil tank 11 to seal it, and at the same time, with a coating of heat-saving layer outside, there is an auxiliary heating device 21 placed at the bottom and on the side wall of the oil tank transformer. When drying is completed, the heat-saving layer and the auxiliary heating device 21 outside the oil tank 11 of the transformer can be easily dismantled.

Auxiliary heating device 21 includes two parts: one is a tape electrical heating element for heating on the side wall of the oil tank of the transformer, which heat the side wall of the oil tank 11 of the transformer; the other is an infrared heating plate at the bottom of the transformer oil tank, which heats the bottom of the transformer oil tank 11. Auxiliary heating device 21 begins to heat the oil tank 11 of the transformer during the heating stage during the drying process and maintains heat until the drying is completed.

To further ensure that the transformer in the oil tank of the transformer can be thoroughly dried using the oil tank of the transformer, the oil tank of the transformer preferably can be enhanced and improved as follows: 1) increase the strength of the oil tank of the transformer itself, so that it does not experience residual deformation, being heated in a state of complete vacuum; 2) increase the reliability of all seals on the oil tank of the transformer, for example, high kerosene resistance, high temperature resistance; and 3) adjust the kerosene directing device in the oil tank of the transformer so that the kerosene vapors evenly circulate as they enter the oil tank of the transformer. All these aspects of improvement and adjustment are intended for the purpose of drying the transformer in the oil tank of the transformer with the help of the oil tank of the transformer in a high-temperature state.

In order to ensure the uniform circulation of kerosene in the entire system as a whole, there is a bed 23 with a certain height, which is placed under the bottom of the oil tank of the transformer. Usually the frame is made of metal materials with high compressive strength. In this embodiment, the frame is a steel frame. The upper surface of the steel frame is a sloping surface, and the sloping surface is inclined along the direction of the length of the transformer so that the oil tank of the transformer placed on the steel frame is inclined. Due to this arrangement, the oil discharge port on the transformer oil tank can be in the lower position, thereby ensuring that kerosene can circulate evenly throughout the system as a whole.

On the oil tank 11 of the transformer according to the present invention, a gas passage channel and an oil passage channel are connected to external gas-phase drying equipment, as described above. The gas passage channel includes an inlet channel 14 for kerosene vapor and a vacuum hole 12, and the inlet channel 14 for kerosene vapor is placed in the middle of the lower part of the side. 7 030334

side of the oil tank side of the transformer, while the vacuum hole 12 is located on top of the oil tank of the transformer.

At the same time in the inlet channel 14 for kerosene vapor place the guide pipe (not shown in Fig. 2), and through the guide pipe a couple of kerosene can reach the middle and bottom of the oil tank of the transformer. Preferably, a support partition (not shown in Fig. 2) is installed on the guide tube to divert kerosene vapors entering the guide tube, thereby avoiding local overheating of the insulation of the transformer housing at the kerosene vapor inlet.

The inlet duct 13 for dry air is placed on a vacuum pipe connected to the vacuum opening, and a dry air generator is connected to the inlet duct 13 for dry air (not shown in Fig. 2).

The dry air generator is designed to generate dry air when the condition of completing the drying of the transformer is reached, respectively, to which the vacuum in the oil tank of the transformer is released. The placement of the specified dry air generator solves the problem of re-wetting the dried transformer, thereby achieving thorough drying of the transformer, while in the stationary gas-phase drying process, the vacuum is released by the entry of ordinary air with a rather high moisture content.

The oil passage of the transformer oil tank according to the present invention includes a first exhaust kerosene channel 15 and a second exhaust kerosene channel 20, the first exhaust kerosene channel 15, which is placed in the side wall at a certain height from the bottom of the oil tank of the transformer, serves as the main channel for discharging oil from the oil tank of the transformer, while the second exhaust kerosene channel 20 is placed at the bottom of the oil tank of the transformer to ensure complete discharge of all the oil from the oil aka transformer.

Under normal circumstances, the first oil outlet kerosene channel 15 and the second oil outlet kerosene channel 20 of the transformer oil tank are installed, respectively, with a safety oil valve and a bottom oil valve. Although the diameter of the second kerosene outlet channel 20 is not very large, the second outlet kerosene channel 20 can be used to drain all the oil in the transformer oil tank. The diameter of the first kerosene outlet channel

15 is quite large, but since this discharge channel is at a certain height from the bottom of the transformer oil tank, the oil in the oil tank 11 of the transformer cannot flow completely from this discharge channel. In this system, the first exhaust kerosene channel 15 acts as the main oil outlet of the transformer oil tank.

In the gas phase process technology of the present invention, gas phase drying equipment located outside the transformer oil tank 11 is modular in order to simplify transportation and adaptation to a variety of topographic features at the site of the transformer. In accordance with the technical solution of the present invention, gas phase drying equipment can be made in the form of a modular modular structure to simplify the layout of the entire gas phase drying process system and facilitate the assembly of the relevant parts of the system, thereby reducing the cycle time in the gas phase drying process of the transformer.

In the present invention, the external gas-phase drying equipment is preferably divided into a plurality of modules including a vacuum condensation module 17, a kerosene vapor heating module 16, a kerosene return module 19, a cooling module 18, an oil storage tank 27, and a waste oil tank 26. They are placed according to topographic features at the place of installation of the transformer in a free order combination of modules. In this case, the cooling module 18 is connected respectively with the vacuum condensation module 17 and the kerosene vapor heating module 16, the module

16 heating the kerosene vapor is connected respectively with the kerosene return module 19 and the vacuum condensation module 17, the transformer oil tank 11 is connected respectively with the vacuum condensation module 17, the kerosene vapor heating module 16 and the kerosene return module 19, the oil storage tank 27 is connected respectively with the module 17 vacuum condensation and a kerosene vapor heating module 16, and a waste oil tank 26 are connected to a kerosene vapor heating module 16.

In this embodiment, to simplify transportation and outdoor work, the module

17, a vacuum condensation unit, a kerosene vapor heating unit 16, a kerosene return unit 19, and a cooling unit 18 can be implemented in a container arrangement. During operation, it is only necessary to open the container door, thereby significantly reducing installation operations and installation time. At the same time, since the above-mentioned order of combination of modules is used in gas-drying equipment, the installation and operation of the entire system becomes simple, easy, safe and reliable, thereby greatly increasing labor productivity.

From the connecting piping in this system, with the exception of the connecting piping for connecting the cooling module, which is a plastic hose with steel- 8 030334

All other connecting pipes are stainless steel sliding hoses. In other words, with the exception of the connecting piping of the cooling device, stainless steel is used as a material in all of the vacuum piping and the kerosene piping as a material to prevent rust from entering the kerosene and transformer, thereby guaranteeing the quality of the transformer. At the same time, a hose made of stainless steel can not only make the system look more pleasant and easy to use, but also provide greater flexibility and ease of placing the respective modules of gas-drying equipment relative to each other.

In this embodiment, the vacuum condensation module 17 mainly includes a vacuum unit assembly 30, a condenser 29 and a collection tank 28, the inlet channel of the condenser 29 being connected to the vacuum port 12 on the transformer oil tank 11, and its exhaust channel respectively connected to the vacuum unit assembly 30 and tank assembly 28; The kerosene vapor heating module 16 mainly includes an evaporator 24 and an oil-cooled heater 25, etc., the oil-cooled heater 25 being used to heat the evaporator 24, the inlet port of the evaporator 24 being connected to the kerosene return module 19, and its outlet the channel is connected to the inlet channel 14 for kerosene vapor on the oil tank of the transformer; the kerosene return module 19 mainly includes a coarse filter 34, etc., wherein the coarse filter inlet 34 is respectively connected to the first kerosene exhaust channel 15 and the second kerosene exhaust channel 20 of the transformer’s oil tank, and its exhaust pipe is connected to an evaporator 24 ; the cooling module 18 mainly includes a water tank 31 and a water cooling unit 32, and there are connecting pipes located between parts of the respective modules.

In addition, the vacuum condensation module 17 may additionally include a control device 35 for fully automatic control of the entire system. The control device 35 is connected respectively to the kerosene vapor heating module 16 and the kerosene return module 19, and other elements in the vacuum condensation module 17.

The control device 35 uses a computer system, and the control device automatically adjusts the state of all elements in the drying system according to the present invention or adjusts the operating parameters using a computer, thereby ensuring automatic operation, automatic registration, automatic monitoring, and so on.

The vacuum condensation module 17 further includes a pneumatic device 36 for driving a pneumatic valve. The pneumatic device 36 is connected respectively to the kerosene vapor heating module 16 and the kerosene return module 19 and connected to other elements of the vacuum condensation module 17 (since all the modules, kerosene vapor heating module 16, kerosene return module 19 and vacuum condensation module 17 have a pneumatic valve) .

The evaporator 24 in the kerosene vapor heating module 16 according to the present invention is an external single evaporator for the evaporation and distillation of kerosene. Since the installation site cannot be the same as during the drying process at the manufacturer, that is, with the transformer drying by using water vapor to convert kerosene into kerosene vapor, in the gas-phase kerosene drying system, an oil coolant heater 25 is placed for the transformer assembled on site mounting. The heater 25 of the oil coolant has a simple design, takes up little space and is economical to manufacture.

Another advantage is that, since the use of a steam supply system for heating kerosene easily causes pipeline corrosion, makes the heating pipes rusty, leading to steam leakage and increased production and maintenance costs, the present invention using an oil coolant heater can not only avoid adverse aspect of steam heating, but also to solve the real problem at the installation site of the transformer.

To adapt the present system to the environment at the place of installation of the transformer, the present invention uses a combined cooling module 18, which is equipped with a water cooling unit 32 and a water tank 31. This solves the problem of lack of a water source at the place of installation of the transformer and at the same time provides a cooling effect systems on site Due to the above design, the gas phase process technology of the present invention is not limited to the infrastructure at the site, i.e. it may not have an abundant water source and heat source, and nevertheless the gas phase process can be carried out.

In the present invention, the cooling water of the cooling module 18 is used during the heating process to cool a high temperature oil pump (which may be several, including a high temperature oil pump for transferring the heat transfer oil to the evaporator 24 and the high temperature oil pump for circulating kerosene in the evaporator 24) in the module 16 heating the kerosene vapor and the condenser 29 in the module 17 of the vacuum condensation. The oil storage tank 27 may store kerosene used during the drying process. Waste Oil Tank 26

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can store transformer oil from the transformer case, separated by distillation, when the transformer having transformer oil is dried.

The kerosene return unit 19 is connected to the first exhaust kerosene channel 15 and the second exhaust kerosene channel 20, respectively, and includes a coarse filter 34.

As shown in FIG. 4, the coarse filter includes a cavity 323. In the cavity 323, there is an inlet kerosene inlet 322 and an outlet kerosene inlet 319. In the cavity 323 there is a filtering net 320 for filtering out contaminants in liquid kerosene, and an outlet 315 is placed on the cavity 32 3 for external vacuuming designed to connect with an external vacuum system. The kerosene inlet pipe 322 is located on the side wall of the cavity 323 in a position opposite to the filtration grid 320. The inlet oil pipe 322 can be connected to the first exhaust kerosene channel 15 on the oil tank of the transformer. On the side wall of the cavity 323 there may be a second kerosene inlet port 310. The second kerosene inlet port 310 may be connected to the second outlet kerosene channel 20 on the transformer oil tank. The expansion of the cavity 32 3 back can form a collection chamber 314 suitable for containing liquid kerosene, and the external evacuation opening 315 is placed on the cavity in a place that corresponds to the collection chamber 314. In this embodiment, the filtration grid 320 has the shape of a half-cylinder with a bag. Filtration grid 320 divides the cavity 323 into a front section and a rear section. The rear section is a collection chamber 314, while the bottom of the front section is additionally equipped with a drain hole 321. At the bottom of the collection chamber 314, an exhaust kerosene pipe 319 is placed. pipe 319 after passing through the pump 318 for pumping kerosene. The collecting chamber 314 also has a liquid level regulator 316 for controlling the starting and stopping of the pump 318 for pumping kerosene. In this embodiment, an air inlet 311 with an air passage valve is located on the cavity 323. The front end of the air inlet 311 has a knee. On top of the cavity in the position corresponding to the filtration grid 320, place the hole. The opening is closed by a lid 312, which can be opened. The cover 312 has a viewing window. The cavity 323 is additionally covered with a heat-saving layer 317.

Below is an explanation of the specific operation of the coarse filter.

When the gas-phase drying equipment dries the transformer, the heated liquid kerosene flows out of the first kerosene outlet channel 15 or the second outlet kerosene channel 20 of the transformer’s oil tank and through the kerosene inlet pipe 322 or the second kerosene pipe 310 at the cavity 323 enters the coarse filter cavity 323, moreover, liquid kerosene, being filtered through the filtering network 320, is pumped by a pump 318 for pumping kerosene and leaves the exhaust kerosene pipe 319 Equipment for gas-phase drying in the recycling, and the excess liquid paraffin after filtration continues to remain in the collecting chamber 314, in which the liquid level controller 316 can control start-time stopping of the pump 318 for pumping according to the quantity of kerosene kerosene in the collecting chamber 314.

When the operator through the viewing window in the cover 321 sees that the filter screen 320 is clogged, he only needs to block the access of liquid kerosene entering the filtration device, activate the air inlet valve to open the air inlet 311, thereby dropping the vacuum in the cavity 323. After the intake process is completed air, unscrew the clamping screw 313, open the lid 312, remove and clean the filtering mesh 320. After cleaning the filtering mesh, perform the steps in the reverse order; There are the above parts and resume the operation of the coarse filter.

In the drying system according to the present invention, the middle of the lower part of the oil tank 11 of the transformer is additionally equipped with a temperature signal inlet 22, through which several temperature sensors can be inserted into the oil tank of the transformer. Temperature probes of temperature sensors are respectively inserted into different places on the transformer case. The temperature sensors are connected by output lines to the control device 35 and transmit a detected temperature signal to the control device 35, and then the control device 35 controls the operation of the entire drying system according to the data transmitted by the temperature sensors.

To better realize the features and advantages of the system according to the present invention, the following describes the installation procedure of a gas phase drying process system at the transformer assembly site, in conjunction with the layout of the system according to the present invention, which performs a gas phase drying process at the transformer installation site. The installation procedure is carried out as follows:

1) check all sealing parts on the oil tank of the transformer to ensure that they are heat-resistant and resistant to kerosene;

2) prepare kerosene and reserve consumables, such as oil for the pump, filtering mesh, and so on; kerosene and heat-transfer oil are added to tank 27 to store oil and heat- 10 030334

body 25 of the heat transfer oil according to the operating instructions of the device;

3) raise the oil tank of the transformer, bring the pre-cooked frame under its bottom so that the oil tank of the transformer in the direction of the length retains a certain degree of inclination;

4) after completing the assembly of the transformer case, insert the temperature sensors into the transformer case and connect the temperature sensors to the electrical parts of the system;

5) place a test block for insulation testing through a hatch with observation windows on the lower part of the transformer housing for recording the water content in the insulation test block after drying to evaluate the drying effect of the drying process;

6) perform the connection of pipelines between the drying devices and between the drying device and the oil tank of the transformer;

7) include all electrical control devices of the system;

8) install the external heat-saving material of the oil tank 11 of the transformer and mount an auxiliary heating device 21 at the bottom of the oil tank 11 of the transformer;

9) include the assembly 30 of the vacuum unit for evacuating the oil tank of the transformer and experience the degree of leakage of oil from the oil tank of the transformer.

After performing the above work, the system according to the present invention is then used to perform a gas-phase drying process with kerosene of a transformer placed in the oil tank of the transformer.

Regarding the idea of the present invention, a method for performing gas-phase drying with kerosene of a transformer assembled at the installation site is additionally presented. The method is a method that includes the steps of: placing a dried transformer inside the oil tank of the transformer, using connecting pipes to connect the oil tank of the transformer with equipment for gas-phase drying outside the oil tank of the transformer, and carrying out the gas-phase drying process with kerosene oil tank transformer. Therefore, a vacuum chamber for stationary gas-phase drying is replaced with an oil tank of a transformer using the method of the present invention, thereby reducing the cost of the device and achieving the goal of performing a gas-phase drying process of a transformer at the installation site of the transformer.

The method for drying a transformer according to the present invention is basically identical to a stationary gas-phase drying process, and the method is divided into five stages, respectively, as follows: preparatory stage, heating stage, pressure reduction stage, vacuum stage, and vacuum discharge stage. Below, these stages are explained with reference to FIG. 3

Stage 1: Preparatory Stage K using a vacuum block assembly 30 for evacuating the transformer oil tank 11 at room temperature;

Stage 2: Stage N heating, in which, when the pressure in the oil tank of the transformer reaches a certain value, the heater 25 of the heat-transfer oil begins to heat the evaporator 24, and in the evaporator 24 kerosene heats up with a transition to kerosene vapor that enters the transformer 11 , and after that the transformer body is gradually heated using the heat supplied by the kerosene vapor. On the other hand, kerosene vapors condense to form liquid after contact with the cold transformer case, and liquid is withdrawn from the bottom of the transformer oil tank (liquid kerosene automatically flows out of the first kerosene outlet or the second kerosene outlet, respectively, at the height of the liquid kerosene level at this time) then returns to evaporator 24 to be heated and re-circulated in it. On the other hand, as the transformer temperature rises, kerosene vapors will no longer fully condense, but will accumulate in the oil tank of the transformer, still existing in the form of gas. With a gradual increase in the temperature of the transformer housing in the oil tank of the transformer, the temperature of the insulating material in the transformer also gradually increases, and thus the moisture in the insulating material begins to evaporate and accumulate in the oil tank of the transformer in the form of water vapor. In addition, there could be a small amount of leaked air in the transformer oil tank, so that the gas in the transformer oil tank is a gas mixture. At the same time, the pressure in the oil tank of the transformer is also gradually increasing. The gas mixture then exits through the vacuum port 12 to the condenser 29 for condensation.

The condensed gas mixture is collected in the collection tank 28. Oil and water are separated as a result of sedimentation in the collection tank 28 due to the difference in specific weights, and water is removed to the waste water collection device 33, kerosene is reused and sent to the evaporator 24 to perform the second cycle, then as a non-condensable gas released into the atmosphere through the Assembly 30 of the vacuum unit. As a result of the above two circulation, the transformer housing gradually heats up. When the heating time reaches a certain value, the pressure in the oil tank 11 of the transformer and the pressure in the evaporator 24 will tend to equalize, and one or more intermediate pressure reduction cycles, namely, intermediate

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stage 1Pb pressure reduction, that is, the overlapping of the inlet channel for kerosene vapor in the oil tank 11 of the transformer. The reduction of pressure in the oil tank of the transformer to facilitate the flow of kerosene vapor into the oil tank 11 of the transformer, is performed using the module 17 of the vacuum condensation in the intermediate pressure reduction. If the transformer case has transformer oil, stop heating the transformer case, remove the liquid mixture and separate the transformer oil from kerosene according to different evaporation pressures of kerosene and transformer oil when the content of transformer oil in the liquid mixture in the evaporator 24 exceeds a certain amount (for example, above 10%) . Thus, after the purity of the kerosene has been increased, the process of heating the transformer case with kerosene continues.

Stage 3: Stage P of pressure reduction, in which, when the temperature of the transformer case reaches about 120 ° C and most of the moisture in the insulation material of the transformer has been removed, the pumping of liquid kerosene to the evaporator is stopped. The gas mixture in the oil tank 11 of the transformer is removed using the vacuum unit assembly 30 to re-evaporate the kerosene remaining in the insulating material.

Stage 4: Stage V vacuuming, in which the vacuum block assembly 30 is additionally used to create a deeper vacuum in the oil tank 11 of the transformer to provide additional evaporation of the kerosene and water remaining deep in the insulation material until the drying is completed.

Stage 5: the vacuum discharge stage, that is, the gas filling stage E, in which the dry air generator is first started and the vacuum in the transformer oil tank is released using dry air.

Finally, the inlet channel on the transformer oil tank (which is not connected to the temperature sensor) is opened, the test block is removed for the insulation test, the water content in the insulation element is determined, the whole process is completed.

As indicated above, compared with the stationary gas-phase drying process, the gas-phase drying process flow chart of the present invention is substantially identical to the stationary gas-phase drying process. However, since the internal infrastructure of the drying system for the gas-phase drying process of a transformer according to the present invention has been changed, and the external drying device has been improved and adapted, the corresponding control parameters of the drying process according to the present invention have been significantly changed.

To clarify the characteristics of the gas phase drying process according to the present invention, a description is now made regarding the main differences of the gas phase drying process according to the present invention and the stationary gas phase drying process. The main differences are that:

1) in the present invention, an oil tank of the transformer is used as a process container, which is much smaller in volume than a stationary vacuum chamber, so that the process steps require short-term maintenance of a high vacuum and the degree of high vacuum;

2) in the present invention, since the kerosene vapor generating device is placed very close to the transformer oil tank, the kerosene vapor supply line is no longer than that required for the stationary vacuum chamber, so that the present invention reduces energy loss during the vapor transfer process kerosene;

3) in the present invention, upon reaching the state of completion of drying of the transformer, in the technological scheme according to the present invention, a vacuum discharge stage, that is, stage E of filling with gas, is carried out, and at this stage, first start the dry air generator with a heater, and using dry air provide dry air into the oil tank of the transformer for vacuum relief in the oil tank of the transformer. The difference between this operation and the stationary process is that with stationary gas-phase drying, normal air is used to discharge the vacuum, and the dried insulation of the transformer is sensitive to rewetting due to a rather high moisture content in normal air. Therefore, the vacuum discharge stage in the method according to the present invention can prevent re-wetting of the dried transformer, thereby ensuring the quality of the drying of the transformer.

At the same time, to determine whether the dried transformer has reached the level of quality requirements for the drying process, the following method is used to determine: when the pressure in the oil tank of the transformer reaches atmospheric pressure, the inlet channel on the oil tank of the transformer is opened, the test unit for testing the insulation and determine the water content in the insulating element. In the present invention, a test block for insulation testing is designed to better determine the final water content in a transformer.

In addition to determining the water content in the transformer by detecting the water content in the test block for insulation testing, an exhaustive determination of the final water content in the transformer additionally requires consideration of the following aspects: the total drying time of the transformer; average final temperature of transformer drying; final vacuum level at

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drying the transformer; and measuring the final amount of water released during drying of the transformer.

Thus, the system and method according to the present invention additionally have the following advantages in addition to achieving the above objectives of the invention:

1) are able to shorten the production cycle of the transformer and, compared to the traditional method of drying at the installation site, the drying time is reduced by 1/2, thereby improving economic performance;

2) compared with the traditional method of drying at the place of installation, the heating is more uniform, the drying is more thorough;

3) compared to the traditional method of drying at the installation site, since kerosene fumes themselves are the best detergent that can wash out transformer oil during repairs and remove worn material and contaminants from the insulating material of the transformer, thereby increasing the purity of the transformer;

4) compared with the traditional method of drying at the place of installation, since the method of this system is convenient to use and has a high degree of automation, this reduces the operator's manual labor costs;

5) compared with the stationary gas-phase drying, since the oil tank of the transformer is used as a process container, there is no need to construct a vacuum chamber and does not require construction costs, thereby significantly reducing the cost of the drying process;

6) in comparison with the stationary gas-phase drying, the device according to the present invention is compact and compact, being simple for operation and monitoring;

7) in comparison with stationary gas-phase drying, the design in the form of a combination of modules is more flexible and more adapted for use. It can be used not only by the company itself to dry the transformer case, but it can also be used when overhauling and assembling the transformer is carried out.

As a result, the system and method presented by the present invention solve the problem of performing the process of gas-phase drying of a transformer at the place of assembly of the transformer. In addition to improving the quality of the drying process of a transformer, the present invention simplifies the design of a gas phase drying process system and makes the corresponding parts of the system easier to install and transport.

A variety of modifications and changes can be made without departing from the scope of the present invention, so all technical indications or contents of the above description, including those illustrated in the drawings, should be interpreted as explanatory, but not restrictive.

Claims (28)

CLAIM 1. A system for gas-phase drying with kerosene transformer at its installation site, containing equipment for gas-phase drying, characterized in that the equipment for gas-phase drying is designed as a single modular assembly for gas-phase drying or multiple modular assemblies for gas-phase drying, each modular assembly for gas-phase drying includes a vacuum condensation module (17), a kerosene vapor heating module (16), a kerosene return module (19) containing a pneumatic valve, and a cooling module (18) for cooling high the temperature of the oil pump in the module (16) heating kerosene vapor and condenser (29) in the module (17) vacuum condensation, tank (27) for storing oil and tank (26) for waste oil, these modules and tanks are connected by connecting pipes, connecting pipes are made with the possibility of their connection to the oil tank (11) of the transformer, which is designed to be a process container for the transformer in the process of gas-phase drying, while the equipment for the gas-phase The heat of drying contains a steel frame, the upper surface of which is an inclined surface for installing the transformer along the length direction of the transformer so that the transformer oil tank is inclined and the oil discharge channel is in the lower position, ensuring uniform circulation of kerosene. 2. The system according to claim 1, characterized in that the oil tank (11) of the transformer is additionally provided with a gas passage channel, an oil passage channel and an inlet port (22) of the temperature signal for connection with the equipment for gas-phase drying. 3. The system according to claim 2, characterized in that the gas passage channel contains an inlet channel (14) for kerosene vapor and a vacuum opening (12), with the inlet channel (14) for kerosene vapor placed in the middle of the lower part of the side surface of the transformer oil tank, and a vacuum hole (12) is placed on top of the oil tank (11) of the transformer. 4. The system according to claim 3, characterized in that in the inlet channel (14) for kerosene vapor is placed - 13 030334 the guide nozzle and the guide nozzle have a support wall for deviating towards the kerosene vapors entering the guide nozzle in order to prevent overheating at the inlet channel (14) for the kerosene vapors. 5. The system according to claim 3, characterized in that the inlet channel (13) for dry air is installed on a vacuum pipe connected to a vacuum hole (12), and a dry air generator is connected to the inlet channel (13) for dry air. 6. The system according to claim 2, characterized in that the oil passage channel contains a first exhaust kerosene channel (15) and a second exhaust kerosene channel (20), with the first exhaust kerosene channel (15) placed on the side wall at a certain height from the bottom of the oil tank transformer and serves as the main exhaust oil channel on the oil tank of the transformer during the gas-phase drying process, and the second exhaust kerosene channel (20) is placed at the bottom of the oil tank of the transformer to release all the oil from the oil tank trans ormatora. 7. The system according to claim 2, characterized in that the temperature signal inlet (22) is located in the middle of the lower part of the oil tank (11) of the transformer and through the temperature signal inlet (22) in the oil tank of the transformer, several temperature sensors can be placed These temperature sensors are inserted respectively into various parts of the transformer housing, while the gas-phase drying equipment contains a control device for automatic control of the system, and control device via its output lines connected to the respective temperature sensors, which transmit the detected temperature signal to the control device. 8. The system according to claim 1, characterized in that the cooling module (18) is connected respectively to the vacuum condensation module (17) and the kerosene vapor heating module (16), the kerosene vapor heating module (16) is connected respectively to the return module (19) kerosene and a vacuum condensation module (17), an oil tank (11) of the transformer is connected respectively to a vacuum condensation module (17), a kerosene vapor heating module (16) and a kerosene return module (19). 9. The system of claim 8, characterized in that the module (17) of vacuum condensation, the module (16) of heating kerosene vapor, the module (19) of returning kerosene and the module (18) cooling in the aggregate placed in the container layout. 10. The system of claim 8, characterized in that the module (17) of vacuum condensation and the module (16) of heating kerosene vapor are connected to the tank (27) for storing oil, and the tank (26) for used oil is connected to the module (16) heating kerosene vapor. 11. The system of claim 8, characterized in that a vacuum condensation module (17) contains an assembly of a vacuum unit (30), a condenser (29) and a collection tank (28), and the inlet channel of the condenser (29) is connected to the vacuum hole (12) on the oil tank (11) of the transformer, the exhaust channel of which connected, respectively, with the assembly (30) of the vacuum unit and the collection tank (28); the kerosene vapor heating module (16) contains an evaporator (24) and an oil-cooled heater (25), the oil-cooled heater (25) is used to heat the evaporator (24), the evaporator inlet channel (24) is connected to the kerosene return module (19), and its outlet channel is connected to the inlet channel (14) for kerosene vapor on the oil tank of the transformer; the kerosene return module (19) contains a coarse filter (34), the inlet pipe of the coarse filter is connected to the first exhaust kerosene channel (15) and the second exhaust kerosene channel (20) of the transformer, respectively, and the outlet pipe is connected to the evaporator (24); the cooling module (18) contains a water tank (31) and a water cooling block (32), while the components of the various modules are interconnected by connecting pipes. 12. The system according to claim 11, characterized in that the evaporator (24) is an external single evaporator for the evaporation and distillation of kerosene. 13. The system according to claim 1, characterized in that the connecting pipes are variable-length pipelines used to compensate for the length of the connections. 14. The system of item 13, wherein the connecting pipe for connecting the cooling module is a plastic hose with steel wire reinforcement. 15. The system according to claim 11, characterized in that the coarse filter (34) contains a cavity (323), and an inlet kerosene pipe (322) and a exhaust kerosene pipe (319) are placed in the cavity wall (323), and 323) there is a filtering mesh (320), and an opening (315) for external evacuation is placed on the wall of the cavity (323), which is intended for connection with an external vacuum system. 16. The system of clause 15, wherein the inlet kerosene pipe (322) is placed on the side wall of the cavity (323), and the second inlet kerosene pipe (310) is placed on the side wall of the cavity (323). 17. The system according to claim 16, characterized in that the inlet kerosene pipe (322) is connected to the first exhaust kerosene channel (15) on the oil tank of the transformer, and the second inlet ker is 14 030334 The blue pipe (310) is connected to the second outlet kerosene channel (20) on the oil tank of the transformer. 18. The system of clause 15, wherein the cavity (323) passes back to form a collection chamber (314) suitable for accommodating liquid kerosene, the opening (315) for external evacuation being placed on the wall of the cavity, which is formed by the collection chamber ( 314). 19. System p. 18, characterized in that the filter mesh (320) is placed in the middle of the cavity and opposite the kerosene inlet pipe (322), the filter mesh (320) separates the cavity (323) into the front section and the rear section, with the rear section makes up a collecting chamber (314), while in the bottom of the front section there is an additional drain hole (321), and the filtering mesh (320) has the shape of a half-cylinder with a bag. 20. System p. 18, characterized in that the exhaust kerosene pipe (319) is placed at the bottom of the collecting chamber (314), the pump (318) for pumping kerosene is placed at the bottom of the collecting chamber (314), so that after passing through the kerosene the pump (318) for pumping kerosene flowed out of the exhaust kerosene pipe (319), the regulator (316) of the liquid level to control the start and stop of the pump (318) for pumping kerosene is placed on the collecting chamber (314). 21. The system of clause 15, wherein the cavity (323) is covered with a heat-saving layer (317). 22. The system of clause 15, wherein the cavity (323) has an air inlet (311) with an air inlet valve, and the front end of the air intake (311) has a knee. 23. The system according to claim 15, characterized in that the top of the cavity on the wall is a hole in the position corresponding to the filtration grid (320), the hole is closed by the opening cover (312), and there is a viewing window in the cover (312). 24. The system according to claim 1, characterized in that it contains an auxiliary heating device (21) placed on the side wall of the oil tank of the transformer, which is a tape electrical heating element for heating, an auxiliary heating device (21) is placed at the bottom of the oil tank of the transformer and represents an infrared heating plate. 25. The system according to claim 1, characterized in that the steel frame (23), the upper surface of which is an inclined surface, is placed at the bottom of the oil tank of the transformer, and the inclined surface is inclined along the length direction of the oil tank of the transformer so that the oil is placed on it transformer tank is located with a slope. 26. System according to any one of claims 1 to 23, characterized in that it further comprises a control device for fully automatic control of the entire system using a computer, the control device monitoring the entire drying process without manual intervention and monitoring the state of various elements in system or setting operational parameters. 27. The method of gas-phase drying with kerosene transformer on the site of its installation, in which the equipment for claims for gas-phase drying with kerosene is used according to claims 1-26, containing steps for placing the dried-up transformer inside the oil tank (11) of the transformer, using connecting pipes and connecting the oil tank (11) a transformer with equipment for gas-phase drying outside the oil tank of the transformer; a gas-phase drying method is carried out with kerosene to perform the process of drying the transformer in the oil tank of the transformer, holding the preparatory stage, the stage of heating, in which kerosene is heated with the transition into kerosene vapors, which flow through pipelines into the oil tank (11) of the transformer, the stage of pressure reduction, the stage of vacuuming and the stage of vacuum relief, and at the stage of vacuum relief, a vacuum in the oil tank of the transformer dumped using dry air, which is produced by a dry air generator. 28. The method according to p. 27, characterized in that to ensure thorough drying of the processed transformer determine the final water content in the transformer, for which determine: 1) the total drying time of the transformer; 2) the average final temperature of the transformer drying; 3) the final level of vacuum during drying of the transformer; 4) the final amount of water released during the drying of the transformer; and 5) measure the water content in the dried transformer using an insulation test block. - 15 030334