JPH0217466Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Field of application of invention] The present invention relates to improvements in mobile transformers.

[Technical background of the invention]

BACKGROUND ART Conventionally, in substations and the like, when operation of an existing transformer is temporarily stopped due to maintenance inspection or an accident, a mobile transformer may be used as an emergency measure in place of the transformer. In this case, the mobile transformer is often loaded onto a vehicle and passes through urban areas, so when driving in urban areas, due to height restrictions, the high voltage bushing is first removed from the transformer and moved to the site. A mobile transformer was used, which was reassembled on site.

[Problems with background technology]

However, when assembling high pressure bushings on site,
Normally, the base of each phase high-voltage bushing is housed in the bushing mounting part provided in the transformer case, and the base of each phase high-voltage bushing is partitioned in an oil-tight manner using an insulating shield cylinder inside the case. vertically to each bushing mounting part, then connect a vacuum pump to the lubrication valve provided on the bushing mounting part, use this vacuum pump to reduce the pressure inside the bushing pocket to the specified pressure, and then degas it. The high-pressure bushing was assembled by filling the bushing installation chamber with insulating oil. When reassembling the bushings as described above, the installation chambers of each phase bushing were depressurized one by one with a vacuum pump while being filled with insulating oil, so reassembling the high-pressure bushings of each phase was extremely difficult. It was time consuming and troublesome. Another disadvantage is that each time the mobile transformer is used, degassed insulating oil must be prepared and transported in a separate vehicle. In particular, if there is no power source to drive the vacuum pump at the site, it is not possible to reduce the pressure inside the bushing installation chamber. Because the bushing was attached to the bushing mounting part after the live base of the bushing was immersed in oil, if air bubbles remained on the surface of the insulation shield cylinder that forms the mounting chamber or on the surface of the base of the bushing, the insulation of the insulating oil In addition to degrading performance, the bubbles caused harmful partial discharge when voltage was applied to the equipment, and there was a risk of deteriorating and damaging the insulating shield tube and bushing.

[Purpose of invention]

The present invention eliminates the above-mentioned drawbacks and makes it possible to fill the installation chambers of high-pressure bushings for each phase with insulating oil without using a vacuum pump on-site and in a bubble-free state, thereby facilitating the installation of high-pressure bushings on-site. The object of the present invention is to provide a mobile transformer that can quickly and easily perform the following steps without degrading the performance of the insulating oil.

[Summary of the idea]

The present invention includes a conservator that communicates with the main body chamber inside the transformer case, a conservator that communicates with the switching switch chamber partitioned inside the transformer case, and a conservator that communicates with each phase of the transformer case on the cover of the transformer. An oil storage tank that communicates with the bushing installation chamber provided in the high-pressure bushing installation part is individually formed and arranged, and each installation chamber of each phase high-pressure bushing and the oil storage tank are individually connected by piping. , after the high-pressure bushings of each phase are installed, the mounting chambers of the bushings are simultaneously filled with insulating oil deaerated from an oil storage tank.

[Example of idea]

Embodiments of the present invention will be described below with reference to the drawings.

In FIGS. 1 to 5, reference numeral 1 denotes a case of a mobile transformer, which includes a main body chamber 1a in which a transformer main body and a switching switch (not shown) are partitioned in an oil-tight manner by insulating oil; They are individually stored together with insulating oil in the switching switch 1b. Reference numeral 2 denotes a mounting portion for each phase high voltage bushing 3, which is formed on the side wall of the transformer case 1 in an outwardly bulging state, and has a storage chamber 4a inside which stores the base charging portion of the high voltage bushing 3.
4c to 4c are partitioned in an oil-tight manner within the case 1 by an insulating shield cylinder. 5 is a cover of the transformer case 1; 6 is a conservator for the main body chamber that is attached to the cover 5 and communicates with the main body chamber 1a inside the transformer case 1; This is to contain the oil when the insulating oil expands due to changes in outside temperature or changes in the transformer load, and is communicated with the inside of the case 1 through a communication hole 7 drilled in the cover 5, as shown in Figure 5. are doing. Reference numeral 8 denotes a conservator for a switching switch chamber formed on the upper surface of the conservator 6 via a partition wall, and communicates with the switching switch chamber 1b in the case 1 through an oil conduit 9. Reference numeral 10 denotes an oil storage tank that is integrally formed with both conservators 6 and 8 via a partition wall on the rear side of the conservators 6 and 8 (on the right side in FIG. 7).
0 stores insulating oil to be supplied to storage chambers 4a to 4c provided in the mounting portion 2 of the high-pressure bushing. The oil storage tank 10 and each storage chamber 4
As shown in FIG. 1, a to 4c are the oil pipes 1
They are communicated with each other by 1a to 11c and a branch pipe 11d. The oil supply pipe 11a communicates the oil storage tank 10 and the storage chamber 4a via a stop valve _V6 and an oil filling valve _V1 , and one of the oil supply pipes 11b communicates with the oil supply pipe 11a through a branch pipe 11d.
The other end is connected to the storage chamber 4b via an oil drain valve _V4 and an oil filling valve _V2 , and one side of the oil feed pipe 11c is connected to a branch pipe 11d, and the other side is connected to the storage chamber 4c through an oil filling valve _V3 . Furthermore, each storage chamber 4a to 4c has a stop valve between it and the upper part of the oil storage tank 10.
The exhaust pipes 11e to 11g communicate with each other via _V7 . In addition, as shown in FIG. 7, in the center of the upper surface of the oil storage tank 10, a metal bellows 12 is connected to the inside of the tank 10, and a guide plate 13 attached to the upper end of the metal bellows 12 is inserted into a guide rod 14, so that the metal bellows 12 can be moved in the vertical direction. It is elastically attached to the holder. As shown in FIG. 8, reference numeral 15 denotes an indicator plate whose upper end is fixed to the top of the guide bar 14 and hung downward, and an indicator scale 16 is provided on the surface of the indicator plate, which is attached to the end of the guide plate 13. The degree of expansion and contraction of the metal bellows 12 is measured by indicating the predetermined position of the indicator scale 16 using the arrow viewing plate 17. Reference numeral 18 denotes a cover box mounted on the oil storage tank 10 to cover the metal bellows 12, and a window hole 18a is provided at a position corresponding to the indicator plate 15. 19 is an exhaust plug attached to the top of the metal bellows 12.

In the figure, 20 is an oil conduit pipe that connects the main body chamber 1a in the transformer case 1 and the cooling device 21.
The insulating oil cooled from 1 is fed to the lower side of the main body chamber 1a through an oil conduit (not shown). 22, 23
24 is an oil tank for storing the insulating oil in the main body chamber 1a and switching switch chamber 1b of the transformer case 1 when it is blown out due to a transformer accident, 24 is the electric operating mechanism room of the switching switch, and 25 is also a control 26 is a trailer carrying a mobile transformer, 27 is a diaphragm attached to the main body conservator 6, 28 is an oil level gauge attached to the top surface of the oil storage tank 10, and an exhaust valve is installed at the upper end. _V5 is installed in communication with the inside of the oil level gauge 28. Reference numerals 29 and 30 indicate oil drain valves respectively attached to the conservator 6 for the main body chamber and the conservator 8 for the switching switch chamber, and 31 indicates a low pressure bushing.

Next, the operation will be explained. First, the high-voltage bushings 3 of each phase are attached to the bushing mounting portions 2, and then the storage chamber 4 for housing the live parts of the base of the bushings is installed.
The case where insulating oil is filled in a to 4c will be explained. First, remove the blind lid (not shown) that is fixed to the bushing mounting part 2, and remove the insulating oil filled in each storage chamber 4a to 4c (this insulating oil is the insulating shield cylinder forming the storage chambers 4a to 4c). , which is attached to the bottom of the storage chambers 4a to 4c to protect the conductive part connected to the live part of the base of the bushing), is removed using a manual pump, and after emptying each storage chamber 4a to 4c, the high pressure bushings 3 of each phase are removed. The base portions are stored in the respective storage chambers 4a to 4c, and the high-pressure bushings 3 of each phase are fixed to the bushing mounting portion 2 in an upright position. In this state, open stop valve V ₆ and
Next, the oil supply valves V ₁ to V ₃ provided close to each of the storage chambers 4a to 4c are opened, and then the stop valve V ₇ is opened to supply oil pipes 11a to 11c and The degassed insulating oil in the oil storage tank 10 is simultaneously filled through the branch pipe 11d. At this time, the oil storage tank 10 is attached to each storage chamber 4a to 4c.
Since the insulating oil is located above the storage chamber 4a,
to 4c naturally. Each storage room 4a to 4
Confirm that the appropriate amount of oil has been applied to c using an oil level gauge (not shown) attached to the mounting portion 2 of each bushing. During oil filling, the air in each storage chamber 4a to 4c flows into the oil storage tank 1 through exhaust pipes 11e to 11g.
Remains above 0. In addition, each storage room 4a to 4c
In order to prevent air from penetrating the insulating oil, it is preferable not to lubricate the insulating oil suddenly, but to do so gradually by appropriately operating the lubrication valves V ₁ to _{V 3} . After the oil filling is completed, the oil filling valves V ₁ to _{V 3} are closed and the transformer starts operating.

When the operation of the transformer is finished, the high-voltage bushings 3 of each phase are removed from the bushing mounting part 2, and a blind cover is attached to this mounting part 2. At this time, if the amount of oil in each storage chamber 4a to 4c is low, the oil fill valve
After opening V ₁ to _{V 3} and filling an appropriate amount of oil from the oil storage tank 10, the oil filling valves V ₁ to _{V 3} are closed again. After this, stop valve _V7 is also closed.

When filling the oil storage tank 10 with deaerated insulating oil, proceed as follows.

First, the exhaust valve _V5 and the oil drain valve _V4 are opened, and all of the insulating oil in the oil storage tank 10 is drained to the outside from the oil drain valve _V4.Then , the oil drain valve _V4 is equipped with a vacuum cleaner. Connect the lubrication hose of the oil machine and the vacuum hose of the vacuum oil purifier to exhaust valve _V5 . In this state, the vacuum oil purifier is operated to fill the oil storage tank 10 with degassed insulating oil. Once the insulating oil has filled the oil storage tank 10 to a certain extent (confirmed by the oil level gauge 28), the exhaust valve _V5 and the exhaust plug 19 provided at the top of the metal bellows 12 are opened, and the insulating oil flows through these exhaust valves.
Oil is continued to be supplied from V ₅ and the exhaust plug 19 until overflow occurs, and the air in the oil storage tank 10 is exhausted. At this time, adjust the amount of oil supplied so that the height of the metal bellows 12 corresponds to the oil temperature, close the exhaust valve _V5 and the exhaust plug 19, and finally close the oil drain valve _V4 to store the oil. Lubricating the tank 10 is finished.
Further, when the oil storage tank 10 is filled with oil, the stop valve _V6 is closed, so that insulating oil is not supplied to each of the storage chambers 4a to 4c.

[Effect of idea]

As explained above, the present invention includes a conservator that communicates with the main body chamber in the transformer case, and a switching switch that is oil-tightly partitioned from the main body chamber and formed in the transformer case on the cover of a mobile transformer. A conservator that communicates with the chamber and the back of both conservators.
An oil storage tank for storing deaerated insulating oil to be fed to a storage chamber for storing the base of the bushing provided in the mounting part of the high-pressure bushing is integrally configured via a partition wall, and the oil storage The tank and the storage chamber formed in the mounting part of the high-pressure bushing are connected via piping via the required number of oil fill valves and stop valves, and the oil storage tank has an internal structure that absorbs and relieves the pressure generated in the tank. Since it is constructed by attaching a metal bellows that allows the

The present invention eliminates the need to prepare insulating oil to be filled in the base storage chamber of the high-voltage bushing in a separate vehicle and operate it together with the mobile transformer every time the mobile transformer is used. By making effective use of the empty space on the transformer cover, an oil storage tank filled with insulating oil to be supplied to the storage chamber is installed on the transformer cover in parallel with the conservator. This method does not require a special vehicle to transport the insulating oil, nor does it require any lubrication means, making it easy and economical to transport degassed insulating oil used when installing high-voltage bushings in mobile transformers. It can be carried out. Moreover, the oil storage tank is
Since it can be installed by effectively utilizing the narrow space on the transformer cover, it is convenient because no special installation space is required.

Further, the oil storage tank is installed at a position above each base storage chamber of the high pressure bushing,
Since it is connected to each of the storage chambers by piping, when lubricating the storage chambers with the insulating oil in the oil storage tank, it is possible to simultaneously lubricate multiple storage chambers by effectively utilizing the natural head. Lubricating work into the base storage chamber of the high-pressure bushing can be performed quickly and easily. Moreover, as the lubrication work is speeded up, the usage efficiency of the mobile transformer can be significantly improved. Furthermore, since the oiling process uses the natural head, unlike conventional oiling operations, there is no need for a vacuum pump to reduce the pressure inside the storage chamber or power supply equipment to drive it. This is no longer necessary, and the lubrication work can be performed smoothly and efficiently in a natural state.

Furthermore, the oil storage tank and each storage chamber are equipped with the required number of oil fill valves and shutoff valves in the middle of the piping, so during oil filling work, insulation can be maintained by operating each of the valves as appropriate. Since the rapid delivery of oil can prevent air from penetrating into the degassed insulating oil, the insulating oil that is lubricated into the storage chamber that houses the base of the high-pressure bushing will not reduce its insulating properties. It is possible to lubricate well without any problems.

In addition, a metal bellows is installed inside the oil storage tank to reduce pressure rise.
Even if the pressure inside the oil storage tank increases due to an increase in the oil temperature in the oil storage tank or due to air remaining in the oil storage tank after insulating oil is filled into the storage chamber, the metal bellows will prevent Since the pressure can be absorbed and relaxed well,
It is possible to reliably improve the safety associated with the increase in pressure within the oil storage tank.

[Brief explanation of the drawing]

Figure 1 is a rear view showing the main parts of the transformer of the present invention, Figure 2 is a plan view, Figures 3 and 4 are a front view and plan view of the transformer of the present invention, and Figure 5 is a view of various conservators. FIG. 6 is a plan view as well, FIG. 7 is a cross-sectional view taken along line A-A in FIG. 6, and FIG. 8 is a side view showing how the metal bellows are installed. , FIG. 9 is a plan view as well. 2... Bushing mounting part, 3... High pressure bushing, 4a to 4c... Storage chamber, 6... Main body room conservator, 8... Switching switch room conservator,
10...Oil storage tank, 12...Metal bellows,
11a to 11c...Oil pipe, 11e to 11g
...Exhaust pipe, V ₁ to V ₃ ... Oil filling valve, V ₄ ... Oil drain valve, V ₅ ... Exhaust valve, V ₆ , V ₇ ... Stop valve, 19...
...exhaust plug.

Claims (1)

[Scope of claims for utility model registration] (1) On the cover 5 of the mobile transformer, the transformer case 1
a conservator 6 communicating with the main body chamber 1a inside;
In the transformer case 1, a conservator 8 communicating with the main body chamber 1a and an oil-tightly partitioned switching switch chamber 1b is arranged in a straight line. Insulating oil is stored in each of the storage chambers 4a to 4c in the mounting section 2 formed by bulging the side wall of the transformer case 1 outward to accommodate the base live parts of the high-voltage bushings 3 of each phase of the transformer. The oil storage tank 10 is located above the storage chambers 4a to 4c,
Storage chambers 4a to 4c, which are arranged in parallel with each of the conservators 6 and 8 via a partition wall, and which house the oil storage tank 10 and the base charging portions of the high-pressure bushings 3 of each phase, each have an oil supply valve V _{1 .} A mobile transformer characterized in that the transformer is individually and communicatively connected to each other via stop valves V ₆ and V ₇ . (2) The mobile transformer according to claim 1, wherein the oil storage tank is equipped with a metal bellows that absorbs and relieves the pressure inside the tank.