JPH1022135A - Cooling system for stationary induction apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling system for stationary induction apparatus which can suppress heat dissipation into a room even when a stationary induction apparatus is operated in an overloaded state or immediately after the apparatus is stopped and can prolong the operating time of the apparatus in the overloaded state. SOLUTION: A cooling system is constituted of a stationary induction apparatus 3 installed in the equipment chamber of an underground or indoor substation, a first coolant which fills up the main body tank of the apparatus 3 and directly cools the winding and iron core of the apparatus 3, a heat exchanger 6 which cools the first coolant with a second coolant, and a heat dissipation means which dissipates the heat of the second coolant to the outside of the equipment room. To the cooling system, a heat insulating cover 15 which covers at least part of the tank 2 of the apparatus 3, an air blower 12 which makes the cold air in the equipment chamber in which the apparatus 3 is installed to flow through the space between the cover 15 and tank 2, and an air duct 17 which introduces the cold air passed through the space between the cover 15 and tank 2 to the outside of the equipment room without discharging the cold air into the room.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling system for a static induction device, and more particularly to a cooling system for a static induction device installed in an underground substation or an indoor substation.

[0002]

2. Description of the Related Art A cooling system for a static induction device installed in an ultra-high voltage underground substation or an indoor substation, which has been generally employed, includes a first refrigerant,
For example, the cooling medium such as oil or gas is filled, the windings and the iron core are directly cooled by the first coolant, and the first coolant is cooled by the second coolant via a cooling system having a heat exchanger. It is usually formed so that it is cooled by the refrigerant.

As described above, most of the heat generated by the loss of the stationary induction device installed in the ultra-high voltage underground substation is transmitted to a cooling system having a heat exchanger, that is, a pump, piping and a roof for circulating a cooling medium. It is disposed of outdoors by the installed cooling tower. However, a part of the generated heat is radiated into the room mainly by radiation and convection, and the temperature of the room rises, because there is a difference between the temperature of the stationary induction device main body tank and the surrounding temperature. If the room temperature rises excessively, it may hinder maintenance and inspection or adversely affect the equipment.
The hot air must be ventilated to the outside (or outside the building).

[0004] In underground substations, reduction of the floor height of the equipment installation room has a great effect on cost reduction during building construction. Therefore, recently, optimal design of equipment in consideration of floor height reduction has been promoted. This floor height reduction includes downsizing of transformers and auxiliary equipment including their cooling equipment.However, the floor height of the equipment installation room is limited by ducts such as ventilation equipment and cooling water piping laid on the ceiling. However, the height must be such that it does not hinder the loading and unloading of transformers.

[0005] Particularly recently, large-capacity gas-insulated transformers have begun to be used instead of conventional oil-filled transformers in ultra-high-voltage underground substations, mainly for disaster prevention reasons. Dissipation of heat and enlargement of ventilation equipment for discharging the heat outside the room, especially enlargement of ventilation ducts, have become a bigger problem than ever before. This is because gas-insulated transformers generally have a higher operating temperature than conventional oil-immersed transformers, and because the transformer main tank is a multi-segment type, the surface area increases and the amount of heat dissipated into the room by radiation increases. This is to increase.

In order to solve this problem, a heat insulating material is provided on the entire surface or a part of the outside of the tank of the stationary induction device installed underground or indoors to reduce the heat radiation from the stationary induction device to the room, The heat generated by the heat loss is discharged to the outside of the building via a heat exchanger for indirectly cooling the refrigerant that directly cools the windings and the iron core. Incidentally, as related to this, for example, Japanese Patent Application Laid-Open No. 5-6827 is mentioned.

[0007]

With the cooling system for a stationary induction device formed as described above, the heat radiation to the building is reduced, and the heat generated by the loss of the equipment is passed through the heat exchanger. Since it is released outside the building, the ventilation duct of the building can be made smaller and the floor height can be reduced to the required height of the equipment, and there is no particular problem during normal operation, however, In some cases, if one transformer fails or becomes inoperable, another transformer may be temporarily overloaded. At this time, the following problem may occur.

That is, when the transformer is overloaded, the current flowing through the windings increases, and naturally the amount of heat generated by the loss also increases. In particular, large-capacity gas-insulated transformers with a capacity of 300 MVA, which have recently begun to be applied to ultra-high-voltage underground substations, have inherently low heat capacity of the gas, so the temperature rise of the gas during overload operation, structures such as windings Temperature rise is remarkable. Therefore, in a large-capacity gas insulated transformer, it is a problem to extend the overload operation time without losing reliability.

Here, as described above, when most of the tank is covered with a heat insulating material, the temperature rise inside the tank becomes more severe, the life of the insulator is shortened, and the reliability is reduced. This causes a problem that the overload operation time is further reduced. Of course, the same occurs when a failure occurs in the cooling system. That is, the conventional cooling system of this type does not consider the case where the large-capacity gas insulated transformer must be overloaded or the reliability of the gas cooler or the blower deteriorates when it fails. Was.

[0010] The present invention has been made in view of the above, and its object is to solve the problem even during overload operation.
Another object of the present invention is to provide a cooling system for a stationary induction machine that can suppress heat dissipation into a room even immediately after a stop and extend the overload operation time.

[0011]

That is, the present invention provides a stationary induction device installed in an equipment room of an underground or indoor substation, and a winding of the stationary induction device which is filled in a main body tank of the static induction device. A first refrigerant for directly cooling the iron core;
In a cooling system for a stationary induction electric machine including a heat exchanger that cools the first refrigerant with a second refrigerant, and a heat disposing unit that disposes of the heat of the second refrigerant outdoors, the cooling system includes: A heat-insulating cover that covers at least a part of the main body tank of the stationary induction device, a blower that circulates cool air in an equipment room in which the static induction device is installed in a gap between the heat-insulating cover and the main body tank, and passes through the gap. An air guide path for guiding the cooled air to the outside of the equipment room without discharging it into the equipment room is provided to achieve the intended purpose.

Further, a stationary induction device installed in an equipment room of an underground or indoor substation, and a first refrigerant filled in a main tank of the stationary induction device and directly cooling a winding and an iron core of the stationary induction device A heat exchanger that cools the first refrigerant with a second refrigerant; a heat disposal unit that disposes of the heat of the second refrigerant outdoors; In a cooling system for a stationary induction electric machine having an exhaust wind tunnel for exhausting outdoors, a heat insulating cover covering at least a part of a main body tank of the stationary induction electric appliance, wherein the cooling system is provided between the heat insulating cover and the main body tank. A blower that circulates cool air in the equipment room in which the stationary induction device is installed in the gap, and a wind guide path that guides the cool air that has passed through the gap to the exhaust wind tunnel without discharging the cool air into the equipment room. That.

Also, a stationary induction device installed in an underground or indoor substation, a first refrigerant for directly cooling the windings and the iron core of the stationary induction device, and a second refrigerant for cooling the first refrigerant. In a cooling system for a stationary induction electric device including a heat exchanger and heat disposing means for disposing of the heat of the second refrigerant to the outside, a tank surface water cooling for cooling a main tank surface of the stationary induction electric device is provided in the cooling system. Means, said second
And a bypass for supplying a refrigerant from the system for supplying the refrigerant to the tank surface water cooling means. In this case, the tank surface water cooling means is formed by a water cooling jacket or a water cooling pipe.

That is, according to the cooling system for a stationary induction device formed as described above, a heat-insulating cover that covers at least a part of the main body tank is provided, and a blower is provided in a gap between the main body tank and the heat-insulating cover. The cooler circulates cool air in the equipment room, and has an air guide path for guiding the cool air passing through the gap to the outside of the equipment room. And the heat is discharged outside from the exhaust wind tunnel without being dissipated into the equipment room. In other words, since the heat of the local heat source can be discharged outside without temporarily dissipating it indoors, the air supply / exhaust equipment, especially the wind tunnel, is significantly reduced in size, and the heat dissipation into the equipment room is reduced. Instead of suppressing the heat radiation from the main tank, the tank surface is forcibly cooled, so the temperature of the gas and the structure of windings and other structures are increased even during overload operation or when auxiliary equipment is stopped. Therefore, overload operation time can be extended and reliability can be improved.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on illustrated embodiments. FIG. 1 shows a stationary induction device provided with the cooling system and its surroundings. This figure shows an example in which the cooling system for a stationary induction device is applied to an ultra-high voltage underground substation.

In the figure, reference numeral 1 denotes an equipment room in which a transformer and the like are installed in an underground substation. Reference numeral 2 denotes a main tank of a gas-insulated transformer installed in the equipment room 1. Although the main tank of the gas-insulated transformer for one phase is shown here, actually three units constitute a three-phase gas-insulated transformer 3 having a capacity of 300 MVA. The main body tank 2 is formed in a vertical cylindrical shape, and a lead duct 4 is provided on a side portion thereof. This lead duct is a lead duct for drawing out a primary lead wire connected to the primary winding. Although not shown, the main body tank 2 contains a winding and an iron core, and SF6 gas serving as an insulating and cooling medium.

During operation, heat due to loss is generated in the iron core and the winding. Further, a blower 5 and a gas-water heat exchanger 6 are connected to the main body tank 2 via a pipe 7, and the blower 5 circulates SF6 gas to cool the windings and the iron core. Here, the SF6 gas, which has been heated to a high temperature by removing heat from the windings and the iron core, exchanges heat with the cooling water in the gas-water heat exchanger 6 to have a low temperature, and is sent again into the main body tank 2 by the blower 5. The cooling water, which has been heated to a high temperature by the heat exchange in the gas-water heat exchanger 6, is cooled by the cooling water pipe 8 and the pump 9 to the outside air by the cooling tower 10 installed on the roof. The heat is sent to the heat exchanger 6.

Most of the heat loss of stationary induction devices such as transformers installed in underground substations is disposed of outdoors by such a water cooling system. However, since the surface temperature of the stationary induction device main body tank is generally higher than the ambient temperature in the equipment installation room, heat is radiated from the main body tank surface into the equipment room by radiation and convection. In addition, since substations have losses in equipment other than static induction equipment, air supply and exhaust equipment are provided to discard these heats outside the room and maintain the temperature and humidity in the room within specified ranges. .

This embodiment is also provided with such a supply / exhaust facility. That is, 11 is an air supply wind tunnel for introducing outside air into the equipment room 1, and 12 is a blower. Also, 13, 1
Reference numeral 4 denotes an exhaust wind tunnel and a blower for discharging the air in the equipment room 1 to the outside. Here, since the large-capacity gas-insulated transformer 3 of the present embodiment has a higher operating temperature than the oil-filled transformer conventionally used in general, the temperature of the surface of the main body tank 2 and the ambient temperature in the equipment room 1 are high. And the difference becomes large. Further, as described above, since a large-capacity gas-insulated transformer is divided so as to have a capacity of about 100 MVA per tank, the surface area of the main tank increases. As a result, the amount of heat dissipated indoors becomes enormous, and the exhaust wind tunnel becomes large in order to dispose the heat outdoors. As the size of the exhaust wind tunnel increases, the floor height of the equipment room increases, which causes a problem that the construction cost of the substation building increases significantly.

In order to solve this problem, in this embodiment, a heat insulating cover 1 covering at least a part of the main body tank 2 is provided.
5, a blower 16 for circulating cool air in the equipment room 1 in a gap between the main body tank 2 and the heat insulating cover 15, and a cool air passing through this gap without discharging the cool air into the equipment room 1.
An air guide path 17 is provided to guide the air to the outside, and this air guide path 17 is connected to the exhaust air tunnel 13.

The heat-insulating cover 15 is made of a thin plate such as stainless steel. Thereby, the main body tank 2 is cooled by the cool air in the equipment room 1, and the heat is discharged outside from the exhaust air tunnel 13 without being diffused into the equipment room 1. That is, in this embodiment, since the heat of the local heat source can be discharged outside without temporarily dissipating it indoors, the size of the air supply / exhaust equipment, especially the wind tunnel, is greatly reduced.

Further, in the present embodiment, the surface of the tank is forcibly cooled instead of suppressing the heat radiation from the main tank 2 in order to reduce the heat dissipation into the equipment room 1. Therefore, even when the overload operation is performed or the auxiliary device is stopped, the temperature of the gas or the structure such as the winding is not increased, so that the overload operation time can be extended and the reliability can be improved. That is, according to the present embodiment, it is possible to reduce the heat dissipation into the room without sacrificing the reliability during the overload operation or the stop of the auxiliary device.

In the present embodiment, an example is shown in which a heat insulating cover is provided for each of the main body tanks 2 of the gas insulated transformer 3, but this is not always the case.
For example, it goes without saying that a heat insulating cover that covers a plurality of main tanks 2 at a time may be used.

Next, another embodiment of the present invention will be described with reference to FIG. In the figure, the same reference numerals are given to the same components as those in the above-described embodiment, and the detailed description will be omitted. This embodiment is different from the above-described embodiment in that the main body tank 2 is cooled with water. That is, 18
Is a cooling pipe wound around the main body tank 2 and is connected to an air-cooled cold water producing apparatus 19. Here, if a copper pipe is used as the cooling pipe 18 and the main tank 2 is soldered to silver, the thermal contact is improved.

With this configuration, the heat of the main body tank surface 2 is transferred by the cooling water in the cooling pipe 18 to the air-cooled chilled water producing device 19, and further, the air-cooled chilled water producing device 19 causes By exchanging heat with cold air, heat is transferred to the blown air. The blown air is discharged from the exhaust air tunnel 13 to the outside of the equipment room 1 via the air guide path 17 without being discharged into the equipment room 1.

As described above, according to the present embodiment, similarly to the first embodiment, the heat of the local heat source is discharged to the outside without temporarily dissipating the heat into the room. It is possible to greatly reduce the size. Further, since the tank surface is also forcibly cooled in this embodiment, the temperature of the gas or the structure such as the winding does not increase even during the overload operation or when the auxiliary device is stopped. Therefore, the present embodiment has the same effect as the first embodiment.

In this embodiment, the cooling pipe 18 is connected to the air-cooled cold water producing apparatus 19, but the gas-water heat exchanger 6
Of the cooling water pipe 8 connecting the gas and water heat exchanger 6 and the cooling pipe 1 of the main tank 2
8 may be connected in parallel. With this configuration,
Although the temperature of the surface of the main body tank 2 is slightly higher than when the air-cooled chilled water production device 19 is used, there is an advantage that the system is simplified.

Further, in this embodiment, the cooling pipe is used for cooling the surface of the main body tank with water. However, as shown in FIG. The jackets 20a and 20b may be formed so that the cooling water flows through the jackets. In addition, 21 is a jacket connection pipe.

As described above, in the cooling system for the stationary induction device formed as described above, heat is discharged outside without being radiated into the equipment room. That is, since the heat of the local heat source can be discharged outside without temporarily dissipating it indoors, the heat radiation from the main body tank should be suppressed to reduce the heat dissipation to the equipment room as in the conventional case. Rather, the main tank surface is forcibly cooled, so even during overload operation or when auxiliary equipment is stopped, the temperature of gas, windings and other structures are not increased, and the overload operation time is extended. Reliability can be improved.

[0030]

As described above, according to the present invention, heat dissipation to the room can be suppressed even during overload operation or when auxiliary equipment is stopped.
It is possible to obtain a cooling system for a static induction device of this type that can extend the overload operation time.

[Brief description of the drawings]

FIG. 1 is a vertical sectional side view showing an embodiment of a cooling system for a stationary induction device according to the present invention.

FIG. 2 is a longitudinal sectional side view showing another embodiment of the cooling system for the stationary induction device of the present invention.

FIG. 3 is a longitudinal sectional side view showing another embodiment of the cooling system for the stationary induction device of the present invention.

[Explanation of symbols]

1 ... equipment room, 2 ... body tank, 3 ... gas-insulated transformer, 4
... lead duct, 5 ... blower, 6 ... gas-water heat exchanger,
7 ... piping, 8 ... cooling water piping, 9 ... pump, 10 ... cooling tower, 11 ... intake wind tunnel, 12 ... blower, 13 ... exhaust wind tunnel,
14: blower, 15: heat-insulating cover, 16: blower, 17
... air duct, 18 ... water-cooled pipe, 19 ... air-cooled cold water production equipment

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Hiroyuki Fujita 1-1-1, Kokubuncho, Hitachi City, Ibaraki Prefecture Inside the Kokubu Plant, Hitachi, Ltd. (72) Inventor Kiyoto Hiraishi 1-1-1, Kokubuncho, Hitachi City, Ibaraki Prefecture No. 1 Inside the Kokubu Plant of Hitachi, Ltd.

Claims (7)

[Claims] 1. A static induction device installed in an equipment room of an underground or indoor substation, and a first refrigerant filled in a main tank of the static induction device and directly cooling a winding and a core of the static induction device. A heat exchanger for cooling the first refrigerant with a second refrigerant; and a heat disposing means for disposing of the heat of the second refrigerant outdoors. A tank surface cooling means for cooling the surface of the main body tank of the stationary induction device, and a heat transfer means for transferring heat of the surface of the main body tank to the outside of the equipment room without dissipating heat into the room where the stationary induction device is installed. A cooling system for a stationary induction device. 2. A static induction device installed in an equipment room of an underground or indoor substation, and a first refrigerant filled in a main tank of the static induction device and directly cooling a winding and a core of the static induction device. A heat exchanger for cooling the first refrigerant with a second refrigerant; and a heat disposing means for disposing of the heat of the second refrigerant outdoors. A heat-insulating cover that covers at least a part of the main body tank of the stationary induction device, a blower that circulates cool air in an equipment room in which the static induction device is installed in a gap between the heat-insulating cover and the main body tank, A cooling system for a stationary induction appliance, comprising: a cooling air passage that guides cold air that has passed through the gap to the outside of the equipment room without discharging the cool air into the equipment room. 3. A static induction device installed in an equipment room of an underground or indoor substation, and a first refrigerant filled in a main tank of the static induction device and directly cooling a winding and an iron core of the static induction device. A heat exchanger that cools the first refrigerant with a second refrigerant; a heat disposal unit that disposes of the heat of the second refrigerant outdoors; In a cooling system for a stationary induction electric device having an exhaust wind tunnel for exhausting outdoors, a heat insulating cover that covers at least a part of a main body tank of the stationary induction electric appliance, A blower that circulates cool air in the equipment room in which the static induction device is installed in the gap, and a wind guide path that guides the cool air that has passed through the gap to the exhaust wind tunnel without discharging the cool air into the equipment room. To rest Conductive collector cooling system. 4. A stationary induction device installed in an equipment room of an underground or indoor substation, and a first refrigerant filled in a main tank of the stationary induction device and directly cooling a winding and an iron core of the static induction device And a heat exchanger for cooling the first refrigerant with a second refrigerant, and a cooling system for a stationary induction electric machine including a heat disposal means for disposing of the heat of the second refrigerant outdoors. And a tank surface water cooling means for cooling the surface of the main body tank of the stationary induction electric device, and a chilled water supply means for supplying cold water to the tank surface water cooling means. 5. A static induction device installed in an underground or indoor substation, a first refrigerant that directly cools a winding and an iron core of the static induction device, and the first refrigerant is cooled by a second refrigerant. A cooling system for a stationary induction device, comprising: a heat exchanger to be cooled; and a heat disposal means for disposing of the heat of the second refrigerant to the outside. Means, an air-cooled chilled water producing means for supplying chilled water to the tank surface water-cooling means, and a guide for discharging the air blown out from the air-cooled chilled water producing means to the outside without discharging the air into the equipment room in which the stationary induction device is installed. A cooling system for a stationary induction device, comprising a wind path. 6. A stationary induction device installed in an underground or indoor substation, a first refrigerant that directly cools a winding and an iron core of the stationary induction device, and a second refrigerant that cools the first refrigerant. In a cooling system for a stationary induction electric device including a heat exchanger and heat disposing means for disposing of the heat of the second refrigerant to the outside, a tank surface water cooling for cooling a main tank surface of the stationary induction electric device to the cooling system. Means and a refrigerant supply bypass path for supplying a refrigerant from a system path for supplying the second refrigerant to the tank surface water cooling means. 7. The cooling system according to claim 4, wherein said tank surface water cooling means is a water cooling jacket or a water cooling pipe.