Cooling device of load switch

Abstract

The utility model relates to a synchronous grid-connected system, and discloses a cooling device of a load switch, the load switch and a single-phase enclosed bus share an enclosed shell, a current-carrying component of the load switch is arranged on the bus and is accommodated in the shell, and the cooling device comprises a first air outlet pipe, a first air return pipe, a heat exchanger and a first circulating fan. The first air outlet pipe and the first air return pipe are connected with the interior of the shell. The heat exchanger comprises a first hot air inlet and a first cold air outlet, the first hot air inlet is connected with the first air outlet pipe, and the first cold air outlet is connected with the first air return pipe to form a cooling circulation loop. The first circulating fan is connected to the first air outlet pipe and the first hot air inlet, and / or connected to the first cold air outlet and the first air return pipe, and drives air to circularly flow in the cooling circulation loop. The cooling device is simple and stable in structure, and the reliability of the load switch under the rated current operation condition can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of synchronous grid-connected systems, in particular to a cooling device for a load switch. Background Art

[0002] The synchronous grid-connected system of a nuclear power plant consists of a generator output terminal cover, a phase-separated enclosed busbar, a load switch and an automatic synchronizer. The functions of each part are as follows: The generator output terminal cover is used to ensure the isolation between phases and to ensure that personnel do not come into contact with live conductors. It provides a channel for air cooling for the terminals and also acts as a shield to reduce the external electromagnetic field. The phase-separated enclosed busbar is used to transmit the power generated by the generator to the main transformer and the step-down transformer, and to supply power to the protection system, the automatic excitation regulation system and the voltage transformer of the synchronization device. The load switch is used to synchronize the generator with the system. When disconnected, the unit is allowed to supply power to the auxiliary equipment of the plant from the 400kV / 500kV main grid outside the plant through the main transformer and the step-down transformer. When the ultra-high voltage circuit breaker is disconnected, the generator is allowed to run directly with the plant power. The automatic synchronizer is used to automatically compare the voltage, frequency and phase of the generator and the grid before the generator is connected to the grid, and give a signal to close the load switch or ultra-high voltage circuit breaker when the requirements are met.

[0003] In order to meet the requirements of the 27200A rated current, the current-carrying parts of the load switch are cooled by the cooling air of the closed busbar through its shell in addition to water cooling. Usually, air inlets and outlets are set on the shell of the closed busbar so that air can enter and exit the shell, so it is necessary to constantly replace fresh external cold air to ensure the cooling effect. The load switch can carry 24kA only when it is water-cooled, 15kA only when it is air-cooled, and only 10kA when there is no water cooling or air cooling. Obviously, the rated current operation can only be met when both cooling methods are put into operation. When one of the cooling methods fails, the rated current operation cannot be guaranteed, and the reliability is low. In addition, the water cooling system has a complex structure, strict system operation parameters, and a high failure rate. Utility Model Content

[0004] The technical problem to be solved by the present invention is to provide a cooling device for a load switch in view of at least one defect of the related technology mentioned in the above background technology: the reliability of water cooling and external air cooling of the load switch is low.

[0005] The utility model solves the technical problem by adopting a technical solution: constructing a cooling device for a load switch, wherein the load switch and a single-phase enclosed busbar share a closed housing, the current-carrying component of the load switch is arranged on the busbar and accommodated in the housing, and the cooling device comprises:

[0006] a first air outlet duct and a first air return duct, wherein a first end of the first air outlet duct and a first end of the first air return duct are both connected to the interior of the housing;

[0007] a heat exchanger, the heat exchanger comprising a first hot air inlet and a first cold air outlet, the first hot air inlet being connected to the second end of the first air outlet duct, and the first cold air outlet being connected to the second end of the first return air duct, to form a cooling circulation loop;

[0008] A first circulation fan, wherein the first circulation fan is connected to the first air outlet duct and the first hot air inlet, and / or connected to the first cold air outlet and the first return air duct, drives air to circulate in the cooling circulation loop.

[0009] Preferably, in the cooling device of the load switch of the utility model, the heat exchanger further comprises a second hot air inlet and a second cold air outlet;

[0010] The cooling device also includes:

[0011] a second air outlet duct and a second air return duct, wherein the second hot air inlet is connected to the interior of the shell through the second air outlet duct, and the second cold air outlet is connected to the interior of the shell through the second air return duct, so as to form a cooling circulation loop;

[0012] a second circulation fan, the second circulation fan being connected to the second air outlet duct and the second hot air inlet, and / or connected to the second cold air outlet and the second return air duct;

[0013] A first switching component, the first switching component is disposed between the housing and the first air outlet pipe and the second air outlet pipe, and is used to switch the housing to be connected to the first air outlet pipe or the second air outlet pipe;

[0014] The second switching component is arranged between the shell and the first return air duct and the second return air duct, and is used for switching the shell to be connected with the first return air duct or the second return air duct.

[0015] Preferably, in the cooling device of the load switch described in the utility model, the first switching component and the second switching component are reversing valves.

[0016] Preferably, in the cooling device for the load switch described in the utility model, the first air outlet duct, the first air return duct, the second air outlet duct and the second air return duct are connected to the top of the shell.

[0017] Preferably, in the cooling device of the load switch described in the utility model, the cooling device further comprises:

[0018] A cooling air unit, wherein the air outlet of the cooling air unit is opposite to the heat exchanger and takes away the heat transferred to the heat exchanger.

[0019] Preferably, in the cooling device of the load switch described in the utility model, the cooling air group includes a main cooling air group and a backup cooling air group, the air outlet of the main cooling air group is opposite to the first area on one side of the heat exchanger, and the air outlet of the backup cooling air group is opposite to the second area on one side of the heat exchanger, and the first area and the second area are adjacent.

[0020] Preferably, in the cooling device of the load switch of the utility model, the main cooling air unit and the standby cooling air unit respectively include:

[0021] At least two cooling fans are provided, and at least two of the cooling fans are arranged along the direction from the hot air inlet to the cold air outlet of the heat exchanger.

[0022] Preferably, in the cooling device of the load switch described in the utility model, the cooling air unit is arranged on the top of the heat exchanger, and the air outlet of the cooling air unit faces downward.

[0023] Preferably, in the cooling device of the load switch described in the utility model, the cooling device further comprises:

[0024] A base, on which the load switch is arranged.

[0025] Preferably, in the cooling device of the load switch described in the utility model, the heat exchanger is a plate heat exchanger or a tube heat exchanger.

[0026] By implementing the utility model, the following beneficial effects are achieved:

[0027] The cooling device of the load switch of the utility model can form a cooling circulation loop, and the heat generated by the current-carrying components is transferred to the air inside the shell. The hot air exchanges heat and cools down when flowing through the heat exchanger through the cooling circulation loop, and then the cold air flows back to the inside of the shell to continue to take away the heat generated by the current-carrying components, thereby cooling the load switch. The cooling device has a simple and stable structure and can improve the reliability of the load switch under rated current operating conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0029] Figure 1 It is a front view of the cooling device of the load switch of the utility model;

[0030] Figure 2 It is a right view of the cooling device of the load switch of the utility model;

[0031] Figure 3 It is a top view of the cooling device of the load switch of the utility model. DETAILED DESCRIPTION

[0032] In order to have a clearer understanding of the technical features, purposes and effects of the present utility model, the specific implementation methods of the present utility model are now described in detail with reference to the accompanying drawings.

[0033] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0034] In the description of the utility model, it is necessary to understand that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the utility model. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the utility model, unless otherwise specified, "multiple" means two or more.

[0035] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "located at", and "located at" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or a chemical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood by specific circumstances.

[0036] The load switch 1 and the single-phase enclosed busbar 2 share a closed housing 11. The current-carrying components (not shown) of the load switch 1 are arranged on the busbar (not shown) and accommodated in the housing 11. During the operation of the current-carrying components, a certain amount of heat is generated due to the passage of current and is transferred to the air inside the housing 11. At this time, the current-carrying components need to be cooled. Figure 1 As shown, an embodiment of the utility model discloses a cooling device 3 for a load switch, including a first air outlet duct 31, a first air return duct 32, a heat exchanger 33 and a first circulation fan 34, which are specifically as follows:

[0037] The first end of the first air outlet duct 31 and the first end of the first air return duct 32 are both connected to the interior of the housing 11. Figure 3 As shown, the heat exchanger 33 includes a first hot air inlet 331 and a first cold air outlet 332. The first hot air inlet 331 is connected to the second end of the first air outlet duct 31, and the first cold air outlet 332 is connected to the second end of the first return air duct 32, forming a cooling circulation loop. The first circulation fan 34 is connected to the first air outlet duct 31 and the first hot air inlet 331, or connected to the first cold air outlet 332 and the first return air duct 32, driving the air to circulate in the cooling circulation loop. Preferably, in order to enhance the circulation flow, as Figure 1 and Figure 3 The shown one includes two first circulation fans 34, which are connected to the first air outlet 31 and the first hot air inlet 331, and connected to the first cold air outlet 332 and the first return air duct 32. The heat generated by the current-carrying components is exchanged in the heat exchanger 33 through the cooling circulation loop to complete the cooling of the current-carrying components. Specifically, the heat generated by the current-carrying components is transferred to the air inside the shell 11, and the hot air is cooled by heat exchange when flowing through the heat exchanger 33 through the cooling circulation loop. Then the cold air flows back to the shell 11 to continue to take away the heat generated by the current-carrying components, thereby cooling the current-carrying components. In addition, the heat generated by the busbar is also exchanged in the heat exchanger through the cooling circulation loop to complete the cooling of the busbar. It can be understood that the cooling transposition can cool the current-carrying components or the busbar, and can also cool the current-carrying components and the busbar at the same time.

[0038] In some embodiments, the heat exchanger 33 is a plate heat exchanger 33 or a tube heat exchanger 33. The plate heat exchanger 33 or the tube heat exchanger 33 is only an example and is not limited thereto. Other heat exchangers may also be used.

[0039] In order to ensure stable cooling, some embodiments also provide backup cooling, such as Figure 2 and Figure 3 As shown, the heat exchanger 33 further includes a second hot air inlet 333 and a second cold air outlet 334, and the cooling device 3 further includes a second air outlet duct 36, a second return air duct (not shown), a second circulation fan 37, a first switching component (not shown) and a second switching component (not shown), as follows:

[0040] The second hot air inlet 333 is connected to the inside of the housing 11 through the second air outlet 36, and the second cold air outlet 334 is connected to the inside of the housing 11 through the second return air duct, forming a cooling circulation loop. The second circulation fan 37 is connected to the second air outlet 36 and the second hot air inlet 333, or to the second cold air outlet 334 and the second return air duct. Preferably, in order to enhance the circulation flow, Figure 3The second circulation fan 37 is shown as including two second circulation fans 37, which are respectively connected to the second air outlet 36 and the second hot air inlet 333, and connected to the second cold air outlet 334 and the second return air duct. Since hot air goes upward, it is preferred that the first air outlet 31, the first return air duct 32, the second air outlet 36 and the second return air duct are connected to the top of the housing 11.

[0041] The first switching assembly is provided between the housing 11 and the first air outlet duct 31 and the second air outlet duct 36, and is used to switch the housing 11 to communicate with the first air outlet duct 31 or the second air outlet duct 36. The second switching assembly is provided between the housing 11 and the first return air duct 32 and the second return air duct, and is used to switch the housing 11 to communicate with the first return air duct 32 or the second return air duct. It can be understood that the first air outlet duct 31 can be communicated with the first return air duct 32 or the second return air duct, and the second air outlet duct 36 can be communicated with the first return air duct 32 or the second return air duct.

[0042] In some embodiments, the first switching component and the second switching component are reversing valves, such as three-way valves. The three-way valve is only an example and is not limited here. Other reversing valves may also be used.

[0043] In some embodiments, the first circulation fan 34 and the second circulation fan 37 are centrifugal circulation fans or axial circulation fans. Here, the centrifugal circulation fans or axial circulation fans are only examples and are not limited thereto. Other circulation fans may also be used.

[0044] In this embodiment, the cooling device 3 further includes a cooling air unit 35, the air outlet of the cooling air unit 35 is opposite to the heat exchanger 33, and takes away the heat transferred from the current-carrying components and / or the busbar to the heat exchanger 33. In some embodiments, the cooling air unit 35 is arranged on the top of the heat exchanger 33, and the air outlet of the cooling air unit 35 is downward and opposite to the heat exchanger 33.

[0045] In some embodiments, in order to ensure the stability of cooling, the cooling air unit 35 includes a main cooling air unit and a standby cooling air unit. The air outlet of the main cooling air unit is opposite to the first area on one side of the heat exchanger 33, and the air outlet of the standby cooling air unit is opposite to the second area on one side of the heat exchanger 33. The first area and the second area are adjacent. When the main cooling air unit fails, the standby cooling air unit can be used to cool the second area adjacent to the first area to minimize the impact of the failure, and preferably one side of the heat exchanger 33 is the top. Specifically, Figure 3As shown, the main cooling air unit includes at least two main cooling fans 351, and the at least two main cooling fans 351 are arranged in the direction from the first hot air inlet 331 to the first cold air outlet 332, and preferably, every two main cooling fans 351 are arranged diagonally. The standby cooling air unit includes at least two standby cooling fans 352, and at least two standby cooling fans 352 are arranged in the direction from the second hot air inlet 333 to the second cold air outlet 334, and preferably, every two standby cooling fans 352 are arranged diagonally. It can be understood that in some other embodiments, there can be at least three, four or any number of cooling fans, for example, the cooling fan is a fan, and the fan here is only an example and is not limited, and can also be other cooling fans.

[0046] In some embodiments, Figure 2 As shown, the cooling device 3 further includes a base 38 , and the shell 11 is disposed on the base 38 .

[0047] In a specific embodiment, each load switch and single-phase closed bus is equipped with a cooling device. The synchronous grid-connected system of the nuclear power plant has three load switches and three phases, each phase is a single-phase closed bus, and therefore is equipped with three cooling devices. Each cooling device 3 includes 6 cooling fans (3 main cooling fans 351 and 3 spare cooling fans 352), 2 first circulation fans 34, 2 second circulation fans 37 as spares, and 1 heat exchanger 33. During normal operation, the two first circulation fans 34 are operated to cause the air inside the housing 11 to form a closed cycle, and the three main cooling fans 351 are operated to cool the hot air inside the housing 11 through the heat exchanger 33. During normal operation, the air inside the housing 11 also serves as the operating air source of the load switch 1.

[0048] In some other embodiments, the heat exchanger 33 further includes a water circulation inlet (not shown) and a water circulation outlet (not shown) connected to the water circulation inlet, and the cooling device 1 further includes a water tank (not shown), which replaces the cooling air unit, and the water tank is connected to the water circulation inlet and the water circulation outlet respectively. The heat generated by the current-carrying components and / or the busbar is transferred to the air inside the shell 11, and the hot air exchanges heat and cools down with the water in the water tank when flowing through the heat exchanger 33 through the cooling circulation loop, and then the cold air flows back to the inside of the shell 11 to continue to take away the heat generated by the current-carrying components and / or the busbar, thereby cooling the current-carrying components and / or the busbar. Among them, the water tank also includes a water replenishment port (not shown) and a water outlet (not shown), so that the water tank has enough cold water to exchange heat with the hot air in the heat exchanger 33.

[0049] By implementing the utility model, the following beneficial effects are achieved:

[0050] The cooling device of the load switch of the utility model can form a cooling circulation loop, and the heat generated by the current-carrying components is transferred to the air inside the shell. The hot air exchanges heat and cools down when flowing through the heat exchanger through the cooling circulation loop, and then the cold air flows back to the inside of the shell to continue to take away the heat generated by the current-carrying components, thereby cooling the load switch. The cooling device has a simple and stable structure and can improve the reliability of the load switch under rated current operating conditions.

[0051] It can be understood that the above embodiments only express some implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the patent scope of the utility model; it should be pointed out that for ordinary technicians in this field, without departing from the concept of the utility model, the above embodiments or technical features can be freely combined, and several deformations and improvements can be made, which all belong to the protection scope of the utility model, that is, the embodiments described in "some embodiments" can be freely combined with any of the above and below embodiments; therefore, all equivalent changes and modifications made to the scope of the claims of the utility model should fall within the scope of the claims of the utility model.

Claims

1. A cooling device for a load switch, characterized in that: The load switch and the single-phase enclosed busbar share a closed housing, the current-carrying components of the load switch are arranged on the busbar and accommodated in the housing, and the cooling device comprises: a first air outlet duct and a first air return duct, wherein a first end of the first air outlet duct and a first end of the first air return duct are both connected to the interior of the housing; a heat exchanger, the heat exchanger comprising a first hot air inlet and a first cold air outlet, the first hot air inlet being connected to the second end of the first air outlet duct, and the first cold air outlet being connected to the second end of the first return air duct, to form a cooling circulation loop; A first circulation fan, wherein the first circulation fan is connected to the first air outlet duct and the first hot air inlet, and / or is connected to the first cold air outlet and the first return air duct, and drives the air to circulate in the cooling circulation loop.

2. The cooling device for load switch according to claim 1, characterized in that: The heat exchanger further comprises a second hot air inlet and a second cold air outlet; The cooling device also includes: a second air outlet duct and a second air return duct, wherein the second hot air inlet is connected to the interior of the shell through the second air outlet duct, and the second cold air outlet is connected to the interior of the shell through the second air return duct, so as to form a cooling circulation loop; a second circulation fan, the second circulation fan being connected to the second air outlet duct and the second hot air inlet, and / or connected to the second cold air outlet and the second return air duct; A first switching component, the first switching component is disposed between the housing and the first air outlet pipe and the second air outlet pipe, and is used to connect the housing with the first air outlet pipe or the second air outlet pipe; The second switching component is arranged between the shell and the first return air duct and the second return air duct, and is used to connect the shell with the first return air duct or the second return air duct.

3. The cooling device for load switch according to claim 2, characterized in that: The first switching component and the second switching component are reversing valves.

4. The cooling device for load switch according to claim 2, characterized in that: The first air outlet duct, the first air return duct, the second air outlet duct and the second air return duct are connected to the top of the shell.

5. The cooling device for load switch according to claim 1 or 2, characterized in that: The cooling device also includes: A cooling air unit, wherein the air outlet of the cooling air unit is opposite to the heat exchanger and takes away the heat transferred to the heat exchanger.

6. The cooling device for load switch according to claim 5, characterized in that: The cooling air unit includes a main cooling air unit and a backup cooling air unit. The air outlet of the main cooling air unit is opposite to the first area on one side of the heat exchanger, and the air outlet of the backup cooling air unit is opposite to the second area on one side of the heat exchanger. The first area and the second area are adjacent.

7. The cooling device for load switch according to claim 6, characterized in that: The main cooling air unit and the standby cooling air unit respectively include: At least two cooling fans are provided, and at least two cooling fans are arranged along the direction from the hot air inlet to the cold air outlet of the heat exchanger.

8. The cooling device for load switch according to claim 5, characterized in that: The cooling air unit is arranged on the top of the heat exchanger, and the air outlet of the cooling air unit faces downward.

9. The cooling device for load switch according to claim 1, characterized in that: The cooling device also includes: A base, on which the shell is arranged.

10. The cooling device for load switch according to claim 1, characterized in that: The heat exchanger is a plate heat exchanger or a tube heat exchanger.

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