Oil-immersed distribution transformer with oil-immersed low-voltage circuit breaker

Abstract

The invention relates to an oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker. The oil-immersed distribution transformer comprises a transformer oil tank, a transformer body, a high-voltage elbow-shaped cable unit, a tap switch, an oil-immersed low-voltage circuit breaker unit and a waterproof low-voltage socket, a transformer tap switch cover for waterproof sealing is arranged on the outer side of the tap switch; the oil-immersed low-voltage circuit breaker unit is arranged in the transformer oil tank, and the operation surface of the oil-immersed low-voltage circuit breaker unit is positioned on the outer side of the transformer oil tank; for the low-voltage side of the transformer body, one end of a circuit breaker pile head of the oil-immersed low-voltage circuit breaker unit is connected with a low-voltage outgoing line of the transformer body through a low-voltage cable, and the other end of the circuit breaker pile head is connected with a waterproof low-voltage socket arranged on a transformer oil tank through a low-voltage cable; and for the high-voltage side of the transformer body, the transformer body is respectively connected with a high-voltage elbow-type cable unit and a tap switch which are arranged on the transformer oil tank. Compared with the prior art, the invention has the advantages of higher reliability, protection and isolation functions and the like.

Description

Technical Field

[0001] The invention relates to the field of oil-immersed distribution transformers, in particular to an oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker. Background Art

[0002] At present, distribution transformers or box-type substations are widely used in traditional power grids or new energy power grids in China. They generally use ordinary bushings for high voltage, which do not have waterproof functions, and the protection of the distribution transformer itself is limited.

[0003] Usually, transformer operation protection relies on external grid high and low voltage switches and pole fuses; in case of lightning, it is protected by high voltage arresters. The low voltage load side is mainly protected by air circuit breakers during operation. In bad weather, the electrical equipment of the operation department cannot operate safely, which also affects the emergency handling ability. In some areas, electrical equipment is often unable to form rapid power transmission due to the influence of water; at the same time, outdoor operation is easily affected by the external environment. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a safe, reliable, and overall protective oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] An oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker comprises: a transformer oil tank, a transformer body, a high-voltage elbow-type cable unit, a tapping switch, an oil-immersed low-voltage circuit breaker unit and a waterproof low-voltage socket;

[0007] The transformer body is installed in the transformer oil tank;

[0008] For the high-voltage side of the transformer body, the transformer body is respectively connected to a high-voltage elbow cable unit and a tap changer installed on the transformer oil tank;

[0009] A transformer tap changer cover for waterproof sealing is provided on the outside of the tap changer;

[0010] The oil-immersed low-voltage circuit breaker unit is arranged in the transformer oil tank, and the operating surface of the oil-immersed low-voltage circuit breaker unit is located outside the transformer oil tank;

[0011] For the low-voltage side of the transformer body, one end of the circuit breaker post of the oil-immersed low-voltage circuit breaker unit is connected to the low-voltage outgoing line of the transformer body through a low-voltage cable, and the other end is connected to a waterproof low-voltage socket arranged on the transformer oil tank through a low-voltage cable. The waterproof low-voltage socket is used to connect to the emergency power supply.

[0012] Furthermore, the oil-immersed low-voltage circuit breaker unit includes an oil-immersed low-voltage circuit breaker and an oil-immersed circuit breaker oil chamber, the oil-immersed low-voltage circuit breaker is installed in the oil-immersed circuit breaker oil chamber and is located inside the transformer oil tank, and the operating surface of the oil-immersed low-voltage circuit breaker is located outside the transformer oil tank.

[0013] Furthermore, an oil-immersed circuit breaker waterproof cover for waterproof sealing is also provided on the outer side of the operating surface of the oil-immersed low-voltage circuit breaker.

[0014] Furthermore, the oil chamber of the oil-immersed circuit breaker is connected to an external oil passage.

[0015] Furthermore, the oil-immersed low-voltage circuit breaker unit and the waterproof low-voltage socket are connected by welding at a connection inside the transformer oil tank.

[0016] Furthermore, the waterproof low-voltage socket is provided with a threaded opening for sealingly connecting a low-voltage cable of an emergency power supply.

[0017] Furthermore, a cable fixing bracket is provided on the transformer oil tank for supporting the low-voltage cable connected to the waterproof low-voltage socket.

[0018] Furthermore, the transformer oil tank is a steel plate or a stainless steel plate with a thickness of not less than 4 mm.

[0019] Furthermore, the high-voltage elbow cable unit includes a high-voltage elbow cable head, a bushing base and a bushing fixing device, the bushing base is fixed on the transformer oil tank through the bushing fixing device, and the bushing base is electrically connected to the high-voltage elbow cable head and the transformer body respectively.

[0020] Furthermore, the coil of the transformer body adopts enameled wire of Class B or above, the insulating material adopts insulating material of Class B or above, and the high flash point oil in the transformer oil tank meets the K-class fire protection requirements.

[0021] Compared with the prior art, the present invention has the following advantages:

[0022] (1) The oil-immersed distribution transformer provided by the present invention has an independent oil-immersed low-voltage breaker chamber inside, which can ensure that the transformer is protected from external impact. At the same time, it is disconnected from the transformer body in harsh environments or special working conditions to ensure the access of low-voltage emergency power supply. The low voltage adopts a waterproof low-voltage socket to meet the safe operation of the transformer under various working conditions, making the transformer more reliable and able to play a protection and isolation function.

[0023] (2) The present invention implements a variety of waterproofing arrangements for the oil-immersed distribution transformer, such as a fully sealed transformer oil tank, a transformer tap changer cover provided on the outside of the tap changer, and an oil-immersed circuit breaker waterproof cover provided on the outside of the operating surface of the oil-immersed low-voltage circuit breaker. The overall protection capability reaches IP66 or above, and the transformer can operate under harsh working conditions, thereby improving power supply reliability.

[0024] (3) The oil-immersed distribution transformer of the present invention is provided with a high-voltage elbow-type cable unit, which can achieve a more reliable and rapid connection with a traditional power grid through a high-voltage elbow-type cable head. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the internal side of an oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker provided in an embodiment of the present invention;

[0026] Figure 2 It is a schematic diagram of the internal main structure of an oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker provided in an embodiment of the present invention;

[0027] Figure 3 A front view of the structure of a three-phase oil-immersed low-voltage circuit breaker of an oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker provided in an embodiment of the present invention;

[0028] Figure 4 A side view of a three-phase oil-immersed low-voltage circuit breaker structure of an oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker provided in an embodiment of the present invention;

[0029] Figure 5 A front view of a waterproof low-voltage socket structure of an oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker provided in an embodiment of the present invention;

[0030] Figure 6 A side view of a waterproof low-voltage socket structure of an oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker provided in an embodiment of the present invention;

[0031] Figure 7 A schematic diagram of the transformer body structure of an oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker provided in an embodiment of the present invention;

[0032] In the figure, 1 is the transformer tap changer cover, 2 is the high-voltage elbow-type cable unit, 3 is the transformer oil tank, 4 is the oil-immersed low-voltage circuit breaker, 5 is the waterproof low-voltage socket, 6 is the oil chamber of the oil-immersed circuit breaker, 7 is the waterproof cover of the oil-immersed circuit breaker, 8 is the transformer high-ignition-point oil, and 9 is the transformer body. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0036] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the inventive product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0037] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0038] In addition, the terms "horizontal", "vertical" and the like do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0039] Example 1

[0040] like Figure 1 and Figure 2As shown, this embodiment provides an oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker, comprising: a transformer oil tank 3, a transformer body 9, a high-voltage elbow cable unit 2, a tap switch, an oil-immersed low-voltage circuit breaker unit and a waterproof low-voltage socket 5;

[0041] The transformer body 9 is installed in the transformer oil tank 3, and the transformer oil tank 3 is filled with transformer high ignition point oil 8;

[0042] For the high-voltage side of the transformer body 9, the transformer body 9 is respectively connected to the high-voltage elbow cable unit 2 and the tap changer installed on the transformer oil tank 3;

[0043] A transformer tap changer cover 1 for waterproof sealing is provided on the outside of the tap changer;

[0044] The oil-immersed low-voltage circuit breaker unit is arranged in the transformer oil tank 3, and the operating surface of the oil-immersed low-voltage circuit breaker unit is located outside the transformer oil tank 3; for the low-voltage side of the transformer body 9, one end of the circuit breaker pile head of the oil-immersed low-voltage circuit breaker unit is connected to the low-voltage outlet line of the transformer body 9 through a low-voltage cable, and the other end is connected to the waterproof low-voltage socket 5 arranged on the transformer oil tank 3 through a low-voltage cable. The waterproof low-voltage socket 5 is used to connect to the emergency power supply.

[0045] Specifically, the oil-immersed low-voltage circuit breaker unit includes an oil-immersed low-voltage circuit breaker 4 and an oil-immersed circuit breaker oil chamber 6. The oil-immersed low-voltage circuit breaker 4 is installed in the oil-immersed circuit breaker oil chamber 6 and is located inside the transformer oil tank 3. The operating surface of the oil-immersed low-voltage circuit breaker 4 is located outside the transformer oil tank 3.

[0046] Equivalent to, Figure 3 and Figure 4 As shown, an oil-immersed low-voltage circuit breaker 4 is added inside the transformer oil tank, and an independent oil-immersed circuit breaker oil chamber 6 is added outside the oil-immersed circuit breaker, wherein one end of the circuit breaker pile head is connected to the low-voltage outlet line of the transformer body 9 through a low-voltage cable, and the other end is connected to the low-voltage waterproof interface 5 through a low-voltage cable. When the transformer is running, if the low-voltage load is overloaded or fails, the oil-immersed low-voltage breaker 4 will be disconnected; and the emergency power supply can be connected through the waterproof low-voltage socket 5.

[0047] The connection between the oil-immersed low-voltage circuit breaker unit and the waterproof low-voltage socket 5 inside the transformer oil tank 3 is welded.

[0048] The oil chamber of the oil-immersed circuit breaker is an independent structure so the oil in the circuit breaker switch room will not pollute the transformer oil. At the same time, preferably, the oil chamber 6 of the oil-immersed circuit breaker is connected to an external oil port to ensure that the oil in the circuit breaker room can be replaced regularly and monitored regularly.

[0049] Preferably, an oil-immersed circuit breaker waterproof cover 7 for waterproof sealing is further provided on the outer side of the operating surface of the oil-immersed low-voltage circuit breaker 4 to achieve waterproof sealing of the oil-immersed low-voltage circuit breaker 4 .

[0050] Preferably, the oil-immersed low-voltage circuit breaker 4 is provided with a remote control module to implement remote control.

[0051] Preferably, in order to make the product more miniaturized and improve the reliability of product operation, the transformer oil tank 3 is designed with thick steel plate or stainless steel, with a thickness of not less than 4mm, and the heat dissipation method of the radiator is eliminated. The interior is filled with high-fuel oil, which can meet the K-level fire protection requirements and make the product more widely used.

[0052] Preferably, Figure 5 and Figure 6 As shown, the waterproof low-voltage socket 5 is provided with a threaded screw joint for sealing the low-voltage cable of the emergency power supply, that is, the external low-voltage cable is connected to the low-voltage cable waterproof interface 5 by a threaded screw joint for connection and sealing.

[0053] The transformer oil tank 3 is also provided with a cable fixing bracket for supporting the low-voltage cable connected to the waterproof low-voltage socket 5 to prevent the low-voltage cable from being stressed at the low-voltage cable waterproof interface, so that the low voltage can be output normally in the case of water immersion.

[0054] The high-voltage elbow cable unit 2 includes a high-voltage elbow cable head, a bushing base and a bushing fixing device. The bushing base is fixed on the transformer oil tank 3 through the bushing fixing device. The bushing base is electrically connected to the high-voltage elbow cable head and the transformer body 9 respectively.

[0055] Preferably, a lightning arrester may be provided at the high-voltage elbow cable head and equipped with a partial discharge device to enable remote monitoring of the operating status.

[0056] The high voltage elbow cable head can also be equipped with a protective fuse inside to protect the high voltage side. It is also an independent oil chamber that can be replaced.

[0057] Example 2

[0058] This embodiment is substantially the same as Embodiment 1, except that Figure 7 As shown, the insulation and heat-resistant design grade of the transformer body 9 is above Class B. Its coil adopts Class B or above enameled wire, and the insulation material is also above Class B. This makes the product have a higher overload capacity. At the same time, the product can be directly connected to the load because of the low voltage oil-immersed circuit breaker. This makes the product more widely used and more reliable.

[0059] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. An oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker, characterized in that: include: Transformer oil tank (3), transformer body (9), high-voltage elbow cable unit (2), tap changer, oil-immersed low-voltage circuit breaker unit and waterproof low-voltage socket (5); The transformer body (9) is installed in the transformer oil tank (3); For the high-voltage side of the transformer body (9), the transformer body (9) is respectively connected to a high-voltage elbow-type cable unit (2) and a tap switch installed on the transformer oil tank (3); A transformer tap changer cover (1) for waterproof sealing is provided on the outer side of the tap changer; The oil-immersed low-voltage circuit breaker unit is arranged in the transformer oil tank (3), and the operating surface of the oil-immersed low-voltage circuit breaker unit is located outside the transformer oil tank (3); For the low-voltage side of the transformer body (9), one end of the circuit breaker post of the oil-immersed low-voltage circuit breaker unit is connected to the low-voltage outlet line of the transformer body (9) via a low-voltage cable, and the other end is connected to a waterproof low-voltage socket (5) arranged on the transformer oil tank (3) via a low-voltage cable, and the waterproof low-voltage socket (5) is used to connect to an emergency power supply.

2. The oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker according to claim 1, characterized in that: The oil-immersed low-voltage circuit breaker unit comprises an oil-immersed low-voltage circuit breaker (4) and an oil-immersed circuit breaker oil chamber (6); the oil-immersed low-voltage circuit breaker (4) is installed in the oil-immersed circuit breaker oil chamber (6) and is located inside a transformer oil tank (3); and an operating surface of the oil-immersed low-voltage circuit breaker (4) is located outside the transformer oil tank (3).

3. The oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker according to claim 2, characterized in that: An oil-immersed circuit breaker waterproof cover (7) for waterproof sealing is also provided on the outside of the operating surface of the oil-immersed low-voltage circuit breaker (4).

4. The oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker according to claim 2, characterized in that: The oil chamber (6) of the oil-immersed circuit breaker is connected to an external oil passage.

5. The oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker according to claim 1, characterized in that: The connection between the oil-immersed low-voltage circuit breaker unit and the waterproof low-voltage socket (5) inside the transformer oil tank (3) is welded.

6. The oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker according to claim 5, characterized in that: The waterproof low-voltage socket (5) is provided with a threaded opening for sealingly connecting a low-voltage cable of an emergency power supply.

7. The oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker according to claim 6, characterized in that: The transformer oil tank (3) is also provided with a cable fixing bracket for supporting a low-voltage cable connected to the waterproof low-voltage socket (5).

8. The oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker according to claim 1, characterized in that: The transformer oil tank (3) is a steel plate or a stainless steel plate with a thickness of not less than 4 mm.

9. The oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker according to claim 1, characterized in that: The high-voltage elbow cable unit (2) comprises a high-voltage elbow cable head, a bushing base and a bushing fixing device, wherein the bushing base is fixed on a transformer oil tank (3) via the bushing fixing device, and the bushing base is electrically connected to the high-voltage elbow cable head and a transformer body (9) respectively.

10. The oil-immersed distribution transformer with an oil-immersed low-voltage circuit breaker according to claim 1, characterized in that: The coil of the transformer body (9) adopts enameled wire of Class B or above, the insulating material adopts insulating material of Class B or above, and the high-ignition-point oil in the transformer oil tank (3) meets the fire protection requirements of Class K.

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