Novel oil-immersed hollow neutral point grounding reactor

Abstract

The utility model discloses a novel oil-immersed hollow neutral point grounding reactor, which belongs to the technical field of power grid operation equipment, and comprises an oil tank and a reactor body, the reactor body is arranged in the oil tank, and the reactor body comprises an upper pressing frame, a lead, a coil, an end insulator, a magnetic shield, a lower foot pad and a tensioning screw; the magnetic shield comprises an upper magnetic shield and a lower magnetic shield. The end insulation comprises an upper end insulation and a lower end insulation. The transformer body fastens the upper magnetic shield, the upper end insulator, the coil, the lower end insulator, the lower magnetic shield and the lower foot pad into a whole through the tensioning screw, and the transformer body is positioned and fixed with the oil tank through the lower foot pad. The magnetic flux leakage prevention device is simple in structure, ingenious in design, capable of avoiding equipment faults caused by circulating current caused by local magnetic flux leakage, high in economical efficiency and stability and safe and reliable in operation.

Description

TECHNICAL FIELD

[0001] The utility model relates to a kind of power grid operation equipment technical field, specifically related to a kind of novel oil-immersed hollow neutral grounding reactor. BACKGROUND

[0002] With the development of power grid, autotransformer is widely used as high-voltage and super-high-voltage main transformer. Since the three-phase connection of autotransformer is in star structure, due to its structural characteristics, the medium voltage side of autotransformer has zero or close to zero reactance value, which causes the single-phase short-circuit current of system bus to be greater than the three-phase short-circuit current. By increasing small reactance grounding at the neutral point side of main transformer, that is, neutral grounding reactor, this method effectively reduces the single-phase short-circuit current of bus, limits the short-circuit current of bus; this method is not limited by power grid conditions, easy to promote, small investment and simple construction. High-voltage shunt reactor adopts star connection method, and single-phase grounding fault may occur in three-phase reactor during operation. At this time, grounding current will appear at the neutral point of reactor. At this time, if neutral grounding reactor is installed between the neutral point of reactor and ground, it can compensate line-to-line and ground capacitance, increase ground impedance and eliminate potential supply current, which plays a good protective role for reactor and line equipment.

[0003] However, the current neutral grounding reactor generally adopts dry-type hollow structure, which needs to be supported by reactor support insulator, causing large internal leakage magnetic field of the body. UTILITY MODEL CONTENT

[0004] To solve the problems in the prior art, the utility model provides an oil-immersed hollow neutral grounding reactor which can eliminate internal leakage magnetic field of the product, is connected between the neutral point of system and ground, and is used for limiting grounding current during system fault.

[0005] The utility model adopts the following technical solutions.

[0006] A novel oil-immersed hollow neutral grounding reactor comprises an oil tank and a body, the body is arranged in the oil tank, and the body comprises an upper pressing frame, a lead wire, a coil, an end insulation, a magnetic shield, a lower pad and a tensioning screw.

[0007] The magnetic shield comprises an upper magnetic shield and a lower magnetic shield, and the end insulation comprises an upper end insulation and a lower end insulation.

[0008] The body is fastened to an integral whole with the upper magnetic shield, the upper end insulation, the coil, the lower end insulation, the lower magnetic shield and the lower pad through the tensioning screw, and the body is positioned and fixed with the oil tank through the lower pad.

[0009] Preferably, the upper magnetic shield comprises a silicon steel sheet, an upper clamp and an insulating piece, the upper magnetic shield is stacked with the silicon steel sheet, and the upper clamp, the insulating piece and the silicon steel sheet are fastened to an integral whole through a screw.

[0010] Preferably, the lower magnetic shield comprises silicon steel sheets, lower clamps and insulating pieces, the lower magnetic shield is first stacked by the silicon steel sheets, and the lower clamps, the insulating pieces and the silicon steel sheets are fastened into a whole by the screw rod.

[0011] Preferably, the coil comprises a left half-column coil and a right half-column coil, the single coil is a continuous end-out wire structure, the first end is at the upper wire outlet, and the last end is at the lower wire outlet; the two coils are connected by the lower wire outlets, and the two coils form a series loop in electricity.

[0012] Preferably, the novel oil-immersed hollow neutral grounding reactor further comprises external components, the external components comprise an oil storage cabinet, a connecting pipeline between an oil tank and the oil storage cabinet, an external sleeve, a radiator, an oil level gauge, an oil surface temperature meter, a terminal box and a pressure release valve.

[0013] The oil tank, the oil storage cabinet and the connecting pipeline form a sealing system, and the sealing system is filled with transformer oil.

[0014] Preferably, the oil storage cabinet and the oil tank are connected by a pipeline and display the oil level in the oil storage cabinet by the oil level gauge.

[0015] Preferably, the body lead is led out through the external sleeve and connected to the neutral point of the system; and the radiator of the external component for cooling is arranged on the oil tank.

[0016] Preferably, the oil surface temperature meter of the external component for correctly displaying the oil surface temperature is arranged on the oil tank.

[0017] Preferably, the terminal box of the external component is arranged on the oil tank, converts signals during the operation of the reactor into electric signals and uploads the electric signals to a system comprehensive automation platform.

[0018] Preferably, the pressure release valve of the external component for preventing abnormal operation of the reactor is arranged on the oil tank.

[0019] Compared with the prior art, the novel oil-immersed hollow neutral grounding reactor has at least the following beneficial effects:

[0020] The novel oil-immersed hollow neutral grounding reactor has the advantages of simple structure, ingenious design, small magnetic leakage, small loss, low temperature rise, small noise, good linearity, avoidance of circulating current caused by local magnetic leakage and equipment failure, high economy and stability, safe and reliable operation, and the like. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a schematic diagram of an internal structure of the novel oil-immersed hollow neutral grounding reactor;

[0022] Figure 2 is an external front view of the novel oil-immersed hollow neutral grounding reactor;

[0023] Figure 3 is the external side view of the utility model;

[0024] Figure 4 is the external plan view of the utility model;

[0025] 1, oil tank, 2, upper pressure frame, 3, upper clamping piece, 4, upper magnetic shield, 5, upper end insulation, 6, tensioning screw, 7, lead, 8, right column coil, 9, lower end insulation, 10, lower clamping piece, 11, lower magnetic shield, 12, lower foot pad, 13, inter-coil lead, 14, left column coil, 15, oil storage tank, 16, oil tank and oil storage tank communication pipeline, 17, external sleeve, 18, radiator, 19, oil level gauge, 20, oil surface temperature gauge, 21, terminal box, 22, pressure relief valve. DETAILED DESCRIPTION

[0026] In order to make the utility model purposes, technical schemes and advantages more clearly, below will combine the drawings in the utility model embodiment, the technical scheme of the utility model is clearly and completely described.The embodiments described in the present application are only a part of the embodiments of the utility model, not all embodiments.Based on the spirit of the utility model, all other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of the utility model.

[0027] As Figure 1 Indicated, a new type of oil-immersed hollow neutral point grounding reactor, including oil tank 1 and the body in the oil tank;

[0028] The body includes upper pressure frame 2, lead 7, coil, end insulation, magnetic shield, lower foot pad 12 and tensioning screw 6;

[0029] The coil includes left half column coil 14 and right half column coil 8;End insulation includes upper end insulation 5 and lower end insulation 9;The magnetic shield includes upper magnetic shield 4 and lower magnetic shield 11.

[0030] The body is fixed as a whole by tensioning screw 6, upper magnetic shield 4, upper end insulation 5, coil, lower end insulation 9, lower magnetic shield 11 and lower foot pad 12, and the body is positioned and fixed with oil tank 1 by lower foot pad 12.

[0031] The upper magnetic shield 4 is composed of silicon steel sheet, upper clamping piece 3 and insulation, and the upper magnetic shield 4 is first stacked by silicon steel sheet, and the upper clamping piece 3, insulation and silicon steel sheet are fastened as a whole by screw;The lower magnetic shield is composed of silicon steel sheet, lower clamping piece 10 and insulation, and the lower magnetic shield is first stacked by silicon steel sheet, and the lower clamping piece 10, insulation and silicon steel sheet are fastened as a whole by screw;

[0032] The magnetic flux generated by the operation of the hollow coil passes through the left half-column coil 14, the lower magnetic shield 11, the right half-column coil 8 and the upper magnetic shield 4 in sequence, forming a complete magnetic circuit. Moreover, due to the provision of the upper magnetic shield 4 and the lower magnetic shield 11, most of the magnetic flux flows within the coil and the magnetic shield, greatly reducing the leakage magnetic flux of the hollow coil.

[0033] The coils are continuous, with the coil ends connected to the sleeve 17 via inter-coil leads 13 and leading outward. A single coil has a continuous end-out structure, with the first end exiting at the top and the last at the bottom. The two coils are connected by the lower leads, electrically forming a series circuit, thus achieving continuous magnetic flux flow.

[0034] The first end bushing is connected to the neutral point of the system through a connection line, and the end bushing is connected to the ground grid through relevant connection lines according to user needs. The coil also has internal support bars and high-strength insulation cylinders to support the structure of the coil.

[0035] like Figures 2-4 As shown, the novel oil-immersed hollow neutral-point grounding reactor further includes external components, which include an oil conservator 15, a connecting pipe 16 between the oil tank and the oil conservator, an external casing 17, a radiator 18, an oil level gauge 19, an oil level temperature gauge 20, a terminal box 21 and a pressure relief valve 22.

[0036] The oil tank 1, the oil storage cabinet 15 and the connecting pipe 16 together form a sealing system, which is filled with transformer oil and plays a role in isolating the air, preventing moisture in the air from entering the reactor and preventing the transformer oil from oxidizing.

[0037] The oil conservator 15 is connected to the oil tank 1 through a pipeline 16 to ensure that the volume of the insulating oil in the oil tank changes with temperature, and the oil level in the oil conservator is displayed by an oil level gauge 19. The oil conservator plays a role in compensating breathing, ensuring the constant pressure of the internal transformer oil and providing guarantee for product operation.

[0038] The body lead 7 is led out through the external sleeve 17, connected to the neutral point of the system, and flows through the neutral point grounding current.

[0039] The external component radiator 18 is arranged on the oil tank 1, and the heat generated by the reactor during operation is cooled and dissipated through the radiator 18 to achieve a thermal equilibrium state.

[0040] The external component oil level temperature gauge 20 is provided on the oil tank 1 and functions to correctly display the oil level temperature when the reactor is running, thereby providing a guarantee for the safe operation of the product.

[0041] The external component terminal box 21 is set on the oil tank 1, and converts signals such as the oil surface temperature, operating oil level, and internal pressure of the oil tank during operation of the reactor into electrical signals and uploads them to the system integrated automation platform, so that the user can monitor the operating status of the reactor in the control room.

[0042] The external component pressure relief valve 22 is provided on the oil tank 1 and is a protective device to prevent the internal pressure of the oil tank from being excessively high due to abnormal operation of the reactor.

[0043] Compared with the prior art, the beneficial effects of the present invention include at least:

[0044] The utility model has a simple structure and ingenious design, and has the excellent characteristics of small magnetic leakage, small loss, low temperature rise, low noise and good linearity. It can avoid equipment failure caused by circulating current caused by local magnetic leakage, has high economy and stability, and is safe and reliable in operation.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents, and any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. A novel oil-immersed hollow neutral-point grounding reactor, comprising an oil tank (1) and a reactor body, characterized in that: The device body is installed inside the oil tank (1), and comprises an upper pressing frame (2), a lead wire (7), a coil, end insulation, a magnetic shield, a lower pad (12) and a tensioning screw (6); The magnetic shield includes an upper magnetic shield (4) and a lower magnetic shield (11), and the end insulation includes an upper end insulation (5) and a lower end insulation (9); The device body is fastened into a whole by means of a tightening screw (6), the upper magnetic shield (4), the upper end insulation (5), the coil, the lower end insulation (9), the lower magnetic shield (11) and the lower pad (12), and the device body is positioned and fixed to the oil tank (1) via the lower pad (12).

2. The novel oil-immersed hollow neutral-point grounding reactor according to claim 1 is characterized in that: The upper magnetic shield (4) comprises silicon steel sheets, an upper clamp (3) and an insulating member. The upper magnetic shield (4) is stacked by the silicon steel sheets, and the upper clamp (3), the insulating member and the silicon steel sheets are fastened into a whole by screws.

3. The novel oil-immersed hollow neutral-point grounding reactor according to claim 1 is characterized in that: The lower magnetic shield (11) comprises silicon steel sheets, a lower clamp (10) and an insulating member. The lower magnetic shield (11) is first stacked by the silicon steel sheets, and the lower clamp (10), the insulating member and the silicon steel sheets are fastened into a whole by screws.

4. The novel oil-immersed hollow neutral-point grounding reactor according to claim 1 is characterized in that: The coil comprises a left semi-column coil (14) and a right semi-column coil (8), and a single coil is a continuous end-outlet structure, with the first end outlet at the upper part and the end outlet at the lower part; the two coils are connected by the lower outlet wires, and the two coils electrically form a series circuit.

5. The novel oil-immersed hollow neutral-point grounding reactor according to claim 1 is characterized in that: The novel oil-immersed hollow neutral-point grounding reactor further includes external components, which include an oil conservator (15), a connecting pipe (16) between the oil tank and the oil conservator, an external casing (17), a radiator (18), an oil level gauge (19), an oil level temperature gauge (20), a terminal box (21), and a pressure relief valve (22); The oil tank (1), the oil storage cabinet (15) and the connecting pipe (16) form a sealed system, and the interior is filled with transformer oil.

6. The novel oil-immersed hollow neutral-point grounding reactor according to claim 5 is characterized in that: The oil conservator (15) is connected to the oil tank (1) via a pipeline (16), and the oil level in the oil conservator is displayed via an oil level gauge (19).

7. The novel oil-immersed hollow neutral-point grounding reactor according to claim 5 is characterized in that: The body lead (7) is led out through an external sleeve (17) and connected to the neutral point of the system; the external component radiator (18) for cooling and heat dissipation is arranged on the oil tank (1).

8. The novel oil-immersed hollow neutral-point grounding reactor according to claim 5 is characterized in that: The external component oil level temperature gauge (20) for correctly displaying the oil level temperature is arranged on the oil tank (1).

9. The novel oil-immersed hollow neutral-point grounding reactor according to claim 5 is characterized in that: The external component terminal box (21) is arranged on the oil tank (1) and converts the signal generated when the reactor is running into an electrical signal and uploads it to the system integrated automation platform.

10. The novel oil-immersed hollow neutral-point grounding reactor according to claim 5, characterized in that: The external component pressure relief valve (22) for preventing abnormal operation of the reactor is arranged on the oil tank (1).

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