A test device for simulating different grounding states of high voltage bushing end screen

Abstract

The invention discloses a test device for simulating different grounding states of a high-voltage bushing end screen, comprising a high-voltage bushing, a wall bushing, a linear displacement mechanism, a signal detector and an industrial control computer for control and display. The axis of the central conductor of the wall bushing and the lead-out conductor of the bushing end screen coincide. The industrial control computer for control and display controls the linear displacement mechanism to drive the movement of the wall bushing, thereby realizing the change of the distance between the central conductor of the wall bushing and the lead-out conductor of the high-voltage bushing end screen, so as to simulate different grounding states between the bushing end screen and the ground potential, namely, short circuit, virtual connection and open circuit states. The signal detector transmits the detected information to the industrial control computer for control and display for processing and analysis, thereby providing an effective test device for scientific research related to the high-voltage bushing end screen. It is applicable to the field of power transmission.

Description

Technical Field

[0001] The invention relates to the technical field of high voltage insulation, in particular to a test device for simulating different grounding states of a high voltage bushing end screen. Background Art

[0002] At present, high-voltage bushings are key equipment in power transmission projects and the "only way" for power transmission. They mainly play the role of current carrying, insulation and support. They are one of the equipment in the power system that is simultaneously subjected to the influence of electricity, heat, force and external insulation. The importance of their safe and reliable operation is self-evident. If an insulation failure occurs in the operating bushing, the bushing body may be damaged at the least, and the failure may cause the bushing to explode, causing serious damage to the transformer. The losses caused by reduced power transmission or line power outage are even greater, which seriously affects the safe and reliable operation of the power grid. In recent years, the failure rate of operating capacitor-type high-voltage bushings has been on the rise. The main causes of failure include: oil leakage, overheating of bushing joints and poor grounding of the bushing end screen. Faults such as oil leakage can be discovered through inspections and infrared temperature measurement, but poor grounding of the bushing end screen is difficult to be discovered in a timely and effective manner, which is extremely harmful to the operation of the transformer. According to incomplete statistics, failures caused by poor grounding of the bushing end screen account for 10% of the total number of bushing failures. Therefore, it is necessary to strengthen the monitoring of the operating status of the bushing end screen, conduct in-depth analysis and research on the impact of different grounding states of the high-voltage bushing end screen on the bushing voltage waveform, end screen leakage current, bushing main insulation, etc., promptly discover and solve the problem of poor grounding of the bushing end screen, and propose practical and effective operation and maintenance measures.

[0003] The grounding state of the high-voltage bushing end screen can be roughly divided into short circuit, virtual connection and open circuit. Among them, the poor grounding of the end screen is mainly because the bushing end screen is in a virtual connection and open circuit state, which leads to the electric field distortion of the core capacitance layer of the bushing and the continuous discharge of the end screen to the ground. Therefore, in order to study the influence of the grounding state of the high-voltage bushing end screen on the bushing, it is necessary to accurately simulate different grounding states, such as short circuit, virtual connection and open circuit, as well as control key parameters such as discharge amount and discharge number. At present, there is no corresponding test device at home and abroad, and it is impossible to simulate the different grounding states of the high-voltage bushing end screen. For this reason, this patent provides a test system for simulating different grounding states of the high-voltage bushing end screen. In the scientific research work related to the bushing end screen, the system can accurately simulate the short circuit, virtual connection and open circuit states of the bushing end screen. Summary of the invention

[0004] In view of the problems existing in the prior art, the purpose of the present invention is to provide a test device for simulating different grounding states of the high-voltage bushing end screen. The invention simulates different grounding states of the high-voltage bushing end screen by the distance between the bushing end screen lead-out conductor and the center conductor of the wall bushing, which facilitates the experimental personnel to conduct experimental research on different grounding states of the bushing end screen.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical scheme: comprising a high-voltage bushing, a wall bushing, a linear displacement mechanism, a signal detector and an industrial control computer for control and display, wherein a high-voltage bushing end screen is fixedly installed on the side wall of the high-voltage bushing, and a bushing end screen lead-out conductor is fixedly installed at the middle position of the high-voltage bushing end screen, and a wall bushing central conductor is fixedly installed on the axis of the wall bushing, the axis of the wall bushing central conductor coincides with the axis of the bushing end screen lead-out conductor, and a linear displacement mechanism is installed at the middle position of the wall bushing, the linear displacement mechanism comprises a slide rod and a base, the middle mounting flange on the wall bushing is mounted on the slide rod, and the bottom of the slide rod It is slidably installed on the upper surface of the base, so that the central conductor of the wall bushing moves linearly back and forth on the axis of the conductor lead-out from the end screen of the bushing. At the same time, one end of the central conductor of the wall bushing is electrically connected to the grounding wire, and the other end of the grounding wire is electrically connected to the grounding point, and a signal detector is fixedly installed in the middle position of the grounding wire. At the same time, the device is equipped with an industrial computer for control and display, which is fixedly installed on the operating desktop, and the industrial computer for control and display is electrically connected to the sliding rod of the linear displacement mechanism and the signal detector. The movement of the linear displacement mechanism can be directly controlled by the industrial computer for control and display, and the detection information from the signal detector can be displayed.

[0006] As a further solution of the present invention: the wall bushing is composed of three parts: a central conductor of the wall bushing, an insulating jacket, and a middle mounting flange.

[0007] As a further solution of the present invention: the left and right ends of the central conductor of the wall bushing are plated with an anti-oxidation layer, such as nickel plating.

[0008] As a further solution of the present invention: the grounding wire is a wire or cable with an insulating layer, and the cross-section of the grounding wire is greater than 8mm 2 .

[0009] As a further solution of the present invention: the signal detector is a non-contact signal detector.

[0010] As a further solution of the present invention: the voltage level of the wall bushing is preferably 10 kV and above.

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention is provided with a high-voltage bushing and a wall bushing, and the linear displacement mechanism is controlled by an industrial computer for control and display to drive the horizontal movement of the wall bushing, so as to realize the change of the distance between the central conductor of the wall bushing and the lead-out conductor of the end screen of the high-voltage bushing, so as to simulate different grounding states between the end screen of the bushing and the ground potential, namely, short circuit, virtual connection and open circuit states, thereby providing an effective test device for scientific research related to the end screen of the high-voltage bushing. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural schematic diagram of the present invention.

[0013] As shown in the figure: 1. high-voltage bushing, 2. wall bushing, 3. linear displacement mechanism, 4. grounding wire, 5. signal detector, 6. industrial computer for control and display, 7. grounding point, 8. high-voltage bushing end screen, 9. bushing end screen lead-out conductor, 10. wall bushing center conductor, 12. base, 13. slide rod, 14. anti-oxidation layer. DETAILED DESCRIPTION

[0014] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. 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.

[0015] See also Figure 1 In an embodiment of the present invention, a test device for simulating different grounding states of a high-voltage bushing end screen includes a high-voltage bushing 1, a wall bushing 2, a linear displacement mechanism 3, a signal detector 5, and an industrial control computer 6 for control and display, wherein a high-voltage bushing end screen 8 is fixedly installed on the side wall of the high-voltage bushing 1, and a bushing end screen lead-out conductor 9 is fixedly installed at the middle position of the high-voltage bushing end screen 8, and a wall bushing central conductor 10 is fixedly installed on the axis of the wall bushing 2, and a linear displacement mechanism 3 is fixedly installed at the middle position of the wall bushing 2, and the linear displacement mechanism 3 includes a slide bar 13 and a base 12, wherein the slide bar 13 passes through the middle position of the wall bushing 2, and the slide bar 13 and the wall bushing The sleeves 2 are fixedly connected together, and the bottom of the slide bar 13 is slidably installed on the upper surface of the base 12. At the same time, one end of the central conductor 10 of the wall sleeve is electrically connected to the grounding wire 4, and the other end of the grounding wire 4 is electrically connected to the grounding point 7, and a signal detector 5 is fixedly installed in the middle position of the grounding wire 4. At the same time, the device is equipped with an industrial computer 6 for control and display, which is fixedly installed on the operating desktop, and the industrial computer 6 for control and display is electrically connected to the slide bar 13 of the linear displacement mechanism 3 and the signal detector 4. The horizontal movement of the linear displacement mechanism 3 can be directly controlled by the industrial computer 6 for control and display, and the detection information from the signal detector 5 can be displayed.

[0016] The wall bushing 2 is composed of a wall bushing center conductor 10, an insulating jacket and a middle mounting flange. At the same time, the left and right ends of the wall bushing center conductor 10 are plated with an anti-oxidation layer 14, such as nickel plating, which effectively ensures the reliability of the experimental results. The grounding wire 4 is an insulating wire and cable with a cross-section greater than 8mm. 2The signal detector 5 is a non-contact signal detector for detecting leakage current and partial discharge signal of the end screen of the high-voltage bushing, and more intuitively detecting the grounding state of the device. According to a preferred embodiment of the present invention, the voltage level of the wall bushing 1 is preferably 10kV.

[0017] It should be noted that the working principle and installation method of the control and display industrial computer 6 are common knowledge to those skilled in the art and will not be elaborated herein.

[0018] According to the above preferred embodiment provided by the present invention, the experimenter first fixes the wall bushing 2 on the wall surface, and fixes the high-voltage bushing 1 in the working position, so that the axis of the bushing end screen lead-out conductor 9 and the axis of the wall bushing center conductor 10 are on the same horizontal plane, and one end of the grounding wire 4 is electrically connected to the wall bushing center conductor 10, and the other end is electrically connected to the grounding point 7. At the same time, the signal detector 5 and the industrial computer 6 for control and display are fixed, and voltage is applied to the high-voltage bushing 1 through the metal guide block 11, and the simulation experiment can be started. When the central conductor 10 of the wall bushing is in close contact with the high-voltage bushing end screen 8 and the lead-out conductor 9 of the bushing end screen, there is a short circuit state between the bushing end screen and the ground potential, that is, the grounding is good; when there is a small gap between the central conductor 10 of the wall bushing and the high-voltage bushing end screen lead-out conductor 9, the high-voltage bushing end screen lead-out conductor 9 will produce a continuous discharge phenomenon to the central conductor 10 of the wall bushing, and the bushing end screen and the ground potential are in a virtual connection state, that is, the grounding is poor; when the distance between the central conductor 10 of the wall bushing and the high-voltage bushing end screen lead-out conductor 9 continues to increase, and there is no discharge phenomenon between the high-voltage bushing end screen lead-out conductor 9 and the central conductor 10 of the wall bushing, there is an open circuit state between the bushing end screen and the ground potential, that is, the grounding is poor. Therefore, the present invention controls the distance between the central conductor of the wall bushing and the central conductor of the high-voltage bushing end shield outlet bushing, thereby ultimately achieving the purpose of controlling different grounding states of the bushing end shield.

[0019] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art may still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention, and the contents not described in detail in this specification shall belong to the prior art known to professional and technical personnel in the field.

Claims

1. A test device for simulating different grounding states of a high-voltage bushing end screen, comprising a high-voltage bushing (1), a wall bushing (2), a linear displacement mechanism (3), a signal detector (5) and an industrial computer (6) for control and display, characterized in that: A high-voltage bushing end screen (8) is fixedly installed on the side wall of the high-voltage bushing (1), and a bushing end screen lead-out conductor (9) is fixedly installed at the middle position of the high-voltage bushing end screen (8). At the same time, a wall bushing central conductor (10) is fixedly installed on the axis of the wall bushing (2), and the axis of the wall bushing central conductor (10) coincides with the axis of the bushing end screen lead-out conductor (9). A linear displacement mechanism (3) is installed at the middle position of the wall bushing (2), and the linear displacement mechanism (3) comprises a slide bar (13) and a base (12). The middle mounting flange on the wall bushing (2) is mounted on the slide bar (13), and the bottom of the slide bar (13) is slidably mounted on the slide bar (13). The upper surface of the base (12) enables the central conductor (10) of the wall bushing to move linearly forward and backward on the axis of the conductor (9) leading out of the bushing end screen. At the same time, one end of the central conductor (10) of the wall bushing is electrically connected to a grounding wire (4), and the other end of the grounding wire (4) is electrically connected to a grounding point (7). A signal detector (5) is fixedly installed at the middle position of the grounding wire (4). At the same time, the device is equipped with an industrial control computer (6) for control and display. The industrial control computer (6) for control and display is fixedly installed on the operating table, and the industrial control computer (6) for control and display and the slide bar (13) of the linear displacement mechanism (3) and the signal detector (4) are electrically connected together. The wall bushing (2) is composed of three parts: a wall bushing central conductor (10), an insulating jacket and a middle mounting flange; The left and right ends of the central conductor (10) of the wall bushing are plated with an anti-oxidation layer (14).

2. A test device for simulating different grounding states of a high-voltage bushing end shield according to claim 1, characterized in that: The grounding wire (4) is a wire or cable with an insulating layer, and the cross-section of the grounding wire (4) is greater than 8 mm. 2 .

3. A test device for simulating different grounding states of a high-voltage bushing end shield according to claim 1, characterized in that: The signal detector (5) is a non-contact signal detector.

4. A test device for simulating different grounding states of a high-voltage bushing end shield according to claim 1, characterized in that: The voltage level of the wall bushing (1) is 10 kV and above.

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