High-voltage direct-current GIL three-post insulator surface charge measuring device

Abstract

The utility model belongs to the technical field of surface charge measurement, and particularly relates to a high-voltage direct-current GIL three-post insulator surface charge measuring device, which is provided with an experimental chamber, a high-voltage guide rod is arranged in the experimental chamber, a central guide rod is sleeved on the high-voltage guide rod, the central guide rod penetrates through a three-post insulator, and an electric slide rail is arranged at the bottom of the experimental chamber. A charge measuring device is slidably mounted above the electric slide rail, the charge measuring device comprises a capacitance probe and a capacitance probe control device, the capacitance probe control device controls the capacitance probe to be perpendicular to the surface of the three-post insulator, and the capacitance probe is connected with a data acquisition device; according to the utility model, the surface charges of the front and back surfaces of the three-post insulator sample piece can be measured, the problem that most experimental devices can only measure the surface charges of the single surface of the three-post insulator in a single experiment at the present stage is solved, errors of measurement results caused by two experiments can be avoided, the experimental time is greatly shortened, and the experimental efficiency is improved. Experimental gas is greatly reduced, and the device is more economical.

Description

Technical Field

[0001] The utility model belongs to the technical field of surface charge measurement, and in particular relates to a surface charge measuring device for a high-voltage direct current GIL three-pillar insulator. Background Art

[0002] Gas Insulated Metal Enclosed Transmission Line (GIL) is composed of metal casing, tubular conductor and insulator. It is a kind of power transmission equipment that uses insulating gas such as sulfur hexafluoride as insulating medium. GIL has the advantages of large transmission capacity, low loss, easy installation, high reliability, and no influence from external environmental factors such as dust, humidity and ice. It is suitable for power transmission occasions with harsh weather environment or limited corridor selection. It can partially replace traditional overhead lines and power cables and can be used for large-capacity and long-distance power transmission.

[0003] Among them, the insulator is mainly used to support the central guide rod and keep it insulated from the ground. The insulator is a high-resistivity epoxy resin doped with Al2O3, which is widely used in AC GIL. Due to the accumulation of surface charge on the insulator, and the extremely slow dissipation of surface charge on the insulator, it is easy to cause surface flashover. Therefore, DC GIL insulator is still one of the key factors restricting the development of DC GIL.

[0004] Accurately measuring the charge distribution on the surface of insulators is a prerequisite for studying charge accumulation. The structure of three-pillar insulators is complex and difficult to measure. At present, the research on the surface charge accumulation phenomenon of three-pillar insulators by domestic and foreign scholars is still in the experimental stage. The gap between the three pillars and the cavity is too small for general devices to measure. Therefore, the general insulator surface charge measurement system can only measure the charge on the left and right sides of the insulator step by step, and it is impossible to clearly determine where the surface charge accumulates significantly. At the same time, the surface of the three pillars has an arc, and general devices cannot keep the detection device perpendicular to the surface of the three pillars. At present, there is no measurement device that can conduct surface charge measurement research on the left and right sides of the GIL three-pillar insulator at one time. Utility Model Content

[0005] In view of the deficiencies in the prior art, the purpose of the utility model is to provide a surface charge measuring device for a three-pillar insulator of a high-voltage direct current GIL.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] A surface charge measuring device for a high-voltage direct current GIL three-pillar insulator is provided with an experimental chamber, the experimental chamber is sealed with a cover plate, a high-voltage guide rod is arranged in the experimental chamber, the high-voltage guide rod is sleeved with a central guide rod, the central guide rod passes through the three-pillar insulator, an electric slide rail is arranged at the bottom of the experimental chamber, a charge measuring device is slidably installed above the electric slide rail, the charge measuring device comprises a capacitance probe and a capacitance probe control device, the capacitance probe control device controls the capacitance probe to be vertical to the surface of the three-pillar insulator, and the capacitance probe is connected to a data acquisition device.

[0008] The capacitance probe control device comprises a base, three mechanical arms and a capacitance probe connecting frame. The base is slidably installed above the electric slide rail. A first servo motor is arranged on one side of the top of the base. The output shaft of the first servo motor is connected to the first mechanical arm. The first mechanical arm is connected to the second mechanical arm through the second servo motor. The second mechanical arm is connected to the third mechanical arm through the third servo motor. The first servo motor, the second servo motor and the third servo motor respectively control the forward and backward tilting of the first mechanical arm, the second mechanical arm and the third mechanical arm; a fourth servo motor is arranged on the top of the third mechanical arm. The output shaft of the fourth servo motor is connected to the capacitance connecting frame. The capacitance probe connecting frame is provided with a capacitance probe. The fourth servo motor controls the rotation of the capacitance probe connecting frame so that the capacitance probe is perpendicular to the surface of the three-pillar insulator; a fifth servo motor is arranged on the other side of the top of the base. A bearing is arranged on the outer side of the motor housing of the first servo motor. The output shaft of the fifth servo motor is connected to the bearing through belt transmission. The electric slide rail, the first servo motor, the second servo motor, the third servo motor, the fourth servo motor and the fifth servo motor are connected to the host.

[0009] The electric slide rails are located below the central guide rod and are parallel to each other.

[0010] The base is provided with a groove matched with the electric slide rail.

[0011] The data acquisition device includes a Trek electrostatic voltmeter, an oscilloscope, and a high impedance box. The Trek electrostatic voltmeter is arranged above the capacitance probe, and the Trek electrostatic voltmeter is sequentially connected to the high impedance box and the oscilloscope on the outer wall of the experimental chamber. The Trek electrostatic voltmeter is used to output the surface charge collected by the electrostatic probe; the high impedance box protection circuit prevents the oscilloscope from being burned out by excessive current; and the oscilloscope is used to store and display the surface charge.

[0012] An epoxy resin sheet is arranged between the capacitance probe connection frame and the capacitance probe, which ensures the sealing between the capacitance probe connection frame and the capacitance probe, thereby maintaining electrical insulation.

[0013] Beneficial effects of the utility model:

[0014] 1. The utility model can measure the surface charge on the front and back sides of the three-pillar insulator sample, which improves the problem that most experimental devices at this stage can only measure the surface charge on one side of the three-pillar insulator in a single experiment, and can avoid the error of the measurement result caused by two experiments. At the same time, the experimental time is greatly shortened, the experimental gas is greatly reduced, and it is more economical.

[0015] 2. The capacitance probe control device of the utility model is relatively flexible and can accurately control the movement distance and angle of each mechanical arm, and can make each mechanical arm of the capacitance probe control device extend into a straight line, which is convenient for transportation and storage.

[0016] 3. The utility model can be applied to various voltage forms, including AC voltage, DC voltage, impulse voltage, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic diagram of the structure of a device for measuring the surface charge of a three-pillar insulator of a high-voltage direct current GIL according to the utility model;

[0018] Figure 2 A schematic diagram of the structure of the charge measuring device of the utility model;

[0019] In the figure: 1. experimental chamber; 2. cover plate; 3. high-voltage guide rod; 4. center guide rod; 5. three-pillar insulator; 6. electric slide rail; 7. charge measuring device; 701. capacitance probe; 702. capacitance probe connecting frame; 703. base; 704. first section of the mechanical arm; 705. second section of the mechanical arm; 706. third section of the mechanical arm; 707. first servo motor; 708. second servo motor; 709. third servo motor; 710. fourth servo motor; 711. fifth servo motor; 712. belt; 713. host; 8. high impedance box; 9. oscilloscope. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0021] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0022] like Figure 1-2As shown, a surface charge measuring device for a three-pillar insulator of a high-voltage direct current GIL is provided, wherein an experimental chamber 1 is provided, the experimental chamber 1 is sealed with a cover plate 2, a high-voltage guide rod 3 is provided in the experimental chamber 1, the high-voltage guide rod 3 is sleeved with a central guide rod 4, the central guide rod 4 passes through a three-pillar insulator 5, an electric slide rail 6 is provided at the bottom of the experimental chamber 1, a charge measuring device 7 is slidably installed above the electric slide rail 6, the charge measuring device 7 comprises a capacitance probe 701 and a capacitance probe control device, the capacitance probe control device controls the capacitance probe 701 to be perpendicular to the surface of the three-pillar insulator 5, and the capacitance probe 701 is connected to a data acquisition device.

[0023] The capacitance probe control device comprises a base 703, three mechanical arms and a capacitance probe connecting frame 702. The base 703 is slidably mounted above the electric slide rail 6. A first servo motor 707 is provided on one side of the top of the base 703. The output shaft of the first servo motor 707 is connected to the first mechanical arm 704. The first mechanical arm 704 is connected to the second mechanical arm 705 through the second servo motor 708. The second mechanical arm 705 is connected to the third mechanical arm 706 through the third servo motor 709. The first servo motor 707, the second servo motor 708 and the third servo motor 709 respectively control the first mechanical arm 704, the second mechanical arm 705 and the third mechanical arm 706 to tilt forward and backward. A fourth servo motor 710 is provided on the top of the third mechanical arm 706. The output shaft of the fourth servo motor 710 is connected to the capacitance probe connecting frame 702. A connecting frame 702, a capacitance probe 701 is arranged on the capacitance probe connecting frame 702, and a fourth servo motor 710 controls the capacitance probe connecting frame 702 to rotate so that the capacitance probe 701 is perpendicular to the surface of the three-pillar insulator 5; a fifth servo motor 711 is arranged on the other side of the top of the base 703, a bearing is arranged on the outer side of the motor housing of the first servo motor 707, and the output shaft of the fifth servo motor 711 is connected to the bearing through a belt 712 transmission, and the electric slide 6, the first servo motor 707, the second servo motor 708, the third servo motor 709, the fourth servo motor 710, and the fifth servo motor 711 are connected to the host 713, and the host 713 controls the movement of the electric slide 6, the first servo motor 707, the second servo motor 708, the third servo motor 709, the fourth servo motor 710, and the fifth servo motor 711.

[0024] The electric slide rails 6 are located below the central guide rod 4 and are parallel to each other.

[0025] The base 703 is provided with a groove matching with the electric slide rail 6 .

[0026] The data acquisition device includes a Trek electrostatic voltmeter, an oscilloscope 9, and a high impedance box 8. The Trek electrostatic voltmeter is arranged above the capacitance probe 701, and the Trek electrostatic voltmeter is sequentially connected to the high impedance box 8 and the oscilloscope 9 on the outer wall of the experimental chamber 1. The Trek electrostatic voltmeter is used to output the surface charge collected by the electrostatic probe; the high impedance box 8 amplifies and protects the signal by reducing the output load current to increase the input resistance of the circuit to prevent the oscilloscope from being burned out by excessive current; the oscilloscope 9 is used to store and display the surface charge.

[0027] An epoxy resin sheet is provided between the capacitance probe connection frame 702 and the capacitance probe 701 to ensure sealing between the capacitance probe connection frame 702 and the capacitance probe 701, thereby maintaining electrical insulation.

[0028] like Figure 1 As shown, two three-pillar insulators 5 are sleeved on the central guide rod 4, the one close to the end of the central guide rod 4 is the three-pillar insulator to be tested, and the other one provides support for the central guide rod 4. The measurement of the three-pillar insulator 5 described below refers to the three-pillar insulator to be tested close to the end of the central guide rod 4.

[0029] A device for measuring the surface charge of a three-pillar insulator of a high-voltage direct current GIL, the measuring steps are as follows:

[0030] Step 1: Check the air tightness of the experimental cavity 1, and then place the three-pillar insulator 5 inside the experimental cavity 1;

[0031] Step 2: When measuring the three-pillar insulator 5, both the front and back sides are measured. The side facing the charge measuring device 7 is the front side, and the side opposite to the front side is the back side. When measuring, the three-pillar insulator 5 is divided into two areas, the upper part and the lower part. The part above the center guide rod 4 is the upper part, and the part below the center guide rod is the lower part.

[0032] Step 3: Inflate the experimental chamber 1 with insulating gas until the required pressure is reached, then stop inflating;

[0033] Step 4: Turn on the power supply, apply voltage to both ends of the three-pillar insulator 5, and after applying the voltage to both ends of the three-pillar insulator 5 for 10 to 30 minutes, turn off the power supply and remove the voltage at both ends of the three-pillar insulator 5;

[0034] Step 5: Measure the front of the three-pillar insulator 5. The main machine is running, the electric slide 6 is started, and the charge measurement device 7 is moved to the vicinity of the front of the three-pillar insulator 3. The first servo motor 707, the second servo motor 708, and the third servo motor 709 adjust the forward and backward tilt angles of the first mechanical arm 704, the second mechanical arm 705, and the third mechanical arm 706 to meet the measurement height of the three-pillar insulator 5. When measuring the upper part, the first mechanical arm 704, the second mechanical arm 705, and the third mechanical arm 706 can be kept in a vertical state at the same time. When measuring the lower part, the first mechanical arm 704, the second mechanical arm 705, and the third mechanical arm 706 can be kept parallel to the electric slide 6 at the same time; at the same time, the fourth servo motor 710 controls the capacitance probe frame 702 to rotate, thereby driving the capacitance probe 701 to rotate so that it is perpendicular to the surface of the three-pillar insulator 5, and the capacitance probe 701 is 2mm away from the surface of the three-pillar insulator 5. Start the capacitance probe 701 to scan the surface of the three-pillar insulator 5;

[0035] Step 6: Measure the reverse side of the three-pillar insulator 5. The fifth servo motor 711 is driven by the belt 712 to rotate the first servo motor 707 by a certain angle, so that the charge measuring device 7 goes around the side of the three-pillar insulator 5. At the same time, the first servo motor 707, the second servo motor 708, and the third servo motor 709 adjust the forward and backward tilt angles of the first mechanical arm 704, the second mechanical arm 705, and the third mechanical arm 706, so that the first mechanical arm 704, the second mechanical arm 705, and the third mechanical arm 706 extend through the gap between the three-pillar insulator 5 and the inner wall of the experimental cavity 1 to the reverse side of the three-pillar insulator 5. At this time, the capacitance probe 701 is adjusted by the fourth servo motor 710 so that the capacitance probe 701 is perpendicular to the surface of the three-pillar insulator 5, and the capacitance probe 701 is 2 mm away from the surface of the three-pillar insulator 5. The capacitance probe 701 is started to scan the surface of the three-pillar insulator 5.

[0036] Step 7: The Trek electrostatic voltmeter outputs the surface charges on the front and back sides of the three-pillar insulator 5 collected by the electrostatic probe 701, and stores and displays them through the oscilloscope 9;

[0037] Step eight: discharge the three-pillar insulator 5. After the discharge is completed, the surface of the three-pillar insulator 5 needs to be processed again to remove the charge accumulated on the surface of the three-pillar insulator 5 during the measurement process, so as to eliminate the influence of the residual charge on the next measurement.

[0038] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model is described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the utility model 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 utility model should be included in the scope of the claims.

Claims

1. A surface charge measurement device for a three-pillar insulator of a high-voltage direct current GIL, comprising an experimental chamber, the experimental chamber being sealed with a cover plate, a high-voltage guide rod being arranged in the experimental chamber, the high-voltage guide rod being sleeved with a central guide rod, and the central guide rod passing through the three-pillar insulator, characterized in that: An electric slide is provided at the bottom of the experimental chamber, and a charge measuring device is slidably installed above the electric slide. The charge measuring device includes a capacitance probe and a capacitance probe control device. The capacitance probe control device controls the capacitance probe to be vertical to the surface of the three-pillar insulator, and the capacitance probe is connected to a data acquisition device.

2. The surface charge measuring device for three-pillar insulators of a high-voltage direct current GIL according to claim 1 is characterized in that: The capacitance probe control device comprises a base, three mechanical arms and a capacitance probe connecting frame. The base is slidably installed above the electric slide rail. A first servo motor is arranged on one side of the top of the base. The output shaft of the first servo motor is connected to the first mechanical arm. The first mechanical arm is connected to the second mechanical arm through the second servo motor. The second mechanical arm is connected to the third mechanical arm through the third servo motor. The first servo motor, the second servo motor and the third servo motor respectively control the forward and backward tilting of the first mechanical arm, the second mechanical arm and the third mechanical arm; a fourth servo motor is arranged on the top of the third mechanical arm. The output shaft of the fourth servo motor is connected to the capacitance connecting frame. The capacitance probe connecting frame is provided with a capacitance probe. The fourth servo motor controls the rotation of the capacitance probe connecting frame so that the capacitance probe is perpendicular to the surface of the three-pillar insulator; a fifth servo motor is arranged on the other side of the top of the base. A bearing is arranged on the outer side of the motor housing of the first servo motor. The output shaft of the fifth servo motor is connected to the bearing through belt transmission. The electric slide rail, the first servo motor, the second servo motor, the third servo motor, the fourth servo motor and the fifth servo motor are connected to the host.

3. The surface charge measuring device for three-pillar insulators of a high-voltage direct current GIL according to claim 1 is characterized in that: The electric slide rails are located below the central guide rod and are parallel to each other.

4. The surface charge measuring device for three-pillar insulators of a high-voltage direct current GIL according to claim 2 is characterized in that: The base is provided with a groove matched with the electric slide rail.

5. The surface charge measuring device for three-pillar insulators of a high-voltage direct current GIL according to claim 1 is characterized in that: The data acquisition device comprises a Trek electrostatic voltmeter, an oscilloscope and a high impedance box. The Trek electrostatic voltmeter is arranged above the capacitance probe, and the Trek electrostatic voltmeter is sequentially connected to the high impedance box and the oscilloscope on the outer wall of the experimental chamber.

6. The surface charge measuring device for three-pillar insulators of a high-voltage direct current GIL according to claim 2, characterized in that: An epoxy resin sheet is arranged between the capacitance probe connecting frame and the capacitance probe.

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