A voltage divider and GIS device

Abstract

The application provides a divider, which comprises a basin insulator, a shell, a flange, a terminal block, a high-voltage arm and a low-voltage arm. The shell is a cylindrical structure, the terminal block is arranged at a terminal outlet of the flange, the basin insulator and the flange are connected with two ends of the shell respectively, and the basin insulator, the shell, the flange and the terminal block form an air chamber. The high-voltage arm is located in the air chamber, and a high-voltage end of the high-voltage arm is connected with the basin insulator, and a low-voltage end of the high-voltage arm is connected with the flange. In the high-voltage arm, a resistance string and a capacitor string are connected through a wire and are covered in a resistance shielding cylinder. The high-voltage end of the low-voltage arm is electrically connected with the low-voltage end of the high-voltage arm. Since the voltage-sharing ceramic resistance shielding cylinder is provided with a resistance layer, a small current flows from the high-voltage end to the low-voltage end, and then enters the flange, thereby forming an electrical shielding structure with a smooth surface, the electric field intensity of the surface can be greatly reduced, the influence of the external environment on the divider can be prevented, the stability and precision of equipment measurement are provided, and the product volume is reduced. The application also provides a GIS device with the above-mentioned divider.

Description

Technical Field

[0001] This invention belongs to the field of high voltage measurement technology, and specifically relates to a voltage divider and GIS equipment. Background Technology

[0002] The high-voltage arm of a voltage divider, as a key component for equipment measurement, is generally composed of metal film resistors with high temperature coefficients and good electrical characteristics connected in series and then wound around an insulating cylinder to form the high-voltage arm. This structure is currently mostly used in open-type voltage transformers. When this structure is used with GIS voltage transformers, the outer surface of the high-voltage arm is significantly rougher than the outer surface of the conductors used in other components of the GIS. When the equipment's voltage increases, the electric field strength on the outer surface of the high-voltage arm is extremely high, leading to a decrease in the equipment's insulation performance. In severe cases, the high-potential portion of the high-voltage arm can discharge to the casing. Therefore, a reasonable structure needs to be designed to ensure that the measurement of the high-voltage arm of the voltage divider is not affected, while also ensuring a reasonable potential distribution and controlled electric field strength within a certain range in both the axial and radial directions of the high-voltage arm, thereby improving the product's insulation performance.

[0003] Compared to open-type power plants, the distance between sub-equipment in GIS equipment is short. During VFTO, if the RC divider is not shielded, it will be affected by interference from other sub-equipment, and the measurement results will deviate from the actual results. Therefore, electromagnetic interference protection is required for the RC divider.

[0004] In addition, the resistors wound around the insulating tube will form an inductance, which is detrimental to the operation of the product under impulse voltage.

[0005] Therefore, how to improve the insulation performance of voltage dividers and form electromagnetic interference protection is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to provide a voltage divider and GIS equipment that can improve the insulation performance of the voltage divider and provide electromagnetic interference protection.

[0007] To solve the above-mentioned technical problems, the present invention provides a voltage divider, including a basin insulator, a housing, a flange, a terminal block, a high-voltage arm and a low-voltage arm;

[0008] The housing is a cylindrical structure with openings at both the top and bottom. The terminal block is placed at the outlet of the flange. The basin-type insulator and the flange are respectively connected to the upper and lower ends of the housing. The basin-type insulator, the housing, the flange, and the terminal block form an air chamber.

[0009] The high-voltage arm is located in the air chamber and its high-voltage end is connected to the basin insulator, and its low-voltage end is connected to the flange. The high-voltage arm includes a resistor shielding cylinder, a resistor string and a capacitor string. The resistor string and the capacitor string are connected by wires and are covered in the resistor shielding cylinder. The resistor shielding cylinder is a voltage-equalizing ceramic resistor shielding cylinder with a resistor layer on its outer surface and its surface is smooth.

[0010] The high-voltage end of the low-voltage arm is electrically connected to the low-voltage end of the high-voltage arm.

[0011] Preferably, the voltage divider further includes a contact base and a contact head, wherein the top end of the contact base is connected to the basin insulator and the bottom end is connected to the top end of the contact head, and the bottom end of the contact head is connected to the high-voltage end of the high-voltage arm.

[0012] Preferably, in the voltage divider described above, an upper flange and a lower flange are respectively provided at both ends of the resistor shielding cylinder, the upper flange is electrically connected to the contact, and the lower flange is fixedly connected to the flange.

[0013] Preferably, in the above-mentioned voltage divider, the basin-type insulator may also have a through hole for communicating with other air chambers.

[0014] Preferably, the voltage divider further includes an insulating tube, the resistor string is wound around the outer wall of the insulating tube, the high voltage end of the resistor string is electrically connected to the high voltage end of the resistor shielding cylinder and the lower end is insulated from the resistor shielding cylinder.

[0015] Preferably, in the voltage divider described above, the resistors are wound in series on the insulating tube in both forward and reverse directions at intervals.

[0016] Preferably, in the voltage divider described above, the capacitor string is composed of multiple capacitor units connected in series, the resistor string is composed of multiple resistor units connected in series, the high-voltage end of the capacitor string is electrically connected to the high-voltage end of the resistor string, and the low-voltage end of the capacitor string is electrically connected to the low-voltage end of the resistor string, forming the measurement module of the high-voltage arm.

[0017] Preferably, in the voltage divider described above, the capacitor string includes multiple capacitor units connected in series, the resistor string includes multiple resistor units connected in series, one capacitor string and one resistor string are connected in parallel to form a resistor-capacitor unit, and the multiple identical resistor-capacitor units are connected in series to form the measurement module of the high voltage arm.

[0018] Preferably, the voltage divider further includes a housing covering the low-pressure arm, the housing having an opening at the top, and the opening end of the housing being connected to the flange.

[0019] Preferably, the voltage divider further includes a data acquisition module for detecting the output voltage of the low-voltage arm. The data acquisition module converts the acquired data into an optical signal and transmits it to the merging unit for use in the control, protection, and measurement system.

[0020] Preferably, in the above-mentioned voltage divider, the high-pressure arm and the low-pressure arm are multiphase.

[0021] Preferably, in the voltage divider described above, each phase of the high-voltage arm includes a high-voltage arm resistor and a high-voltage arm capacitor connected in parallel, each phase of the low-voltage arm includes a low-voltage arm resistor and a low-voltage arm capacitor connected in parallel, and a limiting device is also connected in parallel on the low-voltage arm.

[0022] This case also provides a GIS device, including the voltage divider described above.

[0023] This invention provides a voltage divider, including a basin-type insulator, a housing, a flange, a terminal block, a high-voltage arm, and a low-voltage arm. The housing is a cylindrical structure open at both the top and bottom. The terminal block is located at the flange outlet. The basin-type insulator and the flange are connected to the upper and lower ends of the housing, respectively. The basin-type insulator, housing, flange, and terminal block form an air chamber. The high-voltage arm is located within the air chamber, with its high-voltage end connected to the basin-type insulator and its low-voltage end connected to the flange. The high-voltage arm includes a resistor shielding cylinder, a resistor string, and a capacitor string. The resistor string and capacitor string are connected by wires and enclosed within the resistor shielding cylinder. The high-voltage end of the low-voltage arm is electrically connected to the low-voltage end of the high-voltage arm. Because the equalizing ceramic resistor shielding cylinder has a resistive layer, a small current flows from the high-voltage end to the low-voltage end and then into the flange, forming a smooth-surface electrical shielding structure. The electric field strength on its surface can be greatly reduced, and the influence of the external environment on the voltage divider can be prevented, improving the stability and accuracy of the equipment measurement and reducing the product size. This invention also provides a GIS device with the above-mentioned voltage divider. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the voltage divider provided by the present invention;

[0026] Figure 2 for Figure 1 Top view;

[0027] Figure 3 A schematic diagram of the electrode connection between the high-voltage arm and the basin insulator provided by the present invention;

[0028] Figure 4 This is a schematic diagram of the current transformer for single-phase voltage measurement of GIS provided by the present invention;

[0029] Figure 5 The electrical schematic diagram of the voltage divider under three-phase voltage provided by this invention;

[0030] Figure 6 The electrical schematic diagram of the voltage divider under single-phase voltage provided by the present invention.

[0031] In the image above:

[0032] 1-Pot-type insulator; 2-Casing; 3-Flange; 4-A-phase high-voltage arm; 5-B-phase high-voltage arm; 6-C-phase high-voltage arm; 7-Shell; 8-A-phase low-voltage arm; 9-B-phase low-voltage arm; 10-C-phase low-voltage arm; 11-Terminal panel; 12-Contact base; 13-Contact; 14-Resistor shielding cylinder; 15-Resistor string; 16-Capacitor string;

[0033] Ra - equalizing resistor; R1a - high voltage arm resistor; C1a - high voltage arm capacitor; R2a - low voltage arm resistor; C2a - low voltage arm capacitor; Fa - limiting device;

[0034] Rb - Equalizing resistor; R1b - High voltage arm resistor; C1b - High voltage arm capacitor; R2b - Low voltage arm resistor; C2b - Low voltage arm capacitor; Fb - Limiting device;

[0035] Rc - equalizing resistor; R1c - high voltage arm resistor; C1c - high voltage arm capacitor; R2c - low voltage arm resistor; C2c - low voltage arm capacitor; Fc - limiting device. Detailed Implementation

[0036] The core of this invention is to provide a voltage divider and GIS equipment, which can improve the insulation performance of the voltage divider and provide electromagnetic interference protection.

[0037] To enable those skilled in the art to better understand the technical solutions provided by the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0038] Please refer to Figures 1-6 , Figure 1 This is a schematic diagram of the voltage divider provided by the present invention; Figure 2 for Figure 1 Top view; Figure 3 A schematic diagram of the electrode connection of the high-voltage arm, the resistor shielding cylinder, and the insulating basin provided by the present invention; Figure 4 This is a schematic diagram of the current transformer for single-phase voltage measurement of GIS provided by the present invention; Figure 5 The electrical schematic diagram of the voltage divider under three-phase voltage provided by this invention; Figure 6The electrical schematic diagram of the voltage divider under single-phase voltage provided by the present invention.

[0039] The present invention provides a voltage divider, comprising a basin insulator 1, a housing 2, a flange 3, a terminal block 11, a high-voltage arm, and a low-voltage arm;

[0040] Among them, the shell 2 is a cylindrical structure with openings at both the top and bottom. The terminal block 11 is placed at the outlet of the flange 3. The basin insulator 1 and the flange 3 are connected to the upper and lower ends of the shell 2 respectively. The basin insulator 1, the shell 2, the flange 3 and the terminal block 11 form an air chamber, and the gaps in the air chamber are filled with insulating medium.

[0041] The aforementioned air chamber provides an air chamber environment for the resistive-capacitive voltage transformer used in GIS, and can be connected to other GIS components through the basin-type insulator 1. It should be noted that this air chamber is mostly an independent, sealed chamber. However, it is also possible that the basin-type insulator 1 has an opening communicating with other air chambers; in this case, the air chamber is not sealed. Specifically, the basin-type insulator 1 has a through hole for communicating with other air chambers.

[0042] The high-voltage arm is located inside the gas chamber, with its high-voltage end connected to the basin-type insulator 1 and its low-voltage end connected to the flange 3. The high-voltage arm includes a resistor shielding cylinder 14, a resistor string 15, and a capacitor string 16, which together form the high-voltage arm of a resistive-capacitive voltage divider for measuring voltage. The resistor string 15 and capacitor string 16 are connected by wires and housed within the resistor shielding cylinder 14. The outer surface of the resistor shielding cylinder 14 is a smooth, voltage-equalizing ceramic resistor shielding cylinder with a resistive layer.

[0043] It should be noted that the resistor shielding cylinder 14 is equipped with a resistive film with a high resistance value, namely the voltage equalizing shielding resistor Ra, and the high-voltage arm of the RC voltage divider is installed inside it. The resistance of the resistive film needs to be determined according to the voltage value to be measured to ensure that it generates little heat, can conduct electricity and improve the electric field, and can also shield the high-voltage arm of the RC voltage divider installed inside it from external interference.

[0044] A small current flows from the high-voltage end to the low-voltage end on the equalizing ceramic resistor shielding cylinder, and then enters the flange, forming an electrical shielding structure. Its effect is twofold: firstly, it can prevent the external environment from affecting the voltage divider; secondly, due to its smooth outer surface, the surface electric field intensity can be greatly reduced.

[0045] The high-voltage end of the low-voltage arm is electrically connected to the low-voltage end of the high-voltage arm.

[0046] It should be noted that the voltage divider provided by this invention, in which the voltage-equalizing ceramic resistor shielding cylinder is sleeved outside the high-voltage arm of the resistive-capacitive voltage divider, has the following advantages when operating under power:

[0047] 1. Because the outer surface of the equalizing ceramic resistor shielding cylinder is a smooth ceramic cylinder, the electric field strength on its surface can be greatly reduced. When the gas pressure inside the shell is constant, the shell diameter can be reduced, which helps in product miniaturization. Similarly, with a fixed shell size, the insulating gas pressure is lower compared to solutions without an equalizing ceramic resistor shielding cylinder in order to ensure insulation capability.

[0048] 2. The potential of the high-voltage arm / equalizing ceramic resistor shielding cylinder gradually decreases from the high-voltage end to the low-voltage end. Furthermore, the coaxial electrode structure of the equalizing shielding resistor rod cylinder and rod with the GIS shell and other phases allows the potential of the equipment to decrease uniformly from the high-voltage end to the low-voltage end, improving the potential distribution and providing insulation performance.

[0049] 3. The equalizing ceramic resistor shielding cylinder can prevent the external environment from affecting the resistive-capacitive voltage divider, providing stability and accuracy for equipment measurements.

[0050] 4. Compared with electromagnetic and capacitive voltage transformers used in GIS, this solution integrates the RC voltage divider into the GIS very well. It has ample electrical insulation space, and the shell has a straight cylindrical structure, which significantly reduces the size.

[0051] 5. It can measure DC voltage or DC voltage components in GIS.

[0052] This solution improves the electric field and insulation by placing the equalizing ceramic resistor shielding cylinder on the high-voltage arm, effectively preventing the high-voltage arm of the voltage divider from being affected by the external electromagnetic environment.

[0053] In a specific implementation, the solution also includes a contact base 12 and a contact 13. The top end of the contact base 12 is connected to the basin insulator 1 and the bottom end is connected to the top end of the contact 13. The bottom end of the contact 13 is connected to the high-voltage end of the high-voltage arm.

[0054] like Figure 1 As shown, the high-voltage arms of phases a, b, and c are located in the gas chamber and installed on flange 3. Their high-voltage ends are fixed and electrically connected to the electrodes of phases a, b, and c of basin insulator 1 through contact seat 12 and contact 13.

[0055] The basin-type insulator electrode and the high-voltage end of the high-voltage arm are connected by contact 13 and contact base 12. Contact base 13, with its arc-shaped outer surface, can effectively improve the electric field at the high-voltage end of the high-voltage arm and reduce the electric field strength at the high-voltage end. Spring contact fingers are provided on the connection end of contact base 12 with contact 13.

[0056] Furthermore, the resistor shielding cylinder 14 is provided with an upper flange and a lower flange at both ends, the upper flange is electrically connected to the contact 13, and the lower flange is fixedly connected to the flange 3.

[0057] like Figure 3As shown, through holes are opened on the upper flange and the lower flange respectively. The upper flange is connected to the high-pressure end of the high-pressure arm through a wire, and the lower flange is connected to the high-pressure end of the low-pressure arm and the low-pressure end of the high-pressure arm through a wire.

[0058] In a specific embodiment, it also includes an insulating tube, with the resistor string 15 wound around the outer wall of the insulating tube. The high-voltage end of the resistor string 15 is electrically connected to the high-voltage end of the resistor shielding cylinder 14, and the lower end is insulated from the resistor shielding cylinder 14.

[0059] As shown in Figure 3, the resistor string 15 can be coiled and fixed on the outer wall of the insulating tube. The high-voltage end of the resistor string is electrically connected to the high-voltage end of the equalizing ceramic resistor shielding cylinder 14. The lower end of the resistor string is insulated from the equalizing ceramic resistor shielding cylinder 14 and can withstand a certain voltage.

[0060] To reduce the inductance of the resistor string, the resistor string 15 is wound alternately in both forward and reverse directions on the insulating tube, with the beginning and end of the resistor string fixed to the flanges at both ends of the insulating tube. In practical applications, the resistor string can be wound once on the insulating tube and then once in the opposite direction to reduce the inductance. Of course, some manufacturers do not require a non-inductive state, and the resistor string is wound in the same direction from top to bottom.

[0061] In one specific embodiment, the capacitor string 16 is composed of multiple capacitor units connected in series, and the resistor string 15 is composed of multiple resistor units connected in series. The high-voltage terminal of the capacitor string 16 is electrically connected to the high-voltage terminal of the resistor string 15, and the low-voltage terminal of the capacitor string 16 is electrically connected to the low-voltage terminal of the resistor string 15, forming a measurement module of the high-voltage arm.

[0062] It should be noted that the capacitor units can be cylindrical ceramic capacitors or other types of capacitors, and the capacitors can be connected to each other using wires or metal connecting flanges. The capacitors are connected in series to the upper and lower flanges of the insulating tube at the high-voltage and low-voltage ends, respectively.

[0063] In another specific embodiment, the capacitor string 16 includes multiple capacitor units connected in series, and the resistor string 15 includes multiple resistor units connected in series. A capacitor string 16 and a resistor string 15 are connected in parallel to form a resistor-capacitor unit. Multiple identical resistor-capacitor units are connected in series to form the measurement module of the high-voltage arm. The first group of resistor-capacitor units (high-voltage end) is electrically connected to the high-voltage end of the resistor shielding cylinder 14, and the last group of resistor-capacitor units (low-voltage end) is electrically connected to the high-voltage end of the low-voltage arm.

[0064] In both of the above implementations, the capacitor string 16 is composed of multiple capacitor units connected in series. The high-voltage end of the capacitor string is electrically connected to the high-voltage end of the resistor string, and the low-voltage end of the capacitor string is electrically connected to the low-voltage end of the resistor string, forming the high-voltage arm of the RC voltage divider. Alternatively, a resistor string and a capacitor string can be connected in parallel and then connected in series to form the high-voltage arm of the RC voltage divider.

[0065] In a preferred embodiment, the solution further includes a cover 7 mounted on the low-pressure arm, with an opening at the top and the opening end of the cover connected to the flange 3 for dust and rain protection.

[0066] Of course, the low-pressure arm can be set inside or outside the gas chamber, while the high-pressure arm is located inside the gas chamber. The high-pressure arm and the low-pressure arm together form a resistive-capacitive voltage divider for measuring the voltage to be measured inside the GIS.

[0067] This solution also includes a data acquisition module for detecting the output voltage of the low-voltage arm. The acquisition module measures the output voltage of the low-voltage arm, and the measured voltage value can be obtained through calculation. The acquisition module converts the acquired data into an optical signal and transmits it to the merging unit, which then transmits it to the control and protection measurement system. The acquisition module is located outside the voltage divider and is connected to the low-voltage arm via a line.

[0068] In specific implementations, the high-voltage arm and the low-voltage arm can be single-phase or multi-phase, i.e., two-phase or three-phase.

[0069] When using a single-phase high-voltage arm and a single-phase low-voltage arm, this implementation example is as follows: Figure 4 As shown, this scheme is for using a current transformer for GIS single-phase voltage measurement.

[0070] When a three-phase high-voltage arm and a three-phase low-voltage arm are used, this implementation example is as follows: Figure 1 and Figure 2 As shown, the three-phase high-voltage arms (a, b, and c) are located inside the gas chamber and mounted on flange 3. Their high-voltage ends are fixed and electrically connected to the electrodes of phases a, b, and c of the basin insulator 1 via contact seats 12 and contacts 13. The high-voltage arm consists of a voltage-equalizing ceramic resistor shielding cylinder 14, a resistor string 15, and a capacitor string 16. The resistor string 15 and capacitor string 16 form the high-voltage arm of the resistive-capacitive voltage divider for measuring voltage. Of course, a three-phase high-voltage arm and a three-phase low-voltage arm can also be used. Regardless of the number of phases used for the high-voltage and low-voltage arms, their connection methods with the basin insulator 1, housing 2, and flange 3 are the same, achieving the same technical effect.

[0071] Furthermore, each phase high-voltage arm includes high-voltage arm resistors and high-voltage arm capacitors connected in parallel, and each phase low-voltage arm includes low-voltage arm resistors and low-voltage arm capacitors connected in parallel. A limiting device is also connected in parallel on the low-voltage arm.

[0072] In the low-voltage arm, the limiting device Fa is connected in parallel with the low-voltage arm resistor R2a and the voltage arm capacitor C2a to protect against impulse voltage, so that the low-voltage arm and the acquisition module are not affected by large voltage impulses.

[0073] This solution can also be used for single-phase or two-phase applications. The following explanation uses three-phase as an example.

[0074] The product can measure three-phase voltage and uses the same gas chamber. Its electrical schematic diagram is shown below. Figure 5 Taking phase a as an example, in the voltage transformer, R1a, C1a, R2a, and C2a form a resistive-capacitive voltage divider for measuring the voltage. R1a is the high-voltage arm resistor, C1a is the high-voltage arm capacitor, R2a is the low-voltage arm resistor, and C2a is the low-voltage arm capacitor. Fa is a limiting device, connected in parallel with the low-voltage arm to prevent the low-voltage arm and the acquisition module from being subjected to large voltage surges under impulse voltage. Ra is a voltage-equalizing shielding resistor, using a high-voltage cylindrical ceramic resistor. The high-voltage arm of the resistive-capacitive voltage divider is installed inside the resistor shielding cylinder. During energized operation, the potential of the resistor shielding cylinder and the high-voltage arm gradually decreases synchronously along the axial direction from the high-voltage end to the low-voltage end until it approaches ground potential.

[0075] Furthermore, the outer surface of the resistor shielding cylinder is a smooth cylinder, forming a rod-cylinder, rod-rod coaxial electrode structure with the GIS shell and the Rb and Rc of other phases. This significantly reduces the electric field strength inside the equipment and improves the insulation performance. Simultaneously, the Ra value of the resistor shielding cylinder prevents the influence of the external environment on the resistive-capacitive voltage divider, providing stability and accuracy in equipment measurements. The Ra resistance value must be selected to ensure low power consumption, low heat generation, and effective conductivity, uniformity, and shielding.

[0076] Regarding grounding, the low-voltage end of the resistor shielding cylinder Ra is installed on a metal flange that is at the same potential as the casing, and is at the same potential as the casing; the low-voltage end of the low-voltage arm of the resistor-capacitor voltage divider is also connected to the metal flange, and has the same ground potential.

[0077] In the entire electrical system, R1a × C1a = R2a × C2a, which gives the resistor-capacitor voltage divider excellent response characteristics. When the high-voltage side of the equipment is AC voltage Ua, the low-voltage arm output voltage Uouta is approximately Uouta × C2a / C1a; when the high-voltage side of the equipment is DC voltage Ua, the low-voltage arm output voltage Uouta is approximately Uouta × R1a / R2a.

[0078] Similarly, it can be seen that the working principle of phase b and phase c is the same as that of phase a.

[0079] In a specific application example, such as Figures 1-2 As shown, this scheme is for a GIS three-phase voltage measurement transformer. The voltage divider includes a basin insulator 1, a housing 2, a flange 3, a-phase high-voltage arm 4, a-phase high-voltage arm 5, a-phase high-voltage arm 6, a terminal block 11, a-phase low-voltage arm 8, a-phase low-voltage arm 9, a-phase low-voltage arm 10, a data acquisition module, and a merging unit. The basin insulator 1, housing 2, flange 3, and terminal block 11 form the GIS chamber. The data acquisition module converts the acquired data into optical signals and transmits them to the merging unit for use by the control and protection measurement system.

[0080] In a specific application example, such as Figure 4As shown, this scheme is for a single-phase voltage measurement transformer for GIS. The voltage divider includes a basin insulator 1, a housing 2, a flange 3, a high-voltage arm, a low-voltage arm, and a data acquisition module. The basin insulator 1, housing 2, and flange 3 form the GIS air chamber. The low-voltage arm is located at the bottom of flange 3, outside the air chamber.

[0081] In addition, this application also discloses a GIS device, including the voltage divider disclosed in the above embodiments. Therefore, the GIS device with the voltage divider also has all the above-mentioned technical effects, which will not be described in detail here.

[0082] It should be noted that GIS (GAS INSULATED SWITCHGEAR) is the abbreviation for Gas Insulated Switchgear. GIS consists of voltage dividers, circuit breakers, disconnecting switches, grounding switches, instrument transformers, surge arresters, busbars, connectors, and outgoing terminals. All these devices or components are enclosed in a grounded metal casing filled with SF6 insulating gas at a certain pressure; hence, it is also called SF6 fully enclosed switchgear.

[0083] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0084] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A voltage divider, characterized in that, It includes a basin-type insulator (1), a housing (2), a flange (3), a terminal block (11), a high-voltage arm, and a low-voltage arm; the housing (2) is a metal housing; The housing (2) is a cylindrical structure with openings at both the top and bottom. The terminal block (11) is placed at the outlet of the flange (3). The basin insulator (1) and the flange (3) are respectively connected to the upper and lower ends of the housing (2). The basin insulator (1), the housing (2), the flange (3) and the terminal block (11) form an air chamber. The high-voltage arm is located in the gas chamber and its high-voltage end is connected to the basin insulator (1), and its low-voltage end is connected to the flange (3). The high-voltage arm includes a resistor shielding cylinder (14), a resistor string (15), and a capacitor string (16). The resistor string (15) and the capacitor string (16) are connected by wires and enclosed in the resistor shielding cylinder (14). The resistor shielding cylinder (14) is a voltage-equalizing ceramic resistor shielding cylinder with a resistance layer on its outer surface and its surface is smooth. The two ends of the resistor shielding cylinder (14) are respectively connected to the high-voltage end and the ground potential. A small current flows from the high-voltage end to the low-voltage end on the voltage-equalizing ceramic resistor shielding cylinder. The high-voltage end of the low-voltage arm is electrically connected to the low-voltage end of the high-voltage arm. It also includes an insulating tube, the resistor string (15) is wound around the outer wall of the insulating tube, the high voltage end of the resistor string (15) is electrically connected to the high voltage end of the resistor shielding cylinder (14) and the lower end is insulated from the resistor shielding cylinder (14); the resistor string (15) is wound on the insulating tube in both forward and reverse directions at intervals.

2. The voltage divider according to claim 1, characterized in that, It also includes a contact base (12) and a contact (13), the top end of the contact base (12) being connected to the basin insulator (1) and the bottom end being connected to the top end of the contact (13), the bottom end of the contact (13) being connected to the high-voltage end of the high-voltage arm.

3. The voltage divider according to claim 2, characterized in that, The resistor shielding cylinder (14) is provided with an upper flange and a lower flange at both ends. The upper flange is electrically connected to the contact (13), and the lower flange is fixedly connected to the flange (3).

4. The voltage divider according to claim 1, characterized in that, The basin-type insulator (1) may also have through holes for communicating with other air chambers.

5. The voltage divider according to claim 1, characterized in that, The capacitor string (16) is composed of multiple capacitor units connected in series, and the resistor string (15) is composed of multiple resistor units connected in series. The high voltage terminal of the capacitor string (16) is electrically connected to the high voltage terminal of the resistor string (15), and the low voltage terminal of the capacitor string (16) is electrically connected to the low voltage terminal of the resistor string (15), forming the measurement module of the high voltage arm.

6. The voltage divider according to claim 1, characterized in that, The capacitor string (16) includes multiple capacitor units connected in series, and the resistor string (15) includes multiple resistor units connected in series. One capacitor string (16) and one resistor string (15) are connected in parallel to form a resistor-capacitor unit. The multiple identical resistor-capacitor units are connected in series to form the measurement module of the high voltage arm.

7. The voltage divider according to claim 1, characterized in that, It also includes a cover (7) covering the low-pressure arm, the cover (7) having an opening at the top, and the opening end of the cover (7) being connected to the flange (3).

8. The voltage divider according to claim 1, characterized in that, It also includes a data acquisition module for detecting the output voltage of the low-voltage arm. The data acquisition module converts the acquired data into an optical signal and transmits it to the merging unit for use in the control and protection measurement system.

9. The voltage divider according to any one of claims 1-8, characterized in that, The high-pressure arm and the low-pressure arm are multiphase.

10. The voltage divider according to any one of claims 1-8, characterized in that, Each phase of the high-voltage arm includes high-voltage arm resistors and high-voltage arm capacitors connected in parallel, and each phase of the low-voltage arm includes low-voltage arm resistors and low-voltage arm capacitors connected in parallel. A limiting device is also connected in parallel to the low-voltage arm.

11. A GIS device, characterized in that, Includes the voltage divider as described in any one of claims 1-10.

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