Sulfur hexafluoride gas density relay based on bellows and Baden tube

Abstract

A sulfur hexafluoride gas density relay based on a bellows and a Baden tube is disclosed. The relay includes: a mechanical assembly comprising a front housing, a device connection connector, a dial, a display pointer, a control area vent pipe, a display area vent pipe, a core assembly, and a pressure regulating mechanism; the device connection connector is connected to the measured sulfur hexafluoride gas chamber; one end of the bellows in the core assembly is connected to the chassis, and the other end is connected to a top rod; one end of the Baden tube and one end of the bimetallic temperature compensation plate are both fixed to an end seat, and the other end of the Baden tube is sealed to the base to form a sealed cavity; the other end of the bimetallic temperature compensation plate is fixedly connected to an operating arm, and the upper part of the operating arm is connected to the core assembly; a pressure and temperature integrated sensor in the remote transmission electronic assembly is connected to the bellows, and a remote transmission circuit board is used for data transmission. This invention achieves higher precision adjustment, improves the accuracy of the density relay, enables more refined monitoring, and the display uses a Baden tube to achieve full-range display.

Description

Technical Field

[0001] This invention relates to the field of relay technology, and more particularly to a sulfur hexafluoride gas density relay based on a bellows and a Baden tube. Background Technology

[0002] With the increasing demands of power grids for smart grids and smart substations, and the development of unmanned substations towards networking and digitalization, online monitoring of the gas density status of SF6 electrical equipment has become increasingly common. Current gas density monitoring systems (gas density relays) widely employ intelligent SF6 gas density relays to collect and upload data on density, pressure, and temperature, achieving online gas density monitoring. Therefore, selecting a reliable remote-transmission density relay is particularly important.

[0003] However, the currently used intelligent SF6 gas density relay uses a single Baden tube as the pressure sensing element and a bimetallic temperature compensation plate to simultaneously drive the microswitch and display the pointer. The advantage is that the pointer display can be very synchronized with the measured gas density and pressure. However, it also has certain limitations and shortcomings. The debugging accuracy is not high, and the vibration resistance performance is difficult to meet the requirements of electrical equipment in actual application sites. When the electrical equipment is closed, the strong vibration of the electrical switch equipment can easily cause malfunctions and false alarms. Summary of the Invention

[0004] To address the problems existing in the prior art, the main objective of this invention is to provide a sulfur hexafluoride gas density relay based on a bellows and a Baden tube, thereby improving the relay's accuracy and enabling more precise and reliable monitoring of sulfur hexafluoride gas.

[0005] To achieve the above objectives, embodiments of the present invention provide a sulfur hexafluoride gas density relay based on a bellows and a Baden tube, the relay comprising: a mechanical component and a remote transmission electronic component;

[0006] The mechanical components include a front housing, an equipment connection connector, a dial, a display pointer, a control area vent pipe, a display area vent pipe, a dial core assembly, and a pressure regulating mechanism. The equipment connection connector, dial, display pointer, control area vent pipe, display area vent pipe, dial core assembly, and pressure regulating mechanism are housed within the front housing. The equipment connection connector is connected to the chamber containing the sulfur hexafluoride gas being measured. The display pointer is located on the dial. The pressure regulating mechanism is connected to the control area vent pipe and the equipment connection connector.

[0007] The watch movement assembly includes a bellows, a Baden tube, a push rod, a chassis, a movement, a base, an end seat, a hinge, a connecting rod, a bracket, a meshing spring, a pull rod, a micro switch, a support plate, a bimetallic temperature compensation plate, and an operating arm. One end of the bellows is connected to the chassis, and the other end is connected to the push rod. One end of the Baden tube and one end of the bimetallic temperature compensation plate are both fixed to the end seat, and the other end of the Baden tube is sealed to the base to form a sealed cavity. The sulfur hexafluoride gas being measured enters the Baden tube through the equipment connection joint and the vent pipe in the display area.

[0008] The other end of the bimetallic temperature compensation plate is fixedly connected to the operating arm, and the upper part of the operating arm is connected to the mechanism so that the mechanism drives the display pointer to rotate on the dial; one end of the top rod is connected to the connecting rod; the connecting rod is set on the hinge seat, and the other end of the connecting rod is connected to the pull rod; the bracket is fixed on the chassis, and the micro switch is set on the bracket;

[0009] One end of the engagement spring is fixed to the chassis, and the other end pulls the tie rod; the support plate is fixedly connected to the tie rod; when the gas pressure of the gas being measured in the bellows increases or decreases, the top rod increases or decreases accordingly, driving the connecting rod to form a lever structure through the hinge seat;

[0010] The remote transmission electronic component includes a rear housing, an integrated pressure and temperature sensor, and a remote transmission circuit board; the integrated pressure and temperature sensor and the remote transmission circuit board are located inside the rear housing; the integrated pressure and temperature sensor is connected to the bellows; and the remote transmission circuit board is used for data transmission.

[0011] Optionally, in one embodiment of the present invention, the watch core assembly further includes a guide seat and a support frame; wherein, the push rod is guided by the support frame and the guide seat as a guiding element, so that the displacement of the push rod is in the vertical direction.

[0012] Optionally, in one embodiment of the present invention, the watch movement assembly further includes a pin for connecting the top rod and the connecting rod.

[0013] Optionally, in one embodiment of the present invention, the watch core assembly further includes a sleeve and a cover plate; wherein the sleeve, the cover plate and the chassis form a sealed cavity that encloses the watch core, forming a relative cavity.

[0014] Optionally, in one embodiment of the present invention, the mechanical component further includes a tee connector, the three joints of which are respectively connected to the equipment connection connector, the pressure regulating mechanism and the control area vent pipe.

[0015] Optionally, in one embodiment of the present invention, the watch core assembly further includes an insulating pad disposed between the micro switch and the bracket.

[0016] Optionally, in one embodiment of the present invention, the watch core assembly further includes a locking nut, which is disposed at the upper end of the pull rod and is used to fix and lock the support plate to the pull rod.

[0017] Optionally, in one embodiment of the present invention, the watch core assembly further includes an adjusting screw for adjusting the gap between the support plate and the micro switch.

[0018] Optionally, in one embodiment of the present invention, the remote transmission electronic component further includes a signal sampling unit for receiving the action signal fed back by the micro switch.

[0019] Optionally, in one embodiment of the present invention, the remote transmission electronic component further includes an intelligent control unit, which is connected to the signal sampling unit, the pressure and temperature integrated sensor, and the remote transmission circuit board for data communication.

[0020] This invention uses a bellows as the pressure measuring element in the control section to achieve a high vibration resistance structure. By using the lever principle, the adjustment range of the control contacts is expanded, which can achieve higher precision adjustment, improve the accuracy of the density relay, and realize more precise monitoring of sulfur hexafluoride gas in electrical equipment. At the same time, the display section uses a Baden tube to achieve full-range display. Attached Figure Description

[0021] 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 will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of a sulfur hexafluoride gas density relay based on a bellows and a Baden tube according to an embodiment of the present invention.

[0023] Figure 2 This is a schematic diagram of the watch core component structure in an embodiment of the present invention;

[0024] Figure 3 This is a schematic diagram of the lever drive mechanism in an embodiment of the present invention;

[0025] Figure 4 This is a schematic diagram of the overall structure of the sulfur hexafluoride gas density relay based on a bellows and a Baden tube in an embodiment of the present invention.

[0026] Figure 5 This is a schematic diagram of the self-verification circuit in an embodiment of the present invention. Detailed Implementation

[0027] This invention provides a sulfur hexafluoride gas density relay based on a bellows and a Baden tube.

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] like Figure 1 The diagram shown is a schematic representation of a sulfur hexafluoride gas density relay based on a bellows and a Baden tube, according to an embodiment of the present invention. This invention uses a bellows as the pressure-sensing element in the control section to achieve a highly vibration-resistant structure. By utilizing the lever principle, the adjustment range of the control contacts is expanded, enabling higher precision adjustment and improving the accuracy of the density relay. This allows for more precise monitoring of sulfur hexafluoride gas within electrical equipment. Simultaneously, the display section uses a Baden tube, thus achieving full-range display. The relay shown in the diagram includes: a mechanical component 1 and a remote electronic component 2.

[0030] Mechanical component 1 includes a front housing 101, an equipment connection connector 102, a dial 106, a display pointer 107, a control area vent pipe 108, a display area vent pipe 110, a core assembly 109, and a pressure regulating mechanism 302. The equipment connection connector 102, dial 106, display pointer 107, control area vent pipe 108, display area vent pipe 110, core assembly 109, and pressure regulating mechanism 302 are housed within the front housing 101. The equipment connection connector 102 is connected to the chamber containing the sulfur hexafluoride gas being measured. The display pointer 107 is located on the dial 106. The pressure regulating mechanism 302 is connected to the control area vent pipe 108 and the equipment connection connector 102.

[0031] The watch movement assembly 109 includes a bellows 10902, a Baden tube 10919, a push rod 10903, a chassis 10901, a movement 10905, a base 10920, an end seat 10921, a hinge 10907, a connecting rod 10909, a bracket 10910, a meshing spring 10911, a pull rod 10912, a micro switch 10914, a support plate 10915, a bimetallic temperature compensation plate 10922, and an operating arm 10923. One end of the bellows 10902 is connected to the chassis 10901, and the other end is connected to the top rod 10903; one end of the Baden tube 10919 and one end of the bimetallic temperature compensation plate 10922 are both fixed on the end seat 10921, and the other end of the Baden tube 10919 is sealed and connected to the base 10920 to form a sealed cavity; wherein, the sulfur hexafluoride gas to be measured enters the Baden tube 10919 through the equipment connection joint 102 and the display area vent pipe 110.

[0032] The other end of the bimetallic temperature compensation plate 10922 is fixedly connected to the operating arm 10923, and the upper part of the operating arm 10923 is connected to the mechanism 10905 so that the mechanism 10905 drives the display pointer 107 to rotate on the dial 106; the push rod 10903 is connected to one end of the connecting rod 10909; the connecting rod 10909 is set on the hinge seat 10907, and the other end of the connecting rod 10909 is connected to the pull rod 10912; the bracket 10910 is fixed on the chassis 10901, and the micro switch 10914 is set on the bracket 10910.

[0033] One end of the engagement spring 10911 is fixed to the chassis 10901, and the other end pulls the pull rod 10912; the support plate 10915 is fixedly connected to the pull rod 10912; when the gas pressure of the gas being measured in the bellows 10902 increases or decreases, the top rod 10903 increases or decreases accordingly, driving the connecting rod 10909 to form a lever structure through the hinge seat 10907.

[0034] The remote transmission electronic component 2 includes a rear housing 201, a pressure and temperature integrated sensor 203, and a remote transmission circuit board 204; wherein, the pressure and temperature integrated sensor 203 and the remote transmission circuit board 204 are disposed inside the rear housing 201; the pressure and temperature integrated sensor 203 is connected to the bellows 10902; and the remote transmission circuit board 204 is used for data transmission.

[0035] As an embodiment of the present invention, the watch core assembly 109 further includes a guide seat 10904 and a support frame 10906; wherein, the push rod 10903 is guided by the support frame 10906 and the guide seat 10904 as guiding elements, so that the displacement of the push rod 10903 is in the vertical direction.

[0036] As an embodiment of the present invention, the watch movement assembly 109 further includes a pin 10908, which is used to connect the top rod 10903 and the connecting rod 10909.

[0037] As an embodiment of the present invention, the watch core assembly 109 further includes a sleeve 10924 and a cover plate 10918; wherein the sleeve 10924, the cover plate 10918 and the chassis 10901 form a sealed cavity that encloses the relative cavity.

[0038] As an embodiment of the present invention, the mechanical component 1 further includes a three-way connector 301, the three joints of which are respectively connected to the equipment connection connector 103, the pressure regulating mechanism 302 and the control area vent pipe 108.

[0039] As an embodiment of the present invention, the watch core assembly 109 further includes an insulating pad 10913, which is disposed between the micro switch 10914 and the bracket.

[0040] As an embodiment of the present invention, the watch core assembly 109 further includes a locking nut 10917, which is disposed on the upper end of the pull rod 10912 and is used to fix and lock the support plate 10915 to the pull rod 10912.

[0041] As an embodiment of the present invention, the watch core assembly 109 further includes an adjusting screw 10916, which is used to adjust the gap between the support plate 10915 and the micro switch 10914.

[0042] As an embodiment of the present invention, the remote transmission electronic component 2 further includes a signal sampling unit 303 for receiving the action signal fed back by the micro switch 10914.

[0043] In this embodiment, the remote transmission electronic component 2 also includes an intelligent control unit 304, which is connected to the signal sampling unit 303, the pressure and temperature integrated sensor 203, and the remote transmission circuit board 204 for data communication.

[0044] This invention relates to a high-precision self-calibrating remote-type sulfur hexafluoride (SF6) gas density relay using a bellows and Baden tube. The bellows serves as the pressure-sensing element in the control section, achieving a highly vibration-resistant structure. Utilizing the lever principle, the adjustment range of the control contacts is expanded, enabling higher-precision adjustment and improving the relay's accuracy. This allows for more precise monitoring of SF6 gas within electrical equipment. Simultaneously, the display section employs a Baden tube, achieving full-range display. This significantly enhances the relay's accuracy, enabling self-calibration. The intelligent control unit controls the gas pressure rise and fall of the pressure regulating mechanism, which, via the lever mechanism, activates the microswitch, thus actuating the relay contacts. After collecting and analyzing relevant data, the relay's accuracy and compliance can be determined, achieving high reliability and intelligence. This provides safer and more convenient service to the power grid, ensuring long-term reliable operation. Furthermore, the self-calibration function eliminates the need for manual maintenance, reducing power operation and maintenance costs.

[0045] In a specific embodiment of the present invention, such as Figure 1 As shown, the high-precision self-calibrating remote transmission sulfur hexafluoride gas density relay using a bellows + Baden tube in this invention mainly consists of a mechanical part and an independent remote transmission electronic part, namely, mechanical component 1 and remote transmission electronic component 2. The mechanical part consists of a display function area and a contact signal control function area. The display function area is implemented by using a Baden tube as a pressure measuring element to drive the mechanism and pointer display, thereby achieving full-range display. The contact signal control function area uses a bellows as a pressure measuring element, forming a bellows assembly mechanism, which greatly improves the vibration resistance. At the same time, the lever proportional amplification principle is used to amplify the contact signal control adjustment ratio, achieving precise adjustment control and improving the precision of contact signal control.

[0046] In this embodiment, the mechanical assembly 1 of the bellows-Bourdon tube high vibration-resistance high-precision self-calibration remote-transmission sulfur hexafluoride gas density relay mainly comprises: a front case 101, an equipment connection connector 102, a front cover 103, an instrument glass 104, a sealing gasket 105, a dial 106, an indicating pointer 107, a control area vent pipe 108, a movement assembly 109, a display area vent pipe 110, a three-way connector 301, and a pressure regulating mechanism 302. The remote transmission electronic assembly 2 comprises: a rear case 201, a rear cover 202, an integrated pressure and temperature sensor 203, a remote transmission circuit board 204, an on-line calibration contact signal sampling unit 303, and an intelligent control unit 304.

[0047] Wherein, the relay of the present invention has a self-calibration function: the intelligent control unit 304 controls the rise and fall of gas pressure of the pressure regulating mechanism 302, so that the micro switch acts through a lever mechanism, that is, the contact of the density relay acts, thereby the on-line calibration contact signal sampling unit sends a signal to the intelligent control unit. Then the intelligent control unit 304 collects the gas pressure and temperature values when the contact acts through the integrated pressure and temperature sensor 203, and automatically calculates and converts the values into the pressure value corresponding to the gas at 20°C, that is, the density value. This density value is compared with the theoretical alarm and locking contact parameter values initially set for the density relay: if the difference meets the accuracy requirement of the density relay itself, the relay is qualified; otherwise, it is unqualified. The calibration conclusion is transmitted to the background monitoring system for display through the remote transmission function of the density relay.

[0048] Thereby, the gas density monitoring for electrical equipment does not require manual maintenance, and the self-calibration function of the density relay meets the requirements of high reliability and high vibration resistance, ensures the safe operation of the power grid, and reduces the maintenance cost.

[0049] In this embodiment, as Figure 1 , Figure 2 shows, the bellows-Bourdon tube high vibration-resistance high-precision self-calibration remote-transmission sulfur hexafluoride gas density relay of the present invention can be used for available high-voltage electrical equipment, and is mainly composed of a mechanical assembly 1 and a remote transmission electronic assembly 2.

[0050] Wherein, the display area of the mechanical assembly 1 uses a Bourdon tube as a pressure measuring element to directly drive the pointer to form a display part; the control area of the mechanical assembly 1 uses a bellows as a pressure measuring element. Since the bellows structure is a relative cavity structure, there is air pressure inside and outside the bellows, and the force-bearing area is large, which can greatly improve the vibration resistance. The contact adjustment of the control part is realized through the transmission of the lever mechanism, which greatly improves the accuracy and precision.

[0051] Further, Figure 1The mechanical part 1 shown includes: front case 101, equipment connection connector 102, front cover 103, instrument glass 104, sealing gasket 105, dial 106, display pointer 107, control area vent pipe 108, instrument core assembly 109, display area vent pipe 110, tee connector 301, and pressure regulating mechanism 302.

[0052] Furthermore, Figure 2 The watch movement assembly 109 shown includes: a chassis 10901, a bellows 10902, a top rod 10903, a guide seat 10904, a movement 10905, a support frame 10906, a hinge seat 10907, a pin 10908, a connecting rod 10909, a bracket 10910, a meshing spring 10911, a pull rod 10912, an insulating pad 10913, a micro switch 10914, a support plate 10915, an adjusting screw 10916, a locking nut 10917, a cover plate 10918, a Baden tube 10919, a base 10920, an end seat 10921, a bimetallic temperature compensation plate 10922, an operating arm 10923, and a sleeve 10924.

[0053] Furthermore, Figure 1 The remote transmission electronic component 2 shown includes: a rear housing 201, a rear cover 202, a pressure and temperature integrated sensor 203, a remote transmission circuit board 204, an online verification contact signal sampling unit 303, and an intelligent control unit 304. The pressure and temperature integrated sensor 203 is fixed inside the rear housing 201 and is connected to the pressure measuring element bellows 10902 in the gas path.

[0054] In this embodiment, the front casing 101 of the mechanical assembly and the rear casing 201 of the remote electronic assembly are independent or separated from each other. One end of the pressure-sensing element Baden tube 10919 and one end of the bimetallic temperature compensation plate 10922 are both fixed to the end base 10921. The other end of the pressure-sensing element Baden tube 10919 is sealed to the base 10920 to form a sealed cavity. The other end of the bimetallic temperature compensation plate 10922 is fixedly connected to the operating arm 10923. The upper part of the operating arm 10923 is connected to the movement 10905. The movement 10905 drives the display pointer 107 to rotate on the dial 106. By utilizing the temperature-dependent characteristics of the bimetallic temperature compensation plate 10922, the actual pressure value is compensated to the pressure value of sulfur hexafluoride gas corresponding to 20°C, which is then indicated on the dial 106 to achieve the display function.

[0055] Meanwhile, the display section uses a Baden tube to achieve full-range display. One end of the pressure sensing element bellows 10902 is fixed to the chassis 10901, and the other end is connected to the push rod 10903. The push rod 10903 is guided by the support frame 10906 and the guide seat 10904, ensuring that the displacement of the push rod 10903 is vertical. One end of the push rod 10903 is connected to one end of the connecting rod 10909 via a pin 10908. The connecting rod 10909 is positioned on the hinge seat 10907 via the pin 10908. The other end of the connecting rod 10909 is connected to the pull rod 10912 via the pin 10908. The bracket 10910 is fixed to the chassis 10901. The micro switch 10914 is mounted on the bracket 10910, with an insulating pad 10913 used for insulation in the middle. One end of the engagement spring 10911 is fixed to the chassis 10901, and the other end pulls the pull rod 10912. The upper end of the pull rod 10912 is fixed and locked to the support plate 10915 with the pull rod 10912 using a locking nut 10917. An adjusting screw 10916 is installed on the support plate 10915 to adjust the gap with the micro switch 10914. The entire structure is enclosed by a sealed cavity formed by the chassis 10901, the sleeve 10924, and the cover plate 10918, forming a relative cavity.

[0056] When the gas pressure of the gas being measured inside the bellows 10902 increases or decreases, the push rod 10903 will also increase or decrease accordingly, driving the connecting rod 10909 to form a lever structure through the fixed point hinge 10907. According to the lever principle, the connecting rod 10909 and the pull rod 10912 will generate opposite lowering or raising movements at the connection end. The lowering or raising movement of the pull rod 10912 will drive the support plate 10915 and the adjusting screw 10916 to move in the same direction, triggering or disengaging the micro switch 10914 to form an on or off electrical signal, thereby realizing the control function.

[0057] Specifically, the working principle and process of the relay of the present invention are as follows: The density relay is connected to the sulfur hexafluoride gas chamber to be tested through the equipment connection connector 102. The sulfur hexafluoride gas enters the first interface of the three-way connector 301 through the gas pipe, and enters the chassis 10901 through the control area vent pipe 108 from the third interface of the three-way connector 301, and then enters the bellows 10902. The bellows 10902, together with the sleeve 10924 and the cover plate 10918, forms a sealed cavity. The sealed cavity is filled with sulfur hexafluoride gas at a constant temperature of 20°C as a relative compensation cavity. The filling pressure is calculated according to the rated filling pressure of sulfur hexafluoride gas in the electrical equipment under test.

[0058] When the pressure of sulfur hexafluoride gas inside the tested electrical equipment decreases, i.e., the pressure of sulfur hexafluoride gas inside the bellows 10902 decreases, the pressure of the two cavities inside and outside the bellows 10902 becomes unbalanced, causing the bellows 10902 to compress downwards, which in turn causes the push rod 10903 to move downwards. At the same time, the connection point between the connecting rod 10909 and the push rod 10903 moves downwards, while the connection point between the connecting rod 10909 and the pull rod 10912 moves upwards. The upward movement of the pull rod 10912 causes the support plate 10915 and the adjusting screw 10916 to move upwards, causing the adjusting screw 10916 to disengage from the micro switch 10914, thus generating an alarm or lockout electrical signal.

[0059] Conversely, when the sulfur hexafluoride gas inside the electrical equipment is charged to the rated pressure, the pressure of the sulfur hexafluoride gas inside the bellows 10902 increases, restoring pressure balance. The bellows 10902 stretches upward, causing the push rod 10903 to move upward. At the same time, the connection point between the connecting rod 10909 and the push rod 10903 moves upward, while the connection point between the connecting rod 10909 and the pull rod 10912 moves downward. The downward movement of the pull rod 10912 causes the support plate 10915 and the adjusting screw 10916 to move downward, causing the adjusting screw 10916 to trigger the micro switch 10914 to release the alarm or lock the electrical signal, thus realizing the control function. On the other hand, the sulfur hexafluoride gas being measured enters the pressure measuring element Baden tube 10919 from the base 10920 through the equipment connection joint 102 and the display area vent pipe 110.

[0060] Furthermore, when the gas pressure in the measured sulfur hexafluoride gas chamber rises, the end of the pressure measuring element Baden tube 10919 undergoes a corresponding elastic deformation displacement, which is transmitted to the mechanism 10905 through the bimetallic temperature compensation plate 10922. The mechanism 10905 then transmits the information to the display pointer 107, and the pressure value of the measured sulfur hexafluoride gas at 20°C is then displayed on the dial 106 to achieve the display function.

[0061] In this embodiment, the high vibration resistance and high precision technology of the relay of the present invention operates on the following principle and process: The pressure measurement principle structure used in the control area is a bellows relative cavity structure. The inner cavity of the bellows 10902 is the measured sulfur hexafluoride gas cavity (hereinafter referred to as the measured gas cavity). The outer part of the bellows 10902, together with the sleeve 10924 and the cover plate 10918, forms a sealed cavity, which is the relative compensation cavity (hereinafter referred to as the reference gas cavity). During operation, both the measured gas cavity and the reference gas cavity are filled with sulfur hexafluoride gas. The pressure of the inner and outer cavities is balanced, effectively ensuring the stability of the push rod 10903. Even under strong vibration and impact during the opening and closing of electrical equipment, stability is still guaranteed, avoiding false alarms and malfunctions of the density relay. Compared with the density relay using the Baden tube as the pressure measuring element in the control area, the vibration resistance of the bellows structure of the present invention far exceeds that of the density relay using the Baden tube structure.

[0062] Among them, ultra-high precision technology, such as Figure 3 As shown, using the lever proportional amplification principle, the distance between the connection point of hinge 10907 and top rod 10903 is set as L1, and the distance between the connection point of hinge 10907 and pull rod 10912 is set as L2. According to the lever principle, when top rod 10903 rises or falls by a height H1, pull rod 10912 falls or rises in the opposite direction by H2, and H1:H2=L1:L2. Therefore, H2=L2 / L1*H1. Figure 3 (a) in the text represents a decrease in gas pressure (leakage). Figure 3 (b) in the figure represents the rated air pressure condition. Figure 3 (c) in the text represents an increase in gas pressure (inflation).

[0063] Furthermore, for conventional relative cavity bellows structure density relays, directly adjusting the control contacts by installing a microswitch on the top rod 10903 requires adjusting the control contacts to a level of 1.0. This would require adjusting the height of the adjustable range H1 to achieve this level of control. However, this invention uses a lever ratio amplification principle to expand the adjustable range to H2 = L2 / L1*H1. The height range H2 = L2 / L1*H1 easily achieves the accuracy requirement of level 1.0. Taking L1:L2 = 1:2, then H2 = 2H1. If the height of H1 can be adjusted to level 1.0, then the height of 2H1 can achieve an accuracy of level 0.5. Therefore, the larger the L1:L2 ratio is set, the higher and more precise the adjustable accuracy level.

[0064] Furthermore, the fixed point of the relay lever structure in this invention is the hinge seat 10907. During the rotation of the lever with the hinge seat as the center point, the movement trajectory of both ends of the lever is a circular trajectory with the center point of the hinge seat as the center. This will cause the top rod 10903 and the pull rod 10912 to have horizontal displacement. In order to convert the circular trajectory of the connection point at both ends of the lever rotation into the vertical displacement of the top rod 10903 and the pull rod 10912, an oblong hole with a horizontal guiding function is designed at the connection point of the top rod 10903 and the pull rod 10912. This effectively solves the problem of the lever movement trajectory, thereby realizing the ultra-high precision technology of the density relay.

[0065] In this embodiment, the working principle and process of the relay self-checking function technology of the present invention are as follows: the equipment connection connector 102 is connected to the first interface of the three-way connector 301 through the air pipe; the air path of the pressure regulating mechanism 302 is connected to the second interface of the three-way connector 301, and the third interface of the three-way connector 301 is connected to the chassis 10901 through the control area air pipe 108, and the air path leads to the bellows 10902.

[0066] When the background system issues a verification command, the intelligent control unit 304 transmits the command to the pressure regulating mechanism 302. The pressure regulating mechanism 302 then activates, performing a pressure reduction operation to lower the gas pressure entering the bellows 10902 from the third port of the tee connector 301. This reduces the pressure of the gas entering the bellows 10902 via the lever mechanism, which activates the micro switch 10914, i.e., the density relay contact. The activation signal of the micro switch 10914 is fed back to the online verification contact signal sampling unit 303. The online verification contact signal sampling unit 303 sends a signal to the intelligent control unit 304. Subsequently, the intelligent control unit 304 collects the gas pressure and temperature values ​​inside the bellows 10902 when the contact is activated from the pressure and temperature integrated sensor 203 and automatically calculates and converts them into the pressure value corresponding to 20°C gas.

[0067] Furthermore, the calculated pressure value corresponding to the 20°C gas is compared with the theoretical alarm and interlocking contact parameter values ​​initially set by the density relay. If the difference meets the accuracy requirements of the density relay itself, it is considered qualified; otherwise, it is considered unqualified. The verification result is transmitted to the background monitoring system for display through the remote transmission function of the density relay.

[0068] After the verification is completed, the intelligent control unit 304 transmits the end command to the pressure regulating mechanism 302. The pressure regulating mechanism 302 stops operating, so that the gas pressure entering the bellows 10902 from the third interface of the tee connector 301 is restored to be consistent with the gas pressure being measured in the gas chamber of the electrical equipment. The lever mechanism resets the micro switch 10914, thus the density relay resumes normal operation, and the entire self-verification process ends.

[0069] In a specific embodiment of the present invention, such as Figure 4 The diagram shows the overall structure of a bellows + Baden tube high-vibration-resistant, high-precision self-calibrating remote-transmission sulfur hexafluoride gas density relay. Its self-calibration function also includes: [following the previous sentence about a specific function, which is not directly related to the previous sentence about relays]. Figure 1 Compare the structural diagrams shown. Figure 4 The high-vibration-resistant, high-precision, self-calibrating, remote-transmission density relay with corrugated pipe and Baden pipe also includes: an external density relay adapter 3, a pressure regulating device 5, an electric control valve 4, a contact signal acquisition unit 6, an intelligent control unit 7, a multi-port connector 9, and an air inlet 10. The intelligent control unit 7 functions similarly to the intelligent control unit 304 in the previous embodiment.

[0070] The multi-port connector 9 is installed on the electrical equipment connection connector 8. One end of the solenoid valve 4 is fixed to the electrical equipment connection connector 8, and the other end of the solenoid valve 4 is fixed to one end of the multi-port connector 9, which connects to the gas path of the intelligent gas density relay body.

[0071] Furthermore, the electronically controlled valve 4 can also be connected to the intelligent control unit 7, and opened or closed under the control of the intelligent control unit 7. The pressure regulating device 5 can be connected to the intelligent gas density relay body through the multi-port connector 9. For example, the pressure regulating device 5 is fixed on the right port of the multi-port connector 9, and the pressure regulating device 5 is connected to the intelligent gas density relay body in the gas path.

[0072] Specifically, the pressure regulating device 5 is configured to regulate the rise and fall of the gas pressure in the intelligent gas density relay body, causing the intelligent gas density relay body to activate a contact signal. The upper end of the multi-port connector 9 is connected to the density relay adapter 3, and is fixedly connected to the density relay body via the density relay adapter 3. The lower end of the multi-port connector 9 is connected to the gas inlet 10.

[0073] Furthermore, the pressure regulating device 5 includes: a cavity with one open end, and a piston 51 inside the cavity. The piston 51 is provided with a sealing ring 510. One end of the piston 51 is connected to an adjusting rod, the outer end of which is connected to a driving component 52. The other end of the piston 51 extends into the opening and contacts the inner wall of the cavity. The driving component 52 drives the adjusting rod, thereby moving the piston 51 within the cavity. The driving component 52 includes, but is not limited to, one of the following: magnetic force, electric motor (variable frequency motor or stepper motor), reciprocating motion mechanism, Carnot cycle mechanism, or pneumatic component.

[0074] During normal operation, the solenoid valve 4 is in the open state, and the gas density relay monitors the gas density value inside the electrical equipment. At the same time, the gas density relay monitors the gas density value inside the electrical equipment online through the pressure and temperature integrated sensor 203 and the intelligent control unit 7.

[0075] In addition, the contact signal acquisition unit 6 is configured to acquire the contact signals of the gas density relay, and it is also connected to the intelligent control unit 7. The intelligent control unit 7 can be a microprocessor-based embedded system with embedded algorithms and control programs to automatically control the entire monitoring process, including all peripherals, logic, and input / output.

[0076] Among them, the bellows + Baden tube high vibration resistance, high precision self-calibrating remote transmission density relay can convert the pressure and temperature values ​​measured by the integrated pressure and temperature sensor 203 into the corresponding pressure value P20 at 20℃ according to the gas characteristics through the intelligent control unit 7. That is, the gas density relay has pressure and temperature measurement and software conversion functions. The intelligent control unit 7 can measure gas density relays of relative pressure and absolute pressure types.

[0077] Furthermore, the intelligent control unit 7 also has an interface that can complete test data storage, and / or test data export, and / or test data printing, and / or data communication with a host computer, and / or input analog and digital information. The pressure and temperature integrated sensor 203, the contact signal acquisition unit 6, and the intelligent control unit 7 are housed within the gas density relay body.

[0078] In this embodiment, the bellows + Baden tube high vibration resistance, high precision self-calibrating remote transmission density relay of the present invention also has human-machine interaction functions: it has a data display interface that can refresh the current data value in real time; it has a data input function that can input parameter setting values. The electrical interface of the gas density relay can have a protection function, so misconnection will not cause damage to the interface.

[0079] The intelligent control unit 7 and the intelligent control unit 304 can be implemented using general-purpose computers, industrial control computers, CPUs, microcontrollers, ARM chips, AI chips, quantum chips, photonic chips, MCUs, FPGAs, PLCs, industrial control motherboards, embedded main control boards, etc.

[0080] In this embodiment, as Figure 5 As shown, the gas density relay of this invention has a self-calibration function. The self-calibration working principle is as follows: based on the set calibration time and / or calibration command, and the gas density value, when the gas density relay is allowed to be calibrated, the intelligent control unit 7 controls the electronic control valve 4 to close, thereby cutting off the gas path between the gas density relay and the electrical equipment. The intelligent control unit 7 directly or indirectly adjusts the contact signal acquisition unit 6 to the calibration state.

[0081] In the verification state, the contact signal acquisition unit 6 cuts off the control circuit of the gas density relay contact signal. That is, the intelligent control unit 7 controls the contact signal acquisition unit 6 to de-energize the control coil of the intermediate relay J1 of the contact signal acquisition unit 6, and its contacts J11 and J12 are disconnected. In this way, the contact signal of the gas density relay is disconnected from the control circuit of the contact signal, and at the same time, the contact PJ of the gas density relay is connected to the intelligent control unit 7.

[0082] Furthermore, the intelligent control unit 7 controls the pressure regulating device 5, and simultaneously connects to the contact sampling circuit of the gas density relay body 1. Then, the intelligent control unit 7 controls the drive component 52 of the pressure regulating mechanism 5 (which can be mainly implemented using a motor and gears, with various and flexible methods), thereby adjusting the piston 51 of the pressure regulating mechanism 5, causing a volume change in the sealed cavity composed of the piston 51, the gas density relay body, and the valve 4. The gas pressure in the gas density relay body 1 gradually decreases, causing the density relay 1 to activate its contacts. This contact activation is uploaded to the intelligent control unit 7 via the online verification contact signal sampling unit 6.

[0083] Furthermore, the intelligent control unit 7 converts the pressure and temperature values ​​measured during contact operation into a pressure value P corresponding to 20°C according to the gas characteristics. 20 (Density value) can be used to detect the contact action value P of the gas density relay body. D20 After all the alarm and / or lockout signal contact action values ​​of the gas density relay body have been detected, the intelligent control unit 7 controls the motor (motor or variable frequency motor) of the pressure regulating mechanism 5 to adjust the piston 51 of the pressure regulating mechanism 5, so that the gas pressure in the gas density relay body gradually increases, and the return value of the alarm and / or lockout contact signal of the gas density relay body is tested. This verification is repeated several times (for example, 2 to 3 times), and then the average value is calculated. This completes the verification of the gas density relay body.

[0084] Furthermore, after all contact signal verification is completed, the intelligent control unit 7 controls the electric control valve 4 to open, connecting the gas density relay with the gas circuit of the electrical equipment, and adjusting the contact signal acquisition unit 6 to the working state. At this time, the intelligent control unit 7 controls the contact signal acquisition unit 6 to energize the control coil of the intermediate relay J1 of the contact signal acquisition unit 6, and its contacts J11 and J12 close. In this way, the contact signal of the gas density relay is connected to the control circuit of the contact signal, and the control circuit of the contact signal of the gas density relay returns to normal operation.

[0085] In this embodiment, the opening and closing of the electric control valve 4 of the gas density relay is controlled by the intelligent control unit 7, which ensures that the gas density relay is communicated with the electrical equipment on the gas path in the working state, so that the gas density relay can safely monitor the gas density of the electrical equipment and enable the electrical equipment to operate safely and reliably; in the calibration state, the gas density relay is not communicated with the electrical equipment on the gas path, and online calibration of the gas density relay will not affect the safe operation of the electrical equipment. This embodiment can realize online calibration of the gas density relay, improves efficiency, reduces operation and maintenance costs, and achieves zero emission of SF6 gas in the whole calibration process, which meets the requirements of environmental protection regulations and is conducive to popularization and application.

[0086] The present invention makes innovations aiming at the high precision requirements of intelligent self-calibrating density relays: the mechanical part consists of a display functional area and a contact signal control functional area. The display functional area is realized by using a Bourdon tube as a pressure measuring element to drive a movement and a pointer for display, thereby realizing full-range display. The contact signal control functional area adopts a bellows as a pressure measuring element to form a bellows assembly mechanism, which greatly improves the vibration resistance. Meanwhile, the lever proportional amplification principle is adopted to amplify the contact signal control and adjustment ratio, so as to realize precise adjustment control and improve the precision of contact signal control; the display function can also be digital.

[0087] The high-precision technology gas density relay of the present invention has a self-calibration function. The intelligent control unit controls the rise and fall of gas pressure of the pressure regulating mechanism, and the lever mechanism causes the micro switch to act, that is, the contact of the density relay acts, so that the online calibration contact signal sampling unit sends a signal to the intelligent control unit, and then the intelligent control unit collects the gas pressure and temperature values when the contact acts through an integrated pressure and temperature sensor, and automatically calculates and converts them into the pressure value corresponding to the gas at 20°C, that is, the density value. This density value is compared with the theoretically set alarm and lockout contact parameter values initially set for the density relay. If the difference meets the precision requirement of the density relay itself, the density relay is qualified, otherwise it is unqualified.

[0088] Meanwhile, regular inspection of SF6 gas density relays on SF6 electrical equipment is a necessary measure to prevent accidents and ensure the safe and reliable operation of SF6 electrical equipment. Innovative transformation of existing gas density relays improves the precision of the density relays, enables them to work reliably for a long time, and enables the gas density relays to complete the online self-calibration function without power outage, thereby completing the regular online non-power-outage calibration of mechanical density relays. The calibration of the density relay does not require maintenance personnel to be present on site, which greatly improves efficiency and reduces costs. Consequently, this high-precision density relay can realize online self-calibration of the gas density relay body, realize that the gas density monitoring of electrical equipment requires no manual maintenance, improves the reliability of the power grid, improves efficiency and reduces costs.

[0089] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0090] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0091] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0092] These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable apparatus for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0093] Specific embodiments have been used to illustrate the principles and implementation methods of this invention. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core ideas of this invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this invention. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A sulfur hexafluoride gas density relay based on a bellows and a Baden tube, characterized in that, The relay includes: mechanical components and remote electronic components; The mechanical components include a front housing, an equipment connection connector, a dial, a display pointer, a control area vent pipe, a display area vent pipe, a dial core assembly, and a pressure regulating mechanism; wherein, the equipment connection connector, dial, display pointer, control area vent pipe, display area vent pipe, dial core assembly, and pressure regulating mechanism are disposed within the front housing; the equipment connection connector is connected to the measured sulfur hexafluoride gas chamber; the display pointer is disposed on the dial; the pressure regulating mechanism is connected to the control area vent pipe and the equipment connection connector; The watch movement assembly includes a bellows, a Baden tube, a push rod, a chassis, a movement, a base, an end seat, a hinge, a connecting rod, a bracket, a meshing spring, a pull rod, a micro switch, a support plate, a bimetallic temperature compensation plate, and an operating arm. One end of the bellows is connected to the chassis, and the other end is connected to the push rod. One end of the Baden tube and one end of the bimetallic temperature compensation plate are both fixed to the end seat, and the other end of the Baden tube is sealed to the base to form a sealed cavity. The sulfur hexafluoride gas to be measured enters the Baden tube through the equipment connection joint and the display area vent pipe. The other end of the bimetallic temperature compensation plate is fixedly connected to the operating arm, and the upper part of the operating arm is connected to the mechanism so that the mechanism drives the display pointer to rotate on the dial; the top rod is connected to one end of the connecting rod; the connecting rod is disposed on the hinge seat, and the other end of the connecting rod is connected to the pull rod; the bracket is fixed on the chassis, and the micro switch is disposed on the bracket; Wherein, one end of the engagement spring is fixed to the chassis, and the other end pulls the pull rod; the support plate is fixedly connected to the pull rod; wherein, when the gas pressure of the gas being measured in the bellows increases or decreases, the top rod increases or decreases accordingly, driving the connecting rod to form a lever structure through the hinge seat; The remote transmission electronic component includes a rear housing, an integrated pressure and temperature sensor, and a remote transmission circuit board; wherein, the integrated pressure and temperature sensor and the remote transmission circuit board are disposed inside the rear housing; the integrated pressure and temperature sensor is connected to the bellows; and the remote transmission circuit board is used for data transmission.

2. The relay according to claim 1, characterized in that, The watch movement assembly also includes a guide seat and a support frame; wherein, the push rod is guided by the support frame and the guide seat as a guiding element, so that the displacement of the push rod is in the vertical direction.

3. The relay according to claim 1, characterized in that, The watch movement assembly also includes a pin for connecting the top rod and the connecting rod.

4. The relay according to claim 1, characterized in that, The watch movement assembly also includes a sleeve and a cover plate; wherein the sleeve, cover plate and chassis form a sealed cavity that encloses the watch, forming a relative cavity.

5. The relay according to claim 1, characterized in that, The mechanical component also includes a three-way connector, the three joints of which are respectively connected to the equipment connection connector, the pressure regulating mechanism, and the control area vent pipe.

6. The relay according to claim 1, characterized in that, The watch core assembly also includes an insulating pad disposed between the micro switch and the bracket.

7. The relay according to claim 1, characterized in that, The watch movement assembly also includes a locking nut, which is disposed at the upper end of the pull rod and is used to fix and lock the support plate to the pull rod.

8. The relay according to claim 1, characterized in that, The watch movement assembly also includes an adjusting screw for adjusting the gap between the support plate and the micro switch.

9. The relay according to claim 1, characterized in that, The remote transmission electronic component also includes a signal sampling unit for receiving the action signal fed back by the micro switch.

10. The relay according to claim 9, characterized in that, The remote transmission electronic component also includes an intelligent control unit, which communicates with the signal sampling unit, the pressure and temperature integrated sensor, and the remote transmission circuit board.

Images