SF6 micro-water density monitoring sensor for GIS (Gas Insulated Switchgear) gas chamber

Abstract

The utility model provides a gas insulated switchgear (GIS) gas chamber sulfur hexafluoride (SF6) micro-water density monitoring sensor, and relates to the technical field of high-voltage electrical equipment state monitoring and sensors. The sensor comprises a sensor main body, an immersion type probe, a micro heating module and a communication module, the sensor body is a sealed shell, and a data processing unit and a power interface are arranged in the sensor body. The immersion type probe penetrates through the bottom of the main body and is fixedly connected with and exposes the pressure, humidity and temperature sensor. The micro-heating module is fixed on the surface of the probe and electrically connected with the humidity sensor. And the data processing unit is integrated with a temperature compensation module and is in signal connection with the pressure and temperature sensor. And the communication module is arranged at the top of the main body, comprises an RS485 interface and is connected with the data processing unit to realize data transmission. The sensor is used for monitoring the micro-water density of SF6 gas in a GIS gas chamber, and solves the technical problem of how to realize high-precision and anti-interference real-time online monitoring of the micro-water density on the premise of not discharging the SF6 gas.

Description

TECHNICAL FIELD

[0001] The utility model relates to high -voltage electrical equipment state monitoring and sensor technical field, specifically, relate to a GIS gas chamber SF6 micro water density monitoring sensor. BACKGROUND

[0002] With the fast development of the intelligentization and high reliability of the power system, the accurate monitoring of the micro water content and density parameters of SF6 gas as the core insulating medium of high -voltage equipment is crucial to the safe operation of equipment. However, the traditional offline detection needs to discharge a large amount of SF6 gas regularly, which not only causes greenhouse effect pollution, but also leads to high operation and maintenance cost, poor real -time performance, and is difficult to meet the real -time sensing and environmental protection double requirements of power grid equipment state, and the industry urgently needs a non -emission type online monitoring technology.

[0003] At present, the mainstream scheme relies on portable dew point meter power failure detection, and realizes micro water measurement through intermittent gas sampling, but there are problems such as long detection period, data lag and gas waste. And the existing online sensor is easily affected by temperature fluctuation, humidity condensation and electromagnetic interference, and lacks self -adaptive compensation mechanism, which leads to the decline of measurement accuracy and frequent calibration, and is difficult to adapt to the continuous monitoring demand under complex working conditions.

[0004] In summary, how to realize high -precision, anti -interference micro water density real -time online monitoring without discharging SF6 gas has become a technical problem to be solved. UTILITY MODEL CONTENTS

[0005] The main purpose of the utility model is to provide a kind of GIS gas chamber SF6 micro water density monitoring sensor, to at least solve the technical problem of how to realize high-precision, anti-interference micro water density real-time online monitoring without discharging SF6 gas, so as to realize the high-precision online monitoring of SF6 gas micro water density, without discharging gas, while ensuring long-term stability and anti-interference ability under complex working conditions.

[0006] In order to achieve the above purpose, the utility model provides a kind of GIS gas chamber SF6 micro water density monitoring sensor, the sensor includes: sensor main body, immersion probe, micro heating module and communication module;

[0007] The sensor main body is a sealed shell, and the data processing unit and power interface are integrated in the sensor main body;

[0008] The immersion probe penetrates through the bottom of the sensor body, is fixedly connected with the sensor body through an integrated sealing mounting structure, and comprises a pressure sensor, a humidity sensor and a temperature sensor, and detection ends of the pressure sensor, the humidity sensor and the temperature sensor are exposed outside the sensor body.

[0009] The micro-heating module is fixed to the surface of the immersion probe and is electrically connected with the humidity sensor.

[0010] The data processing unit is internally integrated with a temperature compensation module which is signal-connected with the pressure sensor and the temperature sensor.

[0011] The communication module is arranged at the top of the sensor body, comprises an RS485 interface, and is connected with the data processing unit through internal lines.

[0012] Specifically, the data processing unit comprises a linear correction unit, an input end of the linear correction unit is signal-connected with the humidity sensor, and an output end of the linear correction unit is connected to the communication module.

[0013] Specifically, the bottom of the sensor body is provided with a threaded connection portion, the outer diameter of the threaded connection portion is M20x1.5, an end face of the threaded connection portion is provided with a sealing groove, and a fluororubber sealing ring is embedded in the sealing groove.

[0014] Specifically, the micro-heating module is a ring-shaped ceramic heating sheet, the inner diameter of the micro-heating module is gap-fitted with the outer diameter of the immersion probe, and the gap distance is 0.1-0.3mm.

[0015] Specifically, the communication module further comprises an anti-interference shielding layer, the anti-interference shielding layer is wrapped on the external lines of the RS485 interface, and the shielding layer has a thickness of 0.5-1.0mm.

[0016] Specifically, the shell of the sensor body is made of 316L stainless steel, the surface of the sensor body is provided with an IP65 protective coating, and the thickness of the IP65 protective coating is 50-80μm.

[0017] Specifically, the perpendicularity deviation of the axis of the immersion probe to the bottom surface of the sensor body is ≤0.1°, and the length of the immersion probe is 30-50mm.

[0018] The utility model provides a kind of GIS gas chamber SF6 micro water density monitoring sensor, the sensor includes sensor main body, immersion probe, micro heating module and communication module.Sensor main body is sealed shell, inside integrated data processing unit and power interface.Immersion probe penetrates sensor main body bottom and fixedly connected, exposed pressure, humidity and temperature sensor, for directly measuring the relevant parameters in GIS gas chamber.Micro heating module is fixed on probe surface, and humidity sensor is electrically connected, for eliminating condensation interference in humidity measurement.Data processing unit is integrated with temperature compensation module, receives the signal of pressure and temperature sensor, and carries out accurate calculation.Communication module is arranged at the top of sensor main body, equipped with RS485 interface, and data processing unit is connected, realizes the transmission and monitoring of data.The sensor can efficiently and accurately monitor the micro water density of GIS gas chamber SF6. BRIEF DESCRIPTION OF DRAWINGS

[0019] The drawings accompanying the specification of this application form a part thereof, serve to provide further understanding of the present application, and together with the description of the exemplary embodiments of the present application, serve to explain the present application, and do not constitute improper limitations on the present application. In the drawings:

[0020] Figure 1 It is according to the longitudinal sectional schematic view of a kind of GIS gas chamber SF6 micro water density monitoring sensor of optional embodiment of the utility model;

[0021] 10, sensor main body;20, immersion probe;30, micro heating module;50, communication module;11, data processing unit;12, power interface;21, pressure sensor;22, humidity sensor;23, temperature sensor;111, linear correction unit;112, temperature compensation module;13, threaded connection part;14, fluorine rubber sealing ring;15, IP65 protective coating;51, RS485 interface;52, anti-interference shield layer. DETAILED DESCRIPTION

[0022] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.The present application will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0023] According to the GIS gas chamber SF6 micro water density monitoring sensor provided by the utility model embodiment, Figure 1The utility model provides a kind of GIS gas chamber SF6 micro water density monitoring sensor, the sensor includes: sensor main body 10, immersion probe 20, micro heating module 30 and communication module 50;The sensor main body 10 is sealed shell, the sensor main body 10 inside integrated with data processing unit 11 and power interface 12;The immersion probe 20 penetrates the bottom of the sensor main body 10, the immersion probe 20 is fixedly connected with the sensor main body 10 by integrated sealing mounting structure, the immersion probe 20 includes pressure sensor 21, humidity sensor 22 and temperature sensor 23, and the detection end of the pressure sensor 21, the humidity sensor 22 and the temperature sensor 23 is exposed outside the sensor main body 10;The micro heating module 30 is fixed on the surface of the immersion probe 20, and the micro heating module 30 is electrically connected with humidity sensor 22;The data processing unit 11 inside integrated temperature compensation module 112, the temperature compensation module 112 is signal connected with the pressure sensor 21 and the temperature sensor 23;The communication module 50 is arranged on the top of the sensor main body 10, and the communication module 50 includes RS485 interface 51, and the communication module 50 is connected with the data processing unit 11 by internal circuit.Specifically, the GIS gas chamber SF6 micro water density monitoring sensor of the utility model includes sensor main body 10, immersion probe 20, micro heating module 30 and communication module 50, sensor main body 10 is sealed shell and inside integrated data processing unit 11 and power interface 12, power interface 12 is connected external power cord through welding to provide stable power supply, immersion probe 20 is cylindrical structure and penetrates sensor main body 10 bottom, immersion probe 20 is fixed with sensor main body 10 through threaded connection 13, the outer diameter of threaded connection 13 is M20x1.5 and the end face is provided with sealing groove, fluorine rubber sealing ring 14 is embedded in sealing groove to form airtight seal to prevent SF6 gas leakage, the axis of immersion probe 20 and the perpendicularity deviation of sensor main body 10 bottom surface is less than or equal to 0.1 ° to guarantee the installation alignment accuracy of probe and gas chamber, the detection end of immersion probe 20 is exposed outside sensor main body 10 and includes pressure sensor 21, humidity sensor 22 and temperature sensor 23, the detection end of pressure sensor 21, the detection end of humidity sensor 22 and the detection end of temperature sensor 23 are flush with the surface of immersion probe 20 to directly contact SF6 gas and realize multi-parameter synchronous acquisition, micro heating module 30 is annular ceramic heating sheet, the inner diameter of micro heating module 30 and the outer diameter of immersion probe 20 are gap fit and the gap distance is 0.1-0.3mm to avoid structure deformation caused by thermal expansion, micro heating module 30 is sleeved on the surface of immersion probe 20 and is fixed through mechanical buckle to maintain the position stability of heating sheet, the electrode of micro heating module 30 is connected with the power supply pin of humidity sensor 22 through copper wire to provide local heating to eliminate the condensation interference on the surface of humidity sensor 22, data processing unit 11 is integrated inside sensor main body 10 and is connected with pressure sensor 21, humidity sensor 22 and temperature sensor 23 through internal circuit to receive original detection signal in real time, temperature compensation module 112 is arranged inside data processing unit 11, temperature compensation module 112 receives the pressure signal output by pressure sensor 21 and the temperature signal output by temperature sensor 23, temperature compensation module 112 dynamically corrects the humidity data of humidity sensor 22 based on the pressure signal and the temperature signal through table lookup method to eliminate the influence of temperature drift on micro water density calculation, communication module 50 is arranged on the top of sensor main body 10 and is connected with data processing unit 11 through internal circuit to transmit the corrected monitoring data, communication module 50 includes RS485 interface 51, RS485 interface 51 transmits the corrected humidity data, pressure data and temperature data to external monitoring system through Modbus protocol to realize the high-precision online monitoring of SF6 gas micro water density, the shell material of sensor main body 10 is 316L stainless steel to resist long-term corrosion of SF6 gas and prolong the service life, the sensor solves the technical problem of how to realize high-precision, anti-interference micro water density real-time online monitoring without discharging SF6 gas.Thus, the high-precision on-line monitoring of the SF6 gas micro-water density is realized, the gas is not needed to be discharged, and the long-term stability and anti-interference ability under complex working conditions are ensured.

[0024] Specifically, the data processing unit 11 comprises a linear correction unit 111, an input end of the linear correction unit 111 is connected with the humidity sensor 22 in signal, and an output end of the linear correction unit 111 is connected to the communication module 50. In the GIS gas chamber SF6 micro-water density monitoring sensor of the utility model, the data processing unit 11 comprises a linear correction unit 111, the input end of the linear correction unit 111 is connected with the output pin of the humidity sensor 22 through internal signal line to receive the original humidity analog signal output by the humidity sensor 22, the output end of the linear correction unit 111 is connected with the input port of the communication module 50 through internal circuit to transmit the corrected digital humidity signal, the linear correction unit 111 is integrated on the circuit board of the data processing unit 11 and is fixed by welding to ensure the stability of signal transmission, the linear correction unit 111 is built-in least square method linear fitting algorithm, the least square method linear fitting algorithm establishes the linear mapping relationship between voltage value and humidity value based on the calibration data of the humidity sensor 22, the nonlinear analog signal output by the humidity sensor 22 is converted into linear digital signal to eliminate the sensor nonlinear error, and the corrected digital humidity signal is transmitted to the external monitoring system through the RS485 interface 51 of the communication module 50, the RS485 interface 51 adopts Modbus protocol encapsulation data format to adapt to industrial monitoring equipment, so that the high-precision on-line monitoring of the SF6 micro-water density is realized.

[0025] Specifically, the bottom of the sensor main body 10 is provided with a threaded connection part 13, the outer diameter of the threaded connection part 13 is M20x1.5, and the end face of the threaded connection part 13 is provided with a sealing groove, and a fluorine rubber sealing ring 14 is embedded in the sealing groove. Specifically, in the GIS gas chamber SF6 micro-water density monitoring sensor of the utility model, the bottom of the sensor main body 10 is provided with a threaded connection part 13, the outer diameter of the threaded connection part 13 is M20x1.5 to adapt to the standard gas chamber interface to realize rapid installation, the end face of the threaded connection part 13 is provided with a sealing groove with a rectangular cross section, the width of the sealing groove is 2mm, and the depth is 1.5mm, the fluorine rubber sealing ring 14 is embedded in the sealing groove to fill the gap by compression deformation to form a seal, the cross-sectional diameter of the fluorine rubber sealing ring 14 is 2mm, and the compression amount after installation is 0.5mm to provide elastic sealing force, the threaded connection part 13 is engaged with the internal thread of the mounting hole of the GIS gas chamber through the external thread to fix the sensor main body 10, the fluorine rubber sealing ring 14 is compressed between the sealing groove and the end face of the gas chamber after the threaded connection to prevent SF6 gas leakage, and the machining precision of the threaded connection part 13 is 6H / 6g level to ensure the reliability and air tightness of the threaded connection.

[0026] Specifically, the micro-heating module 30 is a ring-shaped ceramic heating sheet, and the inner diameter of the micro-heating module 30 is gap-fitted with the outer diameter of the immersion probe 20 with a gap distance of 0.1-0.3 mm. Specifically, in the GIS gas chamber SF6 micro-water density monitoring sensor of the utility model, the micro-heating module 30 is a ring-shaped ceramic heating sheet, the material of the micro-heating module 30 is alumina ceramic and the surface is coated with nichrome resistance wire to provide uniform heating, the inner diameter of the micro-heating module 30 is gap-fitted with the outer diameter of the immersion probe 20 with a gap distance of 0.1-0.3 mm to allow thermal expansion and avoid thermal stress deformation caused by direct contact between the ceramic heating sheet and the immersion probe 20, the micro-heating module 30 is fixed to the outer surface of the immersion probe 20 by epoxy resin adhesive to maintain the stability of the gap distance, the nichrome resistance wire of the micro-heating module 30 is connected in parallel with the power supply circuit of the humidity sensor 22 through copper wires to synchronously control the heating power, the ring-shaped structure of the micro-heating module 30 completely wraps the humidity sensor 22 detection end area of the immersion probe 20 to locally heat and prevent moisture condensation from interfering with the detection accuracy, the power supply voltage of the micro-heating module 30 is 5V DC and the heating temperature is adjusted to 40-50℃ through pulse width modulation technology to balance the power consumption and condensation prevention effect, and the alumina ceramic material of the micro-heating module 30 has high thermal conductivity to quickly transfer heat to the surface of the humidity sensor 22 and keep the temperature evenly distributed.

[0027] Specifically, the communication module 50 further comprises an anti-interference shielding layer 52, which is coated on the external line of the RS485 interface 51, and the thickness of the shielding layer is 0.5-1.0 mm. In the GIS gas chamber SF6 micro water density monitoring sensor, the communication module 50 comprises the RS485 interface 51 and the anti-interference shielding layer 52, the anti-interference shielding layer 52 is a copper foil layer with a thickness of 0.5-1.0 mm, the anti-interference shielding layer 52 is coated on the outer surface of the external signal line of the RS485 interface 51 by a hot pressing process to completely cover the exposed part of the signal line, the edge of the anti-interference shielding layer 52 overlaps the insulating layer of the signal line by 1-2 mm to prevent the copper foil layer from being buckled, the anti-interference shielding layer 52 is connected with the metal shell of the sensor main body 10 by welding to form an electromagnetic shielding grounding loop, the signal line core wire of the RS485 interface 51 is connected with the output port of the data processing unit 11 by soldering to transmit the corrected humidity, pressure and temperature data, the signal line core wire of the RS485 interface 51 is a twisted pair structure to suppress common mode interference, the polyester film insulating layer is filled between the copper foil layer of the anti-interference shielding layer 52 and the twisted pair core wire to isolate the conductor contact, the RS485 interface 51 encapsulates the data into a fixed format data frame through the Modbus protocol and transmits the data to the external monitoring equipment through differential signal transmission, the shielding effectiveness of the anti-interference shielding layer 52 reaches more than 30 dB to block the high-frequency electromagnetic interference generated during the operation of the GIS equipment, and the thickness of the anti-interference shielding layer 52 is 0.5-1.0 mm, which guarantees the flexibility and meets the mechanical strength requirements.

[0028] Specifically, the shell material of the sensor body 10 is 316L stainless steel, the surface of the sensor body 10 is provided with an IP65 protective coating 15, and the thickness of the IP65 protective coating 15 is 50-80 μm. In the GIS gas chamber SF6 micro water density monitoring sensor of the utility model, the shell material of the sensor body 10 is 316L stainless steel to resist the chemical corrosion of SF6 gas and the mechanical stress under high pressure environment, the shell of the sensor body 10 is processed into a cylindrical structure through a cold rolling forming process and is welded and sealed through argon arc welding to ensure the air tightness, the surface of the sensor body 10 is coated with an IP65 protective coating 15 through an electrostatic spraying process, the material of the IP65 protective coating 15 is polyurethane paint and the thickness is 50-80 μm to form a uniform covering layer, the IP65 protective coating 15 is coated twice and the single spraying thickness is 25-40 μm to control the coating thickness error within ± 5 μm, the spraying range of the IP65 protective coating 15 covers the outer surface of the sensor body 10 and the end face of the threaded connection part 13 to comprehensively protect the external moisture and dust from entering, the IP65 protective coating 15 is cured at 80-100 DEG C hot air for 30 minutes after coating to enhance the coating adhesion and wear resistance, the 316L stainless steel surface of the sensor body 10 is sandblasted before spraying the IP65 protective coating 15 to improve the coating bonding strength with the texture of roughness Ra3.2, and the thickness of the IP65 protective coating 15 is 50-80 μm to form a continuous and pore-free protective layer after curing to block the moisture penetration and adapt to the temperature fluctuation of-40 DEG C to 80 DEG C.

[0029] Specifically, the axis of the immersion probe 20 is perpendicular to the bottom surface of the sensor body 10 with a deviation of ≤0.1°, and the length of the immersion probe 20 is 30-50 mm. In the GIS gas chamber SF6 micro water density monitoring sensor of the utility model, the axis of the immersion probe 20 is perpendicular to the bottom surface of the sensor body 10 with a deviation of ≤0.1° to control the vertical alignment of the probe and the gas chamber flange installation plane through the machining precision of the integrated sealing installation structure, the immersion probe 20 is a cylindrical structure and the length is 30-50 mm to adapt to the installation depth of the gas chamber interface, the immersion probe 20 is fixedly connected with the bottom of the sensor body 10 through the integrated sealing installation structure, the integrated sealing installation structure includes the interference fit of the root annular boss of the immersion probe 20 and the annular groove at the bottom of the sensor body 10 and is sealed through laser welding, the detection end of the immersion probe 20 is exposed outside the sensor body 10 and extends for 30-50 mm to directly contact the SF6 gas in the gas chamber, the axis of the immersion probe 20 is calibrated through a three-coordinate measuring machine and then uses a positioning pin to lock the installation angle of the sensor body 10 and the gas chamber interface, and the length of the immersion probe 20 is 30-50 mm to adjust to the target size through turning machining according to the thickness of the gas chamber flange to match different working conditions.

[0030] The above merely describes preferred embodiments of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A GIS gas chamber SF6 micro-water density monitoring sensor, characterized in that, The sensor body (10), the immersion probe (20), the micro-heating module (30) and the communication module (50) are included. The sensor body (10) is a sealed shell, and a data processing unit (11) and a power supply interface (12) are integrated inside the sensor body (10). The immersion probe (20) penetrates the bottom of the sensor body (10) and is fixedly connected with the sensor body (10) through an integrated sealing mounting structure. The micro-heating module (30) is fixed to the surface of the immersion probe (20) and is electrically connected with the humidity sensor (22). The data processing unit (11) is internally integrated with a temperature compensation module (112) which is signal connected with the pressure sensor (21) and the temperature sensor (23). The communication module (50) is arranged on the top of the sensor body (10) and includes an RS485 interface (51) which is connected with the data processing unit (11) through internal lines.

2. The GIS gas chamber SF6 micro-water density monitoring sensor according to claim 1, wherein the data processing unit (11) includes a linear correction unit (111) which is signal connected with the humidity sensor (22) at the input end and connected with the communication module (50) at the output end.

3. The GIS gas chamber SF6 micro-water density monitoring sensor according to claim 1, wherein the bottom of the sensor body (10) is provided with a threaded connection part (13) which has an outer diameter of M20x1.5 and an end face provided with a sealing groove in which a fluororubber sealing ring (14) is embedded.

4. The GIS gas chamber SF6 micro-water density monitoring sensor according to claim 1, wherein the micro-heating module (30) is a ring-shaped ceramic heating sheet which has an inner diameter matched with the outer diameter of the immersion probe (20) with a gap distance of 0.1-0.3mm.

5. The GIS gas chamber SF6 micro-water density monitoring sensor according to claim 1, wherein the communication module (50) further includes an anti-interference shielding layer (52) which is coated on the external lines of the RS485 interface (51) and has a thickness of 0.5-1.0mm.

6. The GIS gas chamber SF6 micro-water density monitoring sensor according to claim 1, wherein ​ ​ ​ ​ ​ The shell material of the sensor body (10) is 316L stainless steel, and the surface of the sensor body (10) is provided with an IP65 protective coating (15), and the thickness of the IP65 protective coating (15) is 50-80μm.

7. The GIS gas chamber SF6 micro-water density monitoring sensor according to claim 1, characterized in that: The axis of the immersion probe (20) is perpendicular to the bottom surface of the sensor body (10) with a perpendicularity deviation of ≤0.1°, and the length of the immersion probe (20) is 30-50mm.

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