A gas density relay with online self-checking function and a checking method thereof

Abstract

This application provides a gas density relay with online self-calibration function and its calibration method. The gas density relay includes a gas density relay body, a first pressure sensor, a second pressure sensor, a temperature sensor, a pressure regulating mechanism, an online calibration contact signal sampling unit, and an intelligent control unit. The gas density relay body includes a housing, a first sealed gas chamber connected to an insulating gas chamber of electrical equipment within the housing, and a second sealed gas chamber filled with standard compensation gas. The first pressure sensor is connected to the first density gas chamber, and the second pressure sensor is connected to the second sealed gas chamber. The pressure regulating mechanism is connected to the second sealed gas chamber. The intelligent control unit controls the pressure regulating mechanism to adjust the pressure rise and fall of the second sealed gas chamber, causing the gas density relay body to activate its contacts and complete the calibration of the gas density relay. This eliminates the need for maintenance personnel to perform on-site calibration, improving work efficiency and reducing the sealing requirements of the power grid.

Description

Technical Field

[0001] This invention relates to the field of power technology, specifically to a gas density relay with online self-calibration function applied to high-voltage and medium-voltage electrical equipment, and its calibration method. Background Technology

[0002] With the development of unmanned substations towards networking and digitalization, and the increasing demands for remote control and telemetry, online monitoring of the gas density and moisture content of SF6 electrical equipment has significant practical importance. As China's smart grid continues to develop rapidly, intelligent high-voltage electrical equipment, as a crucial component and key node of smart substations, plays a vital role in the safety of the smart grid. Most high-voltage electrical equipment is currently SF6 gas-insulated; a decrease in gas density (such as due to leakage) will severely affect the electrical performance of the equipment, posing a serious threat to safe operation. Online monitoring of gas density values ​​in SF6 high-voltage electrical equipment is now very common, leading to the rapid development of gas density monitoring systems (gas density relays). Current gas density monitoring systems (gas density relays) are basically: 1) using remote-type SF6 gas density relays to collect and upload density, pressure, and temperature data for online gas density monitoring; 2) using gas density transmitters to collect and upload density, pressure, and temperature data for online gas density monitoring. The SF6 gas density relay is a core and key component.

[0003] Regular inspection of gas density relays on electrical equipment is a necessary measure to prevent potential accidents and ensure the safe and reliable operation of electrical equipment. Both the "Electric Power Preventive Testing Regulations" and the "Twenty-Five Key Requirements for Preventing Major Accidents in Power Production" require regular calibration of gas density relays. In practice, regular calibration of gas density relays is one of the essential means to ensure the safe and reliable operation of power equipment. Therefore, the calibration of gas density relays is now highly valued and widespread in the power system, and has been implemented by various power supply companies, power plants, and large industrial and mining enterprises. However, power supply companies, power plants, and large industrial and mining enterprises need to equip themselves with testing personnel, equipment vehicles, and high-value SF6 gas to complete on-site calibration and testing of gas density relays. Including the business losses due to power outages during testing, a rough calculation shows that the annual testing cost for each high-voltage switch station is approximately tens of thousands to hundreds of thousands of yuan. Furthermore, improper on-site calibration by testing personnel can also pose safety hazards. Therefore, it is essential to innovate existing gas density self-calibrating gas density relays, especially online gas density self-calibrating gas density relays or systems, so that the gas density relays or monitoring systems composed of them for online gas density monitoring also have the calibration function of gas density relays, thereby completing the periodic calibration of (mechanical) gas density relays without the need for maintenance personnel to go to the site, thus improving work efficiency and reducing operation and maintenance costs. Summary of the Invention

[0004] The purpose of this invention is to provide a gas density relay with online self-calibration function and its calibration method, so as to solve the problems mentioned in the above technical background.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] The first aspect of this application provides a gas density relay with online self-calibration function, including: a gas density relay body, a first pressure sensor, a second pressure sensor, a temperature sensor, a pressure regulating mechanism, an online calibration contact signal sampling unit, and an intelligent control unit;

[0007] The gas density relay body includes: a housing, a first sealed gas chamber connected to the insulating gas chamber of an electrical device within the housing, and a second sealed gas chamber filled with a standard compensation gas; the second sealed gas chamber is filled with a gas having a density value of P. 20BC Standard compensating gas;

[0008] The first pressure sensor is connected to the first sealed gas chamber of the gas density relay body;

[0009] The second pressure sensor is connected to the second sealed gas chamber of the gas density relay body;

[0010] The pressure regulating mechanism is disposed outside the gas density relay body. The gas passage of the pressure regulating mechanism is connected to the second sealed gas chamber and is configured to regulate the gas pressure of the second sealed gas chamber, so that the gas density relay body generates a contact signal action.

[0011] The online verification contact signal sampling unit is connected to the signal generator of the gas density relay body and is configured to sample the contact signal when the gas density relay body generates a contact signal action.

[0012] The intelligent control unit is connected to the pressure regulating mechanism, the first pressure sensor, the second pressure sensor, the temperature sensor, and the online verification contact signal sampling unit, and is configured to control the pressure regulating mechanism, acquire pressure and temperature values, and / or acquire gas density values, and detect the contact signal action value and / or contact signal return value of the gas density relay body.

[0013] The contact signals include alarm and / or interlock.

[0014] The second aspect of this application provides a gas density monitoring device with online self-calibration function, including: a gas density relay body, a first pressure sensor, a second pressure sensor, a temperature sensor, a pressure regulating mechanism, an online calibration contact signal sampling unit, and an intelligent control unit;

[0015] The gas density relay body includes: a housing, a first sealed gas chamber connected to the insulating gas chamber of an electrical device within the housing, and a second sealed gas chamber filled with a standard compensation gas; the second sealed gas chamber is filled with a gas having a density value of P. 20BC Standard compensating gas;

[0016] The first pressure sensor is connected to the first sealed gas chamber of the gas density relay body;

[0017] The second pressure sensor is connected to the second sealed gas chamber of the gas density relay body;

[0018] The pressure regulating mechanism is disposed outside the gas density relay body. The gas passage of the pressure regulating mechanism is connected to the second sealed gas chamber and is configured to regulate the gas pressure of the second sealed gas chamber, so that the gas density relay body generates a contact signal action.

[0019] The online verification contact signal sampling unit is connected to the signal generator of the gas density relay body and is configured to sample the contact signal when the gas density relay body generates a contact signal action.

[0020] The intelligent control unit is connected to the pressure regulating mechanism, the first pressure sensor, the second pressure sensor, the temperature sensor, and the online verification contact signal sampling unit, and is configured to control the pressure regulating mechanism, acquire pressure and temperature values, and / or acquire gas density values, and detect the contact signal action value and / or contact signal return value of the gas density relay body.

[0021] The contact signals include alarm and / or interlock.

[0022] Preferably, the gas density relay body includes: a housing, a first bellows, a second bellows, a signal generator, and a signal conditioning mechanism; wherein, the first open end of the first bellows is fixed to the inner wall of the housing, the second open end of the first bellows is sealed to a first sealing element, the inner wall of the first bellows, the first sealing element, and the inner wall of the housing together form a first sealed gas chamber, and the first sealed gas chamber is provided with an interface communicating with the insulating gas of electrical equipment; the first open end of the second bellows is sealed to the first sealing element, the second open port of the second bellows is connected to the inner wall of the housing through a second sealing element, and the outer wall of the first bellows, the first sealing element, the outer wall of the second bellows, the second sealing element, and the inner wall of the housing together form a second sealed gas chamber; the signal conditioning mechanism is connected to the first sealing element, and the signal generator is provided corresponding to the signal conditioning mechanism.

[0023] The positions of the first and second sealed air chambers can be interchanged; for example, the inner wall of the first bellows, the first seal, and the inner wall of the outer shell together form the second sealed air chamber; the outer wall of the first bellows, the first seal, the outer wall of the second bellows, the second seal, and the inner wall of the outer shell together form the first sealed air chamber, and the first sealed air chamber is provided with an interface for communication with the insulating gas of the electrical equipment.

[0024] More preferably, the outer diameter of the first bellows is larger than the outer diameter of the second bellows.

[0025] More preferably, the signal adjustment mechanism includes a movable rod, one end of which extends into the second bellows and is connected to the first seal, and is displaced as the first bellows deforms; the other end of the movable rod extends out of the second bellows and is fixedly connected to a crossbar, the crossbar being provided with an adjusting screw, the adjusting screw being used to actuate the signal generator under the pushing force of the movable rod.

[0026] More preferably, the signal generator includes a micro switch or a magnetically assisted electrical contact, and the gas density relay body outputs a contact signal through the signal generator.

[0027] Preferably, the intelligent control unit acquires the gas density values ​​collected by the first pressure sensor and temperature sensor; or, the intelligent control unit acquires the pressure and temperature values ​​collected by the first pressure sensor and temperature sensor to complete the online monitoring of the gas density of the monitored electrical equipment by the gas density relay.

[0028] Preferably, the intelligent control unit acquires the gas density value P collected by the second pressure sensor and temperature sensor. 20BCS Alternatively, the intelligent control unit acquires the pressure value P collected by the second pressure sensor. BCS Based on the temperature value T collected by the temperature sensor, the gas density value P of the second sealed gas chamber is determined. 20BCS Online monitoring; or,

[0029] The intelligent control unit acquires the gas density value P collected by the second pressure sensor and temperature sensor. 20BCS Alternatively, the intelligent control unit acquires the pressure value collected by the second pressure sensor and the temperature value collected by the temperature sensor to obtain the gas density value P of the second sealed gas chamber. 20BCS This indirectly verifies the action value of the contact signal of the gas density relay body; or,

[0030] The intelligent control unit acquires the gas density value P collected by the second pressure sensor and temperature sensor. 20BCS Alternatively, the intelligent control unit acquires the pressure value collected by the second pressure sensor and the temperature value collected by the temperature sensor to obtain the gas density value P of the second sealed gas chamber. 20BCS When |P 20BC -P 20BCS | When the set threshold is exceeded, an alarm signal is issued.

[0031] More preferably, the pressure regulating mechanism is controlled by the intelligent control unit, causing the gas density relay body to actuate its contacts. This contact actuation is transmitted to the intelligent control unit via an online verification contact signal sampling unit, enabling the intelligent control unit to detect the actuation of the gas density relay body; or...

[0032] The intelligent control unit controls the pressure regulating mechanism, causing the gas density relay body to activate its contacts. The contact activation is transmitted to the intelligent control unit through the online verification contact signal sampling unit. The intelligent control unit can detect the contact activation of the gas density relay body and the gas density value of the second sealed gas chamber when the contact activation occurs, thus completing the direct or indirect verification of the contact signal activation value of the gas density relay body.

[0033] Preferably, the gas density relay or gas density monitoring device further includes a valve, one end of which is connected to the gas path of the pressure regulating mechanism, and the other end of which is connected to the second sealed gas chamber; preferably, the valve is also connected to the intelligent control unit and is closed or opened under the control of the intelligent control unit.

[0034] More preferably, the valve is an electric valve, and / or a solenoid valve, or a piezoelectric valve, or a temperature-controlled valve, or a novel valve made of smart memory material that is opened or closed by electric heating.

[0035] More preferably, during verification, the valve is in the open state; during non-verification, the valve is in the closed state.

[0036] Preferably, the pressure regulating mechanism is sealed within a cavity or housing.

[0037] Preferably, the pressure regulating mechanism is a sealed air chamber, with a heating element and / or a cooling element provided outside or inside the sealed air chamber. By heating the heating element and / or cooling it through the cooling element, the temperature of the gas inside the sealed air chamber changes, thereby completing the pressure rise and fall of the second sealed air chamber; or,

[0038] The pressure regulating mechanism is a cavity with one open end, the other end of which is connected to the second sealed air chamber. A piston is located within the cavity, one end of which is connected to an adjusting rod. The outer end of the adjusting rod is connected to a driving component. The other end of the piston extends into the opening and is in sealing contact with the inner wall of the cavity. The driving component drives the adjusting rod, thereby moving the piston within the cavity. Alternatively...

[0039] The pressure regulating mechanism is a sealed air chamber. Inside the sealed air chamber is a piston that is in sealed contact with the inner wall of the sealed air chamber. Outside the sealed air chamber is a driving component that pushes the piston to move within the chamber via electromagnetic force; or...

[0040] The pressure regulating mechanism is an airbag connected at one end to a driving component. The airbag changes volume under the drive of the driving component, and the airbag is connected to the second sealed air chamber; or...

[0041] The pressure regulating mechanism is a bellows, one end of which is connected to the second sealing air chamber, and the other end of which extends and retracts under the drive of the driving component; or,

[0042] The pressure regulating mechanism is a vent valve, which is a solenoid valve or an electric valve, or a vent valve that is activated by electricity or pneumatic means; or,

[0043] The pressure regulating mechanism is a compressor; or...

[0044] The pressure regulating mechanism is a pump, which includes one of the following: a pressure-generating pump, a booster pump, an electric air pump, and an electromagnetic air pump; or...

[0045] The pressure regulating mechanism is a pressure boosting valve;

[0046] The driving component includes one of the following: a magnetic force, a motor, a reciprocating motion mechanism, a Carnot cycle mechanism, a magnetic coupling thrust mechanism, a heating thrust mechanism, an electric heating thrust mechanism, a chemical reaction thrust mechanism, and a pneumatic component.

[0047] More preferably, when the pressure regulating mechanism is a sealed air chamber, the pressure regulating mechanism further includes a heat insulation element, which is disposed outside the sealed air chamber.

[0048] Preferably, the gas density relay body and the first pressure sensor are an integrated structure; or, the gas density relay body, the first pressure sensor, and the temperature sensor are an integrated remote gas density relay.

[0049] Preferably, the first pressure sensor and temperature sensor are integrated into one unit; or, the first pressure sensor and temperature sensor are integrated into a gas density transmitter; preferably, the online verification contact signal sampling unit and the intelligent control unit are disposed on the gas density transmitter.

[0050] Preferably, the online verification contact signal sampling unit and the intelligent control unit are arranged together; preferably, the online verification contact signal sampling unit and the intelligent control unit are sealed in a cavity or housing.

[0051] Preferably, the first pressure sensor includes at least one pressure sensor; or, the first pressure sensor is a gas density transmitter composed of a pressure sensor and a temperature sensor; or, the first pressure sensor is a density detection sensor using quartz tuning fork technology.

[0052] Preferably, the first pressure sensor is installed in the gas path of the gas density relay body; the temperature sensor is installed in or outside the gas path of the gas density relay body, or inside or outside the gas density relay body.

[0053] Preferably, the gas density relay body has a density comparison value output signal, which is connected to the intelligent control unit; or, the gas density relay body has a pressure comparison value output signal, which is connected to the intelligent control unit.

[0054] Preferably, the online verification contact signal sampling unit includes an isolation sampling element, which is controlled by the gas density relay body, a pressure regulating mechanism, or an intelligent control unit. In the non-verification state, the contact signals of the online verification contact signal sampling unit and the gas density relay body are relatively isolated in the circuit. In the verification state, the online verification contact signal sampling unit cuts off the contact signal control circuit of the gas density relay body and connects the contacts of the gas density relay body to the intelligent control unit. The isolation sampling element includes one of the following: a limit switch, a micro switch, a button, an electric switch, a displacement switch, an electromagnetic relay, an optocoupler, or a silicon controlled rectifier (SCR).

[0055] Preferably, the online verification contact signal sampling unit samples the contact signals of the gas density relay body in a manner that satisfies the following: the online verification contact signal sampling unit has at least two independent sets of sampling contacts, which can simultaneously and automatically complete the verification of at least two contacts, and can continuously measure without changing or reselecting contacts; wherein, the contacts include, but are not limited to, one of the following: alarm contacts, alarm contacts + interlock contacts, alarm contacts + interlock contacts 1 + interlock contacts 2, and alarm contacts + interlock contacts + overpressure contacts.

[0056] Preferably, the online verification contact signal sampling unit applies a test voltage of not less than 24V to the contact signal action value or switching value of the gas density relay body, that is, during verification, a voltage of not less than 24V is applied between the corresponding terminals of the contact signal.

[0057] Preferably, the gas density relay or gas density monitoring device further includes a multi-port connector, with the gas density relay body and the first pressure sensor mounted on the multi-port connector; or,

[0058] The pressure regulating mechanism is fixed to the multi-port connector; or...

[0059] The gas density relay body, the first pressure sensor, and the pressure regulating mechanism are mounted on the multi-port connector; or...

[0060] The online verification contact signal sampling unit, intelligent control unit, and temperature sensor are installed on the multi-port connector.

[0061] Preferably, the gas density relay or gas density monitoring device further includes a micro-water sensor connected to the gas density relay body and the intelligent control unit, and / or a decomposition product sensor connected to the gas density relay body and the intelligent control unit, respectively.

[0062] Preferably, the online calibration of the gas density relay is completed by comprising at least two gas density relay bodies, at least two first pressure sensors, at least two second pressure sensors, at least two pressure regulating mechanisms, at least two online calibration contact signal sampling units, a smart control unit, and a temperature sensor; or,

[0063] The system comprises at least two gas density relay bodies, at least two first pressure sensors, at least two second pressure sensors, at least two pressure regulating mechanisms, at least two temperature sensors, at least two online verification contact signal sampling units, and an intelligent control unit to complete the online verification of the gas density relays.

[0064] Preferably, the first pressure sensor or the second pressure sensor can be an absolute pressure sensor, a relative pressure sensor, or both an absolute pressure sensor and a relative pressure sensor; it can be a diffused silicon pressure sensor, a MEMS pressure sensor, a chip-type pressure sensor, a coil-inductive pressure sensor (such as a pressure sensor with a Baden tube and an induction coil), or a resistive pressure sensor (such as a pressure sensor with a Baden tube and a slide wire resistor); it can be an analog pressure sensor or a digital pressure sensor.

[0065] Preferably, the temperature sensor can be a thermocouple, a thermistor, or a semiconductor type; it can be a contact type or a non-contact type; it can be a resistance temperature detector (RTD) or a thermocouple.

[0066] Preferably, the electrical equipment includes SF6 gas electrical equipment, SF6 mixed gas electrical equipment, environmentally friendly gas electrical equipment, or other insulating gas electrical equipment.

[0067] Specifically, the electrical equipment includes GIS, GIL, PASS, circuit breakers, current transformers, voltage transformers, transformers, gas-insulated switchgear, and ring main units.

[0068] Preferably, the intelligent control unit is based on the embedded algorithm and control program of the microprocessor embedded system, which automatically controls the entire verification process, including all peripherals, logic and input / output.

[0069] More preferably, the intelligent control unit is based on embedded algorithms and control programs of general-purpose computers, industrial control computers, ARM chips, AI chips, CPUs, MCUs, FPGAs, PLCs, industrial control motherboards, embedded main control boards, etc., to automatically control the entire verification process, including all peripherals, logic and input / output.

[0070] Preferably, the intelligent control unit has an electrical interface, which performs test data storage, and / or test data export, and / or test data printing, and / or data communication with a host computer, and / or inputs analog and digital information.

[0071] Preferably, the gas density relay (or monitoring device) supports the input of basic information of the gas density relay (or monitoring device), which includes one or more of the following: serial number, accuracy requirements, rated parameters, manufacturer, and operating location.

[0072] Preferably, the intelligent control unit further includes a communication module for transmitting test data and / or verification results over long distances.

[0073] More preferably, the communication module uses wired or wireless communication.

[0074] Furthermore, the wired communication method includes one or more of the following: RS232 bus, RS422 bus, RS485 bus, CAN-BUS bus, 4-20mA, HART, IIC, SPI, Wire, coaxial cable, PLC power line carrier, and cable.

[0075] Furthermore, the wireless communication method includes one or more of NB-IoT, 2G / 3G / 4G / 5G, WIFI, Bluetooth, LoRa, LoRawan, Zigbee, infrared, ultrasound, sound waves, satellite, light waves, quantum communication, and sonar.

[0076] Preferably, the intelligent control unit is further provided with a clock, which is configured to periodically set the calibration time of the gas density relay, or record the test time, or record the event time.

[0077] Preferably, the intelligent control unit is controlled through on-site control and / or through background control.

[0078] More preferably, the gas density relay or gas density monitoring device performs online verification of the gas density relay according to the settings or instructions of the background system; or,

[0079] The online calibration of the gas density relay is completed according to the set calibration time.

[0080] Preferably, the gas density relay or gas density monitoring device further includes: a display interface for human-machine interaction, connected to the intelligent control unit, which displays the current verification data in real time and / or supports data input.

[0081] Preferably, the gas density relay or gas density monitoring device further includes a camera for monitoring.

[0082] Preferably, the gas density relay body or gas density monitoring device further includes a contact resistance detection unit; the contact resistance detection unit is connected to the contact signal or directly connected to the signal generator; under the control of the online verification contact signal sampling unit, the contact signal of the gas density relay body is isolated from its control circuit, and when the contact signal is activated, and / or when a command to detect the contact resistance of the contact is received, the contact resistance detection unit can detect the contact resistance value of the gas density relay body.

[0083] Preferably, the gas density relay body or gas density monitoring device further includes an insulation resistance detection unit; the insulation resistance detection unit is connected to the contact signal or directly connected to the signal generator; under the control of the online verification contact signal sampling unit, the contact signal of the gas density relay is isolated from its control circuit, and when the contact signal of the gas density relay is activated, and / or when a command to detect the contact insulation resistance is received, the insulation resistance detection unit can detect the contact insulation resistance value of the gas density relay.

[0084] The third aspect of this application provides a method for calibrating a gas density relay, including:

[0085] During normal operation, the gas density relay or gas density monitoring device monitors the gas density value inside the electrical equipment. Simultaneously, the gas density relay or gas density monitoring device monitors the gas density value inside the electrical equipment online via a first pressure sensor, a temperature sensor, and an intelligent control unit, and monitors the gas density value P in the second sealed gas chamber online via a second pressure sensor, a temperature sensor, and the intelligent control unit. 20BCS ;

[0086] The gas density relay or gas density monitoring device, based on the set calibration time and / or calibration command, and the gas density value, verifies the gas density relay under the following conditions:

[0087] The intelligent control unit adjusts the online verification contact signal sampling unit to the verification state. In the verification state, the online verification contact signal sampling unit cuts off the control circuit of the contact signal of the gas density relay body and connects the contact of the gas density relay body to the intelligent control unit.

[0088] The intelligent control unit regulates the pressure rise and fall of the second sealed gas chamber by controlling the pressure regulating mechanism, causing the gas density relay body to actuate its contacts. This contact actuation is transmitted to the intelligent control unit via an online verification contact signal sampling unit, enabling the intelligent control unit to detect the actuation of the gas density relay body; or...

[0089] The intelligent control unit regulates the pressure rise and fall of the second sealed air chamber by controlling the pressure regulating mechanism, which causes the gas density relay body to make contact action. The contact action is transmitted to the intelligent control unit through the online verification contact signal sampling unit. The intelligent control unit can detect the contact action of the gas density relay body and the gas density value of the second sealed air chamber, thus completing the direct or indirect verification of the contact signal action value of the gas density relay body.

[0090] After all contact signal verification work is completed, the intelligent control unit restores the pressure regulating mechanism and adjusts the online verification contact signal sampling unit to the working state, and the control circuit of the contact signal of the gas density relay body resumes normal operation.

[0091] Preferably, a method for calibrating a gas density relay includes:

[0092] The air path of the pressure regulating mechanism is connected to the second sealed air chamber of the gas density relay body, thereby connecting the air path of the pressure regulating mechanism to the second sealed air chamber and the second pressure sensor disposed in the second sealed air chamber.

[0093] During normal operation, the gas density relay or gas density monitoring device monitors the gas density value inside the electrical equipment. At the same time, the gas density relay or gas density monitoring device monitors the gas density value inside the electrical equipment online through the first pressure sensor, temperature sensor and intelligent control unit.

[0094] The gas density relay or gas density monitoring device, based on the set calibration time and / or calibration command, and the gas density value, verifies the gas density relay under the following conditions:

[0095] The intelligent control unit adjusts the online verification contact signal sampling unit to the verification state. In the verification state, the online verification contact signal sampling unit cuts off the control circuit of the contact signal of the gas density relay body and connects the contact of the gas density relay body to the intelligent control unit.

[0096] The intelligent control unit regulates the pressure rise and fall of the second sealed gas chamber by controlling the pressure regulating mechanism, causing the gas density relay body to activate a contact signal. The intelligent control unit acquires the pressure value P1 collected by the first pressure sensor and the temperature value T collected by the temperature sensor, as well as the pressure value P2 collected by the second pressure sensor, when the gas density relay body activates or switches. Based on the pressure values ​​P1, P2, and the gas pressure value P detected in the second sealed gas chamber at the beginning of this verification, the unit further analyzes these values. BCCSThe equivalent gas pressure value P is calculated; based on this equivalent gas pressure value P, and according to the gas pressure-temperature characteristics, it is converted into the pressure value corresponding to 20℃, i.e., the gas density value P. 20 Complete the online verification of the gas density relay; or,

[0097] The intelligent control unit acquires the gas density value P1 collected by the first pressure sensor and temperature sensor when the gas density relay body activates or switches its contact signal. 20 and the gas density value P2 collected by the second pressure sensor and temperature sensor. 20 And based on the gas density value P1 20 Gas density value P2 20 And the density value P detected in the second sealed gas chamber at the beginning of this verification. 20BCCS The gas density value P was calculated. 20 Complete the online verification of the gas density relay;

[0098] After all contact signal verification work is completed, the intelligent control unit restores the pressure regulating mechanism and adjusts the online verification contact signal sampling unit to the working state, and the control circuit of the contact signal of the gas density relay body resumes normal operation.

[0099] More preferably, when the gas density relay body generates a contact signal action or switches, its equivalent gas pressure value P = P1 - P2 + P BCCS Based on the equivalent gas pressure value P, and converted to the corresponding pressure value at 20℃ according to the gas pressure-temperature characteristics, i.e., the gas density value P, 20 Complete the online verification of the gas density relay; or,

[0100] When the gas density relay body experiences a contact signal activation or switching, its equivalent gas density value P 20 =P1 20 -P2 20 +P 20BCCS According to the equivalent gas density value P 20 The online calibration of the gas density relay is then completed.

[0101] More preferably, when the gas density relay body generates a contact signal action or switches, its gas density value P 20 and gas density value P1 20 P2 20 P 20BCCS The correspondence between them was designed into a data table, and based on the gas density value P1 20 Gas density value P2 20 and P 20BCCSThe corresponding gas density value P is obtained by querying the data table. 20 Complete the online verification of the gas density relay; or,

[0102] When the gas density relay body experiences a contact signal activation or switching, its gas density value P 20 and gas pressure values ​​P1, P2, P BCCS The data table is designed to show the correspondence between temperature values ​​T and gas pressure values ​​P1, P2, and P3. BCCS And by querying the data table for the temperature value T, the corresponding gas density value P can be obtained. 20 The online calibration of the gas density relay is then completed.

[0103] Preferably, the first pressure sensor and the second pressure sensor are absolute pressure sensors; or, the first pressure sensor and the second pressure sensor are relative pressure sensors; or, when the first pressure sensor and the second pressure sensor are not the same type of sensor, atmospheric pressure correction is performed.

[0104] Preferably, the contact signal includes an alarm and / or a lockout.

[0105] Preferably, the first pressure sensor and the temperature sensor are an integrated structure; or, the first pressure sensor and the temperature sensor are an integrated gas density transmitter; or, the first pressure sensor and the temperature sensor constitute a density detection sensor based on quartz tuning fork technology.

[0106] Preferably, after the gas density relay completes the calibration, if there is an abnormality, it can automatically issue an alarm and upload it to a remote location or send it to a designated receiver.

[0107] Preferably, the verification method further includes: displaying the gas density value and verification result on-site, or displaying the gas density value and verification result through the background.

[0108] Preferably, the verification method further includes: the intelligent control unit is controlled by on-site control and / or by background control.

[0109] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0110] The pressure regulating mechanism in this application is not connected to the SF6 main gas circuit of the gas density relay body or electrical equipment, but rather to the second sealed gas chamber of the gas density relay body, which is filled with standard compensation gas. Through the action of the pressure regulating mechanism, the gas density relay body causes contact actuation. This contact actuation is transmitted to the intelligent control unit via an online verification contact signal sampling unit. The intelligent control unit can detect the contact actuation of the gas density relay body and complete the verification of the contact signal actuation value of the gas density relay body. No on-site verification by maintenance personnel is required, achieving intelligent management of the gas density relay throughout its entire life cycle: repair only when there is a problem, and no maintenance service is needed when there is no problem. This application improves the reliability of the power grid, significantly reduces its sealing requirements, improves efficiency, reduces costs, and enhances the convenience and flexibility of on-site installation. It enables maintenance-free operation of the gas density relay, and the entire verification process achieves zero SF6 gas emissions, complying with environmental protection regulations. Attached Figure Description

[0111] The accompanying drawings, which constitute a part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0112] Figure 1 This is a schematic diagram of the structure of a gas density relay with online self-calibration function according to a preferred embodiment of the present invention;

[0113] Figure 2 This is a schematic diagram of the structure of a gas density relay with online self-calibration function according to a preferred embodiment of the present invention. Detailed Implementation

[0114] To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0115] Example 1:

[0116] like Figure 1 As shown, this embodiment provides a gas density relay or gas density monitoring device with online self-calibration function, including: a gas density relay body 1, a first pressure sensor 2, a second pressure sensor 4, a temperature sensor 3, a pressure regulating mechanism 5, an online calibration contact signal sampling unit 6, an intelligent control unit 7, a multi-port connector 9, and a valve 12; the gas density relay body 1, pressure sensor 2, temperature sensor 3, online calibration contact signal sampling unit 6, and intelligent control unit 7 are disposed on the multi-port connector 9.

[0117] The gas density relay body 1 mainly includes: a housing, a first bellows 104, a second bellows 103, a signal generator (a micro switch in this embodiment) 102, and a signal adjustment mechanism 101. The first open end of the first bellows 104 is fixed to the inner wall of the housing, and the first open end has an interface for communication with the insulating gas of the electrical equipment 8 (in this embodiment, the first open end is connected to a multi-way connector 9 through the interface, allowing the first bellows 104 to communicate with the insulating gas in the electrical equipment 8). The second open end of the first bellows 104 is sealed to a first sealing element 108. The inner wall of the first bellows 104, the first sealing element 108, the inner wall of the housing, and the electrical equipment 8 together form a first sealed gas chamber G1. The first open end of the second bellows 103 is sealed to the first seal 108, and the second open port of the second bellows 103 is connected to the inner wall of the housing through the second seal 109. The outer wall of the first bellows 104, the first seal 108, the outer wall of the second bellows 103, the second seal 109, and the inner wall of the housing together form a second sealed air chamber G2, which is filled with a gas with a density of P. 20BC The standard compensation gas is used. The signal adjustment mechanism 101 is connected to the first sealing element 108, and the signal generator 102 is set corresponding to the signal adjustment mechanism 101. The gas density relay body 1 outputs a contact signal through the signal generator 102. In this embodiment, the signal adjustment mechanism 101 includes a moving rod. One end of the moving rod extends into the second bellows 103 and is connected to the first sealing element 108, and moves with the deformation of the first bellows 104. The other end of the moving rod extends out of the second bellows 103 and is fixedly connected to a crossbar (or plate). The crossbar (or plate) is provided with several adjusting screws 10101. When the gas pressure in the second sealed gas chamber G2 changes, the first bellows 104 deforms with the pressure change, producing a certain displacement, which drives the moving rod 101 to move. The moving rod 101 drives the adjusting screws 10101 to touch the button of the signal generator 102, and the signal generator 102 issues an alarm and lockout signal.

[0118] In this embodiment, the first pressure sensor 2 is connected to the first bellows 104 of the gas density relay body 1; the second pressure sensor 4 is disposed inside the second sealed gas chamber G2 of the gas density relay body 1 and is connected to the second sealed gas chamber G2; the pressure regulating mechanism 5 is disposed outside the gas density relay body 1, and the gas path of the pressure regulating mechanism 5 is connected to the second sealed gas chamber G2, and is configured to regulate the gas pressure of the second sealed gas chamber G2 to cause the gas density relay body 1 to generate a contact signal action. The online verification contact signal sampling unit 6 is connected to the signal generator 102 of the gas density relay body 1 and is configured to sample the contact signal of the gas density relay body 1 when the contact signal action is generated, the contact signal including alarm and / or lockout. The intelligent control unit 7 is connected to the pressure regulating mechanism 5, the first pressure sensor 2, the second pressure sensor 4, the temperature sensor 3, and the online verification contact signal sampling unit 6, respectively. It is configured to control the pressure regulating mechanism 5, collect pressure and temperature values, and / or gas density values, and detect the contact signal action value and / or contact signal return value of the gas density relay body 1.

[0119] The gas density is monitored by the first bellows 104 and the second sealed gas chamber G2, and the gas density is monitored by the signal generator 102. When the gas density is lower than or / and higher than the set gas density, the signal generator 102 outputs an alarm or / and a lockout contact signal.

[0120] In this embodiment, the pressure regulating mechanism 5 is a cavity 51 with one open end. A piston 52 is located inside the cavity 51, and the piston 52 is equipped with a sealing ring 53. One end of the piston 52 is connected to an adjusting rod 54, the outer end of which is connected to a driving component 55. The other end of the piston 52 extends into the opening and contacts the inner wall of the cavity 51. The driving component 55 drives the adjusting rod 54, thereby moving the piston 52 within the cavity 51. The driving component 55 includes, but is not limited to, a magnetic force, a motor, a reciprocating motion mechanism, a Carnot cycle mechanism, a magnetically coupled thrust mechanism, a heating-generated thrust mechanism, an electrically heated thrust mechanism, a chemically reacted thrust mechanism, or a pneumatic component. In a preferred embodiment, the pressure regulating mechanism 5 further includes a sealing connector 58, which is disposed between the cavity 51 and the driving component 55, allowing the adjusting rod 54 to pass through the sealing connector 58 and connect to the driving component 55, ensuring excellent sealing performance of the entire pressure regulating mechanism 5. The sealing connector 58 includes, but is not limited to, a bellows, an airbag, and a sealing ring.

[0121] A valve 12 is provided between the pressure regulating mechanism 5 and the gas density relay body 1. One end of the valve 12 is connected to the second sealed gas chamber G2, and the other end is connected to the cavity 51 of the pressure regulating mechanism 5. The valve 12 is an electric valve, and / or a solenoid valve, or a piezoelectric valve, or a temperature-controlled valve, or a novel valve made of smart memory material that is opened or closed by electric heating. In the non-calibration state, the valve 12 is in the closed state; during calibration, the valve 12 is in the open state.

[0122] Of course, the positions of the first and second sealing chambers in this embodiment can be interchanged. For example, the inner wall of the first bellows 104, the first seal 108, and the inner wall of the outer shell together form the second sealing chamber, which is filled with a gas containing a density of P. 20BC The standard compensating gas; the outer wall of the first bellows 104, the first seal 108, the outer wall of the second bellows 103, the second seal 109, and the inner wall of the outer shell together form the first sealing gas chamber, which is provided with an interface for communication with the insulating gas of the electrical equipment. Specifically, the positions of the first and second sealing gas chambers can be flexibly designed as needed.

[0123] Working principle:

[0124] The intelligent control unit 7 obtains the corresponding 20℃ pressure value P based on the gas pressure and temperature monitored by the first pressure sensor 2 and temperature sensor 3 of the electrical equipment 8. 20 (i.e., gas density value), which can be remotely transmitted for online monitoring. Specifically, the intelligent control unit 7 acquires the gas density values ​​collected by the first pressure sensor 2 and temperature sensor 3; or, the intelligent control unit 7 acquires the pressure and temperature values ​​collected by the first pressure sensor 2 and temperature sensor 3, completing the online monitoring of the gas density of the monitored electrical equipment 8 by the gas density relay. Simultaneously, the intelligent control unit 7 acquires the gas density values ​​collected by the second pressure sensor 4 and temperature sensor 3; or, the intelligent control unit 7 acquires the pressure and temperature values ​​collected by the second pressure sensor 4 and temperature sensor 3, completing the monitoring of the gas density value P of the second sealed gas chamber G2. 20BCS Online monitoring. At this time, the gas density value of the first sealed gas chamber G1 is greater than the gas density value of the second sealed gas chamber G2, that is, the difference between the gas density values ​​of the first sealed gas chamber G1 and the second sealed gas chamber G2 is greater than a certain set value, by... Figure 1 It can be seen that there is a corresponding distance between the adjusting screw 10101 of the signal adjustment mechanism 101 and the signal generator 102. At this time, the adjusting screw 10101 does not contact the signal generator 102, that is, the signal generator 102 is not triggered, the signal generator 102 does not operate, and its contact signal is not output.

[0125] When it is necessary to verify the density relay body 1, if the gas density value P 20 ≥ Set security verification density value P S The gas density relay then issues a command, and the intelligent control unit 7 disconnects the control circuit of the gas density relay body 1. This ensures that the online verification of the gas density relay body 1 will not affect the safe operation of the electrical equipment 8, nor will it trigger false alarm signals or lock the control circuit during verification. This is because the gas density relay has already measured the gas density value P before verification begins. 20 ≥ Set security verification density value P S Based on monitoring and judgment, the gas in electrical equipment 8 is within the safe operating range, and gas leakage is a slow process, making the verification safe. Simultaneously, the intelligent control unit 7 connects to the contact sampling circuit of the gas density relay body 1. At the beginning of this verification, the intelligent control unit 7 detected the gas pressure value P in the second sealed gas chamber G2. BCCS The corresponding gas density value is P. 20BCCS .

[0126] Next, the valve 12 is opened by the intelligent control unit 7, so that the second sealed gas chamber G2 of the gas density relay body 1 is connected to the gas path of the pressure regulating mechanism 5 in the gas path. Then, the intelligent control unit 7 controls the drive component 55 of the pressure regulating mechanism 5 (which can be mainly implemented by a motor and gears, and the methods are diverse and flexible), thereby adjusting the piston 52 of the pressure regulating mechanism 5, so that the sealed cavity composed of the piston 52 and the second sealed gas chamber G2 of the gas density relay body 1 undergoes a volume change (volume decreases), the pressure of the gas in the second sealed gas chamber G2 of the gas density relay body 1 gradually increases, the pressure acting on the upper end face of the first bellows 104 increases, so that the upper end face of the first bellows 104 and the moving rod that drives the adjusting screw 10101 are displaced downward, the distance between the adjusting screw 10101 and the signal generator 102 will decrease, when the distance is less than the corresponding value, the adjusting screw 10101 of the signal regulating mechanism 101 contacts the signal generator 102, that is, triggers the signal generator 102, the contacts of the signal generator 102 are activated (connected), and a corresponding contact signal (alarm or lockout) is issued. The contact action is uploaded to the intelligent control unit 7 via the online verification contact signal sampling unit 6. The intelligent control unit 7 acquires the pressure value P1 collected by the first pressure sensor 2 and the temperature value T collected by the temperature sensor 3 when the gas density relay body 1 performs a contact signal action or switches, as well as the pressure value P2 collected by the second pressure sensor 4 and the gas pressure value P detected by the second sealed gas chamber G2 at the beginning of this verification. BCCS And based on pressure values ​​P1 and P2, P BCCSThe pressure value P is calculated; based on this pressure value P, and according to the gas pressure-temperature characteristics, it is converted to the pressure value corresponding to 20℃, i.e., the gas density value P. 20 The online verification of the gas density relay is completed. Or, more specifically, the intelligent control unit 7 acquires the gas density value P1 collected by the first pressure sensor 2 and temperature sensor 3 when the gas density relay body 1 activates a contact signal or switches. 20 The gas density value P2 collected by the second pressure sensor 4 and temperature sensor 3. 20 , and P 20BCCS And based on the gas density value P1 20 Gas density value P2 20 and P 20BCCS The gas density value P was calculated. 20 This completes the online verification of the gas density relay. Furthermore, when the gas density relay body 1 experiences a contact signal action or switching, its equivalent gas pressure value P = P1 - P2 + P BCCS Based on the equivalent gas pressure value P, and converted to the corresponding pressure value at 20℃ according to the gas pressure-temperature characteristics, i.e., the gas density value P, 20 This completes the online verification of the gas density relay. Alternatively, when the gas density relay body 1 experiences a contact signal action or switching, its gas density value P... 20 and gas density value P1 20 P2 20 P 20BCCS The correspondence between them was designed into a data table, and based on the gas density value P1 20 Gas density value P2 20 and P 20BCCS The corresponding gas density value P is obtained by querying the data table. 20 The gas density relay is calibrated online; or, when the gas density relay body 1 activates or switches its contact signal, its gas density value P is calibrated. 20 and gas pressure values ​​P1, P2, P BCCS The data table is designed to show the correspondence between temperature values ​​T and gas pressure values ​​P1, P2, and P3. BCCS And by querying the data table for the temperature value T, the corresponding gas density value P can be obtained. 20 The online calibration of the gas density relay is completed. For example, taking the parameters of the SF6 gas density relay being calibrated as follows: rated pressure 0.7 MPa, alarm pressure 0.65 MPa, and latching pressure 0.60 MPa (abs.). Assuming the calibration temperature T = 10℃, at the beginning of this calibration, the intelligent control unit 7 detects the gas pressure P in the second sealed gas chamber G2. BCCS=0.6186 MPa (abs.), corresponding to a gas density of P 20BCCS = 0.645MPa (abs.). Assuming that during the verification of the alarm contact signal activation, the pressure value P1 = 0.6756MPa and the temperature value T = 10℃ collected by the first pressure sensor 2 and temperature sensor 3, and the pressure value P2 = 0.6742MPa collected by the second pressure sensor 4, the equivalent gas pressure value P = P1 - P2 + P BCCS =0.6756-0.6742+0.6186=0.62MPa(abs.); Based on this equivalent gas pressure value P=0.62MPa(abs.), and according to the gas pressure-temperature characteristics, the corresponding pressure value at 20℃ is converted to the alarm contact's action value P. BJD20 The pressure is 0.6465 MPa (abs.), and the error is 0.6465 - 0.65 = -0.0035 MPa, which facilitates the online verification of the gas density relay alarm contact. Assuming that during the verification of the interlocking contact signal action, the pressure value P1 = 0.6756 MPa and the temperature value T = 10℃ collected by the first pressure sensor 2 and temperature sensor 3, and the pressure value P2 = 0.7253 MPa collected by the second pressure sensor 4, the equivalent gas pressure value P = P1 - P2 + P BCCS =0.6756-0.7253+0.6186=0.5689MPa(abs.); Based on this equivalent gas pressure value P=0.5689MPa(abs.), and converted to the corresponding pressure value at 20℃ according to the gas pressure-temperature characteristics, this is the action value P of the alarm interlock contact. BSD20 The pressure is 0.5928 MPa (abs.), and the error is 0.5928 - 0.60 = -0.0072 MPa. This facilitates the online verification of the gas density relay's locking contact. Repeat this verification process multiple times (e.g., 2-3 times), and then calculate the average value. This completes the verification of the gas density relay body 1.

[0127] Then, the intelligent control unit 7 disconnects the contact sampling circuit of the gas density relay body 1, at which point the contacts of the gas density relay body 1 are no longer connected to the intelligent control unit 7. Simultaneously, the intelligent control unit 7 controls the drive component 55 of the pressure regulating mechanism 5, thereby adjusting the piston 52 of the pressure regulating mechanism 5. This causes a volume change (volume increase) in the sealed cavity formed by the piston 52 and the second sealed gas chamber G2 of the gas density relay body 1, gradually reducing the pressure of the gas in the second sealed gas chamber G2 of the gas density relay body 1, and decreasing the pressure acting on the upper end face of the first bellows 104. After adjusting the gas density value of the second sealed chamber G2 to the specified set value, the gas pressure in the first sealed chamber G1 becomes greater than the gas pressure in the second sealed chamber G2. This pushes the upper end face of the first bellows 104 and the moving rod of the adjusting screw 10101 upwards, creating a corresponding distance between the first adjusting screw 10101 and the signal generator 102. The adjusting screw 10101 does not contact the signal generator 102. Simultaneously, the intelligent control unit 7 immediately closes the valve 12, preventing the second sealed chamber G2 of the gas density relay body 1 from being connected to the pressure regulating mechanism 5 in the gas path. The control circuit of the gas density relay body 1 is connected through the intelligent control unit 7, ensuring the normal operation of the density monitoring circuit of the gas density relay body 1. The gas density relay body 1 safely monitors the gas density of the electrical equipment 8, ensuring the safe and reliable operation of the electrical equipment 8. This facilitates the online calibration of the gas density relay body 1 without affecting the safe operation of the electrical equipment 8. In other words, after the gas density relay body 1 is calibrated online, it is restored to its original state so that the gas density relay body 1 can continue to monitor the gas density of the electrical equipment.

[0128] Once the gas density relay body 1 has completed its calibration, it will determine the result and display it. The method is flexible, specifically: 1) The gas density relay can display the result locally, for example, via indicator lights, digital displays, or LCD screens; 2) The gas density relay can upload the result via online remote communication, for example, to the backend of an online monitoring system; 3) It can upload wirelessly to a specific terminal, such as a mobile phone; 4) It can upload via other means; 5) It can upload abnormal results via alarm signal lines or dedicated signal lines; 6) It can upload independently or bundled with other signals. In short, after the gas density relay completes its online calibration, if there is an abnormality, it can automatically issue an alarm, which can be uploaded to a remote location or sent to a designated receiver, such as a mobile phone. Alternatively, after the gas density relay completes its calibration, if there is an abnormality, the intelligent control unit 7 can upload the result to a remote location (monitoring room, backend monitoring platform, etc.) via the alarm contact signal of the gas density relay body 1, and can also display the result locally. A simplified version of the gas density relay online calibration can upload the result of an abnormality via an alarm signal line. It can upload data according to a certain pattern. For example, in case of an anomaly, a contact can be connected in parallel with the alarm signal contact, and the connection can be opened and closed in a regular pattern, allowing the status to be determined through analysis. Alternatively, it can upload data through an independent verification signal line. Specifically, it can upload data when the status is good or when there is a problem. It can also upload data through remote online monitoring of density, upload verification results through a separate verification signal line, display the data locally, trigger an alarm locally, or upload data wirelessly via a smartphone network. The communication methods can be wired or wireless. Wired communication methods include industrial buses such as RS232, RS422, RS485, and CAN-BUS, fiber optic Ethernet, 4-20mA, HART, IIC, SPI, Wire, coaxial cable, and PLC power line carrier. Wireless communication methods include 2G / 3G / 4G / 5G, WIFI, Bluetooth, LoRa, LoRawan, Zigbee, infrared, ultrasonic, acoustic, satellite, optical, quantum communication, sonar, and sensors with built-in 5G / NB-IoT communication modules (such as NB-IoT). In summary, multiple methods and combinations can be used to fully guarantee the reliable performance of gas density relays.

[0129] The first pressure sensor 2 and the second pressure sensor 4 can be of the following types: absolute pressure sensor, relative pressure sensor, or a combination of absolute and relative pressure sensors, and there can be several of them. The pressure sensor type can be a diffused silicon pressure sensor, a MEMS pressure sensor, a chip-type pressure sensor, a coil-inductive pressure sensor (such as a pressure measurement sensor with a Baden tube and an induction coil), or a resistive pressure sensor (such as a pressure measurement sensor with a Baden tube and a slide wire resistor); it can be an analog pressure sensor or a digital pressure sensor. Pressure acquisition uses various pressure-sensing elements such as pressure sensors and pressure transmitters, for example, diffused silicon type, sapphire type, piezoelectric type, and strain gauge type (resistive strain gauge type, ceramic strain gauge type).

[0130] Temperature sensor 3 can be: thermocouple, thermistor, semiconductor type; it can be contact or non-contact; it can be a resistance temperature detector (RTD) or a thermocouple. In short, temperature acquisition can utilize various temperature-sensing elements such as temperature sensors and temperature transmitters.

[0131] The valve 12 can be controlled using various transmission methods, such as manual, electric, hydraulic, pneumatic, turbine, electromagnetic, electromagnetic-hydraulic, electro-hydraulic, pneumatic-hydraulic, spur gear, and bevel gear drives. It can operate according to predetermined requirements under the influence of pressure, temperature, or other sensor signals, or simply open or close without relying on sensor signals. The valve relies on a drive or automatic mechanism to make the opening and closing parts move up and down, slide, swing, or rotate, thereby changing the size of its flow channel area to achieve its control function. The valve 12 can be classified as an automatic valve, a power-driven valve, or a manual valve according to its drive method. Automatic valves can include: electromagnetic drive, electromagnetic-hydraulic drive, electro-hydraulic drive, turbine drive, spur gear drive, bevel gear drive, pneumatic drive, hydraulic drive, gas-hydraulic drive, electric drive, and motor drive. The valve can be automatic, manual, or semi-automatic. The calibration process can be completed automatically or semi-automatically with manual assistance. The valve is directly or indirectly connected to electrical equipment via a self-sealing valve, a manual valve, or a valve that does not need to be disassembled, either as an integrated unit or separately. Valves can be normally open or normally closed, and can be one-way or two-way, depending on the requirements. In short, the air path is opened or closed via an electrically controlled valve. The electrically controlled valve can be a solenoid valve, an electrically controlled ball valve, an electric valve, an electrically controlled proportional valve, etc.

[0132] The online verification contact signal sampling unit 6 mainly samples the contact signals of the gas density relay body 1. The basic requirements or functions of the online verification contact signal sampling unit 6 are: 1) It should not affect the safe operation of the electrical equipment during verification. That is, when the contact signals of the gas density relay body 1 activate during verification, it should not affect the safe operation of the electrical equipment; 2) The contact signal control circuit of the gas density relay body 1 should not affect the performance of the gas density relay, especially the performance of the intelligent control unit 7, and should not cause damage to the gas density relay or affect the testing work.

[0133] The basic requirement or function of the intelligent control unit 7 is to control the valve 12, the pressure regulating mechanism 5, and acquire signals. Specifically, it should be able to detect the pressure and temperature values ​​when the gas density relay body 1's contact signal is activated, and convert them into the corresponding pressure value P at 20°C. 20 (Density value), that is, the contact action value P of the gas density relay body 1 that can be detected. D20 This completes the calibration of the gas density relay body 1. Alternatively, it allows for the direct detection of the density value P when the contact signal of the gas density relay body 1 is activated. D20 Complete the calibration of the gas density relay body 1.

[0134] Of course, the intelligent control unit 7 can also: complete test data storage; and / or export test data; and / or print test data; and / or communicate with a host computer; and / or input analog and digital information. The intelligent control unit 7 also includes a communication module, which enables long-distance transmission of test data and / or verification results. When the rated pressure value of the gas density relay body 1 outputs a signal, the intelligent control unit 7 simultaneously acquires the current density value to complete the verification of the rated pressure value of the gas density relay body 1. Simultaneously, by testing the rated pressure value of the gas density relay body 1, the self-verification between the gas density relay body 1, pressure sensor 2, and temperature sensor 3 can be completed, achieving maintenance-free operation.

[0135] Electrical equipment 8 includes SF6 gas electrical equipment, SF6 mixed gas electrical equipment, environmentally friendly gas electrical equipment, or other insulating gas electrical equipment. Specifically, electrical equipment includes GIS, GIL, PASS, circuit breakers, current transformers, voltage transformers, transformers, gas-insulated switchgear, ring main units, etc.

[0136] The gas density relay body 1, the first pressure sensor 2, the temperature sensor 3, the valve 12, the pressure regulating mechanism 5, the online verification contact signal sampling unit 6, the intelligent control unit 7, and the multi-port connector 9 can be flexibly configured as needed. For example, the gas density relay body 1, the first pressure sensor 2, and the temperature sensor 3 can be placed together; or the valve 12 and the pressure regulating mechanism 5 can be placed together. In short, their configuration can be flexibly arranged and combined.

[0137] The gas density relay has a safety protection function. Specifically, when the gas density falls below a set value, the relay automatically stops online verification and issues a warning signal. For example, when the gas density value of the equipment is less than the set value P... S If the gas density value of the equipment is greater than or equal to (alarm pressure value + 0.02 MPa), then no verification will be performed. For example, online verification can only be performed when the gas density value of the equipment is greater than or equal to (alarm pressure value + 0.02 MPa).

[0138] Gas density relays can be calibrated online based on a set time or a set temperature (e.g., extreme high temperature, high temperature, extreme low temperature, low temperature, ambient temperature, 20 degrees Celsius, etc.). The error judgment requirements differ for online calibration at high temperature, low temperature, ambient temperature, and 20 degrees Celsius. For example, at 20 degrees Celsius, the accuracy requirement of the gas density relay can be 1.0 or 1.6, while at high temperatures it can be 2.5. Specific requirements can be implemented according to relevant standards based on temperature requirements. For instance, according to Article 4.8 of DL / T 259 "Calibration Procedure for Sulfur Hexafluoride Gas Density Relays," the accuracy requirements for each temperature value are specified.

[0139] Gas density relays can compare their error performance at different temperatures and over different time periods. That is, they can compare performance within the same temperature range at different times to determine the performance of gas density relays and electrical equipment. They offer comparisons of historical periods and comparisons between historical and current data.

[0140] The gas density relay can be calibrated repeatedly (e.g., 2-3 times), and the average value is calculated based on the results of each calibration. If necessary, the gas density relay can be calibrated online at any time.

[0141] The gas density relay features pressure and temperature measurement and software conversion functions. Without compromising the safe operation of electrical equipment, it can online detect the alarm and / or interlock contact action values ​​and / or return values ​​of the gas density relay body 1. Of course, the return values ​​of the alarm and / or interlock contact signals can be omitted upon request. Simultaneously, the gas density relay can also monitor the gas density, and / or pressure, and / or temperature values ​​of electrical equipment online and upload them to the target equipment for online monitoring.

[0142] Example 2:

[0143] The difference between this embodiment and Embodiment 1 is that the pressure regulating mechanism 5 mainly consists of an air bladder 51, a piston 52, a sealing ring 53, a connecting rod 54, and a driving component 55. The air bladder 51 is connected to the second sealed air chamber G2 of the gas density relay body 1. Under the control of the intelligent control unit 7, the pressure regulating mechanism 5 causes the driving component 55 to push the connecting rod 54, which in turn pushes the piston 52, thereby causing a volume change in the air bladder 51, thus completing the rise and fall of the gas pressure in the second sealed air chamber G2.

[0144] In another preferred embodiment, the pressure regulating mechanism 5 can also be a solenoid valve, which is sealed inside a housing. Under the control of the intelligent processor 7, the pressure regulating mechanism 5 causes the solenoid valve to open, resulting in a pressure change, thereby raising or lowering the gas pressure in the second sealed chamber G2.

[0145] In another preferred embodiment, the pressure regulating mechanism 5 may also consist of a bellows and a driving component. The bellows is sealed together with the second sealed gas chamber G2 of the gas density relay body 1, forming a reliable sealed cavity. Under the control of the intelligent processor 7, the pressure regulating mechanism 5 causes the driving component to push the bellows to change volume, thereby causing a change in the volume of the sealed cavity, thus completing the rise and fall of the gas pressure in the second sealed gas chamber G2.

[0146] In another preferred embodiment, the pressure regulating mechanism 5 may also consist of a gas chamber, a heating element, and a heat insulation component. The gas chamber is sealed together with the second sealed gas chamber G2 of the gas density relay body 1. The gas chamber has a heating element on its outside (or inside). By heating, the temperature changes, thereby completing the rise and fall of the gas pressure in the second sealed gas chamber G2.

[0147] Of course, the pressure regulating mechanism 5 can also take many other forms, not limited to those listed above. Other mechanisms that can achieve pressure raising and lowering functions are also covered within the scope of protection of this application.

[0148] It should be noted that a gas density relay with online self-calibration function generally refers to a gas density relay whose components are designed as a single unit; while a gas density monitoring device generally refers to a gas density monitoring device whose components are designed as separate units, allowing for flexible assembly. Additionally, the internal gas chamber of the first bellows can be designed as a second sealed gas chamber, i.e., filled with a gas with a density value of P. 20BC The standard compensation gas is used; the cavity outside the first bellows is designed as the first sealed gas chamber, connecting to electrical equipment. The gas density relay can be upgraded from the existing gas density relay in the substation.

[0149] In summary, the pressure regulating mechanism 5 of this application is not connected to the SF6 main gas circuit of the gas density relay body 1 or the electrical equipment 8, but rather to the second sealed gas chamber G2 of the gas density relay body 1, which is filled with standard compensation gas. Through the action of the pressure regulating mechanism 5, the gas density relay body 1 experiences contact action. This contact action is transmitted to the intelligent control unit 7 via the online verification contact signal sampling unit 6. The intelligent control unit 7 can detect the contact action of the gas density relay body 1 and complete the verification of the contact signal action value of the gas density relay body. No on-site verification by maintenance personnel is required, achieving intelligent management of the gas density relay throughout its entire lifecycle: repairs are only performed when problems arise, and maintenance services are not needed when there are no problems. This application improves the reliability of the power grid, significantly reduces its sealing requirements, increases efficiency, reduces maintenance costs, and improves the convenience and flexibility of on-site installation. It enables maintenance-free operation of the gas density relay, and the entire verification process achieves zero SF6 gas emissions, complying with environmental regulations.

[0150] The specific embodiments of the present invention have been described in detail above, but they are merely examples, and the present invention is not limited to the specific embodiments described above. For those skilled in the art, any equivalent modifications and substitutions to the present invention are also within the scope of the present invention. Therefore, all equivalent changes and modifications made without departing from the spirit and scope of the present invention should be covered within the scope of the present invention.

Claims

1. A gas density relay with online self-calibration function, characterized in that, include: The gas density relay body, first pressure sensor, second pressure sensor, temperature sensor, pressure regulating mechanism, online verification contact signal sampling unit, and intelligent control unit; The gas density relay body includes: a housing, a first sealed gas chamber connected to the insulating gas chamber of an electrical device within the housing, and a second sealed gas chamber filled with a standard compensation gas; the second sealed gas chamber is filled with a gas having a density value of P. 20BC Standard compensating gas; The first pressure sensor is connected to the first sealed gas chamber of the gas density relay body; The second pressure sensor is connected to the second sealed gas chamber of the gas density relay body; The pressure regulating mechanism is disposed outside the gas density relay body. The gas passage of the pressure regulating mechanism is connected to the second sealed gas chamber and is configured to regulate the gas pressure of the second sealed gas chamber, so that the gas density relay body generates a contact signal action. The online verification contact signal sampling unit is connected to the signal generator of the gas density relay body and is configured to sample the contact signal when the gas density relay body generates a contact signal action. The intelligent control unit is connected to the pressure regulating mechanism, the first pressure sensor, the second pressure sensor, the temperature sensor, and the online verification contact signal sampling unit, and is configured to control the pressure regulating mechanism, acquire pressure and temperature values, and / or acquire gas density values, and detect the contact signal action value and / or contact signal return value of the gas density relay body. The contact signals include alarm and / or interlock; In the verification state, the online verification contact signal sampling unit cuts off the control circuit of the contact signal of the gas density relay body and connects the contact of the gas density relay body to the intelligent control unit. The intelligent control unit regulates the pressure rise and fall of the second sealed gas chamber by controlling the pressure regulating mechanism, causing the gas density relay body to activate a contact signal. The intelligent control unit acquires the pressure value P1 collected by the first pressure sensor and the temperature value T collected by the temperature sensor, as well as the pressure value P2 collected by the second pressure sensor, when the gas density relay body activates a contact signal or switches. Based on the pressure values ​​P1, P2, and the gas pressure value P detected in the second sealed gas chamber at the beginning of this verification, the unit then... BCCS The equivalent gas pressure value P is calculated; based on this equivalent gas pressure value P, and according to the gas pressure-temperature characteristics, it is converted into the pressure value corresponding to 20℃, i.e., the gas density value P. 20 Complete the online verification of the gas density relay; or, The intelligent control unit acquires the gas density value P1 collected by the first pressure sensor and temperature sensor when the gas density relay body activates or switches its contact signal. 20 and the gas density value P2 collected by the second pressure sensor and temperature sensor. 20 And based on the gas density value P1 20 Gas density value P2 20 And the density value P detected in the second sealed gas chamber at the beginning of this verification. 20BCCS The gas density value P was calculated. 20 Complete the online verification of the gas density relay; After all contact signal verification work is completed, the intelligent control unit restores the pressure regulating mechanism and adjusts the online verification contact signal sampling unit to the working state, and the control circuit of the contact signal of the gas density relay body resumes normal operation.

2. The gas density relay according to claim 1, characterized in that, The gas density relay body includes: a housing, a first bellows, a second bellows, a signal generator, and a signal conditioning mechanism; wherein, the first open end of the first bellows is fixed to the inner wall of the housing, and the second open end of the first bellows is sealed to a first sealing element; the inner wall of the first bellows, the first sealing element, and the inner wall of the housing together form a first sealed gas chamber, and the first sealed gas chamber has an interface for communicating with the insulating gas of electrical equipment; the first open end of the second bellows is sealed to the first sealing element, and the second open port of the second bellows is connected to the inner wall of the housing through a second sealing element; the outer wall of the first bellows, the first sealing element, the outer wall of the second bellows, the second sealing element, and the inner wall of the housing together form a second sealed gas chamber; the signal conditioning mechanism is connected to the first sealing element, and the signal generator is provided corresponding to the signal conditioning mechanism.

3. The gas density relay according to claim 2, characterized in that: The outer diameter of the first bellows is larger than the outer diameter of the second bellows.

4. The gas density relay according to claim 2, characterized in that: The signal adjustment mechanism includes a movable rod, one end of which extends into the second bellows and is connected to the first seal, and moves with the deformation of the first bellows; the other end of the movable rod extends out of the second bellows and is fixedly connected to a crossbar, which is provided with an adjusting screw, which is used to activate the signal generator under the pushing force of the movable rod.

5. The gas density relay according to claim 2, characterized in that: The signal generator includes a micro switch or a magnetically assisted electrical contact, and the gas density relay body outputs a contact signal through the signal generator.

6. The gas density relay according to claim 1, characterized in that: The intelligent control unit acquires the gas density values ​​collected by the first pressure sensor and temperature sensor; or, the intelligent control unit acquires the pressure and temperature values ​​collected by the first pressure sensor and temperature sensor to complete the online monitoring of the gas density of the monitored electrical equipment by the gas density relay.

7. The gas density relay according to claim 1, characterized in that: The intelligent control unit acquires the gas density value P collected by the second pressure sensor and temperature sensor. 20BCS Alternatively, the intelligent control unit acquires the pressure value P collected by the second pressure sensor. BCS Based on the temperature value T collected by the temperature sensor, the gas density value P of the second sealed gas chamber is determined. 20BCS Online monitoring; or, The intelligent control unit acquires the gas density value P collected by the second pressure sensor and temperature sensor. 20BCS Alternatively, the intelligent control unit acquires the pressure value collected by the second pressure sensor and the temperature value collected by the temperature sensor to obtain the gas density value P of the second sealed gas chamber. 20BCS This completes the indirect verification of the contact signal action value of the gas density relay body. or, The intelligent control unit acquires the gas density value P collected by the second pressure sensor and temperature sensor. 20BCS Alternatively, the intelligent control unit acquires the pressure value collected by the second pressure sensor and the temperature value collected by the temperature sensor to obtain the gas density value P of the second sealed gas chamber. 20BCS When |P 20BC -P 20BCS | When the set threshold is exceeded, an alarm signal is issued.

8. The gas density relay according to claim 1, characterized in that: It also includes a valve, one end of which is connected to the air passage of the pressure regulating mechanism, and the other end of which is connected to the second sealing air chamber.

9. The gas density relay according to claim 1, characterized in that: The pressure regulating mechanism is a sealed air chamber, with a heating element and / or a cooling element installed outside or inside the sealed air chamber. Heating by the heating element and / or cooling by the cooling element causes a temperature change in the gas inside the sealed air chamber, thereby adjusting the pressure in the second sealed air chamber; or... The pressure regulating mechanism is a cavity with one open end, the other end of which is connected to the second sealed air chamber. A piston is located within the cavity, one end of which is connected to an adjusting rod. The outer end of the adjusting rod is connected to a driving component. The other end of the piston extends into the opening and is in sealing contact with the inner wall of the cavity. The driving component drives the adjusting rod, thereby moving the piston within the cavity. Alternatively... The pressure regulating mechanism is a sealed air chamber. Inside the sealed air chamber is a piston that is in sealed contact with the inner wall of the sealed air chamber. Outside the sealed air chamber is a driving component that pushes the piston to move within the chamber via electromagnetic force; or... The pressure regulating mechanism is an airbag connected at one end to a driving component. The airbag changes volume under the drive of the driving component, and the airbag is connected to the second sealed air chamber; or... The pressure regulating mechanism is a bellows, one end of which is connected to the second sealing air chamber, and the other end of which extends and retracts under the drive of the driving component. or, The pressure regulating mechanism is a vent valve, which includes an electric valve; or... The pressure regulating mechanism is a compressor; or... The pressure regulating mechanism is a pump, which includes a booster pump or an electric air pump; or... The pressure regulating mechanism is a pressure boosting valve; The driving component includes one of the following: magnetic force, motor, reciprocating motion mechanism, Carnot cycle mechanism, heating to generate thrust mechanism, chemical reaction to generate thrust mechanism, and pneumatic component.

10. The gas density relay according to claim 1, characterized in that: The first pressure sensor and temperature sensor are integrated into one unit.

11. The gas density relay according to claim 10, characterized in that: The first pressure sensor and temperature sensor are an integrated gas density transmitter.

12. The gas density relay according to claim 1, characterized in that: The online verification contact signal sampling unit and the intelligent control unit are configured together.

13. The gas density relay according to claim 1, characterized in that: The first pressure sensor includes at least one pressure sensor; or, the first pressure sensor is a gas density transmitter composed of a pressure sensor and a temperature sensor; or, the first pressure sensor is a density detection sensor using quartz tuning fork technology.

14. The gas density relay according to claim 1, characterized in that: The first pressure sensor is installed in the gas path of the gas density relay body; the temperature sensor is installed in or outside the gas path of the gas density relay body, or inside or outside the gas density relay body.

15. The gas density relay according to claim 1, characterized in that: The online verification contact signal sampling unit includes an isolation sampling element, which is controlled by the gas density relay body, a pressure regulating mechanism, or an intelligent control unit. In the non-verification state, the online verification contact signal sampling unit is relatively isolated from the contact signal of the gas density relay body through the isolation sampling element. In the verification state, the online verification contact signal sampling unit cuts off the contact signal control circuit of the gas density relay body through the isolation sampling element, connecting the contacts of the gas density relay body to the intelligent control unit. The isolation sampling element includes one of the following: a limit switch, a micro switch, a button, an electric switch, an electromagnetic relay, an optocoupler, or a thyristor.

16. The gas density relay according to claim 1, characterized in that: It also includes a multi-port connector, on which the gas density relay body and the first pressure sensor are mounted; or, The pressure regulating mechanism is fixed to the multi-port connector; or... The gas density relay body, the first pressure sensor, and the pressure regulating mechanism are mounted on the multi-port connector; or... The online verification contact signal sampling unit, intelligent control unit, and temperature sensor are installed on the multi-port connector.

17. The gas density relay according to claim 1, characterized in that: The system comprises at least two gas density relay bodies, at least two first pressure sensors, at least two second pressure sensors, at least two pressure regulating mechanisms, at least two online verification contact signal sampling units, a smart control unit, and a temperature sensor to complete the online verification of the gas density relays. or, The system comprises at least two gas density relay bodies, at least two first pressure sensors, at least two second pressure sensors, at least two pressure regulating mechanisms, at least two temperature sensors, at least two online verification contact signal sampling units, and an intelligent control unit to complete the online verification of the gas density relays.

18. The gas density relay according to claim 1, characterized in that: The intelligent control unit is controlled through on-site control and / or through back-end control.

19. A gas density monitoring device with online self-calibration function, characterized in that, The gas density monitoring device includes a gas density relay with online self-calibration function as described in any one of claims 1-18.

20. A calibration method for a gas density relay with online self-calibration function as described in claim 1, characterized in that, include: The air path of the pressure regulating mechanism is connected to the second sealed air chamber of the gas density relay body, thereby connecting the air path of the pressure regulating mechanism to the second sealed air chamber and the second pressure sensor disposed in the second sealed air chamber. During normal operation, 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 first pressure sensor, temperature sensor and intelligent control unit. The gas density relay, based on the set calibration time and / or calibration command, and the gas density value, will calibrate the gas density relay under the following conditions: The intelligent control unit adjusts the online verification contact signal sampling unit to the verification state. In the verification state, the online verification contact signal sampling unit cuts off the control circuit of the contact signal of the gas density relay body and connects the contact of the gas density relay body to the intelligent control unit. The intelligent control unit regulates the pressure rise and fall of the second sealed gas chamber by controlling the pressure regulating mechanism, causing the gas density relay body to activate a contact signal. The intelligent control unit acquires the pressure value P1 collected by the first pressure sensor and the temperature value T collected by the temperature sensor, as well as the pressure value P2 collected by the second pressure sensor, when the gas density relay body activates or switches. Based on the pressure values ​​P1, P2, and the gas pressure value P detected in the second sealed gas chamber at the beginning of this verification, the unit further analyzes these values. BCCS The equivalent gas pressure value P is calculated; based on this equivalent gas pressure value P, and according to the gas pressure-temperature characteristics, it is converted into the pressure value corresponding to 20℃, i.e., the gas density value P. 20 Complete the online verification of the gas density relay; or, The intelligent control unit acquires the gas density value P1 collected by the first pressure sensor and temperature sensor when the gas density relay body activates or switches its contact signal. 20 and the gas density value P2 collected by the second pressure sensor and temperature sensor. 20 And based on the gas density value P1 20 Gas density value P2 20 And the density value P detected in the second sealed gas chamber at the beginning of this verification. 20BCCS The gas density value P was calculated. 20 Complete the online verification of the gas density relay; After all contact signal verification work is completed, the intelligent control unit restores the pressure regulating mechanism and adjusts the online verification contact signal sampling unit to the working state, and the control circuit of the contact signal of the gas density relay body resumes normal operation.

21. The calibration method for a gas density relay with online self-calibration function according to claim 20, characterized in that, include: When the gas density relay body activates or switches due to a contact signal, its equivalent gas pressure value P = P1 - P2 + P BCCS Based on the equivalent gas pressure value P, and converted to the corresponding pressure value at 20℃ according to the gas pressure-temperature characteristics, i.e., the gas density value P, 20 Complete the online verification of the gas density relay; or, When the gas density relay body experiences a contact signal activation or switching, its equivalent gas density value P 20 =P1 20 -P2 20 +P 20BCCS According to the equivalent gas density value P 20 The online calibration of the gas density relay is then completed.

22. The calibration method for a gas density relay with online self-calibration function according to claim 20, characterized in that, include: When the gas density relay body experiences a contact signal activation or switching, its gas density value P 20 and gas density value P1 20 P2 20 P 20BCCS The correspondence between them was designed into a data table, and based on the gas density value P1 20 Gas density value P2 20 and P 20BCCS The corresponding gas density value P is obtained by querying the data table. 20 Complete the online verification of the gas density relay; or, When the gas density relay body experiences a contact signal activation or switching, its gas density value P 20 and gas pressure values ​​P1, P2, P BCCS The data table is designed to show the correspondence between temperature values ​​T and gas pressure values ​​P1, P2, and P3. BCCS And by querying the data table for the temperature value T, the corresponding gas density value P can be obtained. 20 The online calibration of the gas density relay is then completed.

23. The calibration method for a gas density relay with online self-calibration function according to claim 20, characterized in that, This includes: the first pressure sensor and the second pressure sensor being absolute pressure sensors; or the first pressure sensor and the second pressure sensor being relative pressure sensors; or, when the first pressure sensor and the second pressure sensor are not the same type of sensor, atmospheric pressure correction is performed.

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