CN110429003B - Transmitter for on-line check density relay and implementation method and system thereof - Google Patents

Abstract

The present application provides a transmitter for online calibration of density relays and its implementation method, including a housing, and a pressure sensor, a temperature sensor, a communication module, an intelligent control unit and a device connection joint arranged in the housing, wherein the transmitter is connected to the electrical equipment via the device connection joint; the transmitter also includes a gas density relay, a valve, a pressure regulating mechanism and an online calibration contact signal sampling unit. The transmitter controls the pressure rise and fall of the pressure regulating mechanism through the intelligent control unit, so that the gas density relay generates contact action. The intelligent control unit detects the contact action value and/or return value of the gas density relay based on the density value when the contact is in action, and realizes remote transmission through the communication module to complete the calibration of the gas density relay, without the need for maintenance personnel to go to the site for operation, thus achieving maintenance-free electrical equipment. The present application also provides a monitoring system using the above-mentioned transmitter.

Description

Transmitter for online calibration of density relay and implementation method and system thereof

Technical Field

The present invention relates to the field of electric power technology, and in particular to a transmitter used for online calibration of a density relay on high-voltage and medium-voltage electrical equipment, and an implementation method and system thereof.

Background Art

Gas density relays are generally used to monitor and control the density of insulating gas in high-voltage and medium-voltage electrical equipment. A contact signal control circuit is provided inside the relay. The gas path of the gas density relay is connected to the gas chamber of the high-voltage and medium-voltage electrical equipment. When a gas leak is detected, the contacts of the gas density relay will operate to generate contact signals. The contact signal control circuit will issue an alarm or perform a lockout according to the contact signal, thereby achieving safe operation protection of the electrical equipment.

At present, SF6 (sulfur hexafluoride) electrical equipment has been widely used in power departments and industrial and mining enterprises, promoting the rapid development of the power industry. In recent years, with the rapid development of the economy, the capacity of China's power system has expanded dramatically, and the amount of SF6 electrical equipment has increased. The role of SF6 gas in high-voltage electrical equipment is arc extinguishing and insulation. If the density of SF6 gas in high-voltage electrical equipment decreases and the water content exceeds the standard, it will seriously affect the safe operation of SF6 high-voltage electrical equipment: 1) The density of SF6 gas decreases to a certain extent, which will lead to the loss of insulation and arc extinguishing performance. 2) With the participation of some metal objects, SF6 gas can react with water at a high temperature of more than 200°C to generate active HF and _SOF2 , corrode insulation and metal parts, and generate a lot of heat, causing the pressure of the gas chamber to increase. 3) When the temperature drops, excessive moisture may form condensation water, which will significantly reduce the insulation strength of the surface of the insulation parts, and even flashover, causing serious harm. Therefore, the power grid operation regulations stipulate that the density and water content of SF6 gas must be regularly tested before the equipment is put into operation and during operation.

As unmanned substations develop towards networking and digitalization, and the requirements for remote control and telemetry continue to increase, online monitoring of the gas density and micro-water content of SF6 electrical equipment has important practical significance. With the continuous and vigorous development of China's smart grid, smart high-voltage electrical equipment, as an important component and key node of smart substations, plays a vital role in the safety of smart grids. Most high-voltage electrical equipment is currently SF6 gas-insulated equipment. If the gas density decreases (such as caused by leakage, etc.), it will seriously affect the electrical performance of the equipment and cause serious hidden dangers to safe operation. At present, online monitoring of the gas density value in SF6 high-voltage electrical equipment has become very common. The existing gas density monitoring system (device) is basically: 1) Using remote SF6 gas density relays to realize the collection and upload of density, pressure and temperature, and realize online monitoring of gas density. 2) Using gas density transmitters to realize the collection and upload of density, pressure and temperature, and realize online monitoring of gas density. SF6 gas density relays are core and key components. However, due to the harsh operating environment of high-voltage substations, especially the strong electromagnetic interference, the remote transmission SF6 gas density relay in the currently used gas density monitoring system (device) is composed of a mechanical density relay and an electronic remote transmission part; in addition, the traditional mechanical density relay is still retained in the power grid system using gas density transmitters. The mechanical density relay has one, two or three sets of mechanical contacts. When the pressure reaches the alarm, lockout or overpressure state, the information is transmitted to the target device terminal through the contact connection circuit in time to ensure the safe operation of the equipment. At the same time, the monitoring system is also equipped with a safe and reliable circuit transmission function, which establishes an effective platform for realizing real-time data remote data reading and information monitoring, and can transmit information such as pressure, temperature, density, etc. to the target device (such as a computer terminal) in time to realize online monitoring.

Regular inspection of gas density relays on SF6 electrical equipment is a necessary measure to prevent accidents and ensure the safe and reliable operation of SF6 electrical equipment; the "Electricity Preventive Test Regulations" and the "Twenty-five Key Requirements for Preventing Major Accidents in Electricity Production" both require regular inspection of gas density relays. From the actual operation situation, regular inspection of gas density relays is one of the necessary means to ensure the safe and reliable operation of power equipment. Therefore, the inspection of SF6 gas density relays has been highly valued and popularized in the power system, and has been implemented by power supply companies, power plants, and large factories and mines. In order to complete the on-site inspection and testing of gas density relays, power supply companies, power plants, and large factories and mines need to be equipped with testers, equipment vehicles, and high-value SF6 gas. Including the power outage business losses during the inspection, a rough calculation shows that the annual inspection cost of each high-voltage switch station is about tens of thousands to hundreds of thousands of yuan. In addition, if the on-site inspection of the inspectors is not standardized, there are safety hazards. Therefore, it is very necessary to innovate the existing gas density relays so that the gas density relays or monitoring systems that realize online gas density monitoring also have the calibration function of the gas density relays, thereby completing the regular calibration of the (mechanical) gas density relays without the need for maintenance personnel to go to the site, greatly improving efficiency and reducing costs. At the same time, the online self-calibrating gas density relays or monitoring systems composed of them can accurately measure the micro-water value inside the gas chamber of electrical equipment.

Summary of the invention

The purpose of the present invention is to provide a transmitter for online calibration of density relays used on high-voltage and medium-voltage electrical equipment, and a method and system for implementing the same, which are used to monitor the gas density of gas-insulated or arc-extinguishing electrical equipment while also completing online calibration of the gas density relay, thereby improving efficiency, reducing operating and maintenance costs, and ensuring safe operation of the power grid.

To achieve the above object, the present invention adopts the following technical solutions:

A first aspect of the present application provides a transmitter for online calibration of a density relay.

A second aspect of the present application provides a monitoring system, which is composed of the transmitter for online calibration of the density relay described in the first aspect, or includes the transmitter for online calibration of the density relay described in the first aspect.

The transmitter for online calibration of a density relay described in the present application comprises: a housing, and a pressure sensor, a temperature sensor, a communication module, an intelligent control unit and a device connection joint arranged in the housing, wherein the transmitter is connected to an electrical device and a gas density relay through the device connection joint; the transmitter also comprises a valve, a pressure regulating mechanism and an online calibration contact signal sampling unit; wherein,

The valve has one end connected to the equipment connection joint, and the other end connected to the gas path of the gas density relay and the pressure sensor;

The pressure regulating mechanism, whose gas circuit is connected with the gas circuits of the gas density relay and the pressure sensor, is configured to regulate the pressure rise and fall of the gas circuit of the gas density relay so that the gas density relay generates a contact action;

The pressure sensor is connected to the gas density relay on the gas path;

The online verification contact signal sampling unit is connected to the signal generator of the gas density relay and the intelligent control unit respectively, and is used to sample the contact signal generated when the gas density relay has a contact action, and transmit the contact signal to the intelligent control unit;

The intelligent control unit is also connected to the valve, the pressure regulating mechanism, the pressure sensor, the temperature sensor and the communication module respectively, and is used to convert the data collected by the pressure sensor and the temperature sensor into a standard signal, control the closing or opening of the valve, complete the control of the pressure regulating mechanism, receive the pressure value and temperature value and/or gas density value when the contact of the gas density relay is actuated, and transmit the pressure value and temperature value and/or gas density value to the corresponding detection system or target device through the communication module;

Wherein, the contact signal includes alarm and/or lock.

Preferably, the signal generator comprises a micro switch or a magnetically assisted electric contact, and the gas density relay outputs a contact signal through the signal generator.

Preferably, the intelligent control unit converts the data collected by the pressure sensor and the temperature sensor into a gas density value (i.e., the pressure value corresponding to 20°C); or converts it into a digital signal of the gas density value (i.e., the pressure value corresponding to 20°C) to complete online monitoring of gas density.

More preferably, the intelligent control unit adopts a mean method (average value method) to calculate the gas density value, wherein the mean method is: within a set time interval, the acquisition frequency is set, and the average value of all N gas density values acquired at different time points is calculated to obtain the gas density value; or,

In a set time interval and a set temperature interval step, the density values corresponding to N different temperature values collected within the entire temperature range are averaged to obtain the gas density value; or, in a set time interval and a set pressure interval step, the density values corresponding to N different pressure values collected within the entire pressure change range are averaged to obtain the gas density value;

Wherein, N is a positive integer greater than or equal to 1.

Preferably, the intelligent control unit converts the data collected by the pressure sensor and the temperature sensor into a current signal corresponding to the density value.

More preferably, the current signal is a direct current signal.

Furthermore, the DC current signal is 0-10 mA or 4-20 mA.

Preferably, the intelligent control unit converts the data collected by the pressure sensor and the temperature sensor into a voltage signal corresponding to the density value.

More preferably, the voltage signal is a DC voltage signal.

Furthermore, the DC voltage signal is 1-5V.

Preferably, the intelligent control unit automatically controls the entire verification process, including all peripherals, logics, and inputs and outputs, based on the embedded system algorithm and control program of the microprocessor.

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

Preferably, the intelligent control unit obtains the pressure value and temperature value collected by the pressure sensor and temperature sensor when the contact of the gas density relay is actuated, and converts them into a pressure value corresponding to 20°C, i.e., a gas density value, according to the gas pressure-temperature characteristics, to complete the online verification of the gas density relay.

Preferably, the transmitter automatically implements the test of the absolute pressure type gas density relay and/or the relative pressure type gas density relay. That is, it can test the density relay of the absolute pressure structure-absolute pressure display type, the density relay of the absolute pressure structure-gauge pressure display type, the density relay of the gauge pressure structure-absolute pressure display type, and the density relay of the gauge pressure structure-gauge pressure display type. Specifically, the transmitter includes a relative pressure sensor and/or an absolute pressure sensor.

Preferably, the intelligent control unit is provided with an electrical interface, which is used to complete test data storage, and/or test data export, and/or test data printing, and/or data communication with a host computer, and/or input analog and digital information.

More preferably, the electrical interface is provided with an electrical interface protection circuit to prevent damage to the interface due to misconnection by the user and/or to prevent electromagnetic interference.

Preferably, the intelligent control unit is also provided with a clock, and the clock is used to regularly set the verification time, or record the test time, or record the event time.

Preferably, the transmitter monitors the gas density value of the electrical equipment online, and if there is any abnormality, the transmitter starts an online calibration of the gas density relay.

Preferably, after the transmitter completes the calibration of the gas density relay, the intelligent control unit automatically generates a calibration report for the gas density relay. If there is any abnormality, an alarm is automatically issued, and/or uploaded to a remote end, and/or sent to a designated receiver (for example, to a mobile phone).

Preferably, after the transmitter completes the calibration of the gas density relay, if there is any abnormality, the intelligent control unit uploads the alarm contact signal of the gas density relay to the remote end, and/or sends it to a designated receiver (for example, to a mobile phone) through a communication module.

Preferably, the intelligent control unit includes: a microprocessor, a human-machine interface, a valve controller, a pressure regulating mechanism position detection element, and an execution controller (component).

Preferably, the valve is an electric valve.

Preferably, the valve is a solenoid valve.

More preferably, the valve is a permanent magnet solenoid valve.

Preferably, the valve is a piezoelectric valve, or a temperature-controlled valve, or a new type of valve made of intelligent memory material and opened or closed by electric heating.

Preferably, the valve is closed or opened by bending or pinching a hose.

Preferably, the valve is sealed within a cavity or housing.

Preferably, the valve and the pressure regulating mechanism are sealed within a cavity or housing.

Preferably, when the valve is closed, the pressure regulating mechanism increases the pressure and the load increases, or when the pressure regulating mechanism decreases the pressure and the load decreases, the load change rate is no more than 10‰ of the range of the gas density relay per second.

Preferably, pressure sensors are provided on both sides of the gas path of the valve; or, pressure or density detectors are provided on both sides of the gas path of the valve.

Preferably, a density relay or a density switch is provided at the front end of the valve to output a signal of a safety check set point, and the signal is connected to the intelligent control unit.

Preferably, the gas density relay is arranged on or in the housing of the transmitter.

Preferably, the temperature sensor is disposed on or in a housing of a gas density relay; or is disposed on or in a housing of a transmitter.

Preferably, at least one temperature sensor is arranged near, on or integrated into a temperature compensation element of a gas density relay, and the temperature compensation element adopts a temperature compensation sheet or a gas enclosed in a housing. Preferably, at least one temperature sensor is arranged at one end of a pressure detector of a gas density relay close to the temperature compensation element, and the pressure detector comprises a Baden tube or a bellows.

Preferably, the pressure sensor and the temperature sensor are an integrated structure; or, the integrated structure composed of the pressure sensor and the temperature sensor has a remote transmission function, remotely transmitting the monitored pressure value, temperature value, and/or gas density value, and/or remotely transmitting the contact signal of the gas density relay.

Preferably, the transmitter includes at least two pressure sensors, and the pressure values collected by the pressure sensors are compared to complete mutual verification between the pressure sensors.

Preferably, the transmitter includes at least two temperature sensors, and the temperature values collected by the temperature sensors are compared to complete mutual verification between the temperature sensors.

Preferably, the transmitter includes at least one pressure sensor and at least one temperature sensor; the pressure values collected by each pressure sensor and the temperature values collected by each temperature sensor are randomly arranged and combined, and each combination is converted into a plurality of pressure values corresponding to 20°C according to the gas pressure-temperature characteristics, that is, gas density values, and each gas density value is compared to complete the mutual verification of each pressure sensor and each temperature sensor; or, the pressure values collected by each pressure sensor and the temperature values collected by each temperature sensor are traversed through all arrangements and combinations, and each combination is converted into a plurality of pressure values corresponding to 20°C according to the gas pressure-temperature characteristics, that is, gas density values, and each gas density value is compared to complete the mutual verification of each pressure sensor and each temperature sensor; or, the multiple gas density values obtained by each pressure sensor and each temperature sensor are compared with the comparison density value output signal output by the gas density relay to complete the mutual verification of the gas density relay, each pressure sensor, and each temperature sensor; or, the multiple gas density values, pressure values, and temperature values obtained by each pressure sensor and each temperature sensor are compared to complete the mutual verification of the gas density relay, each pressure sensor, and each temperature sensor.

Preferably, the transmitter has a comparative density value output signal, which is connected to the intelligent control unit; or, the transmitter has a comparative pressure value output signal, which is connected to the intelligent control unit.

Preferably, the pressure regulating mechanism is a closed air chamber, and a heating element and/or a cooling element are provided outside or inside the closed air chamber. By heating the heating element and/or cooling by the cooling element, the temperature of the gas in the closed air chamber changes, thereby completing the pressure rise and fall of the gas density relay.

More preferably, the heating element and/or the cooling element is a semiconductor.

More preferably, the pressure regulating mechanism further comprises a heat-insulating component, and the heat-insulating component is arranged outside the closed air chamber.

Preferably, during calibration, the pressure regulating mechanism is a cavity with an opening at one end, and the other end of the cavity is connected to the gas path of the gas density relay; there is a piston in the cavity, one end of the piston 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, and the driving component drives the adjusting rod and thereby drives the piston to move in the cavity.

Preferably, during calibration, the pressure regulating mechanism is a closed air chamber, a piston is provided inside the closed air chamber, the piston is in sealing contact with the inner wall of the closed air chamber, and a driving component is provided outside the closed air chamber, and the driving component pushes the piston to move in the closed air chamber through electromagnetic force.

Preferably, the pressure regulating mechanism is an airbag with one end connected to a driving component, and the airbag changes in volume when driven by the driving component.

Preferably, the pressure regulating mechanism is a bellows, one end of the bellows is connected to the gas density relay, and the other end of the bellows is driven by a driving component to expand and contract.

The driving component in the above-mentioned pressure regulating mechanism includes, but is not limited to, one of a magnetic force, a motor (variable frequency motor or a stepping motor), a reciprocating motion mechanism, a Carnot cycle mechanism, and a pneumatic element.

Preferably, the pressure regulating mechanism is a vent valve.

More preferably, the pressure regulating mechanism further comprises a flow valve for controlling the gas release flow rate.

More preferably, the air release valve is a solenoid valve or an electric valve, or other air release valves realized by electrical or pneumatic means.

More preferably, the vent valve releases the gas to zero position, and the intelligent control unit collects the pressure value at that time, compares it, and completes the zero position calibration of the pressure sensor. The intelligent control unit determines the comparison result, and if the error exceeds the tolerance, an abnormal prompt is issued: there is a problem with the pressure sensor.

Preferably, the pressure regulating mechanism is a compressor.

Preferably, the pressure regulating mechanism is a pump, which includes but is not limited to a pressure-generating pump, a booster pump, an electric air pump or an electromagnetic air pump.

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

Preferably, the online calibration contact signal sampling unit is provided with at least two independent sampling contacts, which can automatically complete the calibration of at least two contacts of the gas density relay at the same time, and continuously measure without changing or reselecting contacts; wherein,

The contacts include, but are not limited to, one of an alarm contact, an alarm contact + a locking contact, an alarm contact + a locking contact 1 + a locking contact 2, and an alarm contact + a locking contact + an overpressure contact.

Preferably, the test voltage of the online verification contact signal sampling unit for the contact action value or the switching value (gas density value when the contact switches between open and closed states) of the gas density relay is not less than 24V, that is, during verification, a voltage of not less than 24V is applied between the corresponding terminals of the contact.

Preferably, the online verification contact signal sampling unit and the intelligent control unit are arranged in the housing of the transmitter.

Preferably, the online verification contact signal sampling unit and the intelligent control unit are arranged together.

More preferably, the online verification contact signal sampling unit and the intelligent control unit are sealed in a cavity or housing.

Preferably, the online verification contact signal sampling unit includes a first connection circuit and a second connection circuit; the first connection circuit connects the contact of the gas density relay and the contact signal control loop, and the second connection circuit connects the contact of the gas density relay and the intelligent control unit;

In the non-verification state, the contact is a normally open density relay, the second connection circuit is disconnected or isolated, and the first connection circuit is closed; in the verification state, the first connection circuit is disconnected, and the second connection circuit is connected, connecting the contact of the gas density relay to the intelligent control unit; or,

In the non-calibration state, the contact is a normally closed density relay, the second connection circuit is disconnected or isolated, and the first connection circuit is closed; in the calibration state, the contact signal control circuit is closed, the connection between the contact of the gas density relay and the contact signal control circuit is disconnected, and the second connection circuit is connected, connecting the contacts of the gas density relay to the intelligent control unit.

More preferably, the first connection circuit includes a first relay, the second connection circuit includes a second relay, the first relay is provided with at least one normally closed contact, the second relay is provided with at least one normally open contact, the normally closed contact and the normally open contact maintain opposite switch states; the normally closed contact is connected in series in the contact signal control loop, and the normally open contact is connected to the contact of the gas density relay;

In the non-calibration state, the normally closed contact is closed, the normally open contact is disconnected, and the gas density relay monitors the output state of the contact in real time; in the calibration state, the normally closed contact is disconnected, the normally open contact is closed, and the contact of the gas density relay is connected to the intelligent control unit through the normally open contact.

Furthermore, the first relay and the second relay are two independent relays, or are the same relay.

Preferably, the online verification contact signal sampling unit and the contacts of the gas density relay are isolated in circuit by photoelectric isolation.

Preferably, the communication mode of the communication module is wired communication or wireless communication.

More preferably, the wired communication method includes one or more of RS232 bus, RS485 bus, CAN-BUS bus, 4-20mA, Hart, IIC, SPI, Wire, coaxial cable, PLC power carrier, and cable.

More preferably, the wireless communication method includes one or more of a built-in 5G/NB-IOT communication module (such as 5G, NB-IOT) in the sensor, 2G/3G/4G/5G, WIFI, Bluetooth, Lora, Lorawan, Zigbee, infrared, ultrasonic, sound wave, satellite, light wave, quantum communication, and sonar.

Preferably, the transmitter further comprises a multi-way connector, and the gas density relay, the valve and the pressure regulating mechanism are arranged on the multi-way connector.

More preferably, the valve is embedded in the multi-way connector.

More preferably, the transmitter further comprises a self-sealing valve, and the self-sealing valve is mounted on the multi-way connector.

Preferably, the transmitter further comprises a trace water sensor, which is connected to the intelligent control unit and is used for online monitoring of the trace water value of the gas.

More preferably, the transmitter further comprises a gas circulation mechanism, the gas circulation mechanism is connected to the intelligent control unit, the gas circulation mechanism comprises a capillary, a sealed chamber and a heating element, and the gas flow is achieved by heating the heating element to monitor the gas micro-water value online. Preferably, the micro-water sensor can be installed in the sealed chamber of the gas circulation mechanism, in the capillary, at the capillary mouth, or outside the capillary.

Preferably, the transmitter further comprises a decomposition product sensor for online monitoring of gas decomposition products, and the decomposition product sensor is connected to the intelligent control unit.

Preferably, the transmitter further comprises a gas density relay, and the gas density relay comprises a digital or liquid crystal display device having a value display.

Preferably, the valve and the pressure regulating mechanism are connected together via a connecting pipe.

Preferably, the pressure sensor, the temperature sensor, the online calibration contact signal sampling unit, and the intelligent control unit are arranged in or on the housing of the gas density relay.

Preferably, the transmitter also includes a power supply for supplying power to each electrical device, and the power supply includes a power supply circuit, or a battery, or a rechargeable battery, or solar energy, or a power supply obtained by a transformer, or an inductive power supply.

Preferably, the transmitter is periodically set to perform online calibration of the gas density relay.

Preferably, when the gas density value or pressure value is lower than the set value, the transmitter automatically stops calibrating and sends out a warning signal.

Preferably, the transmitter is also provided with a temperature protection device for electronic components, so as to ensure that the electronic components can work reliably under low or high ambient temperature.

More preferably, the temperature protection device comprises a heater and/or a radiator (eg, a fan), the heater is turned on when the temperature is lower than a set value, and the radiator (eg, a fan) is turned on when the temperature is higher than a set value.

Preferably, the transmitter also includes an analysis system (eg, an expert management analysis system) for detecting, analyzing and determining the gas density value monitoring, the electrical performance of the gas density relay and the monitoring elements.

Preferably, the transmitter also includes a display interface for human-computer interaction, which displays current data in real time and/or supports data input, including real-time online gas density value display, pressure value display, temperature display, change trend analysis, historical data query, real-time alarm, etc.

Preferably, when the transmitter is calibrated at high temperature, low temperature, normal temperature, and 20° C. ambient temperature, the error determination requirements of the gas density relay are the same or different. Specifically, it can be implemented according to the temperature requirements and in accordance with relevant standards.

Preferably, the transmitter compares the error performance of the gas density relay at different temperatures and different time periods, that is, the comparison within the same temperature range at different periods is used to determine the performance of the gas density relay; there is a comparison of various historical periods and a comparison between history and the present.

Preferably, the transmitter has a self-diagnosis function and can promptly notify abnormalities, such as disconnection, short circuit alarm, sensor damage, and gas pressure rising trend.

Preferably, the transmitter also includes a camera for monitoring.

Preferably, the transmitter further comprises a shielding member capable of shielding the electric field and/or the magnetic field, and the shielding member is arranged inside or outside the housing of the transmitter; or,

The shielding member is disposed on the intelligent control unit and/or the communication module; or,

The shielding element is disposed on the pressure sensor.

Preferably, the transmitter displays the gas density value and the verification result locally, and/or displays the gas density value and the verification result through a remote background detection system.

Preferably, at least two of the transmitters are connected to the remote background detection system via a hub and a protocol converter in sequence.

More preferably, the hub is an RS485 hub.

More preferably, the protocol converter adopts an IEC61850 or IEC104 protocol converter.

More preferably, the protocol converter is also connected to a network service printer and a network data router respectively.

Preferably, the intelligent control unit of the transmitter is controlled through on-site control and/or through a remote background detection system.

More preferably, the intelligent control unit completes the online verification of the gas density relay according to the settings of the remote background detection system or the remote control instructions; or, completes the online verification of the gas density relay according to the set verification time of the gas density relay.

Preferably, the intelligent control unit is provided with a connection terminal for connecting to a density value output signal or a pressure value output signal of a gas density relay.

More preferably, when the gas density relay outputs a comparison density value output signal, the intelligent control unit collects the gas density value at that time, performs a comparison, completes the comparison density value verification of the gas density relay, and the intelligent control unit and/or the remote background detection system determine the comparison result, and if the error exceeds the tolerance, an abnormal prompt is issued; or,

When the gas density relay outputs a comparison density value output signal, the intelligent control unit collects the gas density value at that time, performs a comparison, and completes the mutual verification of the gas density relay and the temperature sensor and the pressure sensor. The intelligent control unit and/or the remote background detection system make a judgment on the comparison result. If the error exceeds the tolerance, an abnormal prompt is issued; or,

When the gas density relay outputs a comparison pressure value output signal, the intelligent control unit collects the pressure value at that time, performs a comparison, and completes the mutual verification of the gas density relay and the temperature sensor and the pressure sensor. The intelligent control unit and/or the remote background detection system make a judgment based on the comparison result. If the error exceeds the tolerance, an abnormal prompt is issued.

A third aspect of the present invention provides a method for implementing a transmitter for online calibration of a density relay, comprising:

During normal operation, the transmitter used for online calibration of the density relay monitors the gas density in the electrical equipment. At the same time, the transmitter transmits the pressure value, temperature value, and/or gas density value in the monitored electrical equipment over long distances through the pressure sensor, temperature sensor, and intelligent control unit.

The transmitter, based on the set calibration time and/or calibration instructions, as well as the gas density value, allows calibration of the gas density relay:

Adjust the pressure regulating mechanism to the initial state of calibration through the intelligent control unit (you can also skip this step and go directly to the next step);

Close the valve through the intelligent control unit;

The online verification contact signal sampling unit is adjusted to a verification state through the intelligent control unit. In the verification state, the online verification contact signal sampling unit cuts off the contact signal control loop of the gas density relay and connects the contacts of the gas density relay to the intelligent control unit.

The intelligent control unit drives the pressure regulating mechanism to slowly reduce the gas pressure, causing the gas density relay to have a contact action. The contact action is transmitted to the intelligent control unit through the online verification contact signal sampling unit. The intelligent control unit obtains the gas density value according to the pressure value and temperature value when the contact is in action, or directly obtains the gas density value, detects the contact action value of the gas density relay (the gas density value when the contact is in action), and completes the verification of the contact action value of the gas density relay;

When all the verification work is completed, the intelligent control unit opens the valve and adjusts the online verification contact signal sampling unit to the working state, and the contact signal control circuit of the gas density relay resumes the normal working state.

Preferably, the implementation method of the transmitter for online calibration of the density relay also includes:

When the transmitter completes the calibration of the contact action value of the gas density relay, and before the intelligent control unit opens the valve, the intelligent control unit drives the pressure regulating mechanism to slowly increase the gas pressure, so that the contacts of the gas density relay are reset. The contact reset is transmitted to the intelligent control unit through the online calibration contact signal sampling unit. The intelligent control unit obtains the gas density value according to the pressure value and temperature value at the time of contact reset, or directly obtains the gas density value, detects the contact return value of the gas density relay (gas density value at contact reset), and completes the calibration of the contact return value of the gas density relay.

Preferably, after the transmitter completes the calibration of the gas density relay, if there is any abnormality, the transmitter automatically issues an alarm, and/or uploads to a remote end, and/or sends to a designated receiver (for example, to a mobile phone).

Preferably, after the transmitter completes the calibration of the gas density relay, if there is any abnormality, the intelligent control unit uploads the alarm contact signal of the gas density relay to the remote end, and/or sends it to a designated receiver (for example, to a mobile phone) through a communication module.

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

1) Provide a transmitter for online calibration of density relays, including a housing, and a pressure sensor, a temperature sensor, a communication module, an intelligent control unit and a device connection joint arranged in the housing. The transmitter is connected to the electrical equipment and the gas density relay through the device connection joint; the transmitter also includes a valve, a pressure regulating mechanism and an online calibration contact signal sampling unit. The transmitter controls the pressure rise and fall of the pressure regulating mechanism through the intelligent control unit, so that the gas density relay has a contact action. The intelligent control unit detects the contact action value and/or return value of the gas density relay according to the density value when the contact is in action, and realizes remote transmission through the communication module to complete the calibration of the gas density relay. There is no need for maintenance personnel to go to the site for operation, and the electrical equipment is maintenance-free. The transmitter has a compact and reasonable layout, and the connection and disassembly of each part are easy to operate, which improves the reliability of the power grid, improves work efficiency and reduces costs.

2) Provide a monitoring system containing the above transmitter.

3) Provide a method for implementing a transmitter for online calibration of a density relay, which can support the normal operation of the above transmitter.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings that constitute part of this application are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an improper limitation on this application. In the drawings:

1 is a schematic diagram of the structure of a transmitter for online calibration of a density relay according to Embodiment 1;

2 is a schematic diagram of a control circuit of a transmitter for online calibration of a density relay according to Embodiment 2;

3 is a schematic diagram of the structure of a transmitter for online calibration of a density relay according to Embodiment 3;

4 is a schematic diagram of the structure of a transmitter for online calibration of a density relay according to a fourth embodiment;

5 is a schematic diagram of the structure of a transmitter for online calibration of a density relay according to Embodiment 5;

6 is a schematic diagram of the structure of a transmitter for online calibration of a density relay according to Embodiment 6;

7 is a schematic diagram of the structure of a transmitter for online calibration of a density relay according to Embodiment 7;

8 is a schematic structural diagram of a transmitter for online calibration of a density relay according to Embodiment 8;

9 is a schematic diagram of the structure of a transmitter for online calibration of a density relay according to Embodiment 9;

10 is a schematic diagram of the structure of a transmitter for online calibration of a density relay according to Embodiment 10;

11 is a schematic diagram of the structure of a transmitter for online calibration of a density relay according to Example 11;

12 is a schematic diagram of the structure of a transmitter for online calibration of a density relay according to Embodiment 12;

FIG13 is a schematic diagram of a control circuit of Embodiment 13;

FIG14 is a schematic diagram of a control circuit of Embodiment 14;

FIG15 is a schematic diagram of a control circuit of Embodiment 15;

FIG16 is a schematic diagram of a control circuit of Embodiment 16;

FIG17 is a schematic diagram of a control circuit of Embodiment 17;

FIG18 is a schematic diagram of a control circuit of Embodiment 18;

FIG19 is a schematic diagram of a control circuit of Embodiment 19;

FIG20 is a circuit diagram of a 4-20mA density transmitter;

21 is a schematic diagram of the structure of a transmitter for online calibration of a density relay according to Embodiment 21;

FIG22 is a schematic diagram of the architecture of a monitoring system according to Embodiment 22;

FIG23 is a schematic diagram of the architecture of a monitoring system according to Embodiment 23;

FIG. 24 is a schematic diagram of the architecture of a monitoring system according to Embodiment 24.

DETAILED DESCRIPTION

The present invention provides a transmitter for online calibration of density relays and a method and system for implementing the same. To make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

Embodiment 1:

FIG1 is a schematic diagram of the structure of a transmitter for online calibration of a density relay. As shown in FIG1 , it includes: a pressure sensor 2, a temperature sensor 3, a valve 4, a pressure regulating mechanism 5, an online calibration contact signal sampling unit 6, an intelligent control unit 7, a multi-way connector 9 and a gas supply interface 10. The transmitter is connected to the electrical equipment and the gas density relay 1 through the device connection connector. The gas density relay 1, the valve 4, the pressure sensor 2, the pressure regulating mechanism 5 and the gas supply interface 10 are arranged on the multi-way connector 9. Specifically, the air inlet of the valve 4 is provided with an interface connected to the electrical equipment, and the air inlet is sealed and connected to the electrical equipment and connected to the air chamber of the electrical equipment. The air outlet of the valve 4 is connected to the gas density relay 1 through a multi-way connector 9; the pressure sensor 2 is connected to the gas density relay 1 on the gas path through the multi-way connector 9; the pressure regulating mechanism 5 is connected to the gas density relay 1 through the multi-way connector 9; the online verification contact signal sampling unit 6 is respectively connected to the gas density relay 1 and the intelligent control unit 7; the valve 4, the pressure sensor 2, the temperature sensor 3 and the pressure regulating mechanism 5 are respectively connected to the intelligent control unit 7; the air supply interface 10 is connected to the multi-way connector 9.

Among them, the gas density relay 1 includes: a bimetallic compensated gas density relay, a gas compensated gas density relay, or a bimetallic and gas compensated mixed gas density relay; a fully mechanical gas density relay, a digital gas density relay, a mechanical and digital combined gas density relay; a density relay with an indication (a density relay with a pointer display, or a density relay with a digital display, a density relay with a liquid crystal display), a density relay without an indication (i.e., a density switch); a SF6 gas density relay, a SF6 mixed gas density relay, a N2 gas density relay, other gas density relays, and the like.

Types of pressure sensor 2: absolute pressure sensor, relative pressure sensor, or absolute pressure sensor and relative pressure sensor, the number can be several. The pressure sensor can be in the form of diffused silicon pressure sensor, MEMS pressure sensor, chip pressure sensor, coil induction pressure sensor (such as Baden tube with induction coil pressure measurement sensor), resistance pressure sensor (such as Baden tube with sliding wire resistance pressure measurement sensor), can be analog pressure sensor or digital pressure sensor. Pressure acquisition is a variety of pressure sensing elements such as pressure sensor, pressure transmitter, such as diffused silicon, sapphire, piezoelectric, strain gauge (resistance strain gauge, ceramic strain gauge).

The temperature sensor 3 can be: a thermocouple, a thermistor, a semiconductor type; it can be a contact type or a non-contact type; it can be a thermal resistor or a thermocouple. In short, temperature acquisition can be performed using various temperature sensing elements such as a temperature sensor, a temperature transmitter, etc.

The control of valve 4 can adopt a variety of transmission modes, such as manual, electric, hydraulic, pneumatic, turbine, electromagnetic, electromagnetic hydraulic, electro-hydraulic, gas-hydraulic, spur gear, bevel gear drive, etc.; it can act according to the predetermined requirements under the action of pressure, temperature or other forms of sensor signals, or simply open or close without relying on sensor signals. The valve relies on the 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 4 can be an automatic valve type, a power-driven valve type and a manual valve type according to the drive mode. The automatic valve 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, motor (motor) drive. The valve 4 can be automatic, manual or semi-automatic. The calibration process can be completed automatically or semi-automatically through manual cooperation. The valve 4 is directly or indirectly connected to the electrical equipment through a self-sealing valve, a manual valve, or a non-disassembly valve, and is connected in an integrated or separate manner. The valve 4 can be normally open or normally closed, one-way or two-way as required. In short, the gas circuit is opened or closed by the electric control valve. The electric control valve can be: solenoid valve, electric control ball valve, electric valve, electric control proportional valve, etc.

The pressure regulating mechanism 5 of this embodiment is a cavity with an opening at one end, a piston 51 is arranged in the cavity, the piston 51 is provided with a sealing ring 510, one end of the piston 51 is connected to an adjusting rod, the outer end of the adjusting rod is connected to a driving component 52, the other end of the piston 51 extends into the opening and contacts the inner wall of the cavity, the driving component 52 drives the adjusting rod and then drives the piston 51 to move in the cavity. The driving component 52 includes, but is not limited to, one of a magnetic force, a motor (variable frequency motor or stepper motor), a reciprocating motion mechanism, a Carnot cycle mechanism, and a pneumatic element.

The basic requirements or functions of the intelligent control unit 7 are: control of the valve 4, control of the pressure regulating mechanism 5 and signal acquisition are completed through the intelligent control unit 7. Realization: the pressure value and temperature value when the contact signal of the gas density relay 1 is actuated can be detected, and converted into the corresponding pressure value P ₂₀ (density value) at 20°C, that is, the contact action value _PD20 of the gas density relay 1 can be detected, and the calibration of the gas density relay 1 can be completed. Alternatively, the density value _PD20 when the contact signal of the gas density relay 1 is actuated can be directly detected to complete the calibration of the gas density relay 1.

Of course, the intelligent control unit 7 can also achieve: completing test data storage; and/or test data export; and/or test data printing; and/or data communication with the host computer; and/or inputting analog and digital information. The intelligent control unit 7 also includes a communication module, through which the long-distance transmission of test data and/or verification results and other information is realized; when the rated pressure value of the gas density relay 1 outputs a signal, the intelligent control unit 7 simultaneously collects the density value at that time to complete the rated pressure value verification of the gas density relay 1.

Electrical equipment, including 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 charging cabinets, ring main cabinets, etc.

The transmitter has the functions of pressure and temperature measurement and software conversion. Under the premise of not affecting the safe operation of electrical equipment, it can detect the alarm and/or locking contact action value and/or return value of the gas density relay 1 online. Of course, the return value of the alarm and/or locking contact signal can also be tested without testing according to requirements.

Embodiment 2:

Fig. 2 is a schematic diagram of a control circuit of a transmitter for online calibration of a density relay. As shown in Fig. 2, the online calibration contact signal sampling unit 6 of this embodiment is provided with a protection circuit, including a first connection circuit and a second connection circuit, wherein the first connection circuit connects the contact of the gas density relay 1 with the contact signal control loop, and the second connection circuit connects the contact of the gas density relay 1 with the intelligent control unit 7. In a non-calibration state, the second connection circuit is disconnected and the first connection circuit is closed; in a calibration state, the online calibration contact signal sampling unit 6 disconnects the first connection circuit, connects the second connection circuit, and connects the contact of the gas density relay 1 with the intelligent control unit 7.

Specifically, the first connection circuit includes a first relay J1, and the second connection circuit includes a second relay J2. The first relay J1 is provided with normally closed contacts J11 and J12, and the normally closed contacts J11 and J12 are connected in series in the contact signal control loop; the second relay J2 is provided with normally open contacts J21 and J22, and the normally open contacts J21 and J22 are connected to the contact _PJ of the gas density relay 1; it is also possible that the first relay J1 and the second relay J2 are combined into one, that is, a relay with normally open and normally closed contacts. In the non-verification state, the normally closed contacts J11 and J12 are closed, and the normally open contacts J21 and J22 are disconnected, and the gas density relay monitors the output state of the contact _PJ in real time; in the verification state, the normally closed contacts J11 and J12 are disconnected, and the normally open contacts J21 and J22 are closed, and the contact _PJ of the gas density relay 1 is connected to the intelligent control unit 7 through the normally open contacts J21 and J22.

The intelligent control unit 7 is mainly composed of a processor 71 (U1) and a power supply 72 (U2). The processor 71 (U1) can be a general-purpose computer, an industrial computer, a CPU, a single-chip microcomputer, an ARM chip, an AI chip, an MCU, an FPGA, a PLC, an industrial control mainboard, an embedded main control board, and other intelligent integrated circuits. The power supply 72 (U2) can be a switching power supply, an AC 220V, a DC power supply, an LDO, a programmable power supply, a solar energy, a storage battery, a rechargeable battery, a battery, and the like. The pressure sensor 2 of the pressure acquisition P can be: various pressure sensing elements such as a pressure sensor and a pressure transmitter. The temperature sensor 3 of the temperature acquisition T can be: various temperature sensing elements such as a temperature sensor and a temperature transmitter. The valve 4 can be: a solenoid valve, an electric valve, a pneumatic valve, a ball valve, a needle valve, a regulating valve, a gate valve, etc., which can open and close the gas path and even control the flow. Semi-automatic valves can also be manual valves. The pressure regulating mechanism 5 can be: an electric regulating piston, an electric regulating cylinder, a booster pump, a gas cylinder pressurization, as well as valves, solenoid valves, flow controllers, and the like. Semi-automatic pressure regulating mechanisms can also be manually adjusted.

The working principle of the first embodiment is as follows:

The intelligent control unit 7 monitors the gas pressure P and temperature T of the electrical equipment according to the pressure sensor 2 and the temperature sensor 3, and obtains the corresponding 20°C pressure value _P20 (i.e., the gas density value). When the gas density relay 1 needs to be verified, if the gas density value _P20 ≥ the set safety verification density value _Ps , the intelligent control unit 7 controls the closure of the valve 4, so that the gas density relay 1 is isolated from the electrical equipment in the gas path.

Next, the intelligent control unit 7 controls to disconnect the contact signal control loop of the gas density relay 1, that is, the normally closed contacts J11 and J12 of the first relay J1 of the online verification contact signal sampling unit 6 are disconnected, so that the safe operation of the electrical equipment will not be affected when the gas density relay 1 is verified online, and the alarm signal will not be mistakenly sent or the control loop will be locked during the verification. Because before the verification begins, the monitoring and judgment of the gas density value P ₂₀ ≥ the set safety verification density value P _S have been performed, the gas of the electrical equipment is within the safe operation range, and the gas leakage is a slow process, so it is safe during the verification. At the same time, the normally open contacts J21 and J22 of the second relay J2 of the online verification contact signal sampling unit 6 are closed, and at this time, the contact P _J of the gas density relay 1 is connected to the intelligent control unit 7 through the normally open contacts J21 and J22 of the second relay J2.

Then, the intelligent control unit 7 controls the driving component 52 of the pressure regulating mechanism 5 (which can be mainly realized by using a motor and a gear, and the method is diverse and flexible), and then adjusts the volume change of the pressure regulating mechanism 5, so that the pressure of the gas in the gas density relay 1 gradually decreases, so that the gas density relay 1 generates a contact signal action, and its contact signal action is uploaded to the intelligent control unit 7 through the second relay J2 of the online verification contact signal sampling unit 6. The intelligent control unit 7 converts the pressure value P and temperature T value measured when the contact signal is activated into a pressure value P ₂₀ (density value) corresponding to 20°C according to the gas characteristics, and can detect the contact action value _PD20 of the gas density relay. After all the contact signal action values of the alarm and/or locking signal of the gas density relay 1 are detected, the motor (motor, or variable frequency motor) of the pressure regulating mechanism 5 is controlled by the intelligent control unit 7, and the pressure regulating mechanism 5 is adjusted to gradually increase the pressure of the gas density relay 1, and the return value of the alarm and/or locking contact signal of the gas density relay 1 is tested. Repeat the calibration several times (for example, 2 to 3 times) and then calculate the average value, thus completing the calibration of the gas density relay.

After the verification is completed, the normally open contacts J21 and J22 of the second relay J2 of the online verification contact signal sampling unit 6 are disconnected. At this time, the contact _PJ of the gas density relay 1 is disconnected from the intelligent control unit 7 by disconnecting the normally open contacts J21 and J22 of the second relay J2. The intelligent control unit 7 controls the valve 4 to open, so that the gas density relay 1 is connected to the electrical equipment on the gas path. Then, the normally closed contacts J11 and J12 of the first relay J1 of the online verification contact signal sampling unit 6 are closed, the contact signal control circuit of the gas density relay 1 works normally, and the gas density relay safely monitors the gas density of the electrical equipment, so that the electrical equipment can work safely and reliably. In this way, it is convenient to complete the online verification of the gas density relay without affecting the safe operation of the electrical equipment.

When the transmitter completes the calibration work, the transmitter will make a judgment and can announce the test results. The method is flexible, specifically: 1) it can be announced on the spot, such as through indicator lights, digital or LCD displays; 2) or upload through online remote communication, such as uploading to the background monitoring terminal; 3) or upload wirelessly to a specific terminal, such as wirelessly uploading to a mobile phone; 4) or upload through other channels; 5) or upload abnormal results through an alarm signal line or a dedicated signal line; 6) upload alone, or upload with other signals. In short, after the transmitter completes the online calibration of the gas density relay 1, if there is an abnormality, it can automatically issue an alarm, which can be uploaded to the remote end, or can be sent to a designated receiver, such as to a mobile phone. Alternatively, after completing the calibration work, if there is an abnormality, the intelligent control unit 7 can upload the alarm contact signal of the gas density relay 1 to the remote end (monitoring room, background monitoring platform, etc.), and can also display the notice on the spot. The simple version of online calibration can upload the abnormal calibration results through the alarm signal line. It can be uploaded in a certain regularity. For example, when abnormal, a contact is connected in parallel to the alarm signal contact, and it is closed and disconnected regularly, and the status can be obtained through analysis; or it can be uploaded through an independent verification signal line. Specifically, it can be uploaded in good condition, or uploaded with problems, or the verification results can be uploaded through a separate verification signal line, or displayed on the spot, alarmed on the spot, or uploaded wirelessly, and uploaded through networking with a smartphone. Its communication mode is wired or wireless. The wired communication mode can be RS232, RS485, CAN-BUS and other industrial buses, optical fiber Ethernet, 4-20mA, Hart, IIC, SPI, Wire, coaxial cable, PLC power carrier, etc.; the wireless communication mode can be 2G/3G/4G/5G, WIFI, Bluetooth, Lora, Lorawan, Zigbee, infrared, ultrasonic, sound wave, satellite, light wave, quantum communication, sonar, sensor built-in 5G/NB-IOT communication module (such as NB-IOT), etc. In short, multiple modes and multiple combinations can be used to fully guarantee the reliable performance of the transmitter.

The transmitter has a safety protection function, that is, when it is lower than the set value, the transmitter will automatically stop online calibration of the gas density relay 1 and send out a warning signal. For example, when the gas density value is detected to be less than the set value _PS , it will no longer be calibrated; only when the gas density value is ≥ (alarm pressure value + 0.02MPa), can it be calibrated online.

The transmitter can be calibrated online according to the set time, or according to the set temperature (such as extreme high temperature, high temperature, extreme low temperature, low temperature, normal temperature, 20 degrees, etc.). When calibrating online at high temperature, low temperature, normal temperature, and 20°C ambient temperature, the error judgment requirements are different. For example, when calibrating at 20°C ambient temperature, the accuracy requirement of the gas density relay can be 1.0 or 1.6, and it can be 2.5 at high temperature. It can be implemented according to the temperature requirements and relevant standards. For example, according to Article 4.8 of the temperature compensation performance regulations in DL/T 259 "Calibration Procedure for Sulfur Hexafluoride Gas Density Relay", the accuracy requirements corresponding to each temperature value.

The transmitter can compare the error performance of the gas density relay 1 at different temperatures and different time periods. That is, the comparison within the same temperature range at different periods can determine the performance of the gas density relay 1 and electrical equipment, and can compare various historical periods and the historical and current periods.

The transmitter can be calibrated repeatedly for multiple times (for example, 2 to 3 times), and the average value can be calculated based on the calibration results of each time. If necessary, the gas density relay 1 can be calibrated online at any time.

When the transmitter completes the calibration of the gas density relay, it will automatically compare and judge each other. If the error difference is large, it will issue an abnormal prompt: there is a problem with the gas density relay or pressure sensor or temperature sensor. That is, the transmitter can complete the mutual calibration function of the gas density relay and the pressure sensor, temperature sensor, or density transmitter, and has artificial intelligence proofreading capabilities; after completing the calibration work, it can automatically generate a calibration report. If there is an abnormality, it can automatically issue an alarm or send it to a designated receiver, such as a mobile phone; the gas density value and calibration results can be displayed on-site, or through the background, and the specific method can be flexible; it has real-time online gas density value, pressure value, temperature value and other data display, change trend analysis, historical data query, real-time alarm and other functions; it can monitor the gas density value online, or the gas density value, pressure value, temperature value; it has a self-diagnosis function, and can promptly notify abnormalities, such as disconnection, short circuit alarm, sensor damage and other notifications; it can compare the error performance of the gas density relay at different temperatures and different time periods. That is, the comparison in different periods and the same temperature range can determine the performance of the gas density relay. It can compare various periods in history and compare history with the present. It can judge, analyze and compare the normal and abnormal gas density value of the electrical equipment itself, gas density relay 1, pressure sensor 2 and temperature sensor 3. It also contains an analysis system (expert management analysis system) to detect, analyze and judge the gas density value monitoring, gas density relay and monitoring elements to know where the problem is. It also monitors the contact signal status of the gas density relay 1 and transmits its status remotely. You can know whether the contact signal status of the gas density relay 1 is open or closed in the background, so as to have an extra layer of monitoring and improve reliability. It can also detect, or detect and judge the temperature compensation performance of the gas density relay 1. It can also detect, or detect and judge the contact resistance of the gas density relay 1. It has data analysis and data processing functions and can perform corresponding fault diagnosis and prediction on electrical equipment.

As long as the test data of pressure sensor 2, temperature sensor 3, and gas density relay 1 are consistent and normal, it can be said that the gas density relay is normal, so there is no need to calibrate the gas density relay, nor to calibrate other devices, and the whole life can be free of calibration. Unless the test data of pressure sensor 2, temperature sensor 3, and gas density relay 1 of a certain electrical equipment in the substation are inconsistent and abnormal, maintenance personnel will be arranged to deal with it. For consistent and normal situations, there is no need to calibrate, which greatly improves reliability, efficiency, and reduces costs.

Embodiment three:

As shown in FIG. 3 , the transmitter for online calibration of the density relay includes: a pressure sensor 2 , a temperature sensor 3 , a valve 4 , a pressure regulating mechanism 5 , an online calibration contact signal sampling unit 6 and an intelligent control unit 7 .

The air inlet of the valve 4 is sealed and connected to the electrical equipment through the electrical equipment connection joint 1010, and the air outlet of the valve 4 is connected to the base and pressure detector of the gas density relay 1. The pressure sensor 2, the temperature sensor 3, the online verification contact signal sampling unit 6, and the intelligent control unit 7 are arranged on or in the housing of the gas density relay 1. The pressure sensor 2 is connected to the pressure detector of the gas density relay 1 on the gas path; the pressure regulating mechanism 5 is connected to the pressure detector of the gas density relay 1; the online verification contact signal sampling unit 6 and the intelligent control unit 7 are arranged together. The pressure sensor 2, the temperature sensor 3, the valve 4, and the pressure regulating mechanism 5 are respectively connected to the intelligent unit 7.

The pressure is adjusted by the pressure regulating mechanism 5, so that the signal generator of the gas density relay 1 generates contact action, and the contact action is transmitted to the intelligent control unit 7 through the online verification contact signal sampling unit 6. The intelligent control unit 7 detects the alarm and/or locking contact signal action value and/or return value of the gas density relay according to the gas density value when the gas density relay 1 generates contact action, or according to the pressure value and temperature value converted into the corresponding gas density value, and completes the calibration of the gas density relay. Or as long as the alarm and/or locking contact action value is detected, the calibration of the gas density relay is completed.

Embodiment 4:

As shown in Fig. 4, this embodiment adds a gas supply interface 10 and a self-sealing valve 11 compared with the third embodiment. One end of the self-sealing valve 11 is sealed and connected to the electrical device, and the other end of the self-sealing valve 11 is connected to the gas inlet of the valve 4 and the gas supply interface 10 through a connecting pipe.

Embodiment five:

As shown in FIG5 , a transmitter for online calibration of a density relay includes: a pressure sensor 2, a temperature sensor 3, a valve 4, a pressure regulating mechanism 5, an online calibration contact signal sampling unit 6 and an intelligent control unit 7. The air inlet of the valve 4 is sealed and connected to the electrical equipment through an electrical equipment connection joint, and the air outlet of the valve 4 is connected to the base of the gas density relay 1, the pressure sensor 2, and the pressure regulating mechanism 5. The pressure sensor 2, the temperature sensor 3, the valve 4, and the pressure regulating mechanism 5 are arranged on the rear side of the housing of the gas density relay 1. The online calibration contact signal sampling unit 6 and the intelligent control unit 7 are arranged on the electrical equipment connection joint. The pressure sensor 2 is connected to the pressure detector of the gas density relay 1 on the gas path through the base of the gas density relay 1; the pressure regulating mechanism 5 is connected to the pressure detector of the gas density relay 1. The pressure sensor 2, the temperature sensor 3, the valve 4, and the pressure regulating mechanism 5 are respectively connected to the intelligent control unit 7. Different from the first embodiment, the pressure sensor 2, the temperature sensor 3, the valve 4, and the pressure regulating mechanism 5 are arranged on the rear side of the housing of the gas density relay 1.

Embodiment six:

As shown in FIG6 , a transmitter for online calibration of a density relay comprises: a pressure sensor 2, a temperature sensor 3, a valve 4, a pressure regulating mechanism 5, an online calibration contact signal sampling unit 6 and an intelligent control unit 7. The air inlet of the valve 4 is sealed and connected to the electrical equipment through an electrical equipment connection joint, the air outlet of the valve 4 is connected to a connecting pipe, the connecting pipe is connected to the pressure detector of the gas density relay 1, and the pressure sensor 2 and the pressure regulating mechanism 5 are also connected to the connecting pipe, so that the valve 4, the pressure sensor 2, the pressure regulating mechanism 5 and the pressure detector are connected in the gas path. The gas density relay 1, the pressure sensor 2, the temperature sensor 3, the valve 4, the pressure regulating mechanism 5, the online calibration contact signal sampling unit 6 and the intelligent control unit 7 are arranged in a housing; the online calibration contact signal sampling unit 6 and the intelligent control unit 7 are arranged together. The pressure sensor 2 and the temperature sensor 3 are directly or indirectly connected to the intelligent control unit 7; the valve 4 and the pressure regulating mechanism 5 are respectively connected to the intelligent control unit 7.

Embodiment seven:

As shown in FIG7 , a transmitter for online calibration of a density relay includes: a pressure sensor 2, a temperature sensor 3, a valve 4, a pressure regulating mechanism 5, an online calibration contact signal sampling unit 6, and an intelligent control unit 7. The air inlet of the valve 4 is sealed and connected to the electrical equipment through an electrical equipment connection joint, and the air outlet of the valve 4 is connected to the pressure detector of the gas density relay 1. The gas density relay 1, the temperature sensor 3, the online calibration contact signal sampling unit 6 and the intelligent control unit 7 are arranged together. The pressure sensor 2 is connected to the pressure detector of the gas density relay 1 on the gas path; the pressure regulating mechanism 5 is connected to the pressure detector of the gas density relay 1 on the gas path. The pressure sensor 2, the temperature sensor 3, the valve 4, and the pressure regulating mechanism 5 are respectively connected to the intelligent control unit 7.

Different from the first embodiment, the pressure regulating mechanism 5 of this embodiment is mainly composed of an airbag 53 and a driving component 52. Under the control of the intelligent control unit 7, the pressure regulating mechanism 5 causes the driving component 52 to push the airbag 53 to change its volume, thereby completing the pressure rise and fall.

Embodiment eight:

As shown in Fig. 8, a transmitter for online calibration of density relays includes: a pressure sensor 2, a temperature sensor 3, a valve 4, a pressure regulating mechanism 5, an online calibration contact signal sampling unit 6, an intelligent control unit 7, and a multi-way connector 9. The air inlet of the valve 4 is sealed and connected to the equipment connection connector, and the air outlet of the valve 4 is connected to the multi-way connector 9. The gas density relay 1 is installed on the multi-way connector 9; the pressure sensor 2 is installed on the multi-way connector 9, and the pressure sensor 2 is connected to the pressure detector of the gas density relay 1 on the gas path; the pressure regulating mechanism 5 is installed on the multi-way connector 9, and the pressure regulating mechanism 5 is connected to the pressure detector of the gas density relay 1; the temperature sensor 3, the online calibration contact signal sampling unit 6 and the intelligent control unit 7 are arranged together and arranged on the multi-way connector 9; the pressure sensor 2, the temperature sensor 3, the valve 4, and the pressure regulating mechanism 5 are respectively connected to the intelligent control unit 7.

The difference from the first embodiment is that the pressure regulating mechanism 5 of this embodiment is mainly composed of a bellows 54 and a driving component 52. The bellows 54 is sealed and connected to the pressure detector of the gas density relay 1 to form a reliable sealed cavity. According to the control of the intelligent control unit 7, the pressure regulating mechanism 5 causes the driving component 52 to push the bellows 54 to change in volume, and then the sealed cavity changes in volume, thereby completing the rise and fall of pressure. The pressure is adjusted by the pressure regulating mechanism 5, so that the gas density relay 1 has a contact action, and the contact action is transmitted to the intelligent control unit 7 through the online verification contact signal sampling unit 6. The intelligent control unit 7 converts the pressure value and temperature value of the gas density relay 1 when the contact is in action into the corresponding density value, detects the alarm and/or locking contact action value and/or return value of the gas density relay 1, and completes the verification of the gas density relay 1.

Embodiment nine:

As shown in FIG9 , a transmitter for online calibration of a density relay includes: a pressure sensor 2, a temperature sensor 3, a valve 4, a pressure regulating mechanism 5, an online calibration contact signal sampling unit 6, and an intelligent control unit 7. The air inlet of the valve 4 is sealed and connected to the electrical equipment through an electrical equipment connection joint, and the air outlet of the valve 4 is connected to the pressure detector of the gas density relay 1. The pressure sensor 2 and the temperature sensor 3 are arranged on the gas density relay 1, and the pressure sensor 2 is connected to the pressure detector of the gas density relay 1 on the gas path. The pressure regulating mechanism 5 is connected to the pressure detector of the gas density relay 1. The pressure sensor 2, the temperature sensor 3, the valve 4, and the pressure regulating mechanism 5 are respectively connected to the intelligent control unit 7.

The difference from the first embodiment is that the valve 4 is sealed inside the first housing 41, and the control cable of the valve 4 is led out through the first lead-out seal 42 sealed with the first housing 41. This design ensures that the valve 4 remains sealed and can work reliably for a long time. The pressure regulating mechanism 5 is sealed inside the second housing 55, and the control cable of the pressure regulating mechanism 5 is led out through the second lead-out seal 56 sealed with the second housing 55. This design ensures that the pressure regulating mechanism 5 remains sealed and can work reliably for a long time. The second housing 55 and the first housing 41 can also be combined into one.

Embodiment ten:

As shown in FIG10 , a transmitter for online calibration of a density relay includes: a pressure sensor 2, a temperature sensor 3, a valve 4, a pressure regulating mechanism 5, an online calibration contact signal sampling unit 6, and an intelligent control unit 7. The air inlet of the valve 4 is sealed and connected to the electrical equipment through an electrical equipment connection joint, the air outlet of the valve 4 is connected to the pressure regulating mechanism 5, and the pressure sensor 2 is arranged on the pressure regulating mechanism 5. The temperature sensor 3, the online calibration contact signal sampling unit 6, the intelligent control unit 7, and the gas density relay 1 are arranged on the pressure regulating mechanism 5. The pressure detector, the pressure sensor 2, the pressure regulating mechanism 5, and the valve 4 of the gas density relay 1 are connected in the gas path. The temperature sensor 3, the online calibration contact signal sampling unit 6, and the intelligent control unit 7 are arranged together. The pressure sensor 2, the temperature sensor 3, the valve 4, and the pressure regulating mechanism 5 are respectively connected to the intelligent control unit 7.

Embodiment eleven:

As shown in FIG11 , a transmitter for online calibration of a density relay comprises: a first pressure sensor 21, a second pressure sensor 22, a first temperature sensor 31, a second temperature sensor 32, a valve 4, a pressure regulating mechanism 5, an online calibration contact signal sampling unit 6, and an intelligent control unit 7. The air inlet of the valve 4 is sealed and connected to the electrical equipment through an electrical equipment connection joint, and the air outlet of the valve 4 is connected to the pressure regulating mechanism 5. The gas density relay 1, the first temperature sensor 31, the online calibration contact signal sampling unit 6, and the intelligent control unit 7 are arranged together and arranged on the pressure regulating mechanism 5; the first pressure sensor 21 is arranged on the pressure regulating mechanism 5. The second pressure sensor 22 and the second temperature sensor 32 are arranged on the side where the valve 4 is connected to the electrical connection joint. The first pressure sensor 21 and the pressure detector of the gas density relay 1 are connected to the pressure regulating mechanism 5 on the gas path; the first pressure sensor 21, the second pressure sensor 22, the first temperature sensor 31, and the second temperature sensor 32 are connected to the intelligent control unit 7; the valve 4 and the pressure regulating mechanism 5 are respectively connected to the intelligent control unit 7.

Different from the first embodiment, there are two pressure sensors, namely the first pressure sensor 21 and the second pressure sensor 22; there are two temperature sensors, namely the first temperature sensor 31 and the second temperature sensor 32. The second temperature sensor 32 can also be omitted in this embodiment. This embodiment has a plurality of pressure sensors and temperature sensors, and the pressure values monitored by the plurality of pressure sensors can be compared and mutually verified; the temperature values obtained by the plurality of temperature sensors can be compared and mutually verified; the corresponding plurality of gas density values monitored by the plurality of pressure sensors and the plurality of temperature sensors can be compared and mutually verified.

Embodiment 12:

As shown in FIG12 , a transmitter for online calibration of a density relay comprises: a pressure sensor 2, a temperature sensor 3, a valve 4, a pressure regulating mechanism 5, an online calibration contact signal sampling unit 6, an intelligent control unit 7, and a multi-way connector 9. The air inlet of the valve 4 is sealed and connected to the upper portion of the electrical device, and the air outlet of the valve 4 is connected to the multi-way connector 9. The valve 4 is sealed inside the first housing 41, and the control cable of the valve 4 is led out through the first lead-out seal 42 sealed with the first housing 41. This design ensures that the valve 4 remains sealed and can work reliably for a long time. The gas density relay 1 is mounted on the multi-way connector 9; the pressure regulating mechanism 5 is mounted on the multi-way connector 9. The pressure sensor 2, the temperature sensor 3, the online calibration contact signal sampling unit 6 and the intelligent control unit 7 are arranged on the gas density relay 1. The pressure sensor 2 and the gas density relay 1 are connected to the pressure regulating mechanism 5 on the gas path. The valve 4, the pressure regulating mechanism 5, the pressure sensor 2, and the temperature sensor 3 are respectively connected to the intelligent control unit 7.

What is different from the first embodiment is that the pressure sensor 2, the temperature sensor 3, the online verification contact signal sampling unit 6 and the intelligent control unit 7 are arranged on the gas density relay 1. The pressure regulating mechanism 5 of this embodiment is mainly composed of an air chamber 57, a heating element 58 and a heat preservation member 59. The air chamber 57 is provided with a heating element 58 on the outside (or inside), and the heating causes the temperature to change, thereby completing the pressure rise and fall. The pressure is adjusted by the pressure regulating mechanism 5, so that the gas density relay 1 has a contact action, and the contact action is transmitted to the intelligent control unit 7 through the online verification contact signal sampling unit 6. The intelligent control unit 7 converts the pressure value and temperature value of the gas density relay 1 when the contact is in action into the corresponding density value, detects the alarm and/or locking contact action value and/or return value of the gas density relay, and completes the calibration of the gas density relay.

The working principle of this embodiment is as follows: when it is necessary to calibrate the density relay, the intelligent control unit 7 controls the heating element 58 of the pressure regulating mechanism 5 to heat it. When the temperature difference between the temperature value T510 in the pressure regulating mechanism 5 and the temperature value T of the temperature sensor 3 reaches the set value, the valve 4 can be closed by the intelligent control unit 7 to isolate the gas density relay from the electrical equipment in the gas path; then the heating element 58 of the regulating mechanism 5 is immediately turned off, and the heating of the heating element 58 is stopped. The pressure of the gas in the closed gas chamber 57 of the pressure regulating mechanism 5 gradually decreases, causing the gas density relay 1 to alarm and/or lock contacts to act respectively, and its contact action is transmitted to the intelligent control unit 7 through the online verification contact signal sampling unit 6. The intelligent control unit 7 detects the alarm and/or lock contact action value and/or return value of the gas density relay according to the density value when the alarm and/or lock contacts are actuated, and completes the calibration of the gas density relay.

Embodiment 13:

As shown in Figure 13, the online verification contact signal sampling unit 6 of this embodiment includes a photocoupler OC1 and a resistor R1, and the photocoupler OC1 includes a light emitting diode and a phototransistor; the anode of the light emitting diode and the contact _PJ of the gas density relay 1 are connected in series to form a closed loop; the emitter of the phototransistor is grounded; the collector of the phototransistor is connected to the intelligent control unit 7 as the output end out6 of the online verification contact signal sampling unit 6, and the collector of the phototransistor is also connected to the power supply through the resistor R1.

Through the above circuit, it is convenient to know whether the contact _PJ of the gas density relay 1 is open (non-action state) or closed (action state). Specifically, when the contact _PJ is closed, the closed loop is energized, the light-emitting diode emits light, the light turns on the phototransistor, and the collector of the phototransistor outputs a low level; when the contact _PJ is disconnected, the closed loop is disconnected, the light-emitting diode does not emit light, the phototransistor is turned off, and the collector of the phototransistor outputs a high level. In this way, the output end out6 of the online verification contact signal sampling unit 6 outputs high and low levels.

This embodiment isolates the intelligent control unit 7 from the contact signal control circuit by means of photoelectric isolation. The contact _PJ is closed during the verification process, or the contact _PJ is also closed in the event of a gas leak. At this time, the low level output by the collector of the phototransistor is detected. The time for closing the contact _PJ during the verification process is controlled to be a preset length, so that the duration of the closed state of the contact _PJ during the verification process in the absence of a gas leak is determined. By monitoring the duration of the received low level, it can be determined whether the contact _PJ is closed during the verification process. Therefore, during the verification, it can be determined by recording the time that the gas density relay 1 sends an alarm signal during the verification, rather than an alarm signal during a gas leak.

In this embodiment, the intelligent control unit 7 is mainly composed of a processor 71 (U1) and a power supply 72 (U2).

Embodiment 14:

As shown in FIG. 14 , the online verification contact signal sampling unit 6 of this embodiment includes a first photoelectric coupler OC1 and a second photoelectric coupler OC2 .

The light-emitting diode of the first photocoupler OC1 and the light-emitting diode of the second photocoupler OC2 are respectively connected in parallel through current-limiting resistors, and are connected in series with the contacts of the gas density relay after parallel connection to form a closed loop, and the connection directions of the light-emitting diodes of the first photocoupler OC1 and the second photocoupler OC2 are opposite; the collector of the phototransistor of the first photocoupler OC1 and the collector of the phototransistor of the second photocoupler OC2 are both connected to the power supply through a voltage-dividing resistor, and the emitter of the phototransistor of the first photocoupler OC1 and the emitter of the phototransistor of the second photocoupler OC2 are connected to form an output terminal out6, and the output terminal out6 is connected to the intelligent control unit 7 and grounded through a resistor R5.

Through the above circuit, it is convenient to know whether the contact _PJ of the gas density relay 1 is open (non-action state) or closed (action state). Specifically, when the contact _PJ is closed, the closed loop is energized, the first photocoupler OC1 is turned on, the second photocoupler OC2 is turned off, and the emitter of the phototransistor of the first photocoupler OC1 (i.e., the output end out6) outputs a high level; or, the first photocoupler OC1 is turned off, the second photocoupler OC2 is turned on, and the emitter of the phototransistor of the second photocoupler OC2 (i.e., the output end out6) outputs a high level. When the contact _PJ is disconnected, the closed loop is de-energized, the first photocoupler OC1 and the second photocoupler OC2 are both turned off, and the emitters of the phototransistors of the first photocoupler OC1 and the second photocoupler OC2 (i.e., the output end out6) output a low level.

In a preferred embodiment, the circuit also includes a first Zener diode group and a second Zener diode group, the first Zener diode group and the second Zener diode group are connected in parallel on the contact signal control loop, and the connection directions of the first Zener diode group and the second Zener diode group are opposite; the first Zener diode group and the second Zener diode group are each composed of one, two or more Zener diodes connected in series.

In this embodiment, the first Zener diode group includes a first Zener diode D1 and a second Zener diode D2 connected in series, and the cathode of the first Zener diode D1 is connected to the anode of the second Zener diode D2; the second Zener diode group includes a third Zener diode D3 and a fourth Zener diode D4 connected in series, and the anode of the third Zener diode D3 is connected to the cathode of the fourth Zener diode D4.

The above circuit can conveniently monitor the state of the contact _PJ of the gas density relay 1. Combined with the intelligent control unit 7, the contact _PJ is processed accordingly to determine whether it is in an open state or a closed state, and remote transmission is implemented. The contact signal state is known from the background, which greatly improves the reliability of the power grid.

In this embodiment, the intelligent control unit 7 is mainly composed of a processor 71 (U1) and a power supply 72 (U2).

Embodiment 15:

As shown in FIG. 15 , the difference between this embodiment and the fourteenth embodiment is that the intelligent control unit 7 is mainly composed of a processor 71 (U1), a power supply 72 (U2), a communication module 73 (U3), an intelligent control unit protection circuit 74 (U4), a display and output 75 (U5), a data storage 76 (U6), etc.

The communication mode of the communication module 73 (U3) can be wired, such as industrial buses such as RS232, RS485, CAN-BUS, optical fiber Ethernet, 4-20mA, Hart, IIC, SPI, Wire, coaxial cable, PLC power carrier, etc.; or wireless, such as 2G/3G/4G/5G, WIFI, Bluetooth, Lora, Lorawan, Zigbee, infrared, ultrasonic, sound wave, satellite, light wave, quantum communication, sonar, etc. The intelligent control unit protection circuit 74 (U4) can be an anti-static interference circuit (such as ESD, EMI), an anti-surge circuit, an electric fast protection circuit, an anti-radio frequency interference circuit, an anti-pulse group interference circuit, a power short circuit protection circuit, a power reverse connection protection circuit, an electrical contact misconnection protection circuit, a charging protection circuit, etc. These intelligent control unit protection circuits can be one or a combination of several. Display and output 75 (U5) can be digital tube, LED, LCD, HMI, display, matrix screen, printer, fax, projector, mobile phone, etc., and can be one or several flexible combinations. Data storage 76 (U6) can be FLASH, RAM, ROM, hard disk, SD and other flash memory cards, magnetic tape, punched paper tape, optical disk, U disk, disk, film, etc., and can be one or several flexible combinations.

Embodiment 16:

As shown in Figure 16, the online verification contact signal sampling unit 6 of this embodiment includes a first Hall current sensor H1 and a second Hall current sensor H2. The first Hall current sensor H1, the second Hall current sensor H2 and the contact _PJ of the gas density relay are connected in series to form a closed loop, and the contact _PJ of the gas density relay 1 is connected between the first Hall current sensor H1 and the second Hall current sensor H2; the output end of the first Hall current sensor H1 and the output end of the second Hall current sensor H2 are both connected to the intelligent control unit 7.

Through the above circuit, it is convenient to know whether the contact _PJ of the gas density relay 1 is open (non-operating state) or closed (operating state). Specifically, when the contact _PJ is closed, the closed loop is energized, and current flows between the first Hall current sensor H1 and the second Hall current sensor H2, generating an induced potential; when the contact _PJ is disconnected, the closed loop is de-energized, and no current flows between the first Hall current sensor H1 and the second Hall current sensor H2, and the generated induced potential is zero.

In this embodiment, the intelligent control unit 7 is mainly composed of a processor 71 (U1), a power supply 72 (U2), a communication module 73 (U3), an intelligent control unit protection circuit 74 (U4), a display and output 75 (U5), a data storage 76 (U6), etc.

Embodiment 17:

As shown in FIG. 17 , the online verification contact signal sampling unit 6 of this embodiment includes a first thyristor SCR1 , a second thyristor SCR2 , a third thyristor SCR3 and a fourth thyristor SCR4 .

The first thyristor SCR1 and the third thyristor SCR3 are connected in series, and the second thyristor SCR2 and the fourth thyristor SCR4 are connected in series to form a series-parallel closed loop with the series circuit composed of the first thyristor SCR1 and the third thyristor SCR3; one end of the contact _PJ of the gas density relay 1 is electrically connected to the circuit between the first thyristor SCR1 and the third thyristor SCR3 through the circuit, and the other end is electrically connected to the circuit through the circuit

The circuits between the second thyristor SCR2 and the fourth thyristor SCR4 are electrically connected. The series-parallel connection described here is shown in FIG6 , which is a circuit in which the above components are connected in parallel or in series.

Specifically, the cathode of the first thyristor SCR1 and the cathode of the second thyristor SCR2 are connected to form the output end of the online verification contact signal sampling unit 6 and connected to the intelligent control unit 7; the anode of the first thyristor SCR1 is connected to the cathode of the third thyristor SCR3; the anode of the second thyristor SCR2 is connected to the cathode of the fourth thyristor SCR4; the anode of the third thyristor SCR3 and the anode of the fourth thyristor SCR4 are connected to the input end of the online verification contact signal sampling unit 6. Among them, the control electrodes of the first thyristor SCR1, the second thyristor SCR2, the third thyristor SCR3 and the fourth thyristor SCR4 are all connected to the intelligent control unit 7. The intelligent control unit 7 can control the on or off of the corresponding thyristor.

The working process of this embodiment is as follows:

When no verification is performed and the system operates normally, the contact P _J is disconnected, triggering the third thyristor SCR3 and the fourth thyristor SCR4, the third thyristor SCR3 and the fourth thyristor SCR4 are in the on state, and the contact signal control loop is in the working state. At this time, the first thyristor SCR1 and the second thyristor SCR2 are not triggered, and the cathodes of the first thyristor SCR1 and the second thyristor SCR2 have no voltage output and are in the off state. When verification is performed, the third thyristor SCR3 and the fourth thyristor SCR4 are not triggered, but the first thyristor SCR1 and the second thyristor SCR2 are triggered. At this time, the third thyristor SCR3 and the fourth thyristor SCR4 are in the off state, and the contact P _J is isolated from the contact signal control loop. The first thyristor SCR1 and the second thyristor SCR2 are in the on state, and the contact P _J is connected to the online verification contact signal sampling unit 6 and connected to the intelligent control unit 7. The online verification contact signal sampling unit 6 can also be composed of a solid-state relay or an electromagnetic relay and a thyristor in a flexible manner.

In this embodiment, the intelligent control unit 7 is mainly composed of a processor 71 (U1), a power supply 72 (U2), a communication module 73 (U3), an intelligent control unit protection circuit 74 (U4), a display and output 75 (U5), a data storage 76 (U6), etc.

Embodiment 18:

As shown in FIG18 , the intelligent control unit 7 is mainly composed of a processor 71 (U1), a power supply 72 (U2), a communication module 73 (U3), an intelligent control unit protection circuit 74 (U4), a display and output and operation 75 (U5), and a data storage 76 (U6). The processor 71 (U1) contains a crystal oscillator and a filter circuit. The intelligent control unit protection circuit 74 (U4) includes a surge protection circuit, a filter circuit, a short circuit protection circuit, a polarity protection circuit, an overvoltage protection circuit, etc. The power supply has two levels and also includes a step-down module.

The communication mode of the communication module 73 (U3) can be wired: such as RS232, RS485, CAN-BUS and other industrial buses, optical fiber Ethernet, 4-20mA, Hart, IIC, SPI, Wire, coaxial cable, PLC power carrier, etc.; or wireless: such as 2G/3G/4G/5G, WIFI, Bluetooth, Lora, Lorawan, Zigbee, infrared, ultrasonic, sound wave, satellite, light wave, quantum communication, sonar, etc. The display and output 75 (U5) can be: digital tube, LED, LCD, HMI, display, matrix screen, printer, fax, projector, mobile phone, etc., which can be flexibly combined by one or several kinds. The data storage 76 (U6) can be: FLASH, RAM, ROM, hard disk, SD and other flash memory cards, magnetic tape, punched paper tape, optical disk, U disk, disk, film, etc., which can be flexibly combined by one or several kinds.

Embodiment 19:

As shown in Figure 19, the intelligent control unit 7 is mainly composed of a processor 71 (U1), a power supply 72 (U2), a communication module 73 (U3), an intelligent control unit protection circuit 74 (U4), etc. The processor 71 (U1) contains a crystal oscillator and a filter circuit. The intelligent control unit protection circuit 74 (U4) includes a surge protection circuit, a filter circuit, a short circuit protection circuit, a polarity protection circuit, an overvoltage protection circuit, etc. The power supply has two levels and also includes a step-down module. The pressure sensor 2 passes through the overvoltage protection circuit, the operational amplifier circuit, and the modulation circuit, and then passes through the filter circuit to the processor 71 (U1). In the communication module 73 (U3), the communication chip passes through the surge protection circuit to the communication interface.

Embodiment 20:

Figure 20 is a circuit diagram of a 4-20mA density transmitter. As shown in Figure 20, the 4-20mA density transmitter is mainly composed of a microprocessor (including a main controller, a crystal oscillator and a filter circuit), a power supply, a modulation circuit, a current loop, a protection circuit, an analog pressure sensor, an operational amplifier, a temperature sensor, a proportional modulation module, a step-down module, etc. The microprocessor contains a crystal oscillator and a filter circuit. The protection circuit includes a surge protection circuit, a filter circuit, a short circuit protection circuit, a polarity protection circuit, an overvoltage protection circuit, etc. The analog pressure sensor passes through the overvoltage protection circuit, the operational amplifier circuit, and then to the modulation circuit, and then to the microprocessor through the filter circuit, so that the microprocessor can collect the pressure value and the temperature value, and obtain the density value signal after calculation and conversion by the microprocessor. The density value signal passes through the proportional modulation module, the modulation circuit, and the current loop to obtain the 4-20mA density value.

In short, the analog pressure sensor, temperature sensor, and micro-water sensor are converted to A/D and sent to MCU after passing through the amplification circuit to realize pressure, temperature, and moisture collection. The intelligent control unit 7 can contain or connect to a printer, a liquid crystal display, and can also realize USB storage and RS232 communication.

Embodiment 21:

FIG21 is a schematic diagram of the structure of a transmitter for online calibration of a density relay according to the twenty-first embodiment of the present application. As shown in FIG21 , the transmitter includes: a pressure sensor 2, a temperature sensor 3, a valve 4, a pressure regulating mechanism 5, an online calibration contact signal sampling unit 6, and an intelligent control unit 7. The intelligent control unit 7 includes: a processor 71 (U1), a power supply 72 (U2), a communication module 73 (U3), an intelligent control unit protection circuit 74 (U4), a valve controller 77 (U7), an execution controller 78 (U8), a human-machine interface 79 (U9), a pressure regulating mechanism position detection component 511, etc. The execution controller 78 (U8) can also be called a control system, which can be set on the intelligent control unit 7; or some components of the control system are set on the pressure regulating mechanism 5, and the two are closely coordinated and integrated.

Embodiment 22:

FIG22 is a schematic diagram of the architecture of a monitoring system. As shown in FIG22, a plurality of high-voltage electrical equipment provided with sulfur hexafluoride gas chambers and a plurality of transmitters are connected to the background monitoring terminal in turn through a hub and an IEC61850 protocol converter. Among them, each transmitter is respectively arranged on the high-voltage electrical equipment of the corresponding sulfur hexafluoride gas chamber. In this embodiment, the background monitoring terminal PC communicates with a plurality of hubs HUB (HUB1, HUB2, ... HUBm) through a hub HUB0. Each hub HUB is connected to a group of transmitters, such as hub HUB1 connected to transmitters Z11, Z12, ... Z1n, hub HUB2 connected to transmitters Z21, Z22, ... Z2n, ..., hub HUBm connected to transmitters Zm1, Zm2, ... Zmn, wherein m and n are both natural numbers.

The backend monitoring terminal includes: 1) Backend software platform: based on Windows, Linux and others, or VxWorks, Android, Unix, UCos, FreeRTOS, RTX, embOS, MacOS. 2) Backend software key business modules: such as permission management, device management, data storage and query, as well as user management, alarm management, real-time data, historical data, real-time curves, historical curves, configuration management, data collection, data analysis, recording conditions, exception handling, etc. 3) Interface configuration: such as Form interface, Web interface, configuration interface, etc.

Embodiment 23:

FIG23 is a schematic diagram of the architecture of a monitoring system. Compared with Example 22, this embodiment adds a network switch Gateway, an integrated application server Server, and a protocol converter/online monitoring intelligent unit ProC. In this embodiment, the backend monitoring terminal PC is connected to two integrated application servers Server1 and Server2 through the network switch Gateway, and the two integrated application servers Server1 and Server2 communicate with multiple protocol converters/online monitoring intelligent units ProC (ProC1, ProC2, ... ProCn) through the station control layer A network and B network, and the protocol converter/online monitoring intelligent unit ProC communicates with multiple hubs HUB (HUB1, HUB2, ... HUBm) through the R5485 network. Each hub HUB is connected to a group of transmitters, such as hub HUB1 connected to transmitters Z11, Z12, ... Z1n, hub HUB2 connected to transmitters Z21, Z22, ... Z2n, ..., hub HUBm connected to transmitters Zm1, Zm2, ... Zmn, where m and n are both natural numbers.

Embodiment 24:

Figure 24 is a schematic diagram of the architecture of a monitoring system. This embodiment is a schematic diagram of the architecture of a wireless transmission method, and the dotted box in the figure indicates that the wireless module Wn and the transmitter Zn can be made into one or separate parts, and the specific solution can be flexible.

Multiple integrated application servers Server1, Server2, ... Server n communicate wirelessly with each transmitter via the cloud Cluod, a wireless gateway, and a wireless module of each transmitter, wherein n is a natural number.

In addition to online calibration of gas density relays, the system can also monitor the temperature, pressure, density, micro-water and other physical quantities of SF6 gas inside circuit breakers, GIS and other electrical equipment and their changing trends in real time, and has a communication interface to upload data to the background monitoring terminal, realizing the online monitoring function of SF6 gas density, micro-water and other physical quantities of circuit breakers, GIS and other electrical equipment, and can flexibly set alarm limits, query historical data on the spot, accurately analyze and judge the leakage trend and leakage rate of equipment, and discover abnormal conditions of equipment in advance, so as to ensure the safe operation of the entire system of electrical equipment and substations, and truly realize the online monitoring of electrical equipment in substations, especially unmanned stations. Configuration principle: The system should be built with a bus-type hierarchical distributed structure to meet the three-layer architecture requirements of the intelligent substation: process layer (sensor layer, i.e., transmitter used for online calibration of density relays), interval layer (data transmission, acquisition processing layer), station control layer (monitoring host, database server, etc.), and the overall system adopts the IEC61850 standard power communication protocol. The back-end monitoring terminal is responsible for the collection, comprehensive analysis, fault diagnosis, storage and standardized data forwarding of monitoring data, and has functions such as real-time data display, trend analysis, historical data query, and real-time alarm. Through this system, it is possible to monitor the gas density and micro-water of high-voltage electrical equipment online without going to the site, and to calibrate and test the gas density relay online. It can provide a solid basis for the status maintenance of SF6 electrical equipment through expert analysis software, big data analysis, and trend analysis, meet the needs of power grid automation and equipment status maintenance, and play an important role in improving the safe operation and operation management level of the power grid system, carrying out expected diagnosis and trend analysis, and reducing unplanned power outages and maintenance.

The calibration accuracy of the transmitter calibration gas density relay can be related to the power industry or national standards. At different temperatures, its calibration requirements can be based on national standards or industry standards. For example, according to the temperature compensation performance provisions of Article 4.8 of DL/T 259 "Calibration Procedure for Sulfur Hexafluoride Gas Density Relay", the accuracy requirements corresponding to each temperature value, that is, the error judgment requirements are different, which can be based on standards or other regulations. Comparison and judgment can be made for the same period (or season) of different years. For example, the calibration results in May 2021 can be directly compared with the calibration results in May 2019 and May 2020, and trend analysis can be performed for judgment. The calibration can be carried out when the calibration is needed, and a mobile design can also be carried out, that is, it can work in substation A for a period of time, and after completing the task, it can move to substation B to work for a period of time, and after completing the task, it can move to substation C to work.

The calibration accuracy of the transmitter used for online calibration of density relays in the present application can reach 0.25 at 20 degrees, and reach 0.625 at high or low temperatures. The calibration accuracy meets the requirements and meets the requirements or relevant specifications from an economic and metrological point of view.

The specific embodiments of the present invention are described in detail above, but they are only 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 made to the present invention are also within the scope of the present invention. Therefore, the equalization changes and modifications made without departing from the spirit and scope of the present invention should be included in the scope of the present invention.

Claims (66)

1. A transmitter for an on-line check density relay, comprising: the intelligent control system comprises a shell, and a pressure sensor, a temperature sensor, a communication module, an intelligent control unit and an equipment connecting joint which are arranged in the shell, wherein the transmitter is communicated with electric equipment and a gas density relay through the equipment connecting joint; the transmitter also comprises a valve, a pressure regulating mechanism and an on-line check joint signal sampling unit; wherein,

One end of the valve is communicated with the equipment connecting joint, and the other end of the valve is communicated with the gas circuit of the gas density relay and the pressure sensor;

The pressure regulating mechanism is communicated with the gas path of the gas density relay and the gas path of the pressure sensor, and is configured to regulate the pressure rise and fall of the gas path of the gas density relay so as to enable the gas density relay to generate contact action;

the pressure sensor is communicated with the gas density relay on a gas path;

the on-line checking contact signal sampling unit is respectively connected with the signal generator of the gas density relay and the intelligent control unit, and is used for sampling contact signals generated when the gas density relay is in contact action and transmitting the contact signals to the intelligent control unit; the on-line check contact signal sampling unit comprises a first connecting circuit and a second connecting circuit; the first connecting circuit is connected with the contact point of the gas density relay and the contact point signal control loop, and the second connecting circuit is connected with the contact point of the gas density relay and the intelligent control unit; in a non-verification state, the contact is a normally open type density relay, the second connecting circuit is opened or isolated, and the first connecting circuit is closed; in a verification state, the first connecting circuit is disconnected, the second connecting circuit is communicated, and the contact point of the gas density relay is connected with the intelligent control unit; or in a non-checking state, the contact is a normally-closed density relay, the second connecting circuit is opened or isolated, and the first connecting circuit is closed; in the verification state, the contact signal control loop is closed, the connection between the contact of the gas density relay and the contact signal control loop is disconnected, and the second connection circuit is communicated to connect the contact of the gas density relay with the intelligent control unit;

The intelligent control unit is also respectively connected with the valve, the pressure regulating mechanism, the pressure sensor, the temperature sensor and the communication module, and is used for converting data acquired by the pressure sensor and the temperature sensor into standard signals, controlling the valve to be closed or opened, completing the control of the pressure regulating mechanism, receiving a pressure value and a temperature value and/or a gas density value when a contact point of the gas density relay acts, and remotely transmitting the pressure value and the temperature value and/or the gas density value to a corresponding detection system or target equipment through the communication module;

wherein the contact signal includes an alarm and/or a latch.

2. The transmitter for an on-line check density relay of claim 1, wherein: the signal generator comprises a micro switch or a magnetic-assisted electric contact, and the gas density relay outputs a contact signal through the signal generator.

3. The transmitter for an on-line check density relay of claim 1, wherein: the intelligent control unit converts the data acquired by the pressure sensor and the temperature sensor into a gas density value, namely a pressure value corresponding to 20 ℃; or converted into a digital signal of the gas density value to complete the on-line monitoring of the gas density.

4. The transmitter for an on-line check density relay of claim 3, wherein: the intelligent control unit calculates the gas density value by adopting a mean value method, wherein the mean value method is as follows: setting acquisition frequency in a set time interval, and carrying out average value calculation processing on all N acquired gas density values at different time points to obtain gas density values; or alternatively

In a set time interval, setting a temperature interval step length, and carrying out average value calculation on density values corresponding to N different temperature values acquired in all temperature ranges to obtain a gas density value; or alternatively

In a set time interval, setting a pressure interval step length, and carrying out average value calculation on density values corresponding to N different pressure values acquired in all pressure variation ranges to obtain a gas density value;

Wherein N is a positive integer greater than or equal to 1.

5. The transmitter for an on-line check density relay of claim 1, wherein: the intelligent control unit converts the data acquired by the pressure sensor and the temperature sensor into current signals with corresponding density values.

6. The transmitter for an on-line check density relay of claim 5, wherein: the current signal is a direct current signal.

7. The transmitter for an on-line check density relay of claim 6, wherein: the direct current signal is 0-10 mA or 4-20 mA.

8. The transmitter for an on-line check density relay of claim 1, wherein: the intelligent control unit converts the data acquired by the pressure sensor and the temperature sensor into voltage signals with corresponding density values.

9. The transmitter for an on-line check density relay of claim 8, wherein: the voltage signal is a direct current voltage signal.

10. The transmitter for an on-line check density relay of claim 9, wherein: the direct-current voltage signal is 1-5V.

11. The transmitter for an on-line check density relay of claim 1, wherein: the intelligent control unit is based on an embedded algorithm and a control program of the embedded system of the microprocessor and automatically controls the whole verification process, and comprises all peripherals, logic and input and output.

12. The transmitter for an on-line check density relay of claim 1, wherein: the intelligent control unit acquires the pressure value and the temperature value acquired by the pressure sensor and the temperature sensor when the gas density relay is in contact action, and converts the pressure value and the temperature value into the pressure value corresponding to 20 ℃ according to the gas pressure-temperature characteristic, namely the gas density value, so as to finish the online verification of the gas density relay.

13. The transmitter for an on-line check density relay of claim 1, wherein: the transmitter automatically realizes the testing of the absolute pressure type gas density relay and/or the relative pressure type gas density relay.

14. The transmitter for an on-line check density relay of claim 1, wherein: the intelligent control unit is provided with an electrical interface, and the electrical interface is used for completing test data storage, and/or test data export, and/or test data printing, and/or data communication with an upper computer, and/or inputting analog quantity or digital quantity information.

15. The transmitter for an on-line check density relay of claim 14, wherein: the electrical interface is provided with an electrical interface protection circuit that prevents the interface from being damaged by a user misconnection and/or prevents electromagnetic interference.

16. The transmitter for an on-line check density relay of claim 1, wherein: the intelligent control unit is also provided with a clock, and the clock is used for periodically setting check time, recording test time or recording event time.

17. The transmitter for an on-line check density relay of claim 1, wherein: the transmitter monitors the gas density value of the electrical equipment on line, and if the gas density value is abnormal, the transmitter starts on-line verification of the gas density relay.

18. The transmitter for an on-line check density relay of claim 1, wherein: after the transmitter finishes the verification of the gas density relay, the intelligent control unit automatically generates a verification report of the gas density relay, and if the verification report is abnormal, the intelligent control unit automatically gives an alarm, and/or uploads the alarm to a far end and/or sends the alarm to a designated receiver.

19. The transmitter for an on-line check density relay of claim 1, wherein: after the transmitter finishes the verification of the gas density relay, if the gas density relay is abnormal, the intelligent control unit uploads an alarm contact signal of the gas density relay to a far end and/or sends the alarm contact signal to a designated receiver through a communication module.

20. The transmitter for an on-line check density relay of claim 1, wherein: the valve is an electric valve and/or an electromagnetic valve, or a piezoelectric valve, or a temperature-controlled valve, or a novel valve which is made of intelligent memory materials and is opened or closed by electric heating.

21. The transmitter for an on-line check density relay of claim 1, wherein: the valve is closed or opened in a hose bending or flattening mode.

22. The transmitter for an on-line check density relay of claim 1, wherein: the valve is sealed in a cavity; or alternatively

The valve and the pressure regulating mechanism are sealed within a cavity.

23. The transmitter for an on-line check density relay of claim 1, wherein: the valve is closed, the pressure regulating mechanism is boosted, the load is increased, or the pressure regulating mechanism is depressurized, the load is reduced, and the change speed of the load is not more than 10 per mill of the measuring range of the gas density relay per second.

24. The transmitter for an on-line check density relay of claim 1, wherein: pressure sensors are respectively arranged on two sides of the gas path of the valve; or pressure or density detectors are respectively arranged on two sides of the gas path of the valve.

25. The transmitter for an on-line check density relay of claim 1, wherein: the front end of the valve is provided with a density relay or a density switch, and a signal of a safety check set point is output and is connected with the intelligent control unit.

26. The transmitter for an on-line check density relay of claim 1, wherein: the temperature sensor is arranged on or in the housing of the gas density relay or on or in the housing of the transmitter.

27. The transmitter for an on-line check density relay of claim 1, wherein: at least one temperature sensor is arranged near or on or integrated in a temperature compensation element of the gas density relay, which temperature compensation element adopts a temperature compensation sheet or a gas enclosed in a shell.

28. The transmitter for an on-line check density relay of claim 27, wherein: at least one temperature sensor is disposed at an end of the pressure detector of the gas density relay adjacent to the temperature compensation element.

29. The transmitter for an on-line check density relay of claim 1, wherein: the pressure sensor and the temperature sensor are of an integrated structure.

30. The transmitter for an on-line check density relay of claim 29, wherein: the integrated structure formed by the pressure sensor and the temperature sensor has a remote transmission function, and remotely transmits the monitored pressure value and temperature value, and/or the gas density value, and/or the joint signal of the remote transmission gas density relay.

31. The transmitter for an on-line check density relay of claim 1, wherein: the transmitter comprises at least two pressure sensors, pressure values acquired by the pressure sensors are compared, and mutual verification among the pressure sensors is completed.

32. The transmitter for an on-line check density relay of claim 1, wherein: the transmitter comprises at least two temperature sensors, temperature values acquired by the temperature sensors are compared, and mutual verification among the temperature sensors is completed.

33. The transmitter for an on-line check density relay of claim 1, wherein: the transmitter includes at least one pressure sensor and at least one temperature sensor; the pressure values acquired by the pressure sensors and the temperature values acquired by the temperature sensors are arranged and combined randomly, each combination is converted into a plurality of corresponding pressure values at 20 ℃ according to the gas pressure-temperature characteristics, namely gas density values, and the gas density values are compared to finish the mutual verification of the pressure sensors and the temperature sensors; or the pressure value collected by each pressure sensor and the temperature value collected by each temperature sensor are traversed through all the arrangement combinations, each combination is converted into a plurality of corresponding pressure values at 20 ℃ according to the gas pressure-temperature characteristics, namely gas density values, and each gas density value is compared to finish the mutual verification of each pressure sensor and each temperature sensor; or comparing a plurality of gas density values obtained by each pressure sensor and each temperature sensor with comparison density value output signals output by the gas density relay to finish the mutual verification of the gas density relay, each pressure sensor and each temperature sensor; or comparing the gas density values, the pressure values and the temperature values obtained by the pressure sensors and the temperature sensors to finish the mutual verification of the gas density relay, the pressure sensors and the temperature sensors.

34. The transmitter for an on-line check density relay of claim 1, wherein: the transmitter is provided with a comparison density value output signal which is connected with the intelligent control unit; or the transmitter is provided with a comparison pressure value output signal which is connected with the intelligent control unit.

35. The transmitter for an on-line check density relay of claim 1, wherein: the pressure regulating mechanism is a closed air chamber, a heating element and/or a refrigerating element is arranged outside or inside the closed air chamber, the temperature of the air in the closed air chamber is changed due to the heating of the heating element and/or the refrigerating of the refrigerating element, and then the pressure rise and fall of the air density relay are completed.

36. The transmitter for an on-line check density relay of claim 35, wherein: the heating element and/or the cooling element is a semiconductor.

37. The transmitter for an on-line check density relay of claim 35, wherein: the pressure regulating mechanism further comprises a heat preservation piece, and the heat preservation piece is arranged outside the closed air chamber.

38. The transmitter for an on-line check density relay of claim 1, wherein: the pressure regulating mechanism is a cavity with one end open, and the other end of the cavity is communicated with a gas path of the gas density relay; the piston is arranged in the cavity, one end of the piston is connected with an adjusting rod, the outer end of the adjusting rod is connected with 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, and the driving component drives the adjusting rod to drive the piston to move in the cavity; or alternatively

The pressure regulating mechanism is a closed air chamber, a piston is arranged in the closed air chamber, the piston is in sealing contact with the inner wall of the closed air chamber, a driving component is arranged outside the closed air chamber, and the driving component pushes the piston to move in the closed air chamber through electromagnetic force; or alternatively

The pressure regulating mechanism is an air bag with one end connected with the driving component, and the air bag is subjected to volume change under the driving of the driving component; or alternatively

The pressure regulating mechanism is a corrugated pipe, one end of the corrugated pipe is communicated with the gas density relay, and the other end of the corrugated pipe stretches under the drive of the driving part; or alternatively

The pressure regulating mechanism is a deflation valve, and the deflation valve is an electromagnetic valve or an electric valve or other deflation valves realized by an electric or gas mode; or alternatively

The pressure regulating mechanism is a compressor; or alternatively

The pressure regulating mechanism is a pump, and the pump comprises a pressure-making pump, a booster pump, an electric air pump or an electromagnetic air pump;

Wherein the driving component comprises one of magnetic force, a motor, a Carnot circulation mechanism and a pneumatic element.

39. The transmitter for an on-line check density relay of claim 1, wherein: the pressure regulating mechanism is sealed in a cavity.

40. The transmitter for an on-line check density relay of claim 1, wherein: the on-line checking contact signal sampling unit is provided with at least two independent sampling contacts, can automatically complete checking on at least two contacts of the gas density relay at the same time, and is used for continuous measurement without replacing the contacts or reselecting the contacts; wherein,

The contacts comprise one of an alarm contact, a locking contact, an alarm contact, a locking 1 contact, a locking 2 contact, an alarm contact, a locking contact and an overpressure contact.

41. The transmitter for an on-line check density relay of claim 1, wherein: and the on-line checking contact signal sampling unit applies a voltage not lower than 24V to the contact action value or the switching value of the gas density relay, namely, when checking, the voltage not lower than 24V is applied between the corresponding terminals of the contact.

42. The transmitter for an on-line check density relay of claim 1, wherein: the on-line checking joint signal sampling unit and the intelligent control unit are arranged together.

43. A transmitter for an on-line check density relay according to claim 42, wherein: the on-line checking joint signal sampling unit and the intelligent control unit are sealed in a cavity.

44. The transmitter for an on-line check density relay of claim 1, wherein: the first connecting circuit comprises a first relay, the second connecting circuit comprises a second relay, the first relay is provided with at least one normally-closed contact, the second relay is provided with at least one normally-open contact, and the normally-closed contact and the normally-open contact keep opposite switch states; the normally-closed contact is connected in series in the contact signal control loop, and the normally-open contact is connected to the contact of the gas density relay;

in a non-verification state, the normally-closed contact is closed, the normally-open contact is opened, and the gas density relay monitors the output state of the contact in real time; in the verification state, the normally-closed contact is opened, the normally-open contact is closed, and the contact of the gas density relay is connected with the intelligent control unit through the normally-open contact.

45. The transmitter for an on-line check density relay of claim 44, wherein: the first relay and the second relay are two independent relays or the same relay.

46. The transmitter for an on-line check density relay of claim 1, wherein: the on-line checking contact signal sampling unit is electrically isolated from the contact of the gas density relay by photoelectricity.

47. The transmitter for an on-line check density relay of claim 1, wherein: the communication mode of the communication module is a wired communication mode or a wireless communication mode.

48. The transmitter for an on-line check density relay of claim 1, wherein: the transmitter further includes a multi-way joint, and the gas density relay, valve and pressure regulating mechanism are disposed on the multi-way joint.

49. A transmitter for an on-line check density relay according to claim 48, wherein: the valve is embedded on the multi-way joint.

50. A transmitter for an on-line check density relay according to claim 48, wherein: the transmitter further comprises a self-sealing valve, and the self-sealing valve is installed on the multi-way joint.

51. The transmitter for an on-line check density relay of claim 1, wherein: the transmitter further comprises a micro water sensor, wherein the micro water sensor is connected with the intelligent control unit and is used for monitoring the gas micro water value on line.

52. The transmitter for an on-line check density relay of claim 51, wherein: the transmitter also comprises a gas circulation mechanism, the gas circulation mechanism is connected with the intelligent control unit, the gas circulation mechanism comprises a capillary tube, a sealed cavity and a heating element, the gas circulation mechanism is heated by the heating element to realize gas flow, and the gas micro-water value is monitored on line.

53. The transmitter for an on-line check density relay of claim 1, wherein: the transmitter further comprises a decomposition product sensor for on-line monitoring of gas decomposition products, and the decomposition product sensor is connected with the intelligent control unit.

54. The transmitter for an on-line check density relay of claim 1, wherein: the transmitter also includes a gas density relay including a digital or liquid crystal display device having an indication display.

55. The transmitter for an on-line check density relay of claim 1, wherein: the transmitter also comprises a data display interface for man-machine interaction, and can refresh the current data value in real time; and/or support data entry.

56. The transmitter for an on-line check density relay of claim 1, wherein: the valve and the pressure regulating mechanism are connected together through a connecting pipe.

57. The transmitter for an on-line check density relay of claim 1, wherein: the pressure sensor, the temperature sensor, the on-line checking joint signal sampling unit and the intelligent control unit are arranged in or on the shell of the gas density relay.

58. The transmitter for an on-line check density relay of claim 1, wherein: the transmitter also comprises a power supply for supplying power to each electric equipment, wherein the power supply comprises a power supply circuit, or a battery or a power supply obtained by taking power from a transformer.

59. The transmitter for an on-line check density relay of claim 1, wherein: the transmitter periodically sets the time for checking the gas density relay on line.

60. The transmitter for an on-line check density relay of claim 1, wherein: when the gas density value or the pressure value is lower than the set value, the transmitter automatically does not check and sends out a notification signal.

61. The transmitter for an on-line check density relay of claim 1, wherein: the transmitter is also provided with a temperature protection device for the electronic components, and the temperature protection device is used for ensuring that the electronic components reliably work at low temperature or high temperature environment temperature; the temperature protection device comprises a heater and/or a radiator, wherein the heater is started when the temperature is lower than a set value, and the radiator is started when the temperature is higher than the set value.

62. The transmitter for an on-line check density relay of claim 1, wherein: the transmitter also includes an analysis system for monitoring the gas density value and for detecting, analyzing and determining the electrical performance of the gas density relay and the monitoring element.

63. The transmitter for an on-line check density relay of claim 1, wherein: the transmitter further comprises a camera for monitoring.

64. A monitoring system, characterized by: the monitoring system is constituted by a transmitter for an on-line check density relay of any one of claims 1 to 63; or the monitoring system includes a transmitter for an on-line check density relay of any one of claims 1 to 63.

65. The method for implementing a transmitter for an on-line check density relay of claim 1, wherein: comprising the following steps:

During normal operation, a transmitter for an on-line check density relay monitors the gas density in the electrical equipment, and simultaneously the transmitter remotely transmits the monitored pressure value and temperature value and/or the gas density value in the electrical equipment through a pressure sensor, a temperature sensor and an intelligent control unit;

the transmitter is according to the check time and/or check command that set for, and the gas density value condition, under the condition that allows checking gas density relay:

The intelligent control unit is used for adjusting the pressure regulating mechanism to a verified initial state;

closing the valve by an intelligent control unit;

The on-line checking contact signal sampling unit is adjusted to a checking state through the intelligent control unit, and in the checking state, the on-line checking contact signal sampling unit cuts off a contact signal control loop of the gas density relay to connect a contact of the gas density relay to the intelligent control unit;

The intelligent control unit drives the pressure regulating mechanism to enable the gas pressure to slowly drop, so that the gas density relay generates contact action, the contact action is transmitted to the intelligent control unit through the on-line checking contact signal sampling unit, the intelligent control unit directly obtains the gas density value according to the pressure value and the temperature value during the contact action, the contact action value of the gas density relay is detected, and the checking work of the contact action value of the gas density relay is completed;

After all the verification works are completed, the intelligent control unit opens the valve, and adjusts the on-line verification contact signal sampling unit to a working state, and the contact signal control loop of the gas density relay resumes to operate in a normal working state.

66. The method of implementing a transmitter for an on-line check density relay of claim 65, further comprising:

After the transmitter finishes the verification work of the contact action value of the gas density relay, and before the valve is opened, the intelligent control unit drives the pressure regulating mechanism through the intelligent control unit to enable the gas pressure to slowly rise, so that the gas density relay is subjected to contact reset, the contact reset is transmitted to the intelligent control unit through the on-line verification contact signal sampling unit, the intelligent control unit directly obtains the gas density value according to the pressure value and the temperature value during the contact reset, the contact return value of the gas density relay is detected, and the verification work of the contact return value of the gas density relay is finished.