SF6 detection system and sensor calibration method thereof

Abstract

The invention relates to the technical field of electric power detection, in particular to an SF6 detection system and a sensor calibration method thereof. Comprising a host, a PoE switch and a plurality of sensors. The PoE switch is provided with a plurality of network ports, and the host and the plurality of sensors are respectively connected to different network ports of the PoE switch so as to realize wired communication; a first wireless communication module is arranged in the host and is used for wirelessly communicating with the server and the plurality of sensors; a second wireless communication module is arranged in each sensor and is used for wirelessly communicating with the server and the host; according to the scheme, power supply and data transmission between the host and the multiple sensor devices are achieved, the number of system cables and interfaces is effectively reduced, unification of the interfaces and unification of communication protocols in the system are achieved, and the system compatibility is higher; the host is in wired and wireless connection with the plurality of sensors at the same time, the server can access the sensors through the host and can also directly access the sensors, uniform interfaces of a power grid are achieved, and data are safer.

Description

Technical Field

[0001] The present invention relates to the technical field of electric power detection, and in particular to an SF6 detection system and a sensor calibration method thereof. Background Art

[0002] SF6 is a colorless, odorless, non-toxic and non-flammable gas. It is widely used in gas insulated switchgear (GIS) due to its good electrical insulation and arc extinguishing properties. GIS has many advantages over conventional electrical equipment, but from the perspective of long-term operation, there is a risk of SF6 gas leakage due to factors such as the manufacturing process of power equipment, installation environment, and equipment aging. SF6 gas leakage may cause serious safety problems and environmental impacts. SF6 gas sensors need to be installed in the scene to avoid accidents.

[0003] Traditional SF6 gas sensors generally use analog output. The analog signal will be interfered and attenuated after long-distance transmission, resulting in a large difference between the detection value and the measurement value. At present, some digital SF6 gas sensors have also appeared on the market. Although they use digital transmission, the number of host connections is limited, generally not more than 256, and there is no unified information security and interface, and they cannot be directly returned to the server.

[0004] Therefore, it is crucial for technical personnel in this field to design an SF6 detection system and a sensor calibration method thereof that has higher interface protocol and functional compatibility and can mount multiple smart sensors. Summary of the invention

[0005] The technical problem to be solved by the embodiments of the present invention is to provide an SF6 detection system and a sensor calibration method thereof with higher interface protocol and functional compatibility and capable of mounting multiple intelligent sensors, so as to solve the problems in the prior art of multiple equipment connection cables, ununified protocols, and inability to form unified data management.

[0006] The present invention discloses an SF6 detection system, which comprises: a host, a PoE switch and a plurality of sensors; the PoE switch comprises a plurality of network ports, the host and the plurality of sensors are respectively connected to different network ports of the PoE switch for wired communication between the host and the plurality of sensors; a first wireless communication module is arranged in the host for wireless communication with a server and the plurality of sensors; a second wireless communication module is arranged in each of the sensors for wireless communication with the server and the host.

[0007] Optionally, a main control module and a display module are further provided in the host, the main control module is connected to the first wireless communication module, and the display module is connected to the main control module.

[0008] Optionally, the main control module is equipped with the Dianhong IoT operating system.

[0009] Optionally, the PoE switch adopts IPV6 protocol.

[0010] Optionally, the plurality of sensors include a SF6 sensor, an oxygen sensor, a temperature sensor and a humidity sensor.

[0011] Optionally, the oxygen sensor includes a voltage follower circuit, a sensor module, a conversion circuit and an amplifier circuit, the output end of the voltage follower circuit is connected to the input end of the sensor module, the input end of the conversion circuit is connected to the output end of the sensor module, so as to convert the current signal into a voltage signal, the output end of the conversion circuit is connected to the input end of the amplifier circuit, and the output end of the amplifier circuit is connected to the host for ADC sampling.

[0012] In order to solve the problems existing in the prior art, the present invention further provides a sensor calibration method for calibrating the oxygen sensor as described above, and the method comprises the following steps:

[0013] Obtain the relationship curve between voltage and oxygen concentration value under standard conditions;

[0014] According to the relationship curve and the current acquisition voltage, the current original value of oxygen concentration is obtained;

[0015] Obtain the average value of the original value of oxygen concentration within the preset time, and calibrate it with the normal oxygen concentration value in the atmosphere to obtain the calibration coefficient;

[0016] The actual value of the calibrated oxygen concentration is calculated based on the calibration coefficient and the current original value of the oxygen concentration.

[0017] Optionally, the calculation formula of the original value of oxygen concentration is: C=(V-5) / 2.6, wherein C is the current original value of oxygen concentration, and V is the current acquisition voltage.

[0018] Optionally, the calibration coefficient is obtained by the formula: K=20.9 / C1, wherein C1 is the average value of the original value of the oxygen concentration within a preset time, and K is the calibration coefficient.

[0019] Optionally, the calculation formula for the actual value of oxygen concentration is: C2=K*C, wherein C2 is the actual value of oxygen concentration and K is the calibration coefficient.

[0020] Compared with the prior art, the beneficial effects of the SF6 detection system provided by the embodiment of the present invention are: by designing an SF6 detection system, including a host, a PoE switch and multiple sensors; the PoE switch includes multiple network ports, and the host and multiple sensors are respectively connected to different network ports of the PoE switch for wired communication between the host and the multiple sensors; a first wireless communication module is arranged in the host for wireless communication with the server and the multiple sensors; a second wireless communication module is arranged in each sensor for wireless communication with the server and the host; by setting the PoE switch, power supply and data wired transmission between the host and the multiple sensor devices are realized, and power supply and communication are integrated, which not only effectively reduces the number of cables and interfaces in the system, but also realizes the unification of interfaces and communication protocols in the system, making the system more compatible; by setting the first wireless communication module in the host and setting the second wireless communication module in the multiple sensors, not only the host and the multiple sensors have wired and wireless connections at the same time, but also the server can not only access the sensor through the host, but also directly access the sensor, realizing a unified interface of the power grid, and the data is more secure. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments, in which:

[0022] Figure 1 The structural framework of the SF6 detection system provided by the embodiment of the present invention Figure 1 ;

[0023] Figure 2 The structural framework of the SF6 detection system provided by the embodiment of the present invention Figure 2 ;

[0024] Figure 3 The circuit of the oxygen sensor provided by the embodiment of the present invention is Figure 1 ;

[0025] Figure 4 The circuit of the oxygen sensor provided by the embodiment of the present invention is Figure 2 ;

[0026] Figure 5 is a flow chart of a sensor calibration method provided by an embodiment of the present invention;

[0027] Figure 6 It is the relationship curve between voltage and oxygen concentration value under the standard state in the present invention. DETAILED DESCRIPTION

[0028] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. Now, in conjunction with the accompanying drawings, the preferred embodiments of the present invention are described in detail.

[0029] like Figures 1 to 4 As shown, the present invention provides a specific embodiment of a SF6 detection system.

[0030] A SF6 detection system, reference Figure 1 The SF6 detection system includes a host 100, a PoE switch 200 and multiple sensors 300; the PoE switch 200 includes multiple network ports 210, and the host 100 and the multiple sensors 300 are respectively connected to different network ports 210 of the PoE switch 200 for wired communication between the host 100 and the multiple sensors 300; a first wireless communication module 110 is arranged in the host 100 for wireless communication with a server and multiple sensors 300; each sensor 300 is arranged in a second wireless communication module 310 for wireless communication with a server and the host 100.

[0031] Specifically, refer to Figure 1 The PoE switch 200 is a network switch that can provide power supply to connected devices via an Ethernet cable, allowing power to be transmitted to PoE-enabled devices via a network cable without an additional power line.

[0032] refer to Figure 2 The PoE switch 200 is provided with multiple network ports 210, and the multiple network ports 210 all adopt a unified communication protocol, support the connection method of traditional DC24V+RS485 power supply communication, and support a flexible combination of multiple SF6 sensors 301, oxygen sensors 302, humidity sensors 303 and temperature sensors 304. After the host 100 is connected to the network port 210 of the PoE switch 200, a wired (Ethernet) connection can be achieved with multiple sensors 300 through the PoE switch 200.

[0033] By setting up a PoE switch 200 in the system, the host 100 and multiple sensors 300 can be connected to the PoE switch 200. The host 100 can communicate with multiple connected sensors 300 through the PoE switch 200 to obtain different detection data. Communication and power supply between multiple devices can be achieved through the PoE switch 200, which not only effectively reduces the number of cables and interfaces in the system, but also realizes the unification of interfaces and communication protocols in the system, making the system more compatible and realizing plug-and-play of equipment.

[0034] Further, refer to Figure 1A first wireless communication module 110 is provided in the host 100, and a second wireless communication module 310 is provided in each connected sensor 300. The first wireless communication module 110 can be connected to the second wireless communication module 310 to realize a wireless connection between the host 100 and the multiple sensors 300, so that there are two communication modes between the host 100 and the multiple sensors 300, namely wireless communication and wired (Ethernet) communication, and the two communication modes back up each other.

[0035] Among them, the host 100 can also be connected to the cloud server through the first wireless communication module 110 to transmit the acquired detection data of the sensor 300 to the cloud server; multiple sensors 300 can also be directly connected to the cloud server through their second wireless communication modules 310 to transmit the detected detection data directly to the cloud server; so that the platform supports multi-channel access, and the sensor 300 can be accessed directly or through the on-site host 100.

[0036] Furthermore, both the first wireless communication module 110 and the second wireless communication module 310 can adopt StarLink wireless communication technology. StarLink wireless communication technology is also called StarLink protocol, which is a wireless communication protocol based on extremely low latency and high reliability. It is designed to meet the extremely high requirements of wireless communications in scenarios such as the Internet of Things, autonomous driving, and industrial automation. By adopting advanced coding, modulation, and multiple access technologies, it can achieve efficient and stable data transmission in complex wireless environments.

[0037] Specifically, Starflash wireless communication technology adopts a short frame structure and a fast retransmission mechanism, which greatly reduces the delay of data transmission and can effectively improve the overall performance of the system; in addition, Starflash wireless communication technology adopts forward error correction, interference suppression and other technical means, which makes it have strong anti-interference ability, and can ensure reliable data transmission even in the case of poor signal quality; Starflash wireless communication technology also adopts energy-saving transmission mode and power control strategy, while ensuring communication performance, it effectively reduces the energy consumption of equipment and extends battery life; more importantly, Starflash wireless communication technology supports a variety of physical layer and data link layer parameter configurations, which can be flexibly adjusted according to the needs of different scenarios. At the same time, its modular design makes the protocol easier to expand and maintain.

[0038] Traditional SF6 gas sensors generally use analog output. Analog signals will be interfered and attenuated after long-distance transmission, resulting in a large difference between the detection value and the measurement value. Although the digital SF6 gas sensors currently on the market use digital transmission, the number of host connections is limited, generally not exceeding 256, and there is no unified information security and interface, and they cannot be directly returned to the server.

[0039] In the present invention, a SF6 detection system is designed, including a host 100, a PoE switch 200 and a plurality of sensors 300; the PoE switch 200 includes a plurality of network ports 210, the host 100 and the plurality of sensors 300 are respectively connected to different network ports 210 of the PoE switch 200, so as to be used for wired communication between the host 100 and the plurality of sensors 300; a first wireless communication module 110 is arranged in the host 100, so as to be used for wireless communication with a server and the plurality of sensors 300; a second wireless communication module 310 is arranged in each sensor 300, so as to be used for wireless communication with the server and the host 100; and the PoE switch 200 is arranged to realize the wireless communication between the host 100 and the plurality of sensors 300. The power supply and wired data transmission between the host 100 and multiple sensor 300 devices realize the integration of power supply and communication, which not only effectively reduces the number of cables and interfaces in the system, but also realizes the unification of interfaces and communication protocols in the system, making the system more compatible; by setting a first wireless communication module 110 in the host 100 and a second wireless communication module 310 in multiple sensors 300, not only is there a wired and wireless connection between the host 100 and the multiple sensors 300, but also the server can not only access the sensor 300 through the host 100, but also directly access the sensor 300, realizing a unified interface of the power grid and making the data more secure.

[0040] In one embodiment, reference Figure 2 A main control module 120 and a display module 130 are also provided in the host 100 . The main control module 120 is connected to the first wireless communication module 110 , and the display module 130 is connected to the main control module 120 .

[0041] Specifically, refer to Figure 2 The main control module 120 is equipped with the Dianhong IoT operating system, namely the Southern Power Grid's "Dianhong OS" operating system, which has the characteristics of the Internet of Everything and can realize functions similar to the interconnection of mobile phones, tablet computers, smart terminals and other devices. Through the interconnection of the Hongmeng system, unified management and interactive collaboration are realized, making information transmission and processing clearer and more efficient. In this embodiment, by being equipped with the Dianhong IoT operating system, the system's data security, business processing, data processing and protocol unification requirements are met.

[0042] Furthermore, the display module 130 adopts a 3.5-inch IPS true color display screen, which can display the real-time values ​​of SF6, oxygen, temperature and humidity, support on-site operation and maintenance, and facilitate maintenance; at the same time, when the SF6 content exceeds the standard, it can also provide early warning, allowing operation and maintenance personnel to quickly leave the danger zone.

[0043] In one embodiment, the PoE switch 200 uses the IPV6 protocol.

[0044] Specifically, PoE is applied to the power intelligent SF6 sensor 301, and power supply and two-way communication can be achieved through only one network cable. The wiring is simple, and the PoE switch 200 adopts the IPV6 protocol. The IPv6 protocol is an Internet protocol. The IPv6 protocol uses a unique IPV6 communication address. There is no limit on the number of connections. It is plug-and-play and can provide more IP addresses to support the growing number of Internet devices. In addition, the header of the IPv6 communication protocol is concise, which improves the efficiency of the system in processing data packets. The IPv6 communication protocol also introduces the SLAAC mechanism, which allows devices to automatically configure their own IP addresses according to the network prefix, simplifying address management; the IPv6 communication protocol also provides end-to-end encryption and authentication functions, which enhances the security of communications. At the same time, more devices can be connected. The number of connected devices in the same substation is no longer limited by the connection address, further realizing the interconnection of all things.

[0045] In one embodiment, the SF6 sensor 301 is an infrared sensor 300 .

[0046] Specifically, the SF6 sensor 301 can specifically select a high-sensitivity SF6 infrared sensor 300. The SF6 infrared sensor 300 is used to detect and measure the concentration of SF6 gas. The SF6 infrared sensor 300 uses infrared technology to detect the concentration of SF6 gas in the ambient air. When the SF6 gas passes through the SF6 infrared sensor 300, the infrared rays interact with the SF6 molecules in the gas to produce specific absorption characteristics. The SF6 infrared sensor 300 determines the concentration of SF6 gas in the ambient air by measuring the changes in the absorption characteristics.

[0047] In one embodiment, reference Figure 3 and Figure 4 The oxygen sensor 302 includes a voltage follower circuit 3021, a sensor module 3022 and a conversion circuit 3023. The sensor module 3022 is used to detect the current signal. The output end of the voltage follower circuit 3021 is connected to the input end of the sensor module 3022 to provide a reference voltage source. The input end of the conversion circuit 3023 is connected to the output end of the sensor module 3022 to convert the current signal into a voltage signal. The host 100 is connected to the output end of the signal processing module for ADC sampling.

[0048] Specifically, refer to Figure 3 and Figure 4The sensor module 3022 adopts a 0.25% high-precision oxygen sensor 302. The sensor module 3022 includes a positive power terminal HS+ and a negative power terminal HS- for connecting the sensor 300 heating power supply, and also includes a reference source input terminal Sen+ and a signal output terminal Sen-; the voltage follower circuit 3021 includes a first voltage-dividing resistor R1, a second voltage-dividing resistor R2, a third voltage-dividing resistor R3 and a comparator U1. One end of the first voltage-dividing resistor R1 inputs a 3V voltage, and the other end of the first voltage-dividing resistor R1 is respectively connected to one end of the second voltage-dividing resistor R2 and the negative input end of the comparator U1, the other end of the second voltage-dividing resistor R2 is connected to one end of the third voltage-dividing resistor R3, and the other end of the third voltage-dividing resistor R3 is grounded. The output end of the comparator U1 is connected to the reference source input end of the sensor module 3022 to provide a reference signal.

[0049] Further, refer to Figure 3 and Figure 4 The input end of the conversion circuit 3023 is connected to the signal output end of the sensor module 3022 to convert the current signal output by the sensor module 3022 into a voltage signal, thereby facilitating direct ADC sampling by the host 100; the conversion circuit 3023 includes a first amplifier U2, which converts the current signal into a voltage signal, amplifies the converted voltage signal and outputs it.

[0050] In one embodiment, reference Figure 3 and Figure 4 The oxygen sensor 302 further includes an amplifier circuit 3024, an input end of the amplifier circuit 3024 is connected to an output end of the conversion circuit 3023, and an output end of the amplifier circuit 3024 is connected to the host 100 for amplifying the voltage signal.

[0051] Specifically, refer to Figure 3 and Figure 4 The amplifier circuit 3024 includes a second amplifier U3, and the negative input terminal of the second amplifier U3 is connected to the output terminal of the conversion circuit 3023, so as to perform secondary amplification on the voltage signal and impedance matching before ADC. The amplifier circuit 3024 also includes a filtering subcircuit, and the filtering subcircuit includes a filtering resistor R4 and a filtering capacitor C1. One end of the filtering resistor R4 is connected to the second amplifier U3, and the other end of the filtering resistor R4 is respectively connected to the host 100 and one end of the filtering capacitor C1, and the other end of the filtering capacitor C1 is grounded.

[0052] like Figure 5 and Figure 6 As shown, the present invention also provides a specific embodiment of a sensor calibration method.

[0053] A sensor calibration method is used to calibrate the above oxygen sensor 302, referring to Figure 5, the sensor calibration method includes the following steps:

[0054] S1. Obtain the relationship curve between voltage and oxygen concentration value under standard conditions;

[0055] S2. Obtain the current original value of oxygen concentration according to the relationship curve and the current acquisition voltage;

[0056] S3, obtaining an average value of the original value of the oxygen concentration within a preset time, and calibrating it with the normal oxygen concentration value in the atmosphere to obtain a calibration coefficient;

[0057] S4. Calculate the actual value of the calibrated oxygen concentration based on the calibration coefficient and the current original value of the oxygen concentration.

[0058] Specifically, when the oxygen concentration is 0, the voltage is 5mv, and when the oxygen concentration is 100, the voltage is 265mv. Assuming that the relationship between voltage and oxygen concentration is: y = kx + b, and after passing through the two points (0,5) and (100,265), the relationship curve between voltage and oxygen concentration under standard conditions can be obtained (reference Figure 6 KE-50), the current oxygen concentration original value can be calculated through the curvature and the current acquisition voltage.

[0059] Furthermore, the average value of the original value of oxygen concentration within a preset time is collected, and calibrated with the normal oxygen concentration value in the atmosphere to obtain a calibration coefficient. The preset time can be 6 months or longer. The average of the original value of oxygen concentration detected within the preset time can effectively reduce the detection error. By calibrating the original value of oxygen concentration with the normal oxygen concentration value in the atmosphere, the slight difference between the theoretical value and the actual value can be obtained, so as to calibrate the calculated original value of oxygen concentration, and the calibrated original value of oxygen concentration is used as the actual value of oxygen concentration.

[0060] In one embodiment, the calculation formula of the original value of oxygen concentration is: C=(V-5) / 2.6, where C is the current original value of oxygen concentration and V is the current acquisition voltage.

[0061] Specifically, when the oxygen concentration value is 0, the voltage is 5mv, and when the oxygen concentration value is 100, the voltage is 265mv. Assuming that the relationship between voltage and oxygen concentration value is: y=kx+b, and after passing through the two points (0,5) and (100,265), according to the two-point straight line formula, we can get: V-5) / (C-0)=(265-5) / (100-0), where C is the current original value of oxygen concentration, and V is the current collection voltage, thereby obtaining the calculation formula of the original value of oxygen concentration: C=(V-5) / 2.6.

[0062] In one of the embodiments, the calibration coefficient is obtained by the formula: K=20.9 / C1, wherein C1 is the average value of the original value of the oxygen concentration within a preset time, K is the calibration coefficient, and 20.9 is the normal oxygen concentration value in the atmosphere.

[0063] In one embodiment, the calculation formula of the actual value of oxygen concentration is: C2=K*C, wherein C2 is the actual value of oxygen concentration and K is the calibration coefficient.

[0064] It should be understood that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. For those skilled in the art, the technical solutions described in the above embodiments can be modified, or some of the technical features therein can be replaced by equivalents; and all these modifications and replacements should fall within the protection scope of the claims attached to the present invention.

Claims

1. A SF6 detection system, characterized in that: include: A host, a PoE switch and multiple sensors; the PoE switch includes multiple network ports, the host and the multiple sensors are respectively connected to different network ports of the PoE switch for wired communication between the host and the multiple sensors; the host is provided with a first wireless communication module for wireless communication with a server and the multiple sensors; each of the sensors is provided with a second wireless communication module for wireless communication with the server and the host.

2. The SF6 detection system according to claim 1, characterized in that: The host is also provided with a main control module and a display module. The main control module is connected to the first wireless communication module, and the display module is connected to the main control module.

3. The SF6 detection system according to claim 2, characterized in that: The main control module is equipped with the Dianhong IoT operating system.

4. The SF6 detection system according to claim 1, characterized in that: The PoE switch adopts the IPV6 protocol.

5. The SF6 detection system according to claim 1, characterized in that: The plurality of sensors include a SF6 sensor, an oxygen sensor, a temperature sensor, and a humidity sensor.

6. The SF6 detection system according to claim 5, characterized in that: The oxygen sensor includes a voltage follower circuit, a sensor module, a conversion circuit and an amplifier circuit. The output end of the voltage follower circuit is connected to the input end of the sensor module, and the input end of the conversion circuit is connected to the output end of the sensor module to convert the current signal into a voltage signal. The output end of the conversion circuit is connected to the input end of the amplifier circuit, and the output end of the amplifier circuit is connected to the host for ADC sampling.

7. A sensor calibration method, characterized in that: Used to calibrate the oxygen sensor as described in any one of claims 5-6, comprising the following steps: Obtain the relationship curve between voltage and oxygen concentration value under standard conditions; According to the relationship curve and the current acquisition voltage, the current original value of oxygen concentration is obtained; Obtain the average value of the original value of oxygen concentration within the preset time, and calibrate it with the normal oxygen concentration value in the atmosphere to obtain the calibration coefficient; The actual value of the calibrated oxygen concentration is calculated based on the calibration coefficient and the current original value of the oxygen concentration.

8. The sensor calibration method according to claim 7, characterized in that: The calculation formula of the original value of oxygen concentration is: C=(V-5) / 2.6, wherein C is the current original value of oxygen concentration, and V is the current acquisition voltage.

9. The sensor calibration method according to claim 8, characterized in that: The calibration coefficient is obtained by the formula: K=20.9 / C1, wherein C1 is the average value of the original value of the oxygen concentration within a preset time, and K is the calibration coefficient.

10. The sensor calibration method according to claim 7, characterized in that: The calculation formula of the actual value of oxygen concentration is: C2=K*C, wherein C2 is the actual value of oxygen concentration and K is the calibration coefficient.

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