Explosion-proof grounding resistance on-line monitoring system and device

Abstract

The invention discloses an explosion-proof grounding resistance on-line monitoring system and device, and relates to the technical field of grounding resistance monitoring. Comprising a grounding loop, a resistance monitoring device and an intelligent control platform, wherein the grounding loop is formed by a metal grounding electrode, a connecting conductor and to-be-protected equipment; the resistance monitoring device obtains a real-time resistance value of the loop, so that the resistance fluctuation state in unit time is monitored on line in a full-dimension manner; and the intelligent control platform communicates with the resistance monitoring device through a local area network, and transmits the resistance value of the grounding loop to the intelligent control platform for monitoring and displaying. According to the invention, a full-chain digital intelligent lightning safety protection comprehensive solution covering sensing, transmission, analysis, decision making and disposal is created, grounding system detection normalization is realized, a traditional lightning protection grounding system monitoring mode is promoted to be transformed and upgraded to be intelligent, the lightning protection and disaster reduction working level is improved, and lightning protection is transformed from passive protection to active defense.

Description

Technical Field

[0001] This invention relates to the field of grounding resistance monitoring technology, and more specifically, to an explosion-proof grounding resistance online monitoring system and device. Background Technology

[0002] In flammable and explosive environments such as oil tanks and substations, grounding resistance is a key parameter to ensure the safe operation of electrical equipment, and the stability of the grounding system is directly related to the safety and explosion-proof performance of the equipment.

[0003] Existing grounding resistance monitoring technologies mostly rely on manual on-site testing, which has the following shortcomings: First, the testing cycle is long, efficiency is low, and the grounding system status cannot be monitored in real time. Second, traditional monitoring equipment lacks explosion-proof design, making it difficult to meet the needs of flammable and explosive environments such as chemical plants and oil depots. Third, existing monitoring methods can only achieve data collection, failing to form a complete chain of control from data collection to problem handling, resulting in the inability to detect and address potential grounding system hazards in a timely manner, and lightning protection remaining in a passive state.

[0004] Therefore, the existing technology has problems and needs further improvement and development. Summary of the Invention

[0005] (I) Purpose of the invention: In order to solve the problems existing in the prior art, the purpose of the present invention is to provide an explosion-proof grounding resistance online monitoring system and device, which realizes real-time monitoring and intelligent handling of the grounding system through integrated explosion-proof design, non-contact precision measurement, multi-mode communication and cloud intelligent management and control.

[0006] (II) Technical Solution: In order to solve the above technical problems, this technical solution provides an explosion-proof grounding resistance online monitoring system, including a grounding loop formed by a metal grounding electrode, a connecting conductor and the equipment to be protected, as well as a resistance monitoring device and an intelligent control platform; The resistance monitoring device integrates a current transformer and a control module. The control module sends an excitation pulse signal command to the current transformer, receives the pulse potential E and the loop current I generated by the grounding loop, and calculates the real-time resistance value of the loop by R=E / I, thereby obtaining the resistance fluctuation state per unit time and monitoring the resistance value of the grounding loop in all dimensions online. The intelligent control platform communicates with the resistance monitoring device via a local area network, transmitting the real-time resistance value of the grounding circuit to the intelligent control platform for monitoring and display.

[0007] Preferably, the equipment to be protected includes the oil tank body and the substation.

[0008] Preferably, the bottom of the oil tank body is provided with at least one grounding electrode, which is connected to the metal shell of the oil tank body and the resistance monitoring device through a connecting conductor to form a grounding circuit.

[0009] Preferably, the resistance monitoring device body is provided with a ground wire through hole. During installation, the ground wire passes through the ground wire through hole and is connected in series to the grounding loop. The loop method is used to measure the connection status of the online monitoring lead-in, the loop grounding resistance, and the metal loop connection resistance.

[0010] Preferably, the resistance monitoring device is equipped with an LCD display screen, and integrates a current transformer, an independent battery module, a multi-communication module, and a control module; the current transformer sends an excitation pulse signal and receives the electrical signal from the grounding loop, thereby obtaining the resistance value of the grounding loop; The independent battery module provides power to the resistance monitoring device, ensuring its normal operation. The multi-communication module uploads data such as resistance value, grounding status information, and device battery voltage processed by the control module to the intelligent control platform to realize remote data transmission. The control module connects the current transformer, the independent battery module, and the multi-communication module. It is used to control the current transformer to send excitation pulse signals to the grounded circuit under test, collect the induced potential and current of the circuit, calculate the circuit resistance value, and monitor the voltage status of the independent battery module in real time.

[0011] Preferably, the control module sends an excitation pulse signal command to the current transformer, receives the pulse potential E and the loop current I generated by the grounding loop, and calculates the loop resistance value using the formula R=E / I; when an abnormality occurs, an alarm command is triggered, and the corresponding alarm symbol is displayed on the LCD screen.

[0012] Preferably, the intelligent control platform includes a data receiving module, a data processing module, a display module, and a decision alarm module; the data receiving module enables stable reception of multi-source data; The data processing module performs in-depth data processing using an algorithm model; The display module provides users with an intuitive operating interface and a data display medium; The decision alarm module performs intelligent analysis and generates action instructions based on the analysis results.

[0013] Preferably, the data processing module first cleans the data, and then performs calculations, trend analysis, and anomaly identification on all the cleaned data. The trend analysis captures the changing patterns of grounding resistance through multi-dimensional comparison of historical and real-time data, generates a trend hazard association table, and identifies potential hazards in advance. The anomaly identification process involves identifying abnormal data based on a preset threshold, generating a trend analysis report based on the abnormal data, and pushing the trend analysis report to the decision alarm module to trigger an alarm notification.

[0014] Preferably, the data processing module also integrates a multi-monitoring point correlation analysis submodule, including source comparison, time sequence tracing, and path generation; by comparing the resistance change trend, connection resistance difference, and anomaly occurrence sequence of multiple monitoring points in the same grounding system, the root cause of the grounding system fault is automatically located, and a targeted troubleshooting path is generated.

[0015] Preferably, the intelligent control platform uses a block-based reference counting pool to allocate memory for real-time data streams. The underlying system divides the real-time resistance data received by the application layer system into fixed blocks according to integer multiples of the input or output buffer. An initial reference count is bound to each block. When a block is referenced, the reference count is incremented by 1. After processing, the reference count is decremented by 1. When the reference count drops to 0, the block is recycled for reuse, and invalid data is marked. The underlying system uses a dual-end stack allocator to integrate the block pool and historical data management. The bottom stack stores historical data, including the baseline of the trend and hidden danger correlation table and the long-term benchmark value of the monitoring point; the top stack stores real-time data. After each round of comparison between historical data and real-time data is completed, the top stack is released to the preset mark position.

[0016] Preferably, the resistance monitoring device further includes a sensing unit, a triggering unit, and a compensation execution unit; the sensing unit senses environmental parameters of the monitoring environment, and when the sensing unit detects that the environmental parameters exceed a preset threshold, it sends a resistance switching trigger signal; the triggering unit receives the resistance switching trigger signal and converts it into mechanical displacement, which is then transmitted to the compensation execution unit; the compensation execution unit dynamically corrects the measured grounding resistance value.

[0017] An explosion-proof grounding resistance online monitoring device includes any one of the explosion-proof grounding resistance online monitoring systems described above.

[0018] (III) Beneficial Effects: The explosion-proof grounding resistance online monitoring system and device of this invention firstly adopts an integrated explosion-proof design and IP67 protection level, which can operate safely and stably in flammable, explosive, and harsh environments, thus broadening the applicable scenarios for grounding resistance monitoring; secondly, it adopts a non-contact loop measurement method with the ground wire installed through the core, which does not affect the normal operation of the grounding system, and has a short single measurement time, high measurement accuracy, and high efficiency, realizing real-time monitoring of grounding resistance; thirdly, it supports multi-dimensional monitoring and multi-mode communication, and can collect resistance parameters, connection status, anti-theft status, and battery status data, and realize remote data transmission through LoRa, taking into account both local data management and remote monitoring needs; finally, it constructs a full-chain intelligent management and control process, and through big data analysis and intelligent decision-making, realizes accurate identification, timely early warning, and rapid handling of grounding system hazards, promotes the transformation of lightning protection from passive protection to active defense, and improves the systematization, refinement, and scientific level of lightning protection and disaster reduction work. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of an online monitoring system for explosion-proof grounding resistance according to the present invention; Figure 2 This is a schematic diagram of the structure for monitoring the grounding of oil tanks; Figure 3 This is a structural diagram of a resistance monitoring device; Figure 4 This is a schematic diagram of the resistance monitoring device; Figure 5 This is a schematic diagram of the internal structure of a resistance monitoring device for resistance compensation. Figure 6 This is a structural schematic diagram of the mechanical transmission component; Figure 7 This is a schematic diagram of the compensation execution unit; Figure 8 This is a basic schematic diagram of a resistance monitoring device for measuring grounding resistance.

[0020] Reference numerals: 1-Sensing unit, 11-Probe module, 121-pH value detection submodule, 122-Chloride ion concentration detection submodule, 123-Oxidation-reduction potential detection submodule, 21-Drive assembly, 211-Electromagnetic push rod, 22-Trigger unit, 221-Rigid connecting rod, 222-Eccentric cam, 223-Eccentric camshaft, 23-Reset assembly, 3-Compensation execution unit, 31-Compensation element network, 32-Silver relay contact, 33-Copper foil circuit. Detailed Implementation

[0021] The present invention will be further described in detail below with reference to preferred embodiments. More details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention can obviously be implemented in many other ways different from those described herein. Those skilled in the art can make similar extensions and derivations based on actual application situations without departing from the spirit of the present invention. Therefore, the scope of protection of the present invention should not be limited by the content of this specific embodiment.

[0022] The accompanying drawings are schematic diagrams of embodiments of the present invention. It should be noted that these drawings are for illustrative purposes only and are not drawn to scale, and should not be construed as limiting the actual scope of protection of the present invention.

[0023] An online monitoring system for explosion-proof grounding resistance is available, suitable for online monitoring of loop grounding resistance, metallic loop connection resistance, grounding status, and cable anti-theft. It is adaptable to large-scale grounding grid scenarios and single-point grounding systems, and is particularly suitable for flammable, explosive, and harsh outdoor environments. Figure 1As shown, the system includes a resistance monitoring device and an intelligent control platform. The resistance monitoring device monitors the real-time resistance value of the grounding loop in all dimensions online, thereby obtaining the resistance fluctuation status per unit time. The intelligent control platform communicates with the resistance monitoring device via a local area network, transmitting the real-time resistance value of the grounding loop to the intelligent control platform for monitoring and display. This enables accurate identification and rapid handling of potential grounding system hazards, promoting the transformation of lightning protection from passive protection to active defense.

[0024] The grounding circuit includes a metal grounding electrode, a connecting conductor, and the equipment to be protected, which are connected in series to form the grounding circuit. The grounding circuit is used to discharge fault current, ensure equipment safety, and provide a reference for resistance measurement.

[0025] The metal grounding electrode serves as the grounding terminal of the grounding circuit. By making low-impedance contact with the soil, it discharges the fault current to the ground, preventing the casing of the protected equipment from becoming energized or generating sparks.

[0026] The metal grounding electrode is made of T2 copper or 6061 aluminum alloy. Copper is preferred for explosion-proof environments to avoid corrosion of aluminum in acidic soil. The surface is treated with hot-dip galvanizing and graphene composite coating, with a zinc layer thickness ≥85μm and a coating salt spray resistance ≥5000 hours.

[0027] The metal grounding electrode includes a vertical grounding electrode, a horizontal grounding conductor, and a corrosion-resistant reinforcement structure. The vertical grounding electrode is a solid rod with a diameter of 14–20 mm and a length of 2.5–3 m, with a tapered bottom to reduce soil penetration resistance. The horizontal grounding conductor is a flat or round steel bar with a cross-sectional area of ​​50–120 mm², buried at a depth of 0.8–1.2 m, and arranged radially or in a grid pattern. The corrosion-resistant reinforcement structure includes pre-fabricated spiral grooves on the entire surface of the metal grounding electrode. The spiral grooves are 0.5 mm deep with a pitch of 10 mm and filled with bentonite resistance-reducing agent to lower the contact resistance with the soil and slow down corrosion.

[0028] The connecting conductor connects the metal grounding electrode, the device to be protected, and the measurement node of the resistance monitoring device, forming a closed grounding loop and providing a physical path for resistance monitoring. The connecting conductor transmits the fault current of the device to be protected to the metal grounding electrode without attenuation, ensuring that the casing voltage of the device to be protected is less than the safety threshold during a fault.

[0029] The connecting conductor comprises a main conductor and branch conductors. The main conductor is made of T2 copper strip with a thickness ≥3mm or copper-clad steel stranded wire with a cross-sectional area ≥50mm², possessing high conductivity and mechanical strength. The branch conductors are multi-strand copper core cables with a cross-sectional area of ​​16–35mm², sheathed with a flame-retardant PVC insulation layer, capable of withstanding temperatures from -40℃ to +105℃. The buried portion of the connecting conductor is run through a CPVC conduit, while the surface portion is encased in a stainless steel corrugated conduit for protection.

[0030] The connecting conductor and the metal grounding electrode are connected by exothermic welding, with a weld overlap length ≥100mm and a resistivity at the weld ≤1.2 times that of the original conductor. It is connected to the equipment to be protected via copper bolts, with the contact surface tin-plated to a thickness ≥5μm.

[0031] The equipment to be protected includes the oil tank body and the substation. At least one grounding electrode is installed at the bottom of the oil tank body, such as... Figure 2 As shown, the metal conductor is electrically connected to the metal shell of the oil tank body. Through reliable grounding, static electricity and fault current are quickly discharged, avoiding explosion caused by sparks due to potential difference. The fault voltage of the equipment shell is limited to a safe range to prevent electric shock to personnel or damage to equipment.

[0032] Specifically, this invention arranges 4 to 6 vertical grounding electrodes evenly along the circumference of the bottom of the oil tank, connected by a horizontal ring conductor to form a ring and radial composite grounding network. The tank wall is connected to the grounding conductor using flexible copper braids, the cross-sectional area of ​​which is 50 mm² and the length is ≥300 mm, to absorb the displacement stress caused by the thermal expansion and contraction of the oil tank.

[0033] The substation uses a grid-like horizontal grounding electrode, which is made of 50×5mm galvanized flat steel, forming a grid size of 5m×5m. Vertical grounding electrodes are installed at the intersections of the grid, and lightning rods are installed at the edges. The grounding grids of the equipment area, high-voltage area, and low-voltage area are separated by insulated connectors to avoid interference between different systems.

[0034] like Figure 3 , Figure 4 As shown, the overall dimensions of the resistance monitoring device are 205mm × 223mm × 168mm, facilitating on-site installation. The device itself is equipped with a 47×28.5mm LCD display screen for displaying measured values, resistance units, alarm symbols, low battery voltage symbols, and stored data group numbers.

[0035] The resistance monitoring device also features a grounding wire through-hole measuring 51mm x 27mm. During installation, the grounding wire passes through this hole and is connected in series to the grounding loop. The loop method is used to measure the connection status of the online monitoring down conductor, the loop grounding resistance, and the metal loop connection resistance. This non-contact measurement method does not affect the normal operation of the lightning protection grounding facilities. The device's explosion-proof marking is ExdbmbIIBT6Gb, meeting the safety requirements for flammable and explosive environments. With an IP67 protection rating, it possesses excellent waterproof, dustproof, and corrosion-resistant capabilities, and can operate stably in harsh environments ranging from -20℃ to 55℃ and 20%RH to 90%RH, making it suitable for outdoor and complex industrial scenarios.

[0036] The resistance monitoring device integrates a current transformer, an independent battery module, a multi-communication module, and a control module. The current transformer sends an excitation pulse signal and receives the electrical signal from the grounding loop, thereby obtaining the resistance value of the grounding loop. The independent battery module provides power to the resistance monitoring device, ensuring normal operation. The multi-communication module uploads data such as the resistance value, grounding status information, and device battery voltage processed by the control module to the intelligent control platform, realizing remote data transmission. The control module connects the current transformer, the independent battery module, and the multi-communication module, and is used to control the current transformer to send an excitation pulse signal to the grounding loop under test, collect the induced potential E and current I of the loop, calculate the loop resistance value, and monitor the voltage status of the independent battery module in real time. The current transformer, independent battery module, multi-communication module, and control module work together to achieve accurate monitoring, data transmission, and intelligent operation of the grounding system.

[0037] Specifically, the current transformer outputs a specific excitation pulse signal to the grounding circuit under test according to the instructions of the control module. Under the action of the excitation pulse signal, the pulse potential E and circuit current I generated by the induced grounding circuit are converted into measurable electrical signals and transmitted to the control module. This provides core data support for resistance value calculation and is the basis for realizing accurate measurement of circuit grounding resistance and metal circuit connection resistance.

[0038] The independent battery module outputs a stable 7.2VDC voltage, providing power support for the operation of all components, including the current transformer, control module, multi-communication module, and LCD display, ensuring continuous power supply for the equipment. The independent battery module adopts a modular design, separate from the motherboard, and can be individually disassembled and replaced without requiring complete equipment disassembly, reducing maintenance costs and downtime. It incorporates a built-in voltage detection adapter structure, providing real-time feedback on its own voltage usage and transmitting battery status data to the control module for easy background monitoring and low-battery warnings, preventing monitoring signal interruption due to insufficient power.

[0039] The multi-communication module uploads the resistance value, grounding status information, and device battery voltage processed by the control module to the LoRa gateway in real time, enabling remote data transmission. The communication distance can reach 3km in open line-of-sight environments. The multi-communication module employs low-power wireless communication technology, adapting to industrial scenarios and outdoor environments, ensuring reliable data transmission and supporting remote real-time monitoring.

[0040] The multi-communication module communicates with the intelligent control platform via LoRa as the basic communication module. It can be used with a smart IoT gateway to achieve protocol conversion and supports expansion to other communication methods such as Ethernet, 4G, and TCP / WiFi, adapting to remote monitoring needs in different scenarios. The resistance monitoring device communicates with the intelligent control platform via a local area network, uploading the sensed resistance data, status information, and battery voltage data to the intelligent control platform in real time, facilitating data upload and cascading expansion. It can also be expanded to support other communication methods such as Ethernet and 4G. LoRa, based on LoRa radio frequency technology, uses wireless radio frequency signals and is suitable for low-power, long-distance wireless communication scenarios. Ethernet uses Cat5e / Category 6 network cables to achieve stable local area network communication via a wired network, and must comply with explosion-proof area wiring specifications. 4G uses mobile cellular networks, utilizing mobile operator networks to achieve wide-area coverage remote communication, but relies on operator network coverage.

[0041] The resistance monitoring device can also use AES-128 symmetric encryption to encrypt the transmitted data before transmitting it to the intelligent control platform, ensuring the confidentiality and integrity of the data transmission.

[0042] The control module is the core management unit of the resistance monitoring device, encompassing the entire process of measurement, storage, display, and alarm. It sends excitation pulse signals to the current transformer, schedules data uploads via the multi-communication module, controls the content displayed on the LCD screen, and coordinates the orderly operation of all modules. The control module receives the raw E and I signals transmitted from the current transformer, calculates the loop resistance value using the formula R=E / I, and performs preliminary data processing to filter valid data. It monitors the grounding system status and the device's own status in real time, triggering alarm commands when an anomaly occurs and controlling the LCD screen to display the corresponding alarm symbol. It also supports local data storage commands, using the data storage unit to retain historical monitoring data, while simultaneously synchronizing key data to the LCD screen and the multi-communication module, achieving dual data management through local visualization and remote transmission.

[0043] The resistance monitoring device uses the loop method to measure the loop grounding resistance value, with a range covering 0.01Ω to 100Ω and a resolution of 0.001Ω. A single measurement takes only about 0.5 seconds and can accurately capture minute changes in grounding resistance with an accuracy that meets the ±2%rdg±3dgt standard.

[0044] The resistance monitoring device can also detect the transition resistance between the grounding down conductor and the grounding grid, metal overhead lines, etc., to determine whether there are problems such as loose connections or poor contact at the connection points. Specifically, it indirectly determines whether the down conductor is loosely connected or broken by observing changes in resistance, preventing grounding system failure due to connection failure. If the cable is cut, the resistance of the metal loop will suddenly become infinite, and the LCD screen will display 0Ω, with the command reading value corresponding to 500Ω, providing a clear indication of a grounding system abnormality, and the device will immediately trigger an alarm.

[0045] like Figure 5 As shown, the resistance monitoring device further includes a sensing unit, a triggering unit, and a compensation execution unit; the sensing unit senses environmental parameters of the monitoring environment, including at least one physical or chemical parameter, and sends a resistance switching trigger signal when the sensing unit detects that the environmental parameter exceeds a preset threshold.

[0046] The sensing unit includes a probe module and a detection module integrated with the probe module to monitor environmental parameters. The detection module includes a pH detection submodule, a chloride ion concentration detection submodule, and a redox potential detection submodule, which collects soil environmental parameters in real time. These environmental parameters include soil pH, chloride ion concentration, and redox potential.

[0047] Each detection submodule has a preset trigger threshold. The trigger threshold for the pH detection submodule is pH < 5.0; the trigger threshold for the chloride ion concentration detection submodule is chloride ion concentration > 300 mg / L; and the trigger threshold for the redox potential detection submodule is when the redox potential is < -400 mV, at which point a coordinated trigger signal is output and superimposed on the resistance switching trigger signal.

[0048] Specifically, when the pH value detected by the pH detection submodule is less than 5.0, a resistance switching trigger signal is output. The strength of the resistance switching trigger signal is negatively correlated with the pH value. Specifically, for every 1.0 decrease in pH, the resistance switching trigger signal strength increases by 1V.

[0049] When the chloride ion concentration detected by the chloride ion concentration detection submodule is >300 mg / L, a resistance switching trigger signal is output. The strength of the resistance switching trigger signal is positively correlated with the concentration. Specifically, for every 100 mg / L increase in concentration, the resistance switching trigger signal strength increases by 2 mA. When the redox potential detected by the redox potential detection submodule is < -400mV, a coordinated trigger signal is output. The coordinated trigger signal is superimposed with the resistance switching trigger signal, and the total signal strength = resistance switching trigger signal + coordinated trigger signal, which drives the trigger unit to switch the resistance, and the corresponding displacement increases linearly.

[0050] The triggering unit includes a driving component 21, a mechanical transmission component 22, and a reset component 23. The driving component 21 receives a resistance switching trigger signal and converts it into mechanical displacement. The mechanical transmission component 22 transmits the mechanical displacement to the compensation execution unit, and the mechanical transmission component 22 is rigidly connected to the driving component 21. The reset component 23 drives the mechanical transmission component 22 to return to its initial position after the resistance switching trigger signal disappears.

[0051] The driving component 21 includes an electromagnetic push rod 211 mounted on the probe module of the sensing unit. The displacement of the electromagnetic push rod 211 is linearly related to the strength of the resistance switching trigger signal output by the detection module. An increase of 1V or 2mA in the resistance switching trigger signal strength corresponds to a 1mm increase in the axial displacement of the electromagnetic push rod 211; for example, a 3V signal corresponds to a 3mm displacement, and a 10mA signal corresponds to a 5mm displacement. The maximum stroke of the electromagnetic push rod 211 is 8mm, and the thrust is not less than 10N. When the electromagnetic push rod 211 is at its maximum stroke, the corresponding pH detection submodule detects a pH of 0, or the chloride ion concentration detection submodule detects a chloride ion concentration of 1000mg / L.

[0052] like Figure 6 As shown, the mechanical transmission assembly 22 includes an eccentric cam 222 and a rigid connecting rod 221. The eccentric cam 222 is rigidly connected to the eccentric camshaft 223 via a keyway. The eccentric camshaft 223 is connected to the rigid connecting rod 221 via a reset assembly 23. At least three sets of contact points are provided on the outer periphery of the eccentric cam 222. One end of the rigid connecting rod 221 is hinged to the bottom end of the electromagnetic push rod 211 via a ball joint, and the other end is fitted onto the eccentric pin of the eccentric camshaft 223 via an interference fit. The eccentric cam is rotated by the displacement of the electromagnetic push rod 211.

[0053] When the electromagnetic push rod 211 is axially displaced by 3mm, the rigid connecting rod 221 pushes the eccentric cam shaft 223 to produce radial displacement, driving the eccentric cam 222 to rotate counterclockwise by 12° around the eccentric cam shaft 223, and the first set of flanges on the outer periphery of the eccentric cam 222 contacts the contact point. When the electromagnetic push rod 211 is axially displaced by 5mm, the rotation angle of the eccentric cam 222 increases to 20°, the second set of flanges on the outer periphery of the eccentric cam 222 contacts the contact point, and at this time, the storage torque of the reset assembly 23 increases.

[0054] The rigid connecting rod 221 is made of stainless steel, which is high in strength and not easily corroded.

[0055] The reset assembly 23 is sleeved on the end of the eccentric camshaft. One end is rigidly connected to the eccentric camshaft via a keyway, and the other end is fixed to the housing bracket via a locating pin. The initial preload torque can be precisely set by rotating the adjusting nut of the locating pin on the housing bracket. The adjustment range is ±0.5 N·mm to ensure the consistency of reset assemblies from different batches.

[0056] The reset component is preferably a reset spring, and in this invention, 316L stainless steel wire is used. The 316L stainless steel wire contains molybdenum and exhibits a corrosion rate of ≤0.01mm per year in environments with a soil chloride ion concentration ≤300mg / L and a pH value of 5.0~8.0, demonstrating strong corrosion resistance and suitability for humid and salt-spray environments such as oil tank areas and substations. Furthermore, after low-temperature aging treatment, the 316L stainless steel wire has a fatigue limit ≥800MPa, meeting the requirements for cyclic switching.

[0057] The compensation execution unit includes a compensation element network, which is connected in series with the resistance measurement branch of the grounding loop to achieve dynamic correction of the grounding resistance measurement value.

[0058] The compensation execution unit is linked with the mechanical conduction component and includes at least two types of compensation resistors with preset resistance values. The measured grounding resistance value = actual grounding resistance - compensation resistor value. The actual grounding resistance refers to the true contact resistance between the metal grounding electrode and the soil, that is, the total resistance encountered when current flows from the metal grounding electrode into the soil and diffuses. Ideally, the actual grounding resistance is equal to the sum of the inherent resistance of the metal grounding electrode and the soil current dissipation resistance; however, under the current soil environment, the true contact resistance value after considering factors such as soil corrosion and changes in environmental parameters is the core indicator of the safety performance of the grounding system. When the compensation element network switches between compensation resistors with different resistance values, a contact design of "on first, off later" is adopted to ensure that the measurement branch is always conductive during the switching process, avoiding open-circuit sparks.

[0059] In this invention, such as Figure 7 As shown, the compensation execution unit includes three high-precision metal film resistors R1, R2, and R3. The nominal resistance values ​​of the metal film resistors are R1=0Ω, R2=1Ω, and R3=5Ω. The rated power of the metal film resistors is not less than 0.25W, the temperature coefficient is ≤±50ppm / ℃, and the accuracy class is ±0.1%. The input terminals of each resistor are electrically connected to the outer flange of the eccentric cam through silver relay contacts, and the output terminals are connected in series to the differential voltage sampling point of the resistance measurement branch through copper foil lines. The resistance measurement branch corrects the measurement deviation caused by soil corrosion by switching the resistance value.

[0060] The metal film resistor employs a composite structure of a nickel-chromium alloy film and a ceramic substrate. The nickel-chromium alloy film exhibits a low temperature coefficient, while the ceramic substrate has a high degree of thermal expansion matching with the metal film, reducing resistance stress drift caused by material deformation during temperature changes. The copper foil circuit connected in series at the output of the compensation element network is made of highly conductive oxygen-free copper, with a temperature coefficient of approximately 0.00393 / ℃. By complementing the temperature characteristics of the copper foil circuit and the metal film resistor, the temperature influence on the total resistance of the resistance measurement branch is further reduced.

[0061] When the ambient temperature varies within the range of -20℃ to +60℃, the coverage system can adapt to the extreme ambient temperature range of actual applications, including outdoor or underground soil temperature variations in environments such as oil tank areas and substations. This avoids abnormal drift in the resistance value of the metal film resistor caused by low-temperature freeze-thaw cycles or high-temperature exposure. A 0Ω resistor serves as the normal measurement reference, with actual resistance fluctuation ≤ ±5mΩ, ensuring no interference from additional resistors under reference conditions. A 1Ω or 5Ω resistor serves as the core component for dynamic correction, with actual resistance fluctuation ≤ ±0.01Ω.

[0062] The contact resistance of the silver relay contacts is ≤10mΩ, and the contact bounce time is <5ms during the eccentric cam rotation switching process, effectively avoiding interruption of the measurement signal.

[0063] The eccentric cam switches between different resistance values ​​when rotating to achieve dynamic compensation. For example, it connects to 1Ω for mild corrosion, 5Ω for severe corrosion, and 0Ω in the initial state to ensure the measurement reference.

[0064] Specifically, when the detection module has no resistance switching trigger signal, the eccentric cam is at the 0° position, the compensation element network is in its initial state, and a 0Ω resistor is connected to the resistance measurement branch. When the pH value is <5.0 or the chloride ion concentration is >300mg / L, the compensation element network performs slight compensation, the eccentric cam rotates 12°, and a 1Ω resistor is connected to the resistance measurement branch. When the pH value is <5.0, the chloride ion concentration is >300mg / L, and the redox potential is <-400mV, the compensation element network performs heavy compensation, the eccentric cam rotates 20°, and a 5Ω resistor is connected to the resistance measurement branch.

[0065] The compensation execution unit ensures that when the resistance monitoring device is located in a flammable or explosive area, the transition resistance value of the grounding circuit is always less than or equal to the first threshold, thus ensuring the safety of the protected equipment and meeting industry standards.

[0066] In this invention, the first threshold is preferably 0.03Ω.

[0067] The environmental parameters of the sensing unit and the grounding resistance value of the compensation execution unit are transmitted to the intelligent control platform for display via the Internet of Things (IoT). The intelligent control platform includes a cloud platform and a local area platform. The intelligent control platform communicates with the resistance monitoring device via a local area network, transmitting the resistance value of the grounding loop to the intelligent control platform for display.

[0068] The intelligent control platform is the data hub, comprising a data receiving module, a data processing module, a display module, and a decision-making alarm module. It is an integrated digital intelligence system that combines hardware adaptation, software modules, and functional algorithms. The data receiving module is responsible for data reception and protocol adaptation, serving as a bridge between the intelligent control platform and the resistance monitoring device. Its core function is to achieve stable access and format unification of multi-source data. The data processing module is responsible for core algorithms and logical operations, performing in-depth data processing through algorithmic models, and is the core of the intelligent control platform's intelligent judgment. The display module provides users with an intuitive operating interface and data display platform. The decision-making alarm module performs intelligent judgment based on the analysis results and generates action commands.

[0069] The data receiving module has high-concurrency data receiving capabilities, receiving in real time data uploaded by the resistance monitoring device, such as loop grounding resistance value, metal loop connection resistance value, grounding status, cable integrity, and battery voltage. It also supports local data retransmission in the event of a network interruption.

[0070] The data receiving module includes a LoRa receiving submodule, an extended communication interface submodule, and a data decoding submodule. The LoRa receiving submodule is the main communication channel. The extended communication interface submodule is selectable and includes one or more of Ethernet / RJ45 and 4G / SIM card slots. The data decoding submodule performs verification and validation.

[0071] The data receiving module receives all data sent by the resistance monitoring device, including loop grounding resistance value, metal loop connection resistance value, grounding status indicator, cable integrity signal, battery voltage data, device number, and acquisition timestamp, as well as real-time values ​​of soil pH, chloride ion concentration, and redox potential; it decodes and verifies the integrity of the received wireless / wired signals to ensure data accuracy.

[0072] The integrity check refers to checking whether the data fields are complete. If any field is missing, it is marked as incomplete data, temporarily stored in a temporary cache, and a retransmission request is sent. If the retransmission fails, the missing field information is recorded and archived. Valid data that passes the check is encapsulated according to a unified data structure, including fields such as basic information, core data, and check identifier.

[0073] The basic information includes device ID, monitoring point location, and data collection time. The core data includes resistance value and battery voltage. The verification identifier includes pass / fail.

[0074] The data processing module first cleans the data, then performs calculations, trend analysis, and anomaly identification on all the cleaned data, including restoring the actual grounding resistance and multi-dimensional anomaly judgment.

[0075] The data cleaning refers to removing noisy data and correcting biased data based on preset measurement accuracy standards and data rationality rules to ensure the accuracy of the analyzed data.

[0076] Specifically, according to the formula Actual grounding resistance = Measured branch resistance value + Current compensation resistance value, combined with environmental parameters, the measurement deviation is dynamically corrected to restore the actual grounding resistance, ensuring that the error between the result and the true grounding resistance is ≤ ±0.01Ω.

[0077] An anomaly is marked when the transition resistance value exceeds the first threshold. Corrosion risk is marked when the pH value is less than 5.0, the chloride ion concentration is greater than 300 mg / L, or the redox potential is less than -400 mV. A fault is marked when the battery voltage is less than the low charge threshold or communication interruption lasts for more than 5 minutes; a fault log is generated when the compensation resistor switching fails.

[0078] Specifically, the sensor first sends an excitation pulse signal to the grounded circuit under test, inducing a pulse potential E in the circuit. Under the action of the pulse potential E, a current I is generated in the circuit. The sensor measures the pulse potential E and the current I, and the resistance value of the circuit under test can be obtained using the formula: R=E / I.

[0079] The intelligent control platform displays the loop resistance. Based on the loop resistance value, it determines whether the equipment to be protected is in a flammable or explosive hazardous environment. For example... Figure 8 As shown, the loop resistance includes the combined value of the grounding resistance at point A to ground, the resistance of the grounding down conductor, the resistance of the overhead metal line, the connection resistance between the grounding down conductor and the overhead metal line, and the grounding resistance at point B to ground. In other words, the loop resistance value = the transition resistance value of the grounding loop + the grounding resistance value of the compensation execution unit.

[0080] When the loop resistance value R displayed by the intelligent control platform is greater than 0.03Ω, that is, when the loop resistance value R calculated according to the formula R=E / I is greater than 0.03Ω, it indicates that the device to be protected is in a dangerous environment. The grounding resistance value of the compensation execution unit is to ensure the safety of the entire grounding loop and to prevent damage to the grounding loop due to excessive current and / or voltage values ​​in the grounding loop.

[0081] The trend analysis captures the changing patterns of grounding resistance through multi-dimensional comparison of historical and real-time data, and generates a trend hazard association table, as shown in Table 1, to identify potential hazards that may lead to grounding system failure in advance and to predict specific potential problems.

[0082] Table 1. Trend Risk Correlation Table

[0083] The anomaly identification process identifies abnormal data such as resistance overflow, cable breakage, and low battery voltage based on preset thresholds. A trend analysis report is generated based on this anomaly data, including trend charts, rate of change data, predicted hazard types, and risk levels. This trend analysis report is then pushed to the decision alarm module, triggering an alarm notification.

[0084] The data processing module also integrates a multi-monitoring point correlation analysis submodule. By comparing the resistance change trends, connection resistance differences, and anomaly occurrence sequences of multiple monitoring points within the same grounding system, it automatically locates the root cause of the grounding system fault and generates a targeted troubleshooting path.

[0085] Specifically, the working logic of the multi-monitoring point correlation analysis submodule includes source comparison, time-series tracing, and path generation. The source comparison unit calculates the difference in resistance change rate between the main grounding down conductor and each branch grounding down conductor in a large grounding grid. When the change rate of a branch conductor is more than twice that of the main conductor and persists for three consecutive acquisition cycles, the root cause of the fault is determined to be the branch conductor itself or its connection point to the grounding grid. Time-series tracing records the occurrence time of anomalies at multiple monitoring points. If the anomaly spreads in the order from the edge monitoring points to the center monitoring point of the grounding grid, the root cause of the fault is determined to be an overall failure of the grounding grid; if only a single monitoring point exhibits an isolated anomaly, the root cause of the fault is determined to be the down conductor or cable corresponding to that monitoring point. Path generation automatically plans the shortest investigation path based on the location of the fault root cause and the grounding system model, marks key detection nodes, and pushes the path to the display module for display to maintenance personnel.

[0086] To address the practical problems of memory fragmentation, chaotic data lifecycle, inefficient cross-module referencing, and difficulty in anomaly recovery in industrial monitoring scenarios, such as explosion-proof grounding resistance online monitoring systems, this invention also proposes a progressive memory optimization scheme that is suitable for high-frequency real-time monitoring scenarios such as oil tank areas and substations, and solves the memory fragmentation problem caused by high-concurrency data streams.

[0087] The data receiving and scheduling submodule of the application layer of the intelligent control platform receives the real-time resistance data and environmental parameters of the resistance monitoring device, and sends a control command to the underlying system to start the block-based reference counting pool to allocate memory, triggering the underlying memory optimization process.

[0088] The underlying system's memory pool management module, based on received control commands, divides real-time data into fixed-size small blocks at integer multiples of the system's input or output buffer size. Each block is then bound with an initial reference count, and the module monitors the reference count changes in real time. When a block's reference count drops to 0, the block is automatically reclaimed to the memory pool, and invalid data within the block is marked for later reuse, reducing memory fragmentation. The divided blocks are then pushed for trend analysis, anomaly detection, and other business operations.

[0089] Specifically, when the data receiving and scheduling submodule of the intelligent control platform application layer receives real-time resistance data and environmental parameters, it instructs the underlying system's memory pool management module to start allocating memory using a block-based reference counting pool. Specifically, the memory pool management module first divides the real-time resistance data and environmental parameters into fixed-size small blocks, such as 1KB / 4KB, in integer multiples of the system input or output buffer size, to meet the low-latency requirements of explosion-proof scenarios. An initial reference count is bound to each block. When the referenced data undergoes trend analysis or anomaly identification, the reference count is incremented by 1; after processing, the reference count is decremented by 1. When the reference count drops to 0, the block is automatically reclaimed to the memory pool for reuse, and invalid data within the block is marked, reducing memory fragmentation by ≥40% and avoiding repeated loading of the same data unit.

[0090] The underlying system's memory pool management module uses a dual-ended stack allocator to integrate the block pool and historical data management, including a bottom stack and a top stack. The dual-ended stack allocator can handle the allocation of the block-based reference counting pool, storing real-time blocks on the top stack and historical data on the bottom stack. This optimizes data lifecycle management, achieves physical separation of the memory space for temporary real-time data and persistent historical data, avoids interference from temporary data fragments on persistent data, and improves memory utilization.

[0091] The bottom stack stores persistent historical data and manages its lifecycle using reference counting, including the baseline of the trend and hidden danger association table and long-term benchmark values ​​of monitoring points; the top stack stores real-time block data. After each round of comparison and analysis of historical data and real-time data is completed, the top stack is released to a preset mark to keep the memory continuous and free of fragmentation.

[0092] In the multi-monitoring point correlation analysis submodule, the underlying system's memory pool management module constructs a pointer correction table to record the disk offset values ​​and monitoring point IDs of different monitoring point block data. Based on a dual-ended stack memory layout, the underlying system's memory pool management module optimizes cross-monitoring point data referencing efficiency, resolving address lookup bottlenecks during multi-module collaborative analysis. When data is loaded into memory, the underlying system's memory pool management module, combining the dual-ended stack address space, converts the disk offset values ​​in the pointer correction table into actual memory addresses, reducing cross-monitoring point lookup time.

[0093] The pointer correction table relies on the preceding block-based reference counting pool and double-ended stack allocation to form a complete cross-module data reference optimization chain.

[0094] The cross-monitoring point correlation analysis includes multi-dimensional analysis such as source comparison, time-series tracing, and cross-regional collaboration to automatically locate the root cause of grounding faults. Source comparison refers to the horizontal comparison of monitoring data from multiple grounding electrodes within the same area, such as changes in grounding resistance of different tanks in an oil tank area; time-series tracing refers to the vertical correlation of data from the same monitoring point at different time points, such as tracing environmental parameters before and after an abnormal grounding resistance in a substation; and cross-regional collaborative analysis refers to the linked query of monitoring data from different explosion-proof areas, such as the correlation of potential hazards in the grounding systems of different workshops in a chemical plant.

[0095] The underlying system's memory pool management module integrates a pointer correction table and a dual-ended stack to achieve unified management of multi-dimensional analysis results, reducing cross-module data interaction costs. Specifically, the application layer's data receiving and scheduling submodule receives composite analysis results such as trend analysis reports, anomaly identification results, and fault location paths. The underlying system's memory pool management module stores these composite analysis results using globally unique GUID identifiers. The sub-data included in the composite analysis results, such as trend analysis reports, anomaly identification results, and fault location paths, can also be associated through a pointer correction table, reducing cross-module lookup overhead. The composite analysis results are stored in the bottom-end stack and quickly indexed via GUIDs, supporting efficient data sharing under multi-role permission control.

[0096] The underlying system's memory pool management module also periodically generates memory snapshots, which include the chunk pool state, double-ended stack marker bits, pointer correction table, and GUID index. Upon abnormal restart, these memory snapshots automatically restore and rebuild the chunk pool reference count, restore the historical / real-time data partitions of the double-ended stack, and repair the address mapping of the pointer correction table.

[0097] The preferred storage period for the memory snapshot described in this invention is 5 minutes.

[0098] The display module displays data in real time, including 3D modeling of the grounding system and monitoring equipment deployment locations. It intuitively presents the distribution of monitoring points, real-time resistance values, equipment operating status, battery status of the resistance monitoring device, and the power supply of its own intelligent control platform. The display module shows a node diagram of the entire process; clicking on a monitoring location on the node diagram allows viewing detailed data for that location. It provides access points for equipment management, parameter configuration, alarm viewing, and issuing handling commands, and supports multi-role access control. Real-time data is updated every second, and historical data query response time is ≤2 seconds.

[0099] The receiver receives voltage data from the battery status monitoring device and converts the voltage data into a percentage of charge, for example, 7.2V=100%, 6.0V=20%.

[0100] The display module is preferably an industrial touch LCD with an IP65 protection rating for the front panel, suitable for harsh environments outside of explosion-proof areas. The industrial touch LCD supports day and night modes, with night mode reducing brightness to 100 cd / m² to minimize light pollution.

[0101] The display module also automatically generates daily, weekly, and monthly statistical reports, including key indicators such as average resistance value, number of anomalies, and handling completion rate, and supports exporting and printing.

[0102] The decision alarm module provides alarm prompts for abnormal data, including an audible and visual alarm, an alarm triggering submodule, and a log recording submodule. The audible and visual alarm uses an explosion-proof housing, conforms to GB3836.1-2010 standard, and includes a red LED light and a buzzer.

[0103] The decision alarm module has a built-in preset decision rule library. Combining the data results output by the data processing module with the scene type, it automatically generates decision commands and performs tiered alarms, including Level 1, Level 2, and Level 3 alarms. Specifically, when the transition resistance value of the grounding loop is greater than the first threshold, a Level 1 alarm is triggered. At this time, the red LED flashes, the buzzer sounds intermittently, and the display module pops up a red alarm window displaying the current grounding resistance value. When the battery voltage is less than the low battery threshold, a Level 2 alarm is triggered. At this time, the red LED stays on, the buzzer sounds three short beeps, and the display module displays the battery level. When the signal interruption lasts for more than 5 minutes, the red LED flashes, the buzzer sounds a long 10 seconds, and the display module displays a connection interruption.

[0104] Level 1 alarms take precedence over Level 2 alarms, and Level 2 alarms take precedence over Level 3 alarms. When multiple alarms are triggered simultaneously, only the details of the highest priority alarm are displayed.

[0105] When maintenance personnel discover an alarm, they can manually click the button on the display unit to clear it, or the alarm will automatically stop after the abnormal state is restored. The display module automatically retains the alarm log record without manual intervention. As shown in Table 2, the alarm log record mainly includes structured data fields such as event ID, alarm type, trigger time, end time, duration, abnormal parameter value, processing status, and remarks. The alarm log record supports exporting in CSV format, which is convenient for maintenance personnel to analyze offline or archive.

[0106] Table 2 Alarm Log Record Data Fields

[0107] The tank farm monitoring room can analyze historical alarm logs to identify frequent periods of excessive grounding resistance and proactively investigate soil corrosion issues. The substation maintenance center can trace the patterns of communication failures and optimize LoRa network coverage. Safety audits of explosion-proof sites can export historical alarm logs as a basis for grounding system compliance checks, meeting safety production regulatory requirements.

[0108] The alarm log recording is linked with the decision alarm module. When the alarm pop-up window appears on the display module, historical alarm log records are generated simultaneously to ensure that abnormal events are traceable and verifiable, and to support the upgrade of the lightning protection grounding system from passive protection to active defense.

[0109] An explosion-proof grounding resistance online monitoring device includes the aforementioned explosion-proof grounding resistance online monitoring system.

[0110] The following is a detailed description with reference to specific embodiments: Taking the grounding system of a large oil depot as an application scenario, the oil depot adopts an overall large grounding grid design with a maximum diagonal distance of 800 meters. Resistance monitoring devices are installed on the three main grounding down conductors Y1, Y2, and Y3 and the five branch grounding down conductors Z1 to Z5. The monitoring frequency is set to collect data once every 15 minutes. The intelligent control platform identifies potential grounding hazards through trend analysis.

[0111] Because the oil depot is a humid and corrosive environment, the trend analysis automatically removes temporary resistance fluctuation data caused by rainy days, focusing on core hidden dangers such as corrosion of metal parts and loose connections.

[0112] Resistance data for the Y1 lead wire over the past 90 days was extracted from the historical database of the intelligent control platform. Invalid data due to measurement errors and communication interference were removed, leaving 8640 sets of valid data. Real-time data represented the most recently acquired resistance value of 1.12Ω, and environmental data from the same period was extracted simultaneously. The average resistance value over the past 30 days was used as the baseline, with the baseline values ​​for Y1 lead wire being 0.85Ω, Y2 0.78Ω, and Y3 0.92Ω. A daily average resistance change rate ≥0.3% was considered a slow abnormal upward trend, a single-day change rate ≥1% was considered a rapid abnormal upward trend, and fluctuations exceeding ±0.2Ω were considered abnormal fluctuations.

[0113] The real-time resistance value of 1.12Ω was calculated as follows: Subtracting the baseline value of 0.85Ω from the resistance value of the past 30 days resulted in a difference of 0.27Ω. The difference was positive and showed an increasing trend over 15 consecutive measurements, gradually rising from 0.18Ω to 0.27Ω. The daily average change rate over the past 7 days was calculated as follows: (Daily average resistance value - Average resistance value 7 days ago) / Average resistance value 7 days ago × 100% = (1.08Ω - 0.95Ω) / 0.95Ω × 100% ≈ 13.68%, with a daily average change rate of approximately 1.95%, far exceeding the preset warning threshold of 0.3%, indicating a rapid and abnormal upward trend. A linear regression algorithm was used to fit the trend of the effective data from the Y1 line over the past 90 days, generating a linear trend curve y = 0.0032x + 0.61, where x represents the number of days and y represents the resistance value. The curve has a positive slope and a large absolute value, indicating a continuous and rapid upward trend in resistance. Comparing the real-time data of 1.12Ω with the fitted curve's predicted value of 1.05Ω, the real-time value exceeds the predicted value by 0.07Ω, and the real-time data has been higher than the corresponding predicted value for five consecutive days, indicating that the trend of change exceeds the normal pattern. Comparing the trend of Y1 with other main grounding down conductors Y2 and Y3, the average daily change rate of Y2 over the past 7 days is 0.21%, and that of Y3 is 0.25%, both within the normal range. The change rate of Y1 is 9.3 times that of Y2, a significant difference. The average daily change rates of the corresponding branch grounding down conductors Z1 and Z2 over the past 7 days are 0.28% and 0.31%, respectively, showing no abnormalities, ruling out problems with the overall grounding grid.

[0114] According to the trend hazard association table, the rapid abnormal upward trend of Y1 down conductor matches the preset hazard type of grounding down conductor and ground grid welding point detachment or loosening. Combined with the characteristics of the oil depot environment, it is determined that the cause of the hazard may be that long-term vibration generated by the operation of oil depot equipment has caused the welding point of Y1 down conductor and ground grid to crack, and the contact resistance continues to increase.

[0115] The intelligent control platform generates a trend analysis report for the Y1 down conductor and pushes it to the display module. This report includes a trend chart showing the resistance change curve over the past 90 days and a bar chart comparing the daily average change rate over the past 7 days. Key data points include a baseline value of 0.85Ω, a real-time value of 1.12Ω, a 7-day daily average change rate of 1.95%, and an excess of 0.07Ω over the predicted value. A potential hazard is loosening / detachment at the welding point between the Y1 down conductor and the grounding grid, classified as high risk.

[0116] The Y1 downline trend analysis report marks the Y1 downline monitoring points in red on the 3D visualization interface, pushes emergency warning information to the mobile APP and computer client of oil depot operation and maintenance management personnel, and simultaneously sends the trend analysis report.

[0117] Based on the analysis results, the intelligent control platform output emergency alarms and targeted handling instructions, clearly prioritizing the handling as Level 1, focusing the investigation on the welded connection between the Y1 down conductor and the grounding grid. Maintenance personnel arrived on-site within 2 hours of receiving the instruction and inspected the welded point between the Y1 down conductor and the grounding grid using specialized equipment. They discovered a crack of approximately 3mm caused by long-term vibration and immediately re-welded and reinforced it. After the handling was completed, the platform continuously strengthened monitoring, adjusting the monitoring frequency of the Y1 down conductor to once every 5 minutes. Over the following 24 hours, the resistance value stabilized between 0.83Ω and 0.87Ω, returning to near the baseline value, with the rate of change decreasing to 0.12%, verifying that the potential hazard had been successfully eliminated.

[0118] This invention discloses an explosion-proof online monitoring system and device for grounding resistance. Firstly, it employs an integrated explosion-proof design with an IP67 protection rating, enabling safe and stable operation in flammable, explosive, and harsh environments, thus broadening the applicable scenarios for grounding resistance monitoring. Secondly, it utilizes a non-contact loop measurement method with a through-hole ground wire installation, ensuring uninterrupted operation of the grounding system. This results in short measurement times, high accuracy, and high efficiency, enabling real-time monitoring of grounding resistance. Thirdly, it supports multi-dimensional monitoring and multi-mode communication, collecting data on resistance parameters, connection status, anti-theft status, and battery status. Data is remotely transmitted via LoRa, Ethernet, and 4G, accommodating both local data management and remote monitoring needs. Finally, the accompanying monitoring system constructs a full-chain intelligent management and control process. Through big data analysis and intelligent decision-making, it achieves accurate identification, timely early warning, and rapid response to potential grounding system hazards, promoting a shift from passive to proactive lightning protection and enhancing the systematization, refinement, and scientific level of lightning protection and disaster reduction work.

[0119] In summary, the explosion-proof grounding resistance online monitoring system and device of this invention creates a comprehensive digital lightning safety protection solution covering the entire chain of perception, transmission, analysis, decision-making, and disposal. It enables the normalization of grounding system monitoring, promotes the transformation and upgrading of traditional lightning protection grounding system monitoring mode towards digitalization, networking, and intelligence, enhances the systematization, refinement, and scientification of lightning protection and disaster reduction work, and realizes the transformation from passive protection to active defense in lightning protection.

[0120] The above description illustrates preferred embodiments of the present invention and helps those skilled in the art to more fully understand the technical solution of the present invention. However, these embodiments are merely illustrative and should not be construed as limiting the specific implementation of the present invention to these embodiments. For those skilled in the art, several simple deductions and modifications can be made without departing from the inventive concept, and all such modifications should be considered within the protection scope of the present invention.

Claims

1. An on-line monitoring system of an explosion-proof grounding resistance, comprising a metal grounding electrode, a connecting conductor and a grounding loop formed by a device to be protected, characterized in that, Also include resistance monitoring device and intelligent control platform; The resistance monitoring device is integrated with a mutual inductor and a control module; the control module sends an excitation pulse signal instruction to the mutual inductor, receives a pulse potential E and a loop current I generated by the grounding loop, and calculates a real-time resistance value of the loop by R=E / I, thereby monitoring the resistance fluctuation state in unit time in all dimensions online; The intelligent control platform communicates with the resistance monitoring device through a local area network, and transmits the real-time resistance value of the grounding loop to the intelligent control platform for monitoring and display.

2. The on-line monitoring system for the anti-explosion grounding resistor according to claim 1, characterized in that, The equipment to be protected includes an oil tank body and a transformer substation.

3. The on-line monitoring system for the anti-explosion grounding resistor according to claim 2, characterized in that, The oil tank body is provided with at least one grounding electrode, which is connected with a metal shell of the oil tank body and the resistance monitoring device through a connecting conductor to form a grounding loop.

4. The on-line monitoring system for the anti-explosion grounding resistor according to claim 1, characterized in that, The resistance monitoring device body is provided with a ground wire through hole, and the ground wire passes through the ground wire through hole during installation, is connected in series into the grounding loop, and the connection state of the downlead, the loop grounding resistance and the metal loop connection resistance are measured and monitored by using the loop method.

5. The on-line monitoring system for the anti-explosion grounding resistor according to claim 1, characterized in that, The resistance monitoring device is provided with an LCD display screen, and is further integrated with a separate battery module and a multi-element communication module; the separate battery module supports separate replacement, provides power supply for the resistance monitoring device, and ensures normal work; The multi-element communication module uploads the resistance value, grounding state information and equipment battery voltage data processed by the control module to the intelligent control platform, and realizes remote data transmission.

6. The on-line monitoring system for the anti-explosion grounding resistor according to claim 5, characterized in that, The multi-element communication module communicates with the intelligent control platform through LoRa, and also supports Ethernet, 4G and Tcp / WiFi communication modes through an expansion module.

7. The on-line monitoring system for the anti-explosion grounding resistor according to claim 1, characterized in that, The intelligent control platform includes a data receiving module, a data processing module, a display module and a decision alarm module; the data receiving module realizes stable reception of multi-source data; The data processing module performs deep processing on data through an algorithm model; The display module provides an intuitive operation interface and a data display carrier for users; The decision alarm module intelligently analyzes and judges based on analysis results and generates action instructions.

8. The on-line monitoring system for the anti-explosion grounding resistor according to claim 7, characterized in that, The data processing module first performs data cleaning on data, and performs calculation processing, trend analysis and abnormality identification on all cleaned data; The trend analysis captures the change rule of the grounding resistance through multi-dimensional comparison of historical data and real-time data, generates a trend hidden danger correlation table, and identifies potential hidden dangers in advance; The abnormality identification identifies abnormal data according to a preset threshold, generates a trend analysis report according to the abnormal data, pushes the trend analysis report to the decision alarm module, and triggers an alarm prompt.

9. The on-line monitoring system for an explosion-proof grounding resistor according to claim 8, characterized in that, The data processing module is also integrated with a multi-monitoring-point correlation analysis submodule, including homologous comparison, time sequence tracing and path generation; by comparing the resistance change trend, connection resistance difference and abnormal occurrence time sequence of multiple monitoring points in the same grounding system, the fault root location of the grounding system is automatically located, and a targeted troubleshooting path is generated.

10. The on-line monitoring system for the anti-explosion grounding resistor according to claim 1, characterized in that, The smart control platform allocates memory for real-time data stream by using chunked reference counting pool. The underlying system divides the real-time resistance data received by the application layer system into fixed chunks according to the integer multiple of the input or output buffer, binds an initial reference count for each chunk, increases the reference count by 1 when the chunk is referenced, decreases the reference count by 1 after the chunk is processed, and recycles the chunk for reuse when the reference count drops to 0, while invalidating the data; The underlying system uses a double-ended stack allocator to integrate the chunk pool and historical data management. The bottom stack stores historical data, including the baseline of the trend hazard correlation table and the long-term reference value of the monitoring point. The top stack stores real-time data. After each round of comparison between historical data and real-time data is completed, the top stack is released to a preset flag bit.

11. The on-line monitoring system for an explosion-proof grounding resistor according to claim 1, characterized in that, The resistance monitoring device further comprises a sensing unit, a triggering unit, and a compensation execution unit. The sensing unit senses environmental parameters of the monitoring environment and sends a resistance switching trigger signal when the environmental parameters detected by the sensing unit exceed a preset threshold. The triggering unit receives the resistance switching trigger signal and converts it into a mechanical displacement to be transmitted to the compensation execution unit. The compensation execution unit dynamically corrects the ground resistance measurement value.

12. An on-line monitoring device for an explosion-proof grounding resistance, characterized in that, The application relates to an explosion-proof ground resistance online monitoring system. The application relates to an explosion-proof ground resistance online monitoring system.

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