Resistive current recording and monitoring device for lightning arrester valve plate

Abstract

The invention discloses a lightning arrester valve plate resistive current recording monitoring device, which belongs to the technical field of lightning arrester resistive current monitoring, and comprises a resistive matching unit, an energy taking resistor and a signal acquisition unit, the resistive matching unit comprises an equivalent resistor and a deploying capacitor; the equivalent resistor is connected in parallel with the deploying capacitor; the equivalent resistor is matched with parameters of a lightning arrester valve plate, and dynamic adjustment is carried out through a deploying capacitor, so that impedance matching is realized; the equivalent resistor and the energy taking resistor are connected in series with the lightning arrester; and the equivalent resistor and the energy taking resistor are connected with the signal acquisition unit to realize resistive current recording monitoring. The technical problem that the resistive current monitoring result is inaccurate due to environmental factors, bus fluctuation and lightning stroke interference is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of resistive current of lightning arresters, and relates to a device for recording and monitoring the resistive current of lightning arrester discs. Background Art

[0002] In the power system, the stable operation of the power grid is crucial for ensuring the continuity and reliability of power supply. However, lightning activity, as a natural phenomenon, poses a serious threat to the power grid. When lightning strikes directly or is induced on the power grid lines, huge overvoltages and overcurrents will be generated. If this energy cannot be effectively discharged, it will damage the equipment in the power grid and even cause large-scale power outages. Therefore, lightning protection has become an important link in power grid safety.

[0003] As the main lightning protection equipment in the power grid, the performance of the lightning arrester is directly related to the lightning protection effect of the power grid. The lightning arrester protects the power grid equipment from lightning damage by absorbing and discharging lightning energy. However, with the increase of service time and the influence of environmental factors, the performance of the lightning arrester will gradually decline, resulting in the weakening of its protection function. When the performance of the lightning arrester deteriorates, overvoltage is likely to occur during lightning strikes, which will bring great harm to other equipment in the power grid.

[0004] In order to effectively monitor the performance of the lightning arrester, the resistive current has become an important reference index. The resistive current can reflect the resistance characteristics inside the lightning arrester, and thus indirectly reflect its overall performance. Therefore, through the perception detection of the resistive current, the abnormality of the lightning arrester performance can be detected in time, providing an important basis for the maintenance and replacement of the equipment.

[0005] At present, there are mainly two detection methods for resistive current: one is the on-site detection method of resistive current based on the grounding current of capacitive equipment. This method uses the equipment grounding current as a reference signal and realizes the perception of the resistive current by calculating the voltage phase difference during the operation of the lightning arrester; the other is the detection method based on composite criteria. In a small current grounding system, this method fully considers the characteristics of its early faults and realizes current perception by comprehensively analyzing various signal characteristics.

[0006] However, in practical applications, the perception detection of resistive current faces many challenges. First, various interference factors such as external temperature, humidity, and electromagnetic field will affect the total leakage current and resistive current of the lightning arrester, resulting in deviation of the detection results. Second, with the fluctuation of the bus voltage, the resistive current of the lightning arrester will also change accordingly, which increases the complexity of the detection. In addition, the existing perception methods are easily affected by instantaneous lightning interference signals, resulting in inaccurate resistive current perception results. Summary of the Invention

[0007] The object of the present invention is to solve the technical problem that the monitoring results of resistive current are inaccurate due to environmental factors, busbar fluctuations and lightning strike interference in the prior art, and to provide a resistive current recording and monitoring device for arrester valve plates.

[0008] To achieve the above object, the present invention adopts the following technical solutions: The present invention discloses a resistive current recording and monitoring device for arrester valve plates, including a resistive matching unit, a power-taking resistor and a signal acquisition unit; The resistive matching unit includes an equivalent resistor and a tuning capacitor; the equivalent resistor is connected in parallel with the tuning capacitor; the equivalent resistor is parameter-matched with the arrester valve plate and is dynamically adjusted through the tuning capacitor to achieve impedance matching; The equivalent resistor and the power-taking resistor are connected in series with the arrester; Both the equivalent resistor and the power-taking resistor are connected to the signal acquisition unit to realize resistive current recording and monitoring.

[0009] Further, the signal acquisition unit includes a voltage-dividing resistor, an isolation operational amplifier and a current transformer; the voltage-dividing resistor is connected in parallel with the equivalent resistor, and the isolation operational amplifier is connected in parallel with the voltage-dividing resistor; the current transformer is connected across the power-taking resistor.

[0010] Further, the current transformer is a dual-secondary current transformer.

[0011] Further, the isolation operational amplifier is connected to an A / D converter.

[0012] Further, the primary side of the current transformer is connected in parallel with the power-taking resistor, the current transformer includes two secondary sides, one of the secondary sides is connected to a recording resistor, and the other secondary side is connected to a power management unit.

[0013] Further, the power management unit is connected to a wireless communication unit.

[0014] Further, the wireless communication unit is connected to a core processing unit.

[0015] Further, the recording resistor is connected to an A / D converter.

[0016] Further, the A / D converter is connected to a core processing unit.

[0017] Further, the power management unit is connected to a core processing unit.

[0018] Compared with the prior art, the present invention has the following beneficial effects: The present invention discloses a resistive current oscillogram monitoring device for arrester valve discs. In this device, the resistive matching unit realizes the precise matching of arrester valve disc parameters through the parallel design of an equivalent resistor and a tuning capacitor. At the same time, by utilizing the dynamic adjustment function of the tuning capacitor, the impedance value can be adjusted in real time according to the changes in the actual working environment, ensuring the best impedance matching state throughout the monitoring process. This not only improves the accuracy of the monitoring data but also effectively reduces the energy loss during the monitoring process. The equivalent resistor and the energy-taking resistor are connected in series to the arrester working circuit, and energy can be directly obtained from the current leaked by the arrester. This design not only simplifies the energy acquisition process but also improves the energy utilization efficiency. The energy-taking resistor converts the leaked current into a voltage signal, providing a stable energy source for subsequent signal acquisition and processing. The signal acquisition unit is connected to the equivalent resistor and the energy-taking resistor and can collect the resistive current signal of the arrester valve disc in real time. Through advanced signal processing techniques, operations such as filtering, amplifying, and digitizing the collected signal can be performed to obtain clear and accurate resistive current waveform data. These data are of great significance for analyzing the working state of the arrester and predicting potential faults. The device can monitor the resistive current waveform of the arrester valve disc in real time and analyze the monitoring data through a built-in early warning algorithm. Once an abnormal waveform or a current value exceeding the preset threshold is detected, the device will immediately issue an early warning signal to remind the operation and maintenance personnel to take measures in a timely manner. This helps to avoid power system accidents caused by the long-term overload or failure of the arrester.

[0019] Furthermore, the design of the voltage-dividing resistor in parallel with the equivalent resistor enables the voltage-dividing resistor to accurately obtain the voltage signal generated by the resistive current from the equivalent resistor. This voltage-dividing method not only simplifies the signal acquisition circuit but also improves the accuracy and stability of signal acquisition. The voltage signal after voltage division is further amplified and processed by the isolation operational amplifier, providing a high-quality analog signal source for subsequent digital processing. The use of the isolation operational amplifier realizes high-isolation transmission between the signal acquisition unit and the main circuit. This can not only effectively prevent the high voltage and large current in the main circuit from interfering with or damaging the signal acquisition unit but also improve the safety and reliability of signal acquisition. At the same time, the isolation operational amplifier also has excellent linearity and gain stability, ensuring that the acquired signal is transmitted to the subsequent processing unit without distortion. The current transformer is connected across the energy-taking resistor and can convert the current signal on the energy-taking resistor into a voltage signal for measurement. This conversion method not only improves the accuracy and range of current measurement but also simplifies the design of the current measurement circuit. The current transformer has high precision, high stability, and good linearity, ensuring that the measured current signal accurately reflects the actual working state of the arrester valve disc. The combined use of the voltage-dividing resistor, isolation operational amplifier, and current transformer makes the signal acquisition unit have stronger anti-interference ability. Whether it is electromagnetic interference from the main circuit or noise interference in the external environment, it can be effectively suppressed and eliminated. This ensures that the acquired signal has a high degree of authenticity and credibility, providing a reliable basis for subsequent data analysis and processing.

[0020] Furthermore, the dual-secondary design enables the current transformer to simultaneously meet the requirements of current measurement and energy supply, improving the functionality and flexibility of the device; by optimizing the turns ratio of the secondary side, the current on the energy-taking resistor can be accurately measured.

[0021] Furthermore, through the built-in power management unit, the limited energy captured from the energy-taking resistor is effectively stored and reasonably distributed, aiming to maximize the energy utilization efficiency. In addition, all functional module chips in the system adopt a high-precision and low-power design scheme, ensuring high-precision measurement performance while maintaining low power consumption, thus achieving dual optimization of energy efficiency and measurement accuracy. Brief Description of the Drawings

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0023] Figure 1 Structural diagram of the arrester valve disc resistive current recording and monitoring device of the present invention. Detailed implementation mode

[0024] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Components of the embodiments of the present invention generally described and labeled in the accompanying drawings here can be arranged and designed in a variety of different configurations.

[0025] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0026] It should be noted that: like reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0027] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper", "lower", "horizontal", "inner", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, or the orientations or positional relationships in which the inventive product is customarily placed during use, it is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention. In addition, terms such as "first", "second", etc. are only used for descriptive distinction and should not be construed as indicating or implying relative importance.

[0028] In addition, if the term "horizontal" appears, it does not mean that the component is required to be absolutely horizontal, but it can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but it can be slightly inclined.

[0029] In the description of the embodiments of the present invention, it should also be noted that unless otherwise clearly specified and limited, if terms such as "set", "installed", "connected", "connected" are understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] The present invention will be further described in detail below with reference to the accompanying drawings: Refer to Figure 1 , the present invention provides a resistive current oscillogram monitoring device for a lightning arrester valve disc, including an equivalent resistor, a matching capacitor, an energy-taking resistor, an isolation operational amplifier, an isolation power supply, a mutual inductor, a power management unit, a recording resistor, a wireless communication unit, a core processing unit, and an A / D converter; The equivalent resistor is connected in parallel with the matching capacitor; the equivalent resistor reflects the current resistive current by selecting an equivalent resistor with impedance matching through consulting and measuring the impedance parameters of the lightning arrester valve disc. Since the lightning arrester valve disc has a certain capacitance, the capacitance value of the matching capacitor is adjusted to achieve complete impedance matching of the lightning arrester valve disc. The equivalent resistor and the energy-taking resistor are connected in series with the lightning arrester; the energy-taking resistor is connected in series in the working circuit of the lightning arrester to convert the leakage current of the lightning arrester into voltage; the general circuit of the lightning arrester is connected to the high-voltage end at one end and grounded at the other end. The equivalent resistor and the energy-taking resistor are both connected to the signal acquisition unit to realize resistive current oscillogram monitoring. The voltage-dividing resistor is connected in parallel with the equivalent resistor, and the isolation operational amplifier is connected in parallel with the voltage-dividing resistor; the isolation operational amplifier performs isolation operation and amplification on the voltage signals at both ends of the resistor, and pre-processes the signals and then sends them to the A / D conversion module. The isolation operational amplifier is connected to the isolation power supply, and the isolation power supply uses an external isolation power supply to supply power to the isolation operational amplifier module. Due to isolation requirements, different isolation power supplies are required to supply power to the input end and the output end of the isolation operational amplifier module respectively.

[0031] The mutual inductor is connected across the energy-taking resistor. The mutual inductor is a double-secondary current mutual inductor. The voltage of the energy-taking resistor is proportionally amplified by the mutual inductor. The mutual inductor adopts a double-winding design, and the two secondaries have different turns ratios, respectively undertaking the functions of energy-taking and recording. The primary side of the mutual inductor is connected in parallel with the energy-taking resistor. The mutual inductor includes two secondaries, one of which is connected to a recording resistor, and the other is connected to a power management unit. The power management unit is connected to a wireless communication unit. The wireless communication unit is connected to a core processing unit. The recording resistor is connected to an A / D converter; the recording resistor converts the current signal generated by the secondary side of the mutual inductor into a voltage signal through the recording resistor and transmits it to the subsequent A / D conversion module for processing. Similarly, the isolation operational amplifier is also connected to an A / D converter, and both A / D converters are connected to the core processing unit.

[0032] The power management unit is connected to the core processing unit. The power management unit stores the electric energy amplified by the secondary side of the mutual inductor, supplies power for the operation of other modules, and manages and controls the energy distribution and flow at the same time. The core processing unit analyzes and processes the received resistive current value and waveform data, outputs the processing result, and realizes feedback on the control signal of the upper computer at the same time.

[0033] The resistive current oscillogram monitoring device for the lightning arrester valve disc of the present invention realizes precise matching with the parameters of the lightning arrester valve disc through the parallel design of the equivalent resistance and the tuning capacitor in the resistive matching unit, and can be dynamically adjusted through the tuning capacitor, effectively improving the flexibility and accuracy of impedance matching, thereby ensuring the authenticity and reliability of the monitoring data. The signal acquisition unit integrates a voltage-dividing resistor, an isolation operational amplifier, and a mutual inductor. In particular, a dual-secondary current mutual inductor is used to accurately acquire the resistive current signal, and the design of the isolation operational amplifier enhances the anti-interference ability of the signal. This design enables the device to operate stably in a complex electromagnetic environment and accurately reflect the working state of the lightning arrester. One secondary side of the mutual inductor is connected to a recording resistor for signal recording, and the other secondary side is connected to the power management unit, which not only realizes the dual utilization of the signal but also effectively manages the energy through the power management unit to provide a stable and reliable power supply for the entire monitoring device. This design improves the energy utilization efficiency and enhances the autonomous operation ability of the device. The integration of the wireless communication unit and the core processing unit enables the monitoring data to be uploaded to the remote monitoring center in real time, realizing remote real-time monitoring and data analysis of the lightning arrester status. This not only improves the operation and maintenance efficiency but also reduces the cost and risk of manual inspection. The application of the A / D converter converts the analog signal into a high-precision digital signal, providing a solid foundation for the subsequent processing and analysis of the data. This helps to analyze the performance changes of the lightning arrester more precisely, detect potential faults in a timely manner, and improve the safety and stability of the power system. Various factors in practical applications, such as impedance matching, signal interference, and energy management, are considered to ensure the overall reliability and stability of the system. At the same time, through the intelligent and remote monitoring method, the operation and maintenance process are simplified, and the usability and maintenance efficiency of the equipment are improved.

[0034] The working process / working principle of the present invention is as follows: First, by consulting and measuring the impedance parameters of the arrester valve disc, an equivalent resistor with impedance matching is selected. At the same time, the capacitance value of the tuning capacitor is adjusted to achieve impedance matching of the arrester in cooperation with the equivalent resistor. When the resistive current is generated in the arrester valve disc, the signal is transmitted to the isolation operational amplifier module through the equivalent resistor circuit, amplified by operation and then sent to the A / D conversion module for analog-to-digital conversion. Finally, the digital signal is sent to the core processing unit for processing. The isolation operational amplifier needs to be powered separately from both sides during operation. When the leakage current is generated in the arrester, the energy-taking resistor connected in series in the circuit and the double-winding current transformer amplify the leakage current. One secondary side delivers the amplified energy to the power management module, and the power management module manages and distributes the energy to supply power to other various power-consuming modules. The other secondary side inputs the leakage current signal into the A / D conversion module through the recording resistor. After analog-to-digital conversion, the current data information is sent into the core processing unit. The core processing unit processes the received resistive current data and current waveform data and sends them to the host through the wireless communication module to complete the monitoring of the resistive current.

[0035] An embodiment of the present invention is based on the above-mentioned arrester valve disc resistive current recording and monitoring device, and the implementation steps are as follows: Consult the valve disc parameters of the zinc oxide arrester working on a 110 kV substation and select a matching equivalent resistor value. Use an adjustable high-voltage capacitor as the tuning capacitor, and by adjusting its capacitance value, achieve complete impedance matching with the arrester valve disc. The energy-taking resistor is connected in series in the arrester working circuit to convert the arrester leakage current into a voltage signal.

[0036] Select a high withstand voltage level for the isolation operational amplifier, connect it in parallel across the voltage-dividing resistor, and perform isolation operation and amplification on the voltage signal across the resistor. The isolation operational amplifier is powered by isolated 220V mains power.

[0037] Adopt a double-secondary current transformer, connect it across the energy-taking resistor. The primary side of the transformer is connected in parallel with the energy-taking resistor, and the two secondary sides adopt different turns ratios: one secondary side has a turns ratio of 1:10 for energy taking; the other secondary side has a turns ratio of 1:2.5 for recording waves.

[0038] The power management unit is connected to one secondary side of the transformer, used to store the electrical energy amplified by the secondary side of the transformer and supply power to other modules. The wireless communication unit adopts the LoRa communication protocol and is connected to the core processing unit for data transmission.

[0039] The recording resistor is connected to the other secondary side of the transformer to convert the current signal into a voltage signal. Select a 16-bit multi-channel chip for the A / D converter to perform analog-to-digital conversion on the voltage signals output by the isolation operational amplifier and the recording resistor. The core processing unit adopts a 32-bit single-chip microcomputer chip, receives the digital signal output by the A / D converter, performs analysis and processing, and outputs the processing result to the wireless communication unit.

[0040] The above-mentioned devices are integrated into a lightning arrester monitoring device, which can realize the real-time acquisition and monitoring of the leakage current and resistive current waveforms during the operation of the lightning arrester and wirelessly transmit data, and can monitor the operation status of the lightning arrester in real time to ensure the safety of the line.

[0041] During installation, the monitoring device is installed in series between the zinc oxide lightning arrester and the grounding terminal, and adjusted and configured according to the parameters of the selected equivalent resistance and matching capacitor. Start the monitoring device and check the working status of each module. Set parameters for the core processing unit through the host computer, including sampling frequency, data transmission rate, etc. The monitoring device starts to collect the leakage current and resistive current waveform data of the lightning arrester in real time. The core processing unit processes the collected data and transmits the data to the host computer through the wireless communication unit.

[0042] In the resistive matching unit of the device of the present invention, through the parallel structure of the equivalent resistance and the matching capacitor and the precise matching with the parameters of the lightning arrester valve disc, the error during the monitoring process is effectively reduced. At the same time, the dynamic adjustment function of the matching capacitor further ensures the accuracy of impedance matching and improves the reliability of the monitoring data. The series design of the equivalent resistance and the energy-taking resistance enables the device to directly obtain energy from the working circuit of the lightning arrester and convert it into a voltage signal that can be used for monitoring. The voltage-dividing resistor, isolation operational amplifier, and mutual inductor in the signal acquisition unit jointly achieve the precise acquisition and amplification of the resistive current signal, providing a solid foundation for subsequent data processing. The use of a dual-secondary current transformer not only realizes the proportional amplification of the voltage signal of the energy-taking resistance, but also undertakes the functions of energy-taking and waveform recording respectively through different turns ratio designs of the two secondaries, improving the functionality and flexibility of the device. The analog signal is converted into a digital signal through an A / D converter and sent to the core processing unit for processing, realizing the digitization and intelligence of the monitoring data. At the same time, the connection of the wireless communication unit enables the device to transmit the monitoring data to the remote monitoring center in real time, facilitating the timely discovery and handling of abnormal conditions of the lightning arrester. The design of the power management unit not only realizes the storage and utilization of the amplified electric energy on the secondary side of the mutual inductor, but also provides a stable power supply for other modules. At the same time, through the management and control of the energy distribution and flow, the stable operation of the device in a complex environment is ensured. The design of the entire device fully considers the actual needs of monitoring the resistive current of the lightning arrester valve disc. Through precise impedance matching, efficient signal acquisition, digital data processing, and wireless communication methods, the monitoring efficiency and accuracy are significantly improved. Real-time monitoring of the operation status of the lightning arrester, timely discovery and handling of potential fault hazards, are of great significance for ensuring the safe and stable operation of the power system. The monitoring device of the present invention provides strong support for the safety maintenance of the power system by providing accurate and reliable monitoring data.

[0043] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A resistive current oscillogram monitoring device for an arrester valve plate, characterized in that, It includes a resistive matching unit, an energy-taking resistor, and a signal acquisition unit; The resistive matching unit includes an equivalent resistor and a tuning capacitor; the equivalent resistor is connected in parallel with the tuning capacitor; the equivalent resistor is parameter-matched with the arrester valve disc and is dynamically adjusted through the tuning capacitor to achieve impedance matching; The equivalent resistor and the energy-taking resistor are connected in series with the arrester; Both the equivalent resistor and the energy-taking resistor are connected to the signal acquisition unit to realize resistive current oscillogram monitoring.

2. The resistive current oscillogram monitoring device for arrester valve plates according to claim 1, characterized in that The signal acquisition unit includes a voltage-dividing resistor, an isolation operational amplifier, and a mutual inductor; the voltage-dividing resistor is connected in parallel with the equivalent resistor, and the isolation operational amplifier is connected in parallel with the voltage-dividing resistor; the mutual inductor is connected across the two ends of the energy-taking resistor.

3. The resistive current oscillogram monitoring device for arrester valve plates according to claim 2, characterized in that, The mutual inductor is a dual-secondary current mutual inductor.

4. The resistive current oscillogram monitoring device for arrester valve pieces according to claim 3, characterized in that, The isolation operational amplifier is connected to an A / D converter.

5. The resistive current oscillogram monitoring device for arrester valve pieces according to claim 3, characterized in that, The primary side of the mutual inductor is connected in parallel with the energy-taking resistor. The mutual inductor includes two secondary sides. One secondary side is connected to a recording resistor, and the other secondary side is connected to a power management unit.

6. The resistive current oscillogram monitoring device for arrester valve plate according to claim 5, wherein The power management unit is connected to a wireless communication unit.

7. The resistive current oscillogram monitoring device for arrester valve plates according to claim 5, characterized in that The wireless communication unit is connected to a core processing unit.

8. The resistive current oscillogram monitoring device for arrester varistor according to claim 5, wherein, The recording resistor is connected to an A / D converter.

9. The resistive current oscillogram monitoring device for arrester valve plates according to claim 4 or 8, characterized in that, The A / D converter is connected to a core processing unit.

10. The resistive current oscillogram monitoring device for arrester varistor according to claim 5, characterized in that, The power management unit is connected to a core processing unit.

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