Discharge indicator and discharge detection method
By integrating a high-frequency current sensor with a three-color meter, a magnetic coil, and a circuit board, low-power, low-volume discharge detection is achieved, solving the problems of high power consumption, large size, and difficulty in long-term monitoring of traditional devices, thus improving detection efficiency and accuracy.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- 国网信息通信产业集团有限公司北京分公司
- Filing Date
- 2025-12-23
- Publication Date
- 2026-05-29
AI Technical Summary
Traditional discharge detection devices have high power consumption and large size, making it difficult to achieve long-term continuous monitoring, resulting in low discharge detection efficiency.
A high-frequency current sensor is directly electrically connected to a three-color meter. It integrates a magnetic coil and a circuit board, and collects the original current signal of the grounding wire of high-voltage equipment through electromagnetic induction. The sensor performs signal processing and voltage conversion inside, and uses a three-color meter for visual hierarchical display.
It achieves long-term continuous monitoring with low power consumption and small size, can detect power-on in real time, has high signal accuracy, significantly improves detection efficiency, and makes it easy for maintenance personnel to quickly judge the status of equipment.
Smart Images
Figure CN122109738A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of power detection technology, and in particular to a discharge indicator and a discharge detection method. Background Technology
[0002] With the rapid development of power systems, high-voltage equipment such as transformers and cables, as core infrastructure ensuring stable power transmission and supply, directly affect the safety, reliability, and economy of the entire power system. However, during long-term service, these high-voltage devices are subjected to the combined effects of multiple factors, including electric fields, temperature, humidity, mechanical stress, and environmental corrosion, causing the internal insulation materials to gradually age and deteriorate, leading to partial discharge. Partial discharge is a significant indicator of insulation degradation in high-voltage equipment, and the resulting electrical, thermal, mechanical stress, and chemical corrosion further exacerbate insulation damage. Therefore, to ensure the safe and stable operation of the power system and avoid impacts on industrial production, social life, and public safety, effective monitoring of the partial discharge status of high-voltage equipment is crucial.
[0003] Currently, traditional discharge detection devices use independent general-purpose detection equipment and large processing equipment to detect the discharge status of high-voltage equipment. However, these devices have high power consumption, large size, and are difficult to monitor the discharge status of equipment for a long time, resulting in low discharge detection efficiency. Summary of the Invention
[0004] The purpose of this application is to provide a discharge indicator and a discharge detection method to solve the technical problems of high power consumption, large size, and difficulty in long-term continuous monitoring of the discharge state of equipment in traditional devices, resulting in low discharge detection efficiency.
[0005] To achieve the above objectives, this application provides the following solution: In a first aspect, this application provides a discharge indicator, which includes: A high-frequency current sensor and a three-color meter electrically connected to the high-frequency current sensor are provided. The high-frequency current sensor is installed on the grounding wire of the high-voltage equipment. The high-frequency current sensor has a circuit board and a magnetic coil electrically connected to the circuit board inside. A signal processing module is integrated on the circuit board. The magnetic coil is used to: collect the original current signal of the grounding wire of the high-voltage equipment by electromagnetic induction and transmit it to the signal processing module; The signal processing module is used to: extract and convert the original current signal to obtain the target voltage signal and transmit it to the three-color meter; The three-color meter is used to: receive and respond to the target voltage signal, drive the pointer in the dial to perform a rotation operation, so as to visually and hierarchically display the partial discharge status of the high-voltage equipment.
[0006] Optionally, the signal processing module includes: a high-frequency current extraction circuit and a meter driving circuit; the high-frequency current extraction circuit is electrically connected to the magnetic coil and the meter driving circuit respectively; the meter driving circuit is also electrically connected to the three-color meter. The high-frequency current extraction circuit is used to: filter interference signals in the original current signal and amplify them to obtain the target current signal and transmit it to the meter drive circuit; when the high-voltage equipment has partial discharge, the target current signal includes a high-frequency discharge signal, which refers to a current signal released by the high-voltage equipment through partial discharge and whose signal frequency is not lower than a preset threshold; the interference signal is a current signal whose signal frequency is lower than the preset threshold. The meter driving circuit is used to: perform voltage conversion processing on the target current signal to obtain the corresponding target voltage signal and transmit it to the three-color meter.
[0007] Optionally, the meter drive circuit is specifically used for: The target current signal is graded to obtain graded current signals; and according to a preset current-to-voltage conversion relationship, the graded current signals are subjected to voltage conversion processing to generate corresponding target voltage signals; or... According to the preset current-voltage conversion relationship, the target current signal is subjected to voltage conversion processing to obtain an intermediate voltage signal, and the intermediate voltage signal is graded and judged to generate a target voltage signal corresponding to the graded judgment result; the target voltage signal includes a first voltage signal, a second voltage signal and a third voltage signal.
[0008] Optionally, the dial is provided with a first color display area, a second color display area, and a third color display area that are sequentially connected according to an angle; the three-color meter is specifically used for: When the target voltage signal is the first voltage signal, the pointer is driven to rotate to the first color display area, which is used to indicate that the high voltage equipment is in a normal state. When the target voltage signal is the second voltage signal, the pointer is driven to rotate to the second color display area, which is used to indicate that the high-voltage equipment is in a warning state. When the target voltage signal is the third voltage signal, the pointer is driven to rotate to the third color display area, which is used to indicate that the high-voltage equipment is in a fault state; the amplitude of the first voltage signal is less than the amplitude of the second voltage signal, and the amplitude of the second voltage signal is less than the amplitude of the third voltage signal.
[0009] Optionally, the angle range of the first color display area is greater than the angle range of the third color display area, and the angle range of the third color display area is greater than the angle range of the second color display area.
[0010] Optionally, the high-frequency current sensor further includes a shielding housing, and the magnetic coil and the circuit board are mounted inside the shielding housing; The shielding housing is used to shield the high-frequency current sensor from external electromagnetic interference.
[0011] Optionally, the shielding shell also includes a battery compartment, in which a power supply module is installed. The power supply module is electrically connected to the circuit board. The power supply module is used to supply power to the signal processing module on the circuit board.
[0012] Optionally, the signal bandwidth of the high-frequency current sensor is 500kHz to 20MHz.
[0013] Optionally, the circuit board also integrates a protection circuit, which is electrically connected to the high-frequency current extraction circuit and the meter drive circuit respectively. The protection circuit is used to provide coordinated protection for the high-frequency current extraction circuit and the meter drive circuit.
[0014] Secondly, this application provides a vehicle discharge detection method, which is applied to the discharge indicator provided in the above embodiments. The method includes: The original current signal of the grounding wire of the high-voltage equipment is acquired by electromagnetic induction using a magnetic coil and transmitted to the signal processing module. The signal processing module extracts and converts the original current signal to obtain the target voltage signal, which is then transmitted to the three-color meter. The tri-color meter receives and responds to the target voltage signal, driving the pointer in the dial to rotate, thereby visually and hierarchically displaying the partial discharge status of the high-voltage equipment.
[0015] According to the specific embodiments provided in this application, the following technical effects are disclosed: Compared with existing technologies, the discharge indicator in this solution directly connects a high-frequency current sensor to a three-color meter, and integrates a magnetic coil and circuit board within the sensor. This avoids the use of high-power components such as independent general-purpose detection devices found in traditional devices, significantly reducing overall power consumption and size while meeting the needs of long-term continuous monitoring. The magnetic coil non-invasively collects the original current signal of the high-voltage equipment's grounding wire based on the principle of electromagnetic induction, enabling real-time live detection without shutting down the equipment. This is convenient to operate and does not affect the normal operation of the equipment, allowing for long-term discharge status monitoring. Furthermore, the signal processing module is integrated inside the sensor, enabling signal extraction and voltage conversion of the original current signal without long-distance transmission, reducing signal loss and interference in the signal transmission process and ensuring signal accuracy and the highest detection precision. Finally, the rotation of the pointer in the three-color meter provides a visual, hierarchical display of the partial discharge status, allowing maintenance personnel to intuitively and quickly determine the status of the high-voltage equipment, significantly improving the efficiency of high-voltage equipment discharge status detection. Attached Figure Description
[0016] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 This is a schematic diagram of the structure of a discharge indicator according to one embodiment of this application; Figure 2 This is a schematic diagram of the structure of a discharge indicator provided in another embodiment of this application; Figure 3 This is a schematic diagram of the structure of a discharge indicator provided in another embodiment of this application; Figure 4 This is a schematic flowchart of a discharge detection and control method provided in an embodiment of this application.
[0018] Explanation of reference numerals in the attached figures: High-frequency current sensor-10, magnetic coil-11, circuit board-12, shielding housing-13, three-color meter-20, first color display area-21, second color display area-22, third color display area-23, signal processing module-120, high-frequency current extraction circuit-121, meter drive circuit-122. Detailed Implementation
[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0020] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.
[0021] High-voltage equipment status detection devices in related technologies use high-power components such as independent general-purpose detection equipment and large processing equipment (such as MCU). Each processing module adopts a split structure design, which not only results in high overall power consumption and large size, making it difficult to achieve long-term continuous monitoring of the equipment's discharge status, but also requires professional instruments to interpret the results, leading to problems such as high deployment difficulty, insufficient signal accuracy, and low discharge detection efficiency.
[0022] To address the aforementioned shortcomings, this application provides a discharge indicator. Compared to existing technologies, the discharge indicator in this solution directly connects a high-frequency current sensor to a three-color meter, and integrates a magnetic coil and circuit board within the sensor. This avoids the use of high-power components such as independent general-purpose detection devices found in traditional devices, significantly reducing overall power consumption and size while meeting the requirements for long-term continuous monitoring. The magnetic coil non-invasively collects the original current signal from the grounding wire of the high-voltage equipment based on the principle of electromagnetic induction, enabling real-time live detection without shutting down the equipment. This is convenient to operate and does not affect the normal operation of the equipment, allowing for long-term discharge status monitoring. Furthermore, the signal processing module is integrated inside the sensor, enabling signal extraction and voltage conversion of the original current signal without long-distance transmission, reducing signal transmission losses and interference, and ensuring signal accuracy and maximum detection precision. Finally, the rotation of the pointer in the three-color meter provides a visual, hierarchical display of the partial discharge status, facilitating maintenance personnel to intuitively and quickly determine the status of the high-voltage equipment, significantly improving monitoring efficiency and the timeliness of fault warnings.
[0023] Please see Figure 1 As shown, Figure 1 The diagram below shows the structure of a discharge indicator provided in this application. The discharge indicator includes a high-frequency current sensor 10 and a tri-color meter 20 electrically connected to the high-frequency current sensor 10. The high-frequency current sensor 10 is installed on the grounding wire of the high-voltage equipment. The high-frequency current sensor 10 has a circuit board 12 and a magnetic coil 11 electrically connected to the circuit board 12 inside it. A signal processing module 120 is integrated on the circuit board 12.
[0024] The magnetic coil 11 is used to: collect the original current signal of the grounding wire of the high-voltage equipment by electromagnetic induction and transmit it to the signal processing module 120; the signal processing module 120 is used to: extract the signal and convert the voltage of the original current signal to obtain the target voltage signal and transmit it to the three-color meter 20; the three-color meter 20 is used to: receive and respond to the target voltage signal, drive the pointer in the dial to perform rotation operation, so as to visually and hierarchically display the partial discharge status of the high-voltage equipment.
[0025] It should be noted that the aforementioned high-frequency current sensor (HFCT) is a current detection device designed based on the principle of electromagnetic induction, used to collect current signals generated by partial discharge in the grounding wire of high-voltage equipment. The HFCT contains a circuit board with an integrated signal processing module.
[0026] The aforementioned magnetic coil can be a ring structure, including a magnetic core and an induction coil. The magnetic core is made of a high-permeability nanocrystalline alloy to ensure efficient coupling to high-frequency electromagnetic fields. The induction coil is precisely wound to match the magnetic core, converting the magnetic field changes of the induced high-voltage equipment into a raw current signal output.
[0027] In the discharge indicator of this embodiment, the HFCT is directly installed on the grounding wire of the high-voltage equipment. It integrates a signal processing module, which can process the collected raw current signal into a target voltage signal and transmit it to the three-color meter. Compared with the traditional split detection scheme, it significantly shortens the signal transmission path and reduces interference. At the same time, with its miniaturized integrated design, it can adapt to the installation requirements of the narrow space around the high-voltage equipment, and achieve accurate and long-term capture of partial discharge signals.
[0028] Optionally, the aforementioned HFCT sensor can be fixed to the grounding wire of high-voltage equipment using a snap-on magnetic structure. This high-voltage equipment may include transformers, cable terminals, switchgear, etc. The sensor's induction coil is tightly coupled to the grounding wire, ensuring efficient capture of high-frequency current signals from the grounding wire through electromagnetic induction. The sensor's frequency band can be designed from 500kHz to 20MHz, fully covering the main high-frequency components of the partial discharge signal. Simultaneously, the magnetic coil and internal circuit board are integrated into a single package, significantly reducing electromagnetic interference from external cable connections and improving signal transmission stability. The magnetic coil output is directly connected to the signal processing module. The magnetic coil acquires the original current signal from the high-voltage equipment's grounding wire through electromagnetic induction and transmits it to the signal processing module. The signal processing module then extracts and converts the original current signal to obtain a voltage signal, which is transmitted to the three-color meter.
[0029] Please see Figure 2As shown, the aforementioned high-frequency current sensor also includes a shielding housing 13, within which the magnetic coil and circuit board are both installed. Figure 2 The magnetic coil and circuit board are not shown. The shielding housing 13 is used to shield the high-frequency current sensor from external electromagnetic interference.
[0030] The material of the aforementioned shielding shell needs to balance electromagnetic shielding performance, mechanical strength, and environmental adaptability. It can be a metal material, including copper, aluminum alloy, or tin-plated steel. Copper, such as pure copper or brass, has high conductivity and good absorption of high-frequency electromagnetic waves. The thickness of the pure copper shielding layer can be 0.1-0.5mm. Brass combines strength and cost advantages and can be electroplated for corrosion resistance. Aluminum alloy is lightweight, highly corrosion-resistant, and has certain shielding performance, making it suitable for the overall shell manufacturing of outdoor high-voltage equipment. Tin-plated steel is inexpensive and has good shielding effect, making it suitable for cost-sensitive industrial applications. In special scenarios, metal-plated plastic or conductive plastic can also be selected. Metal-plated plastic combines the easy molding properties of plastic with the shielding performance of metal. Conductive plastic with added carbon fiber / metal powder is suitable for indoor scenarios with weak interference. Some sensors also have an additional shielding layer such as pure copper foil inside to enhance protection.
[0031] The aforementioned shielding shell also features three-proof characteristics: waterproof, dustproof, and shockproof. An anti-corrosion coating is sprayed on the surface of the shielding shell, and sealing rings are installed at the interfaces of the battery compartment and high-frequency current sensor to meet the IP65 dustproof and waterproof rating. The internal circuit board is coated with three-proof paint, and shock-absorbing springs can be built into the shell to withstand vibration impacts of ≤5g, making it suitable for harsh operating environments such as outdoor and underground environments.
[0032] In this embodiment, by setting a shielding shell on the high-frequency current sensor, it is possible not only to suppress external electromagnetic interference and ensure the purity of signal acquisition, but also to prevent solid particles from entering the high-frequency current sensor, avoiding short circuits, wear or blockage of components or signal acquisition parts, and protecting the internal circuit from moisture and resisting corrosive substances in the environment, thereby extending its service life.
[0033] Optionally, the overall dimensions of the discharge indicator can be 120mm×80mm×50mm, and the weight can be ≤500g. It can be directly fixed to the high-voltage equipment cabinet or grounding wire using a wall-mounted or magnetic installation method to meet the installation requirements of space-constrained scenarios such as switch cabinets and cable trenches.
[0034] The aforementioned shielding shell also contains a battery compartment, which houses a power supply module that is electrically connected to the circuit board. The power supply module powers the signal processing module on the circuit board.
[0035] Specifically, the battery compartment can be a sealed structure with a waterproof and dustproof design. The power supply module can have three built-in 1.5V alkaline batteries connected in series to output a 4.5V DC voltage. The power supply module can also include a battery management unit connected to the battery compartment. The power management unit integrates a low-power voltage regulator chip, which can stabilize the battery output voltage to 3.3V to power the signal processing module on the circuit board. By optimizing the power management strategy, the discharge indicator's standby current is controlled to within 10μA while ensuring signal quality. The battery life can reach 5-10 years, and the battery compartment supports tool-free battery replacement, making it suitable for long-term unattended outdoor scenarios.
[0036] In one embodiment, please refer to Figure 3 As shown, the signal processing module 120 includes a high-frequency current extraction circuit 121 and a meter driving circuit 122; the high-frequency current extraction circuit 121 is electrically connected to the magnetic coil 11 and the meter driving circuit 122 respectively; the meter driving circuit 122 is also electrically connected to the three-color meter 20.
[0037] The high-frequency current extraction circuit 121 is used to: filter interference signals in the original current signal and amplify them to obtain the target current signal and transmit it to the meter drive circuit; when there is partial discharge in the high-voltage equipment, the target current signal includes a high-frequency discharge signal, which refers to a current signal released by the high-voltage equipment through partial discharge and whose signal frequency is not lower than a preset threshold; the interference signal is a current signal whose signal frequency is lower than the preset threshold; the meter drive circuit 122 is used to: perform voltage conversion processing on the target current signal to obtain the corresponding target voltage signal and transmit it to the three-color meter.
[0038] Specifically, the high-frequency current extraction circuit described above can adopt a passive high-pass filter architecture. The preset threshold corresponding to the cutoff frequency can be customized according to actual needs, for example, set to 500kHz, which can effectively filter out low-frequency interference signals below 500kHz and retain only the target current signal generated by partial discharge. These low-frequency interference signals include, for example, power grid frequency interference and environmental electromagnetic noise.
[0039] The high-frequency current extraction circuit described above may include a pulse feature extraction unit and an amplification unit. The pulse feature extraction unit is used to filter out interference signals in the original current signal and amplify it to obtain the target current signal. The amplification unit is used to amplify the filtered original current signal to an identifiable current range using a low-noise operational amplifier and send it to the meter drive circuit.
[0040] The aforementioned three-color meter can be a magnetoelectric three-color meter. The meter drive circuit is directly connected to the magnetoelectric three-color meter. The three-color meter is used to drive the pointer of the three-color meter to rotate according to the voltage signal output by the meter drive circuit.
[0041] Optionally, the meter drive circuit is specifically used to: classify the target current signal into graded current signals; and perform voltage conversion processing on the graded current signals according to a preset current-to-voltage conversion relationship to generate corresponding target voltage signals; or, perform voltage conversion processing on the target current signal according to a preset current-to-voltage conversion relationship to obtain intermediate voltage signals, and perform graded judgment on the intermediate voltage signals to generate target voltage signals corresponding to the graded judgment results. The target voltage signals include a first voltage signal, a second voltage signal, and a third voltage signal.
[0042] It should be noted that the aforementioned target voltage signal can be a voltage signal including graded information. The meter driving circuit, based on a preset partial discharge intensity grading threshold, performs a comprehensive judgment on the collected target current signal based on multi-level amplitude and pulse frequency, classifying it into three levels: no discharge, mild discharge, and severe discharge, and generating corresponding graded current signals. These graded current signals are current signals after graded processing. Subsequently, according to a preset current-voltage linear conversion relationship, voltage conversion processing is performed on the graded current signals of different levels to generate target voltage signals that correspond one-to-one with the discharge level. Among them, the first voltage signal corresponds to the normal state of no discharge, the second voltage signal corresponds to the warning state of mild discharge, and the third voltage signal corresponds to the fault state of severe discharge. By generating signals of different levels such as the first voltage signal, the second voltage signal, and the third voltage signal, accurate voltage control basis can be provided for the pointer drive and graded display of the three-color meter. The amplitude of the first voltage signal is less than the amplitude of the second voltage signal, and the amplitude of the second voltage signal is less than the amplitude of the third voltage signal.
[0043] In this embodiment, the discharge indicator uses High Frequency Current Detection (HFCT) to monitor partial discharge. First, a high-frequency current signal is acquired by an HFCT sensor. When partial discharge occurs inside the high-voltage equipment, the generated high-frequency current propagates along the grounding wire. The HFCT sensor detects this high-frequency current through electromagnetic induction, converts it into a raw current signal of the same frequency, and transmits it to the high-frequency current extraction circuit on the circuit board. The signal frequency range matches the sensor's 500kHz–20MHz bandwidth design, ensuring no discharge signal is missed. After receiving the raw current signal, the high-frequency current extraction circuit filters out low-frequency interference signals (such as power frequency harmonics and switching power supply noise) with a frequency less than 500kHz according to a preset threshold of 500kHz, retaining only high-frequency signals greater than or equal to 500kHz that reflect the characteristics of partial discharge, thus improving signal purity. The signal is then amplified by an amplification unit to reach the effective detection range, thereby obtaining the target current signal, which is then transmitted to the meter drive circuit.
[0044] As one possible approach, the meter drive circuit can use preset partial discharge intensity grading thresholds (including mild and severe discharge thresholds) to perform dual determination of the amplitude and pulse repetition frequency of the acquired and filtered target current signal. If the amplitude of the target current signal is lower than the mild discharge threshold and the pulse frequency is within the background noise range, it is determined to be a normal state without discharge, generating a first-level signal. If the signal amplitude is between the mild and severe discharge thresholds and the pulse frequency conforms to the characteristics of partial discharge, it is determined to be a mild discharge warning state, generating a second-level signal. If the signal amplitude exceeds the severe discharge threshold and the pulse frequency increases significantly, it is determined to be a severe discharge fault state, generating a third-level signal. Subsequently, the meter drive circuit performs voltage calibration and conversion processing on the above three levels of graded current signals according to a preset current-voltage linear conversion relationship, quantizing the different levels of current signals into corresponding target voltage signals. Specifically, the first graded signal is converted into a first voltage signal, the second graded signal is converted into a second voltage signal, and the third graded signal is converted into a third voltage signal. The three sets of voltage signals output can directly drive the pointer of the three-color meter to realize the graded visualization display of the partial discharge status of high-voltage equipment. The first graded signal, the second graded signal, and the third graded signal are all current signals after graded processing.
[0045] As another possible implementation, the meter drive circuit can first convert the target current signal into a corresponding intermediate voltage signal according to a preset current-to-voltage conversion relationship, and then classify the intermediate voltage signal. If the signal amplitude of the intermediate voltage signal is lower than the mild discharge threshold and the pulse frequency is within the background noise range, it is determined to be a normal state without discharge, and a corresponding first voltage signal is generated. If the signal amplitude of the intermediate voltage signal is between the mild discharge threshold and the severe discharge threshold and the pulse frequency conforms to the characteristics of partial discharge, it is determined to be a mild discharge warning state, and a second voltage signal is generated. If the signal amplitude of the intermediate voltage signal exceeds the severe discharge threshold and the pulse frequency increases significantly, it is determined to be a severe discharge fault state, and a third voltage signal is generated.
[0046] The mild discharge threshold and severe discharge threshold can be customized according to actual needs. For example, the mild discharge threshold can be 0.5 and the severe discharge threshold can be 1.5.
[0047] In this embodiment, the meter driving circuit serves as the link between the high-frequency current extraction circuit and the three-color meter. It can perform grading and voltage conversion processing based on the target current signal, thereby accurately determining the target voltage signal containing grading information. This allows the meter pointer of the three-color meter to rotate stably to the corresponding color display area according to the amplitude of different voltage signals, achieving accurate grading and visualization of the no-discharge, slight-discharge, and heavy-discharge states of high-voltage equipment. At the same time, this circuit adopts a low-power driving architecture, which can complete signal driving without the need for a high-power MCU. This not only synergizes with the low-power design of the sensor, reducing the overall energy consumption of the device to meet the needs of long-term continuous monitoring, but also effectively avoids distortion and interference during signal amplification, ensuring the stability of pointer movement and the accuracy of display results. This facilitates maintenance personnel to quickly and intuitively judge the equipment status and improves on-site monitoring efficiency.
[0048] In one embodiment, please continue to see Figure 2 As shown, the dial is provided with a first color display area 21, a second color display area 22, and a third color display area 23, which are connected sequentially according to their angles; the three-color meter is specifically used for: When the target voltage signal is the first voltage signal, the drive pointer rotates to the first color display area, which is used to indicate that the high-voltage equipment is in a normal state; when the target voltage signal is the second voltage signal, the drive pointer rotates to the second color display area, which is used to indicate that the high-voltage equipment is in a warning state; when the target voltage signal is the third voltage signal, the drive pointer rotates to the third color display area, which is used to indicate that the high-voltage equipment is in a fault state.
[0049] It is understood that the aforementioned three-color meter includes a dial and a pointer mounted on the dial. The dial can include three display areas: a first-color display area, a second-color display area, and a third-color display area. Each color display area is represented by a different color; for example, the first-color display area could be a green sector, the second-color display area a yellow sector, and the third-color display area a red sector. The three-color meter is internally equipped with a magneto-electric drive mechanism, which is connected to the meter's drive circuit. The rotation angle of the pointer in the three-color meter is positively correlated with the input target voltage signal. Different target voltage signals correspond to different amplitudes of pointer drive; the larger the target voltage signal, the greater the amplitude of pointer drive. The pointer can point to the green, yellow, or red area respectively, achieving a visual, hierarchical display of the discharge status.
[0050] For example, when the target voltage signal is the first voltage signal, the drive pointer rotates to the green sector area, indicating that the high-voltage equipment is in a normal state; when the target voltage signal is the second voltage signal, the drive pointer rotates to the yellow sector area, indicating that the high-voltage equipment is in a warning state; when the target voltage signal is the third voltage signal, the drive pointer rotates to the red sector area, indicating that the high-voltage equipment is in a fault state.
[0051] The casing of the aforementioned three-color meter can be made of anti-fog tempered glass, which has shockproof and dustproof properties and is suitable for harsh outdoor operating environments.
[0052] In this embodiment, when the three-color meter performs visual hierarchical display, the pulse repetition frequency can also be set. For example, when the target voltage signal is the first voltage signal, the pointer points to the red area and the corresponding pulse repetition frequency can be less than 1 time / minute; when the target voltage signal is the second voltage signal, the pointer points to the yellow area and the corresponding pulse repetition frequency can be in the range of 1 time / minute ≤ pulse repetition frequency < 10 times / minute; when the target voltage signal is the third voltage signal, the pointer points to red and the corresponding pulse repetition frequency can be greater than or equal to 10 times / minute.
[0053] Understandably, the first color display area indicates that the high-voltage equipment is in normal operation, meaning that the insulation performance of the high-voltage equipment is stable, there is no risk of discharge due to insulation deterioration, and the overall operating status is safe and reliable. The second color display area indicates that the high-voltage equipment is in a mild discharge warning state, meaning that the insulation performance of the high-voltage equipment shows an initial trend of deterioration, there is a potential discharge risk, and the monitoring frequency needs to be increased. The third color display area indicates that the high-voltage equipment is in a severe discharge fault state, meaning that the insulation performance of the high-voltage equipment has been severely deteriorated, there is a clear discharge fault, and immediate shutdown and maintenance are required.
[0054] Optionally, the angle range of the first color display area is greater than the angle range of the third color display area, and the angle range of the third color display area is greater than the angle range of the second color display area.
[0055] The first color display area corresponds to the normal operating state of the high-voltage equipment. The large angle range of this area can intuitively highlight the normal operating conditions of the equipment, making it easy for maintenance personnel to quickly identify the risk-free state. The third color display area corresponds to the severe discharge fault state. Its angle range is the next largest, which can form a conspicuous fault warning area on the dial, prompting that the machine needs to be stopped and repaired immediately. The second color display area, which occupies the smallest area, corresponds to the mild discharge warning state. This design avoids the warning area from occupying too much dial space, and can accurately identify the critical state of the initial deterioration of the equipment's insulation performance, guiding maintenance personnel to increase the monitoring frequency in a timely manner. The overall differentiated design of the angle range matches the actual occurrence probability and handling priority of different operating states of the equipment, improving the practicality and recognizability of the dial display.
[0056] In this embodiment, by setting up a three-color meter, the discharge level can be intuitively displayed through pointer rotation, making it easy for maintenance personnel to quickly identify the operating status of high-voltage equipment by the pointer position. By integrating the high-frequency current sensor and the drive circuit into one unit, the number of external connectors is reduced, and the manufacturing process adopts a standardized surface mount soldering process, which reduces the overall cost by more than 30% compared to traditional split monitoring devices.
[0057] The circuit board can be arranged sequentially according to the signal flow direction of the high-frequency current extraction circuit and the meter drive circuit to shorten the signal transmission path. For example, for the high-frequency current extraction circuit, the line width range is set to 0.8mm to 1.2mm and the line spacing is ≥2mm; for the power line, the line width is ≥2mm; for the ground line, the line width is ≥3mm, thus differentiating the line width and line spacing, and reducing transmission loss through impedance matching. The meter drive circuit can be configured with a micro-current source circuit based on operational amplifiers and precision resistors, which can accurately control the small current output of 0 to 20mA to reduce accuracy error and adapt to the miniaturization design requirements of the device.
[0058] This solution shortens the signal path by rationally arranging and planning the various circuit modules on the circuit board, reduces losses by selecting the line width and line spacing, and precisely controls the small current output by using a micro-current source circuit, while reducing the size of the resistor.
[0059] In one embodiment, the circuit board also integrates a protection circuit, which is electrically connected to the high-frequency current extraction circuit and the meter drive circuit respectively; the protection circuit is used to provide coordinated protection for the high-frequency current extraction circuit and the meter drive circuit.
[0060] It should be noted that by connecting an overcurrent protection element in series at the input of the high-frequency current extraction circuit and a transient suppression diode in parallel at the output, and by connecting a TVS and a fuse at the power input of the meter drive circuit and an RC snubber circuit at the drive signal output, both circuits can be grounded together to suppress surge current, clamp peak voltage, prevent overload or external interference from damaging the components in the circuit, and avoid interference generated when the protection circuit operates affecting the signal quality of the high-frequency current extraction circuit.
[0061] In this embodiment, a protection circuit consisting of a transient suppression diode, a resettable fuse, and an RC snubber circuit is integrated on the PCB to achieve overvoltage and overcurrent protection and suppress voltage spikes, thereby ensuring signal quality.
[0062] To verify the technical performance and practical application effect of the discharge indicator in this application, multi-dimensional tests can be carried out in laboratory simulated working conditions and field pilot environments. First, the test environment is set up and the test object is determined, such as a 10kV oil-immersed transformer. Insulation defects are artificially implanted to simulate partial discharge of varying intensity. Insulation defects include, for example, damaged insulation paper or multiple grounding of the iron core. Interference sources are configured: 50Hz power frequency interference and 100kHz to 500kHz electromagnetic noise interference are introduced to simulate the complex electromagnetic environment on site. Test equipment is prepared, including oscilloscope, spectrum analyzer, and standard partial discharge calibrator.
[0063] During performance testing, frequency band response, anti-interference, low power consumption, and meter accuracy tests can be performed separately. For frequency band response testing, a standard discharge signal of 500kHz to 20MHz is output through a calibrator to test the signal acquisition efficiency of the HFCT sensor. The results show that the sensor's signal response within the design frequency band is ≥95%, with no significant attenuation. For anti-interference testing, a discharge signal with a peak value of 1V is injected into the transformer with the interference source turned on. The discharge indicator can still accurately extract high-frequency characteristic signals, with an interference suppression rate of ≥90%, which is 40% higher than traditional devices. For low power consumption testing, three 1.5V alkaline batteries are used for power supply. The standby current of the recording device is 9.8μA, and the current in continuous detection mode is 50μA. The estimated standby time can reach 8 years, and the continuous detection time can reach 1.5 years, meeting the requirements for long-term operation. For meter accuracy testing, different amplitude drive currents are input. The meter pointer positioning error is ≤2%, and there are no misjudgments or omissions in the graded display.
[0064] During on-site pilot testing, three operating transformers in the substation can be selected for the pilot test. The HFCT sensor in the discharge indicator is installed on the transformer grounding wire. Various tests are performed on the discharge indicator, and the corresponding test results are obtained. It is then determined whether each test result meets the performance requirements. If the performance requirements are met, the discharge indicator is considered to meet the standard, meaning it operates stably, has not experienced malfunctions due to environmental vibration or humidity, and its three-proof performance (proof, damping, and corrosion protection) is up to standard. Determining whether the test results meet the performance requirements can be done by checking whether the frequency response characteristics, low power consumption performance, and anti-interference capability all meet the design specifications. If all of these meet the design specifications, then the performance requirements are met.
[0065] The test results show that the HFCT sensor in this solution meets the design specifications in terms of frequency response characteristics, low power consumption performance, and anti-interference capability. The three-color meter can realize accurate visualization of discharge classification. The overall performance is better than traditional partial discharge monitoring equipment, and it is feasible for large-scale engineering applications.
[0066] The discharge indicator provided in this application can be applied to scenarios such as power system substations, transmission and distribution lines, and industrial high-voltage equipment, providing a low-cost and highly reliable solution for equipment condition-based maintenance and fault early warning. It can also be applied to fields such as smart grids and new energy equipment monitoring.
[0067] Compared with existing technologies, the discharge indicator in this solution directly connects a high-frequency current sensor to a three-color meter, and integrates a magnetic coil and circuit board within the sensor. This avoids the use of high-power components such as independent general-purpose detection devices found in traditional devices, significantly reducing overall power consumption and size while meeting the needs of long-term continuous monitoring. The magnetic coil non-invasively collects the original current signal of the high-voltage equipment's grounding wire based on the principle of electromagnetic induction, enabling real-time live detection without shutting down the equipment. This is convenient to operate and does not affect the normal operation of the equipment, allowing for long-term discharge status monitoring. Furthermore, the signal processing module is integrated inside the sensor, enabling signal extraction and voltage conversion of the original current signal without long-distance transmission, reducing signal loss and interference in the signal transmission process and ensuring signal accuracy and the highest detection precision. Finally, the rotation of the pointer in the three-color meter provides a visual, hierarchical display of the partial discharge status, allowing maintenance personnel to intuitively and quickly determine the status of the high-voltage equipment, significantly improving the efficiency of high-voltage equipment status detection.
[0068] On the other hand, this application also provides a discharge detection method, such as Figure 4 As shown, the discharge detection method is applied to the above-mentioned discharge indicator and includes the following steps S201 to S203. Wherein: Step S201: The original current signal of the grounding wire of the high-voltage equipment is acquired by electromagnetic induction through a magnetic coil and transmitted to the signal processing module.
[0069] In step S202, the original current signal is extracted and converted into a voltage signal by the signal processing module to obtain a voltage signal, which is then transmitted to the three-color meter.
[0070] In step S203, the three-color meter receives and responds to the voltage signal, driving the pointer in the dial to rotate, so as to perform a visual graded display of the discharge.
[0071] Specifically, the aforementioned magnetic coil is installed on the grounding wire of the high-voltage equipment. Based on the principle of electromagnetic induction, the magnetic coil obtains the high-frequency pulse current generated by partial discharge of the high-voltage equipment in the grounding wire, generates the original current signal, and directly transmits it to the signal processing module. This non-invasive acquisition method does not require disassembling the equipment or interrupting the normal operation of the high-voltage equipment. It can avoid damage to the equipment body and capture the real discharge current characteristics in real time, providing accurate and reliable raw data support for subsequent signal processing.
[0072] The signal processing module includes a high-frequency current extraction circuit and a meter driving circuit. The high-frequency current extraction circuit receives the raw current signal from the magnetic coil and performs filtering, amplification, and other signal extraction operations on the raw current signal to eliminate environmental electromagnetic interference and background interference signals. It then selects the target current signal strongly correlated with partial discharge and transmits it to the meter driving circuit. The meter driving circuit quantizes the effective current signal into a target voltage signal corresponding to the discharge level according to a preset current-voltage linear conversion relationship and transmits it to the three-color meter. After receiving the target voltage signal, the three-color meter precisely drives the pointer to the corresponding color display area through an internal drive mechanism. When the high-voltage equipment is in a normal state, the pointer of the three-color meter is driven to the green display area; when the high-voltage equipment is in a warning state, the pointer of the three-color meter is driven to the yellow display area; when the high-voltage equipment is in a fault state, the pointer of the three-color meter is driven to the red display area. This enables a visual and hierarchical display of the high-voltage equipment's no-discharge, mild-discharge, and severe-discharge states, allowing maintenance personnel to intuitively and quickly determine the equipment's operating status without the need for specialized instruments, significantly improving on-site monitoring efficiency and the timeliness of fault warnings.
[0073] This application provides a discharge detection method. Compared with existing technologies, it directly connects a high-frequency current sensor to a three-color meter, and integrates a magnetic coil and circuit board within the sensor. This avoids the use of high-power components such as independent general-purpose detection equipment found in traditional devices, significantly reducing overall power consumption and size while meeting the needs of long-term continuous monitoring. The magnetic coil non-invasively collects the original current signal of the high-voltage equipment's grounding wire based on the principle of electromagnetic induction, enabling real-time live detection without shutting down the equipment. This method is convenient to operate and does not affect the normal operation of the equipment, allowing for long-term discharge status monitoring. Furthermore, the signal processing module is integrated inside the sensor, enabling signal extraction and voltage conversion of the original current signal without long-distance transmission, reducing signal transmission losses and interference, and ensuring signal accuracy and the highest detection precision. Finally, the rotation of the pointer in the three-color meter enables a visual, hierarchical display of the partial discharge status, facilitating maintenance personnel to intuitively and quickly determine the status of the high-voltage equipment, significantly improving the efficiency of high-voltage equipment status detection.
[0074] Those skilled in the art will understand that the structures shown in the above embodiments are merely block diagrams of some structures related to the present application and do not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than shown in the figures, or combine certain components, or have different component arrangements.
[0075] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0076] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.
Claims
1. A discharge indicator, characterized in that, The discharge indicator includes: A high-frequency current sensor and a three-color meter electrically connected to the high-frequency current sensor are provided. The high-frequency current sensor is installed on the grounding wire of the high-voltage equipment. The high-frequency current sensor has a circuit board and a magnetic coil electrically connected to the circuit board inside. A signal processing module is integrated on the circuit board. The magnetic coil is used to: collect the original current signal of the grounding wire of the high-voltage equipment by electromagnetic induction and transmit it to the signal processing module; The signal processing module is used to: extract and convert the original current signal to obtain the target voltage signal and transmit it to the three-color meter; The three-color meter is used to: receive and respond to the target voltage signal, drive the pointer in the dial to perform a rotation operation, so as to visually and hierarchically display the partial discharge status of the high-voltage equipment.
2. The discharge indicator according to claim 1, characterized in that, The signal processing module includes a high-frequency current extraction circuit and a meter driving circuit; the high-frequency current extraction circuit is electrically connected to the magnetic coil and the meter driving circuit respectively; the meter driving circuit is also electrically connected to the three-color meter. The high-frequency current extraction circuit is used to: filter interference signals in the original current signal and amplify them to obtain the target current signal and transmit it to the meter drive circuit; when the high-voltage equipment has partial discharge, the target current signal includes a high-frequency discharge signal, which refers to a current signal released by the high-voltage equipment through partial discharge and whose signal frequency is not lower than a preset threshold; the interference signal is a current signal whose signal frequency is lower than the preset threshold. The meter driving circuit is used to: perform voltage conversion processing on the target current signal to obtain the corresponding target voltage signal and transmit it to the three-color meter.
3. The discharge indicator according to claim 2, characterized in that, The meter drive circuit is specifically used for: The target current signal is graded to obtain graded current signals; and according to a preset current-to-voltage conversion relationship, the graded current signals are subjected to voltage conversion processing to generate corresponding target voltage signals; or... According to the preset current-voltage conversion relationship, the target current signal is subjected to voltage conversion processing to obtain an intermediate voltage signal, and the intermediate voltage signal is graded and judged to generate a target voltage signal corresponding to the graded judgment result; the target voltage signal includes a first voltage signal, a second voltage signal and a third voltage signal.
4. The discharge indicator according to claim 3, characterized in that, The dial is provided with a first color display area, a second color display area, and a third color display area that are sequentially connected according to an angle; the three-color meter is specifically used for: When the target voltage signal is the first voltage signal, the pointer is driven to rotate to the first color display area, which is used to indicate that the high voltage equipment is in a normal state. When the target voltage signal is the second voltage signal, the pointer is driven to rotate to the second color display area, which is used to indicate that the high-voltage equipment is in a warning state. When the target voltage signal is the third voltage signal, the pointer is driven to rotate to the third color display area, which is used to indicate that the high-voltage equipment is in a fault state; the amplitude of the first voltage signal is less than the amplitude of the second voltage signal, and the amplitude of the second voltage signal is less than the amplitude of the third voltage signal.
5. The discharge indicator according to claim 4, characterized in that, The angle range of the first color display area is greater than the angle range of the third color display area, and the angle range of the third color display area is greater than the angle range of the second color display area.
6. The discharge indicator according to claim 1, characterized in that, The high-frequency current sensor also includes a shielding housing, and the magnetic coil and the circuit board are installed inside the shielding housing; The shielding housing is used to shield the high-frequency current sensor from external electromagnetic interference.
7. The discharge indicator according to claim 6, characterized in that, The shielding shell also contains a battery compartment, in which a power supply module is installed. The power supply module is electrically connected to the circuit board. The power supply module is used to supply power to the signal processing module on the circuit board.
8. The discharge indicator according to claim 1, characterized in that, The signal bandwidth of the high-frequency current sensor is 500kHz to 20MHz.
9. The discharge indicator according to claim 1, characterized in that, The circuit board also integrates a protection circuit, which is electrically connected to the high-frequency current extraction circuit and the meter drive circuit respectively. The protection circuit is used to provide coordinated protection for the high-frequency current extraction circuit and the meter drive circuit.
10. A discharge detection method, characterized in that, The discharge detection method is applied to the discharge indicator as described in any one of claims 1-9, the method comprising: The original current signal of the grounding wire of the high-voltage equipment is acquired by electromagnetic induction using a magnetic coil and transmitted to the signal processing module. The signal processing module extracts and converts the original current signal to obtain the target voltage signal, which is then transmitted to the three-color meter. The tri-color meter receives and responds to the target voltage signal, driving the pointer in the dial to rotate, thereby visually and hierarchically displaying the partial discharge status of the high-voltage equipment.