An adaptive compensation voltage dividing device based on self-powering of sleeve end screen

Abstract

This invention discloses an adaptive compensation voltage divider device based on self-powered bushing end screen. It includes an energy acquisition module that obtains displacement current from the bushing end screen side as power for the voltage monitoring device, and uses a clamping network to protect the circuit from overvoltage damage, converting the AC signal into DC energy. A modulation output module adjusts the equivalent impedance according to the characteristics of the downstream load to optimize power conditions, stores electrical energy, and outputs a measurement signal corresponding to the bushing operating voltage in a timely manner. An adaptive compensation module calculates the operating voltage based on the voltage sampling signal, dynamically updates the compensation coefficient to ensure the accuracy and stability of the voltage divider ratio, and monitors system status feedback information to update the compensation parameters. Implementing this device ensures the accuracy and stability of voltage monitoring, eliminates interference from external leads, and significantly improves the system's anti-interference capability and long-term operational reliability.

Description

Technical Field

[0001] This invention relates to the field of high-voltage bushing voltage monitoring system technology, and in particular to an adaptive compensation voltage divider device based on the self-powered end screen of the bushing. Background Technology

[0002] With the continuous improvement of power system voltage levels and transmission capacity, the insulation reliability of transformer bushings has become a key factor restricting the safe operation of the power grid. As the core insulation component of power transformers, the operating status of high-voltage bushings directly affects the stability of the entire power grid. Accurate end-screen signals are fundamental to assessing the insulation health of bushings. By sensing their capacitance, partial discharge characteristics, and other status parameters, potential defects can be detected early, preventing unplanned outages or even equipment damage due to insulation faults, and improving the economy and safety of power grid operation. Therefore, developing an efficient and reliable bushing condition monitoring technology is crucial for ensuring the stable operation of the power system.

[0003] Currently, bushing condition monitoring mainly relies on acquiring online monitoring parameters such as discharge signals and oil chromatography. However, traditional passive bushing end-screen voltage dividers typically use fixed capacitors or fixed resistors as the low-voltage arm, a method with significant drawbacks under long-term online monitoring conditions. Because the fixed parameters of the voltage divider cannot adaptively adjust to factors such as changes in the high-voltage bushing capacitance, grid voltage fluctuations, and ambient temperature changes, the measurement accuracy is easily affected by external factors. This makes it difficult to guarantee the stability and accuracy of measurements during long-term operation, thus affecting the accurate judgment of the high-voltage equipment's operating status. On the other hand, while active voltage dividers with adjustable voltage ratios offer greater flexibility, they rely on external power supplies. This not only increases insulation risks but also makes them susceptible to electromagnetic interference, which is detrimental to the accuracy and stability of voltage monitoring.

[0004] Therefore, it is necessary to design a new device that can achieve self-powering by utilizing the displacement current generated when the end screen is grounded, and dynamically adjust the voltage division ratio in combination with an adaptive compensation module to ensure the accuracy and stability of voltage monitoring. This not only eliminates the interference caused by external leads, but also significantly improves the system's anti-interference capability and long-term operational reliability, making it particularly suitable for condition monitoring scenarios of high-voltage and ultra-high-voltage bushings. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide an adaptive compensation voltage divider device based on self-powering of the bushing end screen.

[0006] To solve the above-mentioned technical problems, the purpose of this invention is achieved through the following technical solution: providing an adaptive compensation voltage divider device based on self-powering of the bushing end screen, characterized in that it includes: an energy acquisition module, a modulation output module, and an adaptive compensation module; The power acquisition module is used to safely acquire displacement current and voltage sampling signals from the bushing end screen side to power the voltage monitoring device, limit the current, use a clamping network to protect the circuit from overvoltage damage, and convert AC signals into DC energy. The modulation output module is used to adjust the equivalent impedance according to the characteristics of the downstream load to optimize the power conditions, store the DC energy from the power acquisition module, and output a measurement signal corresponding to the bushing operating voltage when the energy storage reaches the requirement. The adaptive compensation module is used to calculate the bushing operating voltage based on the voltage sampling signal of the power acquisition module, and dynamically update the compensation coefficient to ensure the accuracy and stability of the voltage division ratio, monitor the system operating status and provide feedback information for updating the compensation parameters.

[0007] The further technical solution is as follows: the power acquisition module includes a signal acquisition unit, a safety overvoltage protection unit, and a rectification unit connected in sequence. The signal acquisition unit is used to extract displacement current and voltage sampling signals from the end screen side of the high-voltage bushing. The safety overvoltage protection unit is used to clamp and limit the displacement current. The rectification unit is used to rectify the clamped and limited AC current signal and convert it into DC energy.

[0008] The further technical solution is as follows: the signal acquisition unit includes a series resistor and a coupling capacitor connected in sequence, which is used to ensure that the displacement current component is extracted without changing the original equivalent grounding characteristics of the bushing.

[0009] The further technical solution is as follows: the safety overvoltage protection unit includes a clamping network; the rectifier unit includes a multi-stage voltage multiplier rectifier circuit and an energy storage capacitor connected in sequence, the clamping network is connected to the coupling capacitor; the multi-stage voltage multiplier rectifier circuit is connected to the clamping network; and the energy storage capacitor is connected to the modulation output module.

[0010] The further technical solution is as follows: the modulation output module includes an impedance matching unit, an energy accumulation unit, and a control output unit; the control output unit is connected to an output branch, and the impedance matching unit is used to adjust the equivalent impedance of the modulation output branch to ensure optimal energy transmission conditions without changing the electrical characteristics of the end screen. The power accumulation unit is used to further store and buffer the DC energy from the power acquisition module; The control output unit is used to monitor the energy storage status and drive the modulation output branch to generate a measurement signal corresponding to the bushing operating voltage when the energy is sufficient, while limiting or shutting down the output when the energy storage is insufficient.

[0011] The further technical solution is as follows: the impedance matching unit is used to adjust the equivalent impedance of the modulation output branch through a resistor-capacitor combination network.

[0012] The further technical solution is as follows: The adaptive compensation module includes a voltage divider calculation unit, a compensation adjustment unit, and a status monitoring unit. The voltage divider calculation unit is used to calculate the operating voltage based on the voltage sampling signal on the end screen side and the equivalent capacitance distribution of the bushing by combining a fixed proportional coefficient and a status correction term. The compensation adjustment unit is used to dynamically update the compensation coefficient according to the real-time monitored operating status information and adjust the voltage divider capacitor using linear interpolation to correct the measurement deviation. The status monitoring unit is used to monitor the working status of the adaptive compensation module and the changes in the bushing operating parameters, obtain status information, and feed the status information back to the compensation adjustment unit for adjustment.

[0013] The further technical solution is as follows: the voltage divider calculation unit is connected to the signal acquisition terminal of the voltage monitoring device; wherein, the bushing is equivalent to a multi-layer capacitor series structure, and the voltage of the final screen V2 and the main voltage of the bushing V1 satisfy an approximate proportional relationship: The proportionality coefficient k0 is determined by the bushing structure parameters, the equivalent capacitance of the end screen, and the voltage divider network parameters. With the proportionality coefficient fixed, a state correction term is added. Where k0 is the factory-calibrated basic partial pressure coefficient; k1 is the compensation coefficient dynamically updated by the compensation adjustment unit.

[0014] The further technical solution is as follows: The compensation adjustment unit is used to select and linearly interpolate the compensation coefficient from the pre-stored parameter table based on the calculation results of the voltage divider calculation unit and the current operating status, so as to correct the measurement error caused by environmental or equipment changes, and feed back the updated parameters to the voltage divider calculation unit for adjustment.

[0015] The further technical solution is as follows: the adaptive compensation module also includes a control unit, which is connected to the voltage divider calculation unit, the compensation adjustment unit and the status monitoring unit. The status monitoring unit is used to monitor the working status of the adaptive compensation module and the running status of the bushing based on the temperature sensor built into the control unit and the voltage divider capacitor in conjunction with the ADC channel.

[0016] The advantages of this invention compared to existing technologies are as follows: This invention achieves safe self-powered operation by acquiring displacement current from the bushing's end screen side through an energy acquisition module, and converts the AC signal into DC energy for subsequent use. Simultaneously, the device utilizes a modulation output module to adjust the equivalent impedance according to load characteristics to optimize power conditions and store DC energy. When the energy storage meets the requirements, it accurately outputs a measurement signal corresponding to the bushing's operating voltage. Specifically, the adaptive compensation module calculates the operating voltage based on the voltage sampling signal, dynamically updates the compensation coefficient to ensure the accuracy and stability of the voltage division ratio, monitors the system status in real time, and provides feedback information for adjusting compensation parameters. This method not only eliminates interference from external leads but also significantly improves the system's anti-interference capability and long-term operational reliability, making it particularly suitable for high-voltage and ultra-high-voltage bushing status monitoring scenarios. Through the above design, high-precision monitoring and feedback of bushing voltage are achieved, maintaining excellent performance even under complex operating conditions.

[0017] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of an adaptive compensation voltage divider device based on self-powering of the bushing end screen, provided in an embodiment of the present invention. Figure 2 A schematic diagram illustrating the use of an adaptive compensation voltage divider device based on self-powering of the bushing end screen, provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the power acquisition module provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the modulation output module provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the adaptive compensation module provided in an embodiment of the present invention; Explanation of the markings in the image: 10. Power Acquisition Module; 11. Signal Acquisition Unit; 12. Overvoltage Protection Unit; 13. Rectifier Unit; 20. Modulation Output Module; 21. Impedance Matching Unit; 22. Power Accumulation Unit; 23. Control Output Unit; 30. Adaptive Compensation Module; 31. Voltage Divider Calculation Unit; 32. Compensation Adjustment Unit; 33. Status Monitoring Unit. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0022] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0023] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0024] With the increasing voltage levels and transmission capacity of power systems, the reliability of transformer bushing insulation has become crucial to the safe operation of the power grid. Existing bushing condition monitoring technologies mainly rely on passive voltage dividers with fixed parameters or active voltage dividers dependent on external power sources. The former suffers from inability to adaptively adjust parameters, leading to measurement accuracy being greatly affected by external factors, while the latter increases insulation risks and electromagnetic interference, hindering long-term stable monitoring. Therefore, developing a highly efficient bushing condition monitoring technology capable of adaptive adjustment, reducing external dependence, and improving monitoring accuracy and stability is essential for ensuring the safe and economical operation of the power system. This technology must accurately assess the health status of bushing insulation, detect potential defects early, and prevent unplanned outages and equipment damage.

[0025] To address this, this invention provides an adaptive compensation voltage divider device based on self-powered bushing end screen. This device achieves self-powered operation by utilizing the displacement current generated when the end screen is grounded. Combined with the adaptive compensation module 30, the voltage divider ratio is dynamically adjusted, ensuring the accuracy and stability of voltage monitoring. This not only eliminates interference from external leads but also significantly improves the system's anti-interference capability and long-term operational reliability. It is particularly suitable for status monitoring scenarios of high-voltage and ultra-high-voltage bushings.

[0026] The device safely acquires displacement current and voltage sampling signals from the bushing's end screen side via the power acquisition module 10, converting them into DC energy for system use. A clamping network protects the circuit from overvoltage damage. The modulation output module 20 adjusts the equivalent impedance to optimize power conditions based on the downstream load characteristics, stores and outputs measurement signals corresponding to the bushing's operating voltage as needed. The core adaptive compensation module 30 dynamically updates the compensation coefficient using the voltage sampling signal, ensuring an accurate and stable voltage division ratio. It also monitors system status feedback for parameter adjustment, achieving high-precision and stable voltage monitoring. This design not only eliminates external power supply dependence and lead interference but also enhances the system's anti-interference capability and long-term operational reliability. It is particularly suitable for status monitoring of high-voltage and ultra-high-voltage bushings, effectively improving the safety and stability of the power system.

[0027] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0028] Please see Figures 1 to 2 An adaptive compensation voltage divider device based on self-powered end screen of bushing includes: power acquisition module 10, modulation output module 20 and adaptive compensation module 30. Among them, the power acquisition module 10 is used to safely acquire displacement current and voltage sampling signals from the bushing end screen side to power the voltage monitoring device, limit the current, use clamping network to protect the circuit from overvoltage damage, and convert AC signals into DC energy. The modulation output module 20 is used to adjust the equivalent impedance according to the characteristics of the downstream load to optimize the power conditions, store the DC energy from the power acquisition module 10, and output a measurement signal corresponding to the bushing operating voltage when the energy storage reaches the requirement. The adaptive compensation module 30 is used to calculate the bushing operating voltage based on the voltage sampling signal of the power acquisition module 10, and dynamically update the compensation coefficient to ensure the accuracy and stability of the voltage division ratio, monitor the system operating status and provide feedback information for updating the compensation parameters.

[0029] Please see Figure 2This embodiment provides an adaptive compensation voltage divider device based on self-powered bushing end screen. This device is precisely designed and fully functional, mainly comprising three core modules: a power acquisition module 10, a modulation output module 20, and an adaptive compensation module 30. First, the power acquisition module 10 is the foundation of the entire system. It is responsible for safely acquiring displacement current and voltage sampling signals from the end screen side of the high-voltage bushing and converting them into usable DC energy. Specifically, the current signal acquisition unit 11 is directly connected to the bushing end screen through a high-resistance series resistor and coupling capacitor, ensuring that the displacement current component is extracted without altering the original equivalent grounding characteristics of the bushing. This design not only guarantees the safe acquisition of current but also avoids interference with the original electrical characteristics of the bushing. Furthermore, to protect the circuit from overvoltage damage, the safety overvoltage protection unit 12 employs clamping network technology, which effectively limits the voltage flowing into the rectifier unit 13, preventing circuit damage caused by lightning strikes or operational overvoltages. Finally, the rectifier unit 13 uses a multi-stage voltage multiplier rectifier circuit to convert AC signals into DC energy and stores this energy through an energy storage capacitor, thereby providing a stable and reliable power supply for the voltage monitoring device.

[0030] Next, the modulation output module 20 is responsible for adjusting the equivalent impedance according to the characteristics of the downstream load to optimize power conditions, and also for storing DC energy from the power acquisition module 10. When the energy storage reaches the required level, the modulation output module 20 outputs a measurement signal corresponding to the bushing operating voltage. This module includes an impedance matching unit 21, an energy accumulation unit 22, and a control output unit 23. The impedance matching unit 21 uses a resistor-capacitor combination network to adjust the equivalent impedance of the modulation output branch, ensuring optimal energy transmission conditions without changing the electrical characteristics of the final screen, which is crucial for improving the overall efficiency of the system. The energy accumulation unit 22 further stores and buffers the DC energy from the power acquisition module 10, enabling the system to maintain normal operation even when the displacement current power is limited. The control output unit 23 monitors the energy storage status and drives the modulation output branch to generate a measurement signal when the energy is sufficient; when the energy storage is insufficient, it takes measures to limit or shut down the output to ensure the stability and reliability of the system.

[0031] Finally, the adaptive compensation module 30 is a crucial component for ensuring the accuracy and stability of voltage monitoring. It calculates the bushing operating voltage based on the voltage sampling signal provided by the power acquisition module 10 and dynamically updates the compensation coefficients to ensure the accuracy and stability of the voltage division ratio. This module also monitors the system's operating status and provides feedback for updating compensation parameters. Specifically, the voltage division calculation unit 31 uses a fixed proportional coefficient plus a state correction term, combined with the bushing's equivalent capacitance distribution and voltage division relationship, to calculate the operating voltage. This method effectively addresses measurement errors caused by environmental changes or equipment aging. The compensation adjustment unit 32 dynamically updates the compensation coefficients based on the current operating status information, correcting measurement deviations by introducing compensation coefficients or adjustment algorithms to ensure the output voltage signal remains within a predetermined accuracy range. The status monitoring unit 33 monitors the operating status of the adaptive compensation module 30 and changes in bushing operating parameters, acquires status information, and feeds this information back to the compensation adjustment unit 32 for parameter adjustment. This real-time monitoring and feedback mechanism significantly improves the system's reliability and adaptability.

[0032] In summary, the adaptive compensation voltage divider device based on self-powered bushing end screen proposed in this embodiment not only achieves long-term online voltage monitoring without external power connection, but also significantly improves the accuracy and stability of voltage monitoring by dynamically adjusting the voltage division ratio. It is suitable for condition monitoring scenarios of high-voltage and ultra-high-voltage bushings. Its unique design concept and technical solution demonstrate enormous potential and application value in improving the safety of power equipment and reducing operation and maintenance costs.

[0033] In one embodiment, please refer to Figure 3 The aforementioned power acquisition module 10 includes a signal acquisition unit 11, a safety overvoltage protection unit 12, and a rectification unit 13 connected in sequence. The signal acquisition unit 11 is used to extract displacement current and voltage sampling signals from the end screen side of the high-voltage bushing; the safety overvoltage protection unit 12 is used to clamp and limit the displacement current; and the rectification unit 13 is used to rectify the clamped and limited AC current signal and convert it into DC energy.

[0034] In one embodiment, please refer to Figure 3 The aforementioned signal acquisition unit 11 includes a series resistor and a coupling capacitor connected in sequence to ensure that the displacement current component is extracted without changing the original equivalent grounding characteristics of the bushing.

[0035] In one embodiment, please refer to Figure 3 The aforementioned safety overvoltage protection unit 12 includes a clamping network; the rectifier unit 13 includes a multi-stage voltage multiplier rectifier circuit and an energy storage capacitor connected in sequence, the clamping network is connected to the coupling capacitor; the multi-stage voltage multiplier rectifier circuit is connected to the clamping network; and the energy storage capacitor is connected to the modulation output module 20.

[0036] In one embodiment, such as Figure 3 As shown, the power acquisition module 10 is designed to safely and efficiently acquire displacement current and voltage sampling signals from the end screen side of the high-voltage bushing, and convert these signals into DC energy that can be used subsequently. The module includes three main components: a signal acquisition unit 11, a safe overvoltage protection unit 12, and a rectification unit 13.

[0037] The signal acquisition unit 11 is the foundation of the entire power acquisition module 10. Its function is to extract displacement current and voltage sampling signals from the end screen side of the high-voltage bushing. Specifically, the signal acquisition unit 11 consists of a series resistor and a coupling capacitor, which are connected in sequence to ensure that the displacement current component is extracted without changing the original equivalent grounding characteristics of the bushing. The series resistor has high resistance characteristics, and it works together with the coupling capacitor to ensure current extraction while avoiding interference with the original electrical characteristics of the bushing. This design not only ensures the safe acquisition of current but also maintains the integrity of the original insulation structure of the bushing.

[0038] The safety overvoltage protection unit 12 is used to clamp and limit the displacement current obtained through the signal acquisition unit 11 to prevent circuit damage caused by lightning strikes or operational overvoltages. This unit mainly includes a clamping network, which is positioned after the signal acquisition unit 11 (i.e., the coupling capacitor) and before the rectifier unit 13. The function of the clamping network is to limit the voltage entering the rectifier unit 13 under abnormal conditions, ensuring that the voltage flowing into the rectifier unit 13 does not exceed a set safety threshold. This measure is crucial for protecting the circuit from overvoltage damage, especially in high-voltage equipment operating environments, where unpredictable operational overvoltages or lightning strike risks are particularly important.

[0039] The rectifier unit 13 is responsible for converting the AC current signal processed by the clamping network into DC energy to provide a stable power supply for the subsequent modulation output module 20. The rectifier unit 13 consists of a multi-stage voltage multiplier rectifier circuit and an energy storage capacitor. The multi-stage voltage multiplier rectifier circuit progressively increases the voltage level of the input AC signal and converts it into DC, achieving time-accumulated energy acquisition under low-power conditions. The energy storage capacitor stores the DC energy processed by the multi-stage voltage multiplier rectifier circuit, providing a continuous power supply for the modulation output module 20. The presence of the energy storage capacitor ensures that the system maintains a stable operating state even when the displacement current power is limited, thus guaranteeing the reliability of the system.

[0040] In summary, the power acquisition module 10 of this embodiment acquires the current signal from the bushing's end screen side and converts it into a power supply suitable for powering the voltage monitoring device. The current signal acquisition module, as the front-end part directly connected to the end screen, achieves controllable extraction of the displacement current through the coordinated configuration of a high-resistance series resistor and a coupling capacitor. This design effectively extracts the displacement current component generated by the end screen under AC operating voltage without altering the original equivalent grounding characteristics of the bushing's end screen, while strictly limiting the amplitude of this current. The safety overvoltage protection module is located between the current signal acquisition module and the rectifier module, employing a clamping network structure that works in conjunction with the current-limiting resistor. Its function is to clamp and limit the voltage entering the rectifier module in the event of lightning strikes, operational overvoltages, or abnormal operating conditions, thereby preventing abnormal changes in the end screen potential or damage to subsequent circuits. The AC signal rectification module adopts a multi-stage voltage multiplier rectifier circuit combined with an energy storage capacitor to rectify the AC signal corresponding to the displacement current and realize the periodic accumulation and storage of energy through the energy storage element, thereby providing a continuous and stable power supply for the low-power voltage monitoring device.

[0041] During normal operation of the bushing, the last screen generates a displacement current under the excitation of the power frequency AC voltage. After high-impedance current limiting and coupling treatment, only a very small portion of this current enters the impedance matching branch and is applied to the voltage multiplier rectifier network without significantly changing the potential distribution of the last screen. Considering the relatively high amplitude of the AC signal and the small amplitude of the displacement current in the last screen, this invention uses a multi-stage voltage multiplier rectifier structure to progressively increase the AC voltage and store it in the energy storage capacitor, thereby achieving time-accumulated energy acquisition under low-power conditions and providing a stable operating power supply for the voltage monitoring device.

[0042] The power acquisition module 10, through its carefully designed signal acquisition unit 11, overvoltage protection unit 12, and rectifier unit 13, achieves the goal of safely acquiring displacement current and voltage sampling signals from the end screen side of the high-voltage bushing and converting them into stable DC energy for subsequent use. This design not only solves the power supply problem existing in traditional methods but also significantly improves the safety of power equipment, reduces operation and maintenance costs, and demonstrates its great application potential in high-voltage transformer bushing condition monitoring.

[0043] In one embodiment, please refer to Figure 4 The modulation output module 20 mentioned above includes an impedance matching unit 21, an energy accumulation unit 22, and a control output unit 23. The control output unit 23 is connected to an output branch, and the impedance matching unit 21 is used to adjust the equivalent impedance of the modulation output branch to ensure optimal energy transmission conditions without changing the electrical characteristics of the end screen. The power accumulation unit 22 is used to further store and buffer the DC energy from the power acquisition module 10; The control output unit 23 is used to monitor the energy storage status and drive the modulation output branch to generate a measurement signal corresponding to the bushing operating voltage when the energy is sufficient, while limiting or shutting down the output when the energy storage is insufficient.

[0044] In one embodiment, please refer to Figure 4 The impedance matching unit 21 mentioned above is used to adjust the equivalent impedance of the modulation output branch through a resistor-capacitor combination network.

[0045] In one embodiment, such as Figure 4 As shown, the modulation output module 20 is one of the key components in the adaptive compensation voltage monitoring system based on the self-powered bushing end screen. It aims to effectively manage and utilize the energy acquired from the power acquisition module 10, and generate a measurement signal corresponding to the operating voltage of the high-voltage bushing when necessary. This module mainly includes three main units: an impedance matching unit 21, an energy accumulation unit 22, and a control output unit 23.

[0046] Impedance matching unit 21 is mainly used to adjust the equivalent impedance of the modulation output branch to ensure optimal energy transfer conditions without changing the electrical characteristics of the final screen. Specifically, this unit accomplishes this task through a resistor-capacitor combination network. The selection and configuration of resistors and capacitors need to be carefully designed based on the characteristics of the final screen displacement current energy harvesting circuit and the requirements of the subsequent load. This design not only ensures maximum energy transfer efficiency but also avoids additional losses or interference with the original electrical characteristics of the final screen caused by improper impedance matching. By precisely adjusting the equivalent impedance, impedance matching unit 21 can minimize the impact on the potential distribution of the final screen while ensuring system stability and efficiency.

[0047] The energy accumulation unit 22 is located after the impedance matching unit 21. Its main function is to further store and buffer the DC energy from the energy acquisition module 10. Considering the limited power of the displacement current at the end screen, the instantaneous power is often insufficient to support continuous power supply requirements. Therefore, the design of the energy accumulation unit 22 is crucial. This unit uses an energy storage capacitor as its core component, which can periodically accumulate the small amount of DC energy provided by the energy acquisition module 10 to form a stable energy reserve. This allows the modulation output module 20 to maintain normal operation even when the displacement current power is low, providing the necessary energy foundation for subsequent control output.

[0048] The control output unit 23 is the "brain" of the entire modulation output module 20. It is responsible for monitoring the energy storage status and driving the modulation output branch to generate a measurement signal corresponding to the bushing operating voltage when energy is sufficient. Simultaneously, when energy storage is insufficient, the control output unit 23 will limit or shut down the output, thereby ensuring the stable operation of the entire system under self-powered conditions. This unit is closely connected to the energy accumulation unit 22, and determines whether to initiate the modulation output process by real-time monitoring of the energy storage status. Furthermore, the control output unit 23 also has data transmission capabilities, capable of converting the measured voltage signal into an electrical signal and safely transmitting it to external secondary side equipment via optical fiber or other media, enabling remote monitoring of the high-voltage bushing's operating status.

[0049] In summary, the modulation output module 20 functions to optimize the impedance, manage energy, and control the output of the electrical signal on the end screen side under the self-powered condition provided by the power acquisition module 10, thereby achieving stable measurement and output of the voltage signal. The impedance matching unit 21 is connected to the rectifier and energy storage output terminals of the power acquisition module 10 and adopts a resistor-capacitor combined network structure. It is used to match and adjust the equivalent impedance of the modulation output branch according to the end screen displacement current energy harvesting circuit and the characteristics of the subsequent load, so that the modulation output module 20 obtains relatively optimal output power conditions under operating conditions without significantly changing the electrical characteristics of the end screen. The energy accumulation unit 22 is located after the impedance matching unit 21 and is used to further store and buffer the DC energy from the power acquisition module 10. Through this unit, the modulation output module 20 can still achieve energy accumulation over time under the condition of limited power of the end screen displacement current, and uses energy storage capacitors to provide the necessary energy foundation for subsequent control output. The control output unit 23 is connected to the energy accumulation unit 22 and is used to control the working state of the modulation output module 20, drive the modulation output module 20 to enter the working state, and output a measurement signal corresponding to the bushing operating voltage to realize voltage measurement or data transmission. When insufficient energy storage is detected, the control output unit 23 can limit or shut down the output to ensure the stable operation of the system as a whole under self-powered conditions.

[0050] During normal operation of the bushing, the power acquisition module 10 continuously extracts micro-power energy from the end-screen displacement current, and supplies it to the modulation output module 20 after rectification and primary energy storage. This energy is first impedance-regulated by the impedance matching unit 21 to ensure optimal energy transfer conditions in the modulation output branch during operation. Subsequently, the power accumulation unit 22 further stores the energy. Based on this, the modulation output module 20 outputs a measurement signal to sample or monitor the bushing's operating voltage. Through this method, the modulation output module 20 achieves controlled output and voltage measurement based on energy accumulation even when the power of the end-screen displacement current is limited. This effectively avoids the impact of continuous operation on the end-screen potential distribution and significantly improves the reliability and adaptability of the system under long-term online monitoring conditions.

[0051] The modulation output module 20, through the coordinated operation of the impedance matching unit 21, the energy accumulation unit 22, and the control output unit 23, achieves effective management and utilization of the electrical signal on the bushing end screen side. This design not only overcomes the power supply problems existing in traditional methods but also significantly improves the safety and reliability of power equipment, reduces operation and maintenance costs, and demonstrates great application potential in the field of high-voltage transformer bushing condition monitoring. In this way, the present invention solves the problems of fixed parameter limitations and large external power supply interference in the prior art, providing a brand-new solution that enables the voltage monitoring device to operate autonomously for a long time without the need for external power supply intervention, which has important practical value and broad engineering application prospects.

[0052] In one embodiment, please refer to Figure 5 The adaptive compensation module 30 includes a voltage divider calculation unit 31, a compensation adjustment unit 32, and a status monitoring unit 33. The voltage divider calculation unit 31 is used to calculate the operating voltage based on the voltage sampling signal on the end screen side and the equivalent capacitance distribution of the bushing by combining a fixed proportional coefficient and a status correction term. The compensation adjustment unit 32 is used to dynamically update the compensation coefficient according to the real-time monitored operating status information and adjust the voltage divider capacitor using linear interpolation to correct the measurement deviation. The status monitoring unit 33 is used to monitor the working status of the adaptive compensation module 30 and the changes in bushing operating parameters, obtain status information, and feed the status information back to the compensation adjustment unit 32 for adjustment.

[0053] The voltage divider calculation unit 31 is connected to the signal acquisition terminal of the voltage monitoring device; wherein, the bushing is equivalent to a multi-layer capacitor series structure, and the voltage of the final screen V2 and the main voltage of the bushing V1 satisfy an approximate proportional relationship: The proportionality coefficient k0 is determined by the bushing structure parameters, the equivalent capacitance of the end screen, and the voltage divider network parameters. With the proportionality coefficient fixed, a state correction term is added. Where k0 is the factory-calibrated basic partial pressure coefficient; k1 is the compensation coefficient dynamically updated by the compensation adjustment unit 32.

[0054] In one embodiment, please refer to Figure 5 The compensation adjustment unit 32 is used to select and linearly interpolate the compensation coefficient from the pre-stored parameter table based on the calculation results of the voltage divider calculation unit 31 and the current operating status, so as to correct the measurement error caused by environmental or equipment changes, and feed the updated parameters back to the voltage divider calculation unit 31 for adjustment.

[0055] In one embodiment, please refer to Figure 5 The adaptive compensation module 30 also includes a control unit, which is connected to the voltage divider calculation unit 31, the compensation adjustment unit 32, and the status monitoring unit 33. The status monitoring unit 33 is used to monitor the working status of the adaptive compensation module 30 and the running status of the bushing based on the temperature sensor built into the control unit and the voltage divider capacitor in conjunction with the ADC channel.

[0056] In this embodiment, as Figure 5 As shown, the adaptive compensation module 30, as the core component of the voltage monitoring system based on the self-powered bushing end screen, not only undertakes the task of accurately measuring the operating voltage of the bushing, but also has the ability to dynamically adjust and monitor online for a long time. This module consists of a voltage divider calculation unit 31, a compensation adjustment unit 32, a status monitoring unit 33, and a control unit. Each part works closely together to ensure the accuracy and stability of the high-voltage transformer bushing voltage monitoring.

[0057] The voltage divider calculation unit 31 is the foundation for achieving accurate voltage measurement. It calculates the operating voltage by combining a fixed proportionality coefficient k0 and a state correction term k1. Here, the bushing is considered as a multi-layer capacitor series structure, and the relationship between the final screen voltage V2 and the bushing main voltage V1 is as follows: Wherein, k0 is the basic voltage divider coefficient determined based on the bushing structure parameters, the equivalent capacitance of the end screen, and the voltage divider network parameters; while k1 is the compensation coefficient dynamically updated by the compensation adjustment unit 32 according to the real-time operating status. This design allows for accurate calculation of the actual operating voltage of the bushing without changing its original electrical characteristics, greatly improving the accuracy of voltage monitoring. In addition, the voltage divider calculation unit 31 is connected to the signal acquisition terminal of the voltage monitoring device, ensuring timely data transmission and processing.

[0058] The compensation adjustment unit 32 is responsible for dynamically correcting the voltage measurement results based on the current operating status information. It selects appropriate compensation coefficients from a pre-stored parameter table and updates these coefficients using linear interpolation to correct measurement errors caused by factors such as changes in ambient temperature and drift in bushing medium parameters. The existence of the compensation adjustment unit 32 ensures that high voltage measurement accuracy is maintained even under complex operating conditions through continuous optimization of the compensation strategy. This method not only effectively addresses the challenges posed by environmental changes but also significantly reduces the impact of equipment aging on measurement accuracy.

[0059] The status monitoring unit 33 plays a crucial role, continuously monitoring the operating status of the adaptive compensation module 30 and the bushing's condition through its built-in temperature sensor, voltage divider capacitor, and ADC channel. This includes, but is not limited to, the stability of the voltage divider signal, power supply status, and changes in other key parameters. The collected status information is fed back to the compensation adjustment unit 32 in real time, allowing the latter to dynamically adjust the compensation strategy based on the latest operating conditions, thereby ensuring the system's stability and accuracy. This real-time monitoring mechanism greatly enhances the overall system's response speed and adaptability, enabling it to perform excellently in various operating environments.

[0060] The control unit, as the core of the entire adaptive compensation module 30, is responsible for coordinating data interaction and operational processes between various units. It not only incorporates necessary sensors and circuits but also integrates advanced algorithms to manage the entire compensation process, ensuring efficient collaboration among units according to a predetermined plan. In this way, the control unit effectively guarantees the overall system performance, achieving accurate measurement and feedback of bushing voltage. Furthermore, the control unit's design takes into account the practical needs of engineering applications, making the system highly applicable and worthy of widespread adoption.

[0061] Therefore, the adaptive compensation module 30 in this embodiment functions to dynamically correct and compensate the voltage division measurement results on the bushing end-screen side under the condition that the power acquisition module 10 provides self-power, thereby improving the measurement accuracy and stability of the voltage monitoring device under different operating conditions. The voltage division calculation unit 31 is connected to the signal acquisition terminal of the voltage monitoring device. The signal acquisition relies on the ADC module in conjunction with the MCU, employing a calculation method with a fixed proportional coefficient and a state correction term. This method calculates the bushing operating voltage based on the voltage signal acquired on the end-screen side, combined with the bushing's equivalent capacitance distribution and voltage division relationship. This calculation treats the bushing as an equivalent multi-layer capacitor series structure, with the end-screen voltage V2 and the bushing main voltage V1 satisfying an approximate proportional relationship. The proportional coefficient k0 is determined by the bushing structural parameters, the end-screen equivalent capacitance, and the voltage division network parameters. For this fixed proportional coefficient, this invention further adds a state correction term, where k0 is the factory-calibrated basic voltage division coefficient, and k1 is a compensation coefficient dynamically updated by the compensation adjustment unit 32. The compensation adjustment unit 32 is connected to the voltage divider calculation unit 31 and is used to adaptively correct the voltage measurement results based on the voltage divider calculation results and operating status information. This module pre-stores a set of compensation parameter tables. When the status monitoring unit 33 detects a change in operating status, it determines the current operating status interval, then reads the corresponding compensation coefficient, updates the voltage divider capacitor C using linear interpolation, and transmits the updated compensation coefficient to the voltage divider calculation unit 31. By introducing compensation coefficients or adjustment algorithms, the measurement deviation caused by changes in ambient temperature, bushing medium parameter drift, or changes in the end-screen energy extraction state is dynamically compensated, so that the output voltage signal remains within a predetermined accuracy range. The status monitoring unit 33 is connected to the voltage divider calculation unit 31 and the compensation adjustment unit 32 and is used to monitor the working status of the adaptive compensation module 30 and the bushing operating status. It mainly relies on the temperature sensor built into the control unit and the voltage divider capacitor C in conjunction with the ADC channel to obtain information on the stability of the voltage divider signal, the power supply status, and changes in key parameters, and feeds the status information back to the compensation adjustment unit 32 to assist in updating and adjusting the compensation parameters. During normal operation of the bushing, the power acquisition module 10 provides power to the voltage monitoring device and the adaptive compensation module 30. The voltage divider calculation unit 31 calculates the bushing operating voltage based on the voltage sampling signal of the end screen side and inputs the calculation result into the compensation adjustment unit 32. The compensation adjustment unit 32 adaptively corrects the voltage calculation result according to the operating status information fed back by the status monitoring unit 33 and outputs the final measured value. In this way, the adaptive compensation module 30 realizes dynamic compensation and correction of the bushing voltage measurement result under the condition of self-powered displacement current of the end screen, reduces the impact of changes in operating conditions on measurement accuracy, and improves the reliability and consistency of the voltage monitoring device under long-term online monitoring conditions.

[0062] In summary, the adaptive compensation module 30, through its innovative design concept and technical implementation, solves the accuracy problem inherent in traditional passive voltage divider detection methods and overcomes the interference issues caused by the need for external power supply in active voltage divider methods. It not only improves the accuracy and stability of the voltage monitoring device but also reduces the impact of changes in operating conditions on measurement accuracy, demonstrating its enormous application potential and technological advantages in the field of high-voltage transformer bushing condition monitoring. This method is not only suitable for condition monitoring and fault diagnosis of high-voltage transformer bushings but also shows broad application prospects in other application scenarios requiring long-term online voltage monitoring.

[0063] In this embodiment, the voltage monitoring device is connected to the power acquisition module to obtain the DC energy converted from the displacement current on the bushing's end screen side. It is also connected to the voltage divider calculation unit in the adaptive compensation module to receive voltage sampling signals from the end screen side and calculate the bushing operating voltage based on these signals.

[0064] The control unit is mainly integrated within the adaptive compensation module and is responsible for performing several key functions: With the help of the ADC (Analog-to-Digital Converter) module, the voltage signal is digitally processed and analyzed, thereby supporting the voltage divider calculation unit to calculate the bushing operating voltage.

[0065] The control compensation adjustment unit dynamically adjusts the compensation coefficient based on the data fed back from the status monitoring unit to ensure the accuracy and stability of the voltage division ratio.

[0066] The status monitoring unit relies on components such as the temperature sensor built into the MCU to monitor the system's operating status and provide feedback information to assist in updating and adjusting compensation parameters.

[0067] In this embodiment, self-powered operation is achieved by capturing the inherent displacement current of the end screen. Data exchange between the internal and external secondary sides is solely via optical fiber, completely eliminating the electrical connection between the high and low voltage sides. Even in the event of lightning strikes or operational overvoltages, there will be no "backlash," effectively ensuring the safety of the secondary equipment. This technical solution eliminates the need for external power supply equipment and matching shielded cables, significantly reducing the difficulty of insulation design and engineering costs. Regarding monitoring accuracy, the device in this embodiment achieves adaptive compensation adjustment of the voltage division ratio. While maintaining the physical stability of the voltage division signal on the end screen side, parameter compensation corrects voltage division ratio drift, avoiding the impact of active voltage regulation devices on the stability of the high-voltage side. Regardless of drastic fluctuations in ambient temperature or equipment aging, the voltage division ratio remains near its theoretical optimal value (with errors typically reduced to within 0.2%), ensuring that the equipment requires no manual offline calibration during long-term operation, thus achieving accurate and stable voltage measurement. In terms of engineering applicability, since the amplitude of the displacement current of the end screen is limited and the instantaneous power cannot meet the continuous power supply requirements, the device in this embodiment adopts a combination of multi-stage voltage multiplier rectification and energy storage capacitors to convert high-amplitude, low-current AC signals into energy that can be accumulated over time, thereby achieving usable power supply under low-power conditions. The device is connected to the end screen terminal of the bushing, making installation convenient and requiring no additional modifications. The grounding is reliable and stable, eliminating safety hazards caused by external connections. The adaptive compensation algorithm is applicable to high-voltage bushings of multiple voltage levels, demonstrating strong applicability in engineering applications.

[0068] To address the limitations of fixed parameters and significant external power supply interference in existing transformer bushing voltage monitoring systems, this embodiment proposes a complete solution. By constructing an adaptive compensation voltage monitoring system based on self-powered bushing end screen, and utilizing the end screen for power supply and control of the adaptive compensation monitoring module, long-term online voltage monitoring without external power connection is achieved. This significantly improves the safety, reliability, stability, and accuracy of the device, effectively eliminating the error effects of long-term online monitoring and the impact of device aging. Regarding the power supply method, this research breaks through the reliance on traditional long-distance external power transmission. By designing a power-harvesting device connected to the bushing end screen, the voltage monitoring system operates stably without external power supply through self-powered operation. This greatly avoids lightning surge backlash and electromagnetic interference introduced by long cables, and also maintains the integrity of the original insulation structure of the high-voltage equipment. Regarding voltage monitoring accuracy, this study proposes an adaptive compensation voltage divider mechanism. By comparing changes in voltage divider conditions and adjusting the compensation module, it reduces voltage divider ratio deviations under environmental and long-term monitoring conditions, ensuring long-term accurate and stable monitoring. This mechanism offers broader applicability and better economy in practical applications, with simplified operation and maintenance, demonstrating significant advantages. This embodiment, without introducing external power supply or altering the original electrical structure of the bushing's end screen, is the first to organically combine the limited extraction of the end screen displacement current, time-cumulative power supply, and the adaptive compensation voltage divider mechanism, constructing a high-voltage bushing voltage monitoring scheme capable of long-term online operation. This scheme exhibits significant advantages in safety, stability, and long-term accuracy maintenance, making it particularly suitable for condition monitoring scenarios of high-voltage and ultra-high-voltage bushings.

[0069] The device in this embodiment is designed to address the challenges of transformer bushing condition monitoring. Traditional voltage divider monitoring devices have significant limitations, making it difficult to balance voltage monitoring accuracy, anti-interference performance, and device stability. Therefore, this embodiment constructs an adaptive voltage divider system based on self-powered end-screen. By establishing a power supply and output module for the end-screen and utilizing the grounding current generated by the end-screen grounding, a self-powered design for the voltage divider device without external power supply is achieved, enabling long-term online autonomous operation. Based on this power supply module, the device in this embodiment is designed with an adaptive compensation module 30, which can adaptively adjust the voltage division ratio according to on-site testing requirements, ensuring the accuracy and stability of voltage monitoring and achieving accurate measurement and feedback of bushing voltage. The design of the self-powered module and the transmission module allows the device in this embodiment to operate without external power in actual bushing voltage monitoring scenarios, effectively improving accuracy and reducing related interference, demonstrating significant technical advantages and engineering application value.

[0070] In the specific implementation of the technical solution, the device in this embodiment constructs an adaptive compensation voltage monitoring system based on self-powered end screen of the bushing. It utilizes the power source of the end screen to control the adaptive compensation monitoring module, achieving long-term online voltage monitoring without external power connection. This solves the three major technical problems of traditional methods: low voltage monitoring accuracy, low device adaptability, and power supply interference. The technical advantages of this embodiment include self-powered operation using displacement current, eliminating the need to run power lines from the low-voltage end. This not only avoids lightning surge backlash and electromagnetic interference introduced by long cables but also maintains the integrity of the original insulation structure of the high-voltage equipment. Compared to the traditional end-screen voltage divider, whose accuracy is severely affected by environmental temperature drift and insulation aging, this solution optimizes the transition from fixed measurement to adaptive compensation, significantly improving accuracy. The device is integrated into a well-shielded end-screen box, and its self-powered characteristics make it unaffected by potential rise within the site, resulting in a clean waveform substrate and the ability to capture even weaker partial discharge characteristics.

[0071] The device in this embodiment aims to provide an adaptive compensation voltage monitoring technology based on self-powered high-voltage bushing end screen. Specifically, this technology involves a high-voltage bushing end screen voltage monitoring device with adaptive compensation function that relies on power drawn from the bushing end screen. The core technology utilizes the displacement current generated when the end screen is grounded. By acquiring this displacement current and powering the voltage divider device through a power supply module, no external power supply is required. While eliminating interference from external leads, a novel adaptive compensation voltage divider system is constructed through the adaptive compensation voltage divider module, enabling long-term adaptive voltage monitoring of the transformer's high-voltage bushing. This technology is mainly applied to the condition monitoring and fault diagnosis scenarios of high-voltage transformer bushings. It aims to solve the accuracy reduction of traditional passive voltage divider detection methods under long-term measurement conditions, and the problems of active voltage dividers requiring external power supply and being subject to high-frequency high-voltage interference. It can be integrated into the terminal block of the transformer's high-voltage bushing end screen, effectively achieving long-term autonomous voltage monitoring without external intervention, and preventing power equipment failures caused by bushing insulation deterioration.

[0072] The aforementioned adaptive compensation voltage divider device based on self-powered bushing end screen utilizes a power acquisition module 10 to obtain displacement current from the bushing end screen side for safe self-powering, converting AC signals into DC energy for subsequent use. Simultaneously, the device employs a modulation output module 20 to adjust the equivalent impedance according to load characteristics to optimize power conditions and store DC energy. When the energy storage meets requirements, it accurately outputs a measurement signal corresponding to the bushing operating voltage. Specifically, the adaptive compensation module 30 calculates the operating voltage based on the voltage sampling signal, dynamically updates the compensation coefficient to ensure the accuracy and stability of the voltage division ratio, monitors the system status in real time, and provides feedback information for adjusting compensation parameters. This method not only eliminates interference from external leads but also significantly improves the system's anti-interference capability and long-term operational reliability, making it particularly suitable for high-voltage and ultra-high-voltage bushing status monitoring scenarios. Through this design, high-precision monitoring and feedback of bushing voltage are achieved, maintaining excellent performance even under complex operating conditions.

[0073] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An adaptive compensation voltage divider device based on self-powered end screen of a bushing, characterized in that, include: Power acquisition module, modulation output module, and adaptive compensation module; The power acquisition module is used to safely acquire displacement current and voltage sampling signals from the bushing end screen side to power the voltage monitoring device, limit the current, use a clamping network to protect the circuit from overvoltage damage, and convert AC signals into DC energy. The modulation output module is used to adjust the equivalent impedance according to the characteristics of the downstream load to optimize the power conditions, store the DC energy from the power acquisition module, and output a measurement signal corresponding to the bushing operating voltage when the energy storage reaches the requirement. The adaptive compensation module is used to calculate the bushing operating voltage based on the voltage sampling signal of the power acquisition module, and dynamically update the compensation coefficient to ensure the accuracy and stability of the voltage division ratio, monitor the system operating status and provide feedback information for updating the compensation parameters.

2. The adaptive compensation voltage divider device based on self-powered end screen of the bushing as described in claim 1, characterized in that, The power acquisition module includes a signal acquisition unit, a safety overvoltage protection unit, and a rectification unit connected in sequence. The signal acquisition unit is used to extract displacement current and voltage sampling signals from the end screen side of the high-voltage bushing. The safety overvoltage protection unit is used to clamp and limit the displacement current. The rectification unit is used to rectify the clamped and limited AC current signal and convert it into DC energy.

3. The adaptive compensation voltage divider device based on self-powered end screen of the bushing as described in claim 2, characterized in that, The signal acquisition unit includes a series resistor and a coupling capacitor connected in sequence to ensure that the displacement current component is extracted without changing the original equivalent grounding characteristics of the bushing.

4. The adaptive compensation voltage divider device based on self-powered end screen of the bushing as described in claim 3, characterized in that, The safety overvoltage protection unit includes a clamping network; the rectifier unit includes a multi-stage voltage multiplier rectifier circuit and an energy storage capacitor connected in sequence, the clamping network is connected to the coupling capacitor; the multi-stage voltage multiplier rectifier circuit is connected to the clamping network; and the energy storage capacitor is connected to the modulation output module.

5. The adaptive compensation voltage divider device based on self-powered end screen of the bushing according to claim 4, characterized in that, The modulation output module includes an impedance matching unit, an energy accumulation unit, and a control output unit; the control output unit is connected to an output branch, and the impedance matching unit is used to adjust the equivalent impedance of the modulation output branch to ensure optimal energy transmission conditions without changing the electrical characteristics of the end screen. The power accumulation unit is used to further store and buffer the DC energy from the power acquisition module; The control output unit is used to monitor the energy storage status and drive the modulation output branch to generate a measurement signal corresponding to the bushing operating voltage when the energy is sufficient, while limiting or shutting down the output when the energy storage is insufficient.

6. The adaptive compensation voltage divider device based on self-powered end screen of the bushing according to claim 5, characterized in that, The impedance matching unit is used to adjust the equivalent impedance of the modulation output branch through a resistor-capacitor combination network.

7. The adaptive compensation voltage divider device based on self-powered end screen of the bushing according to claim 6, characterized in that, The adaptive compensation module includes a voltage divider calculation unit, a compensation adjustment unit, and a status monitoring unit. The voltage divider calculation unit calculates the operating voltage based on the voltage sampling signal from the end screen and the equivalent capacitance distribution of the bushing by combining a fixed proportional coefficient and a status correction term. The compensation adjustment unit dynamically updates the compensation coefficient based on real-time monitored operating status information and adjusts the voltage divider capacitor using linear interpolation to correct measurement deviations. The status monitoring unit monitors the operating status of the adaptive compensation module and changes in bushing operating parameters, acquires status information, and feeds this information back to the compensation adjustment unit for adjustment.

8. The adaptive compensation voltage divider device based on self-powered end screen of the bushing according to claim 7, characterized in that, The voltage divider calculation unit is connected to the signal acquisition terminal of the voltage monitoring device; wherein, the bushing is equivalent to a multi-layer capacitor series structure, and the voltage of the final screen V2 and the main voltage of the bushing V1 satisfy an approximate proportional relationship: The proportionality coefficient k0 is determined by the bushing structure parameters, the equivalent capacitance of the end screen, and the voltage divider network parameters. With the proportionality coefficient fixed, a state correction term is added. Where k0 is the factory-calibrated basic partial pressure coefficient; k1 is the compensation coefficient dynamically updated by the compensation adjustment unit.

9. The adaptive compensation voltage divider device based on self-powered end screen of the bushing as described in claim 8, characterized in that, The compensation adjustment unit is used to select and linearly interpolate the compensation coefficients from a pre-stored parameter table based on the calculation results of the voltage divider calculation unit and the current operating status, so as to correct the measurement error caused by environmental or equipment changes, and feed the updated parameters back to the voltage divider calculation unit for adjustment.

10. The adaptive compensation voltage divider device based on self-powering of the bushing end screen according to claim 9, characterized in that, The adaptive compensation module also includes a control unit, which is connected to the voltage divider calculation unit, the compensation adjustment unit, and the status monitoring unit. The status monitoring unit is used to monitor the working status of the adaptive compensation module and the operating status of the bushing based on the temperature sensor and voltage divider capacitor built into the control unit in conjunction with the ADC channel.

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