Non-intrusive voltage measurement device and design method

Abstract

The application relates to the technical field of voltage measurement, and discloses a non-intrusive voltage measurement device and a design method, which solve the problem that existing non-intrusive voltage measurement devices are easily affected in a harsh environment, thereby reducing measurement accuracy. The device comprises a metal shell, a sensor array provided with at least two electric field sensors and a voltage inversion module arranged in the metal shell, at least one hole array is arranged on the side wall of the metal shell, each hole array comprises at least two holes, the metal shell is electrically connected with a measured conductor in an installed state and forms an equipotential body, each electric field sensor is arranged corresponding to a hole in the hole array, and the sensing surface of the electric field sensor faces the corresponding hole; the voltage inversion module is electrically connected with each electric field sensor, is used for performing differential calculation on the output signals of the at least two electric field sensors, obtaining differential electric field data, and inversely calculating the voltage of the measured conductor according to the differential electric field data.

Description

Technical Field

[0001] This application relates to the field of voltage measurement technology, and in particular to a non-invasive voltage measurement device and its design method. Background Technology

[0002] With the continuous construction of new power systems and smart grids, the demand for monitoring the operating status of transmission lines, substation equipment and high-voltage busbars is constantly increasing. Among them, voltage parameters can directly reflect the operating conditions and fault characteristics of power equipment and are one of the key parameters in power system monitoring.

[0003] Currently, the design method in the power industry typically involves using voltage transformers connected to electrical equipment or transmission lines for invasive voltage measurement. This method suffers from poor frequency response and narrow bandwidth. Furthermore, the large size, high cost, complex insulation structure, and inconvenient installation of voltage transformers make it inconsistent with the trend of miniaturization and intelligentization in power measurement equipment.

[0004] To address this, a non-invasive voltage measurement scheme was proposed. While this non-invasive approach offers advantages such as avoiding direct contact with electrical equipment or transmission lines and reducing equipment size, it still requires the placement of an electric field sensor array around the conductor being measured. This presents challenges in practical applications due to the need for sensor array protection and fixation. Placing exposed electric field sensors directly around the conductor under test can easily damage them in harsh environments such as wind, rain, and lightning, severely impacting the stability and reliability of the measurement. Summary of the Invention

[0005] This application proposes a non-invasive voltage measurement device and design method, aiming to solve the problem that existing non-invasive voltage measurement devices are easily affected by harsh environments, thereby reducing measurement accuracy.

[0006] The first aspect of this application provides a non-invasive voltage measurement device, comprising: a metal housing, and a sensor array and a voltage inversion module disposed inside the metal housing, which are equipped with at least two electric field sensors; The metal casing has at least one array of holes on its sidewall, each array of holes including at least two holes; the metal casing is electrically connected to the conductor being measured in the installed state and forms an equipotential body. Each of the electric field sensors is configured to correspond to one of the holes in the hole array, and the sensing surface of the electric field sensor faces the corresponding hole; The voltage inversion module is electrically connected to each of the electric field sensors; The voltage inversion module acquires the output signals of each electric field sensor, performs differential calculations on the output signals of at least two electric field sensors to obtain differential electric field data, and inverts the voltage of the conductor under test based on the differential electric field data.

[0007] In one feasible embodiment of the first aspect, the non-invasive voltage measuring device further includes a metal bracket disposed at the location of the hole array and electrically connected to the inner sidewall of the metal housing by welding or screw connection, so that the sensor array, the metal bracket and the metal housing form an equipotential body.

[0008] In one feasible embodiment of the first aspect, an adjustment structure is provided on the metal support for fine-tuning the position and orientation of each electric field sensor in the sensor array.

[0009] In one feasible embodiment of the first aspect, it further includes: a metal partition disposed inside the metal housing and connected to the metal support to form a closed space for enclosing the sensor array.

[0010] In one feasible embodiment of the first aspect, the metal casing is cylindrical in shape and has a through hole at its bottom. The diameter of the through hole matches the outer diameter of the conductor being tested, so that the metal casing is fitted onto the outside of the conductor being tested after installation and forms an equipotential body with the conductor being tested.

[0011] In one feasible embodiment of the first aspect, it further includes: a metal clamp that simultaneously clamps the metal housing and the outer surface of the conductor under test, and the metal clamp is electrically connected to the metal housing so that the metal housing and the conductor under test form an equipotential body.

[0012] In one feasible embodiment of the first aspect, the different holes in the hole array have different apertures, and the distance between the sensing surface of the corresponding electric field sensor and the inner surface of the metal housing is the same. or, The holes in the hole array have the same aperture, and the distances between the sensing surface of the corresponding electric field sensor and the inner surface of the metal casing are different from each other.

[0013] In one feasible embodiment of the first aspect, the voltage inversion module is specifically used for: The output signals of all electric field sensors are processed pairwise to construct multiple sets of differential electric field data; Based on multiple sets of differential electric field data, the voltage of the conductor under test is obtained by inverting the nonlinear relationship between the differential electric field data and the voltage of the conductor under test.

[0014] In one feasible embodiment of the first aspect, the voltage inversion module is further configured to: An iterative optimization algorithm is used to update the voltage inversion parameters in the nonlinear relationship to improve the inversion accuracy.

[0015] A second aspect of this application provides a design method for the aforementioned non-invasive voltage measurement device, comprising: The first parameter of the conductor under test, the second parameter of the metal casing in the non-invasive voltage measuring device, and the performance parameters of the electric field sensor are obtained, wherein the metal casing is an equipotential body surrounding the conductor under test, and the side wall of the metal casing is provided with an opening through which the electric field passes. Based on the first parameter, the second parameter, and the performance parameter, an electric field simulation model is established that includes the conductor under test, the metal shell, and the opening. By adjusting the size of the opening and / or adjusting the distance between the sensing surface of the electric field sensor and the inner surface of the metal housing, the electric field intensity distribution on the sensing surface is calculated using the electric field simulation model. Based on the range of the electric field sensor and the electric field intensity distribution, determine a configuration scheme for at least two of the electric field sensors; Based on the configuration scheme, determine the actual size of the opening and / or the actual installation position of the electric field sensor; Based on the actual installation location and the actual size of the opening, adjust each electric field sensor in the non-invasive voltage measuring device to obtain the target voltage measuring device, and install it on the conductor to be measured.

[0016] The non-invasive voltage measurement device and design method provided in this application include a metal housing, and a sensor array with at least two electric field sensors, a metal bracket, and a voltage inversion module disposed inside the metal housing. At least one hole array is provided on the side wall of the metal housing, and each hole array includes at least two holes. The metal housing is electrically connected to the conductor under test in the installed state to form an equipotential body. Each electric field sensor is set to one hole in the hole array and is fixed by the metal bracket, with the sensing surface of the electric field sensor facing the corresponding hole. The voltage inversion module is electrically connected to each electric field sensor and is used to construct differential electric field data based on the output signals of at least two electric field sensors, and to invert the voltage of the conductor under test from the differential electric field data.

[0017] In this application, the electric field sensor is encapsulated in a metal shell, which effectively reduces the impact of environmental factors on the electric field sensor and improves the stability and reliability of the measuring device under complex working conditions. By constructing differential electric field data based on the output signals of each electric field sensor for voltage inversion, common-mode interference is effectively suppressed, improving the accuracy of non-invasive voltage measurement. The device provided in this application has a simple structure and is easy to install, which is conducive to online installation and engineering applications. Attached Figure Description

[0018] Figure 1 This is a structural block diagram of the non-invasive voltage measuring device in this application; Figure 2 This is a schematic diagram of the installation of the non-invasive voltage measuring device in this application; Figure 3 This is a schematic diagram of the internal structure of the non-invasive voltage measuring device in this application; Figure 4 This is another schematic diagram illustrating the installation of the non-invasive voltage measuring device in this application; Figure 5 This is a schematic diagram of one embodiment of the design method in this application; Figure 6 This is a schematic diagram of the first structural design of the metal support in this application; Figure 7 This is a schematic diagram of the second structure of the metal support in this application; Figure 8 This is a schematic diagram of the third structure of the metal support in this application; Figure 9 This is a schematic diagram of the fourth structure of the metal support in this application; Figure 10 This is a schematic diagram of the support layout for the array sensor in this application, where the distances from each probe to the surface are not equal. Figure 11 This is a schematic diagram of the fifth structure of the metal support in this application; Figure 12 This is a schematic diagram of the voltage inversion iteration process in this application. Detailed Implementation

[0019] The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in a sequence other than that illustrated or described herein.

[0020] Furthermore, the terms “comprising” or “having” and any variations thereof are intended to cover non-exclusive inclusion, for example, including a system, product, or device is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such products or devices.

[0021] In traditional non-invasive voltage measurement techniques, the electric field sensor array is directly exposed to the environment surrounding the conductor being measured, making it susceptible to physical damage under harsh weather conditions. External factors such as wind, rain, or lightning can damage the sensor structure or distort the signal, thus affecting the continuity and accuracy of voltage measurements. Furthermore, the lack of effective protection mechanisms in the mounting methods of the sensor array leads to a decline in reliability of the measurement system over long-term operation. This manifests as signal anomalies caused by sensor surface contamination, mechanical damage, or electromagnetic interference, thereby reducing the real-time performance and stability of power system condition monitoring.

[0022] For example, in the scenario of monitoring outdoor high-voltage busbars in substations, electric field sensor arrays are deployed near the busbars to collect electric field data. During strong winds, rainwater or dust particles adhering to the sensor surface are impacted by the wind, causing contamination or mechanical damage to the sensor's sensing surface. Simultaneously, electromagnetic interference caused by lightning can lead to abnormal fluctuations in the sensor's output signal. Consequently, voltage measurement data experiences intermittent interruptions or deviations, affecting the real-time performance of power system status monitoring. Specifically, the sensor array, lacking protective structures, cannot maintain normal operation under windy, rainy, or thunderstorm conditions, resulting in incomplete voltage parameter acquisition.

[0023] To address the aforementioned problems, this application provides a non-invasive voltage measurement device comprising a metal housing, a sensor array, and other fixed structures. The metal housing has openings, the size of which, along with the distance from the surface of each electric field sensor in the sensor array to the inner surface of the metal housing, determines the electric field strength at the sensor placement location. The specific magnitude is determined through simulation calculations. This structure not only reduces the risk of damage to electronic equipment from wind, rain, dust, and other factors, but also provides good shielding against external electromagnetic interference, reducing some of the interference from the external electromagnetic environment on electric field measurements. Furthermore, using the difference between two electric field sensors for inversion calculations during data processing can suppress common-mode interference.

[0024] like Figure 1 The diagram shown is a structural block diagram of a non-invasive voltage measurement device proposed in an embodiment of this application. The non-invasive voltage measurement device includes: a metal housing 100, and a sensor array 200 and a voltage inversion module 400 disposed inside the metal housing 100, which are equipped with at least two electric field sensors 210.

[0025] It should be noted that the metal housing 100 is a conductive enclosure used to encapsulate and protect the internal components. During installation, the metal housing 100 forms an electrical connection with the conductor being measured 1000, thereby constituting an equipotential body, providing a stable reference potential for the internal electric field sensor 210, and shielding against external environmental interference. In practical applications, the metal housing 100 can be made of various conductive materials, such as aluminum alloy or stainless steel, and its shape can be designed as square, circular, or irregularly shaped according to the actual application scenario to adapt to the installation requirements of different conductors being measured 1000. For example, when measuring a conductor with a circular cross-section, the metal housing 100 can be designed with a structure having an arc-shaped inner wall. In practical applications, the metal housing 100 can specifically consist of two halves connected by a rotating fixed hinge C.

[0026] The aperture array 110 is actually a collection of multiple apertures disposed on the sidewall of the metal casing 100. These apertures allow the electric field generated by the conductor under test 1000 to penetrate the metal casing 100 and modulate the electric field, so that the internal electric field sensor 210 can sense the differentiated electric field signals.

[0027] The sensor array 200 consists of at least two electric field sensors 210. These electric field sensors 210 are used to sense the electric field strength around the conductor 1000 being measured and convert the sensed electric field information into an electrical signal output. In practical applications, these electric field sensors 210 can be of various types, such as capacitive sensors or photoelectric sensors.

[0028] The electric field sensor 210 is used to sense the local electric field strength and output a corresponding electrical signal. In this embodiment, multiple electric field sensors 210 are arranged at different spatial positions within the metal housing 100 to obtain electric field data at different spatial points.

[0029] The voltage inversion module 400 processes the output signal of the electric field sensor 210 and calculates the voltage of the measured conductor 1000. This module uses a specific algorithm to convert the acquired electric field data into actual voltage values. In practical applications, the voltage inversion module 400 is an integrated circuit board that integrates functional units such as signal acquisition, data processing, and voltage calculation.

[0030] In this embodiment, as Figure 2 and 3 As shown, the metal housing 100 has at least one hole array 110 on its sidewall, and each hole array 110 includes at least two holes; the metal housing 100 is electrically connected to the conductor 1000 under test in the installed state and forms an equipotential body.

[0031] In practical applications, the holes in the hole array 110 can be formed by drilling, punching, or laser cutting. The shape of the holes can be circular, square, or slit-shaped, and their size and arrangement can be designed according to the requirements of electric field modulation. For example, multiple holes can be evenly distributed along the circumference of the metal casing 100, or holes can be concentrated in a specific area.

[0032] In its installed state, the metal casing 100 is electrically connected to the conductor 1000 under test, forming an equipotential body. This electrical connection can be achieved through direct contact, such as by tightly fitting the metal casing 100 onto the conductor 1000 under test. A good conductive path can be ensured using auxiliary materials such as conductive pads or conductive rubber A. By forming an equipotential body, stable boundary conditions can be provided for electric field measurements, and external electromagnetic interference can be effectively shielded.

[0033] In this embodiment, the non-invasive voltage measuring device further includes a metal bracket 300, which is disposed at the position of the hole array 110 and is electrically connected to the inner sidewall of the metal housing 100 by welding or screw connection, so that the sensor array 200, the metal bracket 300 and the metal housing 100 form an equipotential body.

[0034] It should be noted that the metal bracket 300 is used to fix each electric field sensor 210 in the sensor array 200. The metal bracket 300 is actually a conductive structure that, while ensuring the stability of the position and orientation of the electric field sensor 210 inside the metal housing 100, forms an equipotential body with the metal housing 100. Specifically, it is composed of a conductive metal plate or a metal frame and is fixed to the metal housing 100 by mechanical connection.

[0035] The electric field sensor 210 can be fixed by screws, clips, or adhesive to ensure its position and orientation stability. The sensing surface faces the corresponding hole, allowing the electric field sensor 210 to directly sense the electric field signal modulated by the hole. For example, the electric field sensor 210 can be mounted on a metal bracket 300, and then the metal bracket 300 can be fixed inside the metal housing 100, so that the sensing surface of each sensor 210 faces a hole.

[0036] The voltage inversion module 400 is electrically connected to each of the electric field sensors 210, and is used to acquire the output signal of each electric field sensor 210, perform differential calculation on the output signals of at least two electric field sensors 210 to obtain differential electric field data, and invert the voltage of the conductor 1000 under test based on the differential electric field data.

[0037] Specifically, the voltage inversion module 400 can be electrically connected to the electric field sensor 210 via wires or a flexible circuit board. The output signal can be acquired by converting the analog signal to a digital signal using an analog-to-digital converter (ADC). Differential electric field data can be constructed by performing simple subtraction or weighted averaging and subtraction on the output signals of different electric field sensors 210. The voltage of the measured conductor 1000 can be inverted using a pre-established mathematical model, such as the relationship curve between electric field and voltage obtained through finite element simulation or experimental calibration, and by performing table lookup or interpolation calculations on the differential electric field data.

[0038] For example, when it is necessary to perform a non-invasive measurement of the voltage of a high-voltage transmission line (the conductor under test 1000), the non-invasive voltage measuring device of this embodiment is first installed on the conductor under test 1000. The metal housing 100 of the device is fitted or attached to the outer surface of the conductor under test 1000, and a good electrical connection is ensured between the metal housing 100 and the conductor under test 1000 through direct contact or conductive connectors, thereby making the two constitute a unified equipotential body.

[0039] Inside the metal casing 100, multiple electric field sensors 210 in the sensor array 200 are precisely fixed by a metal bracket 300. The sensing surfaces of these electric field sensors 210 each face a hole in a pre-set hole array 110 on the side wall of the metal casing 100. When the conductor 1000 being measured is charged, an electric field is generated around it. Since the metal casing 100 and the conductor 1000 being measured form an equipotential body, and the metal casing 100 is provided with the hole array 110, the electric field generated by the conductor 1000 being measured will pass through these holes and form a modulated local electric field in the vicinity of the holes.

[0040] Due to the presence of the aperture array 110 and the relative positions of each electric field sensor 210 to its corresponding aperture, different electric field sensors 210 will sense electric field signals with varying intensities. For example, a sensor closer to the center of the aperture may sense a stronger electric field, while a sensor farther from the center may sense a weaker electric field. These differentiated electric field signals are converted into electrical signals by each electric field sensor 210 and transmitted to the voltage inversion module 400.

[0041] After receiving output signals from at least two electric field sensors 210, the voltage inversion module 400 processes them. Specifically, the module performs differential calculations based on these output signals to obtain differential electric field data. For example, the output signals of two adjacent electric field sensors 210 can be subtracted to eliminate common-mode interference in the environment and highlight the difference signal caused by the voltage of the measured conductor 1000. Subsequently, the voltage inversion module 400 performs inversion calculations on the constructed differential electric field data according to a pre-established nonlinear relationship model between the differential electric field data and the voltage of the measured conductor 1000. This model can be obtained through theoretical analysis, simulation, or experimental calibration. Through inversion calculations, the accurate voltage value of the measured conductor 1000 is finally obtained.

[0042] Thus, the device provides physical protection and electromagnetic shielding for the internal sensor through the metal casing 100, ensures the stability of the sensor position through the metal bracket 300, effectively modulates the electric field through the aperture array 110, and achieves non-invasive, stable, and reliable measurement of the voltage of the conductor 1000 under test through differential processing and inversion algorithm of the voltage inversion module 400.

[0043] In summary, the non-invasive voltage-capacity measurement device provided in this application, by introducing a metal casing 100, provides robust physical protection and effective electromagnetic shielding for the internal sensor array 200, improving the device's operational reliability in harsh environments such as wind, rain, and lightning. Simultaneously, the metal casing 100 and the conductor under test 1000 form an equipotential body, providing a stable reference potential and boundary conditions for electric field measurement, further ensuring measurement accuracy.

[0044] This application further proposes that the metal bracket 300 is electrically fixed to the metal housing 100 by welding or screw connection, so that the sensor array 200, the metal bracket 300 and the metal housing 100 constitute a unified equipotential body.

[0045] Specifically, the conductive fixation between the metal bracket 300 and the metal shell 100 can be achieved in various ways. For example, welding is a connection method that uses heating, pressure, or both to form a strong bond between metal atoms, such as spot welding, arc welding, or laser welding, to form a fusion connection on the contact surface between the metal bracket 300 and the metal shell 100, ensuring a low-resistance electrical path between them.

[0046] Another method is screw connection, which connects two or more components together with threaded fasteners. For example, screw holes are reserved on the metal bracket 300 and the metal housing 100, and the connection is fastened with conductive screws, nuts and washers. To ensure good conductivity, the connection surfaces can be cleaned or conductive washers can be used.

[0047] The core function of these two connection methods is to ensure a stable and reliable electrical connection between the metal support 300 and the metal housing 100, thereby making them equal in potential. Through this conductive fixation, the sensor array 200, the metal support 300, and the metal housing 100 are electrically at the same potential, i.e., forming a unified equipotential body. This is crucial for electric field measurement, as the electric field sensor 210 typically requires a stable reference potential to accurately measure the electric field strength.

[0048] By electrically fixing the metal bracket 300 to the metal housing 100, the metal bracket 300 also acquires the same potential as the metal housing 100. Since the metal housing 100 is electrically connected to the conductor 1000 under test in the installed state, forming an equipotential body, the metal bracket 300 is also at the same potential as the conductor 1000 under test. Given that the electric field sensor 210 in the sensor array 200 is fixed via the metal bracket 300, and its ground plane or housing is typically connected to the mounting structure, the reference potential of the sensor array 200 is also consistent with that of the metal bracket 300. Therefore, the sensor array 200, the metal bracket 300, and the metal housing 100 together constitute a unified equipotential body, which is at the same potential as the conductor 1000 under test. This unified equipotential body provides a stable and well-defined potential reference for the electric field sensor 210, ensuring that the electric field sensor 210 operates in a defined electric field environment and can accurately sense changes in the electric field modulated by the aperture array 110 without being affected by potential drift or inconsistency of internal components. This provides a reliable foundation for subsequent differential electric field data construction and voltage inversion.

[0049] For example, the metal housing 100 can be made of stainless steel or aluminum alloy, which have good conductivity and mechanical strength. The metal bracket 300 can also be made of a conductive metal, such as brass or aluminum. During device assembly, the bottom edge of the metal bracket 300 can be fused to the inner wall of the metal housing 100 using argon arc welding to form a continuous conductive path. Alternatively, holes can be pre-drilled on the mounting surface of the metal bracket 300 and aligned with corresponding threaded holes on the metal housing 100, then fastened using nickel-plated copper screws, ensuring good electrical contact between the screws and the metal bracket 300 and the metal housing 100. The electric field sensor 210 in the sensor array 200 typically has a metal housing or grounding pin, which can be in direct contact with the metal bracket 300 or connected via wires, thereby aligning the reference potential of the sensor array 200 with that of the metal bracket 300.

[0050] Through the above technical solution, the sensor array 200, metal bracket 300, and metal housing 100 are formed into a unified equipotential body and electrically connected to the conductor 1000 under test, thereby providing a stable and definite potential reference for the electric field sensor 210. This effectively avoids measurement errors introduced by potential drift or inconsistency of internal components, ensuring that the electric field sensor 210 can accurately sense changes in the electric field around the conductor 1000 under test. As a result, the acquired differential electric field data has higher reliability and consistency, significantly improving the accuracy and stability of the voltage inversion module 400 in inverting the voltage of the conductor 1000 under test, thus optimizing the overall performance of the non-invasive voltage measurement device.

[0051] This application further proposes an adjustment structure on the aforementioned metal bracket 300, which is a combination of threaded holes and screws, allowing for fine-tuning of the position and orientation of each electric field sensor in the sensor array by adjusting the combination.

[0052] Specifically, the adjustment structure can be a mechanical foot or an electromechanical device, its function being to adjust and fix the relative position and attitude of the electric field sensor 210, ensuring that the electric field sensor 210 can be accurately positioned and oriented to meet measurement accuracy requirements. For example, this adjustment structure uses the cooperation of screws and nuts to achieve translational adjustment of the sensor in the X, Y, and Z directions, and uses a ball joint or universal joint structure to achieve fine adjustment of attitude (pitch, yaw, roll). In addition, this adjustment structure can also be a sliding groove mechanism, in which a slider moves within a preset track, and a locking screw is used to fix the position, while a rotatable mounting base is used to achieve attitude adjustment.

[0053] In this embodiment, the adjustment structure is actually integrated on the metal bracket 300 and connected to each electric field sensor 210 in the sensor array 200 via screws or other adjustable means. After the electric field sensors 210 are installed, the position and orientation of each electric field sensor 210 can be finely adjusted by adjusting the screws corresponding to each electric field sensor 210. This adjustment capability can match the electric field to the subtle differences between different measured objects, and can also be used to ensure that the sensing surface of each electric field sensor 210 is accurately aligned with the corresponding hole in the hole array 110, while maintaining a preset distance and angle relationship. Since electric field measurement is highly sensitive to the position and orientation of the sensor, especially for differential electric field measurement, any small deviation can introduce significant errors. The existence of the adjustment structure allows for independent or coordinated fine-tuning of each electric field sensor 210 during device assembly or on-site calibration, thereby optimizing its sensing effect on the electric field around the measured conductor 1000. By precisely adjusting the sensor, measurement deviations caused by installation errors can be minimized, ensuring the accuracy and consistency of the output signals from each electric field sensor 210. This improves the reliability of constructing differential electric field data and ultimately enhances the accuracy of voltage inversion. This precise fixing and fine-tuning mechanism solves the problem of insufficient sensor installation accuracy under simple fixing methods, providing a reliable foundation for the subsequent high-precision voltage calculation based on differential electric field data by the voltage inversion module 400.

[0054] For example, the metal bracket 300 can be designed with multiple mounting holes or grooves, each corresponding to an electric field sensor 210. The adjustment structure can include a sensor mounting base for fixing the electric field sensor 210, which can be integrally formed with the electric field sensor 210 or connected by screws. The mounting base can be provided with adjusting screws that pass through threaded holes in the metal bracket 300. By screwing in or out the adjusting screws, the electric field sensor 210 can be finely adjusted in a direction perpendicular to the plane of the metal bracket 300. Simultaneously, the mounting base and the metal bracket 300 can be connected by a ball joint or universal joint and secured by a lock nut or clamping mechanism, thereby allowing the electric field sensor 210 to be finely adjusted in pitch and yaw attitude within a certain angle range. After the position and attitude adjustment is completed, the electric field sensor 210 is securely fixed to the metal bracket 300 by tightening the lock nut or additional fixing screws.

[0055] By setting an adjustment structure on the metal bracket 300, the position and orientation of each electric field sensor 210 in the sensor array 200 can be precisely fine-tuned. This solves the problem of difficulty in ensuring the installation accuracy of the electric field sensor 210 under traditional fixing methods, ensuring that the sensing surface of each electric field sensor 210 can be accurately aligned with the corresponding hole in the hole array 110, and maintaining the preset distance and angle relationship. Therefore, the measurement deviation caused by installation errors can be minimized, ensuring the accuracy and consistency of the output signal of each electric field sensor 210, thereby improving the reliability of differential electric field data, and ultimately significantly improving the accuracy of voltage inversion of the measured conductor 1000.

[0056] This application further proposes that the above-mentioned non-invasive voltage measuring device also includes a metal partition 500, which is located inside the metal housing 100 and connected to the metal support 300 to form a closed space for enclosing the sensor array 200.

[0057] It should be noted that the metal partition 500 is a plate-shaped structure made of conductive material, and the plate-shaped structure is provided with an arc-shaped groove that matches the object being measured. The main function of the metal partition 500 is to provide physical isolation and electromagnetic shielding, that is, to isolate and shield the sensor array 200 from other circuit modules in the device, so as to avoid mutual interference between the two.

[0058] The metal partition 500 can be made of a metal material with good conductivity and mechanical strength, such as stainless steel, aluminum alloy, or copper, or a non-metallic material with a conductive coating, to ensure its conductive shielding performance. The metal partition 500 is disposed inside the metal housing 100. This arrangement ensures that the metal partition 500 works in conjunction with the metal housing 100 to form an integrated shielding structure, enclosing the sensor array 200 and effectively blocking external interference. The metal partition 500 can be designed to fit tightly against the inner wall of the metal housing 100 or fixed to a specific position inside the metal housing 100 via slots, limiting structures, etc., or it can be directly fixed to the inner surface of the metal housing 100 by welding, riveting, or screws. The metal partition 500 is connected to the metal support 300. This connection allows the metal partition 500 and the metal support 300 to form a continuous conductive path, further enhancing the overall shielding effect on the sensor array 200 and contributing to the formation of a unified equipotential body. The metal partition 500 can be mechanically and electrically connected to the metal bracket 300 by means of screws, rivets, or welding. Alternatively, it can be designed to overlap or snap-fit ​​with the edge of the metal bracket 300 to ensure good conductive contact. This structure forms a closed space for enclosing the sensor array 200. This closed space is the core function for protecting the sensor array 200, isolating it from the external environment to effectively prevent physical corrosion from dust, moisture, corrosive gases, etc., and providing additional electromagnetic shielding. The closed space can be formed by the metal partition 500, the metal housing 100, the metal bracket 300, and other possible structural components, ensuring the airtightness of the space. Alternatively, the metal partition 500 can be designed as a box-shaped structure and then connected and sealed to corresponding parts of the metal bracket 300 and the metal housing 100.

[0059] The solution of this application introduces a metal partition 500 into a non-invasive voltage measurement device, placing it inside a metal housing 100 and connecting it to a metal support 300, thereby forming a closed space for enclosing the sensor array 200. When the metal housing 100 is electrically connected to the conductor 1000 under test in the installed state, forming an equipotential body, the metal partition 500, metal support 300, sensor array 200, and metal housing 100 together constitute a unified equipotential body because the metal partition 500 is connected to the metal support 300, and the metal support 300 is usually also electrically fixed to the metal housing 100. This equipotential closed space can effectively isolate the sensor array 200 from the external environment. Specifically, this closed space can provide a physical barrier, preventing dust, moisture, corrosive gases, and other substances from entering, thereby protecting the electric field sensor 210 from physical damage and environmental corrosion. At the same time, since the metal partition 500 is conductive, it, together with the metal housing 100 and metal support 300, forms a Faraday cage effect shielding structure. This shielding structure effectively attenuates or blocks interference from external electromagnetic fields on the sensor array 200, ensuring that the electric field sensor 210 only senses the electric field signal of the conductor 1000 under test modulated by the aperture array 110, thereby improving the purity and accuracy of the measurement signal. This overall shielding and protection mechanism enables the sensor array 200 to operate stably and reliably in complex and variable environments, thus ensuring that the voltage inversion module 400 can obtain the voltage of the conductor 1000 under test based on more accurate electric field data.

[0060] The following is a specific example illustrating this. The metal partition 500 can be made of 1mm thick aluminum alloy sheet, and its shape is designed to match the inner contour of the metal housing 100, with openings for the sensor array 200 and cables to pass through. The metal partition 500 is securely connected to the edge flange of the metal bracket 300 using multiple M3 stainless steel screws, with evenly spaced screws to ensure good electrical contact and mechanical stability. Conductive rubber gaskets or conductive liners can be placed at the contact edges between the metal partition 500 and the metal housing 100 to further enhance sealing and electromagnetic shielding, ensuring a completely enclosed space. The sensor array 200 is fixed to the metal bracket 300 and is completely located within the enclosed space formed by the metal partition 500, the metal bracket 300, and the metal housing 100.

[0061] By introducing a metal partition 500 into the non-invasive voltage measurement device and connecting it to the metal housing 100 and metal support 300 to form a closed space, the sensor array 200 can be effectively isolated from the external environment. This significantly enhances the physical protection of the electric field sensor 210, preventing it from being corroded and damaged by environmental factors such as dust, moisture, and corrosive gases, thereby extending the device's service life and reducing maintenance costs. Simultaneously, this closed space also provides additional electromagnetic shielding, effectively suppressing the influence of external electromagnetic interference on the signal of the electric field sensor 210, and improving the purity and stability of the electric field signal acquisition. This enables the voltage inversion module 400 to perform voltage inversion based on more accurate and reliable electric field data, thereby significantly improving the measurement accuracy and reliability of the non-invasive voltage measurement device, especially in harsh or complex industrial environments.

[0062] In this regard, this application further proposes that the above-mentioned non-invasive voltage measurement device also includes an energy harvesting module, a communication module, and an environmental parameter acquisition module connected to the voltage inversion module 400. The energy harvesting module, the communication module, and the environmental parameter acquisition module are located inside the metal casing 100 and outside the enclosed space.

[0063] The energy harvesting module is designed to provide a continuous power supply for the non-invasive voltage measurement device. The concept involves harvesting energy from the external environment and converting it into electrical energy to power various electronic components within the device, including the voltage inversion module 400. Possible implementations include, but are not limited to: harvesting energy from the electromagnetic field surrounding the conductor 1000 being measured via an induction coil (electromagnetic induction energy harvesting); converting light energy into electrical energy via a solar panel (solar energy harvesting); converting mechanical vibration energy into electrical energy via a vibration sensor (vibration energy harvesting); or converting ambient temperature difference into electrical energy via the thermoelectric effect (thermoelectric energy harvesting).

[0064] The communication module is used to enable data exchange between the non-invasive voltage measurement device and external systems. The concept is to transmit the voltage data and other operating status information processed by the voltage inversion module 400 to a remote monitoring center or local terminal, while also receiving control commands from external systems. Possible implementation methods include, but are not limited to: using wireless communication technologies, such as Wi-Fi, Bluetooth, LoRa, NB-IoT, or 5G cellular network technologies, to achieve wireless data transmission; or using wired communication technologies, such as RS485, Ethernet, or fiber optic communication, to transmit data through physical lines.

[0065] The environmental parameter acquisition module is used to monitor key physical parameters of the environment in which the non-invasive voltage measurement device operates in real time. The concept involves integrating various sensors to acquire information such as temperature, humidity, vibration, and pressure of the device's operating environment. This information is crucial for assessing the device's operating status, predicting potential faults, and performing environmental compensation. Possible implementation methods include, but are not limited to: integrating temperature and humidity sensors to monitor environmental temperature and humidity; integrating acceleration or vibration sensors to monitor device vibration; or integrating pressure sensors to monitor ambient air pressure.

[0066] The aforementioned energy harvesting module, communication module, and environmental parameter acquisition module are located inside the metal casing 100 but outside the enclosed space. This arrangement means that these modules are installed inside the metal casing 100 but physically isolated from the enclosed space used to protect the sensor array 200. This is significant because the metal casing 100 provides overall mechanical protection and electromagnetic shielding, while preventing the heat, electromagnetic interference, or physical vibration generated by these auxiliary modules during operation from affecting the highly sensitive electric field sensor 210 within the enclosed space, thus ensuring the accuracy and stability of the core measurement functions. Simultaneously, this layout facilitates the maintenance or upgrading of these auxiliary modules without opening or affecting the enclosed space.

[0067] This application's solution introduces an energy harvesting module, a communication module, and an environmental parameter acquisition module into the aforementioned non-invasive voltage measurement device, cleverly placing them inside the metal casing 100 but outside the enclosed space, thus constructing a more complete and adaptable voltage measurement system. Specifically, the energy harvesting module is responsible for continuously harvesting energy from the external environment and converting it into stable electrical energy, providing a reliable power supply to the entire device, including the voltage inversion module 400, ensuring the device can operate autonomously for extended periods. The communication module is electrically connected to the voltage inversion module 400, transmitting the voltage data of the measured conductor 1000 calculated by the voltage inversion module 400, along with the device's own operating status information, to a remote monitoring system or a local data receiver via a preset communication protocol, achieving real-time uploading and remote monitoring of measurement data. Simultaneously, the environmental parameter acquisition module continuously monitors key parameters of the device's environment, such as temperature, humidity, and vibration, and provides this environmental data to the voltage inversion module 400 for data compensation, or transmits it along with the device via the communication module, providing crucial information for device operating status assessment and fault diagnosis. This layout allows the core sensor array 200 and voltage inversion module 400 to remain effectively protected within the enclosed space formed by the metal partition 500, free from external environmental interference and potential interference from the auxiliary modules themselves, thus ensuring the accuracy and stability of voltage measurement. Simultaneously, the external placement of the auxiliary modules ensures that maintenance or upgrades will not affect the sealing and integrity of the core measurement components. In this way, the device not only accurately measures voltage but also achieves self-powered operation, remote data transmission, and environmental adaptability, greatly enhancing its practicality and reliability.

[0068] In one specific implementation, the energy harvesting module can be an electromagnetic induction energy harvesting unit integrating an induction coil and a rectifier and voltage regulator circuit. This unit can capture energy from the alternating electromagnetic field surrounding the conductor 1000 being measured and convert it into DC power required by the device. The communication module can be a low-power wide-area network (LPWAN) module, such as a LoRa module, which wirelessly communicates with a remote gateway via an antenna, periodically transmitting the voltage measurement results output by the voltage inversion module 400 and the data collected by the environmental parameter acquisition module. The environmental parameter acquisition module can be an integrated digital temperature and humidity sensor and a triaxial accelerometer, used to monitor the temperature, humidity, and potential vibrations of the internal environment of the device in real time. These modules are all securely mounted on the inner wall of the metal casing 100, but outside the enclosed space defined by the metal partition 500, and are electrically connected to the voltage inversion module 400 via flexible ribbon cables or shielded cables to ensure signal transmission stability and anti-interference capability.

[0069] Through the above technical solutions, the non-invasive voltage measurement device achieves self-powered operation, remote communication, and environmental adaptability. The introduction of the power harvesting module allows the device to operate independently for extended periods without an external power cord, significantly reducing installation and maintenance costs and improving deployment flexibility. The communication module enables real-time remote transmission of measurement data, allowing users to obtain voltage information of the measured conductor 1000 anytime, anywhere, greatly improving monitoring efficiency and response speed. The environmental parameter acquisition module provides real-time data on the device's operating environment, facilitating accurate environmental compensation of measurement results and providing crucial information for device health monitoring and fault early warning. More importantly, these auxiliary modules are cleverly placed inside the metal casing 100 but outside the enclosed space, ensuring the realization of auxiliary functions while effectively isolating them from potential electromagnetic interference and thermal effects on the core measurement components (sensor array 200). This significantly enhances the overall functionality and practicality of the device without sacrificing measurement accuracy, enabling it to better adapt to various complex industrial environments.

[0070] In other embodiments, this application proposes a non-invasive voltage measuring device, wherein the metal housing 100 is cylindrical in shape, and a through hole 120 is provided at the bottom. The diameter of the through hole 120 matches the outer diameter of the conductor 100 being measured, so that the metal housing 100, after installation, fits over the outside of the conductor 1000 and forms an equipotential body with the conductor 1000. To ensure conductive connection between the metal housing 100 and the conductor 1000, conductive rubber A is provided at the location of the through hole 120. The conductive rubber A is locked in place by a fastener and a fixing bolt B, ensuring tight electrical contact with the conductor 1000.

[0071] The metal casing 100 is cylindrical in shape. This design allows the casing to surround the conductor 1000 being measured, creating a uniform electric field environment around it, which is beneficial for the electric field sensor 210. The cylindrical structure also provides good mechanical strength and stability, and is easy to manufacture and install. For example, it can be made from a single piece of metal tubing or formed by welding rolled plates. A through-hole 120 is provided at the bottom, which is a key structural feature of the metal casing 100 for housing the conductor 1000. This through-hole 120 allows the conductor 1000 to pass directly through the bottom of the metal casing 100, enabling coaxial mounting of the measuring device and the conductor 1000. The through-hole 120 can be precision machined using a CNC machine tool to ensure dimensional accuracy and surface finish, or it can be integrally formed using a casting process. The aperture of the through-hole 120 matches the outer diameter of the conductor 1000 under test. This matching aperture is fundamental to ensuring that the metal housing 100 can be stably fitted onto the outside of the conductor 1000 and form a good electrical connection. A matching aperture reduces installation gaps, improves installation tightness, and thus enhances the reliability of electrical contact. This matching can be achieved by pre-measuring the outer diameter of the conductor 1000 and then customizing or selecting a metal housing 100 with a corresponding aperture, or by providing an adjustable bushing or clamping mechanism on the inner wall of the through-hole 120 to accommodate conductor outer diameters within a certain range. This ensures that the metal housing 100, after installation, fits onto the outside of the conductor 1000 and forms an equipotential body with it. This installation method is one of the core prerequisites for achieving non-invasive voltage measurement. By fitting the metal housing 100 onto the outside of the conductor 1000 and ensuring an electrical connection, the metal housing 100 and the conductor 1000 can be at the same potential, forming an equipotential body. This not only simplifies the implementation of equipotential connections but also provides a stable reference potential for the internal electric field sensor 210, enabling accurate sensing of electric field changes around the conductor 1000 under test. Electrical connections can be achieved through direct contact, conductive pads, conductive adhesive, or metal clamps.

[0072] The solution of this application designs the metal casing 100 as an integral cylinder, with a through-hole 120 at its bottom that matches the outer diameter of the conductor 1000 under test. This allows the non-invasive voltage measuring device to be mounted on the conductor 1000 under test in a sleeve-like manner. During installation, the conductor 1000 can pass directly through the through-hole 120, allowing the metal casing 100 to be sleeved over the outside of the conductor 1000. Because the diameter of the through-hole 120 matches the outer diameter of the conductor 1000, this ensures tight contact between the metal casing 100 and the conductor 1000, thereby reliably establishing an electrical connection and forming a unified equipotential body. This sleeve-like mounting method not only simplifies the installation process and avoids complex connection operations, but also provides a stable and uniform electric field environment for the internal sensor array 200 through physical tight enclosure. In this equipotential structure, each electric field sensor 210 in the sensor array 200 senses the electric field around the conductor 1000 under test through the aperture array 110. The voltage inversion module 400 can accurately invert the voltage of the conductor 1000 under test based on these sensed signals, thereby effectively solving the problems of poor contact and complex installation that may exist in the traditional equipotential connection method, and improving the stability and reliability of the measurement.

[0073] In practical applications, the metal housing 100 can be integrally formed into a cylindrical structure from stainless steel, with an outer diameter of approximately 100 mm and an inner diameter of approximately 90 mm. A through-hole 120 with a diameter of 30 mm is formed at the center of the bottom of the metal housing 100 using CNC machining. The diameter of this through-hole 120 is designed to match the outer diameter of common power cables (e.g., with an outer diameter of 28 mm to 32 mm). During installation, the non-invasive voltage measuring device is axially inserted from one end of the conductor 1000 being measured, allowing the conductor 1000 to pass through the through-hole 120 at the bottom of the metal housing 100 until the metal housing 100 is stably fitted over the outside of the conductor 1000 being measured. To ensure good electrical contact between the metal housing 100 and the conductor under test 1000, conductive elastic pads can be provided on the inner wall of the through hole 120 or at the bottom edge of the metal housing 100, or the metal housing 100 can be fastened to the conductor under test 1000 by external metal clamps (e.g., spring clamps or bolt clamps), thereby forming a reliable equipotential body between the two.

[0074] Through the above technical solution, the metal casing 100 is designed as an integral cylinder and has a through hole 120 that matches the outer diameter of the conductor 1000 being measured, allowing the measuring device to be mounted on the conductor 1000 in a sleeve-like manner. This mounting method greatly simplifies the installation process and improves installation efficiency and convenience. Simultaneously, the tight sleeve ensures a reliable electrical connection between the metal casing 100 and the conductor 1000 being measured, effectively solving the problem of poor contact that may occur during the formation of the equipotential body. This provides a stable measurement reference for the internal electric field sensor 210, improving the accuracy and reliability of voltage measurement. Furthermore, the cylindrical structure and sleeve mounting method also enhance the mechanical stability of the device, making it less prone to loosening or displacement in the operating environment.

[0075] This application further proposes that the non-invasive voltage measuring device also includes a metal clamp 600, which simultaneously clamps the outer surfaces of the metal housing 100 and the conductor 1000 being measured, and the metal clamp 600 is electrically connected to the metal housing 100 so that the metal housing 100 and the conductor 1000 being measured form an equipotential body, such as... Figure 4 As shown.

[0076] The metal clamp 600 is a mechanical device used to fix and connect two or more components. It is primarily made of conductive material to ensure that an electrical path is established while clamping. The metal clamp 600 can be a spring clamp, achieving clamping and electrical contact through the elastic force of the spring; or a bolt-fastening clamp, achieving clamping and electrical contact through the tightening force of the bolt; or a lever clamp or a snap-fit ​​clamp. The metal clamp 600 simultaneously clamps the outer surfaces of the metal housing 100 and the conductor 1000 being measured, aiming to ensure that the metal clamp 600 can simultaneously apply force to both the metal housing 100 and the conductor 1000, thereby establishing a stable mechanical connection and electrical contact between them. This clamping method avoids potential contact problems or loosening issues that may occur with individual fixing, improving the reliability and stability of the connection. For example, the clamp can be designed as a U-shaped or C-shaped structure, with its two ends contacting and clamping the metal housing 100 and the conductor 1000 under test, respectively; or the clamp can include adjustable clamping arms to accommodate metal housings 100 and conductors 1000 of different sizes. Furthermore, the metal clamp 600 is electrically connected to the metal housing 100, ensuring that the metal clamp 600 itself becomes part of the equipotential body of the metal housing 100, or serves as a bridge for the electrical connection between the metal housing 100 and the conductor 1000 under test. This electrical connection can be formed by direct contact between the metal clamp 600 and the conductive surface of the metal housing 100, or by providing conductive pads or conductive coatings on the contact surface, or by fixing it to the metal housing 100 with conductive fasteners such as bolts or rivets. The ultimate goal of the above technical means is to make the metal housing 100 and the conductor 1000 under test form an equipotential body, which is the basis for the normal operation of the entire device. By ensuring that the two form an equipotential body, the potential difference can be eliminated, enabling the electric field sensor 210 to accurately sense the electric field distribution and provide accurate raw data for voltage inversion.

[0077] The solution presented in this application effectively solves the problems of reliable electrical connection and equipotential formation between the metal housing 100 and the conductor under test 1000 by introducing a metal clamp 600. Specifically, the metal clamp 600 is designed to simultaneously clamp the outer surfaces of both the metal housing 100 and the conductor under test 1000. This dual clamping mechanism ensures a tight mechanical contact and a stable electrical path between the metal clamp 600 and both. Since the metal clamp 600 itself is conductive and electrically connected to the metal housing 100, when the metal clamp 600 simultaneously clamps both the metal housing 100 and the conductor under test 1000, it establishes a low-impedance electrical bridge between them. This allows the metal housing 100 and the conductor under test 1000 to quickly reach the same potential, thereby forming a unified equipotential body. Based on the formation of this equipotential body, the array of holes 110 on the sidewall of the metal casing 100 can precisely modulate the electric field around the conductor 1000 being measured, enabling each electric field sensor 210 in the sensor array 200 to sense different electric field intensities. The voltage inversion module 400 then accurately inverts the voltage of the conductor 1000 based on these differentiated electric field signals, by constructing differential electric field data and combining it with a preset nonlinear relationship. This reliable equipotential body connection achieved through the metal clamp 600 provides a stable measurement reference for the entire non-invasive voltage measurement device, significantly improving the accuracy and reliability of the measurement results.

[0078] In one specific implementation, the metal clamp 600 can employ a spring clamp structure made of highly conductive stainless steel or copper alloy. The spring clamp 600 has two opposing clamping arms, the inner surfaces of which can be machined into an arc shape to better conform to the outer surfaces of the circular or near-circular metal housing 100 and the conductor 1000 under test. One clamping arm is bolted to the metal housing 100 to ensure reliable electrical connection. The other clamping arm directly clamps the conductor 1000 under test using the preload of a spring. During installation, the operator simply opens the spring clamp 600, places it over the metal housing 100 and the conductor 1000, and then releases it; the spring force will then tightly clamp the two together. This design not only achieves an electrical connection between the metal housing 100 and the conductor 1000 under test, forming an equipotential body, but also offers simple and quick installation, suitable for rapid on-site deployment.

[0079] By introducing the aforementioned technical solution, a metal clamp 600 is used to simultaneously clamp the outer surfaces of the metal housing 100 and the conductor 1000 being measured, and is electrically connected to the metal housing 100. This non-invasive voltage measurement device ensures a stable and reliable electrical connection between the metal housing 100 and the conductor 1000 being measured, thereby effectively forming an equipotential body. This solves the problems of poor contact or unstable equipotential body formation that may exist in traditional installation methods, significantly improving the accuracy of the electric field sensed by the electric field sensor 210, and thus ensuring the accuracy and reliability of the voltage inversion module 400 inverting the voltage of the conductor 1000 being measured.

[0080] This application further proposes that different holes in the hole array 110 have different apertures, and the distance between the sensing surface of the corresponding electric field sensor 210 and the inner surface of the metal housing 100 is the same; or, the holes in the hole array 110 have the same aperture, and the distance between the sensing surface of the corresponding electric field sensor 210 and the inner surface of the metal housing 100 is different from each other.

[0081] The different holes in the hole array 110 have different apertures, meaning that the openings on the metal casing 100 used to expose the sensing surface of the electric field sensor 210 have different sizes. This can be achieved by directly machining holes of different sizes on the metal casing 100, for example, using laser cutting or CNC milling; or by installing bushings or annular structures with different inner diameters on standard-sized holes to form different apertures. Changing the aperture affects the distribution and density of electric field lines passing through the holes, thereby modulating the electric field strength sensed by the electric field sensor 210. The distance between the sensing surface of the corresponding electric field sensor 210 and the inner surface of the metal casing 100 is the same, meaning that the vertical distance from the sensing surface of each electric field sensor 210 to the inner wall of the metal casing 100 where its corresponding hole is located remains consistent. This can be achieved by precisely designing the structure of the metal bracket 300 to ensure that the distance between the sensing surfaces of all electric field sensors 210 and the inner surface of the metal housing 100 is consistent when fixing each electric field sensor 210; alternatively, by providing an adjustable mounting mechanism on the metal bracket 300, such as a threaded adjustment mechanism or shims, the position of each electric field sensor 210 can be finely adjusted to maintain an equidistant distance between its sensing surface and the inner surface of the metal housing 100. Maintaining the same distance helps control a variable in electric field modulation, making the influence of different apertures on the electric field strength more prominent and controllable.

[0082] Alternatively, the holes in the hole array 110 have the same aperture, meaning that all the holes on the metal housing 100 used to expose the sensing surface of the electric field sensor 210 have identical opening sizes. This can be achieved by mass production or molding to create holes of uniform size on the metal housing 100; alternatively, standardized hole bushings or inserts can be used to ensure that the effective aperture of all holes is consistent. The distances between the sensing surfaces of the corresponding electric field sensors 210 and the inner surface of the metal housing 100 are different, meaning that the vertical distance from the sensing surface of each electric field sensor 210 to the inner wall of the metal housing 100 where its corresponding hole is located is different. This can be achieved by designing the metal bracket 300 to preset different installation depths when fixing each electric field sensor 210, thus creating different distances; or by configuring shims of different thicknesses or pillars of different lengths on the metal bracket 300 for each electric field sensor 210 to achieve distance differentiation. Different distances will cause changes in the electric field intensity sensed by the electric field sensor 210, resulting in differentiated electric field signals even with the same aperture.

[0083] The non-invasive voltage measurement device of this application generates an electric field around the conductor 1000 after the metal casing 100 is electrically connected to the conductor 1000 to form an equipotential body. The aperture array 110 on the metal casing 100 modulates this electric field, causing electric field lines to pass through the apertures and enter the interior of the metal casing 100, where they are sensed by the electric field sensor 210. To ensure that each electric field sensor 210 can sense sufficiently differentiated electric field strengths, this application provides two optimized electric field modulation design schemes. The first scheme is to design different apertures in the aperture array 110 with different aperture diameters, while ensuring that the distance between the sensing surface of the corresponding electric field sensor 210 and the inner surface of the metal casing 100 remains the same. In this configuration, due to the difference in aperture size, even if the distance between the sensor and the inner surface of the casing is the same, the distribution and density of electric field lines passing through different apertures will be different, resulting in significant differences in the electric field strength sensed by each electric field sensor 210. This differentiated electric field signal provides a rich and controllable foundation for the voltage inversion module 400 to construct differential electric field data. A second approach is to maintain the same aperture size in the aperture array 110, but make the distances between the sensing surfaces of the corresponding electric field sensors 210 and the inner surface of the metal housing 100 different. In this configuration, although the aperture size is consistent, the electric field lines attenuate or diffuse during propagation due to the different distances between the sensor sensing surfaces and the apertures, resulting in sensors closer to the apertures typically sensing a stronger electric field than those farther away. This difference in distance can also effectively modulate the electric field, making the signals output by each electric field sensor 210 distinguishably different. Regardless of the design used, by introducing differences in aperture size or distance, it is possible to ensure that each electric field sensor 210 senses a significantly different electric field strength. The voltage inversion module 400 receives these differentiated output signals and constructs differential electric field data based on these signals. This differentiated data contains rich information about the voltage of the conductor 1000 under test, enabling the voltage inversion module 400 to more accurately and robustly invert the voltage of the conductor 1000 under test.

[0084] In one specific implementation, a non-invasive voltage measuring device may include two electric field sensors 210. In a first case, the aperture array 110 on the metal housing 100 may include two apertures, one with a diameter of 5 mm and the other with a diameter of 8 mm. Both apertures are circular. Simultaneously, the sensing surfaces of both electric field sensors 210 are fixed by a metal bracket 300, maintaining a distance of 10 mm from the inner surface of the metal housing 100. For example, the metal bracket 300 may be designed with two mounting bases of different sizes to accommodate different aperture layouts, while ensuring that the vertical distance from the sensor sensing surface to the inner surface of the housing is consistent. In a second case, the aperture array 110 on the metal housing 100 may include two apertures, both with a diameter of 6 mm. However, through the adjustment structure of the metal bracket 300, the sensing surface of the first electric field sensor 210 can be fixed at a position 8 mm from the inner surface of the metal housing 100, while the sensing surface of the second electric field sensor 210 is fixed at a position 12 mm from the inner surface of the metal housing 100. The metal bracket 300 can achieve this distance difference using adjustable threaded posts or support posts of varying heights. In both configurations, the electric field sensor 210 can be an electro-optic sensor based on the Pockels effect, or a miniature electric field sensor based on MEMS technology. The voltage inversion module 400 can be a microcontroller with an integrated digital signal processor (DSP) for performing signal acquisition, differential processing, and voltage inversion algorithms.

[0085] By employing the aforementioned technical solutions, and through differentiated design of the aperture size of the aperture array 110, or differentiated design of the distance between the sensing surface of the electric field sensor 210 and the inner surface of the metal casing 100, the electric field around the conductor 1000 under test can be effectively modulated, resulting in significant and controllable differences in the electric field intensity sensed by each electric field sensor 210. This differentiated electric field signal provides the foundation for the voltage inversion module 400 to construct differential electric field data with a high signal-to-noise ratio, thereby significantly improving the accuracy and robustness of voltage inversion. Especially in complex electric field environments, this design enhances the device's sensitivity to changes in the electric field and effectively suppresses common-mode interference, enabling the non-invasive voltage measurement device to more accurately measure the voltage of the conductor 1000 under test, thus improving the reliability and applicability of the measurement.

[0086] In some embodiments described above in this application, a scheme is proposed to invert the voltage of the conductor 1000 under test by acquiring the output signal of the electric field sensor 210 and constructing differential electric field data. However, in practical applications, the relationship between the electric field signal and the voltage of the conductor 1000 under test may not be a simple linear relationship, and single or limited differential electric field data may not be sufficient to accurately and robustly reflect this complex nonlinear relationship, thereby affecting the accuracy and reliability of voltage measurement.

[0087] In this regard, this application further proposes a voltage inversion module 400 specifically used for: performing pairwise differential processing on the output signals of all electric field sensors 210 to construct multiple sets of differential electric field data; and inverting the voltage of the measured conductor 1000 based on the multiple sets of differential electric field data and the nonlinear relationship between the differential electric field data and the voltage of the measured conductor 1000.

[0088] Specifically, constructing multiple sets of differential electric field data involves pairwise differential processing of the output signals of all electric field sensors 210. This means that after the voltage inversion module 400 receives the output signals of all electric field sensors 210 in the device, it generates new data points by calculating the difference between the output signals of any two electric field sensors 210. This differential processing can effectively suppress common-mode noise and environmental interference, improving the signal-to-noise ratio. By systematically differential processing all possible sensor pairs, richer and more comprehensive electric field distribution information can be obtained than with a single differential pair, which helps to more accurately characterize the electric field state around the conductor 1000 under test. For example, if there are N electric field sensors 210, C(N,2) sets of differential data can be generated. These differential data can form a differential vector or matrix as input for subsequent inversion. Alternatively, multiple sets of differential data can be generated by differentially processing the signal of each electric field sensor 210 with the signal of a preset reference electric field sensor 210.

[0089] Based on multiple sets of differential electric field data, the voltage of the measured conductor 1000 is inverted by combining the nonlinear relationship between the differential electric field data and the voltage of the measured conductor 1000. This means that after acquiring multiple sets of differential electric field data, the voltage inversion module 400 uses a pre-established model that describes the complex nonlinear mapping relationship between the differential electric field data and the voltage of the measured conductor 1000 to calculate the voltage value of the measured conductor 1000. This nonlinear relationship model can be modeled using machine learning algorithms, such as neural networks and support vector machine regression. Before the device is put into use, multiple sets of differential electric field data and corresponding real voltage values ​​can be collected under different voltage and environmental conditions through experiments or simulations, and a nonlinear model can be trained using these data. During actual measurement, the voltage inversion module 400 inputs the real-time acquired multiple sets of differential electric field data into the trained model, and the model outputs the voltage of the measured conductor 1000. As another implementation method, this relationship can also be described by establishing a set of nonlinear equations based on a physical model. For example, the response of the electric field sensor 210 under different voltages can be simulated using finite element analysis or the boundary element method, and the nonlinear functional relationship between the differential electric field data and the voltage can be derived from it. When the voltage inversion module 400 is running, it uses these nonlinear functional relationships to invert the voltage of the conductor 1000 under test from multiple sets of differential electric field data through iterative solution or table lookup method.

[0090] The solution in this application utilizes a specific configuration of the metal casing 100, the aperture array 110, and the electric field sensors 210 to enable different electric field sensors 210 to sense varying electric field strengths. After receiving the output signals from all the electric field sensors 210, the voltage inversion module 400 performs pairwise differential processing on these signals to construct multiple sets of differential electric field data. These multiple sets of differential electric field data provide richer and more comprehensive electric field distribution information than single differential data, enabling more precise capture of subtle changes in the electric field around the measured conductor 1000. Given the potential nonlinear relationship between the electric field data and the voltage of the measured conductor 1000, the voltage inversion module 400 further performs inversion calculations on these multiple sets of differential electric field data based on a pre-established nonlinear relationship model. This nonlinear inversion method can more accurately map complex electric field distributions to the actual voltage of the measured conductor 1000, thereby overcoming errors that may arise from simple linear models. In this way, the solution of this application can make full use of the information of all electric field sensors 210 and perform voltage inversion through a more accurate nonlinear model, which significantly improves the accuracy and robustness of voltage measurement.

[0091] Assume a non-invasive voltage measurement device has four electric field sensors 210, labeled E1, E2, E3, and E4. After the voltage inversion module 400 receives the output signals from these four electric field sensors 210, it can perform pairwise differential processing to construct multiple sets of differential electric field data. For example, the following six sets of differential data can be calculated: D1=E1-E2, D2=E1-E3, D3=E1-E4, D4=E2-E3, D5=E2-E4, D6=E3-E4. These D1 to D6 constitute multiple sets of differential electric field data. Before the device is put into actual measurement, a detailed calibration process can be performed. For example, the device is installed on the conductor 1000 with a known voltage, and the corresponding D1 to D6 data are collected under different voltage values ​​(such as 0V, 100V, 200V, etc.) and different environmental conditions (such as simulating different temperatures and humidity). This calibration data can be used to train a multilayer perceptron (MLP) neural network model. The input layer of this neural network can receive six sets of differential electric field data, D1 to D6, while the output layer outputs the voltage value of the measured conductor 1000. The neural network is trained using a backpropagation algorithm to learn the nonlinear mapping relationship between the differential electric field data and the voltage. During actual measurement, the voltage inversion module 400 acquires the output signal of the electric field sensor 210 in real time, calculates D1 to D6, and then inputs this differential data into the pre-trained neural network model. Based on the nonlinear relationship it has learned, the neural network model immediately outputs the current voltage value of the measured conductor 1000.

[0092] By employing the aforementioned technical solution, pairwise differential processing is performed on the output signals of all electric field sensors 210 to construct multiple sets of differential electric field data. This provides more comprehensive and richer electric field information and effectively suppresses noise and interference. Based on this, inversion is performed by combining the nonlinear relationship between the differential electric field data and the voltage of the measured conductor 1000. This allows for a more accurate capture of the complex mapping relationship between electric field and voltage, significantly improving the accuracy and reliability of non-invasive voltage measurement. This enables the device to provide stable and accurate measurement results under various complex operating conditions.

[0093] Based on the non-invasive voltage measurement device provided above, this application further proposes a design method, such as... Figure 5 As shown, the method includes the following steps: 510. Obtain the first parameter of the conductor under test, the second parameter of the metal casing in the non-invasive voltage measuring device, and the performance parameters of the electric field sensor; It should be noted that the metal casing is an equipotential body surrounding the conductor under test, and the side wall of the metal casing is provided with an opening through which the power field passes.

[0094] The first parameters of the conductor under test include the conductor's diameter (or radius), the expected installation height to ground (h), and the voltage level to be measured (V). These parameters define the basic properties of the external electric field source.

[0095] The second parameter of the metal casing mainly refers to the geometry and dimensions of the pre-selected or planned metal casing. In a preferred embodiment, the casing is cylindrical, and its radius (R) and height (H) need to be determined. The function of the casing is to connect with the conductor under test to form an equipotential shield.

[0096] The performance parameters of an electric field sensor are the range of the selected electric field sensor (which can be capacitive, photoelectric, field-milled, or MEMS type, etc.), that is, the range of electric field intensity that it can linearly and accurately measure (e.g., 0 to E_max kV / m).

[0097] The three parameters mentioned above can be input by engineers into design software or calculation models based on site survey data, equipment technical manuals, or design specifications.

[0098] In practical applications, the metal casing is cylindrical in shape, with a through hole on its bottom surface for the conductor being measured to pass through. The diameter of the through hole matches the outer diameter of the conductor being measured, so that the measuring device forms an electrically equipotential body with the conductor being measured after installation.

[0099] In one feasible implementation, the model of the conductor under test and its corresponding diameter and voltage level information are first read from the design database or user input interface; then, a preset standard metal casing model library is read, or the geometric dimensions of the casing to be used are manually entered.

[0100] 520. Based on the first parameter, the second parameter, and the performance parameters, establish an electric field simulation model that includes the conductor under test, the metal shell, and the opening; Specifically, computer-aided engineering (CAE) software, such as ANSYS Maxwell and COMSOL Multiphysics, can be used to construct three-dimensional electrostatic or quasi-electrostatic field simulation models. In these models, the conductor under test, the metal casing (set as the conductor boundary), and the opening structure are precisely modeled. By setting material properties, boundary conditions (such as applied voltage to the conductor under test and zero potential at ground level), and mesh generation, a mathematical model capable of calculating the electric field distribution near the opening and on the sensor's sensing surface is established. The core of this model is simulating the "leakage" effect of the electric field generated by the opening on the metal casing (equipotential body) on the conductor under test.

[0101] In this embodiment, step 520 can be specifically implemented through the following steps: First, a three-dimensional geometric model is established in the simulation software based on the acquired parameters; then, electrical excitation and boundary conditions are applied to the model, adaptive mesh generation is performed, and finite element analysis calculations are executed. The above two steps can be completed using the solver of the simulation software, solving the Poisson equation through numerical calculation to obtain the potential and electric field intensity distribution cloud maps in space, particularly inside the opening and at the sensor sensing surface.

[0102] In practical applications, based on the above parameters, three-dimensional electrostatic or quasi-electrostatic field simulation models are established using electromagnetic field simulation software (such as ANSYS Maxwell, COMSOL Multiphysics, etc.). The establishment of the model includes the following key elements: Geometric modeling: Precisely constructing the geometric structure including the conductor under test, a cylindrical metal shell (set as the ideal conductor boundary), and pre-defined openings (hole array) on the sidewalls of the shell. For example, simulating the shell fitting onto the conductor through a bottom through-hole, or achieving equipotential connection through metal clamps (hoops).

[0103] Condition settings: Set the potential of the conductor to be measured to the voltage V, and set the ground plane or infinity to zero potential. The potential of the metal casing is forced to be equal to that of the conductor to be measured (i.e., the potentials are both V).

[0104] Model Purpose: This model is used to simulate how the electric field generated by the conductor being measured "leaks" into the interior of the metal casing (equipotential body) through the opening, and to calculate the electric field intensity distribution at a specific location inside the opening (i.e., where the future sensor sensing surface is located).

[0105] 530. By adjusting the size of the opening and / or adjusting the distance between the sensing surface of the electric field sensor and the inner surface of the metal casing, the electric field intensity distribution on the sensing surface is calculated using an electric field simulation model. Specifically, by adjusting the size of the opening and / or the distance between the sensing surface of the electric field sensor and the inner surface of the metal casing, the electric field intensity distribution on the sensing surface is calculated using the electric field simulation model. This step is the core of the design optimization. The opening size (aperture) and the distance between the sensor sensing surface and the inner surface of the casing are two key controllable variables affecting the sensor's induced electric field intensity. Engineers can use parametric scanning to change these variables in the simulation model (e.g., the aperture changes from 1mm to 10mm in a certain step, or the distance changes from 2mm to 20mm in a certain step), and repeatedly run the simulation to calculate the electric field intensity at the center point or average of the sensor sensing surface for each combination of parameters. This yields a function curve or data table showing the electric field intensity as a function of the aperture or distance.

[0106] In this embodiment, step 530 can be implemented through the following steps: firstly adjust the size of the opening, for example, first keep the distance between the sensing surface of all electric field sensors in the simulation model and the inner surface of the metal shell the same preset value; then, set multiple different opening diameters in the simulation software for parametric scanning, calculate and record the electric field intensity at each sensing surface position under each diameter, and generate electric field distribution data.

[0107] Furthermore, step 530 can also prioritize adjusting the distance between the sensing surface of the electric field sensor and the inner surface of the metal casing; for example, firstly, all openings in the simulation model are kept to have the same aperture; then, multiple different sensor sensing surface positions (i.e., different distance values) are set in the simulation software for parametric scanning, and the electric field intensity at each sensing surface position under each distance is calculated and recorded to generate electric field distribution data.

[0108] In practical applications, this step is the core of design optimization, aiming to find the key structural parameters that enable the sensor to obtain an ideal electric field signal through simulation. Two equivalent and interchangeable design approaches exist and must be implemented in simulation: Implementation Method A (Adjusting the opening size): The distance (r) between the sensing surface of all electric field sensors and the inner surface of the metal casing is set to be the same. Then, the aperture (a) of different openings is systematically changed in the simulation model. The simulation is run for each aperture combination scheme, and the electric field intensity (E) value on the sensing surface behind each opening is calculated and recorded. Through parameter scanning, the electric field distribution cloud map and data curve can be obtained, clarifying the influence of aperture change on the induced electric field: the larger the aperture, the weaker the shielding effect, and the stronger the induced electric field.

[0109] Implementation Method B (Adjusting Sensor Distance): The aperture (a) of all openings on the metal casing is set to be the same. Then, the distance (r) between the sensing surface of different sensors and the inner surface of the casing is systematically varied in the simulation model. The simulation is run for each distance combination scheme, and the electric field intensity value (E) on the corresponding sensing surface is calculated and recorded. Through parameter scanning, the electric field distribution cloud map and data curve can be obtained, clarifying the influence of distance changes on the induced electric field: the closer the distance, the stronger the induced electric field.

[0110] 540. Based on the range and electric field intensity distribution of the electric field sensor, determine the configuration scheme of at least two electric field sensors; Specifically, based on the range of the electric field sensors and the electric field intensity distribution, a configuration scheme for at least two of the electric field sensors is determined. This step is a decision-making and selection process. Based on the electric field intensity distribution data calculated in step S3, the designer needs to ensure that, under the selected parameters, the electric field intensity on the sensing surface of each sensor is within its range to avoid sensor saturation or insufficient sensitivity. Furthermore, the goal is to obtain sufficiently different electric field readings from at least two sensors. Therefore, the configuration scheme needs to select specific parameter combinations (e.g., aperture A1 and distance D1 for sensor 1, and aperture A2 and distance D2 for sensor 2) such that the electric field values ​​E1 and E2 measured by the two sensors differ as much as possible within the allowable range. A larger difference helps suppress common-mode interference in subsequent differential calculations and provides more significant characteristic inputs for nonlinear inversion.

[0111] In practical applications, based on the large amount of simulation data obtained in step 530 (the functional relationship between electric field strength E and aperture a and / or distance r), optimization is performed to determine the final sensor configuration scheme. The selection must meet two core criteria: Range matching criterion: The induced electric field intensity E corresponding to the selected parameters (a, r) ​​for each sensor must be within the range of that electric field sensor, preferably operating in a range with good linearity, to avoid saturation or insufficient sensitivity.

[0112] Signal Differentiation Criterion: Under the premise of satisfying Criterion 1, different parameter combinations should be selected for at least two sensors (e.g., different apertures or different distances) so that there is as large a difference as possible between the electric field values ​​E1, E2, ..., En they sense. This difference is the basis for subsequent differential calculations to suppress common-mode interference (such as distant electromagnetic interference, ground potential fluctuations) and to construct effective inversion data.

[0113] The configuration scheme also includes determining the number (n) and layout of the sensor array, such as triangular, circular, or square arrays, as well as the specific aperture a_i and / or distance r_i for each sensor.

[0114] 550. Based on the configuration scheme, determine the actual size of the opening and / or the actual installation position of the electric field sensor; Specifically, based on the configuration scheme, the actual size of the opening and / or the actual installation position of the electric field sensor are determined. This step transforms the simulation optimization results into specific, manufacturable engineering design drawings and production instructions. For example, if the configuration scheme determines the use of two openings with diameters of 5mm and 8mm respectively, and the distance between the sensor sensing surface and the inner surface of the housing is 10mm for both, then the diameter and center position of these two holes need to be clearly marked on the machining drawings of the metal housing. Simultaneously, a corresponding sensor bracket (metal bracket) needs to be designed to ensure that the sensor can be precisely fixed at a position 10mm from the inner surface of the housing, with its sensing surface directly facing the center of the opening.

[0115] 560. Based on the actual installation location and the actual size of the opening, adjust each electric field sensor in the non-invasive voltage measuring device to obtain the target voltage measuring device, and install it on the conductor to be measured.

[0116] Specifically, based on the actual installation location and the actual size of the opening, the non-invasive voltage measuring device is assembled and installed on the conductor under test. This step is the physical implementation stage. According to the design drawings determined in step 550, the metal casing and opening are processed, and a metal bracket is fabricated or adjusted. The electric field sensor is installed on the metal bracket according to the determined position and orientation, ensuring reliable electrical connection. The sensor array, voltage inversion module, and other internal components are assembled into the metal casing. Finally, according to the size of the conductor under test, a suitable installation method is adopted, such as fitting through a bottom through-hole and filling with conductive silicone, or using a metal clamp for fixation; the entire device is installed on the conductor under test, ensuring a stable equipotential connection between the metal casing and the conductor under test.

[0117] Among them, determining the actual size of the opening: according to the optimal aperture a_i corresponding to each sensor in the configuration scheme, an array of holes is machined on the side wall of the metal shell.

[0118] Determine the actual installation location of the sensors: Design and fabricate a metal bracket for fixing the sensor array. On the bracket, precisely set the mounting slots or threaded holes for the sensors according to the optimal distance r_i corresponding to each sensor in the configuration scheme. The bracket itself should be reliably electrically connected to the inner wall of the housing by welding or screws. Furthermore, adjustment structures (such as elongated holes or fine-tuning screws) can be designed on the bracket to facilitate final position and orientation fine-tuning during on-site installation.

[0119] Determine the overall installation interface: Based on the diameter of the conductor being measured, finally determine the diameter of the through hole at the bottom of the metal casing, or select the specifications of the matching metal clamp (clamp).

[0120] The non-intrusive voltage measuring device provided in this embodiment has two installation methods: For conductors of medium diameter, such as those in overhead transmission lines, when the diameter of the conductor matches the diameter of the through-hole on the bottom surface of the metal casing, a "set-up" installation method can be used: first, a through-hole matching the diameter of the conductor is machined in the center of the bottom surface of the metal casing; then, the metal casing is moved to the predetermined position along the axial direction of the conductor. The rotating hinge design allows for easier orientation and fixation of the conductor, avoiding the instability that may arise from traditional fixing methods. Combined with fixing bolts, the rotating hinge ensures that the conductor's position does not shift under high voltage conditions. To prevent the device from sliding along the axial direction of the conductor, a soft conductive or semi-conductive material such as silicone can be filled between the through-hole and the conductor to enhance mechanical interlocking force and maintain electrical contact. Figure 2 As shown.

[0121] When the radius of the conductor being tested is small, the device is designed as a coaxial, side-opening structure. A through-hole matching the diameter of the conductor is machined directly into the center of the bottom surface of the metal casing, and the casing is then fitted onto the outside of the conductor. To prevent the device from sliding along the axial direction of the conductor, a soft conductive or semi-conductive material such as silicone can be filled between the through-hole and the conductor to enhance mechanical engagement and maintain electrical contact. When the diameter of the conductor being tested is large and cannot be installed by directly fitting the casing into the center, the device can use a tubular clamp (or electrical clamp) made of conductive material to fix the metal casing to the outer surface of the conductor, ensuring that the metal casing still maintains a good electrical connection with the conductor, thereby achieving overall equipotential. Figure 4 As shown.

[0122] The sensor array is mounted inside a metal housing and reliably connected to it via a metal bracket. The metal bracket can be fixed to the housing by welding or screws to ensure that the sensor array, metal bracket, and metal housing form a unified equipotential body. The metal bracket may have pre-drilled threaded holes, elongated holes, or other structures for fine-tuning and locking, allowing for precise adjustment of the sensor array's position and orientation and ensuring stable fixation. A metal partition is located inside the metal housing, confining the sensor array within a predetermined enclosed space and providing electromagnetic and mechanical isolation from other components (such as energy harvesting modules and communication modules) that may be located inside the housing, reducing interference from other devices in the electric field measurement.

[0123] After installation, the electric field around the conductor under test is modulated by the aperture array, so that different electric field sensors set inside the metal shell can sense different electric field strengths.

[0124] In this embodiment, in the installed state, the geometric center of the sensor array and the axis of the conductor being measured are located in the same plane, and the normal of the sensing surface of each sensor points outward along the outer normal direction of the sidewall of the metal casing. An aperture array is disposed on the sidewall of the metal casing, with each aperture coaxially arranged with the sensing surface of its corresponding sensor; the overall axis of the aperture array remains perpendicular to the ground plane to ensure consistency of the measurement direction. The aperture size and the distance from the sensor sensing surface to the inner wall of the casing are determined through electric field simulation calculations to achieve the optimal trade-off between sensitivity, linearity, and shielding effect.

[0125] The number and geometry of the sensor arrays in this invention can be flexibly adjusted based on different application scenarios and measurement requirements. In space-constrained environments, an array layout consisting of two triangular sensors can be used; for applications requiring high voltage measurement accuracy, multiple circular sensor arrays can be deployed, uniformly distributed along the axis of the metal support to ensure stable electric field acquisition; furthermore, in applications with stringent requirements for high-resolution voltage measurement, using n square sensor arrays and configuring them appropriately can further improve measurement accuracy and signal differentiation.

[0126] In addition, temperature and humidity sensors, wind speed sensors, and other devices can be added inside the device to detect environmental changes and obtain real-time environmental parameters. When the external environment changes, the measuring device can compensate and correct the voltage measurement results based on the aforementioned environmental parameters, thereby maintaining high measurement accuracy under different operating conditions.

[0127] According to the principles of electromagnetism, the closer the equipotential body formed by the conductor being measured and the measuring device is to the ground plane, the stronger the electric field, and the greater the change in field strength at the same distance; conversely, the field strength decreases and the change is less noticeable at greater distances. Keeping the distance between the sensor's sensing surface and the inner surface of the metal casing constant, the overall change in height of the conductor being measured approximates an exponential form, expressed as:

[0128] Where E is the electric field of the sensor's sensing surface.

[0129] Simulation calculations show that the electric field intensity E on the sensor surface changes more drastically with the distance r from the sensor sensing surface to the inner surface of the housing, exceeding the change with h. Therefore, by adjusting r for different sensors, the readings of different sensors can be made different, forming a differential, which can suppress the influence of electromagnetic interference from a distance and the interference caused by ground potential fluctuations due to changes in h on the measurement results.

[0130] When other parameters remain unchanged, the electric field strength E on the sensor surface is positively correlated with the aperture radius a. The larger the radius, the weaker the shielding effect. The sensor field strength can be adjusted by adjusting the aperture radius so that the electric field value of the sensing surface of the electric field sensor meets the range of the electric field sensor, and the difference between the readings of each sensor is as large as possible so that the voltage inversion calculation can be performed using the difference in electric field.

[0131] Therefore, this invention provides two design approaches: 1. The sensor's sensing surface is at the same distance from the inner side of the metal casing, but the corresponding apertures are different.

[0132] First, a simulation model is constructed based on given parameters, including the diameter of the conductor being measured, its height above ground, voltage level, the radius of the metal casing, and the distance between the sensor's sensing surface and the inner side of the metal casing. The electric field on the corresponding sensor's sensing surface is obtained by changing the aperture size. Then, an appropriate aperture size is selected based on the sensor's measurement range, while maximizing the difference in readings between each sensor within the allowable range. Finally, an inverse calculation is performed based on the relationship between the conductor voltage and the difference in electric field sensor readings.

[0133] 2. The sensors have the same aperture, but the distance between the sensing surface and the inner side of the metal casing is different.

[0134] First, based on given parameters including the diameter of the conductor being measured, its height above ground, voltage level, and the radius of the metal casing, a simulation model is constructed. Then, by changing the aperture radius, the electric field distribution along the casing radius is obtained for different aperture radii. Next, the sensor range is selected, and the aperture size is determined. Finally, based on the electric field distribution, the distance from the sensor's sensing surface to the side of the metal casing is selected, while maximizing the difference in readings between each sensor within the allowable range. Finally, an inverse calculation is performed based on the relationship between the conductor voltage and the difference in electric field sensor readings.

[0135] When the number of sensors n is deployed inside the device, they will form a differential structure in pairs, and a total of [number] can be obtained. Differential data is used to effectively avoid large errors caused by anomalies in a single differential data point. Through differential electric field data and combined with actual field calibration results, the fitting equation between the calibration conductor voltage V and the differential sensor output is derived via data fitting:

[0136] At this point, the electric field-voltage relationship is nonlinear. To further improve the accuracy of voltage inversion, we fix the constant c and use the Gauss-Newton iteration method, which solves the nonlinear problem linearly, to progressively update the inversion parameters a and b. Using this as a bridge, we can derive the inverted voltage. The coefficients a and b of the first and second terms of the fitted equation and the difference electric field value There is a functional relationship between them:

[0137] Let the vector of n independent variables consisting of three parameters be... Linearization is performed using Taylor expansion, and here we define... For the residual vector, Given a Jacobian matrix, we can obtain the following formula:

[0138] By minimizing the residual vector, the optimal voltage solution is gradually approximated, and finally a stable and high-precision voltage inversion result is obtained.

[0139] This embodiment provides various sensor support schemes and high-precision data processing methods based on different numbers of sensors in practical applications, such as... Figure 6-7 As shown, the three sensors are evenly arranged, numbered 1, 2, and 3. Each sensor is embedded in one of three adjacent grooves, with the grooves spaced evenly along the horizontal center line of the support. Figure 8 The diagram shows a dual-sensor arrangement, with two sensors located in triangular openings at different heights, numbered 1 and 2. This arrangement is suitable for elevation difference inversion or near-field-far-field difference analysis. Figure 9 The diagram shows a four-sensor arrangement. The sensors are arranged sequentially along a horizontal straight line and numbered 1, 2, 3, and 4. More mounting positions are reserved on the right end of the structure, which can be further expanded to n sensors. This is suitable for acquiring more differential data to enhance the stability and accuracy of the inversion.

[0140] To further improve the accuracy of the inverted voltage, this embodiment employs a Gauss-Newton iterative algorithm to solve the nonlinear model. Thanks to the multi-difference structure formed by deploying different numbers of sensors at different locations, a system can be constructed using... The residual vector r(ζ) is composed of the group difference data and their corresponding fitting expressions, where ζ=[a,b,ΔE]. t Let be the vector of independent variables. After initializing the parameters a and b in the inversion formula, a first-order Taylor expansion of the function is performed to construct its Jacobian matrix J(ζ). The inversion result is then substituted into... Figure 12 In the iterative process, the inversion parameters are updated, and this process is repeated until the inversion voltage solution is deemed convergent. Through the above iterative process, the optimal inversion voltage solution V can be gradually approximated. o This method achieves robust fitting under differential electric field data perturbations. The final results exhibit high stability and accuracy, making them suitable for non-invasive voltage measurements of medium-diameter conductors in typical engineering scenarios.

[0141] In practical applications, if the device and the conductor being measured are installed in the following way... Figure 2 Internal sensor deployment methods are as follows Figure 10As shown, the electric field strength at each measurement point is changed by altering the distance between the sensor and the inner surface of the device's metal casing.

[0142] The diameter and basic structure of the conductor being measured are moderate. The diameter of the through-hole in the device matches the diameter of the conductor being measured. It is installed using a "set-up" method. After adjusting the relative position of the device and the conductor being measured, tighten the fixing bolts to ensure that the device will not have relative displacement with respect to the conductor. The distances from the sensing surfaces of the three electric field sensors to the inner surface of the housing are changed, respectively by x, ... , .

[0143] Let the readings of n electric field sensors from left to right be Ex, Ey, and Ez. These are paired to form a differential structure, yielding three sets of differential electric field measurements at different heights. Initialize the inversion parameters a and b, substitute the differential electric field data into the inversion formula, and simultaneously enter the iterative process, comparing the residual vector magnitudes before and after the update. The size of the parameter is determined, and smaller parameter information is retained for the next iteration. The parameter value is output after the convergence condition is met or the maximum number of iterations is reached.

[0144] In practical applications, if the device and the conductor being measured are installed in the following way... Figure 2 Internal sensor deployment methods are as follows Figure 6-9 As shown, the electric field strength at each measurement point can be changed by altering the size, number, and shape of the corresponding aperture of the sensor.

[0145] The diameter of the conductor being measured and its basic structure are moderate. The diameter of the through-hole of the device matches the diameter of the conductor being measured. They are installed using a "set-on" method. After adjusting the relative position of the device and the conductor being measured, tighten the fixing bolts to ensure that the device will not have relative displacement with respect to the conductor. Change the aperture diameters of the three electric field sensors to x, ... x ,like Figure 11 As shown.

[0146] Let the readings of n electric field sensors from left to right be Ex, Ex+a, and Ex+b. These are paired to form a differential structure, yielding three sets of differential electric field measurements along the aperture diameter. Initialize the inversion parameters a and b, substitute the differential electric field data into the inversion formula, and simultaneously enter the iterative process, comparing the residual vector magnitudes before and after the update. The size of the parameter is determined, and smaller parameter information is retained for the next iteration. The parameter value is output after the convergence condition is met or the maximum number of iterations is reached.

[0147] Furthermore, after modulation, the output signals of at least two electric field sensors are acquired, and differential electric field data is constructed based on the output signals. Based on the nonlinear relationship between the pre-established differential electric field data and the voltage of the conductor under test, the differential electric field data is inverted to obtain the voltage of the conductor under test.

[0148] Specifically, mounting the metal housing 100 onto the conductor 1000 under test, thus electrically connecting the metal housing 100 and the conductor 1000 to form an equipotential body, is a crucial step in ensuring a stable electrical reference between the measuring device and the conductor 1000. This provides a stable reference potential for the electric field sensor 210 and ensures that the metal housing 100 itself does not generate additional, uncontrollable interference to the electric field distribution of the conductor 1000. This mounting process can be implemented in various ways. For example, the metal housing 100 can be tightly clamped to the outer surface of the conductor 1000 using a metal clamp 600, while ensuring good electrical contact between the metal clamp 600 and the metal housing 100; or, if the metal housing 100 is designed with a through hole 120, the metal housing 100 can be directly fitted onto the outside of the conductor 1000 under test and electrically connected using fasteners or conductive adhesive; or the metal housing 100 can be fixed to the grounding terminal or reference potential point of the conductor 1000 under test using conductive bolts or conductive washers.

[0149] One of the core techniques of this method is to modulate the electric field around the conductor 1000 under test using the aperture array 110, enabling different electric field sensors 210 located inside the metal casing 100 to sense different electric field intensities. The geometry of the aperture array 110 is cleverly utilized to locally shape or attenuate the electric field generated by the conductor 1000 under test, allowing electric field sensors 210 located at different positions inside the metal casing 100 to receive significantly different electric field signals. This difference is crucial information for subsequent voltage inversion. The methods for achieving electric field modulation can include: different holes in the aperture array 110 can be designed with different aperture diameters, for example, the apertures closer to the conductor 1000 being measured have larger apertures and the apertures farther away have smaller apertures, thereby producing different degrees of attenuation of the electric field; or, the holes in the aperture array 110 can have the same aperture diameter, but the distance between the sensing surface of the corresponding electric field sensor 210 and the inner surface of the metal housing 100 can be different from each other, and the sensed electric field intensity can be modulated by changing the relative position of the sensor and the hole; the electric field can also be further finely modulated by changing the shape of the hole or the thickness of the hole wall.

[0150] Acquiring the output signals of at least two electric field sensors 210 and constructing differential electric field data based on these output signals is a step in obtaining raw measurement data and performing preliminary processing. Acquiring signals from multiple sensors is to obtain spatially differentiated electric field information. Constructing differential electric field data is to eliminate common-mode interference, improve the signal-to-noise ratio, and highlight effective information related to the voltage of the measured conductor 1000. The voltage inversion module 400 can have a built-in analog-to-digital converter (ADC) to convert the analog voltage signals output by each electric field sensor 210 into digital signals. Then, a software algorithm can be used to subtract the digital signals from any two or more sensors to obtain the differential value. Alternatively, in the analog front-end circuit, a differential amplifier can be directly used to differentially process the analog output signals of the two electric field sensors 210, and then the differential signal can be sent to the ADC for digitization. Furthermore, the output signals of all electric field sensors 210 can be differentially processed pairwise to construct multiple sets of differential electric field data to provide richer information.

[0151] Based on the pre-established nonlinear relationship between the differential electric field data and the voltage of the measured conductor 1000, the differential electric field data is inverted to obtain the voltage of the measured conductor 1000. This is a crucial step in converting the processed electric field data into the final voltage measurement result. Since there is usually a complex nonlinear relationship between the electric field distribution and the conductor voltage, pre-establishing this relationship model is fundamental to achieving accurate inversion. The inversion calculation uses this model to map the differential electric field data to the voltage value of the measured conductor 1000. Methods for pre-establishing the nonlinear relationship include: simulating the electric field distribution of the device using finite element analysis (FEA) software, simulating the output of the electric field sensor 210 and the differential electric field data under different voltages of the measured conductor 1000, thereby establishing a nonlinear lookup table or polynomial fitting model; or, through experimental calibration, testing the device under a known voltage source, recording the differential electric field data corresponding to different voltage values, and then using regression analysis, neural networks, or other machine learning algorithms to establish a nonlinear mapping model. The inversion calculation can employ iterative algorithms, least squares methods, support vector machines (SVM), or deep learning models, inputting the real-time collected differential electric field data into a pre-established model and outputting the voltage value of the measured conductor 1000.

[0152] This method first installs a metal casing 100 on the conductor 1000 under test, electrically connecting them to form an equipotential body. This provides a stable electrical reference for the entire measurement system, effectively isolating external environmental electric field interference and ensuring the determinism of the measurement environment. Subsequently, a carefully designed array of holes 110 on the metal casing 100 locally modulates the electric field generated by the conductor 1000, enabling different electric field sensors 210 located inside the metal casing 100 to sense spatially differentiated electric field strengths. This differentiated electric field signal forms the basis for subsequent accurate voltage inversion. The voltage inversion module 400 acquires the output signals of these differentiated electric field sensors 210 and further constructs differential electric field data. Differential processing effectively suppresses common-mode noise and environmental fluctuations, significantly improving the signal-to-noise ratio, thereby more accurately extracting effective information directly related to the voltage of the conductor 1000 under test. Finally, based on the pre-established nonlinear relationship between the differential electric field data and the voltage of the conductor 1000 under test, the voltage inversion module 400 performs inversion calculations on the differential electric field data to accurately obtain the voltage of the conductor 1000 under test. Through this series of steps, this method transforms the spatially modulated and differentially processed electric field signal into a reliable voltage measurement result, effectively overcoming the problems of signal susceptibility to interference and low inversion accuracy in traditional non-invasive electric field measurements.

[0153] As a specific implementation, the aforementioned non-invasive voltage measuring device can be applied to measure the voltage of a high-voltage cable (the conductor under test 1000). First, a metal casing 100 is tightly clamped to the outer surface of the high-voltage cable using a metal clamp 600. The metal clamp 600 ensures a reliable electrical connection between the metal casing 100 and the high-voltage cable, thus forming an equipotential body. An array of holes 110 is provided on the sidewall of the metal casing 100, containing two holes, one with a larger diameter and the other with a smaller diameter. Two electric field sensors 210 are respectively positioned corresponding to these two holes, with their sensing surfaces facing the corresponding holes. When the high-voltage cable is energized, an electric field is generated around it. Due to the difference in the hole diameters in the array 110, the electric field attenuation is smaller through the larger hole and larger through the smaller hole, resulting in a significant difference in the electric field strength sensed by the two electric field sensors 210. The voltage inversion module 400 acquires the output signals of the two electric field sensors 210 in real time; for example, sensor A outputs signal VA, and sensor B outputs signal VB. The voltage inversion module 400 performs differential processing on VA and VB to construct differential electric field data ΔV = VA - VB. Before the device was put into use, a lookup table was established through experimental calibration. This lookup table records the nonlinear correspondence between the differential electric field data ΔV and the high-voltage cable voltage under different known voltages. When the real-time differential electric field data ΔV is obtained, the voltage inversion module 400 queries this lookup table or performs calculations using a preset nonlinear function model to invert the current voltage value of the high-voltage cable.

[0154] Through the above technical solution, this application provides a design method for a non-invasive voltage measurement device, which can effectively solve the problems of electric field signals being easily interfered with and the difficulty in accurately inverting voltage in traditional non-invasive measurements. By forming an equipotential body between the metal shell 100 and the conductor 1000 under test, a stable reference standard is provided for the measurement. The unique modulation effect of the aperture array 110 on the electric field allows different electric field sensors 210 to sense differentiated electric field strengths, providing rich and effective information for subsequent differential processing. Constructing differential electric field data can effectively suppress common-mode interference and environmental noise, significantly improving the signal-to-noise ratio and stability of the measurement signal. Based on the pre-established nonlinear relationship, the inversion calculation can accurately convert the processed electric field data into the voltage of the conductor 1000 under test, thereby realizing high-precision and high-reliability non-invasive voltage measurement.

[0155] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A non-invasive voltage measuring device, characterized in that, include: A metal casing, and a sensor array and voltage inversion module with at least two electric field sensors disposed inside the metal casing; The metal casing has at least one array of holes on its sidewall, each array of holes including at least two holes; the metal casing is electrically connected to the conductor being measured in the installed state and forms an equipotential body. Each of the electric field sensors is configured to correspond to one of the holes in the hole array, and the sensing surface of the electric field sensor faces the corresponding hole; The voltage inversion module is electrically connected to each of the electric field sensors; The voltage inversion module acquires the output signals of each electric field sensor, performs differential calculation on the output signals of at least two electric field sensors to obtain differential electric field data, and inverts the voltage of the conductor under test based on the differential electric field data. The holes in the hole array have different apertures, and the distance between the sensing surface of the corresponding electric field sensor and the inner surface of the metal shell is the same. or, The holes in the hole array have the same aperture, and the distances between the sensing surface of the corresponding electric field sensor and the inner surface of the metal casing are different from each other.

2. The non-invasive voltage measuring device according to claim 1, characterized in that, The non-invasive voltage measuring device also includes a metal bracket, which is located at the position of the hole array and is electrically connected to the inner wall of the metal housing by welding or screw connection, so that the sensor array, the metal bracket and the metal housing form an equipotential body.

3. The non-invasive voltage measuring device according to claim 2, characterized in that, An adjustment structure is provided on the metal support for fine-tuning the position and orientation of each electric field sensor in the sensor array.

4. The non-invasive voltage measuring device according to claim 2, characterized in that, Also includes: A metal partition, located inside the metal housing and connected to the metal support, forms a closed space for enclosing the sensor array.

5. The non-invasive voltage measuring device according to claim 1, characterized in that, The metal casing is cylindrical in shape, with a through hole at the bottom. The diameter of the through hole matches the outer diameter of the conductor being tested, so that the metal casing can be fitted onto the outside of the conductor being tested after installation and form an equipotential body with the conductor being tested.

6. The non-invasive voltage measuring device according to claim 1, characterized in that, Also includes: A metal clamp that simultaneously clamps the outer surface of the metal housing and the conductor under test, and the metal clamp is electrically connected to the metal housing so that the metal housing and the conductor under test form an equipotential body.

7. The non-invasive voltage measuring device according to any one of claims 1-6, characterized in that, The voltage inversion module is specifically used for: The output signals of all electric field sensors are processed pairwise to construct multiple sets of differential electric field data; Based on multiple sets of differential electric field data, the voltage of the conductor under test is obtained by inverting the nonlinear relationship between the differential electric field data and the voltage of the conductor under test.

8. The non-invasive voltage measuring device according to claim 7, characterized in that, The voltage inversion module is also used for: An iterative optimization algorithm is used to update the voltage inversion parameters in the nonlinear relationship to improve the inversion accuracy.

9. A design method for a non-invasive voltage measuring device applied to any one of claims 1-8, characterized in that, include: The first parameter of the conductor under test, the second parameter of the metal casing in the non-invasive voltage measuring device, and the performance parameters of the electric field sensor are obtained, wherein the metal casing is an equipotential body surrounding the conductor under test, and the side wall of the metal casing is provided with an opening through which the electric field passes. Based on the first parameter, the second parameter, and the performance parameter, an electric field simulation model is established that includes the conductor under test, the metal shell, and the opening. By adjusting the size of the opening and / or adjusting the distance between the sensing surface of the electric field sensor and the inner surface of the metal housing, the electric field intensity distribution on the sensing surface is calculated using the electric field simulation model. Based on the range of the electric field sensor and the electric field intensity distribution, determine a configuration scheme for at least two of the electric field sensors; Based on the configuration scheme, determine the actual size of the opening and / or the actual installation position of the electric field sensor; Based on the actual installation location and the actual size of the opening, adjust each electric field sensor in the non-invasive voltage measuring device to obtain the target voltage measuring device, and install it on the conductor to be measured.

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