Hundred-ka high impulse current sensing apparatus based on multi-composite magnetic core materials

Abstract

Provided is a hundred-kA high impulse current sensing apparatus based on multi-composite magnetic core materials. The apparatus comprises: a multi-composite magnetic core framework, a multi-turn current winding coil, at least one parallel resistor, and a shielding housing. The multi-composite magnetic core framework is fabricated from a composite of at least two magnetic materials. The multi-turn current winding coil is distributed on the multi-composite magnetic core framework. The parallel resistor is connected to two ends of the multi-turn current winding coil. The shielding housing is located outside the multi-composite magnetic core framework. A current conductor to be measured penetrates through the multi-composite magnetic core framework in the axial direction of the multi-composite magnetic core framework. A measurement output terminal of the multi-turn current winding coil is connected to an output circuit.

Description

100kA impulse high current sensing device based on multi-composite magnetic core material

[0001] This application claims priority to Chinese patent application No. 202510205011.1, filed on February 24, 2025, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This disclosure belongs to the technical field of electrical measurement, and particularly relates to a 100kA impulse high current sensing device based on multi-composite magnetic core material. Background Technology

[0003] High-amplitude impulse current measurement technology is a fundamental supporting technology for evaluating the current withstand capability of devices such as lightning protection equipment and surge protectors. It is also a fundamental supporting technology for scenarios such as impulse grounding resistance measurement, distributed traveling wave fault location, and lightning strike fault analysis. Therefore, the accuracy of impulse high current measurement directly affects the validity of evaluation data and results.

[0004] Large impulse currents are characterized by high amplitude, short duration, and wide frequency coverage. Furthermore, during measurement, large impulse currents trigger coupled impulses involving transient electromagnetic, thermal, and mechanical multi-physics fields. With the continuous development of power transmission technology, the amplitude of impulse currents is constantly increasing, reaching as high as 200kA.

[0005] In related technologies, the current amplitude of impulse shunts is difficult to exceed hundreds of kiloamperes (kA). As the amplitude of large impulse currents further increases, existing measuring devices struggle to meet the calibration requirements of various industries in terms of measurement amplitude range, waveform parameter types, and performance verification methods. Furthermore, the theoretical framework of traceability methods in related technologies is incomplete, making it difficult to further reduce measurement uncertainty. Rogowski coils are susceptible to external factors such as eccentricity, hindering accuracy improvement, and electromagnetic current sensors are prone to saturation under high current, limiting their high-frequency characteristics. Summary of the Invention

[0006] In a first aspect, a 100kA impulse high-current sensing device based on a multi-composite magnetic core material is provided. This 100kA impulse high-current sensing device includes: a multi-composite magnetic core frame, a multi-turn current-wound coil, at least one parallel resistor, and a shielding shell. The multi-composite magnetic core frame is composed of at least two magnetic materials, and the multi-turn current-wound coil is distributed on the multi-composite magnetic core frame. The parallel resistor connects the two ends of the multi-turn current-wound coil. The shielding shell is located on the outside of the multi-composite magnetic core frame. The conductor carrying the current to be measured passes through the multi-composite magnetic core frame axially, and the measurement output terminal of the multi-turn current-wound coil is connected to an output circuit.

[0007] Secondly, a design method for a 100kA impulse high-current sensing device based on multi-composite magnetic core materials is provided. This method is used to obtain the aforementioned 100kA impulse high-current sensing device based on multi-composite magnetic core materials. The method includes: calculating the ampere-seconds of the current waveform to be measured based on its parameters; calculating the bandwidth requirement based on the frequency content of the current waveform to be measured; determining the proportion and superposition method of each material in the multi-composite magnetic core material based on the bandwidth requirement; determining the dimensions of the multi-composite magnetic core frame based on the ampere-seconds of the current waveform to be measured and the parameters of the multi-composite magnetic core material; conducting a magnetic saturation characteristic test on the multi-composite magnetic core frame to obtain its BH curve; determining the winding diameter, number of turns, and number of segments of the current winding coil using the sensitivity, upper cutoff frequency, lower cutoff frequency, winding resistance, and heat generation of the current sensing device as constraints; calculating the grouped induced voltage, inter-turn capacitance, equivalent inductance, and capacitance to ground of the current winding coil for rationality verification; and determining the reliable operating range of the pulse current coil based on the parameters of the current sensing device if the rationality verification is successful.

[0008] Thirdly, a computer-readable storage medium is provided. This computer-readable storage medium stores a computer program. The computer program is configured to execute the aforementioned design method for a 100kA impulse high-current sensing device based on multi-composite magnetic core materials.

[0009] Fourthly, an electronic device is provided. This electronic device includes a memory and a processor. The memory stores a computer program, and the processor is configured to execute the design method of the aforementioned 100kA impulse high-current sensing device based on multi-composite magnetic core materials through the computer program. Attached Figure Description

[0010] Figure 1 is a schematic diagram of a typical inrush current waveform;

[0011] Figure 2 is a structural diagram of a 100kA impulse high current sensing device based on multi-composite magnetic core material according to some embodiments;

[0012] Figure 3 is a cross-sectional view of a multi-composite magnetic core frame according to some embodiments;

[0013] Figure 4 is a schematic diagram of the winding method of the current-wound coil on the multi-composite magnetic core frame according to some embodiments;

[0014] Figure 5 is a schematic diagram of the measurement principle of the magnetic core current coil according to some embodiments;

[0015] Figure 6 is a flowchart of a design method for a 100kA impulse high current sensing device based on multi-composite magnetic core material according to some embodiments.

[0016] Figure 7 is another flowchart of a design method for a 100kA impulse high current sensing device based on multi-composite magnetic core material according to some embodiments.

[0017] Figure 8 is a block diagram of an electronic device according to some embodiments. Detailed Implementation

[0018] The present disclosure will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present disclosure will become clearer from the following description and claims. It should be noted that the drawings are all in a very simplified form and are not to scale, and are only used to facilitate and clarify the illustration of the embodiments of the present disclosure.

[0019] It should be noted that, in order to clearly illustrate the content of this disclosure, several embodiments are provided to further explain the different implementations of this disclosure. These embodiments are enumerated rather than exhaustive. In addition, for the sake of brevity, content mentioned in the previous embodiments is often omitted in the later embodiments. Therefore, content not mentioned in the later embodiments can be referred to the previous embodiments accordingly.

[0020] Unless the context otherwise requires, throughout the specification and claims, the term "comprise" and its other forms, such as the third-person singular "comprises" and the present participle "comprising," are interpreted as open-ended and encompassing, meaning "including, but not limited to." In the description of the specification, terms such as "one embodiment," "some embodiments," "exemplary embodiments," "example," "specific example," or "some examples," etc., are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this disclosure. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics mentioned may be included in any suitable manner in any one or more embodiments or examples.

[0021] In describing some embodiments, the term "connection" and its derivative expressions may be used. The term "connection" should be interpreted broadly; for example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a direct connection or an indirect connection through an intermediate medium. The embodiments disclosed herein are not necessarily limited to the content of this document.

[0022] Typically, the waveform of an impulse current is shown in Figure 1. The characteristic parameters of the impulse current waveform include three parameters: peak current, wavefront time T1, and wavetail time T2. The time parameters (i.e., T1 / T2) of the impulse current waveform to be measured are (1 / 20) μs, (4 / 10) μs, (8 / 20) μs, and (10 / 350) μs, with a rise time of several microseconds (μs) and a fall time of tens to hundreds of microseconds. The waveform frequency ranges from 0 Hz to several megahertz (MHz), which places extremely high demands on the response characteristics and bandwidth of the measuring device.

[0023] Impulse current measuring devices are key measuring equipment for conducting impulse current withstand tests on electrical equipment. The accuracy of impulse current measuring devices directly affects the safety and economy of power equipment. An effective method to ensure the accuracy and consistency of measurement values ​​is traceability. Traceability methods use a continuous chain of comparisons with specified uncertainties to trace measurement results back to national or international standards.

[0024] Standard impulse current measuring devices are crucial equipment in the traceability of impulse current values. Using these devices as reference standards, the corresponding standard values ​​are transmitted to impulse current measuring devices at various levels. Therefore, continuously improving the measurement amplitude of standard impulse currents and enhancing the accuracy of impulse current waveform parameters is one of the directions for high-voltage, high-current metering work.

[0025] The impulse shunt is the earliest and most direct measurement method. Its measurement principle is based on Ohm's law. Essentially, an impulse shunt is a measuring resistor; the current to be measured flows through it, generating a voltage across its terminals. This voltage value is used to determine the resistance value, thus obtaining the waveform parameters of the measured current. Impulse shunts typically employ a coaxial structure and offer advantages such as stable resistance, compact design, low stray inductance, and excellent high-frequency response characteristics. Therefore, impulse shunts are commonly used for measuring impulse currents in the hundreds of kA range.

[0026] However, due to limitations in its measurement principle, the impulse shunt needs to be connected in series with the current loop under test. This type of measuring device cannot be used when the current loop is compact or the installation location is limited. Furthermore, when the amplitude of the current under test exceeds 100kA, the impulse shunt overheats significantly and cannot dissipate heat effectively, causing changes in its resistance and affecting measurement accuracy. When measuring steep-pulse impulse currents, the impulse shunt may exhibit a skin effect under high-frequency signal action, resulting in low resistor utilization and resistance changes. When measuring wide-pulse impulse current waveforms, the cumulative thermal effect further reduces the measured amplitude, failing to meet the ever-increasing demand for impulse current measurement.

[0027] A Rogowski coil with a magnetic core is used as the standard measuring device for inrush current, and the magnetic core coil adopts a single-coil winding structure. When the amplitude and pulse width of the current to be measured increase, the measuring device is prone to magnetic saturation. When using a single-coil winding structure, the measuring device cannot simultaneously meet the requirements of output sensitivity, upper limit frequency, and response time, making it difficult to measure inrush currents above 100kA. Furthermore, due to the limitations of the magnetic core's frequency band characteristics, this measuring device is difficult to respond to current waveforms with ultra-high frequency components.

[0028] When using an air-core Rogowski coil to measure high-current impulse waveforms, theoretically, it can measure impulse current waveforms ranging from hundreds of kA to several megaamperes (mA) because the air-core Rogowski coil has no magnetic core. However, the air-core coil requires an external passive or active integrating circuit to achieve high-current impulse measurement. When the external integrating circuit is passive, the low-frequency characteristics of the air-core Rogowski coil are limited; when an active integrating circuit is used, the current coil is easily affected by spatial electric and magnetic fields due to the introduction of the power supply circuit, making it difficult to improve measurement accuracy. Therefore, the air-core Rogowski coil cannot be used as a standard measuring device for impulse current.

[0029] The most important parameters for high-current impulse waveforms are peak value, wavefront time, and wave tail time. Currently, various high-current impulse measurement sensors cannot accurately measure high-current impulse waveforms exceeding 100kA. They suffer from poor response characteristics, inability to accurately reproduce high-current impulse waveforms, inability to obtain peak value and time characteristic parameters of the impulse current waveform, and inability to accurately obtain standard values ​​of high-current impulses.

[0030] To address the aforementioned problems, this disclosure provides an embodiment of a 100kA impulse high current sensing device 100 based on a multi-composite magnetic core material. As shown in FIG2, the device 100 includes: a multi-composite magnetic core frame 10, a multi-turn current winding coil 20, a parallel resistor 30, and a shielding shell 40. The multi-composite magnetic core frame 10 is composed of at least two magnetic materials. The multi-turn current winding coil 20 is distributed on the multi-composite magnetic core frame 10, and the parallel resistor 30 connects the two ends of the multi-turn current winding coil 20. The shielding shell 40 is located on the outside of the multi-composite magnetic core frame 10. The current-to-be-measured conductor 50 passes through the multi-composite magnetic core frame 10 axially, and the measurement output terminal of the multi-turn current winding coil 20 is connected to an output circuit.

[0031] In some embodiments, as shown in FIG2, the multi-turn current-wound coil 20 is formed in a multi-segment form and distributed on the multi-composite magnetic core frame 10, with the multiple sets of current-wound coils 20 connected in series. For example, the multi-turn current-wound coil 20 includes multiple sets of current-wound coils 20 connected in series.

[0032] In some embodiments, as shown in FIG2, a parallel resistor 30 is connected to both ends of each group of current-wound coils 20.

[0033] By using multi-composite magnetic core materials as the winding skeleton of the current coil and adopting a multi-segment winding structure, the response characteristics of the measuring device can be optimized and the measurement current amplitude and bandwidth can be expanded while ensuring the sensitivity of the sensing device.

[0034] In some embodiments, the multi-composite magnetic core frame 10 is composed of magnetic laminations made of at least two materials, with each layer of magnetic laminations having a thickness of less than or equal to 10 μm. For example, as shown in FIG3, the multi-composite magnetic core frame 10 includes magnetic laminations made of magnetic core material 1, magnetic laminations made of magnetic core material 2, and magnetic laminations made of magnetic core material 3, which are stacked sequentially. Furthermore, the thickness of each layer of magnetic laminations is equal to 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, or 10 μm.

[0035] In some embodiments, the magnetic laminations of each material are symmetrically distributed along the axial direction of the multi-composite magnetic core frame 10. For example, as shown in FIG3, the multi-composite magnetic core frame 10 includes two magnetic laminations using magnetic core material 1, two magnetic laminations using magnetic core material 2, and two magnetic laminations using magnetic core material 3. The two magnetic laminations of magnetic core material 1 are symmetrically distributed along the axial direction of the multi-composite magnetic core frame 10, the two magnetic laminations of magnetic core material 2 are symmetrically distributed along the axial direction of the multi-composite magnetic core frame 10, and the two magnetic laminations of magnetic core material 3 are symmetrically distributed along the axial direction of the multi-composite magnetic core frame 10.

[0036] In some embodiments, as shown in FIG2, the shielding shell 40 includes a low-frequency magnetic shielding shell 41, a high-frequency magnetic shielding shell 42, and an electrical shielding shell 43. The low-frequency magnetic shielding shell 41 is used to shield low-frequency magnetic field interference signals within 1MHz, and the high-frequency magnetic shielding shell 42 is used to shield high-frequency magnetic field interference signals above 1MHz. For example, the low-frequency magnetic shielding shell 41 is used to shield magnetic field interference signals at frequencies of 0.1MHz, 0.2MHz, 0.3MHz, 0.4MHz, 0.5MHz, 0.6MHz, 0.7MHz, 0.8MHz, 0.9MHz, or 1MHz; the high-frequency magnetic shielding shell 42 is used to shield magnetic field interference signals at frequencies of 1MHz, 5MHz, 10MHz, 20MHz, 30MHz, 60MHz, 100MHz, 300MHz, 500MHz, or 1000MHz.

[0037] In some embodiments, as shown in FIG2, the high-frequency magnetic shielding shell 42 is located between the low-frequency magnetic shielding shell 41 and the electrical shielding shell 43, with the electrical shielding shell 43 located on the outermost layer.

[0038] In some embodiments, the multi-composite magnetic core frame 10 is wrapped with an insulating layer, and the current-wound coil 20 is wrapped with an insulating layer.

[0039] In some embodiments, the magnetic material of the multi-composite magnetic core frame 10 includes: ferrite, microcrystalline alloy, and permalloy.

[0040] The core material of the multi-composite magnetic core frame 10 is not limited to a composite of multiple core materials such as ferrite, microcrystalline alloy, and permalloy. Compared with a single core material, the multi-composite magnetic core material has a wider bandwidth and a larger magnetic saturation range. To ensure the uniformity of the magnetic field strength in the core material, multiple different core materials are stacked uniformly and symmetrically, and each layer of magnetic stack material is toroidal with a thickness of less than or equal to 10 μm. Of course, the cross-section of the multi-composite magnetic core frame 10 is not limited to that shown in Figure 3. According to the actual current waveform to be measured, multiple thin core materials are stacked and pressed into a toroidal composite magnetic core material of the required size. The bandwidth of this toroidal composite magnetic core material can cover 0.1 Hz to 10 MHz (e.g., 0.1 Hz, 1 Hz, 10 Hz, 100 Hz, 1 kHz, 1 MHz, or 10 MHz), ensuring accurate measurement of exponential and rectangular impulse current waveforms across the entire frequency band.

[0041] A multi-segment combined winding coil series connection method is used for impulse high current measurement, not limited to the method shown in Figure 4. Taking a current winding coil 20 with 6 turns per group as an example, the winding method of two consecutive groups of current winding coils 20 is described below. An impulse current sensor with multi-segment windings can be equivalent to multiple parallel single-winding current coils. The bandwidth of the impulse current sensor with multi-segment windings is determined by the bandwidth of a single winding. Under the action of impulse high current, multiple balanced windings respond synchronously. Due to the reduced number of turns in a single winding, the response speed of a single-winding current coil is effectively improved. Furthermore, with the same core material, size, and shielding layer spacing, the capacitance of a current sensor with multi-segment windings can be m times smaller than that of a single-winding coil current sensor. This reduction in capacitance helps to increase the upper cutoff frequency f. H and response speed.

[0042] To ensure good magnetic shielding performance of the current sensor, a frequency-division magnetic shielding shell is installed on the outer shell of the magnetic core winding coil, with the low-frequency magnetic shielding layer inside and the high-frequency magnetic shielding layer outside. The high-frequency magnetic shielding shell 42 is mainly used to shield high-frequency magnetic field interference signals above 1MHz, while the low-frequency magnetic shielding shell 41 is mainly used to shield low-frequency magnetic field interference signals below 1MHz, thus achieving good shielding effect across the entire frequency band from 0Hz to MHz. Simultaneously, an electrical shielding shell 43 is installed outside the low-frequency magnetic shielding shell 41 and the high-frequency magnetic shielding shell 42 to achieve good electromagnetic shielding effect.

[0043] The measurement principle of a magnetic core current coil is not limited to that shown in Figure 5. The current to be measured passes through a multi-composite magnetic core frame with a current-wound coil wound around it, generating a magnetic field in space. When the current to be measured changes, a voltage U = Mdi / dt, proportional to the rate of change of current, is induced across the coil wound on the multi-composite magnetic core frame. M is the inductance coefficient of the current-wound coil, which is related to the size of the current-wound coil frame and its relative permeability (determined by the core material). Integrating the induced voltage of the current-wound coil yields a voltage value proportional to the value of the current to be measured. By comparing the obtained voltage value with the voltage value of a standard current measuring device, the proportionality coefficient of the current measuring device is obtained.

[0044] In some embodiments of this disclosure, the measurement of high-current impulse based on non-contact magnetic core coils can effectively avoid the heat generated by directly connecting the impulse current measuring device to the high-current circuit, thereby enabling the measurement of hundreds of kA high currents. By optimizing existing magnetic core materials and superimposing magnetic core materials with various different properties, the advantages of multiple magnetic core materials can be superimposed, ensuring that the multi-composite magnetic core materials have wide-band response characteristics, high saturation magnetic field range, and high relative permeability.

[0045] In addition, to address the problem of excessive turns in the 100kA high-current impulse core coil, which leads to poor oscillation and response characteristics due to internal stray inductance and stray capacitance, some embodiments of this disclosure group the multi-turn current-wound coils so that multiple winding segments can respond simultaneously when measuring the impulse current waveform, thereby reducing the response time. Furthermore, by distributing damping to the multiple winding segments, the oscillation amplitude of the response waveform can be reduced, and the measurement error can be reduced, thereby achieving accurate measurement of the impulse high-current waveform and parameters.

[0046] In some embodiments of this disclosure, a 100kA impulse high current sensing device based on multi-composite magnetic core material includes a multi-composite magnetic core frame 10, an insulating layer surrounding the magnetic core frame, multiple sets of current-wound coils 20 on the magnetic core frame, damping resistors connected in parallel across the two ends of the multiple sets of current-wound coils 20, a measurement output terminal of the current-wound coils 20, an insulating layer on the outer layer of the current-wound coils, a low-frequency magnetic shielding shell 41, a high-frequency magnetic shielding shell 42, and an electrical shielding shell 43.

[0047] The winding frame (i.e., the multi-composite magnetic core frame 10) of this current sensor (i.e., the 100kA impulse high current sensing device) adopts a multi-composite magnetic core material. Unlike single magnetic core materials, multi-composite magnetic core materials are composed of laminated composites of various magnetic core materials such as ferrite, microcrystalline alloy, and permalloy. Compared with single magnetic core materials, while ensuring a higher relative permeability, multi-composite magnetic core materials have a wider frequency band and a larger magnetic saturation range.

[0048] To ensure the uniformity of magnetic field strength in the multi-composite magnetic core material, multiple different types of magnetic core materials are stacked evenly and symmetrically and then pressed together. The shape of the magnetic core material can be selected according to the size and shape requirements of the actual current sensor winding frame (it can be a ring or a hollow rectangle). The magnetic core shape can be a rigid iron core with a fixed structure or a double-C structure open and closed iron core.

[0049] The laminated multilayer composite magnetic core materials have the same area. To ensure the uniformity of magnetic field penetration within the core material, the thickness of a single core layer is less than or equal to 10 μm. Based on the requirements of the actual current waveform to be measured, multiple (two or more) thin-film magnetic core materials are laminated into multi-composite magnetic core materials of the desired size and shape. The bandwidth of these multi-composite magnetic core materials can cover 0.1 Hz to 10 MHz, and their relative permeability can be flexibly adjusted between hundreds and hundreds of thousands. This ensures both effective acquisition of low-frequency current signals and accurate measurement of high-frequency signals, thereby guaranteeing accurate full-band measurement of exponential and rectangular impulse current waveforms.

[0050] Based on parameters such as the sensitivity coefficient of the current sensor and the number of turns of the current winding coil, the permeability and structural parameters of the current sensor core material are comprehensively evaluated and calculated in reverse. Then, based on the determined permeability, the type of composite material, the stacking distribution, and the proportion of different core material layers are further determined.

[0051] Unlike traditional electromagnetic impulse current transformers that use a single winding wound from beginning to end, the current sensor proposed in some embodiments of this disclosure uses a multi-segment winding connected in series for measuring large impulse currents. After segmenting the winding, the number of turns in a single segment is reduced. Furthermore, with the same core material, size, and shielding layer spacing, the capacitance of a current sensor with multi-segment windings can be reduced by a factor of m compared to a current sensor with a single winding. This reduction in capacitance helps to improve the upper cutoff frequency f. H and response speed.

[0052] In terms of physical structure, the current sensor consists of multiple windings connected in series. In terms of response characteristics, when a current to be measured is applied to the current sensor, the impulse current sensor with multiple windings can be equivalent to multiple parallel single-winding current coils responding synchronously. The bandwidth of the current sensor is determined by the bandwidth of a single winding. In this way, under the action of a large impulse current, multiple balanced windings can respond synchronously, and the response speed is effectively improved due to the reduced number of turns in the windings.

[0053] The segmentation of multiple windings in a current sensor can be either uniform or non-uniform. When the voltage drop across the winding coils is uneven at the instant the measured current waveform is applied, non-uniform segmentation can improve the uniformity of the voltage distribution across the winding coils, further enhancing the insulation performance of the current sensor. The winding segmentation method of a current sensor is determined by a combination of the rise time of the measured waveform and the proportion of current content in each frequency band.

[0054] To further improve the response characteristics of the current sensor, a resistor is connected in parallel across each segment of the winding. The resistance value of this parallel resistor 30 is determined by the number of coil turns, the sensitivity of the current sensor, and the bandwidth of the current sensor. Furthermore, the power of this parallel resistor 30 is determined by the voltage across the resistor and the loop current. This parallel resistor 30 can function as a damping resistor to suppress oscillations caused by the inductance and parasitic capacitance of the damping coil, and it can also act as an integrating resistor.

[0055] To ensure good electromagnetic shielding performance of the current sensor, a frequency-division magnetic shielding shell is installed outside the insulation layer of the magnetic core winding coil of the current sensor. The low-frequency magnetic shielding layer is inside, and the high-frequency magnetic shielding layer is outside. The high-frequency magnetic shielding shell 42 is mainly used to shield high-frequency magnetic field interference signals above 1MHz, while the low-frequency magnetic shielding shell 41 is mainly used to shield low-frequency magnetic field interference signals below 1MHz, thereby achieving a good shielding effect across the entire frequency band from 0Hz to MHz. Simultaneously, an electrical shielding shell 43 is installed outside both the low-frequency magnetic shielding shell 41 and the high-frequency magnetic shielding shell 42 to achieve a good electromagnetic shielding effect.

[0056] In some embodiments of this disclosure, the current measurement amplitude, pulse width, and waveform bandwidth of the impulse current sensor are significantly improved; by employing a composite superposition of multiple different magnetic core materials, the bandwidth measurement range of the magnetic core material is effectively expanded, and the magnetic saturation range of the magnetic core material is significantly improved; the types and proportions of constituent materials of the multi-composite magnetic core material can be flexibly determined according to the waveform, ampere-seconds (A·s), and bandwidth of the current to be measured, and it is applicable to a wide range of current waveforms; through the multi-segment winding structure, a single multi-turn winding can be reconstructed into multiple windings with fewer turns, and the multi-segment winding... The group can respond synchronously to the same measured current, effectively improving the response speed and the upper limit cutoff frequency of the current sensor; multiple resistors are connected in parallel across the multi-segment windings, which can act as both integrating resistors and distributed damping resistors, effectively suppressing the oscillation amplitude caused by the equivalent inductance and capacitance of the current winding coil under the action of impulse current; the combination of high- and low-frequency segmented magnetic shielding shells and electrical shielding shells 43 achieves a high shielding effect across the entire frequency band, effectively improving the shielding effect of the current sensor and enhancing the measurement accuracy of the current sensor.

[0057] In summary, the 100kA impulse current sensing device based on multi-composite magnetic core materials is not only suitable for measuring impulse current waveforms, but also for designing steep current pulse sensors with short pulse widths and sensors for measuring long pulse widths, demonstrating high versatility.

[0058] This disclosure also provides a design method for a 100kA impulse high-current sensing device based on multi-composite magnetic core materials, used to obtain the aforementioned 100kA impulse high-current sensing device 100 based on multi-composite magnetic core materials. As shown in FIG6, the method includes, but is not limited to, the following steps S602 to S616.

[0059] In step S602, the ampere-seconds of the current waveform under test are calculated based on the parameters of the current waveform under test.

[0060] In step S604, the bandwidth requirement is calculated based on the frequency content of the current waveform to be measured.

[0061] In step S606, the proportion and stacking method of each material in the multi-composite magnetic core material are determined according to the bandwidth requirements.

[0062] In step S608, the dimensions of the multi-composite magnetic core frame are determined based on the ampere-seconds of the current waveform under test and the parameters of the multi-composite magnetic core material. Here, the parameters of the multi-composite magnetic core material may include the proportion and stacking method of each material in the multi-composite magnetic core material.

[0063] In step S610, a magnetic saturation characteristic test is performed on the multi-composite magnetic core skeleton to obtain the magnetization curve (also known as the BH curve) of the multi-composite magnetic core skeleton.

[0064] In step S612, the sensitivity, upper cutoff frequency, lower cutoff frequency, winding resistance, and heat generation of the current sensing device are used as constraints to determine the winding wire diameter, number of turns, and number of segment groups of the current winding coil.

[0065] In step S614, the grouped induced voltage, inter-turn capacitance, equivalent inductance, and capacitance to ground of the current-wound coil are calculated and their rationality is verified.

[0066] In step S616, if the rationality verification is passed, the reliable operating range of the pulse current coil is determined according to the parameters of the current sensing device.

[0067] The design method for a 100kA impulse high-current sensing device based on multi-composite magnetic core materials is not limited to determining the parameters of each part of the 100kA impulse high-current sensing device based on multi-composite magnetic core materials. For example, the method also includes, but is not limited to, the steps shown in Figure 7.

[0068] The amplitude and parameters of the current waveform to be measured are determined, which in turn determines the ampere-seconds (APS) of the current waveform and the upper and lower limits of its frequency. For example, the APS of the current waveform to be measured is calculated based on its parameters. The APS is an important indicator of the measurement capability of a pulse coil, representing the product of the maximum measuring current the coil can withstand and the pulse width.

[0069] Determine the proportions and stacking methods of multiple composite magnetic core materials. For example, determine the proportions and stacking methods of different magnetic core materials in multiple composite magnetic core materials based on bandwidth requirements.

[0070] Determine the inner and outer diameters and height parameters of the multi-composite magnetic core material. For example, based on the ampere-seconds of the current waveform under test and the determined proportions and stacking method of the multi-composite magnetic core materials, determine the inner and outer diameters and height of the multi-composite magnetic core material.

[0071] Determine the BH curve of the wound magnetic core. For example, conduct a magnetic saturation characteristic test on the wound magnetic core to obtain its BH curve.

[0072] Determine the cross-sectional dimensions, number of turns, and number of winding segments. For example, using the sensitivity, upper cutoff frequency, lower cutoff frequency, winding resistance, and heat generation of the current sensor as constraints, preliminarily determine the wire diameter, number of turns, and number of winding segments.

[0073] Determine the shielding thickness parameters between the wound coil and the outer casing. For example, determine the shielding thickness parameters between the wound coil and the outer casing based on insulation requirements and capacitance to ground parameters.

[0074] Determine the transfer function of the current sensor. For example, the transfer function of the current sensor can be determined based on the shielding thickness between the wound coil and the housing, as well as the cross-sectional dimensions, number of turns, and number of winding segments.

[0075] The excitation current value is calculated based on the transfer function of the current sensor, and it is determined whether the excitation current value is saturated. The parameters such as the winding capacitance, resistance, and inductance in the current sensor are also calculated to verify whether the bandwidth meets the design requirements.

[0076] Based on the design results, further calculations were performed on parameters such as the induced voltage of the coil winding, inter-turn capacitance, equivalent inductance, and capacitance to ground to ensure the rationality of the design scheme. The reliable operating range of the pulse current coil was determined based on the final designed parameters.

[0077] This disclosure also provides an electronic device 200 for implementing the design method of the above-described 100kA impulse high-current sensing device based on multi-composite magnetic core materials. This electronic device is not limited to a terminal device or server in a system. As shown in FIG8, the electronic device 200 includes, but is not limited to, a memory 201 and a processor 202. The memory 201 stores a computer program, and the processor 202 is configured to execute the steps in any of the above-described method embodiments via the computer program.

[0078] This disclosure also provides a computer program product or computer program in some embodiments. The computer program product or computer program includes computer instructions stored in a computer-readable storage medium. A computer processor reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer to perform the methods provided in various embodiments of the design method for a 100kA impulse high-current sensing device based on multi-composite magnetic core materials. The computer program is configured to execute the steps in any of the above-described method embodiments when run.

[0079] Some embodiments of this disclosure also provide a computer-readable storage medium (e.g., a non-transitory computer-readable storage medium) storing a computer program that, when run on a computer, causes the computer to execute the design method for a 100kA impulse high-current sensing device based on multi-composite magnetic core materials as described in any of the above embodiments.

[0080] For example, the aforementioned computer-readable storage media may include, but are not limited to: magnetic storage devices (e.g., hard disks, floppy disks, or magnetic tapes), optical discs (e.g., compact disks (CDs), digital versatile disks (DVDs), etc.), smart cards, and flash memory devices (e.g., erasable programmable read-only memory (EPROMs), cards, sticks, or key drives, etc.). The various computer-readable storage media described in this disclosure may represent one or more devices for storing information and / or other machine-readable storage media. The term "machine-readable storage media" may include, but is not limited to, wireless channels and various other media capable of storing, containing, and / or carrying instructions and / or data.

[0081] In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0082] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A multi-ferric core material based, high current sensor device for hundreds of kA impulse currents, comprising: Multi-composite magnetic core frame, multi-turn current-wound coil, at least one parallel resistor and shielding shell; The multi-composite magnetic core frame is made of at least two kinds of magnetic materials, the multi-turn current winding coil is distributed on the multi-composite magnetic core frame, the parallel resistor is connected to both ends of the multi-turn current winding coil, and the shielding shell is located on the outside of the multi-composite magnetic core frame. The conductor carrying the current to be measured passes through the multi-composite magnetic core skeleton axially, and the measurement output terminal of the multi-turn current winding coil is connected to the output circuit.

2. The 100kA impulse high-current sensing device based on multi-composite magnetic core material according to claim 1, wherein, The multi-turn current-wound coils are formed in multiple segments and distributed on the multi-composite magnetic core skeleton, and the multiple groups of current-wound coils are connected in series.

3. The multi-composite magnetic core material based hundreds of kA impulse high current sensing device according to claim 2, wherein, Each of the multiple sets of current-wound coils has one of the at least one parallel resistors connected to its two ends.

4. The multi-compound magnetic core material based, hundreds of kA impulse high current sensing device according to any one of claims 1 to 3, wherein, The multi-composite magnetic core frame is composed of magnetic laminations made of at least two materials, and the thickness of each layer of magnetic laminations is less than or equal to 10 μm.

5. The multi-composite magnetic core material based hundreds of kA impulse high current sensing device according to claim 4, wherein, In the at least two types of magnetic laminations, the magnetic laminations of each material are symmetrically distributed along the axial direction of the multi-composite magnetic core skeleton.

6. The multi-compound magnetic core material based, hundreds of kA impulse high current sensing device according to any one of claims 1 to 5, wherein, The shielding shell includes a low-frequency magnetic shielding shell, a high-frequency magnetic shielding shell, and an electrical shielding shell. The low-frequency magnetic shielding shell is used to shield low-frequency magnetic field interference signals within 1MHz, and the high-frequency magnetic shielding shell is used to shield high-frequency magnetic field interference signals above 1MHz.

7. The multi-composite magnetic core material based hundreds of kA impulse high current sensing device according to claim 6, wherein, The high-frequency magnetic shielding shell is located between the low-frequency magnetic shielding shell and the electrical shielding shell, with the electrical shielding shell being the outermost layer.

8. The multi-compound magnetic core material based, hundreds of kA impulse high current sensing device according to any one of claims 1 to 7, wherein, The multi-composite magnetic core skeleton is wrapped with an insulating layer, and the multi-turn current-wound coil is wrapped with an insulating layer.

9. The 100kA impulse high-current sensing device based on multi-composite magnetic core material according to any one of claims 1 to 8, wherein, The magnetic materials of the multi-composite magnetic core skeleton include: ferrite, microcrystalline alloy, and permalloy.

10. A design method for a 100kA impulse high-current sensing device based on multi-composite magnetic core materials, used to obtain a 100kA impulse high-current sensing device based on multi-composite magnetic core materials according to any one of claims 1 to 9, wherein, The method includes: Calculate the ampere-seconds of the current waveform under test based on the parameters of the current waveform under test; Calculate the bandwidth requirement based on the frequency content of the current waveform to be measured; Based on the bandwidth requirements, determine the proportion and stacking method of each material in the multi-composite magnetic core material; The dimensions of the multi-composite magnetic core frame are determined based on the ampere-second count of the current waveform under test and the parameters of the multi-composite magnetic core material. The magnetic saturation characteristics of the multi-composite magnetic core skeleton were tested to obtain the BH curve of the multi-composite magnetic core skeleton. Using the sensitivity, upper cutoff frequency, lower cutoff frequency, winding resistance, and heat generation of the current sensing device as constraints, the winding wire diameter, number of turns, and number of segment groups of the current winding coil are determined. Calculate the grouped induced voltage, inter-turn capacitance, equivalent inductance, and capacitance to ground of the current-wound coil, and verify its rationality. Once the rationality verification is passed, the reliable operating range of the pulse current coil is determined based on the parameters of the current sensing device.

11. A computer readable storage medium, wherein, The computer-readable storage medium stores a computer program that, when run on a computer, causes the computer to perform the method according to claim 10.

12. An electronic device comprising: Memory and processor; The memory is used to store computer programs that can be executed by the processor; The processor executes the computer program to execute the method according to claim 10.

Images