An anti-interference pulsed inductance intensity measuring device and measuring method

Abstract

The application relates to the technical field of electric induction measuring devices, in particular to an anti-interference pulse inductance intensity measuring device and a measuring method, which comprises a machine case, a measuring isolation cabin, a control and measuring circuit unit and a test interface; the measuring isolation cabin is installed in the machine case through a damping assembly, high-precision current sensors and high-precision voltage sensors are arranged in the measuring isolation cabin; the test interface is installed on the side wall of the measuring isolation cabin, the inner side of the test interface is connected with the sensors, and the outer side of the test interface is connected with a to-be-measured inductance located outside the measuring isolation cabin through a test cable; the signal output end of the sensor is connected with a signal processing module through a special shielding lead structure penetrating the wall surface of the measuring isolation cabin; through the cooperative design of the cabin structure, a composite shielding layer, a directional heat conduction structure, air-suspended vibration isolation and a wall-penetrating filter structure, electromagnetic, heat and vibration interference are isolated, and high-precision and high-repetitive pulse inductance measurement is realized.

Description

Technical Field

[0001] This invention relates to the field of inductance measurement equipment technology, specifically to an anti-interference pulse inductance strength measuring device and method. Background Technology

[0002] Pulsed inductance measurement devices are key testing equipment in the fields of power electronics, new energy, and precision instruments. They are mainly used to measure the dynamic inductance value of inductors under high current or pulsed operating conditions. Unlike the traditional AC bridge method, which measures under static small signals, this device simulates the real operating conditions by applying a controllable short-duration high voltage or high current pulse to the inductor under test, thereby obtaining key characteristic parameters of the inductor when it is approaching or entering the magnetic saturation range. However, the nature of pulsed measurement determines the transient, weak, and high rate of change characteristics of its signal, which makes the measurement process highly susceptible to various interferences. Factors such as electromagnetic radiation, contact resistance fluctuations, lead inductive coupling, environmental vibration, and temperature drift can all directly superimpose or distort the measured signal, leading to decreased measurement accuracy, poor repeatability, and in severe cases, even failure to obtain effective data.

[0003] Currently, the anti-interference design of pulse inductance measurement devices mainly focuses on electrical optimization and software compensation. In circuit design, the Kelvin four-wire detection method is commonly used to separate the excitation and measurement circuits, reducing the influence of contact resistance and lead resistance. Some high-end devices introduce adaptive oscillator circuits to convert inductance into frequency signals for measurement, reducing the absolute dependence on the integrity of analog signals. In signal processing, the acquired current and voltage waveforms are typically post-processed using digital filtering, multiple averaging, and nonlinear curve fitting to extract ideal signal features from noisy data. In environmental control, precision measurements often place the entire device or the inductor under test in an external shielded box or shielded room, with strict temperature and humidity control within the laboratory. For example, patent application CN202010364969.2 discloses an inductor DC bias current source testing device. This solution focuses on the DC bias current source testing scenario for inductors, which is susceptible to interference from current noise and electromagnetic coupling during testing. Its anti-interference design centers on signal filtering and basic shielding.

[0004] However, the above solutions still have the following inherent drawbacks: existing technologies mainly focus on dealing with existing interference rather than preventing its generation and intrusion; circuit optimization and software filtering have limited effectiveness against near-field coupling interference between strong radiation sources and sensitive circuits in physical space; and as measurement accuracy continues to improve, the anti-interference capability of electrical means has approached its physical limit. In addition, the reliance on external shielding boxes or strict laboratory environments makes the equipment bulky, heavy, and inconvenient to carry, and the testing process is cumbersome, making it difficult to integrate into automated production lines or use for rapid on-site testing. This results in the measurement reference of the device itself being in an unstable physical state, and subsequent electrical optimization and software compensation cannot fundamentally solve the problems of measurement accuracy and repeatability. Summary of the Invention

[0005] The purpose of this invention is to provide an anti-interference pulse inductance strength measuring device and method, so as to solve the problem that the measurement reference of the existing anti-interference pulse inductance strength measuring device is itself in an unstable physical state, and subsequent electrical optimization and software compensation cannot fundamentally solve the problems of measurement accuracy and repeatability.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] An anti-interference pulsed inductance strength measuring device and method are disclosed, comprising a chassis, a human-machine interface panel, a measurement isolation chamber, a control and measurement circuit unit, and a power supply module. The human-machine interface panel is mounted on the front face of the chassis. The measurement isolation chamber is mounted inside the chassis via a shock-absorbing component. The control and measurement circuit unit is mounted inside the chassis and includes a pulse generation and power drive module, a signal processing module, a high-precision current sensor, and a high-precision voltage sensor. Both the high-precision current sensor and the high-precision voltage sensor are housed within the measurement isolation chamber. A test interface is installed on the side wall of the measurement isolation chamber, and the inner side of the test interface is connected to the high-precision voltage sensor. The output of the current sensor and the input of the high-precision voltage sensor are electrically connected. The outside of the test interface is connected to the inductor under test via a test cable. The signal outputs of the high-precision current sensor and the high-precision voltage sensor penetrate the wall of the measurement isolation chamber through a dedicated shielded lead structure and are connected to the signal processing module. This scheme physically isolates the most core and sensitive analog front-end components of the measurement link, the high-precision current sensor and the high-precision voltage sensor, inside an independent measurement isolation chamber. The pulse generation and power drive module, which generates strong electromagnetic interference and high heat, and the signal processing module, which is responsible for weak signal processing, are all located in the chassis space outside the measurement isolation chamber. At the same time, the inductor under test does not enter the measurement isolation chamber, but is connected remotely through a test interface installed on the side wall of the chamber and an external test cable. The above layout forms a clear three-level spatial partition at the overall system level: the innermost layer is the measurement isolation chamber that houses the sensors, forming a controlled microenvironment that integrates electromagnetic, thermal, and mechanical elements; the middle layer is the area inside the chassis and outside the measurement isolation chamber, used to arrange various interference sources and auxiliary functional units; the outermost layer is the chassis shell, which undertakes primary protection and overall system integration functions.

[0008] Unlike traditional solutions that rely on post-processing methods such as circuit filtering and software compensation, this solution starts from the top-level design of the mechanical structure, sacrificing space for signal-to-noise ratio and replacing electrical remedies with physical isolation. The shared sensor compartment ensures the consistency of current and voltage measurement channels; the centralized layout of test interfaces reduces wall penetrations, providing a prerequisite for shielding integrity; and the vibration damping components are suspended within the compartment, further isolating environmental vibrations. The synergistic effect of these designs enables the interference-resistant pulse inductance strength measurement device to achieve high-precision, high-repeatability pulse inductance measurement without the need for an external shielded anechoic chamber or harsh laboratory conditions. This provides an innovative solution with a simple structure, controllable cost, and strong environmental adaptability for fields such as power electronics and new energy.

[0009] Preferably, the measurement isolation chamber is a three-layer composite shielding structure consisting of an outermost layer, a middle layer, and an innermost layer. The innermost layer is a highly conductive metal layer, made of any one of copper, aluminum, silver, silver-plated copper plate, or their alloys. The middle layer is a radio frequency absorbing material layer, made of any one of carbonyl iron powder, ferrite, conductive foam, or composite absorbing rubber. The outermost layer is a structural support and grounding layer. The outermost, middle, and innermost layers are isolated by insulating gaskets, and the innermost and outermost layers each have independent single-point grounding terminals. This three-layer composite structure design first utilizes the eddy current effect of the innermost highly conductive metal layer to rapidly attenuate external high-frequency electromagnetic interference. The selection of materials can be flexibly adjusted according to the electromagnetic environment requirements of the actual application scenario. For example, in areas with strong electromagnetic interference, silver or silver-plated copper plates with better conductivity can be used to improve shielding effectiveness. The radio frequency absorbing material in the middle layer absorbs and converts residual interference signals that penetrate the inner metal layer, transforming electromagnetic energy into heat dissipation. Different absorbing materials have different absorption efficiencies for specific frequency bands. For example, carbonyl iron powder is suitable for the low and medium frequency bands, while ferrite performs better in the high frequency band. Targeted selection can be made according to the main interference frequency range. The outermost structural support and grounding layer not only provides a stable mechanical load for the entire cabin, but its independent single-point grounding design can effectively discharge the interference charge induced on the cabin surface to the ground quickly, avoiding charge accumulation and the formation of secondary interference sources. The setting of insulating gaskets prevents electrochemical corrosion caused by contact between layers and additional interference paths caused by potential differences between different materials. This ensures that the three-layer shielding structure can not only work together to resist interference, but also maintain the independence and stability of each function, further improving the adaptability of the measurement isolation cabin to complex electromagnetic environments.

[0010] Preferably, the outer surface of the innermost layer of the measurement isolation chamber is provided with an integrated heat-conducting fin array. The heat-conducting fin array is flat, with one end connected to the outer surface of the innermost layer and the other end passing through pre-set heat insulation holes on the middle and outermost layers and extending to the outside of the measurement isolation chamber. An active heat sink is installed on the rear end face of the inner sidewall of the chassis, and heat dissipation holes are opened at the position corresponding to the active heat sink on the rear end face of the chassis. The installation position of the active heat sink is aligned with the position of the heat-conducting fin array. A heat-conducting medium is installed between the bottom of the high-precision current sensor and the high-precision voltage sensor and the inner surface of the innermost layer. An integrated flat-shaped heat-conducting fin array is provided on the outer surface of the innermost layer of the measurement isolation chamber, and it extends through the pre-set heat insulation holes to the outside of the chamber and is aligned and coupled with the active heat sink. At the same time, a heat-conducting medium is filled between the bottom of the sensor and the inner surface of the innermost layer, forming a directional heat flow channel with low thermal resistance, high directionality, and no damage to the shielding integrity. This design avoids the problems of heat accumulation, sensor temperature drift, and decreased measurement accuracy caused by the sealing of traditional shielded cavities. At the same time, it avoids the technical contradiction of opening large-area ventilation openings in the cabin wall for heat dissipation, which would seriously degrade the shielding effectiveness. Through the slit-type heat-exit structure of the heat insulation holes and the directional heat conduction of the fin array, the heat source inside the cabin is discharged non-contactly while maintaining the integrity of the broadband electromagnetic shielding of the cabin. This ensures that the high-precision current sensor and voltage sensor always operate in a stable thermal environment with constant temperature and no thermal drift, thereby ensuring the measurement repeatability, data comparability, and long-term operational reliability of the pulse inductance measurement device under long-term continuous working conditions.

[0011] Furthermore, this design fully considers the synergistic optimization of electromagnetic compatibility and thermal management. By precisely aligning the heat-conducting fin array with the active heat sink, and combining the efficient thermal conductivity of the heat-conducting medium, the heat generated by the sensor inside the chamber can be quickly and directionally transferred to the external cooling system, effectively reducing the fluctuation range of the sensor's operating temperature. This directional heat flow channel construction solves the technical challenge of balancing heat dissipation and shielding in traditional shielding structures. It also reduces energy loss during heat transfer through an integrated structural design, improving overall heat dissipation efficiency. Moreover, the slit-type heat insulation hole design ensures that the fin array can pass through while minimizing the impact on the electromagnetic shielding performance of the measurement isolation chamber. This ensures that the anti-interference pulse inductance strength measurement device maintains stable measurement accuracy even in complex electromagnetic environments, providing a reliable temperature environment guarantee for pulse inductance strength measurement.

[0012] Preferably, the vibration damping assembly includes a low-frequency damping airbag and a mechanical limiting post. The low-frequency damping airbag is installed between the outermost layer of the measurement isolation chamber and the chassis. The mechanical limiting post is fixed to the bottom of the chassis and extends vertically upwards, with its top slidably connected to the bottom surface of the outermost layer of the measurement isolation chamber. The low-frequency damping airbag is filled with highly elastic gas, which can absorb low-frequency vibration energy transmitted from the outside through gas compression and expansion, effectively attenuating the impact and bumps experienced by the measuring device during transportation or operation. The mechanical limiting post serves as a guide and limiter, with its top embedded in a pre-set groove on the bottom surface of the measurement isolation chamber. When the device undergoes horizontal displacement, the limiting post can restrict excessive shaking of the chamber, preventing collisions between the internal sensor and other components due to excessive displacement. Working together, the low-frequency damping airbag buffers vertical vibrations, while the mechanical limiting post constrains horizontal displacement, providing comprehensive vibration damping protection for the measurement isolation chamber and further ensuring the measurement accuracy of the high-precision sensor in vibration environments.

[0013] Preferably, the measuring isolation chamber is externally fitted with a heat dissipation duct. The heat dissipation duct has an annular structure, and an annular cavity is formed between the inner wall of the heat dissipation duct and the outer wall of the measuring isolation chamber. The fins of the heat-conducting fin array extend into the annular cavity. An air inlet and an air outlet are provided on the side wall of the heat dissipation duct. The air inlet is located at the end of the heat dissipation duct near the human-machine interface panel, and the air outlet is located at the end of the heat dissipation duct near the active radiator. When the device is running, the negative pressure generated by the active radiator will draw in external cold air from the air inlet. The cold air will come into full contact with the heat-conducting fin array in the annular cavity, absorbing the heat transferred from the measuring isolation chamber. The air carrying the heat will then be discharged from the air outlet. The fins of the heat-conducting fin array extending into the annular cavity increase the contact area with the air and significantly improve the heat exchange efficiency. This annular cooling duct design allows cool air to flow evenly along the outer perimeter of the measurement isolation chamber, preventing localized heat accumulation and ensuring that the temperature inside the measurement isolation chamber remains within a suitable range for sensor operation. This further ensures the stability and measurement accuracy of the measuring device during long-term operation.

[0014] Preferably, the dedicated shielded lead structure includes a metal housing and multiple feedthrough capacitors. The metal housing is mounted on the side wall of the measurement isolation chamber near the air inlet. The multiple feedthrough capacitors are located at the center of the metal housing. A π-type filter circuit board is installed inside the chassis. The signal lines of the high-precision current sensor and the high-precision voltage sensor are electrically connected to the input terminal of the π-type filter circuit board through the multiple feedthrough capacitors. The output terminal of the π-type filter circuit board is electrically connected to the signal processing module through a shielded twisted-pair cable. The metal housing provides physical protection for the feedthrough capacitors and further blocks external electromagnetic interference from entering the measurement isolation chamber through the leads. The multiple feedthrough capacitors can filter out interference signals of different frequencies, and their capacitance values ​​are precisely matched to effectively suppress high-frequency noise. The π-type filter circuit board, based on the initial filtering by the feedthrough capacitors, forms a secondary filter network through a combination of capacitors and inductors to further attenuate residual interference components in the signal lines. The outer metal shielding layer of the shielded twisted pair cable is reliably connected to the metal casing and the outer shell of the chassis, forming a complete grounding shielding path to prevent the signal from being affected by external electromagnetic radiation during transmission. This multi-layered shielding and filtering design ensures that the original signals output by the high-precision current sensor and the high-precision voltage sensor have extremely high purity, providing a reliable guarantee for the subsequent signal processing module to perform accurate pulse inductance strength measurement.

[0015] It is worth noting that the metal casing is specifically mounted on the side wall of the measurement isolation chamber near the air inlet. During operation, the negative pressure generated by the active heat sink draws in external cold air from the air inlet, and the low-temperature airflow preferentially flows over the surface of the metal casing in this side wall area. As the carrier and partial shield of the feedthrough capacitor, the metal casing itself generates a small amount of Joule heat during the conduction and interference discharge process due to the skin effect of high-frequency current and dielectric loss. This arrangement places the metal casing at the air inlet end, where the temperature is lowest and the flow rate is fastest in the entire heat dissipation channel. Cold air directly forces convection cooling onto its surface, effectively suppressing the temperature rise of the feedthrough capacitor and surrounding circuits, avoiding capacitance drift and filter characteristic degradation caused by local overheating, thus ensuring the long-term thermal stability of the filtering performance. This guarantees the long-term stability of the anti-interference pulse inductance strength measurement device.

[0016] Preferably, an electromagnetic sealing gasket is used to install between the metal housing and the wall of the measurement isolation chamber. The electromagnetic sealing gasket is made of a conductive elastic material, and its internal metal wires or conductive particles effectively fill the gap between the metal housing and the chamber wall, forming a continuous conductive path and thus eliminating electromagnetic leakage at the gap. During installation, the gasket is uniformly compressed to ensure a tight fit with the contact surface, maintaining stable shielding performance even under long-term use or vibration environments. This sealing method not only blocks external electromagnetic interference from entering through the gap but also prevents electromagnetic radiation generated by the internal circuitry from leaking outwards, further improving the electromagnetic compatibility of the entire measuring device and creating a cleaner electromagnetic environment for high-precision inductance measurement.

[0017] The present invention also provides a pulsed inductance strength measurement method for interference suppression as described above, comprising the following steps:

[0018] S1: System initialization and self-test steps: The device is powered on, the control unit executes the self-test program to confirm that the status of each functional module is normal; the active heat sink is started to make the interior of the measurement isolation chamber reach and stabilize at the preset working temperature;

[0019] S2: Establishing a measurement connection: Connect the inductor to be tested to the test interface on the side wall of the measurement isolation chamber through the test cable. After the connection is confirmed, the system reads the contact status feedback signal.

[0020] S3: Silent Stabilization and Interference Suppression Steps: After the measurement connection is established, the system enters a silent waiting period of a preset duration; at this time, the low-frequency damping airbag isolates the micro-vibrations transmitted by the environment, and the top of the mechanical limit column maintains a sliding connection with the bottom surface of the outermost layer of the measurement isolation chamber; at the same time, the electromagnetic environment inside the measurement isolation chamber tends to stabilize, and the high-precision current sensor and high-precision voltage sensor complete the preheating drift convergence.

[0021] S4: Pulse application and synchronous sampling steps: The pulse generation and power drive module of the control and measurement circuit unit generates a single high-voltage pulse with controllable parameters, which is applied to the inductor under test through the test cable; the high-precision current sensor and high-precision voltage sensor set in the measurement isolation chamber are triggered synchronously to collect the transient current and voltage data across the inductor during the pulse.

[0022] S5: Data Processing and Completion Steps: The signal processing module processes the acquired raw data and calculates the inductance strength based on the relationship between voltage and current change rates; the measured data is stored or output; after completion, the system remains in standby mode, waiting for the next measurement connection.

[0023] By means of the above-described solution, the present invention has at least the following advantages:

[0024] 1. This invention employs an anti-interference architecture with separate internal and external placement and integrated chambers. It physically isolates the high-precision current sensor and the high-precision voltage sensor within independent measurement isolation chambers, while placing the strong interference source pulse generation and power drive module and signal processing module in the external chassis space. This avoids the fundamental problems of severe near-field radiation coupling, degraded shielding effectiveness, and limited signal-to-noise ratio improvement caused by traditional solutions where the sensor and interference source are located in the same chamber and rely on circuit filtering and software compensation for post-processing. This ensures that the anti-interference pulse inductance strength measurement device possesses core measurement performance of high precision, high repeatability, and strong environmental adaptability without the need for an external shielded anechoic chamber or harsh laboratory environment.

[0025] 2. This invention constructs an integrated thermally conductive fin array on the outermost surface of the innermost layer of the measurement isolation chamber, extending it through heat insulation holes to the outside of the chamber and thermally coupling it with the active heat sink. Simultaneously, a thermally conductive medium is filled between the bottom of the sensor and the inner wall of the chamber, creating a directional heat flow channel with low thermal resistance, high directionality, and without compromising shielding integrity. This avoids the technical contradictions of traditional shielded cavities, such as heat accumulation, sensor temperature drift, and decreased measurement accuracy due to airtightness, as well as the serious deterioration of shielding effectiveness caused by opening large-area ventilation openings in the chamber wall for heat dissipation. It ensures the measurement repeatability, data comparability, and long-term operational reliability of the anti-interference pulse inductance strength measurement device under long-term continuous working conditions.

[0026] 3. This invention utilizes a shock-absorbing component consisting of a low-frequency damping airbag and a mechanical limiting post, placed between the measurement isolation chamber and the chassis. The airbag's low natural frequency characteristics isolate wide-band micro-vibrations in the environment, while the sliding connection structure of the limiting post provides guidance and failure protection for the chamber. This avoids the problems of traditional rigid connection or single-stage shock absorption schemes failing to simultaneously address high-frequency vibration isolation and impact limiting, or probe contact micro-movement and sensor baseline drift caused by vibration transmission. It ensures that the measurement isolation chamber is always in a near-static mechanical reference state, providing a stable physical platform for high-precision pulse inductance measurement.

[0027] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show a certain embodiment of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1This is a schematic diagram of the anti-interference pulse inductance strength measuring device of the present invention;

[0030] Figure 2 This is a schematic diagram of the internal installation of the anti-interference pulse inductance strength measuring device of the present invention.

[0031] Figure 3 This is a schematic diagram of the measuring isolation chamber in the anti-interference pulse inductance strength measuring device of the present invention;

[0032] Figure 4 For the present invention Figure 3 A three-dimensional sectional view;

[0033] Figure 5 For the present invention Figure 3 Sectional view at point AA;

[0034] Figure 6 For the present invention Figure 5 Sectional view at point BB;

[0035] Figure 7 For the present invention Figure 6 A magnified view of a section at point C;

[0036] Figure 8 This is a flowchart of the anti-interference pulse inductance intensity measurement method of the present invention.

[0037] In the diagram: 1. Chassis; 101. Human-Machine Interface Panel; 2. Measurement Isolation Chamber; 201. Outermost Layer; 202. Middle Layer; 203. Innermost Layer; 204. Insulating Gasket; 301. High-Precision Current Sensor; 302. High-Precision Voltage Sensor; 303. Test Interface; 4. Power Module; 501. Thermal Fin Array; 502. Active Heat Sink; 503. Thermal Conducting Medium; 601. Low-Frequency Damping Airbag; 602. Mechanical Limiting Post; 701. Heat Dissipation Air Duct; 702. Annular Cavity; 703. Air Inlet; 704. Air Outlet; 801. Metal Shell; 802. Through-Center Capacitor; 9. Electromagnetic Sealing Gasket. Detailed Implementation

[0038] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0039] Please see Figures 1 to 8 This invention provides an anti-interference pulse inductance strength measuring device and method, the technical solution of which is as follows:

[0040] Please refer to the section on an interference-resistant pulsed inductance strength measuring device and method. Figures 1 to 8The system includes a chassis 1, a human-machine interface panel 101, a measurement isolation chamber 2, a control and measurement circuit unit, and a power module 4. The human-machine interface panel 101 is mounted on the front face of the chassis 1. The measurement isolation chamber 2 is mounted inside the chassis 1 via a shock-absorbing assembly. The control and measurement circuit unit is mounted inside the chassis 1 and includes a pulse generation and power drive module, a signal processing module, a high-precision current sensor 301, and a high-precision voltage sensor 302. Both the high-precision current sensor 301 and the high-precision voltage sensor 302 are located inside the measurement isolation chamber 2. A test interface 303 is mounted on the side wall of the measurement isolation chamber 2. The inner side of the test interface 303 is connected to the output terminal of the high-precision current sensor 301 and the high-precision voltage sensor 4. The input terminal of the pressure sensor 302 is electrically connected. The outside of the test interface 303 is connected to the inductor under test via a test cable. The signal output terminals of the high-precision current sensor 301 and the high-precision voltage sensor 302 penetrate the wall of the measurement isolation chamber 2 through a dedicated shielded lead structure and are connected to the signal processing module. The measurement isolation chamber 2 is a three-layer composite shielding structure consisting of an outermost layer 201, a middle layer 202, and an innermost layer 203. The innermost layer 203 is a high-conductivity silver-plated copper plate layer, the middle layer 202 is a ferrite radio frequency absorbing material layer, and the outermost layer 201 is a structural support and grounding layer. The outermost layer 201, the middle layer 202, and the innermost layer 203 are isolated by an insulating gasket 204, and the innermost layer 203 and the outermost layer 201 are respectively provided with It has an independent single-point grounding terminal. The shock absorption assembly includes a low-frequency damping airbag 601 and a mechanical limiting post 602. The low-frequency damping airbag 601 is installed between the outermost layer 201 of the measurement isolation chamber 2 and the chassis 1. The mechanical limiting post 602 is fixed to the bottom of the chassis 1 and extends vertically upward. The top of the mechanical limiting post 602 is slidably connected to the bottom surface of the outermost layer 201 of the measurement isolation chamber 2. An integrated heat-conducting fin array 501 is provided on the outer surface of the innermost layer 203 of the measurement isolation chamber 2. The heat-conducting fin array 501 is flat. One end of the heat-conducting fin array 501 is connected to the outer surface of the innermost layer 203, and the other end passes through the pre-set heat insulation holes on the intermediate layer 202 and the outermost layer 201 and extends to the outside of the measurement isolation chamber 2. The inner wall of the chassis 1 An active heat sink 502 is installed on the rear end face of the chassis 1, and heat dissipation holes are opened at the position corresponding to the active heat sink 502 on the rear end face of the chassis 1. The installation position of the active heat sink 502 is aligned with the position of the heat-conducting fin array 501. A heat-conducting medium 503 is installed between the bottom of the high-precision current sensor 301 and the high-precision voltage sensor 302 and the inner surface of the innermost layer 203. A heat dissipation duct 701 is fitted on the outside of the measurement isolation chamber 2. The heat dissipation duct 701 has a ring structure. An annular cavity 702 is formed between the inner wall of the heat dissipation duct 701 and the outer wall of the measurement isolation chamber 2. The fin portion of the heat-conducting fin array 501 extends into the annular cavity 702. An air inlet 703 and an air outlet 704 are opened on the side wall of the heat dissipation duct 701.An air inlet 703 is located at one end of the heat dissipation duct 701 near the human-machine interface panel 101, and an air outlet 704 is located at one end of the heat dissipation duct 701 near the active heat sink 502. The dedicated shielded lead structure includes a metal housing 801 and multiple through-hole capacitors 802. The metal housing 801 is mounted on the side wall of the measurement isolation chamber 2 near the air inlet 703. The multiple through-hole capacitors 802 are located at the center of the metal housing 801. A π-type filter circuit board is installed inside the chassis 1. The signal lines of the high-precision current sensor 301 and the high-precision voltage sensor 302 are electrically connected to the input terminal of the π-type filter circuit board through the multiple through-hole capacitors 802. The output terminal of the π-type filter circuit board is electrically connected to the signal processing module through a shielded twisted-pair cable. An electromagnetic sealing gasket 9 is used between the metal housing 801 and the wall of the measurement isolation chamber 2.

[0041] The working principle of this invention is as follows:

[0042] Please see Figures 1 to 8 The operator first connects the device to the power supply, and the system performs a power-on self-test. The control unit executes the initialization program, sequentially confirming that the pulse generation and power drive module, signal processing module, high-precision current sensor 301, high-precision voltage sensor 302, active heat sink 502, and all electrical connections are normal. At the same time, the control unit loads preset measurement parameters, including pulse amplitude, pulse width, bias current, sampling frequency, and averaging count.

[0043] The active radiator 502 starts operating at low speed, and the temperature control system inside the measurement isolation chamber 2 begins to work. A temperature sensor located on the inner wall of the chamber monitors the ambient temperature in real time, and the control unit automatically adjusts the rotation speed of the active radiator 502 and the airflow rate of the cooling duct 701 according to the preset operating temperature threshold. The heat-conducting medium 503 rapidly conducts the minute Joule heat generated at the bottom of the high-precision current sensor 301 and the high-precision voltage sensor 302 to the innermost metal wall 203 of the chamber, and then directs it through the integrated heat-conducting fin array 501 into the annular cavity 702. The cooling airflow is drawn in through the air inlet 703, carries heat across the fin surface, and is then discharged from the air outlet 704, allowing the measurement isolation chamber 2 to quickly reach and stably maintain a preset constant temperature. Meanwhile, the low-frequency damping airbag 601 carries the measurement isolation chamber 2 suspended inside the chassis 1, effectively isolating broadband micro-vibrations introduced by environmental factors such as ground conduction, fan operation and personnel movement. The top of the mechanical limit column 602 is slidably connected to the bottom surface of the chamber, providing vertical guidance and horizontal limit protection, ensuring that the chamber is in a near-static mechanical reference state during the silent waiting period.

[0044] After the system self-test passes, the temperature stabilizes, and the vibration decays and converges, the human-machine interface panel 101 displays a ready status. The operator connects the inductor under test to the test interface 303 on the side wall of the measurement isolation chamber 2 via a test cable. The interface is pre-wired to the output terminal of the high-precision current sensor 301 and the input terminal of the high-precision voltage sensor 302. The distal end of the test cable is reliably connected to the inductor pins using a four-terminal Kelvin test clip or a dedicated probe adapter. The control unit reads the contact status feedback signal. After confirming that the connection is correct, the operator triggers the measurement command through the human-machine interface panel 101.

[0045] After the measurement command is issued, the control unit drives the pulse generator and the power drive module to generate a single high-voltage pulse with controllable parameters. This pulse current is applied to the inductor under test via the test cable, and the high-precision current sensor 301 and the high-precision voltage sensor 302 are simultaneously triggered. The current sensor adopts a through-hole structure, with the measured current flowing from inside the chamber through the sensor's central hole and then output to the inductor outside the chamber, achieving non-invasive sampling. The voltage sensor acquires the transient voltage waveform across the inductor in real time. The original analog signals output by the two sensors are directly soldered to the inner end of the through-hole capacitor 802 in the dedicated shielded lead structure via signal lines, and high-frequency interference components are discharged to the chamber ground nearby. The residual signal enters the π-type filter circuit board through the outer end of the through-hole capacitor 802, and undergoes secondary filtering through the capacitor and inductor combination network to further attenuate conducted noise. The purified signal is transmitted to the signal processing module via a shielded twisted pair cable.

[0046] The signal processing module performs high-speed analog-to-digital conversion on the acquired transient current and voltage data, and calculates the ratio of voltage to current change rate based on the law of electromagnetic induction, thereby calculating the dynamic inductance value of the inductor under test in real time. The control unit compares the measurement results with preset thresholds, automatically determines whether the inductance strength is qualified, and stores the data in the internal memory or exports it to the host computer via the communication interface. The entire pulse application and sampling process is completed within tens of microseconds to milliseconds, during which the measurement isolation chamber 2 maintains a multi-controlled state of electromagnetic silence, thermal stability, and mechanical stillness.

[0047] After the measurement is completed, the operator disconnects the test cable from the test interface 303, breaking the connection with the inductor under test. The device automatically resets to standby mode, the active heat sink 502 continues to operate at low speed to maintain a constant temperature inside the chamber, and the low-frequency damping airbag 601 continues to bear the suspension and isolation vibration of the chamber, awaiting the next measurement task. Under long-term continuous working conditions, the above process can be repeated cyclically without opening the maintenance door of the measurement isolation chamber 2. The door is only opened by professionals in maintenance scenarios such as equipment debugging, fault diagnosis, or periodic calibration. The entire working process achieves high-precision, high-repeatability, and high-environmental adaptability automatic measurement of pulse inductance strength through the synergistic effect of the separate internal and external chamber structure, the directional heat conduction and non-intrusive temperature control, the air suspension vibration isolation mechanical reference, and the multi-stage purification signal through-wall design.

[0048] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An anti-interference pulse-type inductance strength measuring device, characterized in that, The system includes a chassis (1), a human-machine interface panel (101), a measurement isolation chamber (2), a control and measurement circuit unit, and a power module (4). The human-machine interface panel (101) is mounted on the front surface of the chassis (1). The measurement isolation chamber (2) is mounted inside the chassis (1) via a shock-absorbing assembly. The control and measurement circuit unit is mounted inside the chassis (1). The control and measurement circuit unit includes a pulse generation and power drive module, a signal processing module, a high-precision current sensor (301), and a high-precision voltage sensor (302). The high-precision current sensor (301) and the high-precision voltage sensor (302) are connected in series. The sensors (302) are all installed inside the measurement isolation chamber (2). The side wall of the measurement isolation chamber (2) is equipped with a test interface (303). The inner side of the test interface (303) is electrically connected to the output end of the high-precision current sensor (301) and the input end of the high-precision voltage sensor (302). The outer side of the test interface (303) is connected to the inductor under test through a test cable. The signal output ends of the high-precision current sensor (301) and the high-precision voltage sensor (302) penetrate the wall of the measurement isolation chamber (2) through a special shielded lead structure and are connected to the signal processing module. The measurement isolation chamber (2) is a three-layer composite shielding structure consisting of an outermost layer (201), a middle layer (202), and an innermost layer (203). The innermost layer (203) is a metal layer with high conductivity. The innermost layer (203) is made of any one of the following materials: copper, aluminum, silver, silver-plated copper plate, or their alloys. The middle layer (202) is a radio frequency absorbing material layer. The middle layer (202) is made of any one of the following materials: carbonyl iron powder, ferrite, conductive foam, or composite absorbing rubber. The outermost layer (201) is a structural support and grounding layer. The outermost layer (201), the middle layer (202), and the innermost layer (203) are isolated by an insulating pad (204). An integrated heat-conducting fin array (501) is provided on the outer surface of the innermost layer (203) of the measurement isolation chamber (2). The heat-conducting fin array (501) is flat. One end of the heat-conducting fin array (501) is connected to the outer surface of the innermost layer (203), and the other end passes through the heat insulation holes preset on the middle layer (202) and the outermost layer (201) and extends to the outside of the measurement isolation chamber (2). An active heat sink (502) is installed on the rear end face of the inner side wall of the chassis (1), and a heat dissipation hole is opened at the position corresponding to the active heat sink (502) on the rear end face of the chassis (1). The installation position of the active heat sink (502) is aligned with the position of the heat-conducting fin array (501). A heat-conducting medium (503) is installed between the bottom of the high-precision current sensor (301) and the high-precision voltage sensor (302) and the inner surface of the innermost layer (203).

2. The anti-interference pulse inductance strength measuring device according to claim 1, characterized in that: The shock absorption assembly includes a low-frequency damping airbag (601) and a mechanical limiting post (602). The low-frequency damping airbag (601) is installed between the outermost layer (201) of the measurement isolation chamber (2) and the chassis (1). The mechanical limiting post (602) is fixed to the bottom of the chassis (1) and extends vertically upward. The top of the mechanical limiting post (602) is slidably connected to the bottom surface of the outermost layer (201) of the measurement isolation chamber (2).

3. The anti-interference pulse inductance strength measuring device according to claim 1, characterized in that: The measurement isolation chamber (2) is fitted with a heat dissipation duct (701) on the outside. The heat dissipation duct (701) has an annular structure. An annular cavity (702) is formed between the inner wall of the heat dissipation duct (701) and the outer wall of the measurement isolation chamber (2). The fin portion of the heat-conducting fin array (501) extends into the annular cavity (702). An air inlet (703) and an air outlet (704) are provided on the side wall of the heat dissipation duct (701). The air inlet (703) is located at one end of the heat dissipation duct (701) near the human-machine interface panel (101), and the air outlet (704) is located at one end of the heat dissipation duct (701) near the active heat sink (502).

4. The anti-interference pulse inductance strength measuring device according to claim 3, characterized in that: The dedicated shielded lead structure includes a metal housing (801) and multiple feedthrough capacitors (802). The metal housing (801) is installed on the side wall of the measurement isolation chamber (2) near the air inlet (703). The multiple feedthrough capacitors (802) are located in the center of the metal housing (801). A π-type filter circuit board is installed inside the chassis (1). The signal lines of the high-precision current sensor (301) and the high-precision voltage sensor (302) are electrically connected to the input end of the π-type filter circuit board through the multiple feedthrough capacitors (802). The output end of the π-type filter circuit board is electrically connected to the signal processing module through a shielded twisted pair cable.

5. The anti-interference pulse inductance strength measuring device according to claim 4, characterized in that: The metal casing (801) is installed with an electromagnetic sealing gasket (9) between the wall of the measurement isolation chamber (2).

6. An anti-interference pulse inductance measurement method, characterized in that: This method is applied at least to the anti-interference pulse inductance strength measuring device according to any one of claims 1 to 5, and the specific method includes: S1: System initialization and self-test steps: The device is powered on, the control unit executes the self-test program to confirm that the status of each functional module is normal; the active heat sink (502) is started, so that the interior of the measurement isolation chamber (2) reaches and stabilizes at the preset working temperature; S2: Establish measurement connection steps: Connect the inductor to be tested to the test interface (303) on the side wall of the measurement isolation chamber (2) through the test cable. After the connection is confirmed, the system reads the contact status feedback signal. S3: Silent Stabilization and Interference Suppression Steps: After the measurement connection is established, the system enters a silent waiting period of a preset duration; at this time, the low-frequency damping airbag (601) isolates the micro-vibrations transmitted by the environment, and the top of the mechanical limiting column (602) maintains a sliding connection with the bottom surface of the outermost layer (201) of the measurement isolation chamber (2); at the same time, the electromagnetic environment inside the measurement isolation chamber (2) tends to stabilize, and the high-precision current sensor (301) and the high-precision voltage sensor (302) complete the preheating drift convergence; S4: Pulse application and synchronous sampling steps: The pulse generation and power drive module of the control and measurement circuit unit generates a single high-voltage pulse with controllable parameters, which is applied to the inductor under test through the test cable; the high-precision current sensor (301) and the high-precision voltage sensor (302) set in the measurement isolation chamber (2) are synchronously triggered to collect the transient current and voltage data at both ends of the inductor during the pulse. S5: Data Processing and Completion Steps: The signal processing module processes the acquired raw data and calculates the inductance strength based on the relationship between voltage and current change rates; the measured data is stored or output; after completion, the system remains in standby mode, waiting for the next measurement connection.

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