A multi-physical field coupling permanent magnet material magnetic property measuring device and system

Abstract

The application relates to a multi-physical field coupled permanent magnet material magnetic property measuring device and system, which comprises a top plate, a temperature control execution module, a sensing monitoring system, two groups of mechanical stress loading mechanisms and two groups of auxiliary magnetic yoke displacement mechanisms which are oppositely arranged on the two sides of the top plate, a main magnetic yoke connected with the mechanical stress loading mechanism, a magnetic yoke pole head installed at the end of the main magnetic yoke, an excitation winding wound outside the main magnetic yoke, an auxiliary magnetic yoke connected with the auxiliary magnetic yoke displacement mechanism, and a closed magnetic loop formed through the butt joint of the main magnetic yoke and the auxiliary magnetic yoke. The application can adapt to permanent magnet samples with various geometric structures and materials, can not only realize the accurate characterization of static and dynamic magnetic properties, but also can carry out tests on various composite physical field working conditions such as "electromagnetic-heat", "electromagnetic-force" and "electromagnetic-heat-force", thereby providing a reliable experimental platform and data support for the characteristic evolution law research and fine design of permanent magnet materials in high-performance electrical equipment, and has high application and popularization value.

Description

Technical Field

[0001] This invention relates to the field of magnetic property testing technology for permanent magnet materials, and in particular to a multi-physics field coupled permanent magnet material magnetic property measurement device and system. Background Technology

[0002] Permanent magnet materials, due to their high magnetic energy product, excellent stability, and wide operating frequency range, are widely used in various power conversion and drive systems centered on permanent magnet motors. Especially in the fields of wind power generation and electric vehicles, permanent magnet synchronous motors, with their compact structure, high efficiency, and superior speed regulation performance, have become one of the key power components. As the core functional material of the motor, the electromagnetic properties of permanent magnets directly affect the efficiency, power density, and long-term reliability of the entire system.

[0003] In real-world operating environments, permanent magnets are typically subjected to complex conditions involving the coupling of multiple factors. On one hand, the heat generated during motor operation causes temperature increases, leading to changes in the magnetic properties of the material. On the other hand, the centrifugal load from the high-speed rotation of the rotor and the mechanical constraints generated during assembly affect the internal magnetic domain structure of the permanent magnet, thereby altering its magnetization behavior. Therefore, under the combined influence of temperature and stress fields, the magnetic properties of permanent magnet materials exhibit significant nonlinear and dynamic characteristics, posing higher demands on performance prediction and lifespan assessment in motor design.

[0004] Existing technologies have been used to conduct some research on the testing and characterization of the magnetic properties of permanent magnet materials. For example, relevant standards and specifications have stipulated methods for testing the basic magnetic properties of permanent magnet materials under steady-state conditions, which can be used to obtain key parameters such as remanence, coercivity, and maximum energy product. However, these methods are usually based on static or quasi-static conditions and are difficult to reflect the dynamic response characteristics of materials under alternating magnetic fields or actual operating excitations. In addition, some studies have attempted to introduce temperature factors by constructing test devices with heating units to measure magnetic properties under different temperature conditions, but their test structures mostly adopt fixed magnetic circuit configurations, which have strong limitations on sample size and shape, resulting in insufficient versatility and adaptability. Furthermore, in terms of multi-physics coupling, existing research mostly focuses on the influence analysis of single or a few factors, lacking systematic experimental means for the comprehensive behavior under the simultaneous action of temperature, stress, and electromagnetic excitation. Especially in simulating complex mechanical conditions such as centrifugal force and assembly stress involved in actual motor operation, existing test devices cannot realistically reproduce the corresponding working conditions, resulting in discrepancies between the obtained data and practical applications. Meanwhile, there is still a lack of high-precision, multi-dimensional experimental data to support the loss mechanism, demagnetization process and evolution law of permanent magnet materials under dynamic working conditions.

[0005] In summary, existing technologies for testing the magnetic properties of permanent magnet materials still suffer from limitations such as single testing conditions, insufficient structural adaptability, and limited multi-field coupling simulation capabilities. These limitations make it difficult to meet the demands of high-performance permanent magnet motor design for refined material modeling and performance prediction. Therefore, it is necessary to develop a comprehensive measurement platform for permanent magnet materials that integrates electromagnetic, thermal, and mechanical multi-field environmental simulation. This platform would enable a comprehensive characterization of the magnetic properties of permanent magnet materials under complex service environments, thereby providing more reliable experimental data for the optimized design of related motors and systems. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a device and system for measuring the magnetic properties of permanent magnet materials with multi-physics field coupling.

[0007] This invention is achieved through the following technical solution: A multi-physics field coupled permanent magnet material magnetic property measurement device includes a top plate, a temperature control execution module located in the middle of the top plate, a sensing and monitoring system located in the middle of the temperature control execution module, two sets of mechanical stress loading mechanisms and two sets of auxiliary magnetic yoke displacement mechanisms located opposite each other on both sides of the top plate. The line connecting the two mechanical stress loading mechanisms is perpendicular to the line connecting the two auxiliary magnetic yoke displacement mechanisms. The mechanical stress loading mechanism is connected to a main magnetic yoke. A magnetic yoke pole head is installed at the end of the main magnetic yoke. An excitation winding is wound around the main magnetic yoke. The auxiliary magnetic yoke displacement mechanism is connected to an auxiliary magnetic yoke. A closed magnetic loop is formed by the docking of the main magnetic yoke and the auxiliary magnetic yoke.

[0008] According to the above technical solution, preferably, the mechanical stress loading mechanism includes a manual displacement platform, an electric displacement platform, and a main magnetic yoke fixed connector connected to the electric displacement platform via a connecting rod. The manual displacement platform and the electric displacement platform are assembled in series and stacked. A pressure sensor is provided between the main magnetic yoke fixed connector and the connecting rod.

[0009] According to the above technical solution, preferably, the root of the main magnetic yoke is precisely embedded in the pre-set tight-fit groove of the main magnetic yoke fixing connector.

[0010] According to the above technical solution, preferably, the magnetic yoke pole head is detachably connected to the end face of the magnetic yoke by means of the slot embedding of the lower fastener and the upper fastener.

[0011] According to the above technical solution, preferably, the temperature control execution module includes a polyetheretherketone oil bath and an aluminum nitride ceramic mold located in the middle of the polyetheretherketone oil bath, and the polyetheretherketone oil bath is connected to a temperature control circulating oil storage tank.

[0012] According to the above technical solution, preferably, a rectangular slot is provided in the middle of the top plate, and a support guide groove assembly is provided below the rectangular slot, and the polyether ether ketone oil bath is inserted into the support guide groove assembly.

[0013] According to the above technical solution, preferably, the upper and lower sides of the polyetheretherketone oil bath are connected to the temperature-controlled circulating oil tank through an upper circulation quick-connect connector and a lower circulation quick-connect connector, respectively. The support guide groove assembly is provided with an oil drain interface groove, and a tee is provided in the oil drain interface groove. The upper interface of the tee is directly connected to the bottom of the polyetheretherketone oil bath through a lower circulation quick-connect connector. The middle interface of the tee is connected to the external temperature-controlled circulating oil tank. The lower interface of the tee is connected to the horizontally led-out oil drain pipe through an L-shaped adapter.

[0014] According to the above technical solution, preferably, the aluminum nitride ceramic mold is used to support the sample to be tested, and the sensing and monitoring system is integrated into the aluminum nitride ceramic mold, the sensing and monitoring system comprising: Two sets of concentric circular coils, main and auxiliary, are connected in series and reversed to achieve differential compensation and real-time cancellation of the air magnetic flux component between the sensor and the sample; H-coil, based on the principle of tangential magnetic field continuity, to obtain the internal magnetic field strength of the sample; The thermistor is designed to calculate the radial thermal resistance of the aluminum nitride ceramic mold through dual-point monitoring to verify the uniformity of the temperature field and to provide measured temperature difference compensation for the Smith prediction method.

[0015] According to the above technical solution, preferably, the surface of the top plate is provided with multiple sets of displacement and wiring guide grooves, the displacement and wiring guide grooves include a guide rail groove located below the mechanical stress loading mechanism, a sensing wire groove located below the auxiliary magnetic yoke displacement mechanism, and a winding wire groove, forming a physical spatial isolation between the strong electric excitation power line and the weak electric sensing signal line.

[0016] This application also discloses a multi-physics field coupled permanent magnet material magnetic property measurement system, including the aforementioned multi-physics field coupled permanent magnet material magnetic property measurement device and an integrated measurement circuit. The integrated measurement circuit includes an industrial computer, an NI data acquisition card, a bipolar programmable high-power DC source, a wideband high-power amplifier, a circuit protection system, a reactive power compensation capacitive reactance matching group, a B / J signal differential processing circuit, an H signal differential processing circuit, a gaussmeter, a displacement control system, a mechanical stress control system, and a temperature control system.

[0017] The beneficial effects of this invention are: This invention achieves comprehensive characterization of the magnetic properties of permanent magnet materials under complex service environments by constructing a highly stable structural framework and an adjustable closed magnetic circuit system, combined with a multi-closed-loop collaborative control mechanism involving electromagnetic excitation, temperature regulation, and mechanical stress loading. The device is adaptable to permanent magnet test samples of different geometries, sizes, and material types, and can meet the testing requirements of various sample types without changing the core testing platform, significantly improving the versatility and applicability of the testing system. Simultaneously, through the coupled loading and precise control of electromagnetic, temperature, and stress fields, various operating conditions such as "electromagnetic-thermal," "electromagnetic-force," and "electromagnetic-thermal-force" can be simulated individually or in combination. This allows for a realistic reflection of the evolution of the magnetic properties of permanent magnet materials under actual operating conditions, providing a more practical data foundation for the study of material performance mechanisms.

[0018] Furthermore, this invention integrates static and dynamic measurement functions within a single device platform, uniformly deploys B / J and H coil sensing arrays based on the closed magnetic circuit method in the hardware topology, and combines this with signal acquisition and processing circuits possessing high-frequency response capabilities. This achieves seamless switching across all operating conditions, from static magnetic property parameter measurement to high-frequency dynamic hysteresis characteristic testing. This integrated design avoids the positional deviations and stress disturbances introduced by repeated sample clamping during traditional multi-platform testing, ensuring the continuity and consistency of data between different testing stages, thereby significantly improving the accuracy and repeatability of magnetic property characterization results.

[0019] Meanwhile, by introducing high-precision sensing and detection and a multi-physics closed-loop control algorithm, this invention can maintain the stability of the electromagnetic, temperature, and stress states of the sample in real time during testing, effectively reducing the impact of environmental disturbances and system nonlinearities on the measurement results, thereby improving the reliability of testing under high-frequency dynamic and extreme conditions. Based on the multi-field coupled magnetic characteristic data obtained by this device, it can be directly used to construct high-precision material models and provide key parameter support for the electromagnetic design of permanent magnet motors, magnetic sensors, and related electrical equipment.

[0020] From an engineering application perspective, this invention can significantly reduce the reliance on experience margins in traditional design processes, reduce the risk of over-design or failure due to insufficient understanding of material properties, shorten the prototype development cycle, and reduce the selection and trial production costs of high-performance permanent magnet materials, thus possessing significant engineering promotion value and economic benefits. Furthermore, this technology plays a crucial supporting role in improving the precision design level and reliability of permanent magnet materials and related electrical equipment. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the present invention. Figure 1 .

[0022] Figure 2 This is a schematic diagram of the overall structure of the present invention. Figure 2 .

[0023] Figure 3 This is a three-dimensional structural schematic diagram of the mechanical stress loading mechanism of the present invention.

[0024] Figure 4 This is a three-dimensional structural diagram of the manual displacement platform of the present invention.

[0025] Figure 5 This is a three-dimensional structural diagram of the electric displacement platform of the present invention.

[0026] Figure 6 This is a three-dimensional structural schematic diagram of the auxiliary magnetic yoke displacement mechanism of the present invention.

[0027] Figure 7 This is a schematic diagram of the connection structure between the main magnetic yoke and the magnetic yoke pole head of the present invention.

[0028] Figure 8 This is a schematic diagram of the structure of the top plate surface of the present invention.

[0029] Figure 9 This is a three-dimensional structural diagram of the temperature control execution module of the present invention.

[0030] Figure 10 This is a three-dimensional structural schematic diagram of the aluminum nitride ceramic mold of the present invention.

[0031] Figure 11 This is a schematic diagram of the connection structure between the polyether ether ketone oil bath and the support guide groove assembly of the present invention.

[0032] Figure 12 This is a three-dimensional structural schematic diagram of the support guide groove assembly of the present invention.

[0033] Figure 13 This is a schematic diagram of the connection principle of the permanent magnet material magnetic property measurement system provided by the present invention.

[0034] In the diagram: 1. Base plate; 2. Top plate; 3. Mechanical stress loading mechanism; 4. Auxiliary yoke displacement mechanism; 5. Frame support column; 6. Main yoke; 7. Auxiliary yoke; 8. Excitation winding; 9. Temperature control actuator module; 10. Pole head fastener; 11. Magnetic yoke pole head; 12. Temperature control circulating oil tank; 13. Permanent magnet material magnetic property measuring device; 14. Winding matching terminal block; 15. Support guide slot assembly; 16. Mechanism fixing base; 17. Manual displacement platform; 18. Electric displacement platform ; 19. Main yoke connecting rod fixing block; 20. Connecting rod; 21. Pressure sensor connecting bracket; 22. Pressure sensor; 23. Main yoke fixing connector; 24. Main yoke manual displacement handwheel; 25. Displacement slider; 26. Manual slide base; 27. Manual transmission lead screw; 28. Mechanical deadlock positioning hole; 29. ​​Manual displacement guide rail; 30. Manual platform motor transmission conversion mechanism; 31. High torque servo drive motor; 32. Electric platform mechanical deadlock positioning hole; 33. Electric transmission lead screw; 34. ; 35. Electric slider; 36. Auxiliary yoke upper clamp; 37. Auxiliary yoke lower clamp; 38. Auxiliary yoke displacement connecting rod; 39. Auxiliary yoke connecting rod fixing block; 40. Auxiliary displacement slider; 41. Mechanical deadlock fastener; 42. Auxiliary platform base; 43. Auxiliary handwheel; 44. Auxiliary yoke platform fixing mechanism; 45. Pole head lower fastener; 46. Pole head fastener; 47. Pole head fastener; 48. Rectangular slot; 49. Displacement and wiring guide groove; 50. Polyetheretherketone oil bath; 51. Upper circulation quick-change connector; 52. 53. Lower circulation quick-change connector; 54. Aluminum nitride ceramic mold; 55. Test sample; 56. B / J sensor and its compensation coil placement slot; 57. Inner and outer thermistor mounting slots; 58. H coil mounting slot; 191. Oil drain port slot; 102. Downward extending guide slot; 152. Tee; 1521. Upper interface; 1522. Middle interface; 1523. Lower interface; 491. Guide rail slot a; 492. Winding wire slot; 493. Guide rail slot b; 494. Sensor wire slot; 901. Housing protrusion block. Detailed Implementation

[0035] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and preferred embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0036] In the description of the invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention.

[0037] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "setting," and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection, an indirect connection through an intermediate medium, or a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0038] Example 1: As shown in the figure, this invention provides a multi-physics field coupled permanent magnet material magnetic property measurement device 13, including a high-rigidity frame, a mechanical stress loading mechanism 3, an auxiliary magnetic yoke displacement mechanism 4, a temperature control execution module 9, and a sensing and monitoring system. The main body of the frame is made of SUS304 austenitic stainless steel, which effectively eliminates the interference and leakage current of structural components on the test magnetic field by utilizing its excellent magnetic neutrality characteristics, and ensures the structural rigidity under axial mechanical stress loading by relying on its high elastic modulus. In the high-rigidity frame, the base plate 1 and the top plate 2 are parallelly connected by four symmetrically arranged frame support columns 5. The vertical space formed between them is used to realize the physical isolation wiring of the excitation circuit and the sensing signal line, thereby optimizing the electromagnetic compatibility performance of the system. The two ends of the frame support columns 5 are rigidly fixed to the base plate 1 and the top plate 2 by M6 high-strength bolts and precision cylindrical positioning pins. This bolt pre-tightening and pin-limiting assembly method ensures that the overall verticality and planar parallelism of the frame do not drift during the application of axial high pressure stress, providing a stable geometric reference for the internal magnetic circuit system.

[0039] In the geometric layout of the top plate 2, parallel displacement and wiring guide grooves 49 are precisely machined along the axial direction in the middle of the top plate 2. The displacement and wiring guide grooves 49 include a guide rail groove located below the mechanical stress loading mechanism 3, a sensing wire groove 494 located below the auxiliary magnetic yoke displacement mechanism 4, and a winding wire groove 492. Among them, the guide rail grooves a491 and b493 serve as displacement guide grooves for moving parts, and the sensing wire groove 494 located on the geometric central axis is specifically used to lead out the sensing signal cable. Through this multi-groove parallel geometric misalignment design, and the interspersed winding wire grooves 492, physical spatial isolation between the high-voltage excitation power line and the low-voltage sensing signal line is achieved. The reason is that the excitation winding 8 carries a large current in the ampere range, while the sensor collects a sampling signal in the millivolt range. The two are prone to electromagnetic inductance. This layout increases the physical distance between the excitation line and the signal line. By using the electromagnetic field strength to decrease with distance and the material properties of the top plate 2 to isolate the electromagnetic inductance of the wires, the electromagnetic crosstalk of the alternating large current to the sampling circuit is suppressed, ensuring the reliability and repeatability of the measurement data under dynamic high-frequency conditions.

[0040] Two sets of mechanical stress loading mechanism 3 and auxiliary magnetic yoke displacement mechanism 4 are respectively provided and are arranged opposite each other on both sides of the top plate 2. The line connecting the two mechanical stress loading mechanisms 3 is perpendicular to the line connecting the two auxiliary magnetic yoke displacement mechanisms 4.

[0041] The mechanical stress loading mechanism 3 integrates the dual functions of precise movement of the magnetic yoke and mechanical stress loading. It is connected to a main magnetic yoke 6, and a magnetic pole head 11 is installed at the end of the main magnetic yoke 6. An excitation winding 8 is wound around the main magnetic yoke 6. The mechanical stress loading mechanism 3 is vertically mounted on both ends of the base plate 1 via a mechanism fixing base 16. The mechanical stress loading mechanism 3 includes a manual displacement platform 17, an electric displacement platform 18, and a main magnetic yoke fixed connector 23 connected to the electric displacement platform 18 via a connecting rod 20. The manual displacement platform 17 and the electric displacement platform 18 are assembled in series and stacked. The manual displacement platform 17 includes a manual slide base 26, a manual transmission screw 27, and a displacement slider 25. The manual slide base 26 is fixed on the lower layer and drives the displacement slider 25 to perform a large load release movement along the manual displacement guide rail 29 via the manual transmission screw 27. The electric displacement platform 18 is fixed above the displacement slider 25 and is driven by a high-torque servo drive motor 31 via a manual platform motor transmission conversion mechanism 30 and an electric transmission screw 33 to drive the electric slider 34 to perform precision feeding.

[0042] The connecting rod 20 is rigidly connected to the electric slider 34 via the main magnetic yoke connecting rod fixing block 19. The root of the main magnetic yoke 6 is precisely embedded in the pre-set tight-fit groove of the main magnetic yoke fixing connector 23. The main magnetic yoke fixing connector 23 is made of high-rigidity, high-temperature resistant cloth-based phenolic laminate or polyetheretherketone material. The magnetic yoke is firmly locked by non-magnetic bolts and side pressure strips. This embedded design utilizes the high compressive strength of the material to ensure that the axial thrust of the displacement platform can act on the magnetic yoke without damage during the stress loading stage. Specifically, in this example, the combination of high-performance composite materials and the embedded slot of the main magnetic yoke achieves mechanical rigidity isolation between the excitation circuit and the transmission system and the multi-physics field test environment. This ensures the linear transmission of axial stress between the magnetic yoke and the displacement platform, eliminates displacement deviation of the connecting parts under high stress loading conditions, plays a role in heat insulation, blocks the heat conduction from the oil bath temperature field to the rear transmission mechanism, reduces the difficulty of mechanical thermal expansion and contraction on displacement accuracy, stress application and control, cuts off the closed conductive path of the embedded magnetic yoke, eliminates circulating interference, and improves the comprehensive measurement accuracy under multi-field coupling environment.

[0043] A pressure sensor 22 is installed between the main magnetic yoke fixing connector 23 and the connecting rod 20. The back of the main magnetic yoke fixing connector 23 is rigidly coupled to one end of the pressure sensor 22 via a thread, while the other end of the pressure sensor 22 is connected to the connecting rod 20 via a pressure sensor connecting bracket 21. Geometrically, the connecting rod 20, the sensor, and the central axis of the main magnetic yoke 6 are strictly coincident, ensuring the coaxiality of stress loading and avoiding measurement errors caused by off-center loading. Physically, the non-metallic main magnetic yoke fixing connector 23 constructs a physical isolation layer between the magnetic yoke 6 (heat source / magnetic source) and the displacement platform, preventing the transmission of high-temperature oil bath heat to the servo drive system and cutting off possible eddy current circulation paths, thus ensuring the operating accuracy of the displacement mechanism and the intrinsic nature of the test data.

[0044] The auxiliary yoke displacement mechanism 4 is connected to the auxiliary yoke 7, forming a closed magnetic loop through the docking of the main yoke 6 and the auxiliary yoke 7. The auxiliary yoke displacement mechanism 4 serves as a positional compensation reference for constructing the closed magnetic circuit and is rigidly mounted to the far end of the base plate 1 via the auxiliary yoke platform fixing mechanism 45. The auxiliary yoke displacement mechanism 4 includes an auxiliary platform base 41 and an auxiliary displacement slider 39 mounted thereon. The slider is driven to precisely reciprocate axially by rotating the auxiliary handwheel 42. The auxiliary yoke 7 is limited by a confining structure consisting of an upper auxiliary yoke clamp 35 and a lower auxiliary yoke clamp 36, and is connected to the auxiliary displacement slider 39 via two symmetrically arranged auxiliary yoke displacement connecting rods 37. The connecting rods are cantilevered and supported by the auxiliary yoke connecting rod fixing block 38, ensuring the coincidence of the end face of the auxiliary yoke 7 with the axis of the main yoke 6. To ensure the static characteristics of the magnetic circuit during testing, the slide table is equipped with a mechanical locking fastener 40 on its side. After the auxiliary magnetic yoke 7 is precisely fitted with the end face of the sample, the displacement gap is eliminated by physical locking. It is made of SUS304 stainless steel and hard aluminum alloy to balance mechanical rigidity and non-magnetic environment requirements. In actual use, the relative displacement of the auxiliary magnetic yoke 7 is predetermined according to the geometric parameters of the experimental design. Before measurement, the auxiliary magnetic yoke 7 is driven by a manual precision slide table towards the core testing area until it achieves precise fit with the end face of the main magnetic yoke 6. Subsequently, the mechanical locking mechanism equipped on the manual slide table rigidly fixes the auxiliary magnetic yoke 7 in its current position, thereby providing a stable closed magnetic circuit for measurement.

[0045] In terms of magnetic circuit construction and excitation system, a closed magnetic loop is formed by the docking of the main yoke 6 and the auxiliary yoke 7. The main yoke 6 uses a high-saturation magnetic induction intensity and low-loss oriented silicon steel laminated core to ensure that the excitation intensity is sufficient to cover the testing requirements of a full range of permanent magnet materials, from low-coercivity ferrites to high-coercivity NdFeB. The auxiliary yoke 7 uses a low-loss non-oriented silicon steel laminated core and presents a semi-circular ring configuration. Its junction with the main yoke 6 adopts an inward curvature design optimized by finite element simulation, which aims to guide the magnetic field lines to close smoothly by compensating for interface magnetic reluctance, effectively suppressing edge leakage magnetics, and constructing a closed magnetic circuit that meets the requirements. This magnetic circuit configuration significantly improves the spatial distribution stability and gain efficiency of the excitation field, ensuring that when measuring high-coercivity samples, the nonlinear distortion of the magnetic field waveform is reduced as much as possible, and the leakage magnetic interference is reduced to a low level.

[0046] The excitation winding 8 is made of multiple strands of low-loss Litz wire wound on the yoke and led out through the winding matching terminal 14. Depending on the measurement requirements, the winding can be switched between series connection (increasing inductive reactance to match the high-voltage DC source) or parallel connection (increasing current carrying capacity to match the high-current power amplifier), enabling the device to adapt to different test material sample requirements and improving the utilization efficiency of the power source. Furthermore, the winding adopts a segmented, split layout, utilizing microscale heat dissipation channels reserved between layers and a physical thermal barrier formed by multiple layers of F-class DMD insulation material. This not only enhances the convective heat dissipation efficiency inside the winding but also effectively suppresses the interference of excitation source temperature rise on the intrinsic characteristics of the magnetic circuit, thereby ensuring the electrical safety and measurement accuracy consistency of the measurement system under high-power continuous operation. To address the saturation magnetization requirements of ultra-high coercivity permanent magnet materials and to cope with the thermal shock risk caused by extremely high current density, the excitation winding 8 in this example can adopt an active cooling architecture. For example, the excitation conductor can be replaced with a hollow copper conductor with built-in microchannels, and forced convection cooling can be achieved through an external circulating cooling water system; or a non-magnetic heat-conducting jacket can be added to the outer layer of the winding, and the Joule heat generated during the excitation process can be carried away by circulating high specific heat capacity liquid. Without changing the main topology of the magnetic circuit, the device's adaptability to testing samples with extremely high coercivity is greatly expanded.

[0047] The magnetic yoke pole head 11 serves as the excitation core and is detachably connected to the magnetic yoke end face via the slot embedding method of the pole head fasteners 10 (lower pole head fastener 46 and upper pole head fastener 47). For irregularly shaped samples, a customized pole head with the same curvature as the sample can be replaced (it can be flexibly replaced with rectangular, tile-shaped, or cylindrical geometric forms according to the sample topology) to ensure full contact between the pole head end face and the sample 54 under test. This eliminates problems such as local magnetic saturation, excessive air gap magnetic reluctance, and magnetic field distribution distortion caused by "point / line contact," ensuring the authenticity of the measurement of the intrinsic magnetic parameters inside complex-shaped samples.

[0048] The temperature control execution module 9 adopts a heat transfer architecture based on liquid-solid coupling, including a polyetheretherketone (PEEK) oil bath 50 and an aluminum nitride ceramic mold 53 located in the middle of the PEEK oil bath 50. The PEEK oil bath 50 is connected to a temperature-controlled circulating oil storage tank 12. In this example, a rectangular slot 48 is opened in the middle of the top plate 2, and a support guide groove assembly 15 is arranged below the rectangular slot 48. The PEEK oil bath 50 is inserted into the support guide groove assembly 15. Specifically, the outer wall of the PEEK oil bath 50 is machined with vertically distributed box protrusions 901, and the inner wall of the support guide groove assembly 15 is precision machined with downwardly extending guide grooves 151. The two are fitted together to form a vertical insertion self-centering mechanism. During assembly, the housing descends vertically along the guide groove 151 via the protruding block 901 to achieve limiting and high-precision centering. This design solves the problem of blind insertion caused by the narrow opening of the top plate 2 while ensuring quick assembly and disassembly, enhances the stability of the system during testing, and ensures that the center of the sample is always at the geometric center of the magnetic field.

[0049] In terms of oil circuit construction, the upper circulation quick-change connector 51 and the lower circulation quick-change connector 52 are respectively connected to the external temperature-controlled circulation oil tank 12 through high-strength heat-resistant corrugated pipes, forming a closed-loop oil heat exchange circulation. The heat transfer oil enters from the bottom and overflows from the top, forming a forced convection circulation of "bottom in and top out". The lift force is used to vent the air residue in the tank, preventing cavitation from creating thermal dead zones, and realizing real-time precise control and temperature stability of the thermal field in the core test area.

[0050] An oil drain interface groove 58 is provided on the support guide groove assembly 15. A tee 152 is provided in the oil drain interface groove 58. The upper interface 1521 of the tee 152 is directly connected to the bottom of the polyether ether ketone oil bath 50 through a lower circulation quick-connect connector 52. The middle interface 1522 of the tee 152 is connected to the external temperature-controlled circulation oil storage tank 12. The lower interface 1523 of the tee 152 is connected to the horizontally led-out oil drain pipe through an L-shaped adapter. When the system performs a test cycle, the valve at the far end of the oil drain pipe is closed, so that the lower interface 1523 and its connected L-shaped branch are in static pressure balance. At this time, the lower interface 1523 branch plays the role of "pressure stabilization and slag collection" and ensures that the heat transfer oil enters from the middle interface 1522 and is stably supplied to the core area of ​​the sample through the upper interface 1521. When forced release is required after the test, the remote valve is opened, and the oil is discharged smoothly from the lowest physical position lower interface 1523 through the L-shaped adapter under the drive of gravitational potential energy, achieving efficient oil discharge in a compact space.

[0051] The aluminum nitride ceramic mold 53 serves as the sample carrier, supporting the test sample 54. Utilizing its high thermal conductivity, it rapidly and uniformly transfers the oil bath temperature rise to the test sample 54. This physical configuration, leveraging oil convection and the high thermal conductivity of ceramics, ensures that the internal and external temperature difference of the sample is controlled within a minimal range during the Curie temperature rise process, guaranteeing the accuracy of thermal characteristic measurements. Specifically, in this example, the aluminum nitride ceramic mold 53 is positioned and installed at the center of the chamber via a stepped groove. Utilizing its combination of high thermal conductivity and extremely high dielectric strength, it achieves rapid and stable heat transfer from the oil bath environment to the permanent magnet test sample 54, significantly shortening the system's thermal equilibrium time. The technical advantages of this design are as follows: First, the non-conductive properties of aluminum nitride ceramic material completely eliminate the eddy current shielding effect caused by electromagnetic induction in metal heat conductors under dynamic magnetic testing, ensuring that the magnetic flux detection signal is not interfered with; second, the non-metallic components create a pure electromagnetic measurement environment, eliminating the nonlinear distortion of the material's magnetic properties caused by temperature fluctuations; finally, by utilizing the high compressive stiffness of the ceramic mold, it can ensure that the sample does not shift position or deform geometrically under high temperature conditions when performing axial stress loading, thus guaranteeing the physical boundary stability of the "temperature-force-magnetic" multi-field coupling test.

[0052] The sensing and monitoring system includes: two sets of concentric circular coils, one main and one auxiliary, which are connected in series and reversed to achieve differential compensation and real-time cancellation of the air magnetic flux component between the sensor and the sample; an H-coil, which obtains the magnetic field strength inside the sample based on the principle of tangential magnetic field continuity; and a thermistor, which calculates the radial thermal resistance of the aluminum nitride ceramic mold 53 through dual-point monitoring to verify the temperature field uniformity and provide measured temperature difference compensation for the Smith pre-estimation method. The sensing and monitoring system is integrated into a precision pre-set groove inside the aluminum nitride ceramic mold 53, ensuring the geometric consistency between the detection point and the physical field source. The B / J sensor and its compensation coil placement groove 55 contains the two sets of concentric circular coils, and the H-coil mounting groove 57 is opened on the inner side wall of the mold, ensuring that the plane of the H-coil is strictly parallel to the side of the sample. Temperature monitoring adopts a hierarchical architecture, with thermistors (Pt100 sensors) placed in the inner and outer thermistor mounting grooves 56 respectively. The outer sensor captures the temperature of the oil bath medium in real time, while the inner sensor senses the temperature near the sample wall, thus achieving dual-point differential monitoring.

[0053] Example 2: This application also discloses a multi-physics field coupled permanent magnet material magnetic property measurement system, including the above-mentioned multi-physics field coupled permanent magnet material magnetic property measurement device and an integrated measurement circuit. The integrated measurement circuit includes an industrial computer, an NI data acquisition card, a bipolar programmable high-power DC source, a wideband high-power amplifier, a circuit protection system, a reactive power compensation capacitive reactance matching group, a B / J signal differential processing circuit, an H signal differential processing circuit, a gaussmeter, a displacement control system, a mechanical stress control system, and a temperature control system.

[0054] The measurement system and control circuit disclosed in this application integrate high-precision signal conditioning, high-power excitation drive, and multi-field closed-loop control logic. Its core topology consists of an industrial computer 59 and an NI data acquisition card 60 integrated on its internal bus. In the signal processing link, a sensor array located inside the ceramic mold leads the weak potential signal induced to the B / J signal differential processing circuit 65 and the H signal differential processing circuit 66. The differential circuit suppresses ambient electromagnetic noise through an operational amplifier with a high common-mode rejection ratio, and the pre-processed analog voltage signal enters the NI data acquisition card 60 for high-frequency synchronous sampling. For static calibration of conventional samples, a gaussmeter 67 directly transmits the detected value to the LabVIEW measurement and control platform of the industrial computer 59 via a communication interface (RS232).

[0055] During static testing, the bipolar programmable high-power DC power source 61 supplies power to the excitation winding through the winding matching terminal 14. At this time, the industrial computer 59 reads the current sampling data inside the DC power source in real time through the communication interface and compares it with the preset magnetization step target value. Using a software PID algorithm, the system dynamically adjusts the output voltage / current command of the DC power source to compensate for impedance temperature drift caused by winding heating, ensuring that the steady-state error of the excitation current is minimized at each quasi-static test point, thereby guaranteeing the measurement accuracy of the demagnetization curve (JH curve) or hysteresis curve (BH curve).

[0056] During dynamic testing, the analog output of the NI data acquisition card 60 acts as a high-precision signal generator, providing an excitation reference waveform for the wideband high-power power amplifier 62. To address the nonlinear effects of inductive load variations with frequency under dynamic conditions, the system incorporates real-time waveform feedback compensation logic (waveform pre-distortion control): the NI data acquisition card 60 synchronously monitors the actual excitation current waveform in the power circuit and calculates its deviation from the standard waveform. The industrial computer 59 uses iterative learning control or feedforward compensation algorithms to perform real-time pre-distortion correction on the reference signal at the analog output, offsetting the nonlinear distortion of the power amplifier and the effects of residual inductive reactance in the circuit. This feedback mechanism ensures that the excitation magnetic field waveform applied to the sample remains highly symmetrical and linear, effectively eliminating loss calculation errors caused by current distortion.

[0057] A reactive power compensation capacitive reactance matching component 64 is connected in series in the power circuit. Impedance matching is achieved by adjusting the capacitor capacity to compensate for the inductive reactance generated by the excitation winding at high frequencies, ensuring that the current waveform is not distorted. The entire power circuit is integrated with a circuit protection system 63 at the beginning. This system monitors the circuit status through a fast electronic switch. When a short circuit, overcurrent, or occasional power failure is detected, it forces a switch to the energy dissipation path to prevent the back electromotive force of the inductive load from breaking down the system insulation.

[0058] The displacement control system 68 controls the axial motion of the main magnetic yoke displacement and the mechanical stress loading mechanism 3 in a graded manner. During the sample feeding stage, the system operates primarily in electric mode, with the displacement control system 68 driving a high-torque servo drive motor 31 via an electric transmission screw 33 to perform precise feeding, achieving controlled approach between the pole head and the sample. During this process, the system monitors the dynamic torque current of the motor at high frequency, determining load changes in real time to prevent rigid collisions between the pole head and the sample. In the retraction stage after the test, to address the significant magnetic attraction force generated by the highly remanent magnetic sample, when the drive motor detects that the output torque is approaching a threshold or there is a risk of stalling, the operator activates the main magnetic yoke manual displacement platform 17 via the main magnetic yoke manual displacement handwheel 24. The extremely high mechanical gain of the manual transmission screw 27 generates a powerful disengagement displacement, which, in conjunction with the manual platform motor transmission conversion mechanism 30, forcibly overcomes the magnetic attraction force. Once the pole head and sample are completely disengaged and the attraction force has decreased to a safe range, the electric mode is restored to perform a full-stroke retraction, thus ensuring that the mechanical transmission chain is not damaged by instantaneous overload and guaranteeing the absolute safety of equipment operation.

[0059] The mechanical stress control system 69 achieves precise closed-loop control of the axial load on the permanent magnet test sample 54 based on real-time feedback from the pressure sensor 22. During the initial clamping stage, the system controls the electric displacement platform to perform micro-step feeding, simultaneously acquiring the feedback signal from the pressure sensor 22. When the pressure value shows a linear increase that meets a preset threshold, the system automatically determines that the end face of the pole head has achieved physical contact with the sample surface, and uses this as the geometric reference point for zero-stress testing. After entering the formal loading process, the system switches to a constant-pressure closed-loop mode, using an improved PID algorithm to dynamically fine-tune the incremental displacement of the servo motor to compensate for contact stress fluctuations caused by sample geometric tolerances or thermal expansion and contraction. By continuously adjusting the advance amount of the connecting rod 20, the system can control the steady-state error of the preset pressure value within a very small range. After loading is completed, the mechanical dead-locking positioning hole 28 and the electric platform mechanical dead-locking positioning hole 32 are used to assist in locking the mechanical posture, maintaining the stability of stress throughout the measurement process, thereby reducing the magnetic characteristic measurement deviation caused by stress relaxation.

[0060] The temperature control system 70 is responsible for the overall thermal field management of the temperature-controlled circulating oil tank 12 and the polyetheretherketone (PEEK) oil bath tank 50. The system retrieves signals from Pt100 sensors embedded in the mounting slots 56 of two sets of thermistors on the inner and outer sides of the aluminum nitride ceramic mold 53 in real time, constructing a dual-loop temperature feedback network. Addressing the significant hysteresis and time-varying physical characteristics in the oil bath heat transfer process, the control algorithm employs a Smith predictor compensation combined with a fuzzy PID strategy. It pre-calculates the heat conduction delay time using a mathematical model and introduces a feedforward compensation term, performing pre-adjustment before feedback deviations occur, effectively eliminating temperature overshoot and fluctuations near the Curie temperature point. For liquid circulation heating, the system drives the heat transfer oil to circulate between the upper / lower circulation quick-connect joints 51 and 52 in a "bottom in, top out" manner, utilizing the pressure difference to completely vent air bubbles in the tank, and dynamically adjusting the circulation pump speed according to the real-time temperature difference. This closed-loop mechanism ensures that the core and surface of the sample are in a highly consistent thermal field environment, fundamentally preventing unexpected demagnetization of the material due to excessive local temperature rise, and ensuring the accuracy and repeatability of thermomagnetic evolution law measurement.

[0061] In this embodiment, an industrial computer 59 collaboratively processes the feedback data from the three subsystems mentioned above, ensuring that the displacement deviation, surface pressure, and core temperature of the sample are within a preset convergence range during each set of magnetic property data sampling. All acquired B, H, and J signals are digitally integrated and compensated in real time by a LabVIEW program, ultimately plotting the static and dynamic magnetic property curves under different stresses and temperatures, as well as the intrinsic properties of the material.

[0062] Example 3: Based on the above examples, the working principle and process of the measurement system provided in this application are as follows: Step S1: Sensor mold preparation and sample initialization clamping Place the permanent magnet test sample into the sample slot at the center of the aluminum nitride ceramic mold. Ensure that the B / J sensor and its compensation coil are evenly wound in the groove on the inner wall of the mold, maintaining the orthogonal geometric relationship between the coil and the sample surface. Then, connect the H coil and the inner and outer thermistors to the corresponding mounting slots, and slide the entire mold into the center of the polyetheretherketone (PEEK) oil bath using the oil bath support guide assembly. Finally, push the entire oil bath into the test position. If studying the electromagnetic-thermal characteristics of the sample, ensure that the upper / lower circulation quick-connect connector is connected to the external circulation loop, and test the circulation and oil circuit sealing. After confirming the test is successful, proceed to the next step.

[0063] Step S2: Axial alignment, zero-stress reference calibration and magnetic circuit closure The displacement control system is activated, driving the main yoke electric platform to control the pole head to perform axial probing feed at low speed. Simultaneously, the mechanical stress control system is activated to monitor the feedback signal from the pressure sensor in real time; when the pressure value shows a linear increase that meets a preset threshold, it is determined that the pole head and the sample have achieved physical contact, and the current coordinates are recorded as the "zero-stress reference point." Subsequently, the auxiliary handwheel is rotated to adjust the auxiliary yoke displacement mechanism, ensuring a tight fit between the auxiliary yoke and the side of the main yoke, and rigid locking is achieved using a mechanical deadlock fastener, constructing a complete low-resistivity closed magnetic circuit.

[0064] Step S3: System wiring and power loop impedance matching The circuit is switched according to the experimental conditions (static or dynamic). During static testing, the excitation winding is connected to a bipolar programmable high-power DC source; during dynamic testing, it is connected to a wideband high-power amplifier, and the capacity of the reactive power compensation capacitive reactance matching group is adjusted according to the test frequency to offset the winding inductive reactance and achieve impedance matching. At the same time, the outputs of the B / J signal differential processing circuit and the H signal differential processing circuit (a gaussmeter can be used in static cases) are connected to the NI data acquisition card to form a signal acquisition feedback closed loop.

[0065] Step S4: Automated adjustment and steady-state determination of multiphysics coupled operating conditions Each control subsystem is adjusted according to preset conditions to execute specific coupled operating conditions. If an electromagnetic-thermal-mechanical operating condition is executed, the temperature control system drives the heat transfer oil circulation through the Smith pre-estimation method until the near-wall temperature of the sample stabilizes; at the same time, the mechanical stress control system drives the motor to apply a preset axial load to ensure that the sample is in a simulated service environment of constant temperature and pressure during the measurement transient.

[0066] Step S5: Magnetic characteristic signal acquisition, waveform feedback and data storage After adjusting the LabVIEW program parameters within the industrial computer, the system begins outputting excitation commands. During static testing, the industrial computer reads the current sampling data from the DC source in real time via the communication interface and compares it with the preset magnetization step target value. The system dynamically adjusts the output voltage / current of the DC source. During dynamic testing, the program uses the NI data acquisition card to feedback control the power source, causing the excitation voltage amplitude to increase in a stepwise or sinusoidal manner. The system monitors the induced waveforms of magnetic flux density B, magnetic field strength H, and magnetic polarization J in real time. If the dynamic waveform is distorted, the system executes a feedback compensation algorithm to correct the output until the sample reaches magnetic saturation. During this process, LabVIEW automatically stores the magnetic characteristic data package for each operating condition.

[0067] Step S6: Safe demagnetization and field energy release After the required feature point data is collected, the system enters the demagnetization logic. For static testing, the current is decreased alternately by alternating positive and negative values; for dynamic testing, the amplitude of the high-frequency excitation signal is gradually reduced. Subsequently, the circuit protection system performs a physical shutdown, using the internal short-circuit dissipation path to absorb the back electromotive force released by the inductive load under high field, preventing voltage transients from breaking down the system insulation and ensuring that the equipment is in a safe zero position.

[0068] Step S7: Iteration and Loss Model Analysis under Multi-Field Coupled Operating Conditions Repeat steps four through six, changing the temperature (via a temperature control system), pressure (via a mechanical stress control system), or excitation frequency according to a preset gradient. The system automatically plots and records the trajectories of magnetic induction and magnetic field strength under different coupling environments and different excitation currents. Using the stored complete dataset, combined with a loss decomposition model, the system calculates the iron loss and energy density changes of the sample under specific working conditions, and then analyzes the electromagnetic-thermal-mechanical evolution of the material.

[0069] Step S8: Mechanical forced separation and sample repositioning and retrieval After the entire measurement process is completed, the high-torque servo drive motor is activated to perform a rapid retraction stroke, freeing up storage space. If the large magnetic attraction force generated by the highly remanent magnetized sample prevents the motor from driving it out, first rotate the main magnetic yoke manual displacement handwheel to activate the manual platform. Utilize the high mechanical gain of the lead screw to forcibly generate an initial disengagement displacement until the magnetic attraction force weakens. After draining the oil through the bottom drain port, the sample is removed, completing the testing task.

[0070] The above description is only a preferred embodiment of 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 principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A device for measuring the magnetic properties of permanent magnet materials using multi-physics coupling, characterized in that, The system includes a top plate, a temperature control execution module located in the middle of the top plate, a sensing and monitoring system located in the middle of the temperature control execution module, two sets of mechanical stress loading mechanisms positioned opposite each other on both sides of the top plate, and two sets of auxiliary magnetic yoke displacement mechanisms. The line connecting the two mechanical stress loading mechanisms is perpendicular to the line connecting the two auxiliary magnetic yoke displacement mechanisms. The mechanical stress loading mechanism is connected to a main magnetic yoke, and magnetic pole heads are installed at the ends of the main magnetic yoke. An excitation winding is wound around the outside of the main magnetic yoke. The auxiliary magnetic yoke displacement mechanism is connected to an auxiliary magnetic yoke, and a closed magnetic loop is formed by the docking of the main magnetic yoke and the auxiliary magnetic yoke.

2. The multi-physics field coupled permanent magnet material magnetic property measurement device according to claim 1, characterized in that, The mechanical stress loading mechanism includes a manual displacement platform, an electric displacement platform, and a main magnetic yoke fixed connector connected to the electric displacement platform via a connecting rod. The manual displacement platform and the electric displacement platform are assembled in series and stacked, and a pressure sensor is installed between the main magnetic yoke fixed connector and the connecting rod.

3. The multi-physics coupled permanent magnet material magnetic property measurement device according to claim 2, characterized in that, The root of the main magnetic yoke is precisely embedded in the pre-set tight-fit groove of the main magnetic yoke fixing connector.

4. The multi-physics field coupled permanent magnet material magnetic property measurement device according to claim 2 or 3, characterized in that, The magnetic yoke pole head is detachably connected to the end face of the magnetic yoke through a slotted insertion method between the lower fastener and the upper fastener.

5. The multi-physics field coupled permanent magnet material magnetic property measurement device according to claim 1, characterized in that, The temperature control execution module includes a polyetheretherketone (PEEK) oil bath and an aluminum nitride ceramic mold located in the middle of the PEEK oil bath. The PEEK oil bath is connected to a temperature-controlled circulating oil storage tank.

6. The multi-physics field coupled permanent magnet material magnetic property measurement device according to claim 5, characterized in that, A rectangular slot is provided in the middle of the top plate, and a support guide groove assembly is provided below the rectangular slot. The polyether ether ketone oil bath is inserted into the support guide groove assembly.

7. The multi-physics coupled permanent magnet material magnetic property measurement device according to claim 6, characterized in that, The polyetheretherketone oil bath is connected to the temperature-controlled circulating oil tank on its upper and lower sides via an upper circulation quick-change connector and a lower circulation quick-change connector, respectively. The support guide groove assembly is provided with an oil drain interface groove, and a tee is provided in the oil drain interface groove. The upper interface of the tee is directly connected to the bottom of the polyether ether ketone oil bath tank through a lower circulation quick-connect fitting. The middle interface of the tee is connected to an external temperature-controlled circulation oil storage tank. The lower interface of the tee is connected to a horizontally led-out oil drain pipe through an L-shaped adapter.

8. The multi-physics coupled permanent magnet material magnetic property measurement device according to any one of claims 5-7, characterized in that, The aluminum nitride ceramic mold is used to support the sample being tested, and the sensing and monitoring system is integrated within the aluminum nitride ceramic mold. The sensing and monitoring system includes: Two sets of concentric circular coils, main and auxiliary, are connected in series and reversed to achieve differential compensation and real-time cancellation of the air magnetic flux component between the sensor and the sample; H-coil, based on the principle of tangential magnetic field continuity, to obtain the internal magnetic field strength of the sample; The thermistor is designed to calculate the radial thermal resistance of the aluminum nitride ceramic mold through dual-point monitoring to verify the uniformity of the temperature field and to provide measured temperature difference compensation for the Smith prediction method.

9. The multi-physics field coupled permanent magnet material magnetic property measurement device according to claim 1, characterized in that, The surface of the top plate is provided with multiple sets of displacement and wiring guide grooves. The displacement and routing guide grooves include a guide rail groove located below the mechanical stress loading mechanism, a sensing wire groove located below the auxiliary magnetic yoke displacement mechanism, and a winding wire groove, forming a physical spatial isolation between the strong electric excitation power line and the weak electric sensing signal line.

10. A multi-physics coupled permanent magnet material magnetic property measurement system, characterized in that, Includes the multi-physics field coupled permanent magnet material magnetic property measurement device and integrated measurement circuit as described in claim 1. The integrated measurement circuit includes an industrial computer, an NI data acquisition card, a bipolar programmable high-power DC source, a wideband high-power amplifier, a circuit protection system, a reactive power compensation capacitive reactance matching group, a B / J signal differential processing circuit, an H signal differential processing circuit, a gaussmeter, a displacement control system, a mechanical stress control system, and a temperature control system.

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