Amorphous alloy iron core loss and magnetization characteristic stress sensitivity test method

Abstract

The invention discloses a stress sensitivity test method for amorphous alloy iron core loss and magnetization characteristics, which comprises the following steps: S1, calculating stress distribution in a circular iron core sample, and selecting nine interference magnitude combinations to obtain the sizes of the outer diameter and the inner diameter of the iron core sample; s2, processing the iron-based amorphous alloy strip according to the same process sequence to obtain ten laminated iron core samples; s3, testing the size and quality of each iron core sample; s4, matching and grinding the outer diameters of the nine inner rings and the inner diameters of the nine outer rings with the nine iron core samples, and chamfering; s5, the nine upper pressing rings and the nine lower pressing rings are subjected to precise match grinding; s6, carrying out hot jacket installation on the nine iron core samples; s7, winding a primary winding and a secondary winding on each iron core sample; and S8, carrying out loss and magnetization characteristic test on all the iron core samples by using a soft magnetic material magnetic performance test system. According to the method, data support is provided for improving the accuracy of optimization design and performance analysis of the amorphous alloy high-speed motor.

Description

Technical Field

[0001] The present invention relates to the technical field of soft magnetic material testing, and in particular to a stress sensitivity testing method for loss and magnetization characteristics of an amorphous alloy core. Background Art

[0002] Today, energy shortages and environmental pollution have become major constraints hindering the sustainable development of my country's economy and society. Vigorously developing clean energy and prioritizing energy conservation and emission reduction in power equipment are key means of resolving this contradiction. As one of the most important power equipment, electric motors are used in virtually every sector of the national economy. my country's installed electric motor capacity exceeds 400 million kW, consuming over 60% of total electricity consumption, making them a significant energy consumer. The efficiency of electric motors in my country is 2-3 percentage points lower than that of developed countries. A 2 percentage point increase in efficiency could save approximately 100 billion kilowatt-hours of electricity annually, nearly equivalent to the annual power generation of the Three Gorges Dam hydropower station. This demonstrates the enormous potential for energy savings from improved motor energy efficiency.

[0003] With the advancement of intelligent industrial manufacturing technology, the development of motors towards higher efficiency, higher speed, and higher frequency is an inevitable future trend. High-frequency motors, with their advantages of small size, high power density, direct load drive capability, and high overall efficiency, are urgently needed in high-tech industries such as CNC machine tools and robotics, electric vehicles, wastewater treatment, flywheel energy storage, micro gas turbine power generation, high-speed centrifuges, high-speed air compressors, and defense. However, the technical difficulty of reducing energy consumption and the heat dissipation challenges associated with their small size have become a major constraint on their development. The AC loss (i.e., iron loss) of a motor's soft magnetic core accounts for approximately 40% of the motor's total losses. As motor speed and frequency continue to increase, the proportion of iron loss increases rapidly, making core loss a key factor affecting the efficiency of high-frequency motors. Currently, non-oriented silicon steel is the most widely used soft magnetic material for motor cores. Its advantage lies in its high saturation magnetic induction (1.8-2.1T), but its high coercivity and conductivity result in significant core losses. As the frequency increases, the AC loss of the silicon steel core will increase dramatically, which may cause overheating or even burning of the motor during high-frequency / high-speed operation.

[0004] Iron-based amorphous alloys are soft magnetic materials with long-range atomic disorder and short-range order. They combine high magnetic permeability with low losses. Their coercivity is approximately 5 A / m, compared to around 30 A / m for conventional silicon steel. Consequently, the hysteresis losses of iron-based amorphous alloys are much lower than those of silicon steel. Furthermore, the thickness of iron-based amorphous alloy strips is only about 25-30 microns, and their resistivity is about three times that of conventional silicon steel, resulting in eddy current losses far lower than those of silicon steel sheets. Consequently, the iron loss of iron-based amorphous alloys at power frequency is approximately 15% of that of conventional silicon steel, and at high frequencies, it is only 10% or even 5%. They are considered one of the soft magnetic materials with the best overall performance. Studies have shown that when iron-based amorphous alloys are used as replacements for non-oriented silicon steel in the stator core of high-frequency motors, iron loss can be reduced by 80-90% at frequencies above 500 Hz, increasing the motor's power density by approximately 40%. The use of iron-based amorphous alloy strips to prepare motor stator cores will break through the technical bottleneck of low efficiency of traditional high-speed motors caused by excessive high-frequency losses in silicon steel cores, and is expected to bring about upgrades to high-frequency / high-speed motors.

[0005] Although iron-based amorphous alloys have the advantages of low loss and high magnetic permeability, their loss and magnetization characteristics are sensitive to stress. That is, as the internal stress changes, the loss and magnetization characteristics of the amorphous alloy core will be greatly affected.

[0006] The cross-coupling of multiple physical fields, including electromagnetic fields, temperature fields, fluid fields, and stress fields, exists in motors. The amorphous alloy stator core is inevitably subjected to stress during machining, motor assembly, and operation, which affects the stator core's magnetic properties and loss characteristics. The stresses to which the amorphous alloy stator core is subjected include machining stress, assembly stress, electromagnetic stress, and thermal stress caused by changes in motor temperature rise. During motor assembly and actual operation, the stator core is primarily subject to thermal stress, radial stress, and a small amount of tangential stress when transmitting electromagnetic torque. For example, experimental studies have shown that when there is a 0.1mm interference fit between the amorphous alloy stator core and the motor housing, the stator core loss increases by approximately two times. Therefore, quantitatively studying the impact of stress on the loss and magnetization characteristics of the amorphous alloy core is essential for improving the accuracy of the optimized design and performance analysis of amorphous alloy high-speed motors.

[0007] Currently, there are a few qualitative studies on the effects of stress on the loss characteristics of amorphous alloy cores. For example, in the literature mentioned above, when there is interference with the motor housing, the loss of amorphous alloy cores increases by about two times. The researchers adjusted the interference by adjusting the gap size in the aluminum housing wall to measure the change in the loss of the motor stator core. However, this was only a qualitative test of the change in the overall loss of the motor core with the interference, without further research on the stress distribution and loss of a specific part of the stator core. Therefore, it is impossible to quantitatively determine the relationship between stress and core loss.

[0008] By applying uniform axial stress to laminated amorphous alloy core samples, it was found that the unit core loss of the stator core increased by about 20% with the increase of axial stress.

[0009] Furthermore, finite element calculations using bidirectional magnetic-thermo-solid coupling revealed that when the motor housing and the stator core have different interference fits, the stress in the stator core yoke increases from the outside in, particularly at the junction of the stator slot bottom and the stator tooth root, where the stress reaches its maximum value. Further research revealed that even for standard annular core specimens, when there is interference fit with the housing, the stress within the annular core is not uniformly distributed, but rather increases radially from the outside inward. As the interference fit increases, the overall stress within the annular core also increases, and the unevenness of the stress distribution becomes increasingly pronounced. Therefore, it is difficult to achieve uniform stress distribution within an annular core specimen simply by adjusting the interference fit with the stator housing, and there is no way to quantitatively test the loss and magnetization characteristics of amorphous cores under uniformly distributed stress conditions.

[0010] Standardized testing of the loss and magnetization characteristics of amorphous alloy core specimens under uniformly distributed radial stress is a prerequisite for quantitatively studying the effects of stress on these characteristics, thereby fully leveraging the advantages of amorphous alloys in terms of low high-frequency losses. This is also a prerequisite for improving the accuracy of optimized design and performance analysis of amorphous alloy high-speed motors. Currently, no research has examined the loss and magnetization characteristics of amorphous alloy core specimens under uniformly distributed stress. Summary of the Invention

[0011] The purpose of the present invention is to provide a stress sensitivity testing method for loss and magnetization characteristics of an amorphous alloy core, so as to solve the problems mentioned in the background technology.

[0012] To achieve the above objectives, the present invention provides a stress sensitivity testing method for loss and magnetization characteristics of an amorphous alloy core, comprising the following steps:

[0013] S1. Use the finite element method to calculate the stress distribution inside annular iron core specimens of different main dimensions and under different interference combinations of the inner and outer rings. Select nine sets of interference combinations corresponding to different stresses that are approximately uniformly distributed inside the iron core specimens with the same main dimensions. At the same time, obtain the outer and inner diameter dimensions of the iron core specimens when the stress is approximately uniformly distributed. The iron core specimens are amorphous alloy specimens, the inner and outer rings are both made of titanium alloy, and the upper and lower pressure rings are made of non-magnetic stainless steel.

[0014] S2. Select an iron-based amorphous alloy strip having a width greater than the outer diameter of the iron core sample when the stress is approximately uniformly distributed in step S1, and process the iron-based amorphous alloy strip at one time according to the same process sequence to obtain ten annular iron core samples having the same main dimensions as in step S1;

[0015] S3. Use high-precision inside micrometer, high-precision outside micrometer and balance to test each core sample;

[0016] S4. According to the interference combinations of the outer and inner rings calculated in step S1, and based on the inner and outer diameters of each core sample with machining tolerances in step S2, the outer diameters of the nine inner rings and the inner diameters of the nine outer rings are precisely ground according to the different interference combinations calculated in step S1. At the same time, both ends of the outer circle of each inner ring and the inner circle of each outer ring are lightly chamfered.

[0017] S5. According to each set of inner and outer rings ground on each core sample, nine sets of upper and lower pressure rings are precisely ground;

[0018] S6. Heat-shrunk the nine core samples between the corresponding ground inner and outer rings to obtain nine composite amorphous alloy cores.

[0019] S7. After the hot-jacketed iron core sample cools to room temperature, wind the primary and secondary windings for testing on each set of inner and outer rings of the nine core samples with different interference fits. Wind the primary and secondary windings for testing on the last core sample without the outer and inner rings.

[0020] S8. Use the soft magnetic material magnetic property testing system to test the magnetization and loss characteristics of all iron core samples.

[0021] Preferably, in step S1, the main dimensions of the core sample include outer diameter, inner diameter and axial height.

[0022] Preferably, the process sequence in step S2 includes: cutting, laminating, wire cutting, heat treatment, vacuum dipping, drying and fine grinding.

[0023] Preferably, step S3 is specifically as follows: using a high-precision inside micrometer and a high-precision outside micrometer to measure the main dimensions of each core sample, so as to calculate the magnetic path length, magnetic path cross-sectional area, magnetic field strength and magnetic induction intensity of each core sample during subsequent testing; using a balance to measure the mass of each core sample, so as to calculate the unit mass loss of the core sample.

[0024] Preferably, in step S4, the axial height of each inner ring and outer ring is the same, which is equal to the sum of the axial height of the core sample and the heights of the upper pressure ring and the lower pressure ring.

[0025] Preferably, in step S5, the upper pressure ring and the lower pressure ring are precisely ground to ensure that the outer diameter of each set of upper pressure rings and lower pressure rings is loosely fitted with the inner diameter of the corresponding outer ring, and the inner diameter of each set of upper pressure rings and lower pressure rings is loosely fitted with the outer diameter of the corresponding inner ring.

[0026] The reason for adding non-magnetic upper and lower pressure rings on the upper and lower parts of the core sample is to avoid the outer ring and inner ring generating local axial stress concentration on the outer circle and inner circle edge parts of the core sample respectively during the shrink-fit assembly process in step S6. At the same time, the upper and lower pressure rings will not have an interference fit with the outer ring and the inner ring, which will cause the stress applied to the core sample by the outer ring and the inner ring to deviate significantly from the stress calculated in step S1.

[0027] Preferably, the specific process of step S6 is:

[0028] S61, heating the outer ring of one of the core samples to a temperature lower than the failure temperature of the adhesive used for vacuum impregnation of the core sample in step S2, then aligning the corresponding lower pressure ring, the core sample, and the upper pressure ring from bottom to top, and heat-shrink-fitting the heated outer ring onto the outer sides of the core sample, the upper pressure ring, and the lower pressure ring;

[0029] S62, heating the iron core sample, the upper pressure ring, and the lower pressure ring after being heat-fitted over the outer ring, wherein the heating temperature is lower than the failure temperature of the adhesive used for vacuum impregnation of the iron core sample in step S2, and heat-fitting the heated iron core sample with the outer ring over the outer surface of the corresponding inner ring at room temperature;

[0030] S63, repeat the steps of heat-shrink fitting the outer ring and heat-shrink fitting the inner ring until all nine precision-ground iron core samples are heat-shrink fitted.

[0031] Preferably, the specific process of step S8 is:

[0032] S81. Utilizing a soft magnetic material magnetic property testing system and an amorphous nanocrystal testing method, sequentially test nine core specimens having different combinations of interference fits between the outer and inner rings. Test the loss characteristics and magnetization characteristics of the core specimens under different stresses and frequencies corresponding to all calculated interference fit combinations.

[0033] S82. Using a soft magnetic material magnetic property testing system and an amorphous nanocrystalline testing method, the loss characteristics and magnetization characteristics of the iron core samples without outer and inner rings installed but with primary and secondary windings are tested at different frequencies.

[0034] Therefore, the present invention adopts the above-mentioned stress sensitivity test method of amorphous alloy core loss and magnetization characteristics, which has the following beneficial effects:

[0035] (1) The invention obtains radial stress that is approximately uniformly distributed inside the core sample by changing the interference fit combinations between the titanium alloy outer ring and the titanium alloy inner ring and the core sample; the stress distribution results of the finite element calculation show that by changing the size of the interference fit combination, the radial stress deviation inside the core sample can be kept within 3%.

[0036] (2) This method can relatively accurately obtain the quantitative relationship between the influence of the radial stress with approximately uniform distribution inside the amorphous core sample on the core loss and magnetization characteristics, thereby providing data support for improving the accuracy of the optimized design and performance analysis of amorphous alloy high-speed motors and giving full play to the advantages of low high-frequency loss of amorphous alloys.

[0037] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 Schematic diagram of the structure of a composite amorphous alloy core with primary winding and secondary winding according to an embodiment of the present invention;

[0039] Figure 2 A top view of a composite amorphous alloy core according to an embodiment of the present invention;

[0040] Figure 3 A front cross-sectional view of a composite amorphous alloy core according to an embodiment of the present invention;

[0041] Figure 4 A front cross-sectional view of an iron core sample according to an embodiment of the present invention;

[0042] Figure 5 is a front cross-sectional view of an outer ring according to an embodiment of the present invention;

[0043] Figure 6 is a front cross-sectional view of an inner ring according to an embodiment of the present invention;

[0044] Figure 7 A front cross-sectional view of an upper pressure ring according to an embodiment of the present invention;

[0045] Reference numerals

[0046] 1. Iron core sample; 2. Outer ring; 3. Inner ring; 4. Upper pressure ring; 5. Lower pressure ring; 6. Primary winding; 7. Secondary winding. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0048] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0049] Example 1

[0050] The present invention provides a stress sensitivity test method for loss and magnetization characteristics of an amorphous alloy core, wherein, Figure 1-Figure 7 As shown, the composite amorphous alloy core includes a core sample 1, an outer ring 2, an inner ring 3, an upper pressure ring 4, and a lower pressure ring 5. The inner ring 3 is arranged on the inner side of the core sample 1 and the outer ring 2. The outer sides of the outer ring 2 and the inner ring 3 are wound with a primary winding 6 and a secondary winding 7. The upper pressure ring 4 and the lower pressure ring 5 are arranged in sequence from top to bottom between the outer ring 2 and the inner ring 3. The amorphous core sample 1 is arranged between the upper pressure ring 4 and the lower pressure ring 5. The core sample 1, the outer ring 2, the inner ring 3, the upper pressure ring 4, and the lower pressure ring 5 are all arranged in a circular ring structure. The core sample 1 is an amorphous alloy core sample, and there are 9 of them. The outer ring 2 and the inner ring 3 are both made of titanium alloy material, and the upper pressure ring 4 and the lower pressure ring 5 are made of non-magnetic stainless steel material.

[0051] The stress sensitivity test method includes the following steps:

[0052] S1. Use the finite element method to calculate the stress distribution inside the core sample 1 under different interference combinations of the core sample 1 with different main dimensions and the inner ring 3 and outer ring 2. Select nine sets of interference combinations with the inner ring 3 and outer ring 2 corresponding to different stresses that are approximately uniformly distributed inside the core sample 1 with the same main dimensions. At the same time, obtain the outer diameter and inner diameter dimensions of the core sample 1 when the stress is approximately uniformly distributed. The main dimensions of the core sample 1 include the outer diameter, inner diameter, and axial height. The axial height of the core sample 1 is determined by the output voltage and current of the soft magnetic material magnetic properties test system in step S8, the outer diameter and inner diameter of the core sample 1, and the approximate unit mass loss of the core sample 1. The inner diameter, outer diameter, and axial height of the core sample 1 in this embodiment are 80.0 mm, 90.0 mm, and 10.0 mm, respectively.

[0053] S2. Select an iron-based amorphous alloy strip with a width slightly larger than the outer diameter of the core sample 1 when the stress distribution is approximately uniform in step S1. This iron-based amorphous alloy strip is then processed in the same process sequence to obtain ten core samples 1 having the same major dimensions and machining tolerances as in step S1. This allows for comparative testing of loss and magnetization properties using one of the core samples 1 without any interference. The iron-based amorphous alloy strip used in this embodiment is 1K101 strip with a width of 100 mm, which is currently available.

[0054] The process sequence includes: cutting, lamination, wire cutting, heat treatment, vacuum dipping, drying and fine grinding.

[0055] S3. Use high-precision inside micrometer and outside micrometer to accurately measure the main dimensions of each iron core sample 1, so as to subsequently calculate the magnetic path length, magnetic path cross-sectional area, magnetic field strength and magnetic induction strength of each iron core sample 1; use a balance to measure the mass of each iron core sample 1, so as to subsequently calculate the unit mass loss of the iron core sample 1.

[0056] S4. According to the interference combination of the outer ring 2 and the inner ring 3 calculated in step S1, according to the inner diameter and outer diameter of each core sample 1 with processing tolerance in step S2, the outer diameter of each inner ring 3 and the inner diameter of each outer ring 2 are respectively ground correspondingly, and at the same time, the outer circle of each inner ring 3 and the inner circle of each outer ring 2 are slightly chamfered at both ends to facilitate the subsequent shrink fit of each core sample 1; wherein the axial height of each inner ring 3 and the outer ring 2 are the same, which is equal to the sum of the axial height of the core sample 1 and the height of the upper pressure ring 4 and the lower pressure ring 5.

[0057] S5. According to each set of inner rings 3 and outer rings 2 that have been ground on each core sample 1, the upper pressure ring 4 and the lower pressure ring 5 are precisely ground to ensure that the outer diameter of each set of upper pressure rings 4 and lower pressure rings 5 ​​are loosely matched with the inner diameter of the corresponding outer ring 2, and the inner diameter of each set of upper pressure rings 4 and lower pressure rings 5 ​​are loosely matched with the outer diameter of the corresponding inner ring 3. The purpose of grinding the upper pressure ring 4 and the lower pressure ring 5 is to prevent the outer ring 2 and the inner ring 3 from applying local axial concentrated stress to the outer circle and inner circle edges of the core sample 1 respectively during the subsequent shrink-fit process. Instead, the axial stress during shrink-fit is evenly applied to the core sample 1 through the upper pressure ring 4 and the lower pressure ring 5. At the same time, the inner circle of the outer ring 2 and the outer circle of the inner ring 3 will not apply radial stress to the upper pressure ring 4 and the lower pressure ring 5, thereby avoiding a large deviation between the stress applied to the core sample 1 and the stress calculated in step S1.

[0058] S6. Perform heat-shrink installation on the nine core samples respectively, and then obtain nine composite amorphous alloy cores.

[0059] In this embodiment, the specific process of step S6 is:

[0060] S61. Heat the outer ring 2 that is ground with one of the core samples 2. The heating temperature is lower than the failure temperature of the adhesive used for vacuum impregnation of the core sample 1 in step S2. Then align the corresponding lower pressure ring 5, the core sample 1, and the upper pressure ring 4 from bottom to top in sequence. Heat-slip the heated outer ring 2 on the outside of the core sample 1, the upper pressure ring 4, and the lower pressure ring 5.

[0061] S62. Heat the iron core sample 1 and the upper and lower pressure rings 4 and 5 that are heat-fitted through the outer ring 2. The heating temperature is lower than the failure temperature of the adhesive used for vacuum impregnation of the iron core sample 1 in step S2. Heat-fit the heated iron core sample 1 with the outer ring 2 onto the outside of the corresponding inner ring 3 at room temperature.

[0062] S63, repeat the steps of heat-shrink fitting the outer ring 2 and heat-shrink fitting the inner ring 3 until all nine precision-ground iron core samples 1 are heat-shrink fitted.

[0063] S7. After the hot-jacketed iron core sample 1 cools to room temperature, a primary winding 6 and a secondary winding 7 for testing are wound on each of the nine sets of inner rings 3 and outer rings 2 with different interference fits and on which the iron core sample 1 is installed; a primary winding 6 and a secondary winding 7 for testing are also wound on the last iron core sample 1 that does not have an outer ring 2 and an inner ring 3 installed.

[0064] S8. Use the soft magnetic material magnetic property testing system to test all core samples.

[0065] In this embodiment, the specific process of step S8 is:

[0066] S81. Using a soft magnetic material magnetic property testing system and in accordance with the amorphous nanocrystal testing method in the national standard "GB / T19346.1-2017 Test Method for Amorphous Nanocrystals Part 1: AC Magnetic Properties of Ring-Shaped Specimens", nine core specimens 1 with different interference fit combinations between the outer ring 2 and the inner ring 3 are tested in turn. The loss characteristics and magnetization characteristics of the core specimens 1 corresponding to all calculated interference fit combinations are tested at different stresses and different frequencies.

[0067] S82. Using a soft magnetic material magnetic property testing system and the amorphous nanocrystal testing method in step S81, the core sample 1 without the outer ring 2 and the inner ring 3 but with the primary winding 6 and the secondary winding 7 is tested for loss characteristics and magnetization characteristics at different frequencies.

[0068] Example 2

[0069] The iron core sample 1 to be tested is set to be any one of a nanocrystalline laminated iron core, a Permalloy laminated iron core, a soft magnetic cobalt-vanadium alloy laminated iron core or a silicon steel sheet laminated iron core, and the rest of the specific implementation methods are the same as those in Example 1.

[0070] Therefore, the present invention adopts the above-mentioned stress sensitivity test method of amorphous alloy core loss and magnetization characteristics, which can more accurately obtain the quantitative relationship between the influence of the approximately uniformly distributed radial stress inside the amorphous core sample on the core loss and magnetization characteristics, thereby providing data support for improving the accuracy of the optimized design and performance analysis of amorphous alloy high-speed motors.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the same. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solutions of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A stress sensitivity test method for loss and magnetization characteristics of an amorphous alloy core, characterized in that: The following steps are involved: S1. Use the finite element method to calculate the stress distribution inside annular iron core specimens of different main dimensions and under different interference combinations of the inner and outer rings. Select nine sets of interference combinations corresponding to different stresses that are approximately uniformly distributed inside the iron core specimens with the same main dimensions. At the same time, obtain the outer and inner diameter dimensions of the iron core specimens when the stress is approximately uniformly distributed. The iron core specimens are amorphous alloy specimens, the inner and outer rings are both made of titanium alloy, and the upper and lower pressure rings are made of non-magnetic stainless steel. S2. Select an iron-based amorphous alloy strip having a width greater than the outer diameter of the iron core sample when the stress is approximately uniformly distributed in step S1, and process the iron-based amorphous alloy strip at one time according to the same process sequence to obtain ten annular iron core samples having the same main dimensions as in step S1; S3. Use high-precision inside micrometer, high-precision outside micrometer and balance to test each core sample; S4. According to the interference combinations of the outer and inner rings calculated in step S1, and based on the inner and outer diameters of each core sample with machining tolerances in step S2, the outer diameters of the nine inner rings and the inner diameters of the nine outer rings are precisely ground according to the different interference combinations calculated in step S1, and at the same time, both ends of the outer circle of each inner ring and the inner circle of each outer ring are chamfered; S5. According to each set of inner and outer rings ground on each core sample, nine sets of upper and lower pressure rings are precisely ground; S6. Heat-shrunk the nine core samples between the corresponding ground inner and outer rings to obtain nine composite amorphous alloy cores. S7. After the hot-jacketed iron core sample cools to room temperature, wind the primary and secondary windings for testing on each set of inner and outer rings of the nine core samples with different interference fits. Wind the primary and secondary windings for testing on the last core sample without the outer and inner rings. S8. Use the soft magnetic material magnetic property testing system to test the magnetization and loss characteristics of all iron core samples.

2. The stress sensitivity testing method for loss and magnetization characteristics of an amorphous alloy core according to claim 1, characterized in that: In step S1 , the main dimensions of the core sample include outer diameter, inner diameter and axial height.

3. The stress sensitivity testing method for loss and magnetization characteristics of an amorphous alloy core according to claim 1, characterized in that: The process sequence in step S2 includes: cutting, laminating, wire cutting, heat treatment, vacuum dipping, drying and fine grinding.

4. The stress sensitivity testing method for loss and magnetization characteristics of an amorphous alloy core according to claim 1, characterized in that: Step S3 specifically includes: using a high-precision inside micrometer and a high-precision outside micrometer to measure the main dimensions of each core sample in order to calculate the magnetic path length, magnetic path cross-sectional area, magnetic field strength and magnetic induction intensity during subsequent tests of each core sample; using a balance to measure the mass of each core sample in order to calculate the unit mass loss of the core sample.

5. The stress sensitivity testing method for loss and magnetization characteristics of an amorphous alloy core according to claim 1, characterized in that: In step S4, the axial heights of each inner ring and outer ring are the same, which is equal to the sum of the axial height of the core sample and the heights of the upper pressure ring and the lower pressure ring.

6. The stress sensitivity testing method for loss and magnetization characteristics of an amorphous alloy core according to claim 1, characterized in that: In step S5, the upper and lower pressure rings are precisely ground to ensure that the outer diameter of each set of upper and lower pressure rings is loosely fitted with the inner diameter of the corresponding outer ring, and the inner diameter of each set of upper and lower pressure rings is loosely fitted with the outer diameter of the corresponding inner ring.

7. The stress sensitivity testing method for loss and magnetization characteristics of an amorphous alloy core according to claim 3, characterized in that: The specific process of step S6 is: S61, heating the outer ring of one of the core samples to a temperature lower than the failure temperature of the adhesive used for vacuum impregnation of the core sample in step S2, then aligning the corresponding lower pressure ring, the core sample, and the upper pressure ring from bottom to top, and heat-shrink-fitting the heated outer ring onto the outer sides of the core sample, the upper pressure ring, and the lower pressure ring; S62, heating the iron core sample, the upper pressure ring, and the lower pressure ring after being heat-fitted over the outer ring, wherein the heating temperature is lower than the failure temperature of the adhesive used for vacuum impregnation of the iron core sample in step S2, and heat-fitting the heated iron core sample with the outer ring over the outer surface of the corresponding inner ring at room temperature; S63, repeat the steps of heat-shrink fitting the outer ring and heat-shrink fitting the inner ring until all nine precision-ground iron core samples are heat-shrink fitted.

8. The stress sensitivity testing method for loss and magnetization characteristics of an amorphous alloy core according to claim 1, characterized in that: The specific process of step S8 is: S81. Using a soft magnetic material magnetic property testing system and an amorphous nanocrystal testing method, sequentially test nine core specimens having different combinations of interference fits between the outer and inner rings. Test the loss characteristics and magnetization characteristics of the core specimens under different stresses and frequencies corresponding to all calculated interference fit combinations. S82. Using a soft magnetic material magnetic property testing system and an amorphous nanocrystalline testing method, the loss characteristics and magnetization characteristics of the iron core samples without outer and inner rings installed but with primary and secondary windings are tested at different frequencies.

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