Permanent magnet motor test platform and method with adjustable demagnetization fault mode

Abstract

The invention discloses a demagnetization fault mode adjustable permanent magnet motor test platform and method, and belongs to the technical field of permanent magnet motor demagnetization. The platform comprises a base, a guide rail, an electric lead screw module, a bearing supporting seat, a motor shaft, a tested motor with an adjustable demagnetization fault mode, a coupler, a torque sensor, a base of the torque sensor, a load motor or a magnetic powder brake, a motor base and a sliding block. The rotor of the tested motor adopts a dovetail groove guide rail structure, and the permanent magnet can be conveniently replaced through the embedded matching of the notch on the rotor iron core and the dovetail iron block assembly. The electric lead screw module drives the stator to move axially, and the coupling position of the stator and the rotor iron core module is adjusted. The platform flexibly simulates uniform or local demagnetization faults by adjusting the sizes and positions of the permanent magnets in the X, Y and Z directions. Compared with traditional equipment, the platform is low in cost, simple in structure, high in experiment flexibility and suitable for diversified demagnetization fault research.

Description

Technical Field

[0001] The present invention belongs to the technical field of permanent magnet motor demagnetization, and in particular relates to a permanent magnet motor test platform and method with adjustable demagnetization fault mode. Background Art

[0002] Permanent magnet motors are widely used in aerospace, shipbuilding and marine engineering equipment, robots, advanced rail transportation equipment, electric vehicles, high-end CNC machine tools and other fields due to their high power density, high efficiency and easy control. Permanent magnets are the source of the magnetic field in permanent magnet motors, and their performance directly affects the performance of permanent magnet motors. However, affected by factors such as high temperature, armature reaction, acid and alkali corrosion, permanent magnets are prone to demagnetization failures. Demagnetization failures not only affect the performance of the motor itself, but also cause the failure of the system driven by the motor, and even cause catastrophic accidents. Demagnetization fault diagnosis is an important means to improve the reliability, safety and economy of motors and their systems. Among them, experimental research plays an important role in revealing the mechanism of demagnetization failure, evaluating the impact of demagnetization failure, verifying and optimizing demagnetization fault models and diagnostic methods, and thus becomes an indispensable method for studying demagnetization failures. The demagnetization fault motor test platform is an important device for experimental research on demagnetization failures, so its development has become a hot topic of research at home and abroad.

[0003] The different arrangements and combinations of demagnetization permanent magnets in terms of quantity, position and degree make the demagnetization failure modes of permanent magnet motors diverse. In order to conduct experimental research on a variety of different demagnetization failure modes, some scholars have built multiple demagnetization failure motor test platforms to simulate different demagnetization failure modes. However, since each test platform needs to be equipped with complete equipment, including demagnetization failure motors, healthy motors, speed torque measuring instruments, voltage sensors, etc., the purchase of these equipment requires a large amount of money. Therefore, this research method has a significant defect of high cost, especially when a large amount of test data of different demagnetization failure modes needs to be obtained to support the research, this shortcoming becomes particularly prominent, making the entire research process face greater economic pressure. In order to reduce the research cost, some scholars built a demagnetization failure motor test platform, and realized the experimental research of different demagnetization failure modes by replacing motors with different demagnetization failure modes. Compared with building multiple complete test platforms, this method can indeed save the investment in healthy motors and test equipment and reduce some costs. However, it requires the production of multiple motors with different demagnetization failure modes, so it still has the disadvantage of high cost, and also faces the problem of difficult installation and debugging. In order to further reduce the research cost, some scholars have built a demagnetization fault motor test platform, manufactured a demagnetization fault motor and multiple rotors with different demagnetization fault modes, and used the method of replacing the rotor to study different demagnetization fault modes. However, due to the strong suction between the stator and the rotor during the assembly process of the permanent magnet motor, special installation tools are required to ensure the accuracy and safety of the assembly. In places such as schools where there are no special tools, researchers have to send the motor and rotor back to the manufacturer for replacement, which undoubtedly increases the difficulty of installation and debugging. At the same time, the cost problem of this method is still prominent. Summary of the invention

[0004] In view of the problems existing in the prior art, the present invention provides a permanent magnet motor testing platform and method with adjustable demagnetization fault mode.

[0005] The present invention is implemented as follows: a permanent magnet motor test platform with adjustable demagnetization fault mode, the platform comprising a platform base 1, a guide rail 2, an electric screw module 3 for adjusting the position of the motor rotor under test, a bearing support seat 4, a motor shaft 5, a motor under test 6, a coupling 7, a torque sensor 8, a torque sensor base 9, a motor 10 or a magnetic powder brake for simulating the load of the motor under test, a motor base 11, and a slider 12;

[0006] The electric screw module 3 for adjusting the rotor position of the motor under test includes a ball screw motor 13, a screw fixing seat 14, a nut connecting seat 15, a screw nut 16, a screw 17, and a screw support seat 18;

[0007] The ball screw motor 13 drives the screw shaft to rotate. As the screw shaft rotates, the screw nut moves smoothly along the spiral path of the screw, thereby accurately driving the stator of the motor under test to achieve axial displacement; the motor base 11 and the torque sensor base 9 are connected to the slider 12 through screws 19.

[0008] Furthermore, the motor 6 under test is composed of a front end cover 20, a bearing seat 21, a sleeve 22 that supports the bearing to move in two degrees of freedom, radial and axial, a first rotor fixing part 23, a rotor core module 24 using a dovetail groove guide structure (a T-slot guide structure may also be used), a second rotor fixing part 26, a stator core and winding 27, a machine base 28, a rear end cover 29, etc.

[0009] Furthermore, the rotor core module 24 adopting the dovetail groove guide structure is composed of a rotor core 30 with a dovetail groove notch and a dovetail iron block assembly 31; through the interlocking cooperation between the notch on the rotor core and the dovetail iron block assembly, the dovetail iron block assembly can be pulled out and inserted from the rotor core, thereby facilitating the replacement of the rotor permanent magnet.

[0010] Furthermore, the dovetail iron block assembly 31 is composed of a dovetail iron block 32 and a permanent magnet 25; wherein the permanent magnet of the surface-mounted permanent magnet motor is attached to the dovetail iron block, and the permanent magnet of the built-in permanent magnet motor is embedded inside the dovetail iron block. The size of the dovetail iron block can be slightly larger than k times the pole pitch, where k is a natural number and can be 1, 2, 3..., 2p; the number of permanent magnets attached to the dovetail iron block depends on the motor structural parameters, and there are cases where one permanent magnet is attached, and there are also cases where multiple permanent magnets are attached, such as Figure 7 shown.

[0011] Furthermore, the dimensions of the permanent magnet 25 in the three directions of X, Y and Z are adjustable to simulate different local demagnetization faults of a single permanent magnet; in the simulation of the demagnetization of the permanent magnet in the Z direction, the dimension of the axial length of the permanent magnet in the Z direction is changed to be smaller than the dimension of a healthy permanent magnet; in the simulation of the demagnetization of the permanent magnet in the Y direction, the dimension of the arc length of the permanent magnet in the Y direction is changed to be smaller than the dimension of a healthy permanent magnet; in the simulation of the demagnetization of the permanent magnet in the X direction, the X direction is radial, that is, the dimension of changing the thickness of the permanent magnet is smaller than the dimension of a healthy permanent magnet; in the simulation of the demagnetization of the permanent magnet in the X, Y and Z directions, the dimensions of the permanent magnet in the X, Y and Z directions are all smaller than the dimensions of a healthy permanent magnet; demagnetization of any shape can also be simulated.

[0012] Furthermore, the axially adjustable length of the measured motor 6 is twice the length of the rotor; the length of the measured motor shaft and the length of the base are both more than twice the length of the corresponding parts of the same model motor; when the lead screw motor drives the lead screw shaft to rotate, the lead screw nut drives the stator of the measured motor to move axially, and this design can not only realize the simulation of uniform demagnetization fault but also provide conditions for the adjustment of demagnetization fault mode; when the stator moves to partially couple with the rotor, the simulation of uniform demagnetization fault is realized; when the rotor is completely moved out, the rotor permanent magnet can be replaced, thereby realizing the adjustment of the demagnetization fault mode.

[0013] In combination with the above technical solutions and the technical problems solved, the advantages and positive effects of the technical solutions to be protected by the present invention are as follows:

[0014] First, the present invention proposes a motor test platform with adjustable demagnetization fault mode, which can simulate a variety of different demagnetization fault modes in a lower cost and more convenient way, and realizes flexible simulation and experimental research on demagnetization fault modes.

[0015] The technical solution of the present invention has a wide range of application potential, and is particularly suitable for motor manufacturing enterprises, higher education institutions and other related fields for testing the demagnetization of permanent magnet motors. After the technical solution of the present invention is successfully transformed and implemented, it can solve the technical problems encountered in experimental research of various demagnetization failure modes. This not only provides strong technical support for related enterprises, helping them to establish an outstanding technological leadership in the industry, but also enhances their ability to attract potential partners and investors. For example, a 10kW 66-pole 72-slot direct-drive permanent magnet synchronous motor has a single market price of 30,000 yuan. The price of a single rotor component of the motor is 12,000 yuan, and the price of a single dovetail iron block assembly is 10,000 yuan. It can be seen that the motor faces a variety of demagnetization failure risks. When conducting relevant experimental studies on demagnetization failures, the cost of replacing the dovetail core assembly alone is much lower than replacing the entire rotor or the entire motor. Therefore, the technical solution proposed by the present invention, after the transformation and application, is not only expected to have rich returns, but also has good commercial development prospects.

[0016] The present invention also solves the problem of high experimental research costs caused by the need to manufacture multiple demagnetization fault prototypes or multiple demagnetization rotors for experimental research on a variety of different demagnetization failure modes.

[0017] Second, the technical problems solved by the technical solution of the present invention in industrial applications and the significant technical progress brought about are as follows:

[0018] Technical problems solved by the present invention:

[0019] 1. Limited research methods for demagnetization failures and insufficient simulation accuracy

[0020] In the existing technology, it is difficult to achieve flexible simulation of uniform demagnetization and local demagnetization when studying the demagnetization failure of permanent magnet motors, especially the poor reproduction ability of complex failure modes, which limits the breadth and depth of research. The present invention realizes high-precision simulation of different demagnetization modes (radial, tangential, axial and their combination) through the dovetail slot structure and the adjustable design of the shape and size of the permanent magnet, which makes up for the shortcomings of the existing experimental equipment.

[0021] 2. Demagnetization fault test equipment is complex and costly

[0022] Traditional demagnetization fault test systems are often complex, costly, and inflexible, making it difficult to meet diverse experimental needs. The present invention adopts a modular design, using a simple and reusable dovetail iron block assembly combined with an electric screw module to achieve low-cost, highly flexible demagnetization fault simulation and testing.

[0023] 3. The test platform has a single function and cannot support comprehensive performance analysis

[0024] Existing test platforms can usually only collect limited operating data and cannot comprehensively evaluate the comprehensive impact of demagnetization faults on the performance of permanent magnet motors. The present invention integrates multiple test equipment such as torque sensors, voltage and current sensors, and combines simulated load equipment to achieve real-time collection and analysis of multi-dimensional data such as torque, voltage, and current in demagnetization mode, providing more comprehensive data support for motor performance research.

[0025] Significant technical advancements of the present invention:

[0026] 1. The flexibility of demagnetization mode simulation is significantly improved

[0027] The present invention can flexibly simulate uniform demagnetization and local demagnetization modes, as well as complex mixed demagnetization modes, through the pluggable design of the dovetail iron block assembly and the multi-directional adjustment of the permanent magnet size (X, Y, and Z directions). This high flexibility provides a new means for the study of diversified demagnetization faults.

[0028] 2. Improvement of test accuracy and experimental efficiency

[0029] Through the precise position control of the electric screw module, the high-precision adjustment of the coupling position of the stator and the rotor is achieved, and different test conditions can be quickly switched to improve the experimental efficiency. At the same time, the test data is collected in real time through high-precision sensors to ensure the reliability and accuracy of the research results.

[0030] 3. Cost-effectiveness and system simplification

[0031] Compared with traditional demagnetization test equipment, the present invention has a simple structure design and modular core components, which significantly reduces manufacturing and maintenance costs. The reusability of the dovetail iron block assembly and the electric screw module makes the application of the test platform in different experimental scenarios more economical and efficient.

[0032] 4. Promote the industrial application of research on permanent magnet motor demagnetization failure

[0033] The present invention is not only suitable for laboratory research, but also can be widely used in the design verification, fault diagnosis and operation maintenance of permanent magnet motors. The multi-dimensional data analysis capability provided by the test platform provides a scientific basis for the early detection of demagnetization faults and the optimization of operating performance in practical applications, and has important industrial promotion value.

[0034] In summary, the present invention has made significant progress in the flexibility of demagnetization fault simulation, experimental cost and efficiency, data acquisition and analysis capabilities, etc., solved the key bottlenecks of the prior art, and promoted the in-depth development and application of permanent magnet motor demagnetization fault research. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a structural diagram of a permanent magnet motor test platform with adjustable demagnetization fault mode;

[0036] Figure 2 It is an electric ball screw module that adjusts the rotor position of the motor being tested;

[0037] Figure 3 It is the motor base, torque sensor base and slider;

[0038] Figure 4 It is an exploded diagram of a permanent magnet motor with adjustable demagnetization failure mode;

[0039] Figure 5 It is a rotor core module with dovetail groove guide structure;

[0040] Figure 6 It is a rotor core module that adopts T-slot guide rail structure;

[0041] Figure 7 This is an example of a dovetail iron block assembly with one permanent magnet and multiple permanent magnets attached;

[0042] Figure 8 It is a dovetail iron block assembly with a single healthy permanent magnet attached;

[0043] Fig. 9 This is an example of a dovetail iron block assembly with 25% demagnetization in the Z direction;

[0044] Fig.10 This is an example of a dovetail iron block assembly with 50% demagnetization in the Z direction;

[0045] Fig.11This is an example of a dovetail iron block assembly with 75% demagnetization in the Z direction;

[0046] Fig.12 This is an example of a dovetail iron block assembly with 20% demagnetization in the Y direction;

[0047] Fig.13 This is an example of a dovetail iron block assembly with 40% demagnetization in the Y direction;

[0048] Fig.14 This is an example of a dovetail iron block assembly with 60% demagnetization in the Y direction;

[0049] Fig.15 This is an example of a dovetail iron block assembly with 80% demagnetization in the Y direction;

[0050] Fig.16 This is an example of a dovetail iron block assembly that is demagnetized 80% in the X direction (the direction of the permanent magnet thickness);

[0051] Fig.17 This is an example of the front view of the dovetail iron block assembly with 80% demagnetization in the X direction;

[0052] Fig.18 This is an example of the front view, left view and stereogram of a dovetail iron block assembly with 80% demagnetization in the X direction, 25% demagnetization in the Y direction and 25% demagnetization in the Z direction;

[0053] Fig.19 This is an example of a dovetail iron block assembly where a single permanent magnet undergoes arbitrary shape demagnetization;

[0054] Fig. 20 The stator and rotor core modules of the motor under test are fully coupled;

[0055] Fig.21 It is the coupling between the stator and rotor core modules of the motor under test;

[0056] Fig. 22 The rotor core module of the motor under test is completely removed;

[0057] Fig.23 It is a healthy rotor core module;

[0058] Fig.24 It is a variety of dovetail iron block components with demagnetized permanent magnets glued to them;

[0059] Fig.25 is an example of a dovetail iron block assembly that can simulate the demagnetization failure mode of a single permanent magnet;

[0060] Fig.26 This is an example of a dovetail iron block assembly that can simulate the demagnetization failure mode of two adjacent permanent magnets;

[0061] Fig. 27This is an example of a dovetail iron block assembly that can simulate the demagnetization failure mode of two demagnetized permanent magnets separated by a healthy permanent magnet;

[0062] Fig.28 An example of a dovetail iron assembly that can simulate the failure mode of demagnetization of 3 permanent magnets. DETAILED DESCRIPTION

[0063] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0064] The embodiment of the present invention provides a permanent magnet motor test platform with adjustable demagnetization fault mode, which is used to simulate and test the performance of the same permanent magnet motor under multiple different demagnetization fault modes. Figure 1 As shown, it includes a platform base 1, a guide rail 2, an electric screw module 3 for adjusting the rotor position of the motor under test, a bearing support seat 4, a motor shaft 5, a motor under test 6, a coupling 7, a torque sensor 8, a torque sensor base 9, a motor 10 for simulating the load of the motor under test (the load of the motor under test is not limited to the motor, but can also be a magnetic powder brake), a motor base 11, and a slider 12. Among them, the electric screw module for adjusting the rotor position of the motor under test is as shown in FIG. Figure 2 As shown, it includes a ball screw motor 13, a screw fixing seat 14, a nut connection seat (nut seat) 15, a screw nut 16, a screw 17, and a screw support seat 18. The screw motor drives the screw shaft to rotate. As the screw shaft rotates, the screw nut moves smoothly along the spiral path of the screw, thereby accurately driving the stator of the motor under test to achieve axial displacement. The motor base and the torque sensor base are connected to the slider through screws 19.

[0065] The motor under test is Figure 4 As shown in FIG. 1 , the rotor core module 24 is composed of a front end cover 20, a bearing seat 21, a sleeve 22 for supporting the bearing to move in two degrees of freedom, radial and axial, a first rotor fixing member 23, a rotor core module 24 with a dovetail groove guide structure, a second rotor fixing member 26, a stator core and winding 27, a base 28, and a rear end cover 29. The rotor core module with a dovetail groove guide structure is shown in FIG. Figure 5 As shown (not limited to dovetail grooves, there is also a T-slot 30'+T-shaped iron block assembly 31' structure, such as Figure 6 As shown in FIG. 1 , the rotor core 30 is composed of an iron core 30 with a dovetail slot and a dovetail iron block assembly 31. The dovetail iron block assembly can be pulled out and inserted from the rotor core by the notch on the rotor core and the dovetail iron block assembly, so that the rotor permanent magnet can be easily replaced. Figure 7As shown, it is composed of a dovetail iron block 32 and a permanent magnet 25; wherein, the permanent magnet of the surface-mounted permanent magnet motor is attached to the dovetail iron block, and the permanent magnet of the built-in permanent magnet motor is embedded inside the dovetail iron block. The size of the dovetail iron block can be slightly larger than k times the pole pitch (k is a natural number, which can be 1, 2, 3..., 2p). The number of permanent magnets attached to the dovetail iron block depends on the motor structural parameters. There are cases where one permanent magnet is attached, and there are also cases where multiple permanent magnets are attached, such as Figure 7 shown.

[0066] The dimensions of a single permanent magnet in the three directions of X, Y, and Z are adjustable to simulate different local demagnetization failures of a single permanent magnet. Figure 8 As shown in the figure, the simulation of the demagnetization of the permanent magnet in the Z direction shows that the size of the permanent magnet in the Z direction (changing the axial length of the permanent magnet) is smaller than that of the healthy permanent magnet. Fig. 9 ), 50% (as shown), Fig.10 ), 75% (as shown), Fig.11 The simulation of the demagnetization of the permanent magnet in the Y direction shows that the size of the permanent magnet in the Y direction (changing the arc length of the permanent magnet) is smaller than the size of the healthy permanent magnet. For example, the permanent magnet is demagnetized by 20% at different positions along the Y direction (such as Fig.12 ), 40% (as shown), Fig.13 ), 60% (as shown), Fig.14 As shown), 80% (as shown Fig.15 The simulation of the demagnetization of the permanent magnet in the X direction shows that the size of the permanent magnet in the X direction (radial direction, i.e., the thickness of the permanent magnet) is smaller than that of the healthy permanent magnet. For example, the permanent magnet is demagnetized by 80% in the X direction (stereoscopic diagram as shown in Fig.16 As shown, the main view is Fig.17 As shown). The permanent magnet is demagnetized in the three directions of X, Y and Z. Its dimensions in the three directions of X, Y and Z are all smaller than those of a healthy permanent magnet. For example, the permanent magnet is demagnetized by 80% in the X direction, 25% in the Y direction, and 25% in the Z direction. Fig.18 It is also possible to simulate the demagnetization of arbitrary shapes, such as Fig.19 shown.

[0067] The adjustable axial length of the motor under test is twice the length of the rotor. The length of the motor shaft and the length of the motor base under test are both more than twice the length of the corresponding parts of the motor of the same model. When the lead screw motor drives the lead screw shaft to rotate, the lead screw nut drives the stator of the motor under test to move axially. This design can not only simulate the uniform demagnetization fault but also provide conditions for the adjustment of the demagnetization fault mode. Fig.21 This is the case when the stator is fully coupled with the rotor core module. When the stator moves to a partial coupling with the rotor core module, the simulation of uniform demagnetization fault is realized, such as Fig. 22When the rotor core module is completely removed, the rotor permanent magnet can be replaced, thereby adjusting the demagnetization fault mode, as shown in FIG. Fig.23 shown.

[0068] Determine the size of the permanent magnets on the dovetail iron block assemblies at different positions of the rotor according to the demagnetization fault mode to be simulated, and insert the dovetail iron block assemblies into the slots of the rotor dovetail slots accordingly. For a healthy rotor, all permanent magnets on the dovetail iron block assemblies are healthy. Fig.23 To simulate the failure mode of a single permanent magnet with 30% axial demagnetization, it is only necessary to Fig.24 This can be achieved by replacing the dovetail iron block assembly numbered d-1 (the permanent magnet on this assembly has been pre-cut 30% in the axial direction) with any dovetail iron block assembly numbered on the rotor. Fig.23 Pull out the dovetail iron block assembly numbered h-1, and insert the dovetail iron block assembly numbered d-1. Fig.25 To simulate the failure mode of two permanent magnets being demagnetized (for example, one permanent magnet is axially demagnetized by 25% and the other permanent magnet is radially demagnetized by 40%), we only need to Fig.24 The dovetail iron block assembly numbered d-2 (the permanent magnet on this assembly has been pre-cut 25% in the axial direction) and the dovetail iron block assembly numbered d-3 (the permanent magnet on this assembly has been pre-cut 40% in the radial direction) can replace any two dovetail iron block assemblies of the healthy motor to simulate different failure modes when two permanent magnets are demagnetized. For example, to simulate the failure mode of two adjacent permanent magnets demagnetizing, the dovetail iron block assembly numbered d-2 and the dovetail iron block assembly numbered d-3 can be replaced respectively. Fig.23 In the h-1 component and h-2 component, such as Fig.26 As shown; to simulate the demagnetization failure mode of two demagnetized permanent magnets separated by a healthy permanent magnet, the dovetail iron block assembly numbered d-2 and the dovetail iron block assembly numbered d-3 can be replaced respectively Fig.23 In the h-1 and h-3 components, such as Fig. 27 As shown; by analogy, the failure mode of two permanent magnets demagnetizing in different demagnetization directions, different demagnetization degrees and different spacing distances can also be simulated, which can be achieved by simply replacing the dovetail iron block components at the corresponding positions. In order to simulate the failure mode of three permanent magnets demagnetizing (one permanent magnet axially demagnetized 50%, one permanent magnet radially demagnetized 80%, and another permanent magnet circumferentially demagnetized 60%), only need to Fig.25The dovetail iron block assembly numbered d-4 (on which the permanent magnet has been pre-cut 50% in the axial direction), the dovetail iron block assembly numbered d-5 (on which the permanent magnet has been pre-cut 80% in the radial direction), and the dovetail iron block assembly numbered d-6 (on which the permanent magnet has been pre-cut 60% in the circumferential direction) in the healthy motor can be replaced with any three dovetail iron block assemblies in the healthy motor to simulate different demagnetization failure modes of the three permanent magnets. Fig.23 The dovetail iron block assemblies of h-1, h-3, and h-8 are used to simulate a failure mode of demagnetization of three permanent magnets, such as Fig.28 By analogy, any demagnetization degree, any position, and any number of permanent magnet demagnetization faults can be simulated by simply replacing the dovetail iron block assembly at the corresponding position.

[0069] The present invention provides a simulation test method for a permanent magnet motor demagnetization fault, the method comprising the following steps:

[0070] a) installing the motor under test (6) on a permanent magnet motor test platform with adjustable demagnetization fault mode, and adjusting the stator position of the motor under test by means of an electric screw module (3) so that the stator moves axially to a predetermined test position;

[0071] b) starting a torque sensor (8) and a motor (10) or a magnetic powder brake simulating a load in a test platform to obtain torque data of the motor under different load conditions;

[0072] c) driving the lead screw nut (16) to move by means of the electric lead screw module (3), thereby adjusting the position of the stator of the motor under test in the axial direction, and simulating different uniform demagnetization faults.

[0073] The method further comprises the following steps:

[0074] d) According to the demagnetization experimental research requirements of the motor under test, the dovetail iron block assembly (31) in the rotor core module (24) is pulled out or inserted, and the shape and size of the permanent magnets (25) on the dovetail iron block assembly at different positions are adjusted to simulate different demagnetization modes, so as to test the working performance of the motor under test in different demagnetization modes.

[0075] The adjustment of the shape and size of the permanent magnet on the dovetail iron block assembly in step d includes adjusting the size of the permanent magnet (25) in the X, Y, and Z directions, specifically including:

[0076] Adjust the thickness of the permanent magnet in the X direction to simulate radial demagnetization;

[0077] Adjust the arc length of the permanent magnet in the Y direction to simulate tangential demagnetization;

[0078] The axial length of the permanent magnet in the Z direction is adjusted to simulate axial demagnetization;

[0079] According to actual needs, select the combined adjustment of the three directions of X, Y and Z to achieve complex local demagnetization fault simulation.

[0080] The method further comprises the following steps:

[0081] e) using a torque sensor (8) to collect data such as torque under different demagnetization modes (adding other test equipment such as a voltage sensor, a current sensor, an oscilloscope, etc. can also measure signals such as voltage and current), and combining the feedback data of the load motor (10) or the magnetic powder brake to analyze the influence of different demagnetization modes on the output performance of the motor, and obtain the influence of the demagnetization fault on the electromagnetic characteristics of the permanent magnet motor.

[0082] Specific embodiment 1: Simulation and testing of uniform radial demagnetization fault

[0083] 1. Installation and adjustment

[0084] The motor to be tested is installed on the test platform, and the axial position of the stator is adjusted to the predetermined test position through the electric screw module to ensure that the gap between the rotor and the stator is uniform.

[0085] 2. Demagnetization mode setting

[0086] A number of dovetail iron block assemblies are uniformly pulled out from the rotor core module, and the thickness of the permanent magnets (in the X direction) on the dovetail iron block assemblies is adjusted to a predetermined value to simulate a uniform radial demagnetization mode.

[0087] 3. Data collection and analysis

[0088] The torque sensor and magnetic powder brake in the start-up platform are used to simulate different load conditions. The torque, output voltage and current data are collected to analyze the effect of uniform radial demagnetization on the motor output performance. The experimental results show that uniform radial demagnetization will reduce the torque output of the motor and cause the motor's operating efficiency to decrease.

[0089] Specific embodiment 2: simulation and test of local mixed demagnetization fault

[0090] 1. Installation and adjustment

[0091] The motor under test is mounted on the test platform, the electric lead screw module is started, and the stator is adjusted to the specified test position, ensuring precise alignment between the torque sensor and the load device.

[0092] 2. Demagnetization mode setting

[0093] Pull out some dovetail iron block components from the rotor core module and adjust the size of the permanent magnet at a specific position:

[0094] Adjust the thickness in the X direction to achieve radial demagnetization;

[0095] The arc length in the Y direction was adjusted to simulate tangential demagnetization;

[0096] The axial length in the Z direction is adjusted at other locations to introduce axial demagnetization.

[0097] Through combined adjustment, local mixed demagnetization fault is simulated.

[0098] 3. Data collection and analysis

[0099] The torque sensor and magnetic powder brake are activated to obtain the torque, output voltage and current data of the motor under various load conditions. Combined with the feedback data of the motor load, the comprehensive impact of the mixed demagnetization mode on the electromagnetic characteristics and output performance of the motor is analyzed. The experimental results show that the impact of local mixed demagnetization on motor performance is more complex, resulting in nonlinear fluctuations in output torque and instability in operation.

[0100] These two embodiments verify the test platform's ability to flexibly simulate different demagnetization modes and its practicality in the study of permanent magnet motor demagnetization faults.

[0101] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any modifications, equivalent substitutions and improvements made by any technician familiar with the technical field within the technical scope disclosed by the present invention and within the spirit and principle of the present invention should be covered by the protection scope of the present invention.

Claims

1. A permanent magnet motor test platform with adjustable demagnetization fault mode, characterized in that: The platform comprises a platform base (1), a guide rail (2), an electric screw module (3) for adjusting the position of the rotor of the motor to be tested, a bearing support seat (4), a motor shaft (5), the motor to be tested (6), a coupling (7), a torque sensor (8), a torque sensor base (9), a motor (10) or a magnetic powder brake for simulating the load of the motor to be tested, a motor base (11), and a slider (12); wherein the electric screw module (3) drives the stator of the motor to be tested to move axially via a screw nut (16).

2. The permanent magnet motor test platform with adjustable demagnetization fault mode according to claim 1, characterized in that: The electric screw module (3) comprises a ball screw motor (13), a screw fixing seat (14), a nut connecting seat (15), a screw nut (16), a screw (17) and a screw support seat (18); the ball screw motor (13) drives the screw (17) to rotate, driving the screw nut (16) to move along the spiral path of the screw (17), so as to achieve axial displacement of the motor under test.

3. The permanent magnet motor test platform with adjustable demagnetization fault mode according to claim 1, characterized in that: The motor (6) under test comprises a front end cover (20), a bearing seat (21), a sleeve (22) for supporting the bearing to move in radial and axial degrees of freedom, a first rotor fixing member (23), a rotor core module (24), a second rotor fixing member (26), a stator core and winding (27), a machine base (28) and a rear end cover (29).

4. The permanent magnet motor test platform with adjustable demagnetization fault mode according to claim 3, characterized in that: The rotor core module (24) adopts a dovetail groove guide rail structure, and is composed of an iron core (30) with a dovetail groove notch and a dovetail iron block assembly (31). The dovetail iron block assembly (31) is embedded in the notch to facilitate the insertion and removal of the dovetail iron block (32) and the attached permanent magnet (25), thereby realizing the replacement of the permanent magnet.

5. The permanent magnet motor test platform with adjustable demagnetization fault mode according to claim 1, characterized in that: The dimensions of the permanent magnet (25) in the X, Y and Z directions are all adjustable to simulate different local demagnetization faults; in the X direction, the thickness of the permanent magnet is adjusted to simulate radial demagnetization; in the Y direction, the arc length of the permanent magnet is adjusted to simulate tangential demagnetization; in the Z direction, the axial length of the permanent magnet is adjusted to simulate axial demagnetization.

6. The permanent magnet motor test platform with adjustable demagnetization fault mode according to claim 1, characterized in that: The axially adjustable length of the motor (6) under test is twice the length of the rotor, and the lengths of the motor shaft (5) and the base (28) are both more than twice the lengths of corresponding parts of a motor of the same model, so as to ensure that when the stator moves in the axial direction, uniform demagnetization fault simulation can be achieved and the adjustment of the demagnetization fault mode is facilitated.

7. A simulation test method for permanent magnet motor demagnetization fault, characterized in that: The method comprises the following steps: a) installing the motor under test (6) on a permanent magnet motor test platform with adjustable demagnetization fault mode, and adjusting the stator position of the motor under test by means of an electric screw module (3) so that the stator moves axially to a predetermined test position; b) starting a torque sensor (8) and a motor (10) or a magnetic powder brake simulating a load in a test platform to obtain torque data of the motor under different load conditions; c) driving the lead screw nut (16) to move by means of the electric lead screw module (3), thereby adjusting the position of the stator of the motor under test in the axial direction, and simulating different uniform demagnetization faults.

8. The permanent magnet motor demagnetization fault simulation test method according to claim 7, characterized in that: The method further comprises the following steps: d) According to the demagnetization experimental research requirements of the motor under test, the dovetail iron block assembly (31) in the rotor core module (24) is pulled out or inserted, and the shape and size of (25) on the dovetail iron block assembly at different positions are adjusted to simulate different demagnetization modes, so as to test the working performance of the motor under different demagnetization conditions.

9. The permanent magnet motor demagnetization fault simulation test method according to claim 7, characterized in that: The adjustment of the shape and size of the permanent magnet on the dovetail iron block assembly in step d includes adjusting the size of the permanent magnet (25) in the X, Y, and Z directions, specifically including: Adjust the thickness of the permanent magnet in the X direction to simulate radial demagnetization; Adjust the arc length of the permanent magnet in the Y direction to simulate tangential demagnetization; The axial length of the permanent magnet in the Z direction is adjusted to simulate axial demagnetization; According to actual needs, select the combined adjustment of the three directions of X, Y and Z to achieve complex local demagnetization fault simulation.

10. The permanent magnet motor demagnetization fault simulation test method according to claim 7, characterized in that: The method further comprises the following steps: e) using a torque sensor (8) to collect torque data under different demagnetization conditions, and combining it with feedback data from a load motor (10) or a magnetic powder brake, analyzing the effects of different demagnetization modes on motor output performance, and obtaining the effects of demagnetization faults on the efficiency and stability of the permanent magnet motor.

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