Temperature detection method and system of permanent magnet motor rotor and motor rotor structure

Abstract

The invention relates to the technical field of data processing of permanent magnet motor rotors, and particularly discloses a temperature detection method and system of a permanent magnet motor rotor and a motor rotor structure, and the method comprises the steps of permanent magnet motor operation state detection, permanent magnet motor environment monitoring, permanent magnet motor rotor temperature detection and abnormal temperature early warning. The operation stability index of the permanent magnet motor is obtained by acquiring and analyzing the operation data of the permanent magnet motor, the motor is ensured to operate in a stable and safe state, and the environmental condition of the motor can be known more comprehensively by acquiring and analyzing the environmental data of the permanent magnet motor. Important reference is provided for subsequent temperature characteristic data analysis and safety index calculation, the temperature characteristic data of the rotor are obtained, the temperature change of the rotor is detected, and the temperature characteristic data of the permanent magnet motor rotor and the reference rotor temperature characteristic data are comprehensively analyzed, so that the temperature safety of the rotor is quantitatively evaluated, and the safety of the rotor is improved. And the motor is ensured to operate in a safe temperature range.

Description

Technical Field

[0001] The present invention relates to the technical field of data processing of a permanent magnet motor rotor, and in particular to a temperature detection method and system for a permanent magnet motor rotor and a motor rotor structure. Background Art

[0002] Currently, in the field of permanent magnet motors, temperature detection is an important part of ensuring the normal operation of the motor, extending its service life and improving its safety. Permanent magnet motor rotors are widely used in electric vehicles, wind power generation, industrial drives and other fields due to their high energy density and high efficiency. However, permanent magnets themselves are sensitive to temperature. Excessive temperature will cause magnetic degradation, which will affect the performance of the motor and may even cause damage to the motor. Therefore, accurately detecting the temperature of the permanent magnet motor rotor is an important means to ensure the safe and efficient operation of the motor.

[0003] For example, the invention patent with announcement number CN105844030B specifically announces a method for online estimation of the rotor temperature of a permanent magnet synchronous motor. The software algorithm is used to estimate the rotor temperature of the permanent magnet synchronous motor without significantly increasing the hardware cost. The rotor temperature of the permanent magnet synchronous motor is monitored in real time by detecting variables such as the three-phase current, line voltage, rotor position and speed, and stator temperature of the permanent magnet synchronous motor.

[0004] For example, the invention patent with announcement number CN117077456B announces a temperature compensation method for a permanent magnet synchronous motor for an electronic water pump, including the following steps: obtaining the resistance-temperature change curve and the inductance-temperature change curve of the electronic water pump; according to the resistance-temperature change curve and the inductance-temperature change curve of the electronic water pump, the proportional coefficient and the integral coefficient of the current loop current regulator are calculated according to the typical first-order system setting of the engineering method, and the rotor flux and the rotor position are calculated according to the voltage equation and the flux equation of the permanent magnet synchronous motor; according to the obtained proportional coefficient, integral coefficient, rotor flux and rotor position, the current loop regulator and the rotor position observer are adjusted according to the real-time temperature compensation.

[0005] However, in the process of implementing the technical solution of the invention in the embodiments of the present application, the present application found that the above technology has at least the following technical problems: In the existing permanent magnet motor rotor temperature detection method, the rotor temperature is often detected based on a single factor. A single factor is difficult to fully reflect the actual temperature change of the rotor, resulting in inaccurate detection of the permanent magnet motor rotor temperature and failure to timely discover the potential risk of abnormal permanent magnet motor rotor temperature. Summary of the invention

[0006] In view of the deficiencies in the prior art, the present invention provides a temperature detection method and system for a permanent magnet motor rotor and a motor rotor structure, which can effectively solve the problems involved in the above-mentioned background technology.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions: In a first aspect, the present invention provides a temperature detection method for a permanent magnet motor rotor, comprising: S1. Permanent magnet motor operation status detection: obtain and analyze the operation data of the permanent magnet motor, obtain the permanent magnet motor operation stability index, and compare it with the permanent magnet motor operation stability index limit value preset in the rotor detection database to obtain a comparison result, and finally determine whether it is necessary to issue an early warning prompt for the operation status of the permanent magnet motor based on the comparison result; S2. Permanent magnet motor environment monitoring: obtain the environmental data of the permanent magnet motor, and conduct a comprehensive analysis with the permanent magnet motor operation stability index to obtain the permanent magnet motor environmental impact index, match the permanent magnet motor environmental impact index with the reference rotor temperature characteristic data corresponding to each permanent magnet motor environmental impact index interval preset in the rotor detection database, and obtain the reference rotor temperature characteristic data corresponding to the permanent magnet motor in the current environment; S3. Temperature detection of the permanent magnet motor rotor: The temperature characteristics of the permanent magnet motor rotor are detected by the temperature detection component, thereby obtaining the temperature characteristic data of the permanent magnet motor rotor, and the temperature characteristic data of the permanent magnet motor rotor is comprehensively analyzed with the reference rotor temperature characteristic data to obtain the permanent magnet motor rotor temperature safety index; S4. Abnormal temperature warning: compare the permanent magnet motor rotor temperature safety index with the permanent magnet motor rotor temperature safety index threshold preset in the rotor detection database. If the permanent magnet motor rotor temperature safety index is less than the preset permanent magnet motor rotor temperature safety index threshold, a warning prompt is given for the temperature of the permanent magnet motor rotor.

[0008] As a further method, the operation stability index of the permanent magnet motor is specifically analyzed as follows: The average input power of the permanent magnet motor during the operation detection period is obtained by multiplying the average input current of the permanent magnet motor during the operation detection period by the average input voltage; The average output power of the permanent magnet motor during the operation detection period is obtained by multiplying the average output current of the permanent magnet motor during the operation detection period by the average output voltage; The average output power of the permanent magnet motor in the operation detection period is processed by ratio processing with the average input power to obtain the average efficiency of the permanent magnet motor in the operation detection period; The average magnetic flux of the permanent magnet motor during the operation detection period is obtained by multiplying the average electromagnetic induction intensity of the permanent magnet motor during the operation detection period by the average magnetic circuit area; The average efficiency, average speed, average torque and average magnetic flux of the permanent magnet motor during the operation detection period are comprehensively analyzed to obtain the permanent magnet motor operation stability index.

[0009] As a further method, the comparison result is used to determine whether an early warning is required for the operation status of the permanent magnet motor. The specific determination process is as follows: If the permanent magnet motor operation stability index is greater than or equal to the preset permanent magnet motor operation stability index limit value, the comparison result will be recorded as the first comparison result. Otherwise, if the permanent magnet motor operation stability index is less than the preset permanent magnet motor operation stability index limit value, the comparison result will be recorded as the second comparison result.

[0010] If the comparison result is the second comparison result, it is necessary to give an early warning prompt for the running state of the permanent magnet motor.

[0011] As a further method, the environmental impact index of the permanent magnet motor is specifically analyzed as follows: The average temperature, average humidity, average air flow speed, average dust particle concentration, average electromagnetic interference intensity and permanent magnet motor operation stability index of the environment in which the permanent magnet motor is located during the operation cycle are comprehensively analyzed to obtain the permanent magnet motor environmental impact index.

[0012] As a further method, the permanent magnet motor rotor temperature safety index, the specific analysis process is: The maximum temperature of the rotor of the permanent magnet motor during the operation cycle is processed with the average temperature of the environment to which the permanent magnet motor belongs during the operation cycle to obtain the temperature difference of the rotor of the permanent magnet motor during the operation cycle.

[0013] The maximum temperature, temperature difference, average heat capacity, average thermal resistance, average heat dissipation power of the permanent magnet motor rotor during the operation cycle, the allowable temperature of the permanent magnet motor rotor, the reference heat capacity, reference thermal resistance and the limit value of heat dissipation power are comprehensively analyzed to obtain the permanent magnet motor rotor temperature safety index. The specific analysis method is as follows: ; In the formula, is the permanent magnet motor rotor temperature safety index, e is the natural constant, is the maximum temperature of the rotor of the permanent magnet motor during its operation cycle, The allowable temperature of the permanent magnet motor rotor preset in the rotor detection database, is the temperature difference of the rotor of the permanent magnet motor during its operation cycle, The safety index corresponding to the temperature difference unit value preset in the rotor detection database, is the average heat capacity of the rotor of the permanent magnet motor during its operation cycle, The reference thermal capacity of the permanent magnet motor rotor preset in the rotor detection database, is the average thermal resistance of the rotor of the permanent magnet motor during its operation cycle, The reference thermal resistance of the permanent magnet motor rotor preset for the rotor detection database, is the average heat dissipation power of the rotor of the permanent magnet motor during its operation cycle, The heat dissipation power limit value of the permanent magnet motor rotor preset in the rotor detection database.

[0014] The second aspect of the present invention provides a temperature detection system for a permanent magnet motor rotor, comprising: a permanent magnet motor operating status detection module, used to acquire and analyze the operating data of the permanent magnet motor, obtain the permanent magnet motor operating stability index, and compare it with the permanent magnet motor operating stability index limit value preset in the rotor detection database to obtain a comparison result, and finally determine whether it is necessary to issue an early warning prompt for the operating status of the permanent magnet motor based on the comparison result.

[0015] The permanent magnet motor environment monitoring module is used to obtain the environmental data of the permanent magnet motor, and conduct a comprehensive analysis with the permanent magnet motor operation stability index to obtain the permanent magnet motor environmental impact index, and match the permanent magnet motor environmental impact index with the reference rotor temperature characteristic data corresponding to each permanent magnet motor environmental impact index interval preset in the rotor detection database to obtain the reference rotor temperature characteristic data corresponding to the permanent magnet motor in the current environment.

[0016] The temperature detection module of the permanent magnet motor rotor is used to detect the temperature characteristics of the permanent magnet motor rotor through the temperature detection component, thereby obtaining the temperature characteristic data of the permanent magnet motor rotor, and comprehensively analyzing the temperature characteristic data of the permanent magnet motor rotor with the reference rotor temperature characteristic data to obtain the permanent magnet motor rotor temperature safety index.

[0017] The abnormal temperature warning module is used to compare the permanent magnet motor rotor temperature safety index with the permanent magnet motor rotor temperature safety index threshold preset in the rotor detection database. If the permanent magnet motor rotor temperature safety index is less than the preset permanent magnet motor rotor temperature safety index threshold, an early warning prompt is issued for the temperature of the permanent magnet motor rotor.

[0018] The third aspect of the present invention provides a permanent magnet motor rotor structure, characterized in that it comprises: a rotor outer shaft, a motor rotor assembly is arranged outside the rotor outer shaft, characterized in that: the rotor outer shaft is arranged inside a rotor inner shaft that does not rotate with the rotor outer shaft, a temperature detection component for detecting the temperature characteristics of the permanent magnet motor rotor. A light source speed measurement component for detecting the average speed of the permanent magnet motor during the operation detection cycle.

[0019] Compared with the prior art, the embodiments of the present invention have at least the following advantages or beneficial effects: (1) The present invention obtains and analyzes the operation data of the permanent magnet motor to obtain the operation stability index of the permanent magnet motor, thereby ensuring that the motor operates in a stable and safe state. The present invention can timely detect abnormalities in the operation of the motor, provide a basis for subsequent early warning prompts and fault troubleshooting, and compare the data with the preset limit value of the permanent magnet motor operation stability index in the rotor detection database to accurately determine whether early warning measures need to be taken, so as to take measures in time to avoid faults and ensure the safe and stable operation of the motor. (2) By acquiring and analyzing the environmental data of the permanent magnet motor, the present invention can more comprehensively understand the environmental conditions of the motor and provide an important reference for subsequent temperature characteristic data analysis and safety index calculation; (3) The present invention obtains the temperature characteristic data of the permanent magnet motor rotor, which is the key basis for evaluating the temperature safety of the motor rotor. By obtaining the temperature characteristic data of the rotor, the temperature change of the rotor can be monitored, providing accurate data support for the subsequent calculation of the temperature safety index, and the temperature characteristic data of the permanent magnet motor rotor and the reference rotor temperature characteristic data are comprehensively analyzed to obtain the permanent magnet motor rotor temperature safety index, so as to quantitatively evaluate the temperature safety of the rotor. The temperature safety index can intuitively reflect the temperature state of the rotor, providing an important basis for subsequent early warning prompts and troubleshooting; (4) The present invention further quantitatively evaluates the temperature safety of the rotor by comparing the permanent magnet motor rotor temperature safety index with the permanent magnet motor rotor temperature safety index threshold value preset in the rotor detection database, thereby ensuring that the motor operates within a safe temperature range. If the permanent magnet motor rotor temperature safety index is less than the preset permanent magnet motor rotor temperature safety index threshold value, an early warning prompt is issued for the temperature of the permanent magnet motor rotor. The early warning prompt can promptly inform the operator of possible problems with the rotor temperature, so that measures can be taken in time to reduce the temperature or shut down the machine for inspection, thereby avoiding the occurrence or expansion of faults. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention is further described with the aid of the accompanying drawings, but the embodiments in the accompanying drawings do not constitute any limitation to the present invention. A person skilled in the art can obtain other accompanying drawings based on the following accompanying drawings without creative work. Figure 1 It is a schematic diagram of the method steps of the present invention; Figure 2 It is a schematic diagram of system module connection of the present invention; Figure 3 It is a schematic cross-sectional view of a motor of the present invention; Figure 4 It is a partial cross-sectional schematic diagram of the temperature detection assembly of the present invention; Figure 5 It is a schematic diagram of the three-dimensional structure of the inner shaft of the rotor of the present invention; Figure 6 It is a three-dimensional partial enlarged structural schematic diagram of the rotor inner shaft of the present invention (I); Figure 7 It is a three-dimensional partial enlarged structural schematic diagram (II) of the rotor inner shaft of the present invention; Figure 8 It is a schematic diagram of the three-dimensional structure of the wiring harness disk of the present invention (I); Fig. 9 It is a schematic diagram of the three-dimensional structure (II) of the wiring harness disk of the present invention; Fig.10 It is a schematic diagram of the overall three-dimensional structure of the rotor structure of the present invention placed in an electronic state; Fig.11 It is a schematic diagram of the three-dimensional structure of the rotor structure of the present invention.

[0021] Figure numerals: 1. rotor outer shaft; 2. motor rotor assembly; 3. rotor inner shaft; 4. bearing; 5. inner shaft limit plate; 6. guide rail stator pole; 7. harness disk; 8. slide groove; 9. pole drive block; 10. connecting rod; 11. thermal sensor; 12. fixed code disk; 13. code disk light hole; 14. signal light source; 15. photosensitive signal receiver. DETAILED DESCRIPTION

[0022] 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 only part of the embodiments of the present invention, rather than all the embodiments. 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.

[0023] Reference Figure 1 As shown, the first aspect of the present invention provides a temperature detection method for a permanent magnet motor rotor, comprising: S1. Permanent magnet motor operating status detection: acquiring and analyzing the operating data of the permanent magnet motor, obtaining the permanent magnet motor operating stability index, and comparing it with the permanent magnet motor operating stability index limit value preset in the rotor detection database to obtain a comparison result, and finally judging whether it is necessary to issue an early warning prompt for the operating status of the permanent magnet motor based on the comparison result.

[0024] S2. Permanent magnet motor environmental monitoring: obtain the environmental data of the permanent magnet motor, and conduct a comprehensive analysis with the permanent magnet motor operation stability index to obtain the permanent magnet motor environmental impact index, match the permanent magnet motor environmental impact index with the reference rotor temperature characteristic data corresponding to each permanent magnet motor environmental impact index interval preset in the rotor detection database, and obtain the reference rotor temperature characteristic data corresponding to the permanent magnet motor in the current environment.

[0025] S3. Temperature detection of the permanent magnet motor rotor: The temperature characteristics of the permanent magnet motor rotor are detected by the temperature detection component to obtain the temperature characteristic data of the permanent magnet motor rotor. The temperature characteristic data of the permanent magnet motor rotor and the reference rotor temperature characteristic data are comprehensively analyzed to obtain the permanent magnet motor rotor temperature safety index.

[0026] S4. Abnormal temperature warning: compare the permanent magnet motor rotor temperature safety index with the permanent magnet motor rotor temperature safety index threshold preset in the rotor detection database. If the permanent magnet motor rotor temperature safety index is less than the preset permanent magnet motor rotor temperature safety index threshold, a warning prompt is given for the temperature of the permanent magnet motor rotor.

[0027] Specifically, the operating data of the permanent magnet motor includes an average input current, an average input voltage, an average output current, an average output voltage, an average torque, an average electromagnetic induction intensity and an average magnetic circuit area of ​​the permanent magnet motor during an operating detection period.

[0028] In this embodiment, the operation detection cycle refers to the time interval for detecting the permanent magnet motor, and this cycle is randomly set to ensure that the permanent magnet motor can maintain its stable performance, safety and reliability during operation.

[0029] The permanent magnet motor is detected by the light source speed measuring component during the operation detection cycle, thereby obtaining the average speed of the permanent magnet motor during the operation detection cycle.

[0030] In this embodiment, there is indeed a mutual influence relationship between the average input current, average input voltage, average output current, average output voltage, average torque, average electromagnetic induction intensity, average magnetic circuit area and average speed of the permanent magnet motor during the operation detection cycle. There is a direct relationship between the average input current and the average input voltage. When the average input voltage increases, the average input current will also increase accordingly. In the permanent magnet motor, current is the key factor in generating torque. When the current increases, the torque generated by the interaction between the current and the magnetic field will also increase. Therefore, an increase in the average input current will lead to an increase in the average torque. When the motor input voltage increases, the rotating magnetic field generated by the rotor is enhanced, thereby driving the rotor to rotate at a higher speed. Therefore, an increase in the average input voltage will lead to an increase in the average speed. Under a certain power, an increase in torque of the permanent magnet motor will lead to an increase in speed. There is a direct relationship between the average electromagnetic induction intensity and the average magnetic circuit area. The electromagnetic induction intensity is a physical quantity that describes the strength of the magnetic field, and the magnetic circuit area is the cross-sectional area through which the magnetic field passes. When the magnetic circuit design remains unchanged, an increase in the average electromagnetic induction intensity will lead to an increase in the average magnetic circuit area.

[0031] Specifically, the operation stability index of the permanent magnet motor is analyzed in the following steps: The average input power of the permanent magnet motor during the operation detection period is obtained by multiplying the average input current of the permanent magnet motor during the operation detection period by the average input voltage.

[0032] The average output power of the permanent magnet motor during the operation detection period is obtained by multiplying the average output current of the permanent magnet motor during the operation detection period by the average output voltage.

[0033] The average output power of the permanent magnet motor in the operation detection period is processed by ratio processing with the average input power to obtain the average efficiency of the permanent magnet motor in the operation detection period.

[0034] The average magnetic flux of the permanent magnet motor during the operation detection period is obtained by multiplying the average electromagnetic induction intensity of the permanent magnet motor during the operation detection period by the average magnetic circuit area.

[0035] The average efficiency, average speed, average torque and average magnetic flux of the permanent magnet motor during the operation detection period are comprehensively analyzed to obtain the operation stability index of the permanent magnet motor. The specific analysis method is as follows: ; In the formula, is the operating stability index of the permanent magnet motor, e is the natural constant, is the average efficiency of the permanent magnet motor during the running detection period, The operation stability index corresponding to the average efficiency unit value preset in the rotor detection database, is the average speed of the permanent magnet motor during the running detection period, The reference speed preset for the rotor detection database, is the average torque of the permanent magnet motor during the running detection cycle, The reference torque preset for the rotor detection database, is the average magnetic flux of the permanent magnet motor during the running detection cycle, Reference flux preset for the rotor detection database.

[0036] It needs to be explained that the average efficiency of the permanent magnet motor during the operation detection cycle refers to the ratio of the average output power to the average input power, where the average output power is the product of the average input current and the average input voltage, and the average input power is the product of the average output current and the average output voltage. The average input current and the average output current of the permanent magnet motor during the operation detection cycle are directly measured by the current sensor. The input current and the input current of the permanent magnet motor during the operation detection cycle are obtained by calculating the average value during the operation detection cycle. The average input voltage and the average input voltage are obtained by using a voltage sensor to monitor the input voltage and output voltage of the permanent magnet motor and taking their average values ​​within an operation detection cycle. The average speed refers to the average speed of the rotor rotation of the permanent magnet motor during its operation detection cycle, which is detected by the light source speed measurement component. The average torque refers to the average rotational torque generated by the permanent magnet motor during its operation detection cycle, which is obtained by the torque sensor, and then the average value of the torque during the operation detection cycle is calculated to obtain the average torque. The average magnetic flux refers to the average electromagnetic induction intensity of the permanent magnet motor during its operation detection cycle. and the product of the average magnetic circuit area, wherein the electromagnetic induction intensity can be measured by using a Hall sensor, multiple measurements are performed within the operation detection cycle, and the average value is calculated, thereby obtaining the average electromagnetic induction intensity, the average magnetic circuit area is related to the design and structure of the motor, and the magnetic circuit area can be obtained by viewing the design parameters of the motor, the preset reference speed refers to a standard speed value preset in the rotor detection database, which is used to compare with the actual measured speed, the preset reference torque refers to a standard torque value preset in the rotor detection database, which is used to compare with the actual measured torque, the preset reference flux refers to a standard flux value preset in the rotor detection database, which is used to compare with the actual measured flux, the operation stability index corresponding to the preset average efficiency unit value, which indicates the degree of influence of the average efficiency unit value on the operation stability index of the permanent magnet motor, the rotor detection database stores the corresponding relationship between the average efficiency and its corresponding operation stability index, for example, the average efficiency is input into the rotor detection database, and the rotor detection database can match the operation stability index corresponding to the average efficiency unit value, and its value range in this example is (0, 1).

[0037] In this embodiment, a smaller average efficiency means that the energy conversion efficiency of the permanent magnet motor is lower during operation, and more energy is converted into heat or other forms of loss, which not only increases energy consumption but also causes motor overheating; when the average speed is faster or slower, that is, when the deviation from the preset reference speed is large, the slow average speed may cause the output power of the permanent magnet motor to decrease and fail to meet the working requirements. In addition, the high speed may cause the vibration and noise of the motor to increase, accelerate the wear of mechanical parts, and further reduce the stability and reliability of the motor; when the average torque is larger or smaller, that is, when the deviation from the preset reference torque is large, it may mean that the load fluctuation of the permanent magnet motor is large, or the electric The design parameters of the motor do not match the actual working conditions. Excessive torque may cause motor overload and accelerate the wear and fatigue of mechanical parts; while too small torque may not meet the working requirements, resulting in low motor efficiency. The average magnetic flux is large or small, that is, when the deviation from the preset reference magnetic flux is large, it indicates that the magnetic field distribution of the permanent magnet motor is uneven or the magnetic field strength has changed. The uneven distribution of the magnetic field will lead to an imbalance in the electromagnetic force of the motor, causing increased vibration and noise, and will also affect the output torque and efficiency of the motor. Therefore, through a detailed analysis of the parameters in the permanent magnet motor operation stability index, abnormal conditions in the motor operation can be discovered, and the motor's operating efficiency and stability can be improved.

[0038] Furthermore, the process of judging whether it is necessary to give an early warning for the operation state of the permanent magnet motor according to the comparison result is as follows: If the permanent magnet motor operation stability index is greater than or equal to the preset permanent magnet motor operation stability index limit value, the comparison result will be recorded as the first comparison result. Otherwise, if the permanent magnet motor operation stability index is less than the preset permanent magnet motor operation stability index limit value, the comparison result will be recorded as the second comparison result.

[0039] In this embodiment, the permanent magnet motor operation stability index is compared with the permanent magnet motor operation stability index limit value preset in the rotor detection database. If the permanent magnet motor operation stability index is greater than or equal to the preset permanent magnet motor operation stability index limit value, it means that the current operating state of the permanent magnet motor is stable, and its performance meets or exceeds expectations. Therefore, this comparison result is recorded as the "first comparison result". On the contrary, if the permanent magnet motor operation stability index is less than the preset permanent magnet motor operation stability index limit value, this means that the current operating state of the permanent magnet motor is unstable, and there may be some kind of fault or performance degradation. Therefore, this comparison result is recorded as the "second comparison result", which usually indicates that the permanent magnet motor needs further inspection or maintenance.

[0040] If the comparison result is the second comparison result, it is necessary to give an early warning prompt for the running state of the permanent magnet motor.

[0041] In this embodiment, the operation status of the permanent magnet motor can be warned by displaying a clear alarm message on the control panel, such as "the permanent magnet motor is unstable, please check immediately". After receiving the warning, the staff should immediately stop the machine and check the various parameters and states of the permanent magnet motor, such as temperature, vibration, current, etc., to determine the specific cause of the problem. According to the inspection results, the fault sources that may cause the permanent magnet motor to operate unstable are checked one by one, such as sensor failure, power supply fluctuation, excessive load, etc. Once the fault source is determined, the damaged parts should be repaired or replaced immediately to ensure the normal operation of the permanent magnet motor. After repairing or replacing the parts, the permanent magnet motor needs to be recalibrated and adjusted to ensure that its performance is restored to the best state, and the permanent magnet motor operation stability index is analyzed again. After the above measures, the analysis of the permanent magnet motor operation stability index reaches or exceeds the preset permanent magnet motor operation stability index limit value, which is recorded as the first comparison result, which indicates that the operation status of the permanent magnet motor has been stabilized and the performance is in line with expectations or better than expectations. After the permanent magnet motor is stable, in order to further understand the impact of the operating environment of the permanent magnet motor on its performance, environmental data can be extracted.

[0042] Specifically, the environmental data of the permanent magnet motor includes temperature, humidity, air flow velocity, dust particle concentration and electromagnetic interference intensity of the environment of the permanent magnet motor at each environmental detection time point during the operation cycle.

[0043] It should be explained that the temperature of the environment to which the above-mentioned permanent magnet motor belongs at each environmental detection time point during the operation cycle is obtained by the environmental temperature sensor by recording the temperature data at each environmental detection time point; the humidity is obtained by monitoring the humidity data at each environmental detection time point during the operation cycle by the environmental humidity sensor, and the air flow rate is obtained by measuring the air flow data at each environmental detection time point during the operation cycle by the wind speed sensor; the dust particle concentration can be measured by a dust particle counter to measure the dust particle quantity data at each environmental detection time point during the operation cycle, and the number of dust particles in this case is actually another quantitative description of the dust particle concentration; the electromagnetic interference intensity can be measured by an electromagnetic field measuring instrument. The electromagnetic field intensity data at each environmental detection time point, in this embodiment, the operation cycle refers to the time period in which the permanent magnet motor continuously runs in the actual working environment, which is usually randomly arranged according to the actual operating state of the motor, and each environmental detection time point refers to a specific time point set for monitoring and recording the environmental conditions of the permanent magnet motor, and these time points are usually determined according to the operating conditions of the motor and the law of environmental changes to ensure that the environmental conditions of the motor during operation can be fully and accurately reflected.

[0044] The temperature, humidity, air flow velocity, dust particle concentration and electromagnetic interference intensity of the environment to which the permanent magnet motor belongs at each environmental detection time point during the operation cycle are summed up respectively to obtain the total temperature, total humidity, total air flow velocity, total dust particle concentration and total electromagnetic interference intensity of the environment to which the permanent magnet motor belongs during the operation cycle.

[0045] Get the number of environmental detections of the environment to which the permanent magnet motor belongs during its operation cycle.

[0046] It should be explained that the number of environmental detections of the environment to which the above-mentioned permanent magnet motor belongs during the operation cycle is obtained by referring to the environmental detection report of the permanent magnet motor during the operation cycle.

[0047] The total temperature, total humidity, total air flow speed, total dust particle concentration and total electromagnetic interference intensity of the environment to which the permanent magnet motor belongs during the operating cycle are divided by the number of environmental detections of the environment to which the permanent magnet motor belongs during the operating cycle, and the average temperature, average humidity, average air flow speed, average dust particle concentration and average electromagnetic interference intensity of the environment to which the permanent magnet motor belongs during the operating cycle are obtained.

[0048] In this embodiment, there are certain mutual influences and relationships between parameters such as the average temperature, average humidity, average air flow speed, average dust particle concentration, and average electromagnetic interference intensity in the environment of the permanent magnet motor. Within a certain range, as the temperature rises, the water vapor content in the air may increase, thereby causing the humidity to rise. The air flow can take away the heat on the surface of the motor, which helps to reduce the temperature of the motor. Therefore, an increase in the air flow speed may reduce the average temperature of the motor to a certain extent. However, if the air flow speed is too fast, it will take away too much heat, resulting in uneven or too low temperature distribution inside the motor, affecting the normal operation of the motor. The high temperature environment may accelerate the deposition and adhesion of dust particles on the surface of the motor. The increase in electromagnetic interference will aggravate the temperature rise problem of the motor.

[0049] Specifically, the environmental impact index of the permanent magnet motor is analyzed in the following steps: The average temperature, average humidity, average air flow speed, average dust particle concentration, average electromagnetic interference intensity and permanent magnet motor operation stability index of the environment of the permanent magnet motor during the operation cycle are comprehensively analyzed to obtain the permanent magnet motor environmental impact index. The specific analysis method is as follows: ; In the formula, is the environmental impact index of permanent magnet motor, e is the natural constant, is the operating stability index of the permanent magnet motor, is the average temperature of the environment of the permanent magnet motor during the operation cycle, The reference temperature preset for the rotor detection database, is the average humidity of the environment of the permanent magnet motor during its operation cycle, Reference humidity preset for the rotor detection database, is the average concentration of dust particles in the environment of the permanent magnet motor during its operation cycle, The environmental impact index corresponding to the unit value of the average dust particle concentration preset in the rotor detection database, is the average electromagnetic interference intensity of the environment of the permanent magnet motor during the operation cycle, The environmental impact index corresponding to the unit value of the average electromagnetic interference intensity preset in the rotor detection database, is the average air flow velocity of the permanent magnet motor's environment during the operation cycle, The air flow reference speed preset for the rotor detection database, The environmental impact index corresponding to the permanent magnet motor operation stability index preset in the rotor detection database.

[0050] It should be explained that the average temperature of the environment to which the above-mentioned permanent magnet motor belongs during the operation cycle refers to the average temperature of the environment to which the permanent magnet motor belongs during its operation detection cycle, which is obtained by the ambient temperature sensor by recording the temperature data during the operation cycle and calculating its average value. The average humidity refers to the average humidity of the environment to which the permanent magnet motor belongs during its operation detection cycle, which is obtained by monitoring the humidity data during the operation cycle through the ambient humidity sensor and calculating its average value. The average concentration of dust particles refers to the average concentration of dust particles in the environment to which the permanent magnet motor belongs during its operation detection cycle, which is obtained by monitoring the humidity data during the operation cycle through the ambient humidity sensor and calculating its average value. The average electromagnetic interference intensity refers to the concentration of dust particles in the environment to which the permanent magnet motor belongs during its operation detection cycle. The average intensity of electromagnetic interference can be obtained by measuring the electromagnetic field intensity data within the operation cycle through an electromagnetic field measuring instrument, and calculating its average value to obtain the average electromagnetic interference intensity. The average air flow speed refers to the average speed of air flow in the environment where the permanent magnet motor is located during its operation detection cycle. The air flow data within the operation cycle is measured by a wind speed sensor and the average value is calculated to obtain the average air flow speed. The preset reference temperature refers to a reference temperature value preset in the rotor detection database in order to accurately detect the rotor. The preset reference humidity refers to a reference humidity value preset in the rotor detection database in order to accurately detect the rotor. The preset air flow reference speed refers to a reference air flow speed value preset in the rotor detection database in order to accurately detect the rotor.

[0051] The environmental impact index corresponding to the unit value of the average dust particle concentration preset in the rotor detection database is an index that represents the degree of influence of the unit value of the average dust particle concentration on the environmental impact index of the permanent magnet motor. The rotor detection database stores the corresponding relationship between the average dust particle concentration and its corresponding environmental impact index. For example, when the average dust particle concentration is input into the rotor detection database, the rotor detection database can match the environmental impact index corresponding to the unit value of the average dust particle concentration. At the same time, in this example, its value range is (0, 1).

[0052] The environmental impact index corresponding to the unit value of the electromagnetic average interference intensity preset in the rotor detection database represents the index of the degree of influence of the unit value of the electromagnetic average interference intensity on the environmental impact index of the permanent magnet motor. The rotor detection database stores the corresponding relationship between the electromagnetic average interference intensity and its corresponding environmental impact index. For example, the electromagnetic average interference intensity is input into the rotor detection database, and the rotor detection database can match the environmental impact index corresponding to the unit value of the electromagnetic average interference intensity. At the same time, in this example, its value range is (0, 1).

[0053] The environmental impact index corresponding to the permanent magnet motor operation stability index preset in the rotor detection database is an index representing the degree of influence of the permanent magnet motor operation stability index on the permanent magnet motor environmental impact index. The rotor detection database stores the corresponding relationship between the permanent magnet motor operation stability index and its corresponding environmental impact index. For example, the permanent magnet motor operation stability index is input into the rotor detection database, and the rotor detection database can match the environmental impact index corresponding to the permanent magnet motor operation stability index. At the same time, in this example, its value range is (0, 1).

[0054] In this embodiment, when the average temperature is higher or lower, that is, when the degree of deviation from the preset reference temperature is large, the temperature that is too high or too low may have a negative impact on the performance of the permanent magnet motor. High temperature will cause thermal expansion of the internal components of the motor, increase mechanical stress, accelerate the aging of the insulating material, and even cause overheating protection and shutdown. Low temperature may cause the lubricant to solidify, increase the wear of mechanical components, and reduce the starting performance and efficiency of the motor; when the average humidity is higher or lower, that is, when the degree of deviation from the preset reference humidity is large, in a high humidity environment, the permanent magnet motor may be affected by corrosion and condensation, resulting in a decrease in insulation performance and an increased risk of electrical failure. At the same time, excessive humidity may also cause mildew and bacterial growth inside the motor, posing a threat to the long-term operation stability of the motor; a larger average concentration of dust particles will adhere to the heat sink and fan of the permanent magnet motor, hindering the dissipation of heat, causing the motor temperature to rise. Dust may also cause poor electrical contact and short circuit problems, increasing the risk of electrical failure; a larger average concentration of dust particles will adhere to the heat sink and fan of the permanent magnet motor, hindering the dissipation of heat, causing the motor temperature to rise. Dust may also cause poor electrical contact and short circuit problems, increasing the risk of electrical failure; The average electromagnetic interference intensity will affect the operation of the control system and sensors of the permanent magnet motor, resulting in signal distortion, malfunction or failure; when the average air flow speed is large or small, that is, when the degree of deviation from the preset air flow reference speed is large, the air flow speed is too fast, which may cause uneven heat dissipation inside the motor and increase the wear and vibration of mechanical parts. At the same time, too fast airflow may also cause dust particles to fly and increase the pollution inside the motor, while too slow air flow speed may cause poor heat dissipation of the motor and increase the temperature; a smaller permanent magnet motor operation stability index means that the motor may have large fluctuations and unstable factors during operation, such as speed fluctuations, torque instability, etc., which will affect the performance and efficiency of the motor. A smaller permanent magnet motor operation stability index will have a significant negative impact on the permanent magnet motor environmental impact index; therefore, by conducting a detailed analysis of the parameters in the permanent magnet motor environmental impact index, the environmental factors that affect the stable operation of the permanent magnet motor can be discovered in time, and the damage caused to the permanent magnet motor by environmental factors can be reduced.

[0055] Furthermore, the temperature characteristic data of the permanent magnet motor rotor specifically include the maximum temperature, average heat capacity, average thermal resistance and average heat dissipation power of the rotor during the operation cycle of the permanent magnet motor.

[0056] In this embodiment, there is a complex mutual influence relationship between the maximum temperature, average heat capacity, average thermal resistance and average heat dissipation power of the permanent magnet motor rotor. The larger the average thermal resistance, the greater the resistance to heat transfer from the inside of the rotor to the outside, causing heat accumulation inside the rotor, thereby increasing the maximum temperature. If the average thermal resistance is large, heat transfer is hindered, the heat dissipation capacity of the rotor will decrease, resulting in a decrease in the average heat dissipation power. When the average heat capacity of the rotor is large, it means that the temperature rise of the rotor is smaller after absorbing the same amount of heat, so the maximum temperature may be relatively low. Conversely, if the average heat capacity is small, the temperature of the rotor will rise rapidly after absorbing heat, resulting in a higher maximum temperature.

[0057] The reference rotor temperature characteristic data corresponding to the permanent magnet motor in the current environment specifically includes the allowable temperature, reference thermal capacity, reference thermal resistance and heat dissipation power limit value of the permanent magnet motor rotor.

[0058] It should be explained that the reference rotor temperature characteristic data corresponding to the permanent magnet motor in the current environment is obtained by matching the permanent magnet motor environmental impact index with the reference rotor temperature characteristic data corresponding to each permanent magnet motor environmental impact index interval preset in the rotor detection database. The specific matching process is: It should be explained that the above-mentioned matching of the permanent magnet motor environmental impact index with the reference rotor temperature characteristic data corresponding to each permanent magnet motor environmental impact index interval preset in the rotor detection database obtains the reference rotor temperature characteristic data corresponding to the permanent magnet motor in the current environment.

[0059] In a specific embodiment, the environmental impact index of the permanent magnet motor is 2.5, and the environmental impact index interval of each permanent magnet motor stored in the rotor detection database is [2, 3]. Then the reference rotor temperature characteristic data corresponding to the environmental impact index interval of the permanent magnet motor is [2, 3] are: the allowable temperature of the permanent magnet motor rotor is 120 degrees Celsius, the reference heat capacity is 5000 joules, the reference thermal resistance is 0.5 Kelvin per watt, and the heat dissipation power limit value is 300 watts.

[0060] Specifically, the permanent magnet motor rotor temperature safety index has a specific analysis process as follows: The maximum temperature of the rotor of the permanent magnet motor during the operation cycle is processed with the average temperature of the environment to which the permanent magnet motor belongs during the operation cycle to obtain the temperature difference of the rotor of the permanent magnet motor during the operation cycle.

[0061] The maximum temperature, temperature difference, average heat capacity, average thermal resistance, average heat dissipation power of the permanent magnet motor rotor during the operation cycle, the allowable temperature of the permanent magnet motor rotor, the reference heat capacity, reference thermal resistance and the limit value of heat dissipation power are comprehensively analyzed to obtain the permanent magnet motor rotor temperature safety index. The specific analysis method is as follows: ; In the formula, is the permanent magnet motor rotor temperature safety index, e is the natural constant, is the maximum temperature of the rotor of the permanent magnet motor during its operation cycle, The allowable temperature of the permanent magnet motor rotor preset in the rotor detection database, is the temperature difference of the rotor of the permanent magnet motor during its operation cycle, The safety index corresponding to the temperature difference unit value preset in the rotor detection database, is the average heat capacity of the rotor of the permanent magnet motor during its operation cycle, The reference thermal capacity of the permanent magnet motor rotor preset in the rotor detection database, is the average thermal resistance of the rotor of the permanent magnet motor during its operation cycle, The reference thermal resistance of the permanent magnet motor rotor preset for the rotor detection database, is the average heat dissipation power of the rotor of the permanent magnet motor during its operation cycle, The heat dissipation power limit value of the permanent magnet motor rotor preset in the rotor detection database.

[0062] It needs to be explained that the maximum temperature of the rotor of the above-mentioned permanent magnet motor during the operating cycle refers to the maximum temperature value that the rotor can reach during the normal operating cycle of the permanent magnet motor, the temperature difference of the rotor refers to the difference between the maximum temperature of the rotor of the permanent magnet motor during the operating cycle and the average temperature of the environment to which the permanent magnet motor belongs during the operating cycle, the average heat capacity of the rotor of the permanent magnet motor during the operating cycle refers to the average heat that the rotor can absorb or release under unit temperature change during the operating cycle of the permanent magnet motor, the average thermal resistance of the rotor of the permanent magnet motor during the operating cycle refers to the average resistance encountered by the rotor in the heat transfer process during the operating cycle of the permanent magnet motor, the average heat dissipation power of the rotor of the permanent magnet motor during the operating cycle refers to the average heat dissipated by the rotor of the permanent magnet motor during the operating cycle, the maximum temperature, average heat capacity, average thermal resistance and average heat dissipation power of the rotor of the permanent magnet motor during the operating cycle are all obtained through the temperature detection component, the temperature detection component uses a thermocouple sensor to directly measure the temperature signal of the rotor, and converts the temperature signal into an electrical signal (such as voltage, current or resistance value), and the data processing unit receives these electrical signals , and amplify, filter and A / D convert and combine with the data processing unit and algorithm to amplify, filter, convert and estimate, and finally obtain the temperature characteristic data of the permanent magnet motor rotor; the reference heat capacity of the permanent magnet motor rotor preset in the rotor detection database refers to the reference heat capacity value preset in the rotor detection database for evaluating the thermal stability of the permanent magnet motor rotor, the reference thermal resistance of the permanent magnet motor rotor preset in the rotor detection database refers to the reference thermal resistance value preset in the rotor detection database for evaluating the heat dissipation performance of the permanent magnet motor rotor, the preset heat dissipation power limit value of the permanent magnet motor rotor refers to the minimum value of the heat dissipation power preset in the rotor detection database for evaluating the heat dissipation performance of the permanent magnet motor rotor, the preset safety index corresponding to the temperature difference unit value, represents the index of the influence of the temperature difference unit value on the temperature safety index of the permanent magnet motor rotor, the rotor detection database stores the corresponding relationship between the temperature difference and its corresponding safety index, for example, the temperature difference is input into the rotor detection database, and the rotor detection database can match the corresponding safety index corresponding to the temperature difference unit value, and its value range in this example is (0, 1).

[0063] In this embodiment, when the maximum temperature of the rotor is high, even higher than the preset allowable temperature of the permanent magnet motor rotor, the permanent magnet material will lose part of its magnetism due to the high temperature, resulting in a decrease in motor performance; when the average heat capacity of the rotor is small or large, that is, when the degree of deviation from the preset reference heat capacity of the permanent magnet motor rotor is large, the small average heat capacity means that the rotor has a weaker ability to absorb heat, which may cause heat to accumulate inside the rotor, increasing the risk of temperature rise. On the contrary, an excessively large average heat capacity may mean that the rotor material is too thick, which is not conducive to the rapid transfer and dissipation of heat, and may also affect temperature control. Both situations will deteriorate the rotor temperature safety index; when the average thermal resistance of the rotor is large or small, that is, when the degree of deviation from the preset reference thermal resistance of the permanent magnet motor rotor is large, the large average thermal resistance will hinder the transfer of heat from the rotor to the external environment, resulting in a decrease in rotor temperature. The temperature rises, and although the average thermal resistance is too small, it is conducive to heat transfer, but it may mean that the heat exchange between the rotor and the external environment is too frequent and intense, increasing the risk of temperature fluctuations, which is also not conducive to temperature stability; when the average heat dissipation power of the smaller rotor is even less than the preset heat dissipation power limit value of the permanent magnet motor rotor, the smaller average heat dissipation power means that the rotor has insufficient heat dissipation capacity and cannot dissipate the internal heat to the external environment in time, which will cause the rotor temperature to rise; the larger the rotor temperature difference, the permanent magnet experiences a larger temperature fluctuation, which will cause the magnetic domain structure inside the permanent magnet to change, thereby increasing the risk of permanent magnet demagnetization; therefore, through a detailed analysis of the parameters in the permanent magnet motor rotor temperature safety index, the risk of rotor temperature overheating can be discovered in time, and corresponding early warning measures can be taken to avoid motor failures or safety accidents caused by excessive temperature.

[0064] In this embodiment, the permanent magnet motor rotor temperature safety index is compared with the permanent magnet motor rotor temperature safety index threshold value preset in the rotor detection database; if the permanent magnet motor rotor temperature safety index is greater than or equal to the preset permanent magnet motor rotor temperature safety index threshold value, it means that the current temperature condition of the permanent magnet motor rotor is within the safety range, so there is no need to give an early warning prompt for the temperature of the permanent magnet motor rotor; if the permanent magnet motor rotor temperature safety index is less than the preset permanent magnet motor rotor temperature safety index threshold value, it means that the current temperature condition of the permanent magnet motor rotor is lower than the minimum safety limit, which will cause motor performance degradation, damage or safety hazards, so it is necessary to give an early warning prompt for the temperature of the permanent magnet motor rotor. The specific early warning prompt can display a warning message on the display screen, such as "The rotor temperature is too high, please check!".

[0065] Reference Figure 2 As shown, the second aspect of the present invention provides a system, including: a permanent magnet motor operating status detection module, a permanent magnet motor environment monitoring module, a permanent magnet motor rotor temperature detection module, an abnormal temperature warning and rotor detection database.

[0066] The permanent magnet motor operation status detection module is connected to the permanent magnet motor environment monitoring module, the permanent magnet motor environment monitoring module is connected to the temperature detection module of the permanent magnet motor rotor, the temperature detection module of the permanent magnet motor rotor is connected to the abnormal temperature warning module, and the permanent magnet motor operation status detection module, the permanent magnet motor environment monitoring module, the temperature detection module of the permanent magnet motor rotor and the abnormal temperature warning module are all connected to the rotor detection database.

[0067] The permanent magnet motor operation status detection module is used to obtain and analyze the operation data of the permanent magnet motor, obtain the permanent magnet motor operation stability index, and compare it with the permanent magnet motor operation stability index limit value preset in the rotor detection database to obtain a comparison result, and finally determine whether it is necessary to issue an early warning prompt for the operation status of the permanent magnet motor based on the comparison result.

[0068] The permanent magnet motor environment monitoring module is used to obtain the environmental data of the permanent magnet motor, and perform a comprehensive analysis with the permanent magnet motor operation stability index to obtain the permanent magnet motor environmental impact index, and match the permanent magnet motor environmental impact index with the reference rotor temperature characteristic data corresponding to each permanent magnet motor environmental impact index interval preset in the rotor detection database to obtain the reference rotor temperature characteristic data corresponding to the permanent magnet motor in the current environment.

[0069] The temperature detection module of the permanent magnet motor rotor is used to detect the temperature characteristics of the permanent magnet motor rotor through the temperature detection component, thereby obtaining the temperature characteristic data of the permanent magnet motor rotor, and comprehensively analyze the temperature characteristic data of the permanent magnet motor rotor and the reference rotor temperature characteristic data to obtain the permanent magnet motor rotor temperature safety index.

[0070] The abnormal temperature warning module is used to compare the permanent magnet motor rotor temperature safety index with the permanent magnet motor rotor temperature safety index threshold preset in the rotor detection database. If the permanent magnet motor rotor temperature safety index is less than the preset permanent magnet motor rotor temperature safety index threshold, an early warning prompt is issued for the temperature of the permanent magnet motor rotor.

[0071] The rotor detection database is used to store a preset permanent magnet motor operation stability index limit value, reference rotor temperature characteristic data corresponding to each preset permanent magnet motor environmental impact index interval, a preset permanent magnet motor rotor temperature safety index threshold, an operation stability index corresponding to a preset average efficiency unit value, a preset reference speed, a preset reference torque, a preset reference magnetic flux, a preset reference temperature, a preset reference humidity, an environmental impact index corresponding to a preset dust particle average concentration unit value, an environmental impact index corresponding to a preset electromagnetic average interference intensity unit value, a preset air flow reference speed, an environmental impact index corresponding to a preset permanent magnet motor operation stability index, a preset allowable temperature of the permanent magnet motor rotor, a safety index corresponding to a preset temperature difference unit value, a preset reference heat capacity of the permanent magnet motor rotor, a preset reference thermal resistance of the permanent magnet motor rotor, and a preset heat dissipation power limit value of the permanent magnet motor rotor.

[0072] A third aspect of the present invention provides a motor rotor structure of a permanent magnet motor rotor temperature detection method, characterized in that it includes: a temperature detection component and a light source speed measurement component.

[0073] The temperature detection component is used to detect the temperature characteristics of the permanent magnet motor rotor.

[0074] The light source speed measuring component is used to detect the average speed of the permanent magnet motor during an operation detection cycle.

[0075] In this embodiment, the temperature detection component and the light source speed measurement component are both arranged on the inner shaft of the rotor, as shown in the attached Figure 3 The partial cross-sectional structural diagram of the rotor structure of the present invention placed in the motor and the attached Figure 5 As shown in the schematic diagram of the three-dimensional structure of the rotor inner shaft of the present invention, a rotor inner shaft 3 is rotatably arranged in the rotor outer shaft 1 through two bearings 4. Its main function is to fix the temperature detection component. The shaft does not rotate with the rotor outer shaft 1. At the same time, an inner shaft limit plate 5 is fixedly arranged at one end of the rotor inner shaft 3. The inner shaft limit plate is connected to the rotor outer shaft 1 for relative rotation. The inner shaft limit plate 5 is used to prevent the rotor inner shaft 3 from moving left and right.

[0076] As attached Figure 4As shown in the partial cross-sectional schematic diagram of the temperature detection component of the present invention, it is the corresponding structure of the temperature detection component, a slide groove 8 in a circumferential array is arranged on the rotor inner shaft 3, a wiring harness disk 7 is slidably arranged on the outer side of the rotor inner shaft 3, and a plurality of thermal sensors 11 are arranged in a circumferential array on the outer side of the wiring harness disk 7. The inner circle of the wiring harness disk 7 matches the outer diameter of the rotor inner shaft 3. At the same time, a coaxial magnetic pole driving block 9 is arranged on the rotor inner shaft 3, and the magnetic pole driving block 9 is connected to the wiring harness disk 7 through a connecting rod 10. The connecting rod is slidably arranged in the slide groove 8. At the same time, a guide stator magnetic pole 6 is arranged inside the rotor inner shaft 3, wherein the thermal sensor 11 is used to detect the motor rotor temperature in real time. The thermal sensor 11 is detachable, and the installation quantity and arrangement form can be selected according to the detection accuracy. The tail of the thermal sensor 11 can be connected to the wiring harness disk 7, and the wiring harness disk 7 pre-buries the wiring harness in advance. The thermal sensor 11 transmits the temperature signal through the pre-buried wiring harness of the wiring harness disk 7 and the through hole on the magnetic pole driving block 9.

[0077] During the detection process, the motor is blocked and the temperature rises fastest when low speed and high torque are output. The energized coil disk in the harness disk 7 moves axially in the motor under the action of the alternating magnetic poles on the guide rail, thereby accurately detecting local high temperature areas.

[0078] Also attached Figure 4 It can be seen from the partial cross-sectional schematic diagram of the temperature detection component that in order to ensure the accuracy during the sliding process, two harness disks 7 are installed on the same magnetic pole driving block 9.

[0079] The structure of the light source speed measurement component includes Figure 6 The present invention's rotor inner shaft three-dimensional partial enlargement (I) structural schematic diagram to the attached Fig. 9 The wiring harness tray of the present invention is a three-dimensional (second) structural schematic diagram, from the attached Figure 6 It can be seen from the three-dimensional partial enlargement (I) structural schematic diagram of the rotor inner shaft of the present invention that there is a fixed code disk 12 fixedly connected to the rotor outer shaft 1 in the middle of the rotor inner shaft 3, and a plurality of code disk light holes 13 in a circular array are arranged on the fixed code disk 12. At the same time, temperature detection components are arranged on both sides of the fixed code disk 12, and signal light sources 14 and photosensitive signal receivers 15 are respectively arranged on the two harness disks 7 on the opposite sides of the two temperature detection components.

[0080] The principle is as follows: when the motor rotates, the light source and the light hole 13 of the code disk are in a straight line, and the light passes through the light hole 13 of the code disk and shines on the photosensitive signal receiver 15 to generate a voltage signal. When the motor rotates, the light source and the light hole 13 of the code disk are not in a straight line, the photosensitive signal receiver 15 does not generate a voltage signal due to the lack of light source. Therefore, during the rotation of the motor rotor, the photosensitive signal receiver 15 can generate a periodic pulse signal. By detecting the number of pulses, the motor speed can be measured.

[0081] As attached Fig.10 The rotor structure of the present invention is placed in an overall three-dimensional structural schematic diagram in an electronic state, and is mainly provided for the rotor part of a high-power permanent magnet motor. The rotor part mainly includes two parts: an external motor rotor assembly and a rotor outer shaft 1.

[0082] As attached Fig.11 As shown in the three-dimensional structural diagram of the rotor structure of the present invention, the motor rotor assembly 2 is composed of 5 stacked magnetic steel sections, each magnetic steel section is composed of multiple stacked silicon steel sheets, and the rotor punching has multiple evenly arranged V-shaped magnetic steel through holes and corresponding magnetic isolation holes. The parameters of the magnetic isolation holes and the V-shaped magnetic pole structure are the most critical to the design of the electromagnetic scheme. The stacked magnetic steel sections are connected through the motor rotor outer shaft 1 and output torque and speed.

[0083] In this embodiment, both the temperature detection component and the speed detection component are modularly designed, and whether to install them can be determined according to actual needs, so they have good versatility.

[0084] The above contents are merely examples and explanations of the structure of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the structure of the invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. A method for detecting the temperature of a permanent magnet motor rotor, characterized in that: include: S1. Permanent magnet motor operation status detection: obtain and analyze the operation data of the permanent magnet motor, obtain the permanent magnet motor operation stability index, and compare it with the permanent magnet motor operation stability index limit value preset in the rotor detection database to obtain a comparison result, and finally determine whether it is necessary to issue an early warning prompt for the operation status of the permanent magnet motor based on the comparison result; S2. Permanent magnet motor environment monitoring: obtain the environmental data of the permanent magnet motor, and conduct a comprehensive analysis with the permanent magnet motor operation stability index to obtain the permanent magnet motor environmental impact index, match the permanent magnet motor environmental impact index with the reference rotor temperature characteristic data corresponding to each permanent magnet motor environmental impact index interval preset in the rotor detection database, and obtain the reference rotor temperature characteristic data corresponding to the permanent magnet motor in the current environment; S3. Temperature detection of the permanent magnet motor rotor: The temperature characteristics of the permanent magnet motor rotor are detected by the temperature detection component, thereby obtaining the temperature characteristic data of the permanent magnet motor rotor, and the temperature characteristic data of the permanent magnet motor rotor is comprehensively analyzed with the reference rotor temperature characteristic data to obtain the permanent magnet motor rotor temperature safety index; S4. Abnormal temperature warning: compare the permanent magnet motor rotor temperature safety index with the permanent magnet motor rotor temperature safety index threshold preset in the rotor detection database. If the permanent magnet motor rotor temperature safety index is less than the preset permanent magnet motor rotor temperature safety index threshold, a warning prompt is given for the temperature of the permanent magnet motor rotor.

2. The method for detecting the temperature of a permanent magnet motor rotor according to claim 1, characterized in that: The operation data of the permanent magnet motor specifically includes the average input current, average input voltage, average output current, average output voltage, average torque, average electromagnetic induction intensity and average magnetic circuit area of ​​the permanent magnet motor during the operation detection period; The permanent magnet motor is detected by a light source speed measuring component, thereby obtaining the average speed of the permanent magnet motor during the running detection cycle.

3. The method for detecting the temperature of a permanent magnet motor rotor according to claim 2, characterized in that: The specific analysis process of the permanent magnet motor operation stability index is as follows: The average input power of the permanent magnet motor during the operation detection period is obtained by multiplying the average input current of the permanent magnet motor during the operation detection period by the average input voltage; The average output power of the permanent magnet motor during the operation detection period is obtained by multiplying the average output current of the permanent magnet motor during the operation detection period by the average output voltage; The average output power of the permanent magnet motor in the operation detection period is processed by ratio processing with the average input power to obtain the average efficiency of the permanent magnet motor in the operation detection period; The average magnetic flux of the permanent magnet motor during the operation detection period is obtained by multiplying the average electromagnetic induction intensity of the permanent magnet motor during the operation detection period by the average magnetic circuit area; The average efficiency, average speed, average torque and average magnetic flux of the permanent magnet motor during the operation detection period are comprehensively analyzed to obtain the permanent magnet motor operation stability index.

4. The method for detecting the temperature of a permanent magnet motor rotor according to claim 3, characterized in that: The specific process of judging whether it is necessary to give an early warning prompt for the operation status of the permanent magnet motor according to the comparison result is as follows: If the permanent magnet motor operation stability index is greater than or equal to the preset permanent magnet motor operation stability index limit value, the comparison result is recorded as the first comparison result; otherwise, if the permanent magnet motor operation stability index is less than the preset permanent magnet motor operation stability index limit value, the comparison result is recorded as the second comparison result; If the comparison result is the second comparison result, it is necessary to give an early warning prompt for the running state of the permanent magnet motor.

5. The method for detecting the temperature of a permanent magnet motor rotor according to claim 1, characterized in that: The environmental data of the permanent magnet motor specifically includes the temperature, humidity, air flow velocity, dust particle concentration and electromagnetic interference intensity of the environment of the permanent magnet motor at each environmental detection time point during the operation cycle; The temperature, humidity, air flow velocity, dust particle concentration and electromagnetic interference intensity of the environment to which the permanent magnet motor belongs at each environmental detection time point during the operation cycle are summed up respectively to obtain the total temperature, total humidity, total air flow velocity, total dust particle concentration and total electromagnetic interference intensity of the environment to which the permanent magnet motor belongs during the operation cycle; Obtain the number of environmental detections of the environment to which the permanent magnet motor belongs during the operation cycle; The total temperature, total humidity, total air flow speed, total dust particle concentration and total electromagnetic interference intensity of the environment to which the permanent magnet motor belongs during the operating cycle are divided by the number of environmental detections of the environment to which the permanent magnet motor belongs during the operating cycle, and the average temperature, average humidity, average air flow speed, average dust particle concentration and average electromagnetic interference intensity of the environment to which the permanent magnet motor belongs during the operating cycle are obtained.

6. The method for detecting the temperature of a permanent magnet motor rotor according to claim 5, characterized in that: The specific analysis process of the permanent magnet motor environmental impact index is as follows: The average temperature, average humidity, average air flow speed, average dust particle concentration, average electromagnetic interference intensity and permanent magnet motor operation stability index of the environment in which the permanent magnet motor is located during the operation cycle are comprehensively analyzed to obtain the permanent magnet motor environmental impact index.

7. The method for detecting the temperature of a permanent magnet motor rotor according to claim 1, characterized in that: The temperature characteristic data of the permanent magnet motor rotor specifically includes the maximum temperature, average heat capacity, average thermal resistance and average heat dissipation power of the rotor during the operation cycle of the permanent magnet motor; The reference rotor temperature characteristic data corresponding to the permanent magnet motor in the current environment specifically includes the allowable temperature, reference thermal capacity, reference thermal resistance and heat dissipation power limit value of the permanent magnet motor rotor.

8. The method for detecting the temperature of a permanent magnet motor rotor according to claim 7, characterized in that: The specific analysis process of the permanent magnet motor rotor temperature safety index is as follows: Performing difference processing on the maximum temperature of the rotor of the permanent magnet motor during the operation cycle and the average temperature of the environment to which the permanent magnet motor belongs during the operation cycle, to obtain the temperature difference of the rotor of the permanent magnet motor during the operation cycle; The maximum temperature, temperature difference, average heat capacity, average thermal resistance, average heat dissipation power of the permanent magnet motor rotor during the operation cycle, the allowable temperature of the permanent magnet motor rotor, the reference heat capacity, reference thermal resistance and the limit value of heat dissipation power are comprehensively analyzed to obtain the permanent magnet motor rotor temperature safety index. The specific analysis method is as follows: ； In the formula, is the permanent magnet motor rotor temperature safety index, e is the natural constant, is the maximum temperature of the rotor of the permanent magnet motor during its operation cycle, The allowable temperature of the permanent magnet motor rotor preset in the rotor detection database, is the temperature difference of the rotor of the permanent magnet motor during its operation cycle, The safety index corresponding to the temperature difference unit value preset in the rotor detection database, is the average heat capacity of the rotor of the permanent magnet motor during its operation cycle, The reference thermal capacity of the permanent magnet motor rotor preset in the rotor detection database, is the average thermal resistance of the rotor of the permanent magnet motor during its operation cycle, The reference thermal resistance of the permanent magnet motor rotor preset for the rotor detection database, is the average heat dissipation power of the rotor of the permanent magnet motor during its operation cycle, The heat dissipation power limit value of the permanent magnet motor rotor preset in the rotor detection database.

9. A temperature detection system for a permanent magnet motor rotor, using the temperature detection method for a permanent magnet motor rotor as claimed in any one of claims 1 to 8, characterized in that: include: The permanent magnet motor operation status detection module is used to obtain and analyze the operation data of the permanent magnet motor, obtain the operation stability index of the permanent magnet motor, and compare it with the permanent magnet motor operation stability index limit value preset in the rotor detection database to obtain a comparison result, and finally determine whether it is necessary to issue an early warning prompt for the operation status of the permanent magnet motor according to the comparison result; The permanent magnet motor environment monitoring module is used to obtain the environmental data of the permanent magnet motor, and conduct a comprehensive analysis with the permanent magnet motor operation stability index to obtain the permanent magnet motor environmental impact index, match the permanent magnet motor environmental impact index with the reference rotor temperature characteristic data corresponding to each permanent magnet motor environmental impact index interval preset in the rotor detection database, and obtain the reference rotor temperature characteristic data corresponding to the permanent magnet motor in the current environment; The temperature detection module of the permanent magnet motor rotor is used to detect the temperature characteristics of the permanent magnet motor rotor through the temperature detection component, thereby obtaining the temperature characteristic data of the permanent magnet motor rotor, and comprehensively analyze the temperature characteristic data of the permanent magnet motor rotor with the reference rotor temperature characteristic data to obtain the temperature safety index of the permanent magnet motor rotor; The abnormal temperature warning module is used to compare the permanent magnet motor rotor temperature safety index with the permanent magnet motor rotor temperature safety index threshold preset in the rotor detection database. If the permanent magnet motor rotor temperature safety index is less than the preset permanent magnet motor rotor temperature safety index threshold, an early warning prompt is issued for the temperature of the permanent magnet motor rotor.

10. A permanent magnet motor rotor structure, using the permanent magnet motor rotor temperature detection method according to any one of claims 1 to 8, characterized in that: include: The rotor outer shaft has a motor rotor assembly disposed outside the rotor outer shaft, and is characterized in that: a rotor inner shaft that does not rotate with the rotor outer shaft is disposed inside the rotor outer shaft; A temperature detection component, used to detect the temperature characteristics of the permanent magnet motor rotor; The light source speed measuring component is used to detect the average speed of the permanent magnet motor during the running detection cycle.

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