Field detection method and device for field loss of excitation fault of permanent magnet synchronous traction machine of elevator

Abstract

The invention discloses a field detection method and device for an excitation loss fault of an elevator permanent magnet synchronous traction machine, and relates to the technical field of elevator fault detection.The detection support comprises an end face switching fixing support and a three-jaw chuck, and the end face switching fixing support is fixedly connected to the outer side of an end cover of a traction wheel; the three-jaw chuck is fixed to the outer side of the end face switching fixing support and used for fixing a universal sleeve of the electric wrench. And the electric wrench can drive the traction wheel to rotate by clamping an outer hexagonal bulge at the central position of the end face adapter fixing bracket through a universal sleeve of the electric wrench. According to the field detection method and device for the excitation loss fault of the elevator permanent magnet synchronous traction machine, the excitation loss degree of the permanent magnet of the elevator permanent magnet synchronous traction machine can be accurately, simply and efficiently judged, the excitation loss phenomenon of the permanent magnet can be found in time, safe operation of an elevator is guaranteed, and industry development is promoted.

Description

Technical Field

[0001] This invention relates to the field of elevator fault detection technology, and in particular to a method and apparatus for on-site detection of demagnetization faults in elevator permanent magnet synchronous traction machines. Background Technology

[0002] Permanent magnet synchronous traction machines for elevators have been widely used due to their small size, high efficiency, and wide applicability, essentially replacing geared traction machines. However, these machines generate significant heat during operation. When the internal permanent magnets reach their maximum operating temperature, irreversible demagnetization occurs; even after cooling, their magnetism cannot return to its pre-demagnetization state. Furthermore, vibration, alternating magnetic fields, and chemical corrosion can all reduce the magnetism of the permanent magnets. The inherent structure of permanent magnet synchronous traction machines makes on-site disassembly and assembly extremely difficult, technically demanding, costly, and prone to damage. Moreover, conventional instruments cannot be used to externally detect the magnetism of the permanent magnets, making it difficult to detect demagnetized magnets and posing a safety hazard to elevator operation.

[0003] Therefore, there is an urgent need to design an accurate, simple, and efficient method for determining the degree of demagnetization of permanent magnets in elevator permanent magnet synchronous traction machines, so as to detect the demagnetization phenomenon in a timely manner, ensure the safe operation of elevators, and promote the development of the industry. Summary of the Invention

[0004] The purpose of this invention is to provide a method and apparatus for on-site detection of demagnetization faults in elevator permanent magnet synchronous traction machines, so as to solve the problems existing in the prior art. It can accurately, simply and efficiently determine the degree of demagnetization of permanent magnets in elevator permanent magnet synchronous traction machines, detect the demagnetization phenomenon of permanent magnets in a timely manner, ensure the safe operation of elevators, and promote the development of the industry.

[0005] To achieve the above objectives, the present invention provides the following solution: This invention provides a method for on-site detection of demagnetization faults in elevator permanent magnet synchronous traction machines, comprising the following steps: Remove the traction rope from the traction sheave and fix the testing bracket to the end cap of the traction sheave; An electric wrench and its universal socket are fixedly installed on the testing bracket to ensure that the testing bracket and the traction wheel are on the same center line, and to ensure that the universal socket of the electric wrench is fully engaged with the bolt fixed to the center of the traction wheel. The electric wrench continuously applies torque until the traction wheel rotates. It stops after the permanent magnet synchronous traction machine rotor rotates one tooth angle. The final torque is recorded and uploaded. This torque is the tooth torque of each tooth. Repeat the above steps until the rotor of the permanent magnet synchronous traction machine has rotated one revolution and then stop. Analyze and obtain the minimum cogging torque data T for a single measurement. T refers to the minimum cogging torque value after the rotor has rotated one revolution. After continuous measurement for n months, the data analysis was performed using the fixed threshold method and the sliding window algorithm to determine the demagnetization status of the permanent magnet synchronous traction machine.

[0006] Preferably, the fixed threshold method includes: the manufacturer defining a threshold, setting an early warning value a1, a mid-term warning value a2, and a severe warning value a3. If the measured observed value is greater than the early warning value a1 but less than the mid-term warning value a2, the number of tests needs to be increased and the focus should be on observation; if the measured observed value is greater than the mid-term warning value a2 but less than the severe warning value a3, it needs to be evaluated before continued use; if the measured observed value is greater than the severe warning value a3, it is determined that the permanent magnet synchronous traction machine 13 has suffered severe demagnetization and is in an unusable state.

[0007] Preferably, the sliding window algorithm includes: analyzing the goodness of fit of the slope data; in the first case, if the coefficient of determination... ≥0.30: The explanatory power of the trend is moderate to high. Combined with p<0.05, the slope data can be considered to have a high degree of fit. In the second scenario, if Although the linear fit is high and the trend explanatory power is moderate to high, the slope significance test is not up to standard. The trend is likely caused by random noise (not a true demagnetization trend). The slope fit cannot be considered high and cannot be used as a basis for judging the demagnetization of the traction machine. Further data observation is needed.

[0008] In the third case, if 0.15 ≤ <0.30: The trend exists but is affected by noise. Combined with p<0.10, it can serve as an early warning basis for the demagnetization fault of the permanent magnet synchronous traction machine. The fourth case is when 0.15 ≤ The linear fit is moderate with p < 0.30 and p ≥ 0.10, indicating a weak trend that is affected by noise. The slope significance test is not up to standard, and the trend is almost caused by random noise (not a true demagnetization trend). It cannot be used as an early warning basis for traction machine demagnetization faults and needs to be re-analyzed after noise interference is eliminated. The fifth scenario, if <0.15: The linear fit has weak explanatory power, and the slope conclusion has low fit. Therefore, the slope conclusion is no longer used. In either the first or third scenario, if the slope conclusion meets the fitting criteria and the percentage decrease α ≤ 4%, the permanent magnet synchronous traction machine is operating normally. If the percentage decrease is 4% < α ≤ 8%, an early warning is issued, requiring increased testing frequency and inspection of the operating environment. If 8% < α ≤ 12% or two consecutive early warnings are issued, a medium warning is issued, and the permanent magnet synchronous traction machine needs to be evaluated to ensure normal operation. If α > 12%, the permanent magnet synchronous traction machine should be immediately shut down and a comprehensive inspection should be conducted.

[0009] This invention also provides an on-site detection device for demagnetization faults in elevator permanent magnet synchronous traction machines, comprising: The testing bracket includes an end-face adapter fixing bracket and a three-jaw chuck. The end-face adapter fixing bracket is fixedly connected to the outside of the end cover of the traction sheave, and the three-jaw chuck is fixed to the outside of the end-face adapter fixing bracket. The universal socket of the electric wrench is fixedly connected to the three-jaw chuck, and the universal socket of the electric wrench is connected to the external hexagonal protrusion on the end face adapter fixing bracket.

[0010] Preferably, the multiple end cap screws on the traction sheave are replaced with multiple internal and external threaded hexagonal bolts; the end face adapter fixing bracket is provided with multiple hexagonal bolts, one end of each hexagonal bolt is fixedly connected to the corresponding internal and external threaded hexagonal bolt, and the end face adapter fixing bracket is fixed to the internal and external threaded hexagonal bolts.

[0011] Preferably, the three-jaw chuck includes a three-jaw chuck fixing base, one side of which is fixedly connected to the end face adapter fixing bracket, and the other side is fixedly connected to a three-jaw chuck positioning plate; a jaw assembly is fixedly provided between the three-jaw chuck positioning plate and the three-jaw chuck fixing base; a coaxial through hole is provided on the three-jaw chuck fixing base, the end face adapter fixing bracket, and the jaw assembly; the universal socket of the electric wrench passes through the coaxial through hole and is fixed by the jaw assembly.

[0012] Preferably, the chuck assembly includes a three-jaw chuck moving and limiting disc and chuck jaws; the three-jaw chuck moving and limiting disc has a coaxial through hole at its center, and three smooth arc-shaped grooves are provided around the three-jaw chuck moving and limiting disc, within which the chuck jaws are movably disposed; the three-jaw chuck positioning disc has three radially arranged strip-shaped positioning grooves around its circumference, and the outer side of the chuck jaws can engage with the corresponding strip-shaped positioning grooves; the three chuck jaws can securely hold the universal socket of the electric wrench.

[0013] Preferably, the end face adapter fixing bracket has an external hexagonal protrusion at its center; the output shaft of the electric wrench is connected to a universal sleeve, and the universal sleeve of the electric wrench can be fixedly engaged with the external hexagonal protrusion.

[0014] Preferably, the end face adapter fixing bracket has a disc-shaped structure, and the end face adapter fixing bracket is provided with a plurality of radial slots. The radial slots are used to pass through the external hexagonal bolts. The external hexagonal bolts can move radially along the end face adapter fixing bracket within the radial slots to be coaxially fixed with the internal and external thread external hexagonal bolts on the end caps of traction sheaves of different sizes.

[0015] Preferably, one side of the three-jaw chuck fixing base is fixedly connected to the end face adapter fixing bracket by a plurality of countersunk hexagonal bolts.

[0016] The present invention achieves the following technical effects compared to the prior art: This invention only requires installing a detection bracket on the outside of the traction sheave's end cover, and the electric wrench used is a widely available tool, low in cost and highly applicable. Compared to static measurement methods using torque gauges, the electric wrench used in this invention can apply and detect torque more accurately, reducing human error, and the data can be analyzed online in real time, leading to quick conclusions and facilitating rapid detection. By reading the torque of the electric wrench, the magnitude of the traction machine's cogging torque can be obtained, which is convenient, fast, simple, and reliable. Real-time online analysis can be performed directly to quickly determine whether the elevator traction machine has a demagnetization fault, and long-term trend analysis can also be performed to help maintenance personnel determine whether the elevator needs repair. Early warning can be provided, issuing an initial warning when the demagnetization is small. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the on-site detection device for demagnetization fault of elevator permanent magnet synchronous traction machine in one or more embodiments of the present invention. Figure 2 This is a schematic diagram of the three-jaw chuck fixing base structure of the field detection device for demagnetization fault of elevator permanent magnet synchronous traction machine in one or more embodiments of the present invention. Figure 3 This is a schematic diagram of one side of the end face adapter fixing bracket of the field detection device for demagnetization fault of elevator permanent magnet synchronous traction machine in one or more embodiments of the present invention. Figure 4 This is a front view schematic diagram of the end face adapter fixing bracket of the field detection device for demagnetization fault of elevator permanent magnet synchronous traction machine in one or more embodiments of the present invention. Figure 5This is a schematic diagram of the other side of the end face adapter fixing bracket of the field detection device for demagnetization fault of elevator permanent magnet synchronous traction machine in one or more embodiments of the present invention. Figure 6 This is a schematic diagram of the on-site detection method for demagnetization fault of elevator permanent magnet synchronous traction machine in one or more embodiments of the present invention. Figure 7 A schematic diagram illustrating the specific steps of the on-site detection method for demagnetization fault of elevator permanent magnet synchronous traction machine in one or more embodiments of the present invention.

[0019] In the diagram: 1-Computer; 2-Data cable; 3-Electric wrench; 4-Three-jaw chuck positioning plate; 5-Chuck jaws; 6-Three-jaw chuck moving limit plate; 7-Three-jaw chuck fixing base; 8-External hex bolt; 9-End face adapter fixing bracket; 10-Counterhead internal hex bolt; 11-Internal and external thread external hex bolt; 12-Traction wheel; 13-Permanent magnet synchronous traction machine. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] The purpose of this invention is to provide a method and apparatus for on-site detection of demagnetization faults in elevator permanent magnet synchronous traction machines, so as to solve the problems existing in the prior art. It can accurately, simply and efficiently determine the degree of demagnetization of permanent magnets in elevator permanent magnet synchronous traction machines, detect the demagnetization phenomenon of permanent magnets in a timely manner, ensure the safe operation of elevators, and promote the development of the industry.

[0022] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] Among existing on-site testing methods for elevator permanent magnet synchronous traction machines, the sensor dynamic measurement method and the stepper traction machine static measurement method have high measurement accuracy, but they require coaxial installation of couplings, magnetic powder brakes, stepper motors, and torque sensors on the permanent magnet synchronous traction machine, resulting in a large amount of disassembly work and a complicated installation process, and are rarely used in on-site testing. The static measurement method using a lever force gauge is relatively convenient to install and requires fewer disassembly parts, but its measurement accuracy is not high, and the data cannot be directly quantitatively analyzed, which has significant limitations. To solve this problem, the first objective of this invention is to provide an on-site detection method for demagnetization faults in elevator permanent magnet synchronous traction machines, such as... Figures 1-7 As shown, it includes the following steps: Fix the testing bracket to the end cap of the traction sheave 12; The universal socket of the electric wrench 3 is fixedly installed on the test bracket to ensure that the permanent magnet synchronous traction machine 13, the test bracket and the traction wheel 12 are on the same center line, and to ensure that the universal socket of the electric wrench 3 is fully engaged with the bolt fixed to the center of the traction wheel 12. The electric wrench 3 continuously applies torque until the traction wheel 12 rotates. It stops after the rotor of the permanent magnet synchronous traction machine 13 rotates one tooth angle. The final torque is recorded and uploaded. This torque is the tooth torque of each tooth. Repeat the above steps until the permanent magnet synchronous traction machine 13 stops after rotating one revolution, and analyze to obtain the minimum measurement data T for a single measurement; After continuous measurement for n months, the data analysis was performed using the fixed threshold method and sliding window algorithm to determine the demagnetization status of the permanent magnet synchronous traction machine 13.

[0024] Cogging torque refers to the force that the rotor of the permanent magnet synchronous traction machine 13 tends to remain in certain specific positions when stationary, and its magnitude changes periodically with the relative position of the stator and rotor. This invention designs a detection bracket connected to the end cover of the traction sheave 12. A universal socket of an electric wrench 3 is attached to the external hexagonal protrusion on the detection bracket. The cogging torque is measured and transmitted via the electric wrench 3. Short-term demagnetization is determined using a fixed threshold method, and the long-term trend of the cogging torque is analyzed using a sliding window algorithm to identify the demagnetization process. This invention only requires installing a detection bracket on the outside of the end cover of the traction sheave 12, and the electric wrench 3 used is a widely available tool, low in cost and highly applicable. Compared to static measurement methods using torque measuring instruments, this invention effectively reduces the steps of disassembling parts, and the fixed electric wrench 3 can apply and detect torque more accurately, reducing human error. Furthermore, the data can be analyzed online in real time, leading to quick conclusions and facilitating rapid detection. By reading the torque of the electric wrench 3, the magnitude of the traction machine's cogging torque can be obtained, which is convenient, fast, simple, and reliable. Real-time online analysis can be performed directly to quickly determine whether the elevator traction machine has a demagnetization fault. Long-term trend analysis can also be performed, helping maintenance personnel determine whether the elevator needs repair. Early warning can be provided, issuing an initial warning when the demagnetization is small.

[0025] In one embodiment, the calculation method for each element of the sliding window algorithm is as follows: = SSE SE( ) t= In the formula: n is the number of tests (i.e., the number of torque measurement data sets currently used for linear fitting analysis). The detection time (a relative time value characterizing the detection sequence, with units consistent with the detection cycle, generally using actual time) The arithmetic mean of the detection time, For the i-th measurement data, The predicted value (the theoretical predicted torque value of the i-th measurement calculated using the linear regression equation). For the arithmetic mean of the measured data, The slope (characterizing the rate of change of torque with time; a negative value indicates a continuous decrease in cogging torque, and a larger absolute value indicates a faster decrease). The coefficient of determination (the proportion of torque measurement data that can be explained by the "linear decreasing trend of demagnetization," ranging from [0,1]; the closer to 1, the more likely the torque fluctuation is mainly caused by demagnetization and the less noise interference; the closer to 0, the more likely the torque fluctuation is noise and unrelated to the demagnetization trend), and SSE (the sum of squared errors, the sum of squared deviations between all actual measured torques and fitted predicted torques; directly quantifying the interference intensity of noise on the measurement data; the smaller the value, the closer the actual torque is to the linear trend of demagnetization and the higher the data reliability; the larger the value, the more likely noise masks the true demagnetization trend and the higher the data dispersion), and SE ( The standard error is the slope. (Estimation accuracy) The percentage decrease (representing the relative decrease in torque due to demagnetization from the baseline state to the current detection time). This is the initial cogging torque (i.e., the torque value of the permanent magnet synchronous traction machine under initial normal operating conditions).

[0026] The standard error of the slope, SE, can be calculated by calculating the sum of squared errors (SSE) of the measured values. This allows us to calculate the t-statistic for the entire system (the t-statistic is an important value in statistics that helps determine the significance of differences between sample means. It is mainly used in t-tests to determine whether the observed data deviates significantly from the null hypothesis). Then, by consulting the t-distribution table (a table showing the critical values ​​of the t-distribution), we obtain the p-value for the system (the p-value indicates the probability of a more extreme outcome than the observed sample result when the null hypothesis is true. A smaller p-value indicates a lower probability of the hypothetical situation occurring, and if it does occur, according to the principle of low probability, we have reason to reject the null hypothesis; the smaller the p-value, the stronger our reason for rejecting the null hypothesis. In short, a smaller p-value indicates a more significant result). Generally, p < 0.05 is considered significant, p < 0.10 is considered an initial warning, and p ≥ 0.10 is considered a severe warning.

[0027] The demagnetization determination rules in this embodiment are as follows: Short-term demagnetization: Using a fixed threshold method, the manufacturer defines thresholds for an early warning value (a1), a mid-term warning value (a2), and a severe warning value (a3). If the measured value is greater than the early warning value (a1) but less than the mid-term warning value (a2), the number of tests needs to be increased for focused monitoring. If the measured value is greater than the mid-term warning value (a2) but less than the severe warning value (a3), continued use requires evaluation. If the measured value is greater than the severe warning value (a3), the permanent magnet synchronous traction machine 13 is determined to have suffered severe demagnetization and is unusable.

[0028] Long-term demagnetization trend: By using a sliding window algorithm, we first analyze whether the slope data has a strong fit: if the coefficient of determination ≥0.30: The explanatory power of the trend is moderate to high. Combined with p<0.05, the slope data can be considered to have a high degree of fit. like Although the linear fit is high and the trend explanatory power is moderately high (≥0.30, p≥0.05), the slope significance test fails. The trend is most likely caused by random noise (not a true demagnetization trend); the slope fit cannot be considered high and cannot be used as a basis for judging the demagnetization of the traction machine. Further data observation is needed.

[0029] If 0.15≤ <0.30: The trend exists but is affected by noise. Combined with p<0.10, it can serve as an early warning basis for the demagnetization fault of permanent magnet synchronous traction machine 13. If 0.15≤ The linear fit is moderate with p < 0.30 and p ≥ 0.10, indicating a weak trend that is affected by noise. The slope significance test is not up to standard, and the trend is almost caused by random noise (not a true demagnetization trend). It cannot be used as an early warning basis for traction machine demagnetization faults and needs to be re-analyzed after noise interference is eliminated. like <0.15: The linear fit has weak explanatory power, and the slope conclusion has low fit. Therefore, the slope conclusion is no longer used.

[0030] Under the condition that the slope conclusion meets the fitting standard (the first and third situations mentioned above), when the percentage decrease is 4% < α ≤ 8%, an early warning is issued, requiring increased testing frequency and inspection of the operating environment; when 8% < α ≤ 12% or two consecutive early warnings are issued, a medium warning is issued, and the permanent magnet synchronous traction machine needs to be evaluated to ensure normal operation; when α > 12%, the permanent magnet synchronous traction machine should be immediately shut down and a comprehensive inspection should be carried out. (The threshold can be determined by the manufacturer.) This invention employs a fixed threshold method and a sliding window algorithm for demagnetization analysis. It analyzes short-term demagnetization using single-data analysis and then extracts the decay trend of cogging torque from time-series data to distinguish between normal fluctuations and continuous demagnetization, thus determining the short-term and long-term demagnetization trends of the permanent magnet synchronous traction machine 13. This facilitates its widespread application in the elevator industry.

[0031] like Figure 1 As shown, the second objective of this invention is to provide an on-site detection device for demagnetization faults in elevator permanent magnet synchronous traction machines, including a detection bracket and an electric wrench 3. The detection bracket includes an end face adapter fixing bracket 9 and a three-jaw chuck. The end face adapter fixing bracket 9 is fixedly connected to the outside of the end cover of the traction sheave. The three-jaw chuck is fixed to the outside of the end face adapter fixing bracket 9. The end face adapter fixing bracket 9 does not have a through hole or bolt in the middle, but only has an external hexagonal protrusion on the front for engaging the universal sleeve of the electric wrench 3. The sleeve of the electric wrench 3 is fixedly connected to the three-jaw chuck, and the end of the output shaft of the electric wrench 3 is connected to the external hexagonal protrusion of the end face adapter fixing bracket 9 through the universal sleeve of the electric wrench 3. The electric wrench 3 is connected to a computer 1 via a data cable 2. A torque sensor can be installed at the electric wrench 3. With the data cable 2 and the computer 1, it is convenient to detect, transmit, and store the data at the electric wrench 3.

[0032] To facilitate the installation of the testing bracket, in one embodiment, multiple end cap screws on the traction sheave are first replaced with multiple internal and external threaded hex bolts 11; the three-jaw chuck positioning plate 4, the three-jaw chuck jaws 5, the three-jaw chuck movement limit plate 6, and the three-jaw chuck fixing base 7 are combined together; multiple countersunk internal hex bolts 10 are used to connect the three-jaw chuck fixing base 7 to the end face adapter fixing bracket 9; multiple external hex bolts 8 are used to fix the end face adapter fixing bracket 9 to the internal and external threaded hex bolts 11, thereby achieving the connection between the testing bracket and the traction sheave 12.

[0033] Because the traction sheaves 12 have different specifications, their diameters vary. To broaden the applicability of the device, in one embodiment, the end face adapter fixing bracket 9 has a disc-shaped structure and multiple radial slots are provided around it. External hexagonal bolts 8 are inserted into these radial slots. The width of the radial slots is smaller than the diameter of the end cap of the external hexagonal bolts 8, allowing the external hexagonal bolts 8 to fix the end face adapter fixing bracket 9. The external hexagonal bolts 8 can move radially along the end face adapter fixing bracket 9 within the radial slots. The movement is such that it is coaxially fixed with the internal and external threaded hexagonal bolts 11 on the end caps of traction sheaves 12 of different sizes. When the end cap is smaller, the radial dimension between the internal and external threaded hexagonal bolts 11 and the center of the end cap is smaller. At this time, the position of the external hexagonal bolt 8 in the radial groove can be adjusted so that the external hexagonal bolt 8 moves along the radial groove towards the center until the external hexagonal bolt 8 is coaxial with the corresponding internal and external threaded hexagonal bolt 11. Then, the external hexagonal bolt 8 is tightened so that its fixing thread is connected to the threaded hole on the outside of the internal and external threaded hexagonal bolt 11, thereby achieving fixation.

[0034] In one embodiment, the three-jaw chuck includes a three-jaw chuck fixing base 7. One side of the three-jaw chuck fixing base 7 is fixedly connected to the end face adapter fixing bracket 9 by multiple countersunk hexagon socket head cap screws 10, and the other side is fixedly connected to a three-jaw chuck positioning plate 4. The three-jaw chuck fixing base 7 is provided with six extension internal screws on the side near the end face adapter fixing bracket 9. The extension internal screws of the three-jaw chuck fixing base 7 are connected to the end face adapter fixing bracket 9 using countersunk hexagon socket head cap screws 10 to fix the two. At this time, there is a gap between the three-jaw chuck fixing base 7 and the end face adapter fixing bracket 9. The size of the gap is equal to the axial length of the extension internal screws. This gap is to leave operating space for the subsequent connection of the previously fixed end face adapter fixing bracket 9 and the three-jaw chuck part to the internal and external thread external hexagon socket head cap screws 11 using external hexagon socket head cap screws 8. A jaw assembly is fixed between the three-jaw chuck positioning plate 4 and the three-jaw chuck fixing base 7; the three-jaw chuck fixing base 7, the end face adapter fixing bracket 9, and the jaw assembly are all provided with coaxial through holes; the universal socket of the electric wrench 3 passes through the coaxial through hole; the jaw assembly includes a three-jaw chuck moving limit plate 6 and chuck jaws 5; the three-jaw chuck moving limit plate 6 has a coaxial through hole in its center, and three smooth arc-shaped grooves are provided on the upper ring of the three-jaw chuck moving limit plate 6, within which the chuck jaws 5 are movably mounted; the three-jaw chuck positioning plate 4 has three radially arranged strips on its upper ring. The three chuck jaws 5 are positioned in a shaped groove, and their outer sides can engage with the corresponding shaped grooves. The three chuck jaws 5 move synchronously along their respective shaped grooves, and after moving to any position, the three chuck jaws 5 can always correspond one-to-one with the three shaped grooves. The difference is that when the chuck jaws 5 move to a position close to the coaxial through hole, they will be located at the end of the shaped groove close to the coaxial through hole, and when the chuck jaws 5 move to a position away from the coaxial through hole, they will be located at the end of the shaped groove away from the coaxial through hole. The three chuck jaws 5 can fix and clamp the universal socket of the electric wrench 3.

[0035] In one embodiment, an external hexagonal protrusion is provided at the center of the end face adapter fixing bracket 9, and a universal sleeve is fixedly provided at the end of the output shaft of the electric wrench 3. The universal sleeve can be fixedly snapped into the external hexagonal protrusion, thereby realizing the connection between the universal sleeve of the electric wrench 3 and the traction wheel 12.

[0036] In use, the three-jaw chuck positioning plate 4, three-jaw chuck jaws 5, three-jaw chuck moving limit plate 6, and three-jaw chuck fixing base 7 are assembled together. The lower ends of the three three-jaw chuck jaws 5 can only move within their respective arc-shaped grooves on the three-jaw chuck positioning plate 4, and the upper ends of the three-jaw chuck jaws 5 can only move within their corresponding elongated grooves on the three-jaw chuck positioning plate 4. The positioning and clamping of the three-jaw chuck are achieved by moving the operating lever of the three-jaw chuck moving limit plate 6 left and right. The universal socket of the electric wrench 3 is passed sequentially through the coaxial through holes of the three-jaw chuck positioning plate 4, the three-jaw chuck moving limit plate 6, and the three-jaw chuck fixing base 7. The long rod at the lower end of the three-jaw chuck moving limit plate 6 is moved to achieve radial movement of the three chuck jaws 5, thereby achieving self-centering and fixing of the universal socket of the electric wrench 3. The electric wrench 3 can drive the traction wheel 12 to rotate by connecting the universal socket to the external hexagonal protrusion at the center position of the adapter bracket 9. First, replace the multiple end cap screws on the traction sheave with multiple internal and external threaded hex bolts 11; use multiple countersunk internal hex bolts 10 to connect the three-jaw chuck fixing base 7 to the end face adapter fixing bracket 9; use multiple external hex bolts 8 to fix the end face adapter fixing bracket 9 to the internal and external threaded hex bolts 11. This invention enables rapid elevator demagnetization detection by simply lifting the car and removing the traction rope and installing the detection bracket during on-site testing; the traction machine cogging torque is obtained by reading the torque of the electric wrench 3, which is convenient, fast, simple, and reliable.

[0037] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A method for detecting a field loss fault of an elevator permanent magnet synchronous traction machine in situ, characterized in that: The method comprises the following steps: Fix the detection support on the end cover of the traction sheave; Fix the electric wrench and its universal sleeve on the detection support, ensure that the detection support and the traction sheave are on the same axis, and ensure that the universal sleeve of the electric wrench is completely clamped into the outer hexagonal protrusion of the end face adapter fixing support; The electric wrench continuously applies torque until the traction sheave rotates, and stops after the permanent magnet synchronous traction machine rotor rotates by an angle of one tooth slot, records and uploads the final torque, which is the torque of each tooth slot; Repeat the above steps until the permanent magnet synchronous traction machine stops after rotating one round, and analyze to obtain single minimum measurement tooth slot torque data T; After continuous measurement for n months, use fixed threshold method and sliding window algorithm for data analysis to determine the demagnetization condition of the permanent magnet synchronous traction machine.

2. The method for detecting field weakening fault of elevator permanent magnet synchronous traction machine on site according to claim 1, characterized in that: The fixed threshold method comprises: defining threshold values by the manufacturer, setting early warning value a1, medium-term warning value a2 and serious warning value a3, if the measured observation value is greater than the early warning value a1 and less than the medium-term warning value a2, the detection frequency needs to be increased and the observation needs to be focused; if the measured observation value is greater than the medium-term warning value a2 and less than the serious warning value a3, the device needs to be evaluated and then used; if the measured observation value is greater than the serious warning value a3, it is determined that the permanent magnet synchronous traction machine 13 has serious demagnetization and is in an unusable state.

3. The method for detecting field weakening fault of elevator permanent magnet synchronous traction machine on site according to claim 1, characterized in that: The sliding window algorithm comprises: analyzing the fitting degree of the slope data; The first case, if the decision coefficient ≥0.30, the trend of interpretation is medium, combined with p<0.05 can be considered as a high degree of data fitting slope; The second case, if ≥ 0.30 and p ≥ 0.05, cannot be used as a judgment basis for the loss of excitation of the traction machine, and the data needs to be continuously observed; Third case, if 0.15≤ <0.30, the trend exists but is affected by noise, and the combination p<0.10 can be used as an early warning basis for the initial failure of the permanent magnet synchronous traction machine. The fourth case, if 0.15≤ <0.30 and p≥0.10, cannot be used as the initial warning basis of the traction machine magnetic fault, and needs to be re-analyzed after excluding noise interference; In a fifth case, if <0.15, the slope conclusion is no longer used; In the first or third case, the slope conclusion fitting degree meets the standard, when the decline percentage 4%<α≤8%, early warning is given, the detection frequency needs to be increased and the running environment needs to be checked; when 8%<α≤12% or continuous early warning for two times, medium warning is given, the permanent magnet synchronous traction machine needs to be evaluated to ensure normal use; when α>12%, the permanent magnet synchronous traction machine needs to be stopped immediately and be detected comprehensively.

4. A device for detecting a field loss fault of an elevator permanent magnet synchronous traction machine in situ, characterized in that: It comprises: A detection support comprising an end face adapter fixing support and a three-jaw chuck, the end face adapter fixing support is fixedly connected to the outside of the end cover of the traction sheave, and the three-jaw chuck is fixed to the outside of the end face adapter fixing support; and The universal sleeve of the electric wrench is fixedly connected to the three-jaw chuck, and the universal sleeve of the electric wrench is connected with the outer hexagonal protrusion on the end face adapter fixing support.

5. The device for detecting a field loss fault of an elevator permanent magnet synchronous traction machine on site according to claim 4, characterized in that: Replace the plurality of end cover screws on the traction sheave with a plurality of inner and outer toothed hexagonal bolts; a plurality of outer hexagonal bolts are provided on the end face adapter fixing support, and the outer hexagonal bolts are fixedly connected to the corresponding inner and outer toothed hexagonal bolts, thereby fixing the end face adapter fixing support to the inner and outer toothed hexagonal bolts.

6. The device for detecting field weakening fault of elevator permanent magnet synchronous traction machine on site according to claim 4, characterized in that: The three-jaw chuck comprises a three-jaw chuck fixing base, one side of the three-jaw chuck fixing base is fixedly connected with the end face adapter fixing support, and the other side is fixedly connected with a three-jaw chuck positioning disc; a disc claw assembly is fixedly arranged between the three-jaw chuck positioning disc and the three-jaw chuck fixing base; coaxial through holes are formed in the three-jaw chuck fixing base, the end face adapter fixing support and the disc claw assembly; the universal sleeve of the electric wrench is arranged at the coaxial through holes and is fixed by the disc claw assembly.

7. The device for detecting a field loss fault of an elevator permanent magnet synchronous traction machine on site according to claim 6, characterized in that: The disc claw assembly comprises a three-claw chuck moving limiting disc and a chuck disc claw; the three-claw chuck moving limiting disc is provided with the coaxial through hole in the center, three smooth arc-shaped grooves are annularly arranged on the three-claw chuck moving limiting disc, and the chuck disc claw is movably arranged in the arc-shaped groove; three radial strip-shaped positioning grooves are annularly arranged on the three-claw chuck positioning disc, and the chuck disc claw is capable of being clamped in the corresponding strip-shaped positioning groove; and three chuck disc claws are capable of fixedly clamping the universal sleeve of the electric wrench.

8. The device for detecting field weakening fault of elevator permanent magnet synchronous traction machine on site according to claim 4, characterized in that: The end face adapter fixing support is provided with an outer hexagonal protrusion at the center position; the output shaft of the electric wrench is connected with the universal sleeve, and the universal sleeve of the electric wrench is capable of being fixedly clamped on the outer hexagonal protrusion.

9. The device for detecting field weakening fault of elevator permanent magnet synchronous traction machine on site according to claim 5, characterized in that: The end face adapter fixing support is in a disc structure, and a plurality of radial clamping grooves are annularly arranged on the end face adapter fixing support; the outer hexagonal bolt is arranged in the radial clamping groove; and the outer hexagonal bolt is capable of moving along the radial direction of the end face adapter fixing support in the radial clamping groove, so as to be coaxially fixed with the outer hexagonal bolt on the end cover of different sizes.

10. The device for detecting field weakening fault of elevator permanent magnet synchronous traction machine on site according to claim 6, characterized in that: The three-claw chuck fixing base is fixedly connected with the end face adapter fixing support through a plurality of countersunk inner hexagonal bolts.

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