High-precision variable-frequency and variable-speed asynchronous motor for elevator and use method of variable-frequency and variable-speed asynchronous motor

Abstract

The invention discloses a high-precision variable-frequency and variable-speed asynchronous motor for an elevator and a using method thereof, and relates to the technical field of motors, the high-precision variable-frequency and variable-speed asynchronous motor comprises a dual-redundancy coding system and a motor shell, the dual-redundancy coding system is arranged in the motor shell, and a stator is fixedly mounted at the bottom end of the inner wall of the motor shell; the dual-redundancy coding system comprises a main encoder, an auxiliary encoder and a segmented filtering winding. By means of the dual-redundancy coding system, a dual-channel position detection system is established, the problem that a traditional single encoder is prone to being interfered by torsional deformation to cause positioning deviation is solved, the angle detection precision is improved to + / -0.01 degrees, the fault switching time is shorter than or equal to 3 ms, and the elevator leveling precision is guaranteed.

Description

Technical Field

[0001] This invention relates to the field of electric motor technology, specifically to a high-precision variable frequency speed-regulating asynchronous motor for elevators and its usage method. Background Technology

[0002] Modern society places increasingly higher demands on the functionality and quality of buildings. As an indispensable building facility, elevators directly impact people's living and working experiences. Simultaneously, with the arrival of an aging society, the elderly and disabled are paying greater attention to the ease of use and safety of elevators; high-precision elevator operation can provide them with more convenient and comfortable travel conditions. Furthermore, energy conservation and environmental protection have become a global consensus. Highly efficient and energy-saving elevators using variable frequency speed-regulating asynchronous motors help reduce building energy consumption, aligning with the requirements of sustainable social development.

[0003] Existing variable frequency speed-regulating asynchronous motors cannot meet the speed regulation accuracy requirements of elevators when running at low and high speeds. Moreover, the motors have large torque fluctuations during operation, which can cause vibration and noise during elevator operation.

[0004] Therefore, it is essential to propose a high-precision variable frequency speed-regulating asynchronous motor for elevators and its usage method to solve the problems in the background.

[0005] Patent document CN118100531B discloses a variable frequency speed-regulating high-voltage three-phase asynchronous motor. The above patent achieves heat dissipation inside while maintaining the sealed state of the motor housing, and utilizes the unavoidable vibration during motor operation to enhance heat dissipation outside the motor housing, thereby improving the service life of the three-phase asynchronous motor.

[0006] In summary, one end of the aforementioned patented water inlet pipe connects to the inside of the liquid storage tank after penetrating the motor housing, maintaining the motor housing in a sealed state to dissipate heat from the inside, and using the vibration of the motor during operation to enhance the external heat dissipation of the motor housing, which to some extent improves the service life of the three-phase asynchronous motor. However, for variable frequency speed control asynchronous motors, the speed regulation accuracy is difficult to meet the strict requirements of precise elevator stopping, resulting in deviations in the elevator stopping position and affecting the user experience.

[0007] Therefore, this application proposes a dual-redundant coding system to establish a dual-channel position detection system and a high-precision variable frequency speed-regulating asynchronous motor for elevators that absorbs wideband harmonics, as well as its usage method. Summary of the Invention

[0008] The purpose of this invention is to provide a high-precision variable frequency speed-regulating asynchronous motor for elevators and its usage method, in order to solve the technical problems mentioned in the background art, such as the difficulty in meeting the requirements of precise elevator stopping, and the fact that the high power density of elevators causes localized heating, which affects the high-frequency harmonics generated by the frequency converter, resulting in greater electromagnetic interference.

[0009] To achieve the above objectives, the present invention provides the following technical solution: a high-precision variable frequency speed-regulating asynchronous motor for elevators, comprising a dual-redundant coding system and a motor housing, wherein the dual-redundant coding system is disposed inside the motor housing, and a stator is fixedly installed at the bottom of the inner wall of the motor housing;

[0010] The dual-redundant encoding system includes a main encoder, an auxiliary encoder, and segmented filter windings. A rotating shaft is fixedly installed at the front end of the outer wall of the main encoder. The rear end of the outer wall of the rotating shaft is connected to the auxiliary encoder through a flexible coupling. The main encoder is fixed to the front end cover through a flange. The signal line of the main encoder is connected to the DSP control board through a shielded cable. The segmented filter windings are integrated inside the stator. Each phase of the stator winding is divided into 4 groups. Nanocrystalline filter magnetic rings are inserted between each group of the stator. The slot wedges inside the stator are made of Fe-Si-B amorphous alloy.

[0011] Preferably, a vibration damping base is fixedly installed at the bottom of the outer wall of the motor housing, a lower protective shell is fixedly installed at the bottom of the outer wall of the vibration damping base, and an upper protective shell is fixedly installed at the top of the outer wall of the lower protective shell.

[0012] Preferably, a stator, a rotor, a double-row angular contact bearing, and a shaft are sequentially installed inside the motor housing. The stator is fixedly installed at the bottom of the inner wall of the motor housing. The inner ring of the rotor is fitted onto the outer ring of the shaft. The inner ring of the double-row angular contact bearing is fitted into the shaft journal. Both ends of the shaft are supported on the bearing seats of the motor housing by the double-row angular contact bearings.

[0013] A DSP control board is fixedly installed on the inner wall of the rear end cover of the motor housing. The DSP control board is connected to the main encoder and the auxiliary encoder via a data cable.

[0014] Preferably, the rotor core has 36 spiral cooling grooves inside, and the shaft has hollow cooling pipes inside, which are connected to an external fluorinated liquid circulation system.

[0015] The outer wall of the motor housing is fixedly equipped with corrugated heat dissipation fins, and a PTC heating film is embedded inside the corrugated heat dissipation fins. The surface of the corrugated heat dissipation fins is coated with an aluminum nitride thermal conductive coating. The flexible coupling is connected to the rotating shaft by a key. The input shaft of the auxiliary encoder is connected to the output shaft of the flexible coupling. A mounting bracket is set at the bottom of the outer wall of the flexible coupling. A preload spring is set inside the mounting bracket. A titanium alloy bellows is set inside the flexible coupling. The axial compensation of the titanium alloy bellows is ±0.5mm, and the radial deflection angle is ±0.1°.

[0016] Preferably, the outer ring of the double-row angular contact bearing has an annular hydraulic chamber, which is connected to a servo valve and a piezoelectric ceramic vibration sensor. The DSP control board integrates a fuzzy control module, which receives load torque observer signals and outputs space vector modulation commands.

[0017] The inner layer of the motor housing is equipped with a copper mesh shielding layer, and the outer layer is covered with ferrite absorbing material. The DSP control board integrates a CAN bus interface, which connects the main encoder and the auxiliary encoder simultaneously through differential signal lines.

[0018] Preferably, the spiral cooling groove has a lead angle of 55° and a depth of 3mm, and is connected to the hollow cooling pipe of the rotating shaft through a radial diversion hole, forming a spiral-axial composite cooling path with the spiral cooling groove and the hollow cooling pipe.

[0019] Preferably, the annular hydraulic chamber is filled with magnetorheological fluid, the viscosity of which is adaptive, the oil film thickness is controlled between 50-200 μm by a servo valve, and the piezoelectric ceramic vibration sensor has a sensitivity of 0.01 μm.

[0020] The permeability of the nanocrystalline filter magnetic ring is μ=1.2×105. Each phase winding is divided into four groups: A1, A2, B1, and B2, and the windings are sequentially embedded in the stator slots.

[0021] Preferably, the fluorinated liquid circulation system includes a storage tank, a micro pump, and a condenser. The storage tank is connected to the micro pump, the micro pump is connected to a hollow cooling pipe through a pipeline, the hollow cooling pipe is connected to a spiral cooling tank through a pipeline, the spiral cooling tank is connected to the condenser through a pipeline, and the condenser is connected to the storage tank through a pipeline. The condenser integrates a semiconductor refrigeration chip inside.

[0022] The fluorinated liquid has a boiling point of 56℃, a latent heat of 350kJ / kg, and a circulation flow rate that can be adjusted from 0.5 to 5L / min using a micro pump.

[0023] Preferably, the method of use includes the following steps:

[0024] S1. The main encoder detects the front end angle position of the shaft, and the auxiliary encoder detects the end position. The main encoder serves as the reference, and the auxiliary encoder automatically compensates for the phase difference. The DSP control board performs real-time differential calculations on the detection signals of the main encoder and the auxiliary encoder to compensate for the torsional deformation of the shaft. When the main encoder signal is lost for ≥3ms / deviation>0.5%, the DSP control board switches to the auxiliary encoder.

[0025] The S2 and DSP control boards communicate with the elevator control system via a CAN bus interface, detecting the communication status of the main encoder, auxiliary encoder, fuzzy control module, and servo valve. 99.99% pure argon gas is injected into the sealed interface of the motor housing to replace the internal air until the oxygen content is <0.1%.

[0026] S3. When the output of the frequency converter passes through the segmented windings of the stator, harmonics above 5kHz are absorbed by the nanocrystalline magnetic ring.

[0027] S4. The fluorinated liquid flows from the storage tank through a micro pump along the hollow cooling pipe and spiral cooling tank. After absorbing heat, the fluorinated liquid flows back to the condenser to form the initial cycle. It is then cooled by the action of the semiconductor cooling chip and flows back to the storage tank.

[0028] Preferably, the method of use further includes the following steps:

[0029] S11. Winding A1 serves as the starting end of the A-phase winding and is responsible for receiving and transmitting the initial current signal. Winding A1 is in direct contact with filter ring 1. The signal processed by filter ring 1 is transmitted to winding A2. Winding A2 is connected to the starting segment B1 of phase B. B1 is in contact with filter ring 2. The signal processed by filter ring 2 is transmitted to winding B2.

[0030] S12. The piezoelectric ceramic sensor detects the vibration signal and transmits it to the DSP control board. The DSP control board calculates the compensation amount and feeds it back to the servo valve. At the same time, the fuzzy control module outputs a PWM signal to the servo valve. The servo valve adjusts the viscosity of the magnetorheological fluid to dynamically balance the rotor eccentricity. The fuzzy control module performs fuzzification processing on the load torque observer signal according to the fuzzy control rules. After fuzzy inference and defuzzification processing, it outputs a space vector modulation command.

[0031] S13. When the piezoelectric ceramic vibration sensor detects an abnormal vibration signal, it triggers an emergency stop program. The DSP control board cuts off the motor power supply and uses the feedback information from the main encoder, auxiliary encoder, and piezoelectric ceramic vibration sensor to locate the fault point.

[0032] S41. After absorbing the rotor's heat in the spiral cooling tank, the fluorinated liquid partially vaporizes. When the load rate is >70%, the wavy heat dissipation fins assist in the cooling of the fluorinated liquid.

[0033] Compared with the prior art, the beneficial effects of the present invention are:

[0034] 1. This invention establishes a dual-channel position detection system through a dual-redundant coding system, which solves the problem of positioning deviation caused by torsional deformation interference in traditional single encoders. This improves the angle detection accuracy to ±0.01°, the fault switching time to ≤3ms, and ensures the leveling accuracy of elevators.

[0035] 2. This invention achieves a three-dimensional heat dissipation path through a spiral-axial composite cooling path, solving the problem of local overheating caused by high power density. It utilizes the latent heat of phase change to enhance heat transfer, keeping the rotor temperature rise below 45K and improving the continuous overload capacity by 40%.

[0036] 3. This invention achieves wideband harmonic absorption through segmented filter windings, solving the problem of electromagnetic interference and iron loss caused by high-frequency harmonics generated by the frequency converter, ensuring clean current, improving motor operating efficiency, and extending motor service life;

[0037] 4. This invention achieves dynamic adjustment of bearing stiffness and damping characteristics through magnetorheological fluid, solving the problem of excessive vibration caused by sudden load changes, avoiding motor damage and elevator safety accidents, and improving the safety and reliability of motor and elevator systems. Attached Figure Description

[0038] Figure 1 This is a front view structural diagram of the present invention;

[0039] Figure 2 This is a schematic diagram of the dual-redundant coding system structure of the present invention;

[0040] Figure 3 This is a schematic diagram of the DSP control board structure of the present invention;

[0041] Figure 4 This is a schematic diagram of the spiral-axial composite cooling path structure of the present invention;

[0042] Figure 5 This is a schematic diagram of the fluorinated liquid circulation system of the present invention;

[0043] Figure 6 This is a schematic diagram of the aluminum nitride thermally conductive coating structure of the present invention.

[0044] In the diagram: 1. Main encoder; 2. Auxiliary encoder; 3. Motor housing; 4. Shaft; 5. Flexible coupling; 6. Nanocrystalline filter magnetic ring; 7. Flange; 8. Stator; 9. Front cover; 10. Shielded cable; 11. DSP control board; 12. Vibration damping base; 13. Lower protective housing; 14. Upper protective housing; 15. Rotor; 16. Spiral cooling groove; 17. Hollow cooling pipe; 18. Double row angular contact bearing; 19. Annular hydraulic chamber; 20. Servo valve; 21. Piezoelectric ceramic vibration sensor; 22. Fuzzy control module; 23. Radial shunt hole; 24. CAN bus interface; 25. Differential signal line; 26. Corrugated heat sink fins; 27. PTC heating film; 28. Aluminum nitride thermal conductive coating; 29. ​​Liquid reservoir; 30. Micro pump; 31. Condenser; 32. Mounting bracket; 33. Preload spring; 34. Semiconductor cooling chip; 35. Copper mesh shielding layer. Detailed Implementation

[0045] 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.

[0046] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0047] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0048] Please see Figure 1 , Figure 2 and Figure 3This invention provides an embodiment of a high-precision variable frequency speed-regulating asynchronous motor for elevators, comprising a dual-redundant encoding system and a motor housing 3. The dual-redundant encoding system is disposed inside the motor housing 3, and a stator 8 is fixedly installed at the bottom of the inner wall of the motor housing 3. The dual-redundant encoding system includes a main encoder 1, an auxiliary encoder 2, and segmented filtering windings. A rotating shaft 4 is fixedly installed at the front end of the outer wall of the main encoder 1, and the rear end of the outer wall of the rotating shaft 4 is connected to the auxiliary encoder 2 through a flexible coupling 5. The main encoder 1 is fixed to the front end cover 9 through a flange 7, and the signal line of the main encoder 1 is connected to a DSP control board 11 through a shielded cable 10. The segmented filtering windings are integrated inside the stator 8, and each phase winding of the stator 8 is divided into 4 groups. Nanocrystalline filter magnetic rings 6 are inserted between each group of the stator 8, and the slot wedges inside the stator 8 are made of Fe-Si-B amorphous alloy.

[0049] A vibration damping base 12 is fixedly installed at the bottom of the outer wall of the motor housing 3. A lower protective housing 13 is fixedly installed at the bottom of the outer wall of the vibration damping base 12. An upper protective housing 14 is fixedly installed at the top of the outer wall of the lower protective housing 13.

[0050] Furthermore, the vibration damping base 12 is fixedly installed at the bottom of the outer wall of the motor housing 3, then the lower protective housing 13 is installed at the bottom of the outer wall of the vibration damping base 12, and finally the upper protective housing 14 is fixedly installed at the top of the outer wall of the lower protective housing 13. Inside the motor housing 3, the stator 8 is first fixedly installed at the bottom of the inner wall of the motor housing 3. The inner ring of the rotor 15 is fitted onto the outer ring of the shaft 4, the inner ring of the double-row angular contact bearing 18 is fitted onto the journal of the shaft 4, and then both ends of the shaft 4 are supported on the bearing seats of the motor housing 3 by the double-row angular contact bearing 18. The DSP control board 11 is fixedly installed on the inner wall of the rear end cover of the motor housing 3.

[0051] The main encoder 1 is fixed to the silicon nitride ceramic front cover 9 by a titanium alloy flange 7. Thermal grease is filled between the flange 7 and the rotating shaft 4. The mounting bracket 32 ​​is made of Invar alloy. When the motor is started, the rotating shaft 4 is rotated. The main encoder 1 detects the front corner position of the rotating shaft 4, and the auxiliary encoder 2 detects the end position. The detection signals of the main encoder 1 and the auxiliary encoder 2 are processed in real time by the DSP control board 11.

[0052] The main encoder 1 samples the front end angular position θ1 of the shaft 4 at 1MHz, and the auxiliary encoder 2 synchronously collects the end position θ2. The DSP calculates the torsional deformation Δθ=θ1-θ2 in real time. When Δθ>0.03°, the space vector modulator adjusts the q-axis current to generate reverse compensation torque. If the main encoder 1 signal is lost for ≥3ms, the DSP automatically switches to the auxiliary encoder 2 and activates the sliding mode observer to perform position estimation.

[0053] Please see Figure 1 , Figure 3 and Figure 6 The present invention provides an embodiment of a high-precision variable frequency speed-regulating asynchronous motor for elevators. Inside the motor housing 3, a stator 8, a rotor 15, a double-row angular contact bearing 18, and a rotating shaft 4 are sequentially installed. The stator 8 is fixedly installed at the bottom of the inner wall of the motor housing 3. The inner ring of the rotor 15 is fitted onto the outer ring of the rotating shaft 4. The inner ring of the double-row angular contact bearing 18 is fitted into the journal of the rotating shaft 4. Both ends of the rotating shaft 4 are supported on the bearing seats of the motor housing 3 by the double-row angular contact bearing 18. A DSP control board 11 is fixedly installed on the inner wall of the rear end cover of the motor housing 3. The DSP control board 11 is connected to the main encoder 1 and the auxiliary encoder 2 via a data cable.

[0054] The rotor 15 has 36 spiral cooling grooves 16 inside its iron core, and the shaft 4 has a hollow cooling pipe 17 inside, which is connected to an external fluorinated liquid circulation system. The outer wall of the motor housing 3 is fixedly equipped with corrugated heat dissipation fins 26, and a PTC heating film 27 is embedded inside the corrugated heat dissipation fins 26. The surface of the corrugated heat dissipation fins 26 is coated with an aluminum nitride thermal conductive coating 28. The flexible coupling 5 is connected to the shaft 4 by a key. The input shaft of the auxiliary encoder 2 is connected to the output shaft of the flexible coupling 5. The bottom of the outer wall of the flexible coupling 5 is provided with a mounting bracket 32, and a preload spring 33 is provided inside the mounting bracket 32. The flexible coupling 5 is provided with a titanium alloy bellows, with an axial compensation of ±0.5mm and a radial deflection angle of ±0.1°.

[0055] Furthermore, the main encoder 1 is fixed to the front cover 9 via flange 7. A rotating shaft 4 is fixedly installed on the front end of the outer wall of the main encoder 1, and the rear end of the outer wall of the rotating shaft 4 is connected to the auxiliary encoder 2 via a flexible coupling 5. The signal line of the main encoder 1 is connected to the DSP control board 11 via shielded cable 10. At the same time, the DSP control board 11 is connected to the main encoder 1 and the auxiliary encoder 2 via data line, and integrates a CAN bus interface 24. The CAN bus interface 24 is connected to both the main encoder 1 and the auxiliary encoder 2 via differential signal line 25.

[0056] Fluorinated liquid is injected into the storage tank 29, and the micro pump 30 is started, so that the fluorinated liquid flows from the storage tank 29 through the micro pump 30 along the hollow cooling pipe 17 and the spiral cooling tank 16. After absorbing heat, the fluorinated liquid flows back to the condenser 31 to form the initial cycle.

[0057] Please see Figure 1 , Figure 2 and Figure 4The present invention provides an embodiment of a high-precision variable frequency speed-regulating asynchronous motor for elevators. The outer ring of the double-row angular contact bearing 18 has an annular hydraulic chamber 19, which is connected to a servo valve 20 and a piezoelectric ceramic vibration sensor 21. The DSP control board 11 integrates a fuzzy control module 22, which receives load torque observer signals and outputs space vector modulation commands. The inner layer of the motor housing 3 is provided with a copper mesh shielding layer 35, and the outer layer is covered with ferrite absorbing material. The DSP control board 11 integrates a CAN bus interface 24, which is connected to the main encoder 1 and the auxiliary encoder 2 simultaneously through differential signal lines 25.

[0058] The spiral cooling groove 16 has a lead angle of 55° and a depth of 3mm. It is connected to the hollow cooling pipe 17 of the rotating shaft 4 through a radial diversion hole 23. The spiral cooling groove 16 and the hollow cooling pipe 17 form a spiral-axial composite cooling path.

[0059] S41. After absorbing heat from the rotor 15 in the spiral cooling tank 16, the fluorinated liquid partially vaporizes. When the load rate is >70%, the wave-shaped heat dissipation fins 26 assist the fluorinated liquid in dissipating heat.

[0060] Furthermore, the segmented filter winding uses 8 layers of F-grade enameled wire, and each phase winding is divided into four groups: A1 / A2 / B1 / B2. VITROVAC6025 nanocrystalline magnetic rings 6 are inserted between the groups. The slot wedges are laser-welded to form a continuous magnetic conductive path. A copper-nickel shielding mesh is added to the 8 slots of the stator. When THD>5%, the bias current of the nanocrystalline magnetic rings 6 is increased by adjusting the IGBT switching frequency.

[0061] Start the micro pump 30 to circulate at 0.5L / min for 5 minutes to make the initial temperature of rotor 15 ≤35℃, start phase change cooling, increase the flow rate to 3L / min, and allow the fluorinated liquid to vaporize in the spiral groove 16. When the temperature of rotor (15) >80℃, activate the emergency water cooling module. The emergency water cooling module is a copper tube heat exchanger connected to the outside through a pipe.

[0062] An acoustic emission sensor is fixedly installed at the bottom of the bearing housing. The piezoelectric sensor 21 detects the vibration acceleration of the bearing and extracts the characteristic frequency of 0.5-2kHz through FFT analysis. The fuzzy control module 22 outputs a viscosity adjustment command based on the spectrum characteristics: when vibrating at low frequency, the viscosity of the magnetorheological fluid is increased to 80 Pa·s and the oil film thickness is compressed to 80 μm; when vibrating at high frequency, the viscosity is reduced to 20 Pa·s and the oil film thickness is increased to 150 μm.

[0063] Please see Figure 1 , Figure 3 and Figure 5One embodiment of the present invention provides a high-precision variable frequency speed-regulating asynchronous motor for elevators. The annular hydraulic chamber 19 is filled with magnetorheological fluid, the viscosity of which is adaptive. The oil film thickness is controlled between 50-200 μm by a servo valve 20. The piezoelectric ceramic vibration sensor 21 has a sensitivity of 0.01 μm. The permeability of the nanocrystalline filter magnetic ring 6 is μ=1.2×105. Each phase winding is divided into four groups: A1, A2, B1, and B2. The windings are sequentially embedded in the slots of the stator 8.

[0064] The fluorinated liquid circulation system includes a storage tank 29, a micro pump 30, and a condenser 31. The storage tank 29 is connected to the micro pump 30, which is connected to a hollow cooling pipe 17 via a pipeline. The hollow cooling pipe 17 is connected to a spiral cooling tank 16 via a pipeline. The spiral cooling tank 16 is connected to the condenser 31 via a pipeline. The condenser 31 is connected to the storage tank 29 via a pipeline. The condenser 31 integrates a semiconductor cooling chip 34. The fluorinated liquid has a boiling point of 56℃, a latent heat of 350kJ / kg, and the circulation flow rate is adjustable from 0.5-5L / min by the micro pump 30.

[0065] Furthermore, the stator 8 is fixed to the bottom of the inner wall of the motor housing 3 using mounting bolts, the inner ring of the rotor 15 is fitted onto the outer ring of the shaft 4, the inner ring of the double row angular contact bearing 18 is fitted into the journal of the shaft 4, and the two ends of the shaft 4 are supported on the bearing seats of the motor housing 3 by the double row angular contact bearing 18.

[0066] Connect the power supply and perform a no-load test run on the motor. Observe whether the motor rotation is smooth and whether there is any abnormal noise or vibration. Use a vibration tester to measure the motor vibration amplitude. At a speed of 1000 r / min, the vibration amplitude should not exceed 0.05 mm. Install temperature sensors on the stator windings, rotor, and bearing sidewalls. After running the motor for 30 minutes, use a temperature monitor to monitor the temperature of each part. Under normal operation, the stator winding temperature should not exceed 120℃, the rotor temperature should not exceed 100℃, and the bearing temperature should not exceed 80℃. Run the motor and check whether the signal transmission of the main encoder 1 and auxiliary encoder 2 is normal. The DSP control board 11 processes the signals. To verify the accuracy of the calculation, a scenario was set where the main encoder 1 signal was lost for 3ms with a deviation of 0.5%. This was used to verify whether the DSP control board 11 could switch to the auxiliary encoder 2 within 10ms and accurately compensate for the phase difference. The fluorinated liquid circulation system was run, and the flow rate and pressure of the fluorinated liquid were checked using a flow meter and a pressure gauge. The flow rate should be within the range of 0.5-5L / min, and the pressure should be between 0.2-0.4MPa. The circulation system was checked for leaks. The motor was run with load rates of 30%, 50%, and 70% respectively, and the temperature of various parts of the motor was measured using an infrared thermometer to evaluate the heat dissipation effect of the cooling system.

[0067] Please see Figure 1 , Figure 2 and Figure 5This invention provides an embodiment of a high-precision variable frequency speed-regulating asynchronous motor for elevators. The method of use includes the following steps: S1, the main encoder 1 detects the front end angle position of the rotating shaft 4, and the auxiliary encoder 2 detects the end position. The main encoder 1 serves as a reference, and the auxiliary encoder 2 automatically compensates for the phase difference. The DSP control board 11 performs real-time differential calculations on the detection signals of the main encoder 1 and the auxiliary encoder 2 to compensate for the torsional deformation of the rotating shaft 4. When the signal loss of the main encoder 1 is ≥3ms / deviation >0.5%, the DSP control board 11 switches to the auxiliary encoder 2; S2, the DSP control board 11 communicates with the auxiliary encoder 2 via the CAN bus interface 2. 4. Communicate with the elevator control system to detect the communication status of the main encoder 1, auxiliary encoder 2, fuzzy control module 22 and servo valve 20. Inject 99.99% pure argon into the sealed interface of the motor housing 3 to replace the internal air until the oxygen content is <0.1%. S3. When the output of the frequency converter passes through the segmented winding of the stator 8, harmonics above 5kHz are absorbed by the nanocrystalline magnetic ring 6. S4. The fluorinated liquid flows from the storage tank 29 through the micro pump 30 along the hollow cooling pipe 17 and the spiral cooling groove 16. After absorbing heat, the fluorinated liquid flows back to the condenser 31 to form an initial cycle. It is cooled by the action of the semiconductor cooling chip 34 and then flows back to the storage tank 29.

[0068] S11. Winding A1, as the starting end of phase A winding, is responsible for receiving and transmitting the initial current signal. Winding A1 is in direct contact with filter ring 1. The signal processed by filter ring 1 is transmitted to winding A2. Winding A2 is connected to phase B starting segment B1. B1 is in contact with filter ring 2. The signal processed by filter ring 2 is transmitted to winding B2. S12. Piezoelectric ceramic sensor 21 detects vibration signal and transmits it to DSP control board 11. DSP control board 11 calculates compensation amount and feeds it back to servo valve 20. At the same time, fuzzy control module 22 outputs PWM signal to servo valve 20. Servo valve 20 adjusts the viscosity of magnetorheological fluid to dynamically balance the eccentricity of rotor 15. Fuzzy control module 22 performs fuzzification processing on load torque observer signal according to fuzzy control rules. After fuzzy inference and defuzzification processing, it outputs space vector modulation command. S13. Piezoelectric ceramic vibration sensor 21 detects abnormal vibration signal and triggers emergency stop program. DSP control board 11 cuts off motor power. DSP control board 11 combines feedback information from main encoder 1, auxiliary encoder 2 and piezoelectric ceramic vibration sensor 21 to locate fault point.

[0069] Furthermore, after the motor starts, the main encoder 1 detects the front end angle position of the shaft 4 in real time, and the auxiliary encoder 2 detects the end position. During motor operation, the signals of the main encoder 1 and the auxiliary encoder 2 are collected every 1ms. At the same time, a signal monitoring program is set to monitor the signal of the main encoder 1 in real time. When the signal loss time of the main encoder 1 reaches 3ms or the deviation is greater than 0.5%, the DSP control board 11 immediately issues a switching command, completes the switching to the auxiliary encoder 2 operation within 5ms, and adjusts the control parameters.

[0070] Before the motor starts running, the DSP control board 11 sends a communication request to the elevator control system via the CAN bus interface 24. After receiving the request, the elevator control system returns an acknowledgment message. Every 5 seconds, the DSP control board 11 polls and checks the communication status of the main encoder 1, auxiliary encoder 2, fuzzy control module 22, and servo valve 20. If an abnormal communication is detected, the faulty equipment information will be displayed on the screen, and the fault time will be recorded. Before the motor starts running, argon gas is injected through the sealed interface of the motor housing 3 at a flow rate of 0.5 L / min for 30 minutes. The micro pump 30 is started to pump the fluorinated liquid from the storage tank 29 into the hollow cooling pipe 17 at an initial flow rate of 1 L / min, and then into the screw... The fluorinated liquid, after absorbing heat, flows back to the condenser 31 in the vortex cooling tank 16. The semiconductor cooling chip 34 starts working, cooling the fluorinated liquid to 28°C before it flows back to the storage tank 29, completing one cycle. The piezoelectric ceramic vibration sensor 21 continuously monitors the vibration signal of the motor. When an abnormal vibration signal is detected, the DSP control board 11 cuts off the motor power supply within 5ms after receiving the trigger signal. At the same time, combined with the feedback information from the main encoder 1, the auxiliary encoder 2, and the piezoelectric ceramic vibration sensor 21, the fault point is located through the fault diagnosis algorithm. If the signal of the main encoder 1 is abnormal and the vibration signal exceeds the normal range, it is determined that the connection between the shaft 4 and the encoder is faulty; if only the vibration signal is abnormal, it is a bearing fault or the rotor 15 is unbalanced.

[0071] Working principle: The main encoder 1 and the auxiliary encoder 2 detect the front and rear end angle positions of the rotating shaft 4 respectively. The main encoder 1 serves as the reference, and the auxiliary encoder 2 automatically compensates for the phase difference. The signals of the two are differentially calculated in real time by the DSP control board 11 to compensate for the torsional deformation of the rotating shaft 4. When the signal of the main encoder 1 is abnormal, it switches to the auxiliary encoder 2 in time. When the motor is working, the current output by the frequency converter passes through the stator segmented winding. Harmonics above 5kHz are absorbed by the nanocrystalline filter magnetic ring 6. At the same time, the fuzzy control module 22 receives the load torque observer signal, and outputs the space vector modulation command after fuzzification and other processing. The fluorinated liquid absorbs heat from the storage tank 29 through the micro pump 30, along the hollow cooling pipe 17 and the spiral cooling groove 16, and then flows back to the condenser 31. After being cooled by the semiconductor cooling chip 34, it returns to the storage tank 29 to form a cycle. When the load rate is >70%, the wave-shaped heat dissipation fins 26 assist in heat dissipation.

[0072] The piezoelectric ceramic vibration sensor 21 detects vibration signals and transmits them to the DSP control board 11. The calculated compensation amount is fed back to the servo valve 20. The fuzzy control module 22 also outputs PWM signals to the servo valve 20 to adjust the viscosity of the magnetorheological fluid to dynamically balance the rotor eccentricity. If abnormal vibration is detected, an emergency stop program is triggered to cut off the power and locate the fault point. The motor communicates with the elevator control system through the CAN bus interface 24. High-purity argon gas is injected into the motor housing. The inner layer is equipped with a copper mesh shielding layer 35, and the outer layer is covered with ferrite absorbing material.

[0073] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A high-precision variable frequency speed-regulating asynchronous motor for elevators, characterized in that: It includes a dual-redundant coding system and a motor housing (3). The dual-redundant coding system is located inside the motor housing (3). A stator (8) is fixedly installed at the bottom of the inner wall of the motor housing (3). The dual-redundant encoding system includes a main encoder (1), an auxiliary encoder (2), and a segmented filter winding. A rotating shaft (4) is fixedly installed on the front end of the outer wall of the main encoder (1). The rear end of the outer wall of the rotating shaft (4) is connected to the auxiliary encoder (2) through a flexible coupling (5). The main encoder (1) is fixed to the front end cover (9) through a flange (7). The signal line of the main encoder (1) is connected to the DSP control board (11) through a shielded cable (10). The segmented filter winding is integrated inside the stator (8). Each phase winding of the stator (8) is divided into 4 groups. A nanocrystalline filter magnetic ring (6) is inserted between each group of the stator (8). The slot wedge inside the stator (8) is made of Fe-Si-B amorphous alloy.

2. The high-precision variable frequency speed-regulating asynchronous motor for elevators according to claim 1, characterized in that: A vibration damping base (12) is fixedly installed at the bottom of the outer wall of the motor housing (3), a lower protective housing (13) is fixedly installed at the bottom of the outer wall of the vibration damping base (12), and an upper protective housing (14) is fixedly installed at the top of the outer wall of the lower protective housing (13).

3. The high-precision variable frequency speed-regulating asynchronous motor for elevators according to claim 1, characterized in that: The motor housing (3) is equipped with a stator (8), a rotor (15), a double-row angular contact bearing (18), and a shaft (4) in sequence. The stator (8) is fixedly installed at the bottom of the inner wall of the motor housing (3). The inner ring of the rotor (15) is fitted onto the outer ring of the shaft (4). The inner ring of the double-row angular contact bearing (18) is fitted into the journal of the shaft (4). The two ends of the shaft (4) are supported on the bearing seats of the motor housing (3) by the double-row angular contact bearing (18). A DSP control board (11) is fixedly installed on the inner wall of the rear end cover of the motor housing (3). The DSP control board (11) is connected to the main encoder (1) and the auxiliary encoder (2) via a data cable.

4. A high-precision variable frequency speed-regulating asynchronous motor for elevators according to claim 3, characterized in that: The rotor (15) has 36 spiral cooling grooves (16) inside its iron core, and a hollow cooling pipe (17) is provided inside the shaft (4). The hollow cooling pipe (17) is connected to the external fluorinated liquid circulation system. The outer wall of the motor housing (3) is fixedly equipped with wave-shaped heat dissipation fins (26), and a PTC heating film (27) is embedded inside the wave-shaped heat dissipation fins (26). The surface of the wave-shaped heat dissipation fins (26) is coated with an aluminum nitride thermal conductive coating (28). The flexible coupling (5) is connected to the rotating shaft (4) by a key. The input shaft of the auxiliary encoder (2) is connected to the output shaft of the flexible coupling (5). The bottom of the outer wall of the flexible coupling (5) is provided with a mounting bracket (32). The mounting bracket (32) is provided with a pre-tightening spring (33). The flexible coupling (5) is provided with a titanium alloy bellows. The axial compensation of the titanium alloy bellows is ±0.5mm, and the radial deflection angle is ±0.1°.

5. A high-precision variable frequency speed-regulating asynchronous motor for elevators according to claim 3, characterized in that: The outer ring of the double-row angular contact bearing (18) has an annular hydraulic chamber (19), which is connected to a servo valve (20) and a piezoelectric ceramic vibration sensor (21). The DSP control board (11) integrates a fuzzy control module (22), which receives load torque observer signals and outputs space vector modulation commands. The inner layer of the motor housing (3) is provided with a copper mesh shielding layer (35), and the outer layer is covered with ferrite absorbing material. The DSP control board (11) integrates a CAN bus interface (24). The CAN bus interface (24) is connected to the main encoder (1) and the auxiliary encoder (2) simultaneously through differential signal lines (25).

6. A high-precision variable frequency speed-regulating asynchronous motor for elevators according to claim 4, characterized in that: The spiral cooling groove (16) has a lead angle of 55° and a depth of 3mm. It is connected to the hollow cooling pipe (17) of the rotating shaft (4) through a radial diversion hole (23). The spiral cooling groove (16) and the hollow cooling pipe (17) form a spiral-axial composite cooling path.

7. A high-precision variable frequency speed-regulating asynchronous motor for elevators according to claim 5, characterized in that: The annular hydraulic chamber (19) is filled with magnetorheological fluid. The viscosity of the magnetorheological fluid is adaptive. The oil film thickness is controlled at 50-200μm by a servo valve (20). The piezoelectric ceramic vibration sensor (21) has a sensitivity of 0.01μm. The permeability μ of the nanocrystalline filter magnetic ring (6) is 1.2 × 10⁻⁶. 5 Each phase winding is divided into four groups: A1, A2, B1, and B2. The windings are sequentially embedded in the stator slot (8).

8. A high-precision variable frequency speed-regulating asynchronous motor for elevators according to claim 4, characterized in that: The fluorinated liquid circulation system includes a storage tank (29), a micro pump (30), and a condenser (31). The storage tank (29) is connected to the micro pump (30). The micro pump (30) is connected to a hollow cooling pipe (17) through a pipe. The hollow cooling pipe (17) is connected to a spiral cooling tank (16). The spiral cooling tank (16) is connected to the condenser (31) through a pipe. The condenser (31) is connected to the storage tank (29) through a pipe. The condenser (31) integrates a semiconductor cooling chip (34) inside. The fluorinated liquid has a boiling point of 56℃ and a latent heat of 350kJ / kg. The circulation flow rate can be adjusted from 0.5 to 5L / min by a micro pump (30).

9. A method of using a high-precision variable frequency speed-regulating asynchronous motor for elevators, applicable to the high-precision variable frequency speed-regulating asynchronous motor for elevators as described in any one of claims 1-8, characterized in that: The method of use includes the following steps: S1. The main encoder (1) detects the front corner position of the rotating shaft (4), and the auxiliary encoder (2) detects the end position. The main encoder (1) serves as the reference, and the auxiliary encoder (2) automatically compensates for the phase difference. The DSP control board (11) performs real-time differential calculation on the detection signals of the main encoder (1) and the auxiliary encoder (2) to compensate for the torsional deformation of the rotating shaft (4). When the signal loss of the main encoder (1) is ≥3ms / deviation>0.5%, the DSP control board (11) switches to the auxiliary encoder (2). S2, DSP control board (11) communicates with elevator control system through CAN bus interface (24) to detect the communication status of main encoder (1), auxiliary encoder (2), fuzzy control module (22) and servo valve (20). 99.99% pure argon gas is injected into the sealed interface of motor housing (3) to replace the internal air to oxygen content <0.1%; S3. When the output of the frequency converter passes through the segmented winding of the stator (8), the harmonics above 5kHz are absorbed by the nanocrystalline magnetic ring (6). S4. Fluorinated liquid flows from the storage tank (29) through the micro pump (30) along the hollow cooling pipe (17) and spiral cooling tank (16). After absorbing heat, the fluorinated liquid flows back to the condenser (31) to form an initial cycle. It is cooled by the semiconductor cooling chip (34) and then flows back to the storage tank (29).

10. The method of using a high-precision variable frequency speed-regulating asynchronous motor for elevators according to claim 9, characterized in that: The method of use also includes the following steps: S11. Winding A1 serves as the starting end of the A-phase winding and is responsible for receiving and transmitting the initial current signal. Winding A1 is in direct contact with filter ring 1. The signal processed by filter ring 1 is transmitted to winding A2. Winding A2 is connected to the starting segment B1 of phase B. B1 is in contact with filter ring 2. The signal processed by filter ring 2 is transmitted to winding B2. S12, the piezoelectric ceramic sensor (21) detects the vibration signal and transmits it to the DSP control board (11). The DSP control board (11) calculates the compensation amount and feeds it back to the servo valve (20). At the same time, the fuzzy control module (22) outputs the PWM signal to the servo valve (20). The servo valve (20) adjusts the viscosity of the magnetorheological fluid to dynamically balance the eccentricity of the rotor (15). The fuzzy control module (22) performs fuzzification processing on the load torque observer signal according to the fuzzy control rules. After fuzzy inference and defuzzification processing, it outputs the space vector modulation command. S13, the piezoelectric ceramic vibration sensor (21) detects an abnormal vibration signal and triggers an emergency stop program. The DSP control board (11) cuts off the motor power supply. The DSP control board (11) combines the feedback information from the main encoder (1), the auxiliary encoder (2) and the piezoelectric ceramic vibration sensor (21) to locate the fault point. S41. After the fluorinated liquid absorbs the heat of the rotor (15) in the spiral cooling tank (16), it partially vaporizes. When the load rate is >70%, the wave-shaped heat dissipation fins (26) assist the fluorinated liquid in dissipating heat.

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