A method for evaluating the running stability of a high-speed shaft system of a large-torque control moment gyroscope

Abstract

The present application relates to a kind of high-speed shafting running stability evaluation method of large torque control moment gyro, it is related to testing field, comprising the following steps: the initial high-speed shafting is recorded by photographing microscope, and the surface state of part and bearing is recorded, high-speed shafting is installed, and the difference between the natural frequency and target frequency of debugging combined system is less than ±5% between target frequency;Drive high-speed shafting rotation, after speed stabilizes, drive swing turntable swing, monitor the current, temperature, speed curve and the situation of shafting noise in the running-in period of high-speed shafting in the running-in process on testing device, replace part and retest when abnormal;When to run-in period is qualified, high-speed shafting is removed and disassembled, and the surface of part is observed by photographing microscope, and retest is replaced when abnormal, until running-in process and observation result all meet requirements, the present application has the advantages that the precision of running stability evaluation examination is improved.

Description

Technical Field

[0001] This invention relates to the field of testing technology, and in particular to a method for evaluating the operational stability of a high-speed shaft system of a high-torque control torque gyroscope. Background Technology

[0002] The ControlMoment GY25100303roscope (CMG) outputs the control torque required for attitude control of large spacecraft such as space stations by changing the direction of the angular momentum vector of the high-speed shaft system. The high-speed shaft system is the core component of the high-torque CMG for acquiring angular momentum, operating continuously at high speeds (typically above 6000 r / min). During spacecraft attitude adjustments, it also faces the challenge of large fluctuations in load (maximum torque not less than 200 Nm). The coupling effect between the CMG high-speed shaft system support frame and the spacecraft interface affects the support and vibration characteristics of the high-speed shaft system. For structures like the high-torque CMG, the high-speed bearings operate under high loads during torque output. The impact of structural and modal changes on the bearing load distribution evolution is more significant than in CMGs with medium or small torques, affecting the long-term stability of the CMG high-speed shaft system in orbit.

[0003] Therefore, during the ground phase, it is necessary to simulate the operating conditions of the high-speed shaft system on the spacecraft and test the stability of the shaft system operation. Obtaining simulated operating conditions that closely resemble the on-orbit operating conditions is crucial and also a challenge, especially for the CMG high-speed shaft system under high torque output conditions.

[0004] Currently, the main focus is on reproducing the on-orbit vacuum and alternating high and low temperature environments, testing data such as drive current (reflecting shaft resistance torque), temperature rise, and vibration during the operation of high-speed shaft systems, and examining the stability evaluation methods for the wear state of bearing parts surfaces, especially cage surfaces, after the test, in order to expose weak links in advance and ensure the overall performance and service life of the spacecraft.

[0005] Application CN119000079A discloses a method for testing and evaluating the performance and stability of shaft bearings under conditions such as simulated bearing temperature and axial and radial load variations. The currently retrieved patent methods have the following problems:

[0006] (1) The structure of the test shaft system mounting interface is fixed, and the simulation of the test shaft system working conditions does not take into account the stiffness and damping state of the actual working interface. According to the existing invention method, the operating state will have errors under different mounting interfaces in actual application.

[0007] (2) The application of constant force or simple, small-range variation of the axial and radial forces of the shaft system is a large deviation from the load mode of large-torque CMG acceleration and deceleration with large sinusoidal variation, resulting in large measurement and evaluation errors.

[0008] (3) It cannot accurately reproduce the operating conditions when the high torque output of the simulated high-speed shaft system is applied, and the effectiveness of the evaluation of the operating status is insufficient. It is difficult to avoid the product from operating instably in orbit, which will have an adverse effect on the satellite pointing accuracy and imaging accuracy.

[0009] Therefore, to address the above shortcomings, it is necessary to provide a method for evaluating the operational stability of a high-torque control torque gyroscope high-speed shaft system. Summary of the Invention

[0010] (a) Technical problems to be solved

[0011] The technical problem to be solved by this invention is the difficulty in accurately simulating the operating conditions when evaluating the stability of shaft system operation.

[0012] (II) Technical Solution

[0013] To address the aforementioned technical problems, this invention provides a method for evaluating the operational stability of a high-speed shaft system with high-torque control torque gyroscope, comprising the following steps:

[0014] Ⅰ. Assemble the high-speed shaft system and record the surface condition of the initial high-speed shaft system parts and bearings using a photomicroscope;

[0015] II. Install the high-speed shaft system onto the upper connecting plate of the test device, and adjust the difference between the natural frequency and the target frequency of the combined system to be less than ±5% of the target frequency;

[0016] Ⅲ. Drive the high-speed shaft system to rotate. After the speed stabilizes, drive the swing turntable to swing. Monitor the current, temperature, speed curve and shaft noise of the high-speed shaft system during the running-in period on the test device. If any abnormality is found, replace the parts and repeat the experiment.

[0017] IV. Repeat the above steps until the monitoring curve is stable and without fluctuations during the running-in period, and the shaft system is free of noise; then remove and disassemble the high-speed shaft system, observe the surface of the parts using a photographic microscope, and if wear is found, replace the parts and continue to repeat the above steps to conduct the experiment until the running-in process and observation results meet the requirements.

[0018] As a further explanation of the present invention, preferably, the natural frequency of the system satisfies:

[0019]

[0020] in,

[0021] f n This is the system's natural frequency;

[0022] k is the stiffness of the system;

[0023] m is the mass of the system;

[0024] ζ is the damping ratio of the system.

[0025] As a further explanation of the present invention, preferably, the combined system is a combination of a test device and a high-speed shaft system, and the target frequency is the natural frequency of the high-speed shaft system located at the star mounting interface.

[0026] As a further explanation of the present invention, preferably, the natural frequency value of the high-speed shaft system located at the satellite mounting interface is obtained based on the whole satellite test data. The natural frequency of the combined system is tested through the exciter and the acceleration sensor in the combined module. Based on the current difference between the two, the parameters of the variable stiffness spring and the variable damper are adjusted so that the difference between the two is less than ±5% of the target frequency.

[0027] As a further explanation of the present invention, preferably, the running-in process is determined to be unstable when the shaft system operating resistance torque fluctuates, the shaft temperature rises, the rotation speed fluctuates, or the rotating parts produce scraping noise; otherwise, it is considered stable.

[0028] As a further explanation of the present invention, preferably, after the running-in process is determined to be unstable, the high-speed shaft system is removed and disassembled, and the surface of the high-speed shaft system parts is observed through a 40x microscope. If the surface of the high-speed shaft system parts shows wear, abnormal scratches on the bearing rings and balls, or abnormally increased wear on the surface of the bearing cage, then the shaft system parts or bearings need to be replaced and the experiment is repeated.

[0029] As a further explanation of the present invention, preferably, after the running-in process is determined to be stable, the high-speed shaft system is removed and disassembled, and the surface of the high-speed shaft system parts is observed through a 40x microscope. If the surface of the high-speed shaft system parts shows wear, abnormal scratches on the bearing rings and balls, or wear on the surface of the bearing cage exceeds the threshold, then the shaft system parts or bearings need to be replaced and the experiment is repeated.

[0030] As a further explanation of the present invention, preferably, the swing angular velocity and the change mode of the swing turntable are determined according to the frame motion mode when the large torque is output.

[0031] As a further explanation of the present invention, preferably, if the oscillation mode is sinusoidal, then:

[0032] M max =Iw1w2

[0033] in,

[0034] M max This is the maximum output torque;

[0035] I represents the moment of inertia of the high-speed shaft system;

[0036] w1 is the rotational speed of the high-speed shaft system under actual operating conditions;

[0037] w2 is the maximum angular velocity of the high-speed shaft system under sinusoidal oscillation.

[0038] As a further explanation of the present invention, preferably, the combined module includes a display module to display the current inherent frequency of the system.

[0039] (III) Beneficial Effects

[0040] The above-described technical solution of the present invention has the following advantages:

[0041] 1. This invention employs a spring with adjustable system stiffness and a variable damper with adjustable system damping to accurately match the natural frequency of the high-speed shaft system's on-orbit installation interface, thereby accurately and directly simulating the installation state of the high-torque CMG shaft system on the spacecraft.

[0042] 2. This invention utilizes rotor drive and a swing turntable to accurately reproduce the stress state of the CMG high-speed shaft system on the ground when it is under high torque output on the rail. Combined with the simulation of the on-rail installation state, it overcomes the defect of traditional methods in evaluating test conditions being detached from reality, and improves the accuracy of operational stability evaluation and assessment.

[0043] 3. This invention, by testing performance data during the operation of a high-speed rotor and analyzing the condition of parts, can accurately evaluate the operational stability of the shaft system and eliminate defective parts that may cause instability and potential parts that may cause operational instability in advance. It can be applied to the evaluation of the operational stability of various high-load spatial shaft systems such as high-torque flywheels and control torque gyroscopes, avoiding operational instability during long-term on-orbit service that could cause damage, ultimately reducing product performance, reliability, and lifespan.

[0044] 4. The evaluation method provided by this invention is simple in principle and convenient and reliable in testing. It can be used for product development or developed into a dedicated testing instrument. Attached Figure Description

[0045] Figure 1 This is a simplified diagram of the evaluation device of the present invention;

[0046] Figure 2 This is a flowchart of the evaluation process of the present invention;

[0047] Figure 3 It is a current curve diagram showing the transition of high-speed shaft current from stable to unstable.

[0048] Figure 4 It is an outline drawing of a shaft cage with good stability;

[0049] Figure 5 The shape and microscopic image of the wear-resistant cage with insufficient stability.

[0050] In the diagram: 1. Test device; 11. Upper connecting plate; 12. Variable stiffness spring; 13. Variable damper; 14. Exciter; 15. Combination module; 16. Swinging turntable; 17. Connecting base plate; 2. High-speed shaft system. Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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, 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.

[0052] A method for evaluating the operational stability of a high-speed shaft system of a torque-controlled gyroscope involves a testing device 1, such as... Figure 1 As shown, the system includes an upper connecting plate 11, a variable stiffness spring 12, a variable damper 13, an exciter 14, a combination module 15, a swing turntable 16, and a connecting base plate 17. The swing turntable 16 is mounted on the connecting base plate 17, the exciter 14 is mounted inside the swing turntable 16, the variable stiffness spring 12 and the variable damper 13 are both arranged on the swing turntable 16, and the upper connecting plate 11 is mounted on the variable stiffness spring 12 and the variable damper 13. The combination module 15 contains an acceleration sensor and a natural frequency display module, and the combination module 15 is installed on the upper connecting plate 11.

[0053] like Figure 2 As shown, the high-speed shaft system operation stability evaluation method of the present invention includes the following steps:

[0054] 1. Assemble the CMG high-speed shaft system 2 according to the drawings and procedures, and record the initial shaft system parts and bearing surface conditions using a 40x photomicroscope.

[0055] 2. Install the high-speed shaft system 2 on the upper connecting plate 11 of the operational stability testing device 1. Obtain the natural frequency value of the high-speed shaft system mounting interface based on the whole-satellite test data. Test the natural frequency of the CMG high-speed shaft system-evaluation device combined system using the acceleration sensors in the exciter 14 and the combined module 15. Adjust the parameters of the variable stiffness spring 12 and the variable damper 13 based on the difference between the two values, and set the natural frequency f of the system by changing the system stiffness and damping ratio. n The frequency setting follows the formula:

[0056]

[0057] in,

[0058] k is the stiffness of the system;

[0059] m is the mass of the system;

[0060] ζ is the damping ratio of the system.

[0061] The system's natural frequency f n Measured values ​​may contain errors due to differences in the structure of different products. Fine-tuning is performed through repeated testing until the difference between the system's natural frequency and the target frequency is less than ±5% of the target frequency.

[0062] 3. The high-speed shaft system 2 is rotated at the actual operating speed w1 using a drive device. After the speed stabilizes, the turntable is driven to swing. The swing angular velocity and its variation are determined according to the frame motion mode when the maximum torque is output. For example, if the swing mode is sinusoidal, the maximum angular velocity is w2, and the swing period is t, then operating in this mode, when the moment of inertia of the high-speed shaft system is I, the maximum output torque is:

[0063] M max =Iw1w2

[0064] 4. By monitoring the current, temperature, speed curves, and shaft noise of the high-speed shaft system 2 during the running-in period T on the test device 1, the operational stability of the CMG high-speed shaft system 1 during the running-in process is evaluated. For example... Figure 3 As shown, the evaluation criteria are: when the high-speed shaft system 2 has insufficient operational stability, the possible manifestations are as follows:

[0065] a. Fluctuations occur in the operating resistance torque of shaft system 1;

[0066] b. Shaft temperature rises;

[0067] c. The rotational speed fluctuates;

[0068] d. Scratching noise from rotating parts.

[0069] If the monitoring curve exhibits the above abnormalities within the test cycle T, the test must be stopped, the high-speed shaft system 2 removed from the test device 1, and the components of the high-speed shaft system 2 disassembled. The surface of the components should be observed using a 40x microscope. Figure 5 As shown, if wear appears on the surface of the high-speed shaft system 2 parts, or if there are abnormal scratches on the bearing races and balls, or abnormally increased wear on the surface of the bearing cage, then the shaft system parts or bearings need to be replaced.

[0070] 5. Repeat steps 1-4 until the monitoring curve remains stable and without fluctuations during the running-in period, and high-speed shaft 2 is noiseless. After the running-in period, remove high-speed shaft 2 from test device 1 and disassemble the parts. Figure 5As shown, the surface of the parts is observed using a 40x microscope. If wear is found on the surface of the high-speed shaft system 2 parts, abnormal scratches are found on the bearing races and balls, or the wear on the bearing cage surface exceeds the threshold, it indicates that the shaft system has a potential for unstable operation and the shaft system parts or bearings need to be replaced.

[0071] 6. Repeat steps 1-5 until the high-speed shaft 2 speed, current, temperature rise, and noise data meet the requirements during the running-in process, and after the running-in is completed, if... Figure 4 As shown, disassembly and observation simultaneously meet the requirements, and the high-speed shaft system 2 passes the operational stability evaluation.

[0072] In summary, this invention employs methods to simulate the installation interface structure by adjusting the stiffness and damping of the high-torque CMG high-speed shaft system support platform, and to simulate the high-torque output condition by adjusting the swing mode of the support platform. This is achieved by adjusting the stiffness of the installation platform using a variable stiffness spring 12 under the connecting plate 11 on the platform mounting surface of the high-speed shaft system 2; adjusting the damping of the support platform using a variable damper 13 under the upper connecting plate 11, ensuring that the natural frequency of the entire system is the same as the natural frequency tested on the spacecraft when the high-speed shaft system 2 is installed on the platform; and simulating the high-torque output condition by using the swing turntable 16 of the support platform, which causes the high-speed rotating shaft system to swing according to the swing angular velocity and period during torque output. This allows for the evaluation of the operational stability of the high-speed shaft system 2 during its running-in state. In other words, this invention creatively uses methods to simulate the installation interface by adjusting the stiffness and damping of the running-in platform structure, and simulates the shaft system load condition during high-torque output by adjusting the swing mode of the installation turntable. This solves the problem of accurately simulating the operating conditions during shaft system operational stability evaluation, ensuring that the CMG high-speed shaft system that passes the evaluation can maintain long-term stable operation in orbit.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for evaluating the operational stability of a high-speed shaft system of a high-torque controlled torque gyroscope, characterized in that: Includes the following steps: Ⅰ. Assemble the high-speed shaft system (2) and record the surface condition of the parts and bearings of the initial high-speed shaft system (2) using a photographic microscope; II. Install the high-speed shaft system (2) onto the upper connecting plate (11) of the test device (1), and adjust the difference between the natural frequency and the target frequency of the combined system to be less than ±5% of the target frequency; Ⅲ. Drive the high-speed shaft system (2) to rotate. After the speed stabilizes, drive the swing turntable (16) to swing. The swing angular velocity and change mode of the swing turntable (16) are determined according to the frame motion mode when the high torque is output. Monitor the current, temperature, speed curve and shaft noise of the high-speed shaft system (2) during the running-in period on the test device (1). If any abnormality occurs, replace the parts and repeat the experiment. IV. Repeat the above steps until the monitoring curve is stable and without fluctuations during the running-in period, and the shaft system is free of noise; then remove and disassemble the high-speed shaft system, and observe the surface of the parts using a photographic microscope. If wear is found, replace the parts and continue to repeat the above steps to conduct the experiment until the running-in process and observation results meet the requirements; when the shaft system operating resistance torque fluctuates, the shaft temperature rises, the speed fluctuates, or the rotating parts produce scraping noise, the running-in process is considered unstable, otherwise it is stable.

2. The method for evaluating the operational stability of a high-speed shaft system with high-torque control torque gyroscope according to claim 1, characterized in that: The system's natural frequency satisfies: in, This is the system's natural frequency; The stiffness of the system; For the quality of the system; Let be the damping ratio of the system.

3. The method for evaluating the operational stability of a high-speed shaft system with high-torque control torque gyroscope according to claim 2, characterized in that: The combined system is a combination of the test device (1) and the high-speed shaft system (2), and the target frequency is the natural frequency of the high-speed shaft system (2) located at the star mounting interface.

4. The method for evaluating the operational stability of a high-speed shaft system of a high-torque controlled torque gyroscope according to claim 3, characterized in that: The natural frequency value of the high-speed shaft system (2) located at the star installation interface is obtained based on the whole satellite test data. The natural frequency of the combined system is tested by the acceleration sensor in the exciter (14) and the combined module (15). Based on the current difference between the two, the parameters of the variable stiffness spring (12) and the variable damper (13) are adjusted so that the difference between the two is less than ±5% of the target frequency.

5. The method for evaluating the operational stability of a high-speed shaft system with high-torque control torque gyroscope according to claim 4, characterized in that: After the running-in process is determined to be unstable, the high-speed shaft system (2) is removed and disassembled. The surface of the high-speed shaft system (2) parts is observed through a 40x microscope. If the surface of the high-speed shaft system (2) parts is worn, the bearing rings and balls have abnormal scratches, or the surface of the bearing cage has abnormally increased wear, then the shaft system parts or bearings need to be replaced before the experiment is conducted.

6. The method for evaluating the operational stability of a high-speed shaft system with high-torque control torque gyroscope according to claim 1, characterized in that: After the running-in process is determined to be stable, the high-speed shaft system (2) is removed and disassembled. The surface of the high-speed shaft system (2) parts is observed through a 40x microscope. If the surface of the high-speed shaft system (2) parts is worn, the bearing rings and balls are scratched abnormally, or the surface wear of the bearing cage is greater than the threshold, the shaft system parts or bearings need to be replaced and the experiment is repeated.

7. The method for evaluating the operational stability of a high-speed shaft system with high-torque control torque gyroscope according to claim 6, characterized in that: If the oscillation pattern is sinusoidal, then: in, This is the maximum output torque; The moment of inertia of the high-speed shaft system (2); The rotational speed of the high-speed shaft system (2) under actual working conditions; The maximum angular velocity of the high-speed shaft system (2) under sinusoidal oscillation is given.

8. The method for evaluating the operational stability of a high-speed shaft system of a high-torque controlled torque gyroscope according to claim 1, characterized in that: The combined module (15) has a display module to display the current inherent frequency of the system.

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