Large generator set modal test detection device and automatic control system and method

Abstract

The present application belongs to the field of generator set production, and discloses a large generator set modal test detection device, an automatic control system and a method. The device part integrates air floatation support and excitation function into one device, realizes double effect of support and excitation force application, improves test precision and test efficiency, and can meet high-precision and high-efficiency test requirements of heavy equipment such as large generator sets. The automatic control system realizes intelligent adjustment of piston height and excitation force through a controller, a proportional control valve, a displacement sensor and a pressure sensor, improves test efficiency and precision, reduces material and labor costs, shortens test cycle, and has high economy and practicability. The present application can simplify device structure, reduce device cost, save labor, improve test precision and test efficiency, realize intelligent control, and has high applicability. The present application is suitable for the electric power construction industry and is used for modal test detection of large generator sets.

Description

Technical Field

[0001] This invention belongs to the field of generator set manufacturing, specifically a large generator set modal testing and detection device and its automated control system and method. Background Technology

[0002] In power construction, modal testing is commonly used to inspect generator sets. Modal testing is a technical means to determine the modal parameters of a structure through vibration testing. Its main purpose is to study the dynamic characteristics of the structure, evaluate the structural strength and reliability of the generator set, facilitate the timely detection and resolution of equipment defects in generator operation, and provide a basis for structural design and optimization in generator set production.

[0003] When conducting modal testing on generator sets, two conditions must be met: first, the generator set must be supported; second, vibration must be applied to the generator set. Traditional methods of supporting and vibrating generator sets include conventional mechanical supports, air-bearing supports, and electromagnetic vibration technology. Because traditional mechanical supports (such as springs or rubber pads) apply additional constraint forces to the object under test, affecting the accuracy of the test results, a combination of air-bearing supports and electromagnetic vibration is often used for modal testing of generator sets.

[0004] However, the combined use of air-bearing supports and electromagnetic vibration has the following drawbacks: First, air-bearing supports require a high-pressure air source and a precision control system, resulting in complex equipment structure, high maintenance costs, and applicability only to testing small components, making direct application to large generator sets difficult. Second, high-end electromagnetic vibration equipment is expensive and has poor adaptability to testing large equipment. Third, air-bearing supports and electromagnetic vibration devices are typically designed as separate units, increasing the difficulty of operation and making it difficult to meet the high-precision, high-efficiency testing requirements of heavy equipment such as large generator sets. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention aims to provide a modal testing device and automated control system and method for large generator sets, in order to meet the high-precision and high-efficiency testing requirements for heavy equipment such as large generator sets, and reduce testing and maintenance costs.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: This invention provides a modal testing device for a large generator set, comprising a support, a cylinder, an air source, a piston, an excitation motor, and a load-bearing plate. The cylinder is fixedly mounted on the support, and the interior of the cylinder is a hollow chamber. The piston includes a load-bearing plate and a piston cylinder fixedly connected together. The piston cylinder is sleeved on the outer wall of the cylinder and airtightly connected to the cylinder. The air source is connected to the hollow chamber of the cylinder through an air supply pipeline and drives the piston to move vertically. The load-bearing plate is sealed and fixed to the top of the piston cylinder. The excitation motor is disposed between the load-bearing plate and the support, and includes a stator and a mover coaxially arranged. The mover is fixedly connected to the load-bearing plate and outputs axial excitation force to drive the load-bearing plate to reciprocate vertically. The stator is fixedly mounted on the support and coaxially sleeved on the outer periphery of the mover.

[0007] As a limitation of the present invention: an airbag ring is provided between the piston and the outer wall of the cylinder body. The airbag ring is sleeved on the outer periphery of the cylinder body. The upper edge of the airbag ring is fixedly connected to the piston through an upper pressure ring, and the lower edge of the airbag ring is fixedly connected to the cylinder body through a lower pressure plate.

[0008] As a further limitation of the present invention: the excitation motor is a linear motor.

[0009] As another limitation of the present invention: at least one row of vertical mounting grooves is provided on the outer wall of the cylinder body, each row of vertical mounting grooves includes multiple vertical mounting grooves arranged circumferentially along the outer wall of the cylinder body, and multiple rolling elements are uniformly embedded in each vertical mounting groove, with the rolling elements exposed outside the vertical mounting groove and rollingly contacting the inner wall of the piston.

[0010] As a further limitation of the present invention: the support is made of high-strength aluminum alloy material.

[0011] The present invention also provides an automated control system, including a controller and a proportional control valve; the proportional control valve is fixed on a support and electrically connected to the controller, and the outlet end of the proportional control valve is connected to an air supply pipeline.

[0012] As a limitation of the present invention, it also includes a displacement sensor and a sensing plate. The sensing plate is fixed on the side of the load-bearing plate facing the support. The displacement sensor is fixed on the support at a position corresponding to the sensing plate. The displacement sensor is electrically connected to the controller. The displacement sensor monitors the piston displacement in real time and feeds it back to the controller.

[0013] As a further limitation of the present invention, it also includes a pressure sensor disposed between the exciter motor and the support, the pressure sensor being electrically connected to the controller to transmit pressure parameters, and the controller being electrically connected to the exciter motor.

[0014] The present invention also provides an automated control method, the method comprising the following steps: S1. Air Float Pressure Setting; Calculate the required air float pressure based on the generator set weight and set the initial value via the controller; S2. Input excitation force parameters; input the target excitation force and frequency, and the controller will automatically match the excitation motor current; S3. Turn on the air supply and controller, and the piston will float to the set height; S4. Vibration test: The controller sends a command, and the excitation motor applies the target excitation force at the input frequency for a certain period of time. S5. Data Acquisition; Record the vibration signals of the generator set using an accelerometer and analyze its modal parameters; S6. Automatic adjustment; if the air flotation pressure fluctuation exceeds the limit during the test, the controller dynamically adjusts the opening of the proportional control valve to maintain stable air flotation pressure; S7. Output the test results.

[0015] As a limitation of the present invention: step S6 further includes an intelligent adjustment stage, which includes the following: Dynamic balance; the displacement sensor monitors the piston height in real time. If a deviation is detected, the controller adjusts the proportional control valve to increase or decrease the air supply to maintain a constant suspension height. Closed-loop control of excitation force: a pressure sensor monitors air flotation pressure fluctuations, and the controller synchronously adjusts the output force of the excitation motor to ensure stable excitation force amplitude.

[0016] By adopting the above technical solution, the beneficial effects achieved by the present invention compared with the prior art are as follows: This invention provides a modal testing device for large generator sets. It utilizes an air source to supply air through an air delivery channel and pipeline into the hollow cavity of the cylinder, causing the piston to suspend and thus lifting the generator set placed on a support plate to the required support height. The overall structure is simple and low-cost. A vibration motor applies vibration force to the support plate to perform modal testing on the generator set, further reducing costs. Air buoyancy allows the generator set to be in a near-free and unconstrained state, reducing the influence of external constraints on the test results and improving the accuracy of modal test results. This device integrates air buoyancy support and vibration functions into one device, simplifying the equipment structure, reducing maintenance costs, and achieving the dual effects of support and vibration force application. It reduces pre-test preparation and in-test procedures, making it more convenient and improving test accuracy and efficiency, meeting the high-precision and high-efficiency testing requirements of heavy equipment such as large generator sets. This invention also provides an automated control system. A displacement sensor monitors the displacement of the load-bearing plate in real time and transmits the displacement signal to a controller. The controller determines the piston's support height. If the weight of the generator set causes a shift, the displacement sensor feeds back to the controller. The controller then adjusts the proportional control valve to increase or decrease the air supply, thereby adjusting the generator set's support height and maintaining a constant suspension height of the load-bearing plate. This ensures precise load-bearing performance and improves testing accuracy. A pressure sensor feeds back the air flotation pressure parameters to the controller. The controller, based on a preset program, determines whether to adjust the frequency and amplitude of the AC power supply to the excitation motor and sends an excitation command to the excitation motor. This controls the excitation motor to apply the target excitation force to the generator set, ensuring the accuracy of the applied excitation force. This system, through the controller, proportional control valve, displacement sensor, and pressure sensor, achieves intelligent adjustment of the piston height and excitation force, improving testing efficiency and accuracy, reducing material and labor costs, and shortening the testing cycle. It is highly economical and practical, and more suitable for modal testing of large generator sets.

[0017] In summary, this invention simplifies equipment structure, reduces equipment costs, saves manpower, improves testing accuracy and efficiency, achieves intelligent control, and has high applicability. This invention is applicable to the power construction industry and is used for modal testing of large generator sets. Attached Figure Description

[0018] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0019] Figure 1 This is a schematic cross-sectional view of an embodiment of the present invention in the front view. Figure 2 For the embodiments of the present invention in Figure 1 Schematic diagram of the cross section in the AA direction; Figure 3 for Figure 1 Enlarged schematic diagram of part B; Figure 4 This is a schematic diagram of the application structure of an embodiment of the present invention; Figure 5 This is a schematic diagram of the structure of the automated control system in an embodiment of the present invention; Figure 6 This is a flowchart of the automated control method in an embodiment of the present invention.

[0020] In the diagram: 1-Support seat; 101-Mounting cavity; 2-Cylinder body; 21-Hollow chamber; 3-Piston; 31-Bearing plate; 32-Piston cylinder; 4-Vibration motor; 41-Motor part; 42-Stator part; 5-Air supply channel; 6-Air supply pipeline; 7-First support plate; 8-Second support plate; 9-Mounting ring; 10-Ball bearing; 11-Airbag ring; 12-Upper pressure ring; 13-Lower pressure plate; 14-Proportional control valve; 15-Displacement sensor; 16-Induction plate; 17-Generator set; 18-Pressure sensor; 19-Vertical mounting groove; 20-Support plate. Detailed Implementation

[0021] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the large generator set modal testing device and automated control system and method described herein are preferred embodiments and are only used for illustration and explanation of the present invention, and do not constitute a limitation thereof.

[0022] A first exemplary embodiment of the present invention provides a modal testing and detection device for a large generator set, such as... Figures 1-4 As shown, this embodiment includes a support 1, a cylinder 2, an air source, a piston 3, a vibration motor 4, and a load-bearing plate 31. The air source is mainly used to provide high-pressure gas, and its structure is existing technology and is not shown in the figure.

[0023] The support base 1 is made of high-strength aluminum alloy and serves as an integrated platform for air flotation and vibration excitation. The cylinder body 2 is fixed to the support base 1. Specifically, both the cylinder body 2 and the support base 1 are cylindrical structures. The support base 1 has a cylindrical mounting cavity 101 for placing the cylinder body 2. A mounting ring 9 extending away from the center of the cylinder body 2 is fixed to the outer periphery of the top of the cylinder body 2. In this embodiment, the cylinder body 2 and the mounting ring 9 are integrally formed, and the cylinder body 2 is supported on the top of the support base 1 via the mounting ring 9. After the cylinder body 2 is supported on the top of the support base 1, a gap is left between the bottom end of the cylinder body 2 and the inner bottom wall of the mounting cavity 101 to facilitate the installation of the air supply pipe 6.

[0024] like Figure 1As shown, the piston 3 includes a fixedly connected load-bearing plate 31 and piston cylinder 32. The load-bearing plate 31 is sealed and fixed to the top of the piston cylinder 32. In this embodiment, the load-bearing plate 31 and piston cylinder 32 are integrally formed. The piston cylinder 32 is sleeved on the outer wall of the cylinder body 2 and is airtightly connected to the cylinder body 2. The air source is connected to the hollow chamber 21 of the cylinder body 2 through the air supply pipe 6 and drives the piston 3 to move in the vertical direction. Specifically, in this embodiment, an air supply channel 5 is provided on the support seat 1. The air supply pipe 6 is set in the gap between the bottom end of the cylinder body 2 and the inner bottom wall of the mounting cavity 101. One end of the air supply pipe 6 is connected to the air supply channel 5, and the other end is connected to the inside of the cylinder body 2. The inside of the cylinder body 2 is a hollow chamber 21. The air source can supply high-pressure gas (0.3~0.8MPa) to the hollow chamber 21 through the air supply channel 5 and the air supply pipe 6 to drive the piston 3 to move in the vertical direction and achieve the air flotation bearing effect.

[0025] The specific method of airtight connection is as follows: Figure 1 , 3 As shown, an airbag ring 11 is provided between the piston 3 and the outer wall of the cylinder 2. The airbag ring 11 is made of rubber or polyurethane. Since traditional rubber sealing rings cannot dynamically adjust the pressure, an airbag ring 11 is used in this embodiment to control the support stiffness by the inflation volume. The structure of the airbag ring 11 is existing technology. The airbag ring 11 is sleeved on the outer circumference of the cylinder 2. The upper edge of the airbag ring 11 is fixedly connected to the piston cylinder 32 through the upper pressure ring 12, and the lower edge of the airbag ring 11 is fixedly connected to the cylinder 2 through the lower pressure plate 13. The longitudinal section of the upper pressure ring 12 is L-shaped. An annular groove is provided on the piston cylinder 32, and the upper pressure ring 12 is engaged in the annular groove. The upper end of the airbag ring 11 is fixedly connected to the upper pressure ring 12 in a sealed manner. The contact surface between the upper pressure ring 12 and the airbag ring 11 is coated with silicone grease lubricant to reduce friction and wear. The lower pressure plate 13 is an annular flat plate structure, which is fixed to the mounting ring 9 by screws. The lower end of the airbag ring 11 is sealed and fixedly connected to the lower pressure plate 13. The contact surface between the lower pressure plate 13 and the airbag ring 11 is provided with a buffer pad made of fluororubber with a thickness of 1mm to absorb vibration and impact. The buffer pad is not shown in the figure.

[0026] An airbag ring 11 is provided to form an annular sealed cavity, serving both support and sealing functions. When air is supplied to the hollow chamber 21 within the cylinder 2, the piston 3 is suspended, thus providing a lifting effect on the generator set 17 placed on the load-bearing plate 31. When the piston 3 is suspended, the airbag ring 11 can minimize the vertical stiffness, allowing the generator set 17 on the load-bearing plate 31 to exhibit an approximately unconstrained free state, thereby improving the accuracy of modal test results.

[0027] To satisfy the application of excitation force, such as Figure 1As shown, a vibration motor 4 is provided between the load-bearing plate 31 and the support 1. In this embodiment, the vibration motor 4 is an existing linear motor, but any other structure can be selected, such as a combination of a rotary motor and a crank-slider mechanism, which can also convert rotational motion into linear reciprocating motion to achieve vibration. The vibration motor 4 includes a stator 42 and a mover 41 arranged coaxially. The mover 41 is connected to the load-bearing plate 31 through a flange and outputs axial excitation force to drive the load-bearing plate 31 to perform vertical reciprocating vibration in the vertical direction. The stator 42 is fixedly mounted on the support 1 and coaxially sleeved on the outer periphery of the mover 41. Specifically, a first ring-shaped support plate 7 is fixedly provided on the support 1, and the stator 42 is fixedly mounted on the first support plate 7 through a second support plate 8. Figure 1 , 2 As shown, in this embodiment, multiple excitation motors 4 are provided, arranged at intervals along the circumference of the first support plate 7. Each excitation motor 4 is fixed to the first support plate 7 via a second support plate 8. The stator part 42 contains an electromagnetic coil, which generates an alternating magnetic field when energized. The mover part 41 moves vertically under the action of the magnetic field, transmitting the excitation force. In this embodiment, the excitation range of the excitation motor 4 is 0.1 to 10 kN, and the frequency response is 0.1 to 200 Hz, covering the main vibration modes of the generator set.

[0028] Furthermore, in order to reduce frictional resistance, such as Figure 1 As shown, at least one row of vertical mounting slots 19 is provided on the outer wall of the cylinder body 2. In this embodiment, there are two rows of vertical mounting slots 19, which are arranged at intervals along the axial direction (i.e., vertical direction) of the cylinder body 2. Each row of vertical mounting slots 19 includes multiple vertical mounting slots 19 spaced apart along the circumferential direction of the outer wall of the cylinder body 2, such as... Figure 2 As shown, in this embodiment, each row of vertical mounting slots 19 includes eight vertical mounting slots 19. For example... Figure 1 As shown, each vertical mounting slot 19 is uniformly fitted with multiple rolling elements, which are ball bearings 10, similar to the structure of a bearing. In this embodiment, each vertical mounting slot 19 contains four ball bearings 10, that is, each row of vertical mounting slots 19 contains a total of 32 ball bearings 10, and the two rows of vertical mounting slots 19 contain a total of 64 ball bearings 10. The number of vertical mounting slots 19 and the number of ball bearings 10 can be adjusted according to actual applications. The multiple ball bearings 10 are rotatably fixed in the vertical mounting slots 19 by ball bearing retainers. Since the structure and fixing method of the ball bearing retainers and the connection relationship between the ball bearings 10 and the ball bearing retainers are existing technologies, they will not be described in detail in this embodiment. The ball bearings 10 are exposed in the vertical mounting slots 19 and roll in contact with the inner wall of the piston cylinder 32. When the load-bearing plate 31 moves in air-float motion driven by high-pressure gas or vibrates at high frequency under the action of the excitation motor 4, the ball bearing 10 rolls back and forth rapidly, converting the sliding friction between the piston 3 and the cylinder 2 into rolling friction, and reducing the frictional resistance to below 5N.

[0029] When using this embodiment, as follows: Figure 1 , 4 As shown, air is supplied to the hollow chamber 21 of the cylinder 2 via air supply channel 5 and air supply pipeline 6. The piston 3 is suspended, lifting the generator set 17 placed on the support plate 31 to the required support height. Then, the excitation motor 4 applies excitation force to the generator set 17 for modal testing. This device integrates air-bearing support and excitation functions into one device, reducing the device volume by 40%, simplifying the device structure, achieving the dual effects of support and excitation force application, and reducing installation and commissioning time from 4 hours to 30 minutes. It reduces pre-test preparation work and in-test procedures, making it more convenient and improving testing accuracy and efficiency. For supporting and testing large generator sets 17, simply increase the number of support plates 31 in this embodiment to support a large generator set 17. See [link to relevant documentation]. Figure 4 .

[0030] This embodiment boasts advantages such as high load-bearing capacity, low stiffness, and high excitation frequency. It combines air-bearing technology with electromagnetic excitation technology, enabling the device itself to bear loads and eliminating the need for additional support devices. The air-bearing technology places the generator set 17 in a near-free and unconstrained state, saving significant material and labor costs. The excitation motor 4 provides the excitation force, increasing the force transmission efficiency to 98% (compared to ≤85% for traditional equipment). This improves the accuracy of modal test results, effectively shortens the test cycle, increases test efficiency, and ensures the accuracy of the generator set modal tests, enabling the determination of whether the generator set 17 can be used normally in the future.

[0031] A second exemplary embodiment of the present invention provides an automated control system for automating the first exemplary embodiment, such as... Figure 1 , 5 As shown, this embodiment includes a controller and a proportional control valve 14. The controller, proportional control valve 14, and their connection relationship are all prior art. The controller is not shown in the figure. The controller is installed on the outer wall of the support 1 or in a separate control box, close to the proportional control valve 14, to reduce signal transmission distance. In this embodiment, the proportional control valve 14 is fixed to the first support plate 7 of the support 1. The outlet end of the proportional control valve 14 is connected to the gas supply line 6 to regulate the gas flow rate and pressure of the gas supply line 6. In this embodiment, the control accuracy is ±0.05MPa. Figure 1As shown, the first support plate 7 is also equipped with an air supply channel 5, which is connected to the air supply channel 5 on the support seat 1. The outlet end of the proportional control valve 14 is also connected to the air supply channel 5 of the first support plate 7 through an air supply pipe 6. The proportional control valve 14 is electrically connected to the controller to receive control commands and realize automatic adjustment of the intake pressure. Working principle: The piston 3 floats at a height set according to the support height requirement. The controller sends a control command to the proportional control valve 14, so that high-pressure gas is sent to the cylinder 2 through the air supply channel 5 and the air supply pipe 6, thereby pushing the piston 3 to move upward to the set height.

[0032] To monitor the suspension height of the load-bearing plate 31, this embodiment also includes a displacement sensor 15 and a sensing plate 16, both of which are existing technologies. Figure 1 As shown, the sensing plate 16 is fixed on the side of the load-bearing plate 31 facing the support base 1 (i.e., the bottom surface of the load-bearing plate 31), and the displacement sensor 15 is fixed on the support base 1 at the position corresponding to the sensing plate 16. In this embodiment, an L-shaped support plate 20 is fixed on the first support plate 7, and the displacement sensor 15 is fixed on the support plate 20. The displacement sensor 15 is electrically connected to the controller, and the displacement sensor 15 monitors the displacement of the piston 3 (i.e., the suspension height) in real time and feeds it back to the controller. The working principle is as follows: Figure 5 As shown, the displacement sensor 15 monitors the displacement of the load-bearing plate 31 in real time and sends the displacement signal to the controller, which then determines the support height of the piston 3. If the displacement is caused by the change in the weight of the generator set 17, the displacement sensor 15 will feed back to the controller. The controller will adjust the proportional control valve 14 to increase or decrease the air supply, thereby adjusting the support height of the generator set 17, maintaining the constant suspension height of the load-bearing plate 31, achieving a precise load-bearing effect, and improving the accuracy of the test.

[0033] like Figure 1 As shown, this embodiment also includes a pressure sensor 18 disposed between the excitation motor 4 and the support 1. The pressure sensor 18 adopts existing technology. In this embodiment, the pressure sensor 18 is disposed between the first support plate 7 and the second support plate 8. The pressure sensor 18 is electrically connected to the controller to transmit pressure parameters. The controller is electrically connected to the excitation motor 4. The controller can send excitation commands to the excitation motor 4. The excitation motor 4 applies sinusoidal excitation with a specified peak force to the generator set 17 through the piston 3 in the form of a fixed frequency or a swept frequency. The working principle is as follows: Figure 5 As shown, the pressure sensor 18 feeds back the air flotation pressure parameter to the controller. The controller determines whether the frequency and amplitude of the AC power of the exciter motor 4 need to be adjusted according to the preset program and sends an excitation command to the exciter motor 4, thereby controlling the exciter motor 4 to apply the target excitation force to the generator set 17 to ensure the accuracy of the applied excitation force.

[0034] In summary, the controller in this embodiment has two functions: first, adjusting the air-float height of piston 3: based on feedback from displacement sensor 15, dynamically adjusting the opening of proportional control valve 14 to maintain the set suspension height; second, controlling the excitation force: by adjusting the current of excitation motor 4, controlling the magnitude and frequency of the output force of actuator 41.

[0035] A third exemplary embodiment of the present invention provides an automated control method, which employs a second exemplary embodiment, such as... Figure 6 As shown, the specific steps include: S1. Air Float Pressure Setting; Calculate the required air float pressure based on the weight of generator set 17, and set the initial value through the controller; In this embodiment, the weight of generator set 17 is 50 tons, and the required air float pressure is 0.5MPa.

[0036] S2. Input excitation force parameters; input the target excitation force and frequency, and the controller will automatically match the excitation motor current; in this embodiment, the target excitation force is 5KN, the frequency is 50Hz, and the excitation motor current is 20A.

[0037] S3. Turn on the air source and controller, and piston 3 will float to the set height of 50mm.

[0038] S4. Vibration test; The controller sends a command, and the vibration motor 4 applies the target vibration force at the input frequency for a certain period of time; In this embodiment, the vibration motor 4 applies a 5KN vibration force at a frequency of 50Hz for 10 seconds.

[0039] S5. Data Acquisition; Record the vibration signal of generator set 17 through the accelerometer and analyze modal parameters such as natural frequency and damping ratio; S6. Automatic adjustment: If the air flotation pressure fluctuation exceeds the limit during the test (e.g., exceeding ±0.1MPa), the controller dynamically adjusts the opening of the proportional control valve 14 to maintain stable air flotation pressure.

[0040] This step also includes an intelligent adjustment phase, which includes the following: Dynamic balance; displacement sensor 15 monitors the height of piston 3 in real time. If a deviation is detected, the controller adjusts the proportional control valve 14 to increase or decrease the air supply to maintain a constant suspension height. Vibration force closed-loop control: Pressure sensor 18 monitors air flotation pressure fluctuations, and the controller synchronously adjusts the output force of the excitation motor 4 to ensure that the vibration force amplitude is stable (i.e., fluctuation ≤ ±2%).

[0041] S7. Output the test results.

[0042] The modal frequency detection error obtained using the above embodiments is ≤0.1Hz (≥0.5Hz using traditional methods); and under a wide frequency excitation of 5Hz to 200Hz, the air float height fluctuation is ≤±0.05mm, thus exhibiting strong anti-interference capability.

[0043] It should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions described in the above embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A modal testing and detection device for large generator sets, characterized in that, The device includes a support base, a cylinder, an air source, a piston, a vibration motor, and a load-bearing plate. The cylinder is fixed on the support base and has a hollow chamber inside. The piston includes a load-bearing plate and a piston cylinder that are fixedly connected. The piston cylinder is sleeved on the outer wall of the cylinder and is airtightly connected to the cylinder. The air source is connected to the hollow chamber of the cylinder through an air supply pipeline and drives the piston to move vertically. The load-bearing plate is sealed and fixed to the top of the piston cylinder. The vibration motor is located between the load-bearing plate and the support base. The vibration motor includes a stator and a mover that are coaxially arranged. The mover is fixedly connected to the load-bearing plate and outputs axial excitation force to drive the load-bearing plate to reciprocate vertically. The stator is fixed on the support base and coaxially sleeved on the outer periphery of the mover. An air bladder ring is provided between the piston and the outer wall of the cylinder body. The air bladder ring is sleeved around the outer periphery of the cylinder body. The upper edge of the air bladder ring is fixedly connected to the piston through an upper pressure ring, and the lower edge of the air bladder ring is fixedly connected to the cylinder body through a lower pressure plate. At least one row of vertical mounting slots is provided on the outer wall of the cylinder body. Each row of vertical mounting slots includes multiple vertical mounting slots arranged at intervals along the circumference of the outer wall of the cylinder body. Multiple rolling elements are uniformly embedded in each vertical mounting slot. The rolling elements are exposed outside the vertical mounting slot and roll in contact with the inner wall of the piston. The upper pressure ring has an L-shaped longitudinal section, and an annular groove is provided on the piston cylinder, into which the upper pressure ring engages. The upper end of the airbag ring is fixedly connected to the upper pressure ring in a sealed manner. The contact surface between the upper pressure ring and the airbag ring is coated with silicone grease lubricant to reduce friction and wear. The lower pressure plate is an annular flat plate structure, which is fixed to the mounting ring with screws. The lower end of the airbag ring is fixedly connected to the lower pressure plate in a sealed manner. The contact surface between the lower pressure plate and the airbag ring is provided with a 1mm thick buffer pad made of fluororubber to absorb vibration and impact. A first ring-shaped support plate is fixed on the support base, and the stator is fixed on the first support plate through a second support plate; multiple exciter motors are provided and arranged at intervals along the circumference of the first support plate, and each exciter motor is fixed on the first support plate through a second support plate; the stator contains an electromagnetic coil, which generates an alternating magnetic field when energized, and the mover moves vertically under the action of the magnetic field, transmitting the excitation force.

2. The large generator set modal testing and detection device according to claim 1, characterized in that, The excitation motor is a linear motor.

3. The large generator set modal testing and detection device according to claim 1 or 2, characterized in that, The support is made of high-strength aluminum alloy.

4. An automated control system for automatically controlling the large generator set modal testing device according to any one of claims 1-3, characterized in that, It includes a controller and a proportional control valve; the proportional control valve is fixed on the support and electrically connected to the controller, and the outlet end of the proportional control valve is connected to the air supply pipeline.

5. The automated control system according to claim 4, characterized in that, It also includes a displacement sensor and a sensing plate. The sensing plate is fixed on the side of the load-bearing plate facing the support. The displacement sensor is fixed on the support at the position corresponding to the sensing plate. The displacement sensor is electrically connected to the controller. The displacement sensor monitors the piston displacement in real time and feeds it back to the controller.

6. The automated control system according to claim 5, characterized in that, It also includes a pressure sensor located between the exciter motor and the support, the pressure sensor being electrically connected to the controller to transmit pressure parameters, and the controller being electrically connected to the exciter motor.

7. An automated control method, employing the automated control system according to any one of claims 4-6, characterized in that, The method includes the following steps: S1. Air Float Pressure Setting; Calculate the required air float pressure based on the generator set weight and set the initial value via the controller; S2. Input excitation force parameters; input the target excitation force and frequency, and the controller will automatically match the excitation motor current; S3. Turn on the air supply and controller, and the piston will float to the set height; S4. Vibration test: The controller sends a command, and the excitation motor applies the target excitation force at the input frequency for a certain period of time. S5. Data Acquisition; Record the vibration signals of the generator set using an accelerometer and analyze its modal parameters; S6. Automatic adjustment; if the air flotation pressure fluctuation exceeds the limit during the test, the controller dynamically adjusts the opening of the proportional control valve to maintain stable air flotation pressure; S7. Output the test results.

8. The automated control method according to claim 7, characterized in that, Step S6 also includes an intelligent adjustment stage, which includes the following: Dynamic balance; the displacement sensor monitors the piston height in real time. If a deviation is detected, the controller adjusts the proportional control valve to increase or decrease the air supply to maintain a constant suspension height. Closed-loop control of excitation force: a pressure sensor monitors air flotation pressure fluctuations, and the controller synchronously adjusts the output force of the excitation motor to ensure stable excitation force amplitude.

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