Hydroelectric main shaft all-condition simulation test system and method

Abstract

The invention relates to a hydroelectric main shaft all-condition simulation test system and method, and the system comprises a fixed rack, one side of the fixed rack is provided with a tripping starting detection device, the fixed rack is provided with a hollow three-axis platform, a three-axis excitation system and a rotation driving part, the moving end of the three-axis platform is connected with a hollow floating rack, and a bearing is disposed in the floating rack. The rotation driving part comprises a power part and a main shaft connected to the torque output end of the power part, the main shaft is in transmission connection with the rotating disc, a hydroelectric large shaft used for a simulation test is installed on the rotating disc, and the three-shaft excitation system is used for applying X-direction, Y-direction and Z-direction high-frequency sine excitation loads to the hydroelectric large shaft of the rotating disc. The device is used for overcoming the defects that an existing testing device mainly focuses on vibration loading of a static mechanical device, simulation and performance testing cannot be carried out on dynamic behaviors under the composite working conditions of rotation, vibration and impact of a hydroelectric large shaft, and safety testing and rating cannot be carried out on a hydroelectric generating set sensor and a tripper overspeed protection device.

Description

Technical Field

[0001] This invention relates to a full-condition simulation test system and method for hydroelectric main shafts. Background Technology

[0002] Hydropower turbine generator sets are the core equipment of hydropower stations, and the main shaft is a key component connecting the turbine and the generator. It endures complex coupled loads such as torsion, bending, rotation, all-directional vibration, and instantaneous impact, which often degrades its working condition, accelerates fatigue failure, and leads to major production accidents and huge economic losses. Accurate simulation of the dynamic behavior of the main shaft and regular testing and evaluation of the safety performance of vibration sensors, sway sensors, and overspeed protection devices of the trip unit are crucial for maintenance and management personnel to fully understand its operating patterns, improve the reliability of actual operation and condition monitoring, facilitate rapid early fault diagnosis and pre-treatment of hydropower units, and are of great significance in preventing further escalation of accidents. However, due to the complex operating conditions, large structural dimensions, and large rotational inertia and load of hydropower main shafts, simulating their actual operating conditions is very difficult. Most of the patents currently found focus on vibration loading tests of static mechanical devices. They cannot solve the problems of combined rotation, triaxial excitation, and hammer impact loading of large heavy-duty mechanical equipment such as hydropower main shafts. They cannot simulate and test the dynamic behavior of hydropower main shafts under combined rotation, vibration, and impact conditions, nor can they conduct safety tests and ratings for overspeed protection devices of hydropower unit sensors and trip units. Summary of the Invention

[0003] The purpose of this invention is to provide a full-condition simulation test system and method for hydropower main shafts, in order to solve the shortcomings of existing test devices, which are mainly focused on vibration loading of static mechanical devices, and cannot simulate and test the dynamic behavior of hydropower main shafts under combined conditions of rotation, vibration and impact, and cannot conduct safety testing and rating of overspeed protection devices for hydropower unit sensors and trip units.

[0004] To solve the above problems, the technical solution of the present invention is as follows: A full-condition simulation test system for a hydroelectric main shaft includes a fixed platform with a trip start detection device on one side. A hollow triaxial platform, a triaxial vibration system, and a rotary drive unit are mounted on the fixed platform. A hollow floating platform is connected to the moving end of the triaxial platform, and bearings are installed inside the floating platform. The rotary drive unit includes a power unit and a main shaft connected to the torque output end of the power unit. The main shaft passes through the triaxial platform and the bearings in sequence and is then connected to a turntable for transmission. The hydroelectric main shaft used for simulation testing is mounted on the turntable. The triaxial vibration system is used to apply high-frequency sinusoidal excitation loads in the X, Y, and Z directions to the hydroelectric main shaft on the turntable.

[0005] Furthermore, the main hydroelectric shaft includes a simulated base rod, with adjustable extension rods installed at both ends of the simulated base rod. A tripping centrifugal block is connected to the left adjustable extension rod, and a balancing mass block is connected to the right adjustable extension rod. The simulated base rod is mounted on the turntable by a clamp.

[0006] Furthermore, the trip unit activation detection device includes a ground rail, a trolley mounted on the ground rail, a column fixedly connected to the trolley, a first linear module and a second linear module mounted on the top of the column, a trip unit trigger probe mounted on the moving end of the first linear module, a camera bracket connected to the moving end of the second linear module, and a high-speed camera mounted on the camera bracket.

[0007] Furthermore, the power unit includes a main motor, the output shaft of which is connected to the input shaft of the reducer via a coupling, and the output shaft of the reducer is connected to the lower end of the main shaft via a flexible coupling.

[0008] Furthermore, the hollow floating platform has a double-layer platform structure. The hollow floating platform is supported on the platform of the fixed platform by multiple elastic foot pads. Each elastic foot pad is equipped with a limiting and fixing device. The limiting and fixing device includes a shaft tube opened on the hollow floating platform, a support shaft inserted into the shaft tube, a slot opened at the upper end of the support shaft, a trapezoidal expansion block in the slot, the expansion block is connected to the slot by a screw, and a squeezing block is provided on both sides of the expansion block. The squeezing block cooperates with the inclined surface of the trapezoidal inclined block.

[0009] Furthermore, the three-axis platform includes a hollow guide frame, with multiple Z-axis sliders connected around the guide frame. Z-axis guide rails assembled inside the Z-axis sliders are connected to a fixed platform. Multiple X-axis guide rails are installed on the guide frame, with multiple X-axis sliders assembled on the X-axis guide rails. Y-axis sliders are connected to the X-axis sliders, with multiple Y-axis guide rails assembled inside the multiple Y-axis sliders. The floating platform is connected to the multiple Y-axis guide rails. Furthermore, the triaxial excitation system includes an X-axis excitation device, a Y-axis excitation device, a Z-axis excitation device, an X-axis sway sensor, and a Y-axis sway sensor. The X-axis and Y-axis excitation devices are mounted on a fixed frame at a 90-degree angle. The X-axis sway sensor is connected to the X-axis excitation device via a right-angle bracket, and the Y-axis sway sensor is connected to the Y-axis excitation device via a right-angle bracket. The triaxial platform is set on the Z-axis excitation device.

[0010] Furthermore, the X-axis excitation device and the Y-axis excitation device have the same structure. The X-axis excitation device includes a support fixedly connected to a fixed platform, a first servo reduction motor mounted on the support, the output shaft of the first servo reduction motor connected to a cam oscillator, a vibration seat surrounding the cam oscillator, and the vibration seat connected to one side of the floating platform.

[0011] Furthermore, the Z-axis excitation device includes a hollow hydraulic cylinder and a support plate connected to a fixed frame. A second servo reduction motor and a pilot cylinder are mounted on the support plate. The two chambers of the pilot cylinder are connected to the two chambers of the hollow hydraulic cylinder through hydraulic oil pipes. The output shaft of the second servo reduction motor is connected to the piston rod of the pilot cylinder through a cam reciprocating mechanism.

[0012] Furthermore, it also includes an impact force application system, which includes a hammering device, a horizontal vibration sensor, a vertical vibration sensor, and multiple brake calipers. The hammering device is mounted on a fixed platform and is used to apply a horizontal hammering instantaneous impact load to the water and electricity shaft of the turntable. The horizontal vibration sensor and the vertical vibration sensor are respectively mounted on the side and lower surface of the floating platform. Each brake caliper is mounted on the floating platform, and a skirt is provided around the edge of the turntable, with the skirt located inside the brake caliper. Furthermore, the hammering device includes a support frame mounted on a fixed platform, on which a third servo motor and a driven shaft are mounted. The output shaft of the third servo motor is connected to the driven shaft via a synchronous belt transmission mechanism. A magnetic powder brake is mounted on the driven shaft and is connected to the hammer. A test method for simulating the full operating conditions of a hydroelectric main shaft includes the following steps: S1. Based on the required simulated hydraulic shaft diameter, select a suitable hydraulic shaft and fix it on the turntable. Adjust the trip unit to start the detection device to the detection position. S2. The rotary drive unit drives the main shaft of the hydroelectric power plant to rotate at a preset speed, simulating different speed operating conditions; S3. Start the triaxial excitation system to apply high-frequency sinusoidal excitation loads in the X, Y, and Z directions to the main shaft of the hydroelectric power plant; S4. Activate the hammering device to strike the side of the floating platform with a heavy hammer to apply a horizontal hammering instantaneous impact load to the hydroelectric main shaft; S5. During steps S3 and S4, the dynamic behavior of the hydroelectric main shaft is detected by horizontal vibration sensor, vertical vibration sensor, X-axis swing sensor and Y-axis swing sensor; the triggering process of the trip unit centrifugal block is recorded by high-speed camera to evaluate the performance of the trip unit overspeed protection device.

[0013] Furthermore, the feature is that, during steps S3 to S5, if a dangerous situation occurs during the test, the brake caliper is activated to clamp the skirt of the turntable, thereby achieving emergency braking of the hydroelectric shaft simulation device. Furthermore, if the main shaft of the hydroelectric system needs to rotate under conditions where it is not subjected to combined loads of X, Y, and Z-axis vibration and hammering, a limiting and fixing device shall be used to fix the floating platform and the fixed platform.

[0014] The beneficial effects of this invention are as follows: By integrating rotation, vibration, and impact composite loading methods, it solves the shortcomings of existing testing devices that can only apply vibration loading to static mechanical devices. It realizes the simulation and performance testing of dynamic behavior under combined working conditions of rotation, vibration, and impact on the main shaft of hydropower units. Furthermore, it can complete the accuracy, safety, and reliability testing and rating of overspeed protection devices for hydropower unit sensors and trip units. The dynamic working condition simulation is more realistic, providing scientific testing equipment for mastering the dynamic operation law of hydropower units, fault diagnosis and handling, and safe operation and maintenance. Attached Figure Description

[0015] The invention will be further described below with reference to the accompanying drawings: Figure 1 This is a three-dimensional structural diagram of the present invention. Figure 2 This is a three-dimensional structural diagram of the present invention. Figure 3 This is a partial three-dimensional structural diagram of the present invention. Figure 4 This is a partial three-dimensional structural diagram of the present invention. Figure 5 This is a partial three-dimensional structural diagram of the present invention. Figure 6 This is a partial three-dimensional structural diagram of the present invention. Figure 7 This is a partial three-dimensional structural diagram of the present invention. Figure 8 This is a three-dimensional structural diagram of the three-axis platform of the present invention. Figure 9 This is a three-dimensional structural diagram of the Z-axis excitation device of the present invention. Figure 10 This is a front view schematic diagram of the trip start detection device of the present invention. Figure 11 This is a cross-sectional structural diagram of the limiting and fixing device of the present invention. Figure 12 This is a three-dimensional structural diagram of the limiting and fixing device of the present invention. Figure 13 This is a three-dimensional structural diagram of the hammering device of the present invention. Figure 14 This is a hydraulic schematic diagram of the present invention.

[0016] In the diagram: Rotary drive unit 100, main motor 101, reducer 102, flexible coupling 103, bearing 104, main shaft 105, trip start detection device 200, high-speed camera 201, trip trigger probe 202, first linear module 203, column 204, trolley 205, second linear module 206, camera bracket 207, ground rail 208, three-axis platform 300, Z-axis slider 301, Z-axis guide rail 302, hollow guide frame 303, X-axis guide rail 304, X-axis slider 305, Y-axis slider 306, Y-axis guide rail 307, hydroelectric main shaft 400, adjustable extension rod 401, simulated base rod 402, balance mass block 404, clamp 403, trip centrifugal block 405, hollow floating platform 500, turntable 600, skirt 601, elastic foot pad 700, X The following components are included: excitation device 810, support 811, first servo geared motor 812, cam oscillator 813, vibration seat 814, Z-axis excitation device 820, cam reciprocating mechanism 821, hollow oil cylinder 822, second servo geared motor 823, pilot cylinder 824, hammering device 830, counterweight 831, support frame 832, magnetic powder brake 833, synchronous belt drive mechanism 834, third servo motor 835, driven shaft 836, brake caliper 840, Y-axis excitation device 850, X-axis swing sensor 861, Y-axis swing sensor 862, horizontal vibration sensor 871, vertical vibration sensor 872, limit fixing device 900, support shaft 901, extrusion block 902, trapezoidal expansion block 903, flange 904, shaft tube 905, and fixed platform 110. Detailed Implementation

[0017] 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.

[0018] like Figure 1 and 2As shown, a full-condition simulation test system for a hydroelectric main shaft includes a fixed platform 110. A tripping start detection device 200 is provided on one side of the fixed platform 110. A hollow triaxial platform 300, a triaxial excitation system, and a rotary drive unit 100 are provided on the fixed platform 110. A hollow floating platform 500 is connected to the moving end of the triaxial platform 300. The hollow floating platform 500 can move along the X, Y, and Z directions. A bearing 104 is installed inside the floating platform 500. The rotary drive unit 100 includes a power unit and a hollow main shaft 105 connected to the torque output end of the power unit. The main shaft 105 passes through the triaxial platform 300 and the bearing 104 from bottom to top and is connected to the turntable 600 for transmission. The hydroelectric main shaft 400 used for simulation test is fixedly installed on the turntable 600 by multiple clamps 403. The triaxial excitation system is used to apply high-frequency sinusoidal excitation loads in the X, Y, and Z directions to the hydroelectric main shaft 400 installed on the turntable 600.

[0019] like Figure 1 As shown, the hydroelectric shaft 400 further includes a simulated base rod 402, with adjustable extension rods 401 installed at both ends. A trip unit centrifugal block 405 is connected to the left adjustable extension rod 401, and a balance mass block 404 is connected to the right adjustable extension rod 401. The simulated base rod 402 is mounted on the turntable 600 via a clamp 403. The simulated base rod 402 has different length specifications. By replacing the simulated base rod 402 with different specifications, hydroelectric shafts 400 of different length ranges can be simulated. Adjusting the left and right adjustable extension rods 401 can further configure more length specifications based on the length of the simulated base rod 402, so that the hydroelectric shaft simulation device of the test system of the present invention can simulate the rotational operation of hydroelectric shafts 400 with more diameter specifications.

[0020] like Figure 1 and 10 As shown, the trip unit activation detection device 200 further includes a ground rail 208, a trolley 205 mounted on the ground rail 208, a column 204 fixedly connected to the trolley 205, a first linear module 203 and a second linear module 206 mounted on the top of the column 204, a trip unit trigger probe 202 mounted on the moving end of the first linear module 203, a camera bracket 207 connected to the moving end of the second linear module 206, and a high-speed camera 201 mounted on the camera bracket 207. The distance between the trip unit trigger probe 202 and the trip unit centrifugal block 405 can be finely adjusted using the first linear module 203 to meet installation requirements; the position of the high-speed camera 201 can be finely adjusted using the second linear module 206 so that the field of view of the high-speed camera 201 is directly facing the trip unit trigger probe 202, so that the triggering process can be fully recorded, thereby determining the accuracy, safety and reliability of the trip unit measurement; dragging the trolley 205 on the ground rail 208 can coarsely adjust the distance between the trip unit trigger probe 202 and the trip unit centrifugal block 405.

[0021] like Figure 6 and 7 As shown, the power unit further includes a main motor 101. The output shaft of the main motor 101 is connected to the input shaft of the reducer 102 via a rigid coupling. The output shaft of the reducer 102 is connected to the lower end of the main shaft 105 via a flexible coupling 103. The main motor 101 is a variable frequency motor. By adjusting the frequency converter connected to the main motor 101, the speed of the main motor 101 can be adjusted. Adjusting the speed of the main motor 101 can control the hydroelectric main shaft simulation device to operate at different speeds. The flexible coupling 103 gives the transmission shaft system a degree of freedom of multi-directional (axial, radial, angular) micro-amplitude movement to accommodate the displacement generated by high-frequency sinusoidal excitation loads in the X, Y, and Z directions and instantaneous impact loads from horizontal hammering.

[0022] like Figure 1 , 2 As shown in Figure 5, furthermore, the hollow floating platform 500 has a double-layer platform structure. The hollow floating platform 500 is supported on the platform of the fixed platform 110 by four elastic foot pads 700. Each elastic foot pad 700 is equipped with a limiting and fixing device 900. Figure 11 and 12 As shown, the limiting and fixing device 900 includes a shaft tube 905 formed on the hollow floating platform 500. A support shaft 901 is inserted into the shaft tube 905. A flange 904 is provided at the lower end of the support shaft 901. A slot is formed at the upper end of the support shaft 901. A trapezoidal expansion block 903 is provided in the slot. The expansion block 903 is connected to the slot by a screw. An extrusion block 902 is provided on both sides of the expansion block 903. The extrusion block 902 cooperates with the inclined surface of the trapezoidal inclined block. Four elastic foot pads 700 give the floating platform 500 a degree of freedom of micro-movement in multiple directions (axial, radial, and angular) to adapt to the displacement generated by high-frequency sinusoidal excitation loads in the X, Y, and Z directions and instantaneous impact loads from horizontal hammering. It can simulate the dynamic vibration and impact load conditions of the hydroelectric main shaft 400. If the main shaft 400 of the hydroelectric system needs to rotate under conditions where it is not subjected to combined loads of X, Y, and Z-axis vibration and hammering, connect the lower flange of the support shaft 901 to the fixed frame 110, then use a wrench to tighten the screw, and use the inclined surfaces on both sides of the expansion block 903 to push the pressing block 902 outward to tighten the shaft tube 905, so as to fix the floating frame 500.

[0023] like Figure 8As shown, the three-axis platform 300 further includes a hollow guide frame 303, with four Z-axis sliders 301 connected around the guide frame 303. Z-axis guide rails 302, assembled within the Z-axis sliders 301, are connected to the fixed platform 110. Two X-axis guide rails 304 are mounted on the guide frame 303, and two X-axis sliders 305 are mounted on the X-axis guide rails 304. Y-axis sliders 306 are connected to the X-axis sliders 305, and two Y-axis guide rails 307 are assembled within the two Y-axis sliders 306. The floating platform 500 is connected to multiple Y-axis guide rails 307. This structure allows the hydroelectric shaft 400 mounted on the turntable 600 to adapt to the displacement caused by X, Y, and Z-axis impact loads, and the structure is simple and reliable.

[0024] like Figure 4 and 5 As shown, the triaxial vibration system further includes an X-axis excitation device 810, a Y-axis excitation device 850, a Z-axis excitation device 820, an X-axis sway sensor 861, and a Y-axis sway sensor 862. The X-axis excitation device 810 and the Y-axis excitation device 850 are mounted at a 90-degree angle on the fixed platform 110. The X-axis sway sensor 861 is connected to the X-axis excitation device 810 via a right-angle bracket, and the Y-axis sway sensor 862 is connected to the Y-axis excitation device 850 via a right-angle bracket. The triaxial platform 300 is set on the Z-axis excitation device 820. The X and Y axis excitation forces can be applied to the hydroelectric main shaft 400 through the floating platform 500.

[0025] Furthermore, the X-axis excitation device 810 and the Y-axis excitation device 850 have the same structure. The X-axis excitation device 810 includes a support 811 fixedly connected to the fixed platform 110. A first servo reduction motor 812 is installed on the support 811. The output shaft of the first servo reduction motor 812 is connected to a cam oscillator 813. The cam oscillator 813 is fitted with a vibration seat 814. The vibration seat 814 is connected to one side of the floating platform 500.

[0026] like Figure 6 and 7As shown, the Z-axis vibration device 820 further includes a hollow hydraulic cylinder 822 and a support plate connected to a fixed frame 110. A second servo reduction motor 823 and a pilot cylinder 824 are mounted on the support plate. The two chambers of the pilot cylinder 824 are connected to the two chambers of the hollow hydraulic cylinder via hydraulic oil pipes. The output shaft of the second servo reduction motor 823 is connected to the piston rod of the pilot cylinder 824 via a cam reciprocating mechanism 821. After the second servo reduction motor 823 starts, it drives the piston rod of the pilot cylinder 824 to reciprocate via the cam reciprocating mechanism 821. Since the two chambers of the pilot cylinder 824 are connected to the two chambers of the hollow hydraulic cylinder, the small flow and small displacement of the pilot cylinder 824 are converted into a large flow and large displacement of the hollow hydraulic cylinder using the hydraulic amplification principle. This drives the piston of the hollow hydraulic cylinder to reciprocate rapidly, thereby driving the hydroelectric shaft 400 to achieve high-frequency Z-axis vibration.

[0027] like Figure 3 and 13 As shown, the device further includes an impact force application system, which comprises a hammering device 830, a horizontal vibration sensor 871, a vertical vibration sensor 872, and multiple brake calipers 840. The hammering device 830 is mounted on the fixed platform 110 and is used to apply a horizontal hammering instantaneous impact load to the hydroelectric shaft of the turntable 600. The horizontal vibration sensor 871 and the vertical vibration sensor 872 are respectively mounted on the side and lower surface of the floating platform 500. Each brake caliper 840 is mounted on the floating platform 500. A skirt 601 is provided around the edge of the turntable 600, and the skirt 601 is located inside the brake calipers 840. If a dangerous situation occurs during the test, the brake calipers 840 are activated to clamp the skirt 601, thereby achieving emergency braking of the hydroelectric shaft simulation device. The X-axis sway sensor 861, Y-axis sway sensor 862, horizontal vibration sensor 871, and vertical vibration sensor 872 can detect the dynamic behavior of the hydroelectric shaft 400 under the action of rotation, excitation, and instantaneous impact coupled loads, and can also verify the accuracy, safety, and reliability of the related sensor measurements.

[0028] like Figure 13As shown, the hammering device 830 further includes a support frame 832 mounted on a fixed platform 110. A third servo motor 835 and a driven shaft 836 are mounted on the support frame 832. The output shaft of the third servo motor 835 is connected to the driven shaft 836 via a synchronous belt transmission mechanism 834. A magnetic powder brake 833 is mounted on the driven shaft 836 and is connected to the hammer 831. During operation, the magnetic powder brake 833 is energized, locking the hammer 831 and the driven shaft 836 together. Driven by the third servo motor 835, the driven shaft 836 rotates at a certain angle. After the hammer 831 is raised to a suitable height, the magnetic powder brake 833 is de-energized, and the hammer 831 is unlocked from the driven shaft 836. Under inertia, it strikes the side of the floating platform 500, applying an instantaneous hammering force to the hydraulic shaft 400.

[0029] A test method for simulating the full operating conditions of a hydroelectric main shaft 400 includes the following steps: S1. Select a suitable simulation base rod 402 according to the required diameter specification of the simulated hydroelectric shaft 400, and fix the simulation base rod 402 on the turntable 600 by clamping. Adjust the left adjustable extension rod 401 and the right adjustable extension rod 401 to the required length, and connect the trip unit centrifugal block 405 and the balance mass block 404 respectively. Adjust the position of the trip unit start detection device 200 so that the trip unit trigger probe 202 and the high-speed camera 201 are in the appropriate detection position.

[0030] S2. Start the main motor 101. The main motor 101 drives the turntable 600 to rotate through the rigid coupling, reducer 102, flexible coupling 103 and main shaft 105 to simulate the rotation of the hydropower main shaft 400. Different speed conditions can be simulated by adjusting the speed of the main motor 101 through the frequency converter. S3. Start the X-axis excitation device 810, Y-axis excitation device 850 and Z-axis excitation device 820 respectively. The X-axis excitation device and the Y-axis excitation device drive the cam oscillator 813 and the vibration seat 814 through the first servo reduction motor 812 to apply X and Y-axis high-frequency sinusoidal excitation loads to the floating platform 500; the Z-axis excitation device 820 applies Z-axis high-frequency sinusoidal excitation loads to the hydroelectric shaft 400 on the turntable 600. S4. Start the hammering device 830. First, the magnetic powder brake 833 is energized, locking the hammer 831 and the driven shaft 836. Driven by the third servo motor 835, the driven shaft 836 rotates at a certain angle. After the hammer 831 is raised to a suitable height, the magnetic powder brake 833 is de-energized, and the hammer 831 and the driven shaft 836 are unlocked. Under the action of inertia, it hits the side of the floating platform 500, applying the instantaneous hammering force to the hydroelectric main shaft 400. S5. During steps S3 and S4, the dynamic behavior of the hydroelectric main shaft is detected by the horizontal vibration sensor 871, the vertical vibration sensor 872, the X-axis swing sensor 861, the bracket, and the Y-axis swing sensor 862; the triggering process of the trip unit centrifugal block 405 is recorded by the high-speed camera 201 to evaluate the performance of the trip unit overspeed protection device.

[0031] Furthermore, during steps S3 to S5, if a dangerous situation occurs during the test, the brake caliper 840 is activated to clamp the skirt 601 of the turntable 600, thereby achieving emergency braking of the hydroelectric shaft simulation device. Furthermore, if the main shaft 400 needs to rotate under conditions where it is not subjected to combined loads of X, Y, and Z directional vibration and hammering, the limiting and fixing device 900 shall fix the floating platform 500 and the fixed platform 110 in a fixed connection.

[0032] The embodiments described in this specification are merely examples of implementations of the inventive concept. The scope of protection of this invention should not be considered as limited to the specific forms stated in the embodiments. The scope of protection of this invention also extends to equivalent technical means that can be conceived by those skilled in the art based on the inventive concept.

Claims

1. A full-condition simulation test system for a hydroelectric main shaft, characterized in that, The device includes a fixed platform with a trip start detection device on one side. A hollow triaxial platform, a triaxial excitation system, and a rotary drive unit are mounted on the fixed platform. A hollow floating platform is connected to the moving end of the triaxial platform, and bearings are installed inside the floating platform. The rotary drive unit includes a power unit and a main shaft connected to the torque output end of the power unit. The main shaft passes through the triaxial platform and the bearings in sequence and is then connected to a turntable for transmission. The hydroelectric shaft used for simulation testing is mounted on the turntable. The triaxial excitation system is used to apply high-frequency sinusoidal excitation loads in the X, Y, and Z directions to the hydroelectric shaft mounted on the turntable.

2. The full-condition simulation test system for a hydroelectric main shaft according to claim 1, characterized in that, The hydroelectric main shaft includes a simulated base rod, with adjustable extension rods installed at both ends of the simulated base rod. A tripping centrifugal block is connected to the left adjustable extension rod, and a balancing mass block is connected to the right adjustable extension rod. The simulated base rod is mounted on the turntable by a clamp.

3. The full-condition simulation test system for a hydroelectric main shaft according to claim 1, characterized in that, The trip unit activation detection device includes a ground rail, a trolley mounted on the ground rail, a column fixedly connected to the trolley, a first linear module and a second linear module mounted on the top of the column, a trip unit trigger probe mounted on the moving end of the first linear module, a camera bracket connected to the moving end of the second linear module, and a high-speed camera mounted on the camera bracket.

4. The full-condition simulation test system for a hydroelectric main shaft according to claim 1, characterized in that, The power unit includes a main motor, the output shaft of which is connected to the input shaft of the reducer via a coupling, and the output shaft of the reducer is connected to the lower end of the main shaft via a flexible coupling.

5. The full-condition simulation test system for a hydroelectric main shaft according to claim 1, characterized in that, The hollow floating platform has a double-layer platform structure. The hollow floating platform is supported on the platform of the fixed platform by multiple elastic feet. Each elastic foot is equipped with a limiting and fixing device. The limiting and fixing device includes a shaft tube opened on the hollow floating platform. A support shaft is inserted into the shaft tube. A slot is opened at the upper end of the support shaft. A trapezoidal expansion block is provided in the slot. The expansion block is connected to the slot by a screw. An extrusion block is provided on both sides of the expansion block. The extrusion block cooperates with the inclined surface of the trapezoidal inclined block.

6. The full-condition simulation test system for a hydroelectric main shaft according to claim 1, characterized in that, The three-axis platform includes a hollow guide frame, with multiple Z-axis sliders connected around the guide frame. Z-axis guide rails, assembled inside the Z-axis sliders, are connected to a fixed platform. Multiple X-axis guide rails are installed on the guide frame, and multiple X-axis sliders are assembled on the X-axis guide rails. Y-axis sliders are connected to the X-axis sliders, and multiple Y-axis guide rails are assembled inside the multiple Y-axis sliders. The floating platform is connected to the multiple Y-axis guide rails.

7. A full-condition simulation test system for a hydroelectric main shaft according to any one of claims 1 to 6, characterized in that, The triaxial excitation system includes an X-axis excitation device, a Y-axis excitation device, a Z-axis excitation device, an X-axis sway sensor, and a Y-axis sway sensor. The X-axis and Y-axis excitation devices are mounted on a fixed frame at a 90-degree angle. The X-axis sway sensor is connected to the X-axis excitation device via a right-angle bracket, and the Y-axis sway sensor is connected to the Y-axis excitation device via a right-angle bracket. The triaxial platform is set on the Z-axis excitation device.

8. The full-condition simulation test system for a hydroelectric main shaft according to claim 7, characterized in that, The X-axis excitation device and the Y-axis excitation device have the same structure. The X-axis excitation device includes a support fixedly connected to a fixed frame, a first servo geared motor installed on the support, a cam oscillator connected to the output shaft of the first servo geared motor, a vibration seat on the outer sleeve of the cam oscillator, and the vibration seat connected to one side of the floating frame.

9. The full-condition simulation test system for a hydroelectric main shaft according to claim 8, characterized in that, The Z-axis excitation device includes a hollow oil cylinder and a support plate connected to a fixed frame. A second servo reduction motor and a pilot cylinder are mounted on the support plate. The two chambers of the pilot cylinder are connected to the two chambers of the hollow oil cylinder through hydraulic oil pipes. The output shaft of the second servo reduction motor is connected to the piston rod of the pilot cylinder through a cam reciprocating mechanism.

10. The full-condition simulation test system for a hydroelectric main shaft according to claim 9, characterized in that, It also includes an impact force application system, which includes a hammering device, a horizontal vibration sensor, a vertical vibration sensor, and multiple brake calipers. The hammering device is mounted on a fixed platform and is used to apply a horizontal hammering instantaneous impact load to the water and electricity shaft of the turntable. The horizontal vibration sensor and the vertical vibration sensor are respectively mounted on the side and the lower platform of the floating platform. Each brake caliper is mounted on the floating platform. A skirt is provided around the edge of the turntable, and the skirt is located inside the brake caliper.

11. The full-condition simulation test system for a hydroelectric main shaft according to claim 10, characterized in that, The hammering device includes a support frame mounted on a fixed platform. A third servo motor and a driven shaft are mounted on the support frame. The output shaft of the third servo motor is connected to the driven shaft via a synchronous belt transmission mechanism. A magnetic powder brake is mounted on the driven shaft and is connected to the hammer.

12. A test method using the full-condition simulation test system for hydroelectric main shafts as described in claim 11, characterized in that, Includes the following steps: S1. Based on the required simulated hydraulic shaft diameter specifications, select a suitable hydraulic shaft for the simulation test, fix it on the turntable, and adjust the trip unit to start the detection device to the detection position; S2. The rotary drive unit drives the main shaft of the hydroelectric power plant to rotate at a preset speed, simulating different speed operating conditions; S3. Start the triaxial excitation system to apply high-frequency sinusoidal excitation loads in the X, Y, and Z directions to the main shaft of the hydroelectric power plant; S4. Activate the hammering device to strike the side of the floating platform with a heavy hammer to apply a horizontal hammering instantaneous impact load to the hydroelectric main shaft; S5. During steps S3 and S4, the dynamic behavior of the hydroelectric shaft is detected by horizontal vibration sensor, vertical vibration sensor, X-axis swing sensor and Y-axis swing sensor. The triggering process of the trip unit centrifugal block was recorded by a high-speed camera to evaluate the performance of the trip unit overspeed protection device.

13. The test method of the full-condition simulation test system for hydroelectric main shafts according to claim 12, characterized in that, If a dangerous situation occurs during steps S3 to S5, the brake caliper will be activated to clamp the skirt of the turntable, thereby achieving emergency braking of the hydroelectric shaft simulation device.

14. The test method of the full-condition simulation test system for hydroelectric main shafts according to claim 12, characterized in that, If the main shaft of the hydroelectric system needs to rotate under conditions where it is not subjected to combined loads of X, Y, and Z-axis vibration and hammering, a limiting and fixing device shall be used to fix the floating platform and the fixed platform.

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