A high-frequency vibration table

Abstract

The present invention discloses a high-frequency vibration table, comprising: a vibration table body, including an excitation coil, a moving coil and an induction ring, wherein the moving coil generates vibration through the interaction between the induction ring and the constant magnetic field generated by the excitation coil. The power amplifier system adopts sinusoidal pulse width modulation technology, and controls the power switch to output an amplified sinusoidal signal to drive the moving coil through a logic drive module. The cooling system is used to dissipate heat from the vibration table induction ring and the power amplifier. The center zero position system is used to monitor the position of the moving coil and ensure that the moving coil is always in a balanced position of vibration. By adopting a combined structure of the excitation coil, the moving coil and the induction ring, a more stable vibration output can be achieved through the interaction between the induction ring and the magnetic field. The interaction between the constant magnetic field generated by the excitation coil and the moving coil can flexibly adjust the vibration frequency, so that it can adapt to the vibration test requirements of different frequencies, thereby broadening the application range of the vibration table.

Description

Technical Field

[0001] The present invention relates to the technical field of vibration tables, and in particular to a high-frequency vibration table. Background Art

[0002] Electromagnetic vibration tables are essential testing equipment for the development of aerospace (military) products such as rockets, missiles, and satellites. They are widely used in product strength verification, transportation environment testing, and reliability testing. They are used in product development and verification under simulated operating conditions across various industries, including aerospace, aviation, shipbuilding, automotive, and trains. Vibration testing equipment generates excitation force by driving moving parts through the interaction of alternating current in a drive coil and a constant magnetic field. Electromagnetic vibration tables utilize the principle of electromagnetic induction. They typically have two coils: one fixed to a base and the other to a movable vibration table. When current flows through the fixed coil, the generated magnetic field causes the metal mass on the vibration table to vibrate. The vibration frequency can be controlled by varying the power supply frequency. Because the power supply frequency is very stable, electromagnetic vibration tables offer high precision, stability, and reliability. They are ideal for high-frequency reliability testing of products, such as turbine blades for aircraft engines. Conventional electromagnetic vibration tables, however, experience high-frequency vibrations at frequencies as high as 2500Hz due to signal interference, mechanical instability, and insufficient heat dissipation, making them difficult to meet high-precision testing requirements. Summary of the Invention

[0003] In order to overcome the above shortcomings, the object of the present invention is to provide a high-frequency vibration table to solve the problems raised in the above background technology.

[0004] In order to achieve the above objectives, the technical solution adopted by the present invention is a high-frequency vibration table, characterized in that it includes:

[0005] The vibration table body includes an excitation coil, a moving coil and an induction ring. The moving coil generates vibration through the interaction of the induction ring and the constant magnetic field generated by the excitation coil.

[0006] The power amplifier system adopts sinusoidal pulse width modulation technology, and controls the power switch through the logic drive module to output the amplified sinusoidal signal to drive the dynamic coil.

[0007] The cooling system is used to dissipate heat from the vibration table induction ring and power amplifier.

[0008] The center zero position system is used to monitor the position of the moving coil and ensure that the moving coil is always in a vibration equilibrium position.

[0009] Preferably, the vibration table body adopts an induction structure, the dynamic coil and the induction ring are connected by curing with high-temperature glue, the driving coil is fixed in the magnetic cylinder ring, and the alternating current is induced to the surface of the induction ring through the principle of cylindrical transformer.

[0010] Preferably, the power amplifier system includes:

[0011] The buffer module is used to perform anti-interference processing on the input signal.

[0012] The carrier generator module generates a triangular wave signal with stable frequency.

[0013] The pulse width modulation module combines the buffer output signal and the feedback signal and compares them with the triangular wave to generate a rectangular wave with adjustable duty cycle.

[0014] The logic drive module performs branch delay processing on the PWM signal and adds synchronous pulse protection.

[0015] The isolation buffer module is used to isolate the level of the signal sent from the logic drive part and perform voltage drive or current drive;

[0016] The power switch module adopts a high-speed power semiconductor device with a full-bridge topology, and the output end is connected to the inductive load.

[0017] The filtering module is configured as a low-pass filter having a cutoff frequency lower than the carrier frequency.

[0018] Voltage negative feedback loop to achieve deep voltage negative feedback.

[0019] Preferably, the logic driver module includes:

[0020] The signal splitting unit divides the PWM signal into four driving signals.

[0021] Delay control unit, set 0.1-2μs adjustable delay to prevent bridge arm from shooting through.

[0022] The synchronous pulse injection unit receives the pulse width limit signal to force the switching cycle to reset.

[0023] Preferably, the triangular wave frequency stability generated by the carrier generator module is better than ±0.1%, and the linearity error is less than 1%. The power switch module includes a three-phase full-bridge rectifier unit, a DC bus capacitor group, and four half-bridge power units. The input voltage of the three-phase full-bridge rectifier unit is 380VAC±10%. The DC bus capacitor group is equipped with a voltage-sharing resistor and a bleeder circuit. Each half-bridge of the four half-bridge power units is equipped with an independent drive isolation circuit.

[0024] Preferably, the cooling system includes a deionized water filtration system and a nozzle, which automatically triggers the spray when the driving current exceeds the set current value, and sprays deionized water onto the surface of the induction ring to enhance heat dissipation.

[0025] Preferably, the center zero position system includes a center zero position controller, a photoelectric sensor, an air spring assembly, and a dynamic coil guide assembly. The photoelectric sensor is positioned corresponding to the dynamic coil, and the air spring assembly includes an upper air spring and a lower air spring, respectively, positioned above and below the dynamic coil. The dynamic coil guide system includes a guide shaft and guide bearings, and dynamically adjusts the dynamic coil height via an air spring. Combined with the center zero position controller, it provides displacement and overload protection for the dynamic coil.

[0026] Preferably, the vibration table body further comprises a horizontal slide switching mechanism, which is locked by a trunnion and an air spring and fixed by wall plate screws, and is used for rapid conversion between vertical and horizontal vibration modes.

[0027] Preferably, the high-frequency vibration table further includes a single-point grounding system, which eliminates ground loop interference through an independent grounding wire, and is used to enable the power amplifier system and the vibration controller that outputs the waveform to achieve signal transmission using an isolation transformer.

[0028] Preferably, the vibration table body and the power amplifier are connected via a standardized cable, and the standardized cable includes a dynamic coil wire (O+, O-), an excitation wire (F+, F-) and an interlocking protection wire. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a principle block diagram of a power amplifier system of an embodiment of a high-frequency vibration table of the present invention;

[0030] Figure 2 This is a front schematic diagram of an embodiment of a high-frequency vibration table of the present invention;

[0031] Figure 3 A side view of an embodiment of a high-frequency vibration table according to the present invention, wherein the vibration table is in a vertical vibration mode;

[0032] Figure 4 This is a partial structural diagram of an embodiment of a high-frequency vibration table according to the present invention, wherein the vibration table is in a horizontal vibration mode;

[0033] In the picture:

[0034] 1. Vibration table body; 2. Upper air spring; 3. Lower air spring; 4. Air float; 5. Cable and water pipe connection terminal; 6. Wall panel; 7. Locking screw; 8. Horizontal slide switching mechanism; 9. Connector; 10. Horizontal limit switch; 11. Center indicator; 12. Horizontal slide; 13. Buffer module; 14. Carrier generator module; 15. Pulse width modulation module; 16. Logic drive module; 17. Power switch module; 18. Filter module; 19. Voltage negative feedback loop; 20. Isolation buffer module; 21. Load. DETAILED DESCRIPTION

[0035] The preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more precise definition of the protection scope of the present invention.

[0036] refer to Figures 1 to 4 , Figure 1 A principle block diagram of a power amplifier system of a high-frequency vibration platform provided by an embodiment of the present invention is shown; Figure 2 1. A schematic front view of a high-frequency vibration table provided in an embodiment of the present invention is shown; Figure 3 A schematic side view of a high-frequency vibration table provided by an embodiment of the present invention is shown, wherein the vibration table is in a vertical vibration mode; Figure 4 A partial structural schematic diagram of a high-frequency vibration table provided by an embodiment of the present invention is shown, wherein the vibration table is in a horizontal vibration mode.

[0037] like Figures 1 to 4 As shown, the technical solution provided by this application is a high-frequency vibration table, comprising:

[0038] The vibration table body 1 includes an excitation coil, a moving coil and an induction ring. The moving coil vibrates through the interaction of the induction ring and the constant magnetic field generated by the excitation coil.

[0039] The power amplifier system adopts sinusoidal pulse width modulation technology, and controls the power switch to output an amplified sinusoidal signal to drive the dynamic coil through the logic drive module 16.

[0040] The cooling system is used to dissipate heat from the vibration table induction ring and power amplifier.

[0041] The center zero position system is used to monitor the position of the dynamic coil and keep it in a vibration equilibrium position at all times.

[0042] The high-frequency vibration table provided in this application utilizes a combined structure of an excitation coil, a dynamic coil, and an induction ring. Wall panels 6 are provided on both sides of the vibration table body 1 for support. This structure enables more precise control of vibration generation and transmission. The interaction between the induction ring and the magnetic field enables a more stable vibration output. The interaction between the constant magnetic field generated by the excitation coil and the dynamic coil allows for flexible adjustment of the vibration frequency, enabling it to adapt to vibration testing requirements of varying frequencies and broadening the application range of the vibration table. Sine pulse width modulation (SPWM) technology generates high-quality sinusoidal signals with minimal waveform distortion and low harmonic content, providing a purer and more stable drive signal for the dynamic coil, making the vibration of the vibration table more stable and uniform, and improving the accuracy of test results. The center zero position system monitors and adjusts the position of the dynamic coil to ensure it is always in a balanced position, effectively reducing offset and error during the vibration process and improving the accuracy and stability of the vibration.

[0043] In some embodiments, reference Figures 1 to 4 The vibration table body 1 adopts an induction structure. The dynamic coil and the induction ring are connected by high-temperature glue. The driving coil is fixed in the magnetic cylinder ring. The alternating current is induced to the surface of the induction ring through the principle of cylindrical transformer.

[0044] For example, the dynamic coil and the induction ring are driven by electromagnetic induction without direct contact. At the same time, the high-temperature glue can maintain good bonding performance in a high-temperature environment. The cured connection of the high-temperature glue can distribute stress more evenly, avoiding structural damage caused by stress concentration at the connection point, and enhancing the fatigue resistance of the vibration table.

[0045] It ensures that the moving coil and the induction ring will not loosen or fall off during vibration, which improves the stability of the structure, especially under high-frequency vibration and high-temperature working conditions.

[0046] In some embodiments, reference Figures 1 to 4 , the power amplifier system includes:

[0047] Buffer module 13, used for performing anti-interference processing on input signals;

[0048] The carrier generator module 14 generates a triangular wave signal with a stable frequency;

[0049] The pulse width modulation module 15 combines the buffer output signal and the feedback signal and compares them with the triangular wave to generate a rectangular wave with adjustable duty cycle;

[0050] The logic drive module 16 performs branch delay processing on the PWM signal and adds synchronous pulse protection;

[0051] The isolation buffer module 20 is used to isolate the level of the signal sent from the logic drive part and perform voltage drive or current drive;

[0052] The power switch module 17 adopts a high-speed power semiconductor device with a full-bridge topology, and the output end is connected to the inductive load 21;

[0053] The filtering module 18 is configured as a low-pass filter having a cut-off frequency lower than the carrier frequency;

[0054] The voltage negative feedback loop 19 realizes deep voltage negative feedback.

[0055] For example, the logic driver module 16 is mainly responsible for receiving the pulse wave transmitted by the pulse width modulation module 15. Within this module, the pulse wave will be distributed to twelve different channels. In actual applications, power devices are not switches in an ideal state, and there is a certain delay in their switching action, namely, rise time and fall time. In order to avoid the undesirable situation where the power switches on the same bridge arm are turned on at the same time, the pulse waves distributed to the twelve channels are all set with corresponding dead time. The length of the dead time is determined by the switching time of the power switch. Under the premise of ensuring that the power switches will not be turned on together, the shorter the dead time, the more conducive it is to ensuring the accuracy of the signal, otherwise the sine wave obtained after demodulation will be significantly distorted.

[0056] To prevent excessive signal strength in the input buffer, which could cause the carrier signal to lose its intersection with the input signal and potentially cause the power switch to remain on for extended periods, the logic driver also receives synchronization pulses from the pulse-width limiter. This design ensures that the power switch can continue to turn on and off at the specified switching frequency even if a PWM failure occurs, effectively protecting the power device from damage caused by abnormal conditions.

[0057] The power switches utilize a full-bridge switching structure, with each switch requiring an independent and relatively independent drive signal. The isolation buffer section is responsible for level-isolating the signals output by the logic driver section. Whether to use voltage or current drive is determined by the specific characteristics of the power switches. The isolation buffer section must exhibit strong immunity to common-mode interference to ensure stable signal transmission. Furthermore, signal transmission delay must be minimized to improve system response speed. Furthermore, it must have low dynamic internal resistance to minimize energy loss. More importantly, it must provide reliable protection against transient overcurrent and short-circuit faults in the power devices. The performance of the isolation buffer section is directly related to the conversion efficiency of the switching power amplifier, making it a key factor influencing overall system efficiency.

[0058] The power switch section amplifies the sinusoidal width modulated pulses sent from the isolation buffer section. Operating in a switching state, this section requires a wide safe operating area and high short-circuit capacity for high frequencies, high speeds, and high currents. Power devices are typically power field-effect transistors (MOSFETs) or power field-effect modules (MOSFETs), depending on the power output. Because the load characteristics of the electric stage are inductive, overvoltage is generated when the power switch is turned off. Excessive overvoltage can damage the power switch and must therefore be suppressed. Two common approaches are to add an absorption (snubber) circuit to the power switch; or to minimize the wiring connecting the power switch during layout.

[0059] The filtering component converts the high-power discrete pulses sent by the power switch into a continuous (current) voltage output. The requirements for this component are to effectively suppress the carrier signal while not attenuating the modulated signal. Furthermore, it must have a high quality factor. Generally, the electrodynamic shaker is driven by a constant voltage, which requires the power amplifier to have a low output impedance. To achieve this, the power amplifier incorporates deep negative voltage feedback to ensure a constant output voltage despite fluctuations in the grid voltage and changes in the vibration frequency, which cause changes in the shaker's impedance.

[0060] In some embodiments, reference Figures 1 to 4 , the logic driver module 16 includes:

[0061] The signal splitting unit divides the PWM signal into four driving signals.

[0062] Delay control unit, set 0.1-2μs adjustable delay to prevent bridge arm from shooting through.

[0063] The synchronous pulse injection unit receives the pulse width limit signal to force the switching cycle to reset.

[0064] For example, in a full-bridge topology, shoot-through (i.e., simultaneous conduction of the upper and lower bridge arms) can cause a power short circuit and damage power devices. By setting an adjustable delay, sufficient time interval is ensured between the switching actions of the upper and lower bridge arms to prevent shoot-through. The adjustable delay range of 0.1-2μs meets the requirements of different operating frequencies and load conditions, providing high-precision control capabilities and ensuring reliability in high-frequency switching applications. By receiving a pulse width limit signal and forcing a switching cycle reset, switching errors caused by abnormal pulses or signal interference can be effectively avoided, ensuring that the power switching devices operate in a safe operating state.

[0065] The logic module uses unipolar frequency-doubling modulation to increase the output PWM switching frequency, thereby reducing the burden on the inverter main circuit. Unlike bipolar PWM modulation, unipolar frequency-doubling modulation uses two reference sine waves of opposite polarity to intersect a bidirectional triangle wave to generate the power switch drive signal. This doubles the frequency of the output voltage between the midpoints of the main circuit bridge arms without changing the IGBT switching frequency, thereby reducing switching losses, reducing the size of the output filter, and improving waveform quality.

[0066] Another function of the logic module is to monitor the system, providing protection not only for the switching power amplifier itself but also for overtravel of the vibration table's moving system and overheating of the vibration table's heat-generating components. A set of fault indicators indicates the nature of the fault. When any fault indicator illuminates, the input excitation signal is automatically blocked by the interlock protection system. Furthermore, to dissipate most of the heat stored within the table during shutdown, a cooling delay shutdown circuit, typically with a five-minute delay, is implemented. The excitation power supply is derived from the main power supply, which is then stepped down and rectified by the excitation transformer to provide the DC excitation current for the vibration table's excitation coil. Due to the energy storage function of the excitation coil, this power supply provides excitation discharge protection to prevent overvoltage when the coil is de-energized. This protection also includes excitation power supply overheating protection.

[0067] The power module uses a single-axis pulse width modulation amplifier (PCI) and operates in voltage mode. Its rated current is 100 A rms and 400 A peak. It is powered by a 300 V DC power supply. When a sinusoidal input signal is used, each half-bridge can be sinusoidally modulated, so that the duty cycle varies at a sinusoidal frequency, and each end outputs a different phase, resulting in an amplified sinusoidal signal at the output.

[0068] In some embodiments, reference Figures 1 to 4 The triangular wave frequency stability generated by carrier generator module 14 is better than ±0.1%, and the linearity error is less than 1%. Power switch module 17 includes a three-phase full-bridge rectifier unit, a DC bus capacitor bank, and four half-bridge power units. The input voltage of the three-phase full-bridge rectifier unit is 380VAC ±10%. The DC bus capacitor bank is equipped with a voltage-equalizing resistor and a bleeder circuit. Each half-bridge of the four half-bridge power units is equipped with an independent drive isolation circuit.

[0069] For example, a triangular wave carrier signal with a frequency stability better than ±0.1% provides an extremely stable reference for pulse-width modulation (PWM). This high-precision carrier signal ensures more precise control of the PWM signal's duty cycle, thereby improving the output signal quality of the power amplifier system and reducing output voltage or current instability caused by carrier frequency fluctuations.

[0070] In some embodiments, reference Figures 1 to 4 The cooling system includes a deionized water filtration system and a nozzle. When the driving current exceeds the set current value, the spray is automatically triggered to spray deionized water onto the surface of the induction ring to enhance heat dissipation.

[0071] For example, deionized water has high thermal conductivity and specific heat capacity, allowing it to quickly absorb and conduct heat. Compared to traditional air cooling or other cooling media, it can more effectively reduce the temperature of the induction ring surface. The nozzle can evenly spray deionized water onto the induction ring surface, creating a large cooling contact area, quickly dissipating heat generated by the induction ring and significantly improving heat dissipation efficiency. The cooling system also includes corresponding cable and water pipe connection terminals 5 for connecting to the deionized water filtration system and the nozzle, respectively.

[0072] During operation, the induction loop generates significant heat due to the induced current. To address this heat dissipation issue, the vibration table's air ducts are optimized, utilizing a high-efficiency exhaust fan to quickly remove this heat, allowing the internal temperature to reach equilibrium. To reduce the surface temperature of the induction loop and improve heat dissipation during high-speed, high-acceleration, and extended operation, a spray switch is activated when the drive current exceeds 375A. The spray water is sourced from mains water, which undergoes a series of deionization treatments, including primary and secondary filtration and a mixed bed, to achieve an outlet resistivity of 1-18 MΩ·CM. This water is then sprayed through a nozzle onto the magnetic gap, rapidly cooling the surface temperature of the induction loop.

[0073] In some embodiments, reference Figures 1 to 4 The center zero position system includes a center zero position controller, a photoelectric sensor, an air spring assembly, and a dynamic coil guide assembly. The photoelectric sensor is positioned corresponding to the dynamic coil. The air spring assembly includes an upper air spring 2 and a lower air spring 3, located on the upper and lower sides of the dynamic coil, respectively. The dynamic coil guide system includes a guide shaft and guide bearings. The air spring dynamically adjusts the dynamic coil height, and combined with the center zero position controller, it provides displacement and overload protection for the dynamic coil.

[0074] For example, a photoelectric sensor can accurately monitor the position changes of the dynamic coil in real time, providing highly accurate displacement feedback signals. Based on these signals, a center zero position controller can adjust the dynamic coil's position in real time, ensuring it remains in a balanced vibration position, thereby improving the vibration table's accuracy and stability. An air float 4 is installed at the bottom of the vibration table body 1, connected to pipelines for air supply to the upper and lower air springs 2 and 3, respectively.

[0075] During operation, the center zero position system of an electric vibrator ensures that the dynamic coil remains in its equilibrium position, or zero position. The center zero position system uses a pair of photoelectric sensors to instantly detect the dynamic coil's position and provide feedback to the center zero position system, which then replenishes or deflates the air spring beneath the dynamic coil. The center zero position automatically adjusts the air pressure in the air spring according to the load. The position control system consists of dual proximity sensors and a reflector. The photoelectric sensors provide a feedback loop for dynamic coil position. The dual proximity sensors are mounted on the platform, while the reflector is mounted on the dynamic coil. As the dynamic coil moves up and down, the shape of the reflective markers causes the two sensors to reflect different positions. The vibration platform's sensors then determine the center position. During normal operation, the center zero position system uses this feedback to adjust the pressure in the air spring beneath the dynamic coil in real time.

[0076] In some embodiments, reference Figures 1 to 4 The vibration table body 1 also includes a horizontal slide switching mechanism 8, which is locked by the ear shaft and air spring and fixed with screws on the wall plate 6, and is used for rapid conversion between vertical and horizontal vibration modes.

[0077] For example, traditional vibration tables usually require complex mechanical adjustments or reassembly to switch between vertical and horizontal vibration modes, which is time-consuming and labor-intensive. The ear shaft air spring lock can provide high-precision positioning capabilities, ensuring that the horizontal slide 12 can be accurately fixed in the required position during the switching process, reducing vibration deviations caused by inaccurate positioning. The efficiency of equipment use is greatly improved. The slide switching mechanism includes a center indicator 11, a horizontal limit switch 10 and a connector 9. The center indicator 11 is located on the side of the horizontal slide 12 of the vibration table, and is used to detect the vibration position of the table surface and determine whether the horizontal slide 12 is in the middle position. The horizontal limit switch 10 works through a mechanical trigger mechanism. When the object to be detected reaches the preset position, the mechanical structure in the switch is subjected to external force, and the contacts are triggered, thereby generating a switch signal. The connector 9 is used to connect to the circuit of the vibration table body 1.

[0078] The vibration table 1 can be connected to a hydrostatic bearing horizontal slide 12 or a V-track horizontal slide 12 to meet the user's requirements for horizontal vibration testing. The horizontal slide 12 can be either integrated or split. The split horizontal slide is also called an independent horizontal slide. The lower portion of the horizontal slide is supported by non-deformable granite material as a hydrostatic support. The vibration table 1 is equipped with guide trunnions and air springs. The air springs are located within the trunnions and have an air supply pressure of 0.69 MPa. During horizontal vibration, the table's mechanical position can be adjusted using four trunnion air springs. The trunnions are equipped with locking screws 7 that restrict the table's free movement during equipment transportation. The four trunnion air springs dampen the table's vibrations during operation, allowing the table to vibrate along the trunnion guide axis. The stiffness of the air springs is adjusted by the air pressure in the airbags, and the control valve is located at the center zero position of the table's edge.

[0079] In some embodiments, reference Figures 1 to 4 The high-frequency vibration table also includes a single-point grounding system, which eliminates ground loop interference through an independent grounding wire, and is used to enable the power amplifier system and the vibration controller that outputs the waveform to use an isolation transformer to achieve signal transmission.

[0080] For example, by eliminating ground loop interference, the single-point grounding system can significantly improve the purity and stability of the signal, reduce the impact of noise and interference on the vibration control signal, and thus improve the control accuracy and reliability of the vibration table. The isolation transformer can achieve electrical isolation between the power amplifier system and the vibration controller, preventing high-voltage or high-current signals from interfering with the control signal through the ground path, thereby protecting the control equipment from damage. For a single-point grounding solution. Even if current passes through the ground wire, single-point grounding does not generate impedance for the circuit connected to that point. In contrast, for a multi-point grounding system, a potential difference may occur between different grounding points. The potential difference generated by multi-point grounding may be mixed in different instruments and control circuits and is difficult to distinguish.

[0081] In some embodiments, reference Figures 1 to 4 The vibration table 1 is connected to the power amplifier through standardized cables, which include dynamic cables (O+, O-), excitation cables (F+, F-) and interlocking protection cables.

[0082] For example, separating the dynamic and excitation cables reduces signal interference. The dynamic cables (O+, O-) are specifically used to transmit drive signals, while the excitation cables (F+, F-) provide excitation current. This clear functional division improves signal transmission quality and stability, reducing noise and interference. When a system fault occurs, this clear functional division makes troubleshooting easier. Operators can quickly identify the problem based on the cable's function, determining whether it's a drive signal issue or an excitation current issue, thereby improving troubleshooting efficiency.

[0083] The above embodiments are only for illustrating the technical concept and features of the present invention. Its purpose is to enable people familiar with this technology to understand the content of the present invention and implement it. It cannot be used to limit the scope of protection of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A high frequency vibration table, characterized in that, include: The vibration table body includes an excitation coil, a moving coil and an induction ring. The moving coil vibrates through the interaction of the induction ring and the constant magnetic field generated by the excitation coil; The power amplifier system uses sinusoidal pulse width modulation technology to control the power switch through the logic drive module to output the amplified sinusoidal signal to drive the dynamic coil; Cooling system, used to dissipate heat from the vibration table induction ring and power amplifier; A center zero position system is used to monitor the position of the moving coil and ensure that the moving coil is always in a vibration equilibrium position; The power amplifier system comprises: Buffer module, used for anti-interference processing of input signals; Carrier generator module, generates a triangular wave signal with stable frequency; The pulse width modulation module combines the buffer output signal with the feedback signal and compares it with the triangular wave to generate a rectangular wave with adjustable duty cycle; Logic drive module, which performs branch delay processing on PWM signal and adds synchronous pulse protection; The isolation buffer module is used to isolate the level of the signal sent from the logic drive part and perform voltage drive or current drive; The power switch module adopts a high-speed power semiconductor device with a full-bridge topology, and the output end is connected to the inductive load; A filtering module configured as a low-pass filter having a cutoff frequency lower than the carrier frequency; Voltage negative feedback loop to achieve deep voltage negative feedback; The triangular wave frequency stability generated by the carrier generator module is better than ±0.1%, and the linearity error is less than 1%. The power switch module includes a three-phase full-bridge rectifier unit, a DC bus capacitor group, and four half-bridge power units. The input voltage of the three-phase full-bridge rectifier unit is 380VAC±10%. The DC bus capacitor group is equipped with a voltage-sharing resistor and a bleeder circuit. Each half-bridge of the four half-bridge power units is equipped with an independent drive isolation circuit. The logic driver module includes: Signal splitting unit, which divides the PWM signal into four driving signals; Delay control unit, set 0.1-2μs adjustable delay to prevent bridge arm from passing through; The synchronous pulse injection unit receives the pulse width limit signal to force the switching cycle to reset.

2. The high frequency vibration table according to claim 1, characterized in that: The vibration table adopts an induction structure, the dynamic coil and the induction ring are connected by curing with high-temperature glue, the driving coil is fixed in the magnetic cylinder ring, and the alternating current is induced to the surface of the induction ring through the principle of cylindrical transformer.

3. The high frequency vibration table according to claim 1, characterized in that: The cooling system includes a deionized water filtration system and a nozzle, which automatically triggers the spray when the driving current exceeds the set current value, spraying deionized water onto the surface of the induction ring to enhance heat dissipation.

4. The high frequency vibration table according to claim 1, characterized in that: The center zero position system includes a center zero position controller, a photoelectric sensor, an air spring assembly and a moving coil guide assembly. The photoelectric sensor is arranged corresponding to the moving coil. The air spring assembly includes an upper air spring and a lower air spring respectively arranged on the upper and lower sides of the moving coil; the moving coil guide system includes a guide shaft and a guide bearing, and dynamically adjusts the height of the moving coil through the air spring, and combines with the center zero position controller to realize displacement and overload protection of the moving coil.

5. The high frequency vibration table according to claim 1, characterized in that: The vibration table body also includes a horizontal slide switching mechanism, which is locked by a trunnion and an air spring and fixed by wall plate screws, and is used for rapid conversion between vertical and horizontal vibration modes.

6. The high frequency vibration table according to claim 1, characterized in that: It also includes a single-point grounding system that eliminates ground loop interference through an independent grounding wire, and is used to enable the power amplifier system and the vibration controller that outputs the waveform to achieve signal transmission using an isolation transformer.

7. The high frequency vibration table according to claim 1, characterized in that: The vibration table body and the power amplifier are connected via a standardized cable, which includes a dynamic coil wire (O+, O-), an excitation wire (F+, F-) and an interlocking protection wire.

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