Rapid tracking method for resonant frequency of ultrasonic transducer

Abstract

The invention provides a method for rapidly tracking the resonant frequency of an ultrasonic transducer, which is a method for rapidly tracking the resonant frequency of the ultrasonic transducer according to a rapid tracking device, and comprises the following steps of: sampling a voltage signal and a current signal of the ultrasonic transducer; preprocessing the voltage signal and the current signal and outputting a preprocessed signal; and calculating a first amplitude of the voltage signal, a second amplitude of the current signal and a phase difference between the voltage signal and the current signal based on the preprocessed signal, and controlling ultrasonic output of the ultrasonic transducer based on the first amplitude, the second amplitude and the phase difference. According to the invention, the method for rapidly tracking the resonant frequency of the ultrasonic transducer can improve the tracking speed and accuracy.

Description

Technical Field

[0001] The present invention belongs to the technical field of signal processing, and in particular relates to a method for quickly tracking the resonant frequency of an ultrasonic transducer. Background Art

[0002] Ultrasonic generator is a commonly used device, and its core function is to emit ultrasonic waves of a specific frequency through a transducer. In order to ensure the output quality of ultrasonic waves, it is necessary to track the resonant frequency of the transducer in real time to ensure the stability of the output power and frequency of the ultrasonic waves. At the same time, in high-performance equipment such as wire bonding machines, the tracking speed and accuracy of the ultrasonic generator are required to be high.

[0003] There are two existing technical solutions for tracking the resonant frequency of the transducer. The first is to rectify and filter the transducer feedback signal through the circuit, and then send the effective value of the signal to the MCU through the AD. The MCU tracks the resonant frequency of the transducer through the maximum current method. The second is to use the zero-crossing detection circuit, and the FPGA compares the zero-crossing time difference of the feedback signal to find and track the resonant frequency of the transducer.

[0004] There are some problems with the existing technical solutions. First, the DC signal coming out of the rectifier and filter circuit on the circuit is delayed, and there is interference from other frequency noises, resulting in inaccurate resonant frequency. Secondly, through the zero-crossing circuit detection, when there is noise interference in the signal, especially when the signal fluctuates at the zero-crossing point, it will affect the judgment of the software, resulting in inaccurate resonant frequency. In addition, the existing technical solutions cannot meet the requirements of high-performance equipment such as wire welding machines in terms of tracking speed and accuracy. Therefore, a new technical solution is needed to optimize the speed and accuracy of the ultrasonic generator tracking the resonant frequency of the transducer. Summary of the invention

[0005] The present invention aims to solve the defects in the above-mentioned prior art and provide a method for fast tracking of the resonant frequency of an ultrasonic transducer which can improve the tracking speed and accuracy.

[0006] The present invention provides a method for quickly tracking the resonant frequency of an ultrasonic transducer. The method is a method for quickly tracking the resonant frequency of an ultrasonic transducer based on a fast tracking device, comprising: sampling a voltage signal and a current signal of the ultrasonic transducer; preprocessing the voltage signal and the current signal and outputting a preprocessed signal; calculating a first amplitude of the voltage signal, a second amplitude of the current signal, and a phase difference between the voltage signal and the current signal based on the preprocessed signal, and controlling the ultrasonic output of the ultrasonic transducer based on the first amplitude, the second amplitude and the phase difference.

[0007] In the present invention, the above-mentioned data processing method can obtain the complete ultrasonic output signal of the ultrasonic transducer in a short time, thereby speeding up the tracking speed of the resonant frequency. Compared with the prior art, the data processing method of the present invention is more efficient and can complete the tracking of the resonant frequency in a shorter time, thereby meeting the needs of high-performance equipment; in addition, the signal processing method of the present invention of first preprocessing and then further calculating can effectively reduce noise interference and improve the tracking accuracy of the ultrasonic output signal of the ultrasonic transducer. Compared with the method of detecting through a rectifier filtering circuit or a zero-crossing circuit in the prior art, the sampling method of the present invention is more accurate and can better eliminate noise interference, thereby improving the accuracy of the resonant frequency.

[0008] In the method for quickly tracking the resonant frequency of an ultrasonic transducer involved in the present invention, optionally, the preprocessed signal is non-full-cycle data about the voltage signal and the current signal, the non-full-cycle data is processed into full-cycle data, and the first amplitude, the second amplitude, and the phase difference are calculated based on the full-cycle data.

[0009] In the method for quickly tracking the resonant frequency of an ultrasonic transducer involved in the present invention, optionally, after the non-full-cycle data is collected, the non-full-cycle data is written into a memory; the non-full-cycle data in the memory is read and the non-full-cycle data is processed into the full-cycle data.

[0010] In the method for quickly tracking the resonant frequency of an ultrasonic transducer involved in the present invention, optionally, the full-cycle data is a complete sine wave or cosine wave, and the non-full-cycle data is an incomplete sine wave or cosine wave.

[0011] In the method for quickly tracking the resonant frequency of an ultrasonic transducer involved in the present invention, optionally, a first output value is calculated based on the first amplitude and the second amplitude, and the ultrasonic output of the ultrasonic transducer is controlled based on the first output value; a second output value is calculated based on the phase difference, and the ultrasonic output of the ultrasonic transducer is controlled based on the second output value.

[0012] In the method for fast tracking the resonant frequency of an ultrasonic transducer involved in the present invention, optionally, the initial frequencies of the voltage signal and the current signal are determined, and the voltage signal and the current signal are sampled at a high speed based on the initial frequencies.

[0013] In the method for fast tracking the resonant frequency of an ultrasonic transducer involved in the present invention, optionally, FFT calculation is performed to obtain the first amplitude of the voltage signal, the second amplitude of the current signal, and the phase difference between the voltage signal and the current signal.

[0014] In the method for quickly tracking the resonant frequency of an ultrasonic transducer involved in the present invention, optionally, a PID calculation is performed based on the first amplitude and the second amplitude to obtain the first output value.

[0015] In the method for fast tracking the resonant frequency of an ultrasonic transducer involved in the present invention, optionally, the second output value is calculated based on the phase difference by using a dichotomy method and a frequency fine-tuning algorithm.

[0016] In the method for fast tracking the resonant frequency of the ultrasonic transducer involved in the present invention, optionally, the calculation method for calculating the second output value by the dichotomy method and the frequency fine-tuning algorithm may include the following steps: the first step is to determine whether the flag bit of the FFT calculation result is refreshed, if not refreshed, return to re-determine, if refreshed, execute the second step; the second step is to determine whether the phase difference is greater than the preset angle, if not greater than the preset angle, execute the third step, if greater than the preset angle, execute the fourth step; the third step is to determine whether the phase current leads the voltage, if not, execute the fifth step, if yes, execute the sixth step; the fourth step is to determine whether the phase current leads the voltage, if yes, execute the seventh step, if no, execute the eighth step; the fifth step, that is, when the phase difference is not greater than the preset angle, if the phase current does not lead the voltage, then the current frequency f=f-1; the sixth step, that is, when the phase difference is not greater than the preset angle, if the phase current leads the voltage, then the current frequency f=f+1; the seventh step, that is, when the phase difference is greater than the preset angle, if the phase current leads the voltage, then the current frequency f=(f+f _max ) / 2; Step 8, that is, when the phase difference is greater than the preset angle, if the phase current does not lead the voltage, the current frequency f=(f+f _min ) / 2.

[0017] According to the present invention, a method for quickly tracking the resonant frequency of an ultrasonic transducer with improved tracking speed and accuracy can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the description are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 It is a flow chart of a device for quickly tracking the resonant frequency of an ultrasonic transducer involved in an embodiment of the present invention.

[0020] Figure 2It is a flow chart of a method for calculating a second output value using a binary division method and a frequency fine-tuning algorithm according to an embodiment of the present invention.

[0021] Figure 3 It is a functional module diagram of Example 1 of the ultrasonic drive system involved in the embodiment of the present invention.

[0022] Figure 4 It is a functional module diagram of the ultrasonic drive system embodiment 2 involved in the embodiment of the present invention. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the invention clearer, the technical solution in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0024] The present invention also provides a method for quickly tracking the resonant frequency of an ultrasonic transducer (hereinafter referred to as the fast tracking method).

[0025] In some embodiments, the fast tracking method may include step S100, sampling the voltage signal and the current signal of the ultrasonic transducer 20. Specifically, the sampling module 13 samples the voltage signal and the current signal of the ultrasonic transducer 20.

[0026] In some embodiments, the fast tracking method may include step S200, preprocessing the voltage signal and the current signal and outputting the preprocessed signal. Specifically, the first preprocessing module 110 in the first processor 10 preprocesses the voltage signal and the current signal and outputs the preprocessed signal.

[0027] In some embodiments, the fast tracking method may include step S300, calculating a first amplitude of the voltage signal, a second amplitude of the current signal, and a phase difference between the voltage signal and the current signal based on the preprocessed signal, and controlling the ultrasonic output of the ultrasonic transducer based on the first amplitude, the second amplitude, and the phase difference. Specifically, the calculation module 120 in the second processor 12 calculates the first amplitude of the voltage signal, the second amplitude of the current signal, and the phase difference between the voltage signal and the current signal based on the preprocessed signal. The calculation module 120 controls the ultrasonic output of the ultrasonic transducer based on the first amplitude, the second amplitude, and the phase difference.

[0028] In the present invention, the above-mentioned data processing method can obtain the complete ultrasonic output signal of the ultrasonic transducer in a short time, thereby speeding up the tracking speed of the resonant frequency. Compared with the prior art, the data processing method of the present invention is more efficient and can complete the tracking of the resonant frequency in a shorter time, thereby meeting the needs of high-performance equipment; in addition, the signal processing method of the present invention of first preprocessing and then further calculating can effectively reduce noise interference and improve the tracking accuracy of the ultrasonic output signal of the ultrasonic transducer. Compared with the method of detecting through a rectifier filtering circuit or a zero-crossing circuit in the prior art, the sampling method of the present invention is more accurate and can better eliminate noise interference, thereby improving the accuracy of the resonant frequency.

[0029] In some embodiments, the first processor 11 may be an FPGA. The second processor 12 may be a DSP. The sampling module 13 may be an ADC, which is used to sample the analog signal output by the ultrasonic transducer 20 and convert it into a digital signal that can be recognized by the first processor 10. The present invention uses FPGA+DSP+high-speed AD to sample the ultrasonic output signal of the ultrasonic transducer, and the sampling rate can be greater than 10 times the frequency of the ultrasonic output signal. This method can effectively reduce the delay caused by the rectification and filtering circuit on the circuit and the interference of other frequency noises, and improve the accuracy of the resonant frequency.

[0030] In some embodiments, step S300 may include processing the non-full cycle data into full cycle data, and calculating the first amplitude, the second amplitude, and the phase difference based on the full cycle data. Specifically, the second pre-processing module 121 may be configured to process the non-full cycle data into full cycle data. The calculation module 120 may be configured to calculate the first amplitude, the second amplitude, and the phase difference based on the full cycle data.

[0031] In some embodiments, the fast tracking device may further include a memory 14. The memory 14 may be a shared memory of the first processor 11 and the second processor 12. In some embodiments, the memory 14 may be a RAM, a ROM, a FLASH, and the like.

[0032] In some embodiments, the fast tracking method may further include, after collecting the non-full cycle data, writing the non-full cycle data into the memory 14. Specifically, after collecting the non-full cycle data, the first pre-processing module 110 in the first processor 11 may write the non-full cycle data into the memory 14.

[0033] In some embodiments, the fast tracking method may further include reading the non-full cycle data in the memory 14 and processing the non-full cycle data into full cycle data. Specifically, the second pre-processing module 121 of the second processor 12 may read the non-full cycle data in the memory 14 and process the non-full cycle data into full cycle data.

[0034] In some embodiments, the signals processed by the first processor 11 and the second processor 12 may be sine wave signals or cosine wave signals. Full-cycle data may be a complete sine wave or cosine wave, and correspondingly, a non-full-cycle signal may be an incomplete sine wave or cosine wave.

[0035] In some embodiments, the non-full-period signal may be half a sine wave or a cosine wave, a quarter of a sine wave or a cosine wave, etc. It is understandable that due to the regularity of the sine wave or the cosine wave, the second pre-processing module 121 can conveniently supplement the non-full-period signal of the sine wave or the cosine wave into a full-period signal.

[0036] In some embodiments, step S300 may include calculating a first output value based on the first amplitude and the second amplitude, and controlling the ultrasonic output of the ultrasonic transducer 20 based on the first output value. Specifically, the first calculation module 120a may calculate the first output value based on the first amplitude and the second amplitude, and control the amplifier to control the ultrasonic output of the ultrasonic transducer 20 based on the first output value. Here, the ultrasonic output of the ultrasonic transducer 20 may be the output power of the ultrasonic output signal of the ultrasonic transducer 20.

[0037] In some embodiments, step S300 may include calculating a second output value based on the phase difference, and controlling the ultrasonic output of the ultrasonic transducer based on the second output value. In some embodiments, the second output value may be output to the first processor 11, and the first processor 11 may control the ultrasonic output of the ultrasonic transducer based on the second output value. Specifically, the second calculation module 120b may be configured to calculate the second output value based on the phase difference, and output the second output value to the first processor 11. The first processor 11 may control the ultrasonic output of the ultrasonic transducer based on the second output value. Here, the ultrasonic output of the ultrasonic transducer 20 may be the output frequency of the ultrasonic output signal of the ultrasonic transducer 20.

[0038] In some embodiments, the fast tracking method may further include determining the initial frequency (or calibration frequency) of the voltage signal and the current signal, and performing high-speed sampling on the voltage signal and the current signal based on the initial frequency. In some embodiments, the initial frequency may be transmitted to the first processor 11, and the first processor 11 may control the sampling module 13 to perform high-speed sampling based on the initial frequency. Specifically, the second processor 12 determines the initial frequency (or calibration frequency) of the voltage signal and the current signal, and the second processor 12 may transmit the initial frequency to the first processor 11, and the first processor 11 may control the sampling module 13 to perform high-speed sampling based on the initial frequency.

[0039] In some embodiments, the fast tracking device 10 further includes a waveform generator 111 and a converter 15. The first processor 11 can convert the waveform generated signal through the waveform generator 111 through the converter 15 and output it to the ultrasonic transducer.

[0040] In some embodiments, the waveform generator 111 may be a DDS (Direct Digital Synthesis) or may be integrated into the first processor 11 .

[0041] In some embodiments, the converter 14 may be a DAC, which is used to convert a digital signal into an analog signal and output it to the ultrasonic transducer 20 .

[0042] In some embodiments, an FFT (Fast Fourier Transform) calculation may be performed to obtain a first amplitude of the voltage signal, a second amplitude of the current signal, and a phase difference between the voltage signal and the current signal. Specifically, the calculation module 120 may perform an FFT (Fast Fourier Transform) calculation to obtain a first amplitude of the voltage signal, a second amplitude of the current signal, and a phase difference between the voltage signal and the current signal.

[0043] In some embodiments, the fast tracking device 10 may further include a DAC multiplier 16. The DAC multiplier 16 may control the ultrasonic output of the ultrasonic transducer 20 based on the first output value.

[0044] In some embodiments, the fast tracking device 10 may further include a power amplifier circuit 17. One end of the power amplifier circuit 17 may be connected to the DAC multiplier 16, and the other end may be connected to the ultrasonic transducer 20. The power amplifier circuit 17 may amplify the control signal and output it to the ultrasonic transducer 20.

[0045] In some embodiments, the fast tracking method may include performing a PID calculation based on the first amplitude and the second amplitude to obtain a first output value. Specifically, the first calculation module 120a may perform a PID calculation based on the first amplitude and the second amplitude to obtain a first output value. The first output value may be the output value of the DAC multiplier 16 in the next cycle. In this case, the present invention performs a PID calculation through a DSP to determine the value of the DAC multiplier in the next cycle, and is controlled by the DSP to achieve constant ultrasonic output. This control method can accurately adjust the ultrasonic output power to keep it stable. Compared with the prior art, the control method of the present invention is more accurate and can effectively improve the stability of the ultrasonic output power.

[0046] In some embodiments, the fast tracking method may include calculating the second output value based on the phase difference through a binary method and a frequency fine-tuning algorithm. Specifically, the second calculation module 120b can calculate the second output value based on the phase difference through a binary method and a frequency fine-tuning algorithm. The second output value can be the output frequency of the next cycle. In this case, the present invention tracks the resonant frequency of the transducer by combining a binary method and a frequency fine-tuning method. When the phase difference of the current and voltage signals is greater than a preset angle, the frequency of the next cycle is determined by a binary method based on the phase difference leading or lagging judgment. When the current and voltage phase difference is less than a preset angle, the ultrasonic frequency of the next cycle is fine-tuned (for example, plus 1 or minus 1) based on the phase difference leading or lagging judgment. This algorithm combines the advantages of binary method and frequency fine-tuning, and can accurately track the resonant frequency of the transducer under different circumstances. Compared with the prior art, the algorithm of the present invention is more optimized and can adapt to more complex working conditions, thereby improving the tracking accuracy and speed of the resonant frequency.

[0047] The method for calculating the second output value by using the binary method and the frequency fine-tuning algorithm may include the following steps.

[0048] The first step is to determine whether the flag bit of the FFT calculation result is refreshed. If not, return to re-judge. If refreshed, execute the second step.

[0049] The second step is to determine whether the phase difference is greater than a preset angle (preferably 5°). If it is not greater than the preset angle, execute the third step. If it is greater than the preset angle, execute the fourth step.

[0050] The third step is to determine whether the phase current leads the voltage (for example, if the phase difference between the current and the voltage is positive, the phase current leads the voltage; if the phase difference between the current and the voltage is negative, the phase voltage leads the current). If not, execute the fifth step; if yes, execute the sixth step.

[0051] The fourth step is to determine whether the phase current leads the voltage. If so, proceed to step 7; if not, proceed to step 8.

[0052] The fifth step, that is, when the phase difference is not greater than the preset angle, if the phase current does not lead the voltage, the current frequency f=f-1.

[0053] The sixth step, that is, when the phase difference is not greater than the preset angle, if the phase current leads the voltage, the current frequency f=f+1.

[0054] Step 7, that is, when the phase difference is greater than the preset angle, if the phase current leads the voltage, the current frequency f=(f+f _max ) / 2.

[0055] Step 8, that is, when the phase difference is greater than the preset angle, if the phase current does not lead the voltage, the current frequency f=(f+f _min ) / 2.

[0056] Step nine, enter a new cycle.

[0057] The present invention also provides a rapid tracking device for the resonant frequency of an ultrasonic transducer (hereinafter referred to as a rapid tracking device). The rapid tracking device can track the resonant frequency of the ultrasonic transducer to ensure the stability of the output power and frequency of the ultrasonic wave, and can also improve the tracking speed and accuracy.

[0058] The present invention also provides an ultrasonic drive system, which includes an ultrasonic transducer and the above-mentioned fast tracking device. The ultrasonic transducer can be connected to the fast tracking device for communication, and the fast tracking device can track the resonant frequency of the ultrasonic transducer, thereby controlling the output power and frequency of the ultrasonic wave of the ultrasonic transducer.

[0059] In some embodiments, the fast tracking device 10 may include a sampling module 13, a first processor 11, and a second processor 12. The sampling module 13 may be configured to sample a voltage signal and a current signal of the ultrasonic transducer 20.

[0060] In some embodiments, the first processor 11 may include a first preprocessing module 110. The first preprocessing module 110 may be configured to preprocess the voltage signal and the current signal and output a preprocessed signal.

[0061] In some embodiments, the second processor 12 may include a calculation module 120. The calculation module 120 may be configured to calculate a first amplitude of the voltage signal, a second amplitude of the current signal, and a phase difference between the voltage signal and the current signal based on the preprocessed signal. The calculation module 120 may control the ultrasonic output of the ultrasonic transducer based on the first amplitude, the second amplitude, and the phase difference.

[0062] In the first aspect of the present invention, the tracking of the resonant frequency can be completed by the cooperation of the first processor 11 and the second processor 12. This data processing method can obtain the complete ultrasonic output signal of the ultrasonic transducer in a short time, thereby speeding up the tracking speed of the resonant frequency. Compared with the prior art, the data processing method of the present invention is more efficient and can complete the tracking of the resonant frequency in a shorter time, thereby meeting the needs of high-performance equipment; in addition, the signal processing method of the present invention of first preprocessing and then further calculating can effectively reduce noise interference and improve the tracking accuracy of the ultrasonic output signal of the ultrasonic transducer. Compared with the method of detecting through a rectifier filtering circuit or a zero-crossing circuit in the prior art, the sampling method of the present invention is more accurate and can better eliminate noise interference, thereby improving the accuracy of the resonant frequency.

[0063] In some embodiments, the first processor 11 may be an FPGA. The second processor 12 may be a DSP. The sampling module 13 may be an ADC, which is used to sample the analog signal output by the ultrasonic transducer 20 and convert it into a digital signal that can be recognized by the first processor 10. The present invention uses FPGA+DSP+high-speed AD to sample the ultrasonic output signal of the ultrasonic transducer, and the sampling rate can be greater than 10 times the frequency of the ultrasonic output signal. This method can effectively reduce the delay caused by the rectification and filtering circuit on the circuit and the interference of other frequency noises, and improve the accuracy of the resonant frequency.

[0064] In some embodiments, the second processor 12 may include a second preprocessing module 121. In some embodiments, the preprocessing signal may be non-full-cycle data about a voltage signal and a current signal. The second preprocessing module 121 may be configured to process the non-full-cycle data into full-cycle data. The calculation module 120 may be configured to calculate the first amplitude, the second amplitude, and the phase difference based on the full-cycle data. In this case, the non-full-cycle data of the ultrasonic output signal is collected by the first processor 11, and then the non-full-cycle data is directly completed by the second processor 12, and then the second processor 12 calculates the first amplitude, the second amplitude, and the phase difference. This data processing method can obtain the complete cycle information of the ultrasonic output signal in a short time, thereby speeding up the tracking speed of the resonant frequency. Compared with the prior art, this data processing method of the present invention is more efficient and can complete the tracking of the resonant frequency in a shorter time, thereby meeting the needs of high-performance equipment.

[0065] In some embodiments, the fast tracking device may further include a memory 14. The memory 14 may be a shared memory of the first processor 11 and the second processor 12. In some embodiments, the memory 14 may be a RAM, a ROM, a FLASH, and the like.

[0066] In some embodiments, after collecting the non-full cycle data, the first preprocessing module 110 in the first processor 11 can write the non-full cycle data into the memory 14. The second preprocessing module 121 of the second processor 12 can read the non-full cycle data in the memory 14 and process the non-full cycle data into full cycle data.

[0067] In some embodiments, the signals processed by the first processor 11 and the second processor 12 may be sine wave signals or cosine wave signals. Full-cycle data may be a complete sine wave or cosine wave, and correspondingly, a non-full-cycle signal may be an incomplete sine wave or cosine wave.

[0068] In some embodiments, the non-full-period signal may be half a sine wave or a cosine wave, a quarter of a sine wave or a cosine wave, etc. It is understandable that due to the regularity of the sine wave or the cosine wave, the second pre-processing module 121 can conveniently supplement the non-full-period signal of the sine wave or the cosine wave into a full-period signal.

[0069] In some embodiments, the calculation module 120 may include a first calculation module 120a and a second calculation module 120b. The first calculation module 120a may be configured to calculate a first output value based on the first amplitude and the second amplitude, and control the amplifier to control the ultrasonic output of the ultrasonic transducer 20 based on the first output value. Here, the ultrasonic output of the ultrasonic transducer 20 may be the output power of the ultrasonic output signal of the ultrasonic transducer 20.

[0070] In some embodiments, the amplifier may include a DAC multiplier 16 and a power amplifier circuit 17 .

[0071] In some embodiments, the second calculation module 120b can be configured to calculate a second output value based on the phase difference, and output the second output value to the first processor 11. The first processor 11 can control the ultrasonic output of the ultrasonic transducer based on the second output value. Here, the ultrasonic output of the ultrasonic transducer 20 can be the output frequency of the ultrasonic output signal of the ultrasonic transducer 20.

[0072] In some embodiments, the second processor 12 may also be configured to determine an initial frequency (or calibration frequency) of the voltage signal and the current signal. The second processor 12 may transmit the initial frequency to the first processor 11, and the first processor 11 may control the sampling module 13 to perform high-speed sampling based on the initial frequency.

[0073] In some embodiments, the fast tracking device 10 further includes a waveform generator 111 and a converter 15. The first processor 11 can convert the waveform generated signal through the waveform generator 111 through the converter 15 and output it to the ultrasonic transducer.

[0074] In some embodiments, the waveform generator 111 may be a DDS (Direct Digital Synthesis) or may be integrated into the first processor 11 .

[0075] In some embodiments, the converter 14 may be a DAC for converting a digital signal into an analog signal for output to the ultrasonic transducer 20 .

[0076] In some embodiments, the calculation module 120 may perform FFT (Fast Fourier Transform) calculation to obtain a first amplitude of the voltage signal, a second amplitude of the current signal, and a phase difference between the voltage signal and the current signal.

[0077] In some embodiments, the fast tracking device 10 may further include a DAC multiplier 16. The DAC multiplier 16 may control the ultrasonic output of the ultrasonic transducer 20 based on the first output value.

[0078] In some embodiments, the fast tracking device 10 may further include a power amplifier circuit 17. One end of the power amplifier circuit 17 may be connected to the DAC multiplier 16, and the other end may be connected to the ultrasonic transducer 20. The power amplifier circuit 17 may amplify the control signal and output it to the ultrasonic transducer 20.

[0079] In some embodiments, the first calculation module 120a can perform PID (Proportional-Integral-Derivative Controller) calculation based on the first amplitude and the second amplitude to obtain a first output value. The first output value can be the output value of the DAC multiplier 16 in the next cycle. In this case, the present invention performs PID calculation through DSP, determines the value of the DAC multiplier in the next cycle, and controls it by DSP to achieve constant ultrasonic output. This control method can accurately adjust the ultrasonic output power to keep it stable. Compared with the prior art, the control method of the present invention is more accurate and can effectively improve the stability of the ultrasonic output power.

[0080] In some embodiments, the second calculation module 120b can calculate the second output value based on the phase difference through a binary search and a frequency fine-tuning algorithm. The second output value can be the output frequency of the next cycle. In this case, the present invention tracks the resonant frequency of the transducer by combining a binary search and a frequency fine-tuning method. When the phase difference of the current and voltage signals is greater than a preset angle, the frequency of the next cycle is determined by a binary search based on whether the phase difference is ahead or behind. When the phase difference of the current and voltage is less than a preset angle, the ultrasonic frequency of the next cycle is fine-tuned (for example, plus 1 or minus 1) based on whether the phase difference is ahead or behind. This algorithm combines the advantages of a binary search and a frequency fine-tuning algorithm, and can accurately track the resonant frequency of the transducer under different circumstances. Compared with the prior art, the algorithm of the present invention is more optimized and can adapt to more complex working conditions, thereby improving the tracking accuracy and speed of the resonant frequency.

[0081] In summary, compared with the prior art, the present invention has significant advantages in tracking accuracy, tracking speed, algorithm optimization and output power stability, and can meet the needs of high-performance equipment such as wire bonding machines.

[0082] According to the present invention, a fast tracking device, method and ultrasonic driving system for the resonant frequency of an ultrasonic transducer which can improve the tracking speed and accuracy can be provided.

[0083] The technical solution of the present invention can be widely used in the fields of ultrasonic welding equipment, high-precision measuring instruments, industrial automation control, etc. In the field of ultrasonic welding equipment, the technical solution can realize the rapid adjustment of ultrasonic output frequency and power, thereby improving the accuracy and efficiency of welding. In particular, in high-performance wire bonding machines, the technical solution can meet the high requirements for ultrasonic generator tracking speed and accuracy, thereby improving the quality and stability of welding. In the field of high-precision measuring instruments, the technical solution can realize high-precision sampling and analysis of ultrasonic signals, thereby improving the accuracy and accuracy of measurement. For example, in applications such as ultrasonic ranging and ultrasonic flaw detection, the technical solution can provide more accurate measurement results. In the field of industrial automation control, the technical solution can realize real-time monitoring and control of ultrasonic signals, thereby improving the level of industrial automation. For example, in an automated production line, the technical solution can realize real-time monitoring of ultrasonic sensor signals, thereby improving the operating efficiency and safety of the production line. In general, the technical solution has broad application prospects in the fields of signal processing systems, ultrasonic technology, and programmable logic device design, and can meet the market demand for high-precision, high-efficiency, and high-stability ultrasonic equipment.

[0084] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents, and these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for quickly tracking the resonant frequency of an ultrasonic transducer, which is a method for quickly tracking the resonant frequency of an ultrasonic transducer according to a fast tracking device, characterized in that: include: Sampling the voltage signal and the current signal of the ultrasonic transducer; Preprocessing the voltage signal and the current signal and outputting a preprocessed signal; A first amplitude of the voltage signal, a second amplitude of the current signal, and a phase difference between the voltage signal and the current signal are calculated based on the preprocessed signal, and an ultrasonic output of an ultrasonic transducer is controlled based on the first amplitude, the second amplitude, and the phase difference.

2. The method for quickly tracking the resonant frequency of an ultrasonic transducer according to claim 1, characterized in that: The preprocessed signal is non-full-cycle data about the voltage signal and the current signal. The non-full-cycle data is processed into full-cycle data, and the first amplitude, the second amplitude, and the phase difference are calculated based on the full-cycle data.

3. The method for quickly tracking the resonant frequency of an ultrasonic transducer according to claim 2, characterized in that: After the non-full-cycle data is collected, the non-full-cycle data is written into a memory; the non-full-cycle data in the memory is read and the non-full-cycle data is processed into the full-cycle data.

4. The method for quickly tracking the resonant frequency of an ultrasonic transducer according to claim 3, characterized in that: The full-cycle data is a complete sine wave or cosine wave, and the non-full-cycle data is an incomplete sine wave or cosine wave.

5. The method for fast tracking the resonant frequency of an ultrasonic transducer according to claim 1, characterized in that: calculating a first output value based on the first amplitude and the second amplitude, and controlling an ultrasonic output of the ultrasonic transducer based on the first output value; A second output value is calculated based on the phase difference, and an ultrasonic output of the ultrasonic transducer is controlled based on the second output value.

6. The method for fast tracking the resonant frequency of an ultrasonic transducer according to claim 1, characterized in that: The initial frequencies of the voltage signal and the current signal are determined, and the voltage signal and the current signal are sampled at a high speed based on the initial frequencies.

7. The method for fast tracking the resonant frequency of an ultrasonic transducer according to claim 5, characterized in that: An FFT calculation is performed to obtain the first amplitude of the voltage signal, the second amplitude of the current signal, and the phase difference between the voltage signal and the current signal.

8. The method for fast tracking the resonant frequency of an ultrasonic transducer according to claim 7, characterized in that: A PID calculation is performed based on the first amplitude and the second amplitude to obtain the first output value.

9. The method for fast tracking the resonant frequency of an ultrasonic transducer according to claim 7, characterized in that: The second output value is calculated based on the phase difference by a binary division method and a frequency fine adjustment algorithm.

10. The method for fast tracking the resonant frequency of an ultrasonic transducer according to claim 9, characterized in that: The method for calculating the second output value by using the binary method and the frequency fine-tuning algorithm may include the following steps: The first step is to determine whether the flag bit of the FFT calculation result is refreshed. If not, return to re-judge. If refreshed, execute the second step; The second step is to determine whether the phase difference is greater than a preset angle. If it is not greater than the preset angle, the third step is executed. If it is greater than the preset angle, the fourth step is executed. The third step is to determine whether the phase current leads the voltage. If not, proceed to step 5; if yes, proceed to step 6. The fourth step is to determine whether the phase current leads the voltage. If so, execute the seventh step; if not, execute the eighth step. Step 5, that is, when the phase difference is not greater than the preset angle, if the phase current does not lead the voltage, the current frequency f=f-1; Step 6, that is, when the phase difference is not greater than the preset angle, if the phase current leads the voltage, the current frequency f=f+1; Step 7, that is, when the phase difference is greater than the preset angle, if the phase current leads the voltage, the current frequency f=(f+f _max ) / 2; Step 8, that is, when the phase difference is greater than the preset angle, if the phase current does not lead the voltage, the current frequency f=(f+f _min ) / 2.

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