A high-frequency ultrasonic power supply and control method thereof, and high-frequency ultrasonic equipment

Abstract

The present invention relates to the field of ultrasonic power supply technology, and in particular to a high-frequency ultrasonic power supply, a control method thereof, and a high-frequency ultrasonic device. A sampling circuit measures the actual output voltage and current and calculates the actual power of the load; a power controller generates a voltage control instruction based on the difference between a set power threshold and the actual power of the load, and limits it through a power limiter; a voltage controller generates a current control instruction based on the difference between the voltage control instruction output by the voltage controller limiter and the actual output voltage, and limits it through a voltage limiter. A current controller generates a drive control signal based on the difference between the current control instruction output by the current controller limiter and the actual output current, and limits it through a duty cycle limiter; the drive control signal output by the duty cycle limiter adjusts the duty cycle of the switching tube of the DC / DC converter, thereby adjusting the actual power, current, and voltage of the load. The present invention enables the power supply to always meet the control requirements of voltage, current, and power.

Description

Technical Field

[0001] The present invention relates to the technical field of ultrasonic power supplies, and in particular to a high-frequency ultrasonic power supply and a control method thereof, as well as high-frequency ultrasonic equipment. Background Art

[0002] Ultrasonic technology was first used in the late 19th and early 20th centuries. After decades of development and research, its application has become increasingly widespread. Power ultrasonic equipment primarily consists of an ultrasonic transducer and an ultrasonic power supply. The ultrasonic power supply is constructed from power electronic circuits. An AC / DC converter converts industrial-frequency alternating current (AC) to direct current (DC), which is then inverted back to high-frequency AC by a DC / AC converter. The transducer receives the high-frequency AC power and converts it into high-frequency mechanical vibrations, generating ultrasonic waves. In recent years, advancements in ultrasonic power supply technology have significantly expanded the scope of their applications. The output frequency of ultrasonic power supplies has gradually increased, covering a range of 20kHz to 10MHz. This increase in output frequency means a higher switching frequency for ultrasonic power supply components, greater ultrasonic energy concentration, and deeper penetration, resulting in improved ultrasonic processing or inspection results. Furthermore, advancements in control algorithms have significantly improved the response speed and control accuracy of ultrasonic power supplies, enabling them to meet increasingly complex and sophisticated control requirements. Ultrasonic power supplies are widely used in both medical and industrial fields. In the medical field, ultrasonic technology is used in ultrasonic imaging, ultrasonic scalpels, ultrasonic ablation and other equipment to assist doctors in diagnosis and treatment; in the industrial field, ultrasonic technology is used in cleaning, welding, cutting, grinding and other processes, significantly improving production efficiency and product quality.

[0003] Based on current power electronics technology, ultrasonic power supplies primarily consist of power electronics circuits constructed with fully controlled semiconductor power devices (MOSFETs and IGBTs). Ultrasonic transducers typically serve as the load at the output of ultrasonic power supplies, and their output impedance often varies widely with load changes. Failure to promptly adjust the output voltage and power when the load changes dynamically can easily lead to overcurrent and overload in the output circuit and load. In severe cases, this can cause damage to the ultrasonic power supply's power components and the load. To adjust power based on changes in load impedance, existing ultrasonic power supplies generally employ a sampling circuit at the power supply output to monitor the load voltage and current in real time. Based on this voltage and current data, the system can calculate the load impedance and power. Using open-loop or closed-loop control strategies, the system adjusts the duty cycle of the DC / AC converter, ultimately controlling the ultrasonic power supply's output power. In this control strategy, closed-loop control primarily relies on feedback regulation based on output power. When the load impedance fluctuates significantly, the system adjusts the duty cycle to maintain output power stability.

[0004] However, the existing control methods need to detect the instantaneous values ​​of the output voltage and current in order to accurately measure the impedance. Conventional sampling circuits include: sampling resistors and op amp conditioning circuits, Hall sensors, current transformers, etc. However, these sampling circuits are limited by the bandwidth of the components and can generally meet the sampling of output signals of tens of kilohertz and below. When the output frequency of the ultrasonic power supply is increased to hundreds of kHz or even several MHz, the signal distortion and phase lag caused by the conventional voltage and current detection methods have a large impact, making it difficult to achieve the required control accuracy. The real-time detection methods of high-frequency (MHz level) voltage and current, such as magnetic ring method, current probe, power meter, etc., have greater insulation difficulties, and the volume and cost are also greatly increased accordingly, and some methods are not sufficiently integrable. In addition, this method of closed-loop control based only on output power may cause the output current or voltage to exceed the safety threshold when the load impedance changes over a large range. Considering the resistive load R, according to When the load resistance is low, the current easily exceeds the threshold; when the load resistance is high, the voltage easily exceeds the threshold. These voltage and current overshoots can easily damage the ultrasonic transducer load and the power components of the power supply. However, simply limiting the output voltage and current can lead to insufficient output power control accuracy, limiting the output power and failing to meet the power supply's output requirements. Summary of the Invention

[0005] To this end, the technical problem to be solved by the present invention is to overcome the defects of the existing control method that the cost of detecting the instantaneous values ​​of the output voltage and current is too high, and when the load impedance changes over a large range, the output current or voltage may exceed the safety threshold, thereby damaging the ultrasonic transducer load and power supply power devices.

[0006] To solve the above technical problems, the present invention provides a high-frequency ultrasonic power supply, comprising:

[0007] Power circuit, including:

[0008] An AC / DC converter, the input of which is connected to an AC power source, and the output of which is connected to a DC / AC converter;

[0009] A DC / AC converter, an input end of which is connected to the AC / DC converter, and an output end of which is connected to the load;

[0010] Control loop, including:

[0011] The sampling circuit has an input end connected to the load and an output end connected to the power controller, the voltage controller, and the current controller; the sampling circuit measures the actual output voltage and the actual output current of the load and calculates the actual power of the load;

[0012] After receiving the actual power of the load output by the sampling circuit, the power controller generates a voltage control instruction based on the difference between the set power threshold and the actual power of the load;

[0013] A voltage controller limiter, whose input end is connected to the power controller to limit the voltage control instruction, and whose output end is connected to the voltage controller;

[0014] After receiving the voltage control instruction output by the voltage controller limiter, the voltage controller generates a current control instruction based on the difference between the voltage control instruction and the actual output voltage of the load;

[0015] A current controller limiter, whose input end is connected to the voltage controller to limit the current control instruction, and whose output end is connected to the current controller;

[0016] After receiving the current control instruction output by the current controller limiter, the current controller generates a drive control signal based on the difference between the current control instruction and the actual output current of the load;

[0017] The duty cycle limiter has its input connected to the current controller to limit the drive control signal, and its output is used to output the drive control signal to the DC / AC converter. By adjusting the duty cycle of the DC / AC converter's switching tube, the voltage output by the DC / AC converter is adjusted, thereby controlling the actual power, actual output current, and actual output voltage of the load.

[0018] Preferably, the power circuit further includes:

[0019] The DC / DC converter has an input end connected to the output end of the AC / DC converter, and an output end connected to the input end of the DC / AC converter.

[0020] Preferably, the duty cycle limiter has its input end connected to the current controller to limit the drive control signal, and its output end is used to output the drive control signal to the DC / DC converter. By adjusting the duty cycle of the switching tube of the DC / DC converter, the voltage output by the DC / DC converter is adjusted, and the actual power, current and voltage of the load are controlled through the DC / AC converter.

[0021] Preferably, limiting the voltage control instruction by a voltage control limiter includes:

[0022] When the voltage control instruction is greater than the maximum threshold value in the preset voltage range, the voltage control instruction is set to the maximum threshold value in the preset voltage range;

[0023] When the voltage control command is within the preset voltage range, the voltage control command remains unchanged.

[0024] Preferably, limiting the current control instruction by a current control limiter includes:

[0025] When the current control instruction is greater than the maximum threshold value in the preset current range, the current control instruction is set to the maximum threshold value in the preset current range;

[0026] When the current control command is within the preset current range, the current control command remains unchanged.

[0027] Preferably, limiting the driving control signal by a duty cycle limiter includes:

[0028] When the driving control signal is greater than the maximum threshold value in the preset duty cycle range, setting the driving control signal to the maximum threshold value in the preset duty cycle range;

[0029] When the driving control signal is within the preset duty cycle range, the driving control signal remains unchanged.

[0030] Preferably, the preset duty cycle range is [0, 0.5].

[0031] The present invention also provides a method for controlling a high-frequency ultrasonic power supply, comprising:

[0032] The actual output voltage and actual output current of the load are measured by a sampling circuit connected to the load, and the actual power of the load is calculated;

[0033] Calculate the difference between the set power threshold and the actual power of the load. The power controller generates a voltage control instruction based on the difference between the set power threshold and the actual power of the load, and limits the voltage control instruction through the voltage control limiter.

[0034] Calculate the difference between the voltage control command output by the voltage control limiter and the actual output voltage. The voltage controller generates a current control command based on the difference between the voltage control command output by the voltage control limiter and the actual output voltage of the load, and limits the current control command through the current control limiter.

[0035] Calculating the difference between the current control command output by the current control limiter and the actual output current of the load; the current controller generates a drive control signal based on the difference between the current control command output by the current control limiter and the actual output current of the load, and limits the drive control signal through the duty cycle limiter;

[0036] According to the driving control signal output by the duty cycle limiter, the duty cycle of the switching tube of the DC / AC converter is adjusted to adjust the output voltage of the DC / AC converter, thereby controlling the actual power, actual output current and actual output voltage of the load.

[0037] The present invention also provides a high-frequency ultrasonic device, comprising:

[0038] A high-frequency ultrasonic power supply as described above;

[0039] The ultrasonic transducer has an input end connected to the output end of the DC / AC converter, and an output end connected to the input end of the control loop.

[0040] The above technical solution of the present invention has the following beneficial effects compared with the prior art:

[0041] The high-frequency ultrasonic power supply, control method thereof, and high-frequency ultrasonic equipment described in the present invention do not require a high-frequency detection and conditioning circuit to detect the instantaneous values ​​of the output voltage and output current in real time. The actual output voltage and actual output current of the load are measured by a sampling circuit connected to the load, and the actual power of the load is calculated. By measuring the effective values ​​of the output voltage and output current of the load, the cost of the detection circuit and related components is effectively reduced. The power controller generates a voltage control instruction based on the difference between the set power threshold and the actual power of the load, and limits the voltage control instruction through the voltage control limiter; the voltage controller generates a current control instruction based on the difference between the voltage control instruction output by the voltage control limiter and the actual output voltage of the load, and limits the current control instruction through the current control limiter; the current controller generates a drive control signal based on the difference between the current control instruction output by the current control limiter and the actual output current of the load, and limits the drive control signal through the duty cycle limiter; according to the drive control signal output by the duty cycle limiter, the duty cycle of the switching tube of the DC / AC converter is adjusted to adjust the voltage output by the DC / AC converter, thereby controlling the actual power, actual output current and actual output voltage of the load. Simply limiting the output voltage and current can easily lead to limited output power. The three-closed-loop control proposed in the present invention can dynamically enter the corresponding closed-loop control mode when the load impedance changes according to the set voltage, current and power ranges, ensuring that the power supply always maintains maximum output in the safe working area within the full range of load impedance, and switching between control modes is smooth and without transition process, thereby improving the output response speed and accuracy of the high-frequency ultrasonic power supply.

[0042] In addition, the present invention also introduces a DC / DC converter, wherein the input end of the DC / DC converter is connected to the output end of the AC / DC converter, and the output end of the DC / DC converter is connected to the input end of the DC / AC converter. The duty cycle limiter outputs a driving control signal to the DC / DC converter, and by adjusting the duty cycle of the switching tube of the DC / DC converter, the voltage output by the DC / DC converter is adjusted, and the actual power, current and voltage of the load are controlled by the DC / AC converter. Directly adjusting the duty cycle of the switching tube of the DC / AC converter may cause the calculation frequency of the controller and the switching frequency of the power device to be too high. Especially at high frequencies, the output of the DC / AC converter is unstable, which will cause large power loss. The DC / DC converter controls the output voltage by adjusting the duty cycle, which can accurately control energy transmission with low loss. It can not only improve the efficiency and stability of the power supply, but also simplify the control strategy and reduce the power loss of the ultrasonic power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments of the present invention in conjunction with the accompanying drawings, wherein:

[0044] Figure 1 It is a structural diagram of a high-frequency ultrasonic power supply.

[0045] Figure 2 It is a schematic diagram of voltage, current and power curves.

[0046] Figure 3 The following are the simulated waveforms of the output voltage and output current when the load is 10Ω.

[0047] Figure 4 The following are the simulated waveforms of the output voltage and output current when the load is 15Ω.

[0048] Figure 5 This is the simulated waveform of the effective value of the output current when the load is 15Ω.

[0049] Figure 6 The following are the simulated waveforms of the output voltage and output current when the load is 80Ω.

[0050] Figure 7 This is the simulated waveform of the effective value of the output current when the load is 100Ω. DETAILED DESCRIPTION

[0051] The present invention will be further described below with reference to the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it. However, the embodiments are not intended to limit the present invention.

[0052] like Figure 1 As stated, Figure 1 This is a structural diagram of a high-frequency ultrasonic power supply.

[0053] Embodiment 1 of the present invention provides a high-frequency ultrasonic power supply, including:

[0054] Power circuit, including:

[0055] An AC / DC converter, the input of which is connected to an AC power source, and the output of which is connected to a DC / AC converter;

[0056] A DC / AC converter, an input end of which is connected to the AC / DC converter, and an output end of which is connected to the load;

[0057] Control loop, including:

[0058] The sampling circuit has an input end connected to the load and an output end connected to the power controller, the voltage controller, and the current controller; the sampling circuit measures the actual output voltage and the actual output current of the load and calculates the actual power of the load;

[0059] After receiving the actual power of the load output by the sampling circuit, the power controller generates a voltage control instruction based on the difference between the set power threshold and the actual power of the load;

[0060] A voltage controller limiter, whose input end is connected to the power controller to limit the voltage control instruction, and whose output end is connected to the voltage controller;

[0061] In this embodiment, preferably, limiting the voltage control instruction by a voltage control limiter includes:

[0062] When the voltage control instruction is greater than the maximum threshold value in the preset voltage range, the voltage control instruction is set to the maximum threshold value in the preset voltage range;

[0063] When the voltage control command is within the preset voltage range, the voltage control command remains unchanged.

[0064] After receiving the voltage control instruction output by the voltage controller limiter, the voltage controller generates a current control instruction based on the difference between the voltage control instruction and the actual output voltage of the load;

[0065] A current controller limiter, whose input end is connected to the voltage controller to limit the current control instruction, and whose output end is connected to the current controller;

[0066] In this embodiment, preferably, limiting the current control instruction by a current control limiter includes:

[0067] When the current control instruction is greater than the maximum threshold value in the preset current range, the current control instruction is set to the maximum threshold value in the preset current range;

[0068] When the current control command is within the preset current range, the current control command remains unchanged.

[0069] After receiving the current control instruction output by the current controller limiter, the current controller generates a drive control signal based on the difference between the current control instruction and the actual output current of the load;

[0070] The duty cycle limiter has its input connected to the current controller to limit the drive control signal, and its output is used to output the drive control signal to the DC / AC converter. By adjusting the duty cycle of the DC / AC converter's switching tube, the voltage output by the DC / AC converter is adjusted, thereby controlling the actual power, actual output current, and actual output voltage of the load.

[0071] In this embodiment, preferably, limiting the driving control signal by a duty cycle limiter includes:

[0072] When the driving control signal is greater than the maximum threshold value in the preset duty cycle range, setting the driving control signal to the maximum threshold value in the preset duty cycle range;

[0073] When the driving control signal is within the preset duty cycle range, the driving control signal remains unchanged.

[0074] In this embodiment, specifically, the preset duty cycle range is [0, 0.5].

[0075] In this embodiment, preferably, the power circuit further includes:

[0076] The DC / DC converter has an input end connected to the output end of the AC / DC converter, and an output end connected to the input end of the DC / AC converter.

[0077] In this embodiment, preferably, the duty cycle limiter has its input end connected to the current controller to limit the drive control signal, and its output end is used to output the drive control signal to the DC / DC converter, and by adjusting the duty cycle of the switching tube of the DC / DC converter to adjust the voltage output by the DC / DC converter, the actual power, current and voltage of the load are controlled through the DC / AC converter.

[0078] The present invention introduces a DC / DC converter, wherein the input end of the DC / DC converter is connected to the output end of the AC / DC converter, and the output end of the DC / DC converter is connected to the input end of the DC / AC converter. A duty cycle limiter outputs a driving control signal to the DC / DC converter, and by adjusting the duty cycle of the switching tube of the DC / DC converter, the voltage output by the DC / DC converter is adjusted, and the actual power, current, and voltage of the load are controlled by the DC / AC converter. Directly adjusting the duty cycle of the switching tube of the DC / AC converter may cause the output of the DC / AC converter to be unstable, resulting in large power loss, especially at high frequencies. However, the DC / DC converter controls the output voltage by adjusting the duty cycle, which can accurately control energy transmission with low loss. This not only improves the efficiency and stability of the power supply, but also simplifies the control strategy and reduces the power loss of the ultrasonic power supply.

[0079] A second embodiment of the present invention provides a method for controlling a high-frequency ultrasonic power supply, including:

[0080] The actual output voltage and actual output current of the load are measured by a sampling circuit connected to the load, and the actual power of the load is calculated;

[0081] Calculate the difference between the set power threshold and the actual power of the load. The power controller generates a voltage control instruction based on the difference between the set power threshold and the actual power of the load, and limits the voltage control instruction through the voltage control limiter.

[0082] Calculate the difference between the voltage control command output by the voltage control limiter and the actual output voltage. The voltage controller generates a current control command based on the difference between the voltage control command output by the voltage control limiter and the actual output voltage of the load, and limits the current control command through the current control limiter.

[0083] Calculating the difference between the current control command output by the current control limiter and the actual output current of the load; the current controller generates a drive control signal based on the difference between the current control command output by the current control limiter and the actual output current of the load, and limits the drive control signal through the duty cycle limiter;

[0084] According to the driving control signal output by the duty cycle limiter, the duty cycle of the switching tube of the DC / AC converter is adjusted to adjust the output voltage of the DC / AC converter, thereby controlling the actual power, actual output current and actual output voltage of the load.

[0085] like Figure 2 As shown, Figure 2Figure 2 is a schematic diagram of the voltage, current, and power curves. This invention divides the varying load impedance into three distinct zones based on the corresponding safe operating region: the constant current zone, the constant power zone, and the constant voltage zone. This control algorithm ensures that the ultrasonic power supply consistently meets the voltage, current, and power control requirements during operation, even when the load impedance varies widely. This control algorithm has been validated in simulations and experimental platforms.

[0086] When the load impedance is greater than 0 and less than or equal to R1, as the load impedance increases, the current closed loop is entered, and the controller controls the actual output current of the load to be the set current threshold. At this time, the current controller is in an unsaturated state, and the voltage controller and power controller are in a saturated state; wherein, To set the power threshold, is the maximum threshold in the preset current range.

[0087] When the load impedance is greater than R1 and less than or equal to R2, as the load impedance increases, the power closed loop is entered, and the actual power of the load controlled by the controller is the set power threshold. At this time, the power controller is in an unsaturated state, and the current controller and voltage controller are in a saturated state; wherein, To set the power threshold, is the maximum threshold in the preset current range, is the maximum threshold in the preset voltage range.

[0088] When the load impedance is greater than R2, as the load impedance increases, the voltage closed loop is entered, and the actual output voltage of the controller controls the load to be the set voltage threshold. At this time, the voltage controller is in an unsaturated state, and the current controller and power controller are in a saturated state; wherein, To set the power threshold, is the maximum threshold in the preset voltage range.

[0089] As shown in Table 1, Table 1 shows the load impedance and its corresponding closed-loop state.

[0090] Table 1

[0091]

[0092] The three-closed-loop control proposed in the present invention can dynamically enter the corresponding closed-loop control mode when the load impedance changes according to the set voltage, current and power ranges, ensuring that the power supply always maintains maximum output in the safe working area within the full range of load impedance, and switching between control modes is smooth and without transition process, thereby improving the output response speed and accuracy of the high-frequency ultrasonic power supply.

[0093] The third embodiment of the present invention simulates a high-frequency ultrasonic power supply proposed in the first embodiment, as shown in Table 2. Table 2 is a list of simulation and experimental parameters provided in the third embodiment.

[0094] Table 2

[0095]

[0096] Where U is the actual output voltage of the load, and f is the output frequency of the DC / AC converter.

[0097] like Figure 3 As shown, Figure 3 The simulated waveforms of the output voltage and output current when the load is 10Ω are as follows: Figure 4 As shown, Figure 4 The simulated waveforms of the output voltage and output current when the load is 15Ω are shown in Figure 2. Figure 3 、 4 It can be seen that the output voltage and output current are relatively stable when the load is 10Ω and 15Ω. Figure 5 The simulated waveform of the effective value of the output current when the load is 15Ω is 3A after reaching stability. When the load is 15Ω, the effective value of the output voltage is 45V and the output power is 135W, which meets the requirements of the output curve. Figure 6 As shown, Figure 6 The following are the simulated waveforms of the output voltage and output current when the load is 80Ω. 80Ω is the turning point from the constant power region to the constant voltage region. The power is still stable at 135W. At this time, the system enters the voltage closed loop and the voltage gradually stabilizes. When the load impedance increases to 80Ω, although the system enters the voltage closed loop, the power is still maintained at 135W, which satisfies the smooth transition from the constant power region to the constant voltage region and ensures the continuity and stability of energy. Figure 7 As shown, Figure 7 The following are the simulated waveforms of the output voltage and output current when the load is 100Ω. After simulation measurement, the output voltage is basically stable at 104V and the current is also 1.039A, which fully verifies the stability and control accuracy of the system in the constant voltage area.

[0098] The above simulations fully demonstrate that under different load conditions, the voltage and current of the present invention can remain relatively stable, thus avoiding the voltage and current instability caused by load fluctuations.

[0099] A fourth embodiment of the present invention provides a high-frequency ultrasonic device, including:

[0100] A high-frequency ultrasonic power supply as described above;

[0101] The ultrasonic transducer has an input end connected to the output end of the DC / AC converter, and an output end connected to the input end of the control loop.

[0102] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0103] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0104] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0105] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0106] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A high-frequency ultrasonic power supply, characterized in that: include: Power circuit, including: An AC / DC converter, the input of which is connected to an AC power source, and the output of which is connected to a DC / AC converter; A DC / AC converter, an input end of which is connected to the AC / DC converter, and an output end of which is connected to the load; Control loop, including: The sampling circuit has an input end connected to the load and an output end connected to the power controller, the voltage controller, and the current controller; the sampling circuit measures the actual output voltage and the actual output current of the load and calculates the actual power of the load; After receiving the actual power of the load output by the sampling circuit, the power controller generates a voltage control instruction based on the difference between the set power threshold and the actual power of the load; A voltage controller limiter, whose input end is connected to the power controller to limit the voltage control instruction, and whose output end is connected to the voltage controller; After receiving the voltage control instruction output by the voltage controller limiter, the voltage controller generates a current control instruction based on the difference between the voltage control instruction and the actual output voltage of the load; A current controller limiter, whose input end is connected to the voltage controller to limit the current control instruction, and whose output end is connected to the current controller; After receiving the current control instruction output by the current controller limiter, the current controller generates a drive control signal based on the difference between the current control instruction and the actual output current of the load; The duty cycle limiter has its input connected to the current controller to limit the drive control signal, and its output is used to output the drive control signal to the DC / AC converter. By adjusting the duty cycle of the DC / AC converter's switching tube, the voltage output by the DC / AC converter is adjusted, thereby controlling the actual power, actual output current, and actual output voltage of the load.

2. A high-frequency ultrasonic power supply according to claim 1, characterized in that: The power circuit also includes: The DC / DC converter has an input end connected to the output end of the AC / DC converter, and an output end connected to the input end of the DC / AC converter.

3. A high-frequency ultrasonic power supply according to claim 2, characterized in that: The duty cycle limiter has its input connected to the current controller to limit the drive control signal, and its output is used to output the drive control signal to the DC / DC converter. By adjusting the duty cycle of the DC / DC converter's switching tube, the voltage output by the DC / DC converter is adjusted, and the actual power, current and voltage of the load are controlled through the DC / AC converter.

4. A high-frequency ultrasonic power supply according to claim 1, characterized in that: The voltage control command is limited by the voltage control limiter, including: When the voltage control instruction is greater than the maximum threshold value in the preset voltage range, the voltage control instruction is set to the maximum threshold value in the preset voltage range; When the voltage control command is within the preset voltage range, the voltage control command remains unchanged.

5. A high-frequency ultrasonic power supply according to claim 1, characterized in that: The current control command is limited by the current control limiter, including: When the current control instruction is greater than the maximum threshold value in the preset current range, the current control instruction is set to the maximum threshold value in the preset current range; When the current control command is within the preset current range, the current control command remains unchanged.

6. A high-frequency ultrasonic power supply according to claim 1, characterized in that: The duty cycle limiter is used to limit the drive control signal, including: When the driving control signal is greater than the maximum threshold value in the preset duty cycle range, setting the driving control signal to the maximum threshold value in the preset duty cycle range; When the driving control signal is within the preset duty cycle range, the driving control signal remains unchanged.

7. A high-frequency ultrasonic power supply according to claim 6, characterized in that: The preset duty cycle range is [0, 0.5].

8. A method for controlling a high-frequency ultrasonic power supply according to any one of claims 1 to 7, characterized in that: include: The actual output voltage and actual output current of the load are measured by a sampling circuit connected to the load, and the actual power of the load is calculated; Calculate the difference between the set power threshold and the actual power of the load. The power controller generates a voltage control instruction based on the difference between the set power threshold and the actual power of the load, and limits the voltage control instruction through the voltage control limiter. Calculate the difference between the voltage control command output by the voltage control limiter and the actual output voltage. The voltage controller generates a current control command based on the difference between the voltage control command output by the voltage control limiter and the actual output voltage of the load, and limits the current control command through the current control limiter. Calculating the difference between the current control command output by the current control limiter and the actual output current of the load; the current controller generates a drive control signal based on the difference between the current control command output by the current control limiter and the actual output current of the load, and limits the drive control signal through the duty cycle limiter; According to the driving control signal output by the duty cycle limiter, the duty cycle of the switching tube of the DC / AC converter is adjusted to adjust the output voltage of the DC / AC converter, thereby controlling the actual power, actual output current and actual output voltage of the load.

9. A high-frequency ultrasonic device, characterized in that: include: A high-frequency ultrasonic power supply according to any one of claims 1 to 7; The ultrasonic transducer has an input end connected to the output end of the DC / AC converter, and an output end connected to the input end of the control loop.

Images