A current source type high-frequency driving circuit and driving method

Abstract

This application relates to the field of power electronic circuit technology and discloses a current-source type high-frequency drive circuit and driving method, which corresponds to the current-source type high-frequency drive circuit. This application achieves rapid switching of power switching transistors to reduce switching losses, while simultaneously recovering gate energy dissipated in traditional drivers to reduce drive losses; the boost function reduces the on-resistance of the power switching transistors and reduces conductivity losses; the bipolar gate voltage reduces the phenomenon of false turn-on of the switching transistors caused by crosstalk; under high-frequency, low-power conditions, the negative drive voltage eliminates the current transfer phenomenon present in traditional current-type drives to a certain extent; under high-frequency, high-power conditions, the bidirectional switch completely eliminates current transfer, further improving drive capability and achieving high-current rapid drive; the calculation of the duty cycle suppresses the overshoot of the drive voltage during the dead time, ensuring stable drive operation.

Description

Technical Field

[0001] This application relates to the field of power electronic circuit technology, specifically a current source type high-frequency drive circuit and driving method. Background Technology

[0002] Voltage-driven (VSD) controls the switching speed of the switching transistor by applying a constant voltage and changing the external gate resistor. During the driving process, the drive current decreases exponentially over time. Current-driven (CSD) applies a constant drive current, resulting in lower drive losses.

[0003] Constant current drives can be mainly divided into inductive and non-inductive types. Non-inductive drives are based on the working principle of current mirrors. Due to the large number of switching devices, they are currently less commonly used. Inductive constant current drives have been the subject of much research, but none of them can simultaneously meet the requirements of constant drive current, negative voltage turn-off, and fewer switching devices. Moreover, most (over 90%) of them currently suffer from current transfer problems. Summary of the Invention

[0004] The purpose of this application is to provide a current source type high-frequency drive circuit and driving method to solve the technical problems in the prior art that make it difficult to respond to the requirements of constant drive current, adjustable positive and negative drive voltage, fewer switching devices and no current transfer.

[0005] To achieve the above objectives, this application provides a current-source type high-frequency drive circuit, including a resonant capacitor, a coupling inductor, a first switching transistor, a second switching transistor, and a power switching transistor; wherein: the power switching transistor is provided with a corresponding power switching transistor gate-source capacitor; the coupling inductor includes a first inductor and a second inductor; the first switching transistor and the second switching transistor are unidirectional switches;

[0006] The connection relationship of the current source type high-frequency drive circuit includes at least the following: the drain of the first switching transistor and one end of the second inductor are both connected to the positive terminal of the drive power supply; the source of the first switching transistor is connected to one end of the resonant capacitor; the other end of the second inductor, the same-name terminal of the first inductor, and one end of the gate-source capacitor of the power switching transistor are all connected to the gate of the power switching transistor; the drain of the second switching transistor and the other end of the first inductor are both connected to the other end of the resonant capacitor; and the source of the second switching transistor, the other end of the gate-source capacitor of the power switching transistor, and the source of the power switching transistor are all connected to the negative terminal of the drive power supply.

[0007] Preferably, the first and second switching transistors are replaced with bidirectional switches.

[0008] Preferably, in a current-source type high-frequency drive circuit, the mathematical expression for the turns ratio between the first inductor and the second inductor constituting the coupling inductor and the conditions that the drive voltage must satisfy is as follows:

[0009]

[0010]

[0011] in: The turns ratio between the first inductor and the second inductor that form the coupled inductor; To drive positive pressure; To drive negative pressure; This is the driving power supply voltage.

[0012] Preferably, in a current-source type high-frequency drive circuit, the mathematical expression for the condition that the sum of the first inductance and the second inductance constituting the coupling inductor must satisfy is:

[0013]

[0014] in: The first inductor; For the second inductor Drive current during dead time The value; Duty cycle; This is the driving cycle.

[0015] Preferably, in a current-source type high-frequency drive circuit, the minimum value of the resonant capacitor must satisfy the following mathematical expression:

[0016]

[0017] in: This represents the minimum value corresponding to the calculated resonant capacitance.

[0018] Preferably, the value of the resonant capacitor is 2 to 3 times the minimum value of the calculated resonant capacitor.

[0019] Preferably, the current source type high-frequency drive circuit is equipped with a corresponding driving method, which includes:

[0020] Step 1: Provide drive signals to the first and second switching transistors, and wait for the drive voltages of the first and second switching transistors to stabilize;

[0021] Step 2: Slowly increase the drive power supply voltage to the preset value;

[0022] Step 3: Use the duty cycle control circuit to adjust the duty cycle so that the peak value of the drive voltage is adjusted to a suitable value.

[0023] Preferably, in the driving method, the duty cycle control circuit calculates the duty cycle based on the duty cycle calculation formula when adjusting the duty cycle. The duty cycle calculation formula is:

[0024]

[0025] in: The duty cycle is calculated; The turns ratio between the first inductor and the second inductor that form the coupled inductor; This is the driving power supply voltage; For driving cycle; For the gate-source capacitance of the power switch transistor; To drive positive pressure Drive negative pressure.

[0026] Preferably, in step two, the preset value in the step of slowly increasing the drive power supply voltage to the preset value is the drive power supply voltage. .

[0027] Preferably, the drive power supply is configured to have a soft-start function or to have a large capacitor connected in parallel to the drive power supply output.

[0028] Beneficial effects: The current-source type high-frequency drive circuit and driving method of this application realize rapid switching of power switching transistors to reduce switching losses, and at the same time can recover the gate energy dissipated in traditional drivers to reduce drive losses; the boost function reduces the on-resistance of power switching transistors and reduces conduction losses; the bipolar gate voltage reduces the phenomenon of false turn-on of switching transistors caused by crosstalk; under high-frequency low-power conditions, the negative drive voltage eliminates the current transfer phenomenon existing in traditional current-type drives to a certain extent; under high-frequency high-power conditions, the bidirectional switch completely eliminates current transfer, further improving the driving capability and realizing high-current rapid drive; the calculation of duty cycle suppresses the overshoot of drive voltage in the dead time, ensuring stable drive operation. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 The circuit schematic diagram of the current source type high-frequency drive circuit under unidirectional switching provided in the embodiments of this application;

[0031] Figure 2 The circuit schematic diagram of the current source type high-frequency drive circuit under bidirectional switching provided in the embodiments of this application;

[0032] Figure 3 The current source type high-frequency drive circuit provided in the embodiments of this application is in the time period The working mode;

[0033] Figure 4The current source type high-frequency drive circuit provided in the embodiments of this application is in the time period The working mode;

[0034] Figure 5 The current source type high-frequency drive circuit provided in the embodiments of this application is in the time period Work mode one;

[0035] Figure 6 The current source type high-frequency drive circuit provided in the embodiments of this application is in the time period Working mode two;

[0036] Figure 7 The current source type high-frequency drive circuit provided in the embodiments of this application is in the time period The working mode;

[0037] Figure 8 The current source type high-frequency drive circuit provided in the embodiments of this application is in the time period The working mode;

[0038] Figure 9 The coupling inductor current corresponding to the current source type high-frequency driving circuit and driving method provided in the embodiments of this application ( , ), drive current and driving voltage Waveform diagram of the switch action.

[0039] The implementation, functional features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0040] The technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0041] In this document, the term "comprising" is intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0042] The current source type high-frequency driving circuit and driving method disclosed in this embodiment will now be briefly described.

[0043] This embodiment of the current-source high-frequency drive circuit and method achieves constant current drive with few switches and controllable positive and negative voltages. Simultaneously, under high-frequency, high-power conditions, addressing the common current transfer problem in current-source drives, the current transfer path is optimized by replacing the original high-speed single-switch transistor with two sets of bidirectional switches, achieving zero current transfer and thus obtaining high-current drive. To suppress overshoot of the drive voltage during the dead time, the duty cycle needs to be calculated and dynamically adjusted according to the current circuit voltage overshoot. Duty cycle control includes a peak detection circuit and a proportional-integral (PI) circuit. The peak detection circuit acquires the peak value of the drive voltage in real time for each cycle. Since the peak drive voltage is approximately inversely proportional to the duty cycle, the PI circuit adjusts the duty cycle in real time based on the current peak drive voltage, suppressing voltage overshoot caused by duty cycle deviation and parasitic parameters, ensuring stable drive operation.

[0044] The current source type high-frequency drive circuit disclosed in this embodiment will now be described in detail.

[0045] The current-source type high-frequency drive circuit in this embodiment includes a resonant capacitor. Coupled inductor, first switching transistor Second switching transistor and power switching transistors; wherein: the power switching transistors are equipped with corresponding power switching transistor gate-source capacitors. resonant capacitor Used to change the direction of inductor current; the coupled inductor includes a first inductor. Second Inductor The coupling inductor is used to store energy to provide constant current drive and drive voltage clamping; the first switching transistor... Second switching transistor The first switching transistor is a high-speed, low-stress switching transistor. Second switching transistor The corresponding opening times are complementary and a certain dead zone time is allowed.

[0046] Reference Figure 1 , Figure 1 The circuit diagram of the current source type high-frequency drive circuit provided in the embodiment of this application under unidirectional switching.

[0047] like Figure 1 As shown, the first switching transistor The drain and the second inductor One end of each transistor is connected to the positive terminal of the drive power supply. The source and resonant capacitor One end is connected to the second inductor. The other end, the first inductor The same terminal and the gate-source capacitor of the power switch One end of each is connected to the gate of the power switch transistor, and the second switch transistor... The drain and the first inductor The other end is connected to the resonant capacitor. The other end is connected to the second switch. The source and gate-source capacitance of the power switch The other end and the source of the power switch are both connected to the negative terminal of the drive power supply.

[0048] Reference Figure 2 , Figure 2 The circuit diagram of the current source type high-frequency drive circuit provided in the embodiment of this application under bidirectional switching.

[0049] like Figure 2 As shown, similarly, we obtained the circuit schematic of the current source type high-frequency drive circuit under bidirectional switching in this embodiment.

[0050] Regarding the component parameters in the current source type high-frequency drive circuit of this embodiment, the following design was carried out.

[0051] Due to the driving positive pressure With driving negative pressure The clamping effect is affected by the first inductor that constitutes the coupling inductor. Second Inductor The number of turns ratio between and drive power supply voltage The influence of this. Therefore, the first inductance that constitutes the coupled inductor. Second Inductor The number of turns ratio between and drive power supply voltage Need to be based on the required drive positive pressure With driving negative pressure Strict control was implemented. Therefore, we designed the corresponding first inductor that constitutes the coupled inductor. With the second inductor The number of turns ratio between and drive power supply voltage The mathematical expression that requires the conditions to be met is:

[0052]

[0053]

[0054] Due to the dead-time drive current value The value of the coupling inductance depends on the value of the coupling inductor. Therefore, to ensure fast driving of the power transistor, the value of the coupling inductor needs to be strictly controlled according to the required drive power supply current. The corresponding first inductance that constitutes the coupling inductor... With the second inductor The mathematical expression for the sum and the condition that it must satisfy is:

[0055]

[0056] in: For the driving cycle, This refers to the duty cycle.

[0057] The maximum values ​​of the primary and secondary sides of the coupling inductor can be calculated based on the required drive power supply current, drive positive voltage, and drive negative voltage. Simultaneously, the coupling inductor is tightly wound to make the coupling coefficient close to 1, thereby reducing leakage inductance and thus reducing drive circuit oscillation. For ease of implementation, it is recommended that the actual value of the coupling inductor be between 80% and 90% of the calculated value.

[0058] The above calculation is based on the premise of resonant capacitance. During charging and discharging, the voltage across its terminals is approximately equal to the driving power supply voltage and remains essentially constant, meaning the voltage variation is less than 5%. Therefore, the resonant capacitor... The value is relatively large, and the resonant capacitor Corresponding minimum value The following mathematical expression must be satisfied:

[0059]

[0060] The resonant capacitance can be calculated based on the driving current, driving voltage, and coupling inductance. The minimum value, however, the excessively large resonant capacitance. This will result in a slow charging speed, which slows down the driver startup. Therefore, the actual value should be 2 to 3 times the calculated value.

[0061] The driving method of the current source type high-frequency driving circuit disclosed in this embodiment will now be described in detail.

[0062] The voltage clamping effect of the drive circuit relies on the resonant capacitor. The resonant capacitor of the drive circuit during the startup phase Charging is required, therefore the drive voltage will exceed the threshold of the power switch during startup, and this is also due to the resonant capacitor. Charging is achieved through the first switching transistor. Second switching transistor The current will also increase, damaging the switching transistor. Therefore, we designed a current source type high-frequency drive circuit driving method, including the following steps:

[0063] Step 1: Apply power to the first switching transistor Second switching transistor To ensure the safety of the power switching transistor, the initial duty cycle of the drive signal should be between D and 0.5, waiting for the first switching transistor. Second switching transistor The driving voltage is stable.

[0064] Step 2: Slowly increase the drive power supply voltage to The drive power supply should have a soft-start function or a large capacitor connected in parallel with the drive power supply output to allow the drive power supply voltage to rise slowly.

[0065] Step 3: Use the duty cycle control circuit to adjust the duty cycle appropriately so that the peak value of the drive voltage is adjusted to a suitable value.

[0066] In practical applications, to control the overshoot of the drive voltage during the dead time, the dead time needs to be calculated and strictly controlled. Duty cycle The mathematical expression is:

[0067]

[0068] It should be noted that the duty cycle in this embodiment... The mathematical expression is derived based on the design of the component parameters in the current source type high-frequency drive circuit of this embodiment, and the derivation process will be described in detail in the following description of the working mode.

[0069] Based on the driving method of the current source type high-frequency driving circuit in this embodiment, we specifically describe the operating logic of the current source type high-frequency driving circuit in this embodiment as follows:

[0070] When the first switching transistor Second switching transistor When all are off and the power switching transistors are charged to their rated voltage, the first inductor Second inductor With resonant capacitor First switching transistor The parallel diodes form a discharge circuit, and the first inductor Second Inductor The voltage across the terminals remains constant, and the drive voltage of the power switch is clamped.

[0071] When the first switching transistor Second switching transistor When all switches are off and the power switches are discharged to their rated voltage, the gate capacitance of the power switches... First Inductor Second switching transistor The parallel diodes form a discharge circuit, and the gate capacitance of the power switch is... Second inductor A discharge circuit is formed with the drive power supply, and the drive voltage of the power switch is clamped.

[0072] When the first switching transistor Turn off, second switching transistor When turned on, the first inductor Second inductor The first inductor forms a circuit with the drive power supply. Second Inductor During charging, the current increases evenly.

[0073] When the first switching transistor On, second switching transistor When turned off, the first inductor Second inductor Resonant capacitor With the first switching transistor Forming a circuit, the first inductor Second Inductor The current decreases uniformly to zero and then increases in the opposite direction.

[0074] Reference Figures 3 to 8 , Figure 3 The current-source type high-frequency drive circuit provided in the embodiments of this application, in a single cycle The six working modes within, among which, .

[0075] like Figures 3 to 8 As shown, the current source type high-frequency drive circuit of this embodiment has the following modes:

[0076] like Figure 3 As shown, during the time period At that time, the second switching transistor Turn on and the first switching transistor Turn off, drive power supply voltage Added to the first inductor Second Inductor At both ends, due to the input capacitor of the power switch at this time The voltage across the terminals is the driving positive voltage. Although the second inductor The same-named end will sense positive pressure, and will also because Point voltage Unable to continue Charging, therefore and Linear increase, driving voltage Keep it constant.

[0077] like Figure 4 As shown, during the time period At that time, the first switching transistor Second switching transistor All are off, due to the first inductor There was originally an electric current, and the energy stored in the magnetic field cannot change abruptly. This magnetic field energy passes through the first inductor. Second Inductor Maintain together, and All remain constant. Maintain constant current discharge until driving negative voltage .

[0078] During the period At times, such as Figure 5 As shown, when The voltage at both ends reaches the driving negative voltage hour, , It will pass through the second switching transistor The parallel diodes are discharging; such as Figure 6 As shown, Keep Then the first switching transistor Turn on, second switch tube Turn off, first inductor The current decreases linearly to zero, and then increases linearly in the opposite direction. At this point, we have:

[0079]

[0080]

[0081]

[0082] The negative driving voltage can then be derived:

[0083]

[0084] in: For the driving power supply voltage, To drive negative pressure, For the second inductor With the first inductor The number of turns ratio.

[0085] like Figure 7 As shown, during the time period At that time, the first switching transistor Second switching transistor All are off, due to the first inductor There was originally an electric current, and the energy stored in the magnetic field cannot change abruptly. This magnetic field energy passes through the first inductor. Second Inductor Maintain together, and All remain constant. Maintain a constant current, charging to the drive positive voltage. At this point, we have:

[0086]

[0087]

[0088]

[0089] The positive driving pressure can then be derived:

[0090]

[0091] in: For the driving power supply voltage, To drive positive pressure, For the second inductor With the first inductor The number of turns ratio.

[0092] according to and The first inductance constituting the coupled inductor can then be derived. With the second inductor ratio and drive power supply voltage The mathematical expression that satisfies the conditions is as described above:

[0093]

[0094]

[0095] like Figure 8 As shown, during the time period At that time, the first switching transistor Second switching transistor All are off. The voltage at both ends reaches ,and The voltages at both ends are equal. Stop charging. Keep constant, and The average decreases linearly to zero.

[0096] For high-frequency, high-power circuits, replacing the single switching transistor of the current source driver with two sets of bidirectional switches completely solves the current shunting problem when charging and discharging the power switching transistor. During the dead time of the two switching transistors, the branch that originally achieved voltage clamping through a single switch connected in parallel with a diode no longer exists, so the drive voltage will continuously increase. To control the overshoot of the drive voltage during the dead time, the dead time needs to be calculated and strictly controlled. The magnitude of the drive current during the dead time is affected by the period, duty cycle, and coupling inductance value, with the specific relationships as follows:

[0097]

[0098] in: Drive power supply current during dead time Size, For the duty cycle of the switching transistor, Given the duty cycle, after the switch changes, based on the fact that the energy stored in the coupled inductor remains constant, we have:

[0099]

[0100]

[0101] in: For coupled inductors and mutual inductance, The second inductor after the switch is switched The current value.

[0102] Therefore, based on the input capacitance of the power switch transistor Charging during the dead time yields:

[0103]

[0104] The duty cycle can be derived from the above formula. for:

[0105]

[0106] in: The input capacitor for the power switch transistor. This refers to the duty cycle.

[0107] A small inductor (approximately a few nH, utilizing the parasitic inductance of the circuit) is added to the output of the drive power supply. This inductor resonates with the resonant capacitor during switching, slowing down the rate of change of the resonant capacitor current during the switching process. For high-frequency, high-power applications, a bidirectional switch is used. To suppress overshoot of the drive voltage during the dead time, the duty cycle needs to be calculated and dynamically adjusted based on the current circuit voltage overshoot. Duty cycle control includes a peak detection circuit and a proportional-integral (PI) circuit. The peak detection circuit acquires the peak value of the drive voltage for each cycle in real time. Since the peak drive voltage is approximately inversely proportional to the duty cycle, the PI circuit adjusts the duty cycle in real time based on the current peak drive voltage, suppressing voltage overshoot caused by duty cycle deviation and parasitic parameters, ensuring stable drive operation.

[0108] Reference Figure 9 , Figure 9 The coupling inductor current corresponding to the current source type high-frequency driving circuit and driving method provided in the embodiments of this application ( , ), drive current and driving voltage Waveform diagram of the switch action.

[0109] like Figure 9 As shown, based on the current source type high-frequency drive circuit and drive method of this embodiment, bipolar gate voltage controllable drive is realized. During the dead time of the two switching transistors, the drive presents a constant current drive. All the current of the coupling inductor flows into the gate-source capacitor of the power transistor, and there is no current transfer. The drive voltage can rise or fall rapidly and uniformly.

[0110] In summary, the current-source type high-frequency drive circuit and method of this embodiment achieve rapid switching of power transistors to reduce switching losses, while simultaneously recovering the gate energy dissipated in traditional drivers to reduce drive losses. Because the drive circuit has a boost function, the gate-source voltage of the power transistor can be increased to exceed the drive power supply voltage, thereby reducing the on-resistance of the power transistor and reducing conduction losses. This drive circuit has a bipolar gate voltage, reducing the phenomenon of false turn-on of the switching transistor caused by crosstalk. Under high-frequency, low-power conditions, the drive circuit has a complete voltage clamping effect throughout the entire cycle, and the negative drive voltage eliminates the current transfer phenomenon present in traditional current-type drives to a certain extent. Under high-frequency, high-power conditions, bidirectional switching completely eliminates current transfer, further improving drive capability and achieving rapid high-current drive. To suppress overshoot of the drive voltage during the dead time, the duty cycle needs to be calculated and dynamically adjusted according to the current circuit voltage overshoot. The duty cycle control includes a peak detection circuit and a proportional-integral circuit. The peak detection circuit collects the peak value of the driving voltage in each cycle in real time. Since the peak value of the driving voltage is approximately inversely proportional to the duty cycle, the proportional-integral circuit adjusts the duty cycle in real time according to the current peak value of the driving voltage. This can suppress voltage overshoot caused by duty cycle deviation and parasitic parameters, and ensure stable operation of the drive.

[0111] Finally, it should be noted that the above description is only a preferred embodiment of this application and is not intended to limit this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A current source type high-frequency drive circuit characterized by comprising: It includes a resonant capacitor, a coupling inductor, a first switching transistor, a second switching transistor, and a power switching transistor; wherein: the power switching transistor has a corresponding power switching transistor gate-source capacitor; the coupling inductor includes a first inductor and a second inductor; the first switching transistor and the second switching transistor are unidirectional switches; The connection relationship of the current source type high frequency drive circuit includes at least the following: the drain of the first switching transistor and one end of the second inductor are both connected to the positive terminal of the drive power supply; the source of the first switching transistor is connected to one end of the resonant capacitor; the other end of the second inductor, the same-name terminal of the first inductor, and one end of the gate-source capacitor of the power switching transistor are all connected to the gate of the power switching transistor; the drain of the second switching transistor and the other end of the first inductor are both connected to the other end of the resonant capacitor; and the source of the second switching transistor, the other end of the gate-source capacitor of the power switching transistor, and the source of the power switching transistor are all connected to the negative terminal of the drive power supply. In a current-source type high-frequency drive circuit, the mathematical expressions for the turns ratio between the first and second inductors constituting the coupling inductor and the conditions that the drive voltage must satisfy are as follows: wherein: is a turns ratio between the first inductance and the second inductance constituting the coupled inductance; is a driving positive voltage; is a driving negative voltage; is a driving power voltage; In a current-source type high-frequency drive circuit, the mathematical expression for the condition that the sum of the first inductance and the second inductance constituting the coupling inductor must satisfy is: wherein: is a first inductance is a second inductance is a dead time drive current is a value of the dead time drive current; is a duty cycle; is a drive period.

2. The current source type high-frequency drive circuit according to claim 1, characterized in that, Replace the first and second switching transistors with bidirectional switches.

3. The current source type high-frequency drive circuit according to claim 1, characterized in that, In current-source type high-frequency drive circuits, the minimum value of the resonant capacitor must satisfy the following mathematical expression: in: This represents the minimum value corresponding to the calculated resonant capacitance.

4. The current source type high-frequency drive circuit according to claim 3, characterized in that, The value of the resonant capacitor is 2 to 3 times the minimum value of the calculated resonant capacitor.

5. A driving method for a current-source type high-frequency driving circuit, applicable to the current-source type high-frequency driving circuit as described in any one of claims 1 to 4, characterized in that, The current source type high-frequency drive circuit is equipped with a corresponding driving method, which includes: Step 1: Provide drive signals to the first and second switching transistors, and wait for the drive voltages of the first and second switching transistors to stabilize; Step 2: Slowly increase the drive power supply voltage to the preset value; Step 3: Use the duty cycle control circuit to adjust the duty cycle so that the peak value of the drive voltage is adjusted to a suitable value.

6. The driving method for the current source type high-frequency driving circuit according to claim 5, characterized in that, In the driving method, the duty cycle control circuit adjusts the duty cycle based on the duty cycle calculation formula, which is: in: The duty cycle is calculated; The turns ratio between the first inductor and the second inductor that form the coupled inductor; This is the driving power supply voltage; For driving cycle; For the gate-source capacitance of the power switch transistor; To drive positive pressure Drive negative pressure.

7. The driving method for the current source type high-frequency driving circuit according to claim 6, characterized in that, In step two, the drive power supply voltage is slowly increased to the preset value, which is the drive power supply voltage. .

8. The driving method for the current source type high-frequency driving circuit according to claim 7, characterized in that, The drive power supply is configured to have a soft-start function or to have a large capacitor connected in parallel with the drive power supply output.

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