CN112803779A - Starting method of variable duty ratio LLC resonant converter - Google Patents

Starting method of variable duty ratio LLC resonant converter Download PDF

Info

Publication number
CN112803779A
CN112803779A CN202110133892.2A CN202110133892A CN112803779A CN 112803779 A CN112803779 A CN 112803779A CN 202110133892 A CN202110133892 A CN 202110133892A CN 112803779 A CN112803779 A CN 112803779A
Authority
CN
China
Prior art keywords
control signal
resonant converter
llc resonant
duty ratio
frequency
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202110133892.2A
Other languages
Chinese (zh)
Inventor
王小立
张爽
田蓓
薛飞
李宏强
马鑫
徐恒山
张迪
王超
周雷
任勇
杨慧彪
顾雨嘉
李峰
张汉花
吴玫蓉
梁剑
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
China Three Gorges University CTGU
Electric Power Research Institute of State Grid Ningxia Electric Power Co Ltd
Original Assignee
China Three Gorges University CTGU
Electric Power Research Institute of State Grid Ningxia Electric Power Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by China Three Gorges University CTGU, Electric Power Research Institute of State Grid Ningxia Electric Power Co Ltd filed Critical China Three Gorges University CTGU
Priority to CN202110133892.2A priority Critical patent/CN112803779A/en
Publication of CN112803779A publication Critical patent/CN112803779A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M3/00—Conversion of dc power input into dc power output
    • H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
    • H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
    • H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
    • H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
    • H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
    • H02M3/33569—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/36—Means for starting or stopping converters
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
    • Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Dc-Dc Converters (AREA)

Abstract

The invention provides a starting method of a variable duty ratio LLC resonant converter, and belongs to the technical field of power electronics. The method comprises the following steps: in thattSetting the switching frequency of the LLC resonant converter to be a rated working frequency at the moment of =0, and keeping the switching frequency unchanged in the whole starting process; in thattSetting the duty ratio of a control signal of the LLC resonant converter to 0 at the moment of =0, and gradually increasing the duty ratio of the control signal along with the lapse of time until the duty ratio of the control signal is increased to 50%; when the duty cycle of the control signal increases to 50%, the output voltage of the LLC resonant converterU o And when the voltage value is equal to the rated voltage value of the LLC resonant converter, the LLC resonant converter enters a rated working state.

Description

Starting method of variable duty ratio LLC resonant converter
Technical Field
The invention relates to the technical field of power electronics, in particular to a starting method of a variable duty ratio LLC resonant converter.
Background
The LLC resonant converter is usually controlled by Pulse Frequency Modulation (PFM) technique, and the LLC resonant converter is through changing operating Frequency, and then changes input impedance, so as to achieve the purpose of controlling output voltage, but in the starting process of the LLC resonant converter, if the variable Frequency starting is adopted, two problems will result: if the starting frequency is too low, the input impedance is too large, so that the starting current generates great impact, and the safety operation of a hardware part of the LLC resonant converter is threatened; secondly, a higher switching frequency can be set at the starting moment, and the switching frequency is gradually reduced along with the lapse of the starting time, so that the purpose of reducing the starting impact current is achieved, but the hardware cost of the LLC resonant converter can be improved by using the high starting switching frequency and needing to improve the configuration parameters of the driving chip, and in addition, the method is difficult to realize under the condition of overhigh rated working frequency.
Disclosure of Invention
In view of this, the invention provides a starting method of a variable duty ratio LLC resonant converter, which can achieve smooth starting of the LLC resonant converter, and at the same time, achieve the purposes of reducing starting impact current of the LLC resonant converter and reducing cost of driving hardware.
The technical scheme adopted by the embodiment of the invention for solving the technical problem is as follows:
a starting method of a variable duty ratio LLC resonant converter comprises a primary side high-frequency switching device Q1Primary side high frequency switch device Q2Primary side high frequency switch device Q3And primary side high frequency switching device Q4Resonant capacitorC r Resonant inductorL r High-frequency isolation transformer T and secondary high-frequency rectifier diode D1Secondary high-frequency rectifier diode D2Secondary high-frequency rectifier diode D3Secondary high-frequency rectifier diode D4Voltage stabilizing capacitorC o And a load resistorR o ，
Said Q1And said Q2Are connected in parallel and are all connected to an input main current power supplyU in The positive electrode of (1), the Q1And said Q3In series, said Q2And said Q4In series, said Q3And said Q4After being connected in parallel and are all connected toU in Negative pole of said transformer TOne end of the side winding is connected in series withL r Is connected to the Q1And said Q3The other end of the primary winding of the transformer T is connected in series with the node a betweenC r Is connected to the Q2And said Q4A primary winding of the transformer T is connected with an excitation inductor in parallel at two endsL m ，
One end of the secondary winding of the transformer T is connected to the secondary winding D1And the anode of (D)3The other end of the secondary winding of the transformer T is connected to the secondary winding of the transformer D2And the anode of (D)4A cathode of (2), saidC o Is connected to said D3And the anode of (D)4Of said anode, saidC o Is connected to said D at the other end1And the cathode and the anode2A cathode of (2), saidR o And the above-mentionedC o In parallel, theR o The voltage at two ends is the output voltage of the LLC resonant converterU o ，
The starting method comprises the following steps:
in thattSetting the switching frequency of the LLC resonant converter to be a rated working frequency at the moment of =0, and keeping the switching frequency unchanged in the whole starting process;
in thattSetting the duty ratio of a control signal of the LLC resonant converter to 0 at the moment of =0, and gradually increasing the duty ratio of the control signal along with the lapse of time until the duty ratio of the control signal is increased to 50%;
when the duty cycle of the control signal increases to 50%, the output voltage of the LLC resonant converterU o And when the voltage value is equal to the rated voltage value of the LLC resonant converter, the LLC resonant converter enters a rated working state.
Preferably, the control signals 1Is said Q1Control signal of (2), control signals 2Is said Q2Control signal of (2), control signals 3Is said Q3Control signal ofSignal making devices 4Is said Q4The control signal of (2).
Preferably, the control signals 1And the control signals 4In phase, the control signals 2And the control signals 3In phase, the control signals 1The control signals 2The control signals 3And said control signals 4Of equal frequency, said control signals 1The control signals 2The control signals 3And said control signals 4Is 50%, the control signals 1The control signals 2The control signals 3And said control signals 4Is 0.
Preferably, when the duty ratio of the control signal is 0, the output voltageU o Is 0V; when the duty ratio of the control signal is increased to 50%, the output voltageU o Is the rated voltage value.
Preferably, the duty cycle of the control signal is increased from 0 to 50% linearly, and the output voltage is increasedU o Increasing from 0V to the rated voltage value, the output voltageU o The waveform of (2) has no overshoot phenomenon.
According to the technical scheme, the starting method of the variable duty ratio LLC resonant converter provided by the embodiment of the invention has the advantages that at the starting moment, the frequency of the switching device of the LLC resonant converter is set to be the rated working frequency, the control signal of the switching device is set to be 0, the switching frequency of the LLC resonant converter is kept unchanged along with the time, and the duty ratio of the switching device is gradually increased to 50% under the condition of neglecting the dead time of the control signal of the switching device, so that the smooth starting of the LLC resonant converter is realized, the starting impact current of the LLC resonant converter can be reduced, the cost of driving hardware is reduced, and the stability of the output voltage in the starting process is improved.
Drawings
Fig. 1 is a circuit configuration diagram of an LLC resonant converter according to an embodiment of the present invention.
Fig. 2 is a flowchart of a starting method of a variable duty ratio LLC resonant converter in an embodiment of the present invention.
Fig. 3 is a duty ratio schematic diagram of a starting method of a variable duty ratio LLC resonant converter in the embodiment of the present invention.
Fig. 4 is a diagram of simulation results of the duty ratio, the output voltage and the resonant current obtained by the starting method of the variable duty ratio LLC resonant converter in the embodiment of the present invention.
In the figure: primary side high frequency switch device Q1Primary side high frequency switch device Q2Primary side high frequency switch device Q3And primary side high frequency switching device Q4Resonant capacitorC r Resonant inductorL r High-frequency isolation transformer T and secondary high-frequency rectifier diode D1Secondary high-frequency rectifier diode D2Secondary high-frequency rectifier diode D3Secondary high-frequency rectifier diode D4Voltage stabilizing capacitorC o Load resistorR o Inputting main current powerU in Output voltage of the power supplyU o Resonant currenti r Exciting current of transformeri m Excitation inductor of transformerL m Control signals 1Control signals 2Control signals 3Control signals 4Node a, node b.
Detailed Description
Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar elements and variables refer to the same or similar elements and variables throughout the description. This example is only one application specific of the invention and should not be construed as limiting the invention.
The embodiment provides a starting method of a variable duty ratio LLC resonant converter, and the implementation main body is the LLC resonant converter shown in fig. 1The resonant converter is suitable for a full-bridge LLC resonant converter and a half-bridge LLC resonant converter, and specifically comprises a primary side high-frequency switching device Q1Primary side high frequency switch device Q2Primary side high frequency switch device Q3And primary side high frequency switching device Q4Resonant capacitorC r Resonant inductorL r High-frequency isolation transformer T and secondary high-frequency rectifier diode D1Secondary high-frequency rectifier diode D2Secondary high-frequency rectifier diode D3Secondary high-frequency rectifier diode D4Voltage stabilizing capacitorC o And a load resistorR o 。
Wherein Q is1And Q2Are connected in parallel and are all connected to an input main current power supplyU in Positive electrode of (2), Q1And Q3In series, Q2And Q4In series, Q3And Q4Are connected in parallel and are all connected toU in One end of the primary winding of the transformer T is connected in seriesL r Is connected to Q1And Q3The other end of the primary winding of the transformer T is connected in series with the node a betweenC r Is connected to Q2And Q4A node b between, two ends of the primary winding of the transformer T are connected with an excitation inductor in parallelL m One end of the secondary winding of the transformer T is connected to D1And D3The other end of the secondary winding of the transformer T is connected to D2And D4The cathode of (a) is provided,C o is connected at one end to D3And D4The anode of (a) is provided,C o is connected at the other end to D1And D2The cathode of (a) is provided,R o andC o the two are connected in parallel,R o the voltage at two ends is the output voltage of LLC resonant converterU o . Signals 1Is Q1Control signal, signals 2Is Q2Control signal, signals 3Is Q3Control signal, signals 4Is Q4The control signal of (2).
As shown in fig. 2, for the problem that the LLC resonant converter has an excessively high starting frequency or an excessively large starting inrush current in the starting process, the starting method of the variable duty ratio LLC resonant converter provided by the embodiment of the present invention includes the following steps:
step S1, attSetting the switching frequency of the LLC resonant converter to be a rated working frequency at the moment of =0, and keeping the switching frequency unchanged in the whole starting process;
step S2, attSetting the duty ratio of a control signal of the LLC resonant converter to 0 at the moment of =0, and gradually increasing the duty ratio of the control signal along with the lapse of time until the duty ratio of the control signal is increased to 50%;
step S3, when the duty ratio of the control signal is increased to 50%, the output voltage of the LLC resonant converterU o And the voltage is equal to the rated voltage value of the LLC resonant converter, and the LLC resonant converter enters a rated working state.
Wherein the control signals 1And control signals 4In phase, control signals 2And control signals 3In phase, control signals 1Control signals 2Control signals 3And a control signals 4Are equal in signal frequency, control signals 1Control signals 2Control signals 3And a control signals 4Is 50%, and the control signals 1Control signals 2Control signals 3And a control signals 4Is 0.
Primary side high frequency switch device Q1、Q2、Q3And Q4As shown in fig. 3, step S1 istControl signals of all switches in LLC resonant converter at time point of =0s 1Control signals 2Control signals 3And a control signals 4Are all set to 0, and the respective controls are gradually increased as time goes byThe duty ratio of the signal is increased until the duty ratio is increased to 50%, the whole increasing process is linear increasing, and the upper limit of the duty ratio is also 50%.
Duty cycle at LLC resonant converterdDuring the gradual increase from 0 to 50%, the resonant current as shown in FIG. 4i r Wave form, resonant currenti r Will gradually increase, but the resonant current will increase during the whole start-up processi r Does not exceed the peak value of the rated state of the LLC resonant converter, which indicates that the resonant current is in the starting processi r The impact and the damage to a hardware circuit of the LLC resonant converter can not be caused.
When the duty ratio of the control signal is increased to 50%, the output voltageU o Is a rated voltage value. Duty cycle at LLC resonant converterdDuring the gradual increase from 0 to 50%, the output voltage is as shown in FIG. 4U o Waveform of (2), output voltageU o Gradually increasing from 0V to 400V of rated output voltage value after starting, and outputting voltage in the process of increasingU o And the overshoot phenomenon is avoided, so that the stability of the output voltage is good in the starting process.
In the technical scheme of the invention, the switching frequency of the LLC resonant converter in the whole starting process is constant, the starting frequency is equal to the rated working frequency, the reduction of the impact current is not required to be obtained by pushing high frequency at the starting moment, the hardware cost of a driving circuit is favorably reduced, and the driving loss of the LLC resonant converter at the starting moment can be reduced; the LLC resonant converter has lower switching frequency in the starting process, namely lower driving frequency, so that the drive loss is reduced, and the service life of a drive chip is prolonged; duty ratio of LLC resonant converter control signaldThe starting impact current is small when the voltage is gradually increased from 0 to 50 percent, and the output voltage has no overshoot problem, thereby being beneficial to improving the stability of the system.
According to the technical scheme, the starting method of the variable duty ratio LLC resonant converter provided by the embodiment of the invention has the advantages that at the starting moment, the frequency of the switching device of the LLC resonant converter is set to be the rated working frequency, the control signal of the switching device is set to be 0, the switching frequency of the LLC resonant converter is kept unchanged along with the time, and the duty ratio of the switching device is gradually increased to 50% under the condition of neglecting the dead time of the control signal of the switching device, so that the smooth starting of the LLC resonant converter is realized, the starting impact current of the LLC resonant converter can be reduced, the cost of driving hardware is reduced, and the stability of the output voltage in the starting process is improved.
While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention.

Claims (5)

1. A starting method of a variable duty ratio LLC resonant converter is characterized in that,
the LLC resonant converter comprises a primary side high-frequency switching device Q1Primary side high frequency switch device Q2Primary side high frequency switch device Q3And primary side high frequency switching device Q4Resonant capacitorC r Resonant inductorL r High-frequency isolation transformer T and secondary high-frequency rectifier diode D1Secondary high-frequency rectifier diode D2Secondary high-frequency rectifier diode D3Secondary high-frequency rectifier diode D4Voltage stabilizing capacitorC o And a load resistorR o ，
Said Q1And said Q2Are connected in parallel and are all connected to an input main current power supplyU in The positive electrode of (1), the Q1And said Q3In series, said Q2And said Q4In series, said Q3And said Q4After being connected in parallel and are all connected toU in One end of the primary winding of the transformer T is connected in series with the negative electrode of (1)L r Is connected to the Q1And said Q3The other end of the primary winding of the transformer T is connected in series with the node a betweenC r Is connected to the Q2And said Q4A primary winding of the transformer T is connected with an excitation inductor in parallel at two endsL m ，
One end of the secondary winding of the transformer T is connected to the secondary winding D1And the anode of (D)3The other end of the secondary winding of the transformer T is connected to the secondary winding of the transformer D2And the anode of (D)4A cathode of (2), saidC o Is connected to said D3And the anode of (D)4Of said anode, saidC o Is connected to said D at the other end1And the cathode and the anode2A cathode of (2), saidR o And the above-mentionedC o In parallel, theR o The voltage at two ends is the output voltage of the LLC resonant converterU o ，
The starting method comprises the following steps:
in thattSetting the switching frequency of the LLC resonant converter to be a rated working frequency at the moment of =0, and keeping the switching frequency unchanged in the whole starting process;
in thattSetting the duty ratio of a control signal of the LLC resonant converter to 0 at the moment of =0, and gradually increasing the duty ratio of the control signal along with the lapse of time until the duty ratio of the control signal is increased to 50%;
when the duty cycle of the control signal increases to 50%, the output voltage of the LLC resonant converterU o And when the voltage value is equal to the rated voltage value of the LLC resonant converter, the LLC resonant converter enters a rated working state.
2. The method of starting a variable duty ratio LLC resonant converter as claimed in claim 1, wherein the control signals 1Is said Q1Control signal of (2), control signals 2Is said Q2Control signal of (2), control signals 3Is said Q3Control signal of (2), control signals 4Is said Q4Control signal ofNumber (n).
3. The method of starting a variable duty ratio LLC resonant converter as claimed in claim 2, wherein said control signals 1And the control signals 4In phase, the control signals 2And the control signals 3In phase, the control signals 1The control signals 2The control signals 3And said control signals 4Of equal frequency, said control signals 1The control signals 2The control signals 3And said control signals 4Is 50%, the control signals 1The control signals 2The control signals 3And said control signals 4Is 0.
4. The method of starting a variable duty ratio LLC resonant converter as claimed in claim 1, wherein when the duty ratio of said control signal is 0, said output voltage isU o Is 0V; when the duty ratio of the control signal is increased to 50%, the output voltageU o Is the rated voltage value.
5. The method of claim 1, wherein the duty cycle of the control signal is increased linearly from 0 to 50% and the output voltage is increased linearlyU o Increasing from 0V to the rated voltage value, the output voltageU o The waveform of (2) has no overshoot phenomenon.
CN202110133892.2A 2021-02-01 2021-02-01 Starting method of variable duty ratio LLC resonant converter Pending CN112803779A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110133892.2A CN112803779A (en) 2021-02-01 2021-02-01 Starting method of variable duty ratio LLC resonant converter

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110133892.2A CN112803779A (en) 2021-02-01 2021-02-01 Starting method of variable duty ratio LLC resonant converter

Publications (1)

Publication Number Publication Date
CN112803779A true CN112803779A (en) 2021-05-14

Family

ID=75813242

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110133892.2A Pending CN112803779A (en) 2021-02-01 2021-02-01 Starting method of variable duty ratio LLC resonant converter

Country Status (1)

Country Link
CN (1) CN112803779A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113783410A (en) * 2021-09-16 2021-12-10 浙江吉利控股集团有限公司 Starting control method of phase-shifted full-bridge converter and phase-shifted full-bridge converter
CN114679043A (en) * 2022-05-26 2022-06-28 深圳市首航新能源股份有限公司 Voltage spike suppression method, control unit and resonant converter

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103812321A (en) * 2014-03-13 2014-05-21 南京航空航天大学 Starting control method for input-series output-quasi-parallel multiplexed output converter
CN105099157A (en) * 2015-08-12 2015-11-25 阳光电源股份有限公司 LLC resonant converter and soft starting method thereof
CN109004816A (en) * 2018-07-04 2018-12-14 华南理工大学 A kind of two-way LLC resonant converter low current stress soft start control method
CN112003477A (en) * 2020-08-10 2020-11-27 中电普瑞电力工程有限公司 Direct-current transformer and soft start control method thereof

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103812321A (en) * 2014-03-13 2014-05-21 南京航空航天大学 Starting control method for input-series output-quasi-parallel multiplexed output converter
CN105099157A (en) * 2015-08-12 2015-11-25 阳光电源股份有限公司 LLC resonant converter and soft starting method thereof
CN109004816A (en) * 2018-07-04 2018-12-14 华南理工大学 A kind of two-way LLC resonant converter low current stress soft start control method
CN112003477A (en) * 2020-08-10 2020-11-27 中电普瑞电力工程有限公司 Direct-current transformer and soft start control method thereof

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113783410A (en) * 2021-09-16 2021-12-10 浙江吉利控股集团有限公司 Starting control method of phase-shifted full-bridge converter and phase-shifted full-bridge converter
CN113783410B (en) * 2021-09-16 2024-03-01 浙江吉利控股集团有限公司 Starting control method of phase-shifting full-bridge converter and phase-shifting full-bridge converter
CN114679043A (en) * 2022-05-26 2022-06-28 深圳市首航新能源股份有限公司 Voltage spike suppression method, control unit and resonant converter

Similar Documents

Publication Publication Date Title
CN111130353B (en) Switching power supply device
US8441812B2 (en) Series resonant converter having a circuit configuration that prevents leading current
CN210518900U (en) High-power microwave power supply with adjustable duty ratio
CN102281047A (en) LLC (resonance inductor, magnetizing inductor and resonance capacitor) series resonance combined controller
CN112803779A (en) Starting method of variable duty ratio LLC resonant converter
CN110719035B (en) Topological structure of single-stage DAB-LLC hybrid bidirectional DC-DC converter
CN111030462B (en) Active clamp flyback converter and control method
CN113659820B (en) Soft start control method of LLC resonant converter
TW453134B (en) Resonant converter circuit
CN110165895B (en) Circuit structure and control method for realizing wide-gain FB-HB LLC resonant converter
CN109245545B (en) High-voltage gain LCL resonant DC-DC converter
CN109194142B (en) LLC full-bridge converter soft start control method based on hybrid control
CN112564489B (en) Mode control method of switch converter and switch converter
CN111224555B (en) Wide-range output control method of LLC resonant conversion circuit
CN112838766A (en) High-voltage-reduction-ratio three-level LLC resonant converter and control method thereof
CN111525809A (en) High-frequency hybrid direct-current converter with adjustable output voltage
CN109713904B (en) Flyback power conversion circuit and conversion control circuit and control method thereof
CN111030468B (en) Control method and control circuit of clamping switch power supply
US9960689B1 (en) Resonant control device and resonant control method thereof
CN101242144B (en) Method for controlling DC-DC converter
CN113452260A (en) Hybrid LLC resonant converter topological structure based on working mode switching and control method
JP2003259643A (en) Current resonance type soft switching power circuit
CN115864813A (en) Soft start device and method for CLLC resonant converter
CN209982343U (en) Circuit structure for realizing wide-gain FB-HB LLC resonant converter
CN114710012A (en) Control method and control circuit of switching power supply and switching power supply

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
RJ01 Rejection of invention patent application after publication

Application publication date: 20210514

RJ01 Rejection of invention patent application after publication