CN111181408B - Resonant converter based on hybrid rectification structure and control method - Google Patents

Resonant converter based on hybrid rectification structure and control method Download PDF

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Publication number
CN111181408B
CN111181408B CN202010075867.9A CN202010075867A CN111181408B CN 111181408 B CN111181408 B CN 111181408B CN 202010075867 A CN202010075867 A CN 202010075867A CN 111181408 B CN111181408 B CN 111181408B
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secondary side
primary side
switching tube
switch tube
tube
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CN111181408A (en
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潘健
刘松林
陈庆东
吕磊
陈凤娇
刘孙德
张琦
陈光义
刘雨晴
熊嘉鑫
宋豪杰
石迪
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Hubei University of Technology
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    • 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
    • H02M3/33576—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 having at least one active switching element at the secondary side of an isolation transformer
    • 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

Abstract

The invention provides a resonant converter based on a hybrid rectification structure and a control method thereof, wherein the resonant converter consists of a DC converterStream input source (V)in) The primary side half-bridge LLC resonant circuit (10), the transformer (T), the secondary side hybrid rectifying circuit (20) and the output resistor load (R)o) The working mode of the secondary side hybrid rectification circuit (20) can be switched between a full-bridge rectification mode and a voltage-multiplying rectification mode, so that the converter has a plurality of control methods, can adopt frequency conversion control in a narrow frequency range, can also adopt pulse width modulation control in a fixed frequency range, can also adopt pulse width modulation control in a frequency conversion mode, and has flexible control modes. The control method reduces the switching frequency variation range of the primary side switching tube, is beneficial to the design of magnetic components, improves the voltage gain range, efficiency and power density of the converter, and meets the requirement of wide voltage gain range conversion occasions.

Description

Resonant converter based on hybrid rectification structure and control method
Technical Field
The invention relates to a resonant converter with a hybrid rectification circuit structure and a hybrid control method, belonging to the technical field of power electronic converters, in particular to the technical field of an isolated DC-DC converter.
Background
The isolated DC-DC converter is widely applied to engineering practice, and mainly applied to the fields of data centers, server power supplies, vehicle-mounted chargers of electric automobiles, DC micro-grids, fuel cell systems, LED driving circuits and the like. Converters in these applications require a wide voltage gain adjustment range to meet wide input or output voltage requirements. Increasing the voltage gain range, efficiency and power density of such converters has been a sought goal in the art. The LLC resonant converter has a simple structure, and has excellent characteristics of high efficiency, high power density, low electromagnetic interference, current isolation, low cost, and the like, including a zero-voltage switch (ZVS) for the switching tube on the primary side and a zero-current switch (ZCS) for the rectifying diode on the secondary side, and has recently become a research focus of people's attention.
In particular, when the switching frequency is far away from the resonant frequency, magnetic components are difficult to be magnetically integrated, at the moment, a resonant circuit has larger circulating current, and the conduction loss of the switching tube is seriously increased.
In order to increase the voltage gain range of the resonant converter, two methods are commonly used by researchers to improve the conventional resonant converter. The first method adds an auxiliary power switch device and the other method improves the control strategy of the resonant converter. However, both of these approaches increase the complexity and design cost of the control circuit, reducing reliability.
Disclosure of Invention
The invention aims to provide a resonant converter with a hybrid rectification structure and a control method for application occasions with wide voltage gain range aiming at the defects of the prior art.
The invention provides a resonant converter based on a hybrid rectification structure, which is characterized in that a direct current input source V is adoptedinPrimary side half-bridge LLC resonant circuit 10, transformer T, secondary side hybrid rectifying circuit 20 and output resistance load RoThe working mode of the secondary side hybrid rectification circuit 20 can be switched between a full-bridge rectification mode and a voltage-multiplying rectification mode;
the primary side half-bridge LLC resonant circuit 10 is composed of a primary side first switching tube S1Primary side second switch tube S2Resonant capacitor CrResonant inductor LrAnd an excitation inductance LmComposition is carried out;
the secondary hybrid rectifier circuit 20 is composed of a secondary first rectifier diode D1And a secondary side second rectifier diode D2And a secondary side third rectifier diode D3And a secondary fourth rectifier diode D4And a third secondary switch tube S3And a secondary side fourth switch tube S4A secondary side first output filter capacitor Co1And a secondary side second output filter capacitor Co2Composition is carried out;
primary side first switching tube S of primary side half-bridge LLC resonant circuit 101Is connected to a DC input source VinThe positive end of (1), the primary side first switch tube S1Is connected to the second switching tube S on the primary side2Drain electrode and resonant capacitor CrOne terminal of (1), a resonance capacitor CrIs connected at the other end to a resonant inductor LrOne terminal of (1), resonant inductor LrIs connected to the excitation inductance L at the other endmAnd primary winding N of transformer TPEnd of same name, primary winding N of transformer TPIs connected to the excitation inductor LmAnother end of the primary side second switch tube S2Source and dc input source VinA negative terminal of (a);
the secondary winding N of the transformer TSIs connected to a first rectifier diode D on the secondary side1Anode and secondary side third rectifying diode D3Cathode of (2), secondary side first rectifying diode D1Cathode of the first rectifying diode is connected to the secondary side of the second rectifying diode D2Cathode and secondary side first output filter capacitor Co1And an output load RoOne end of (1), output load RoThe other end of the first output filter capacitor is connected with a secondary side second output filter capacitor Co2One end, secondary side third rectifying diode D3Anode and secondary side fourth rectifier diode D4The anode of (1), the secondary side first output filter capacitor Co1The other end of the first output filter capacitor is connected with a secondary side second output filter capacitor Co2And the other end of the secondary side of the fourth switching tube S4Drain electrode of transformer T, secondary winding N of transformer TSIs connected with a second rectifier diode D on the secondary side2Anode and secondary side fourth rectifier diode D4And a third secondary side switching tube S3The drain electrode of the third switching tube S3Is connected with the secondary side of the fourth switch tube S4Of the substrate.
And, for distributed power systems.
The invention also provides a control method of the resonant converter based on the hybrid rectification structure, which is used for the resonant converter of the hybrid rectification structure and adopts a narrow-frequency-range frequency conversion control mode, a fixed-frequency PWM control mode or a variable-frequency pulse width modulation control mode.
Moreover, when the frequency conversion control mode with narrow frequency range is adopted, the following is realized,
the primary side first switch tube S1Switching frequency and primary side second switching tube S2Has the same switching frequency, and has a primary side first switching tube S1And the primary side second switch tube S2Complementary conducting, secondary side third switch tube S3And a secondary side fourth switching tube S4The secondary side hybrid rectification circuit 20 is completely switched off in the whole period and works in a full-bridge rectification mode;
regulating a primary side first switching tube S1And a primary side second switching tube S2The switching frequency of the voltage-regulating circuit regulates the voltage gain, the lower the switching frequency is, the larger the output voltage gain is, and when the switching frequency reaches the lowest frequency, the highest output voltage gain is obtained; at this time, the secondary side third switch tube S3And a secondary side fourth switching tube S4Complementary conducting secondary side fourth switch tube S4First switch tube S connected with primary side1Simultaneously conducted, secondary side third switch tube S3Second opening from primary sideClosing pipe S2Meanwhile, the secondary side hybrid rectification circuit 20 is switched from a full-bridge rectification mode to a voltage-multiplying rectification mode;
primary side first switch tube S is regulated again1And a primary side second switching tube S2The switching frequency of (1) adjusts the voltage gain, the lower the switching frequency, the larger the output voltage gain, and when the switching frequency is the lowest, the highest output voltage gain.
Moreover, when the fixed frequency PWM control mode is adopted, the following is realized,
the primary side first switch tube S1Switching frequency and primary side second switching tube S2Has a switching frequency equal to the resonance frequency, and a primary side first switching tube S1And the primary side second switch tube S2Complementary conduction is carried out, and the primary side half-bridge LLC resonant circuit 10 works at the optimal efficiency point;
secondary third switch tube S3And a secondary side fourth switching tube S4A secondary side third switch tube S controlled by PWM3And a secondary side fourth switching tube S4The duty ratio of (D) is equal, and is marked as D3 ═ D4;
primary side first switch tube S1When the conduction duty ratio is Da, the secondary side third switching tube S3And a secondary side fourth switching tube S4The secondary side hybrid rectification circuit 20 is completely switched off within the time of the duty ratio Da and works in a full-bridge rectification mode; after the duty ratio Da, the secondary side fourth switching tube S4The on duty ratio is D4, D4 is 0.5-Da, and the secondary side hybrid rectification circuit 20 works in a voltage-doubling rectification mode;
secondary fourth switch tube S4After the duty ratio D4 is switched on, the first switch tube S on the primary side1And a secondary side fourth switching tube S4Turn-off, primary side second switch tube S2And a secondary side third switch tube S3Conducting and secondary side third switch tube S3The on duty ratio is D3, D3 is D4, and the secondary side hybrid rectification circuit 20 keeps working in the voltage-doubling rectification mode;
secondary third switch tube S3After the duty ratio D3 is switched on, the secondary side third switching tube S3The secondary side hybrid rectification circuit 20 is switched to a full-bridge rectification mode;
therefore, the duty ratio of the voltage-doubler rectification mode of the secondary hybrid rectifier circuit 20 is D3+ D4 — 2D3 — 2D4, and the larger the duty ratio of the voltage-doubler rectification mode of the secondary hybrid rectifier circuit 20 is, the higher the output voltage gain is.
The technical difference between the technology of the invention and the existing technical scheme is that the rectification side of the resonance converter is combined with a full-bridge rectification circuit and a voltage-multiplying rectification circuit, a bidirectional switch is added, the converter can work in a full-bridge rectification mode and also can work in a voltage-multiplying rectification mode, the control scheme of the resonance converter can adopt a frequency conversion control method with a narrow frequency range and also can adopt a fixed frequency PWM control method, the adjustment of voltage gain in a wide range can be realized, and the voltage adjustment range is wide. The two control methods reduce the switching frequency variation range of the primary side switching tube, are beneficial to the design of magnetic components, improve the voltage gain range, efficiency and power density of the converter and meet the requirement of wide voltage gain range conversion occasions.
The invention has the following beneficial and excellent effects:
(1) the control mode can adopt a variable frequency control method, a fixed frequency PWM control method and a variable frequency PWM control method, and is flexible and good in selectivity;
(2) the design of the converter can be optimized by adopting a fixed-frequency PWM control method;
(3, the voltage gain range is wide, and the method is suitable for application occasions with wide voltage gain range requirements;
(4) the magnetic integration design of magnetic components is facilitated, the volume of the magnetic components is reduced, and the power density is improved.
Drawings
FIG. 1 is a schematic diagram of a resonant converter in accordance with an embodiment of the present invention;
FIG. 2 is a gain curve diagram of a narrow frequency range frequency conversion control of a resonant converter in accordance with an embodiment of the present invention;
FIG. 3 is a diagram of the main operating waveforms of the resonant converter controlled by the fixed-frequency PWM according to the embodiment of the present invention;
FIG. 4 is an equivalent circuit diagram of the switching mode in the working mode 1 when the resonant converter employs fixed-frequency PWM control according to the embodiment of the present invention;
FIG. 5 is an equivalent circuit diagram of the switching mode in the operating mode 2 when the resonant converter employs fixed-frequency PWM control according to the embodiment of the present invention;
fig. 6 is an equivalent circuit diagram of a switching mode in the working mode 3 when the resonant converter adopts the fixed-frequency PWM control according to the embodiment of the present invention;
FIG. 7 is an equivalent circuit diagram of the switching mode in the operating mode 4 when the resonant converter employs fixed-frequency PWM control according to the embodiment of the present invention;
FIG. 8 is an equivalent circuit diagram of the switching mode in the working mode 5 when the resonant converter employs fixed-frequency PWM control according to the embodiment of the present invention;
fig. 9 is an equivalent circuit diagram of the switching mode in the operating mode 6 when the resonant converter adopts the fixed-frequency PWM control according to the embodiment of the present invention.
Detailed Description
The technical solutions of the present invention are described below with reference to the accompanying drawings and examples so that those skilled in the art can better understand the present invention.
The invention provides a resonant converter based on a hybrid rectification structure and a control method for application occasions with wide voltage gain range. The voltage gain of 2 or more is considered to be a wide voltage range. The rectification side of the resonant converter is combined with the full-bridge rectification circuit and the voltage-multiplying rectification circuit, and the bidirectional switch is added, so that the converter can work in a full-bridge rectification mode and can also work in a voltage-multiplying rectification mode. In the control mode, frequency conversion control within a narrow frequency range can be adopted, and Pulse Width Modulation (PWM) control with fixed frequency can also be adopted, so that the magnetic integration design of the magnetic element is facilitated.
As shown in FIG. 1, the resonant converter provided by the embodiment is composed of a DC input source VinPrimary side half-bridge LLC resonant circuit 10, transformer T, secondary side hybrid rectifying circuit 20 and output resistance load RoAnd (4) forming.
Wherein, the primary side half-bridge LLC resonant circuit 10 is composed of a primary side first switch tube S1Primary side second switch tube S2Resonant capacitor CrResonant inductor LrAnd an excitation inductance LmComposition is carried out;
setting the transformation ratio of the primary side and the secondary side of the transformer T as Np: Ns ═ n: 1;
wherein the content of the first and second substances,
Figure BDA0002378474200000041
Vinis a DC input voltage, VoIs the output voltage of the resistive load Ro. And n:1 represents the ratio of the primary side winding to the secondary side winding of the transformer.
The secondary hybrid rectifier circuit 20 is composed of a secondary first rectifier diode D1And a secondary side second rectifier diode D2And a secondary side third rectifier diode D3And a secondary fourth rectifier diode D4And a third secondary switch tube S3And a secondary side fourth switch tube S4A secondary side first output filter capacitor Co1And a secondary side second output filter capacitor Co2Composition is carried out;
primary side first switching tube S of primary side half-bridge LLC resonant circuit 101Is connected to a DC input source VinThe positive end of (1), the primary side first switch tube S1Is connected to the second switching tube S on the primary side2Drain electrode and resonant capacitor CrOne terminal of (1), a resonance capacitor CrIs connected at the other end to a resonant inductor LrOne terminal of (1), resonant inductor LrIs connected to the excitation inductance L at the other endmAnd primary winding N of transformer TPEnd of same name, primary winding N of transformer TPIs connected to the excitation inductor LmAnother end of the primary side second switch tube S2Source and dc input source VinA negative terminal of (a);
the secondary winding N of the transformer TSIs connected to a first rectifier diode D on the secondary side1Anode and secondary side third rectifying diode D3Cathode of (2), secondary side first rectifying diode D1Cathode of the first rectifying diode is connected to the secondary side of the second rectifying diode D2Cathode and secondary side first output filter capacitor Co1And an output load RoOne end of (1), output load RoThe other end of the first output filter capacitor is connected with a secondary side second output filter capacitor Co2One end, secondary side third rectifying diode D3Anode and secondary fourth rectifying diodePipe D4The anode of (1), the secondary side first output filter capacitor Co1The other end of the first output filter capacitor is connected with a secondary side second output filter capacitor Co2And the other end of the secondary side of the fourth switching tube S4Drain electrode of transformer T, secondary winding N of transformer TSIs connected with a second rectifier diode D on the secondary side2Anode and secondary side fourth rectifier diode D4And a third secondary side switching tube S3The drain electrode of the third switching tube S3Is connected with the secondary side of the fourth switch tube S4Of the substrate.
In the case of the specific implementation thereof,
the voltage gain of the secondary side of the resonant converter in a full-bridge rectification mode is as follows:
Figure BDA0002378474200000051
the voltage gain of the secondary side of the resonant converter in the voltage-doubling rectification mode is as follows:
Figure BDA0002378474200000052
wherein n is the transformation ratio of the primary side and the secondary side of the transformer T, VoIs the output voltage of the converter, VinIs the DC input voltage of the converter, and k is the excitation inductance LmAnd a resonant inductor LrInductance ratio of frIs a resonant capacitor CrAnd a resonant inductor LrResonant frequency at series resonance, fsIs a primary side first switch tube S1And a primary side second switching tube S2Switching frequency of RoIn order to be a resistive load,
Figure BDA0002378474200000053
is the power factor of the load. Output voltage V in two modesoThe value is different, and the output voltage in the voltage-doubling rectification mode is twice of the output voltage in the full-bridge rectification mode.
When the resonant converter is implemented, a narrow frequency range frequency conversion control method can be adopted, and the gain curve of frequency conversion control is as shown in the attached figure 2:
primary side first switch tube S1Switching frequency and primary side second switching tube S2Has the same switching frequency, and has a primary side first switching tube S1And the primary side second switch tube S2Complementary conducting, secondary side third switch tube S3And a secondary side fourth switching tube S4The secondary side hybrid rectifier circuit 20 is completely turned off in the whole period and operates in a full-bridge rectification mode. Control the first switch tube S on the primary side1And a primary side second switching tube S2The switching frequency of (3) adjusts the voltage gain, the lower the switching frequency, the higher the output voltage gain, when the switching frequency is f at the lowestminThe output voltage gain is at most 2. At this time, the secondary side third switch tube S3And a secondary side fourth switching tube S4Complementary conducting secondary side fourth switch tube S4First switch tube S connected with primary side1Simultaneously conducted, secondary side third switch tube S3And the primary side second switch tube S2Meanwhile, the secondary side hybrid rectification circuit 20 is switched from the full-bridge rectification mode to the voltage-multiplying rectification mode, and the primary side first switching tube S is adjusted again1And a primary side second switching tube S2The switching frequency of (1) adjusts the voltage gain, the lower the switching frequency, the larger the output voltage gain, and when the switching frequency is the lowest, the highest output voltage gain. In this control mode, the first switching tube S on the primary side1And a primary side second switching tube S2The voltage gain control circuit works in a narrow frequency range, and voltage gain adjustment in a wide range is achieved.
In FIG. 2, fminAlso represents the minimum switching frequency, f, of the primary side switching tubes/frAnd the normalized frequency is represented, namely the ratio of the switching frequency of the primary side switching tube to the series resonant frequency of the resonant capacitor and the resonant inductor. f. ofmaxRepresenting the maximum switching frequency of the primary side switching tube. f. ofminThe switching frequency of the primary side switching tube corresponding to the voltage gain of 2. f. ofmaxThe switching frequency of the primary side switching tube corresponding to the voltage gain of 1 is equal to the resonant frequency.
In the specific implementation, the formula (1) and the formula (2) are combined, and the mixed rectificationThe converter operates in a voltage-multiplying rectification mode, and the voltage gain of the converter is 2 times that of the full-bridge rectification mode, namely G2＝2G1. The voltage gain of the resonant converter is related to the duty ratio of the secondary side voltage-multiplying rectification mode, and the resonant converter can adopt a fixed-frequency PWM control method to control the duty ratio of the secondary side voltage-multiplying rectification mode to adjust the voltage gain. Primary side first switch tube S1Switching frequency and primary side second switching tube S2Has a switching frequency equal to the resonance frequency, and a primary side first switching tube S1And the primary side second switch tube S2Complementary conduction, the primary half-bridge LLC resonant circuit 10 operates at the optimum efficiency point. Secondary third switch tube S3And a secondary side fourth switching tube S4A secondary side third switch tube S controlled by PWM3And a secondary side fourth switching tube S4The duty cycle of (D) is kept equal, denoted as D3 ═ D4. Primary side first switch tube S1When the duty ratio Da is conducted, the secondary side third switching tube S3And a secondary side fourth switching tube S4And the secondary side hybrid rectification circuit 20 is completely switched off within the time of the duty ratio Da and works in a full-bridge rectification mode. Primary side first switch tube S1After the duty ratio Da is switched on, the secondary side fourth switching tube S4The conduction duty ratio is D4, D4 is 0.5-Da, the secondary side hybrid rectification circuit 20 works in a voltage-doubling rectification mode, and the secondary side fourth switching tube S4After the duty ratio D4 is switched on, the first switch tube S on the primary side1And a secondary side fourth switching tube S4Turn-off, primary side second switch tube S2And a secondary side third switch tube S3Conducting and secondary side third switch tube S3The on duty ratio is D3, D3 is D4, and the secondary hybrid rectifier circuit 20 operates in the voltage-doubler rectifier mode. Secondary third switch tube S3After the duty ratio D3 is switched on, the secondary side third switching tube S3And the secondary side hybrid rectification circuit 20 is switched from the voltage-doubling rectification mode to the full-bridge rectification mode. Therefore, the duty ratio of the voltage-doubling rectification mode of the secondary hybrid rectification circuit 20 is D3+ D4-2D 3-2D 4. It can be seen that the larger the duty ratio of the voltage-doubler rectification mode of the secondary hybrid rectification circuit 20, the higher the voltage gain of the converter, and the wider the voltage regulation range. In specific implementation, the value of Da can be selected according to the fourth switch of the secondary sideThe conduction duty ratio D4 of the tube S4 is determined, i.e., according to the gain requirement.
In the specific implementation, the first switch tube S on the primary side1And the primary side second switch tube S2The switching pulses of (a) need to have a reasonable dead time to ensure that the first switching tube (S) on the primary side1And the primary side second switch tube S2Zero-voltage switch, secondary third switching tube S3And a secondary side fourth switching tube S4There is no need to set any dead time between the switching signals.
In specific implementation, in order to realize the adjustment of the wide gain range of the converter, the invention improves the traditional secondary side rectifying circuit on the basis of the traditional half-bridge LLC resonant converter, and the secondary side hybrid rectifying circuit 20 is combined with a full-bridge rectifying circuit and a voltage doubling rectifying circuit to form an isolated DC-DC converter with a hybrid rectifying circuit structure. In terms of the control method, the resonant converter may adopt frequency conversion control in a narrow frequency range, may also adopt fixed-frequency PWM control, and may also adopt frequency conversion PWM control (i.e., a control method in which frequency conversion control in a narrow frequency range of the primary side switch and PWM control of the secondary side switch are combined). The control method is convenient for the design of the magnetic element, improves the voltage gain range of the converter, improves the power density and meets the application occasion of wide voltage gain.
Assuming that the switching devices shown in fig. 1 are ideal devices, the operation principle of the resonant converter when the fixed-frequency PWM control method is adopted will be described in detail below, and the main operation waveforms of the converter when the fixed-frequency PWM control method is adopted are shown in fig. 3. Wherein S1And S2Are respectively a primary side first switch tube S1And the primary side second switch tube S2Driving pulse of (S)3And S4Respectively being a secondary side third switch tube S3And a secondary side fourth switching tube S4Drive pulse of iLrAnd iLmRespectively, a current-through resonant inductor LrAnd an excitation inductance LmCurrent of (V)secFor the voltage across the secondary winding of the transformer T, iD1And iD3Respectively flowing through a secondary side first rectifier diode D1And the second sideThree rectifier diodes D3Current of (d), t0、t1、t2、t3、t4、t5、t6For time, the resonant converter has 6 operation modes in a switching period.
Working mode 1[ t ]0-t1]：t0First switch tube S on primary side1Conducting, primary side second switch tube S2In the off state, the secondary side third switch tube S3And a secondary side fourth switching tube S4Are all in an off state. In mode 1, the secondary side hybrid rectifier circuit operates in a full-bridge rectification mode, and the resonant inductor LrAnd a resonance capacitor CrResonance and excitation inductance LmIs output voltage clamp at nVOSecondary side first rectifier diode D not participating in resonance1And a secondary side fourth rectifying diode D4On and the input terminal transfers energy to the load side.
Mode of operation 2[ t ]1-t2]：t1At the moment, the secondary side fourth switch tube S4The conducting secondary side hybrid rectifying circuit works in a voltage-multiplying rectifying mode, and the resonant inductor LrAnd a resonance capacitor CrResonance and excitation inductance LmSecondary side first output filter capacitor Co1Does not participate in resonance, the rising gradient of the exciting current is reduced, and the voltage clamping of (d) is at t2First switch tube S on primary side1And the shutdown and the operation mode 2 ends.
Working mode 3[ t ]2-t3]: working mode 3 is that the primary side first switch tube S1And the primary side second switch tube S2The dead time in between, this phase is very short. t is t2At the moment, the secondary side fourth switch tube S4Turn-off, secondary side third switch tube S3Conducting, primary side first switch tube S1Turn off, the resonant current is decreased to equal the exciting current, and the first rectifier diode D on the secondary side1The current naturally drops to zero. Primary side first switch tube S1And a primary side second switching tube S2The parasitic capacitances of (a) are charged and discharged, respectively.
Working mode 4[ t ]3-t4]：t3Second switch tube S on primary side2Conducting, in this mode, the secondary side hybrid rectification circuit operates in the voltage doubling rectification mode, and the resonant inductor LrAnd a resonance capacitor CrResonance and excitation inductance LmSecondary side second output filter capacitor Co2Voltage clamping of the secondary side third rectifier diode D without participating in resonance3On and the input terminal transfers energy to the load side.
Working mode 5[ t ]4-t5]：t4At any moment, the secondary side third switching tube S3Turn-off, secondary side second rectifier diode D2On, the secondary side of the hybrid rectification circuit works in a full-bridge rectification mode, and the resonant inductor LrAnd a resonance capacitor CrResonance and excitation inductance LmClamped by the output voltage, not participating in resonance, t5At the moment, the resonant current is equal to the exciting current, and the secondary side second rectifier diode D2And a secondary third rectifying diode D3The current naturally drops to zero and is switched off, and this mode of operation ends.
Working mode 6[ t ]5-t6]：t5Second switch tube S on primary side2Turn-off, enter dead time, primary side first switch tube S1And a primary side second switching tube S2The parasitic capacitances of (a) are discharged and charged, respectively, and this mode time is very short. Resonant inductor LrAnd a resonance capacitor CrAnd excitation inductance LmResonance occurs together, the resonance current being equal to the excitation current, at t6First switch tube S on primary side1Conduction is performed and the operation mode is ended. Output load RoThe output voltage of the secondary side is a first output filter capacitor Co1Voltage and secondary side second output filter capacitor Co2The sum of the voltages.
The specific examples described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made or substituted in a similar manner to the specific embodiments described herein by those skilled in the art without departing from the spirit of the invention or exceeding the scope thereof as defined in the appended claims.

Claims (2)

1. A resonant converter based on a hybrid rectification structure is characterized in that: from a DC input source (V)in) The primary side half-bridge LLC resonant circuit (10), the transformer (T), the secondary side hybrid rectifying circuit (20) and the output resistor load (R)o) The working mode of the secondary side hybrid rectification circuit (20) can be switched between a full-bridge rectification mode and a voltage-multiplying rectification mode;
the primary side half-bridge LLC resonant circuit (10) is composed of a primary side first switching tube (S)1) A primary side second switch tube (S)2) Resonant capacitor (C)r) Resonant inductor (L)r) And excitation inductance (L)m) Composition is carried out;
the secondary side mixed rectification circuit (20) is composed of a secondary side first rectification diode (D)1) And a secondary side second rectifier diode (D)2) And a secondary side third rectifying diode (D)3) And a secondary side fourth rectifier diode (D)4) And a third secondary switch tube (S)3) And a secondary side fourth switching tube (S)4) A secondary side first output filter capacitor (C)o1) And a secondary side second output filter capacitor (C)o2) Composition is carried out;
a primary side first switching tube (S) of the primary side half-bridge LLC resonant circuit (10)1) Is connected to a DC input source (V)in) Positive terminal of (1), primary side first switch tube (S)1) Is connected to the second switching tube (S) on the primary side2) Drain electrode and resonance capacitance (C)r) One terminal of (C), a resonant capacitor (C)r) Is connected to the resonant inductor (L) at the other endr) One terminal of (1), resonant inductance (L)r) Is connected to the excitation inductance (L)m) And a primary winding (N) of the transformer (T)P) End of same name, primary winding (N) of transformer (T)P) Is connected to the excitation inductor (L)m) Another end of the primary side second switch tube (S)2) Source and dc input source (V)in) A negative terminal of (a);
the secondary winding (N) of the transformer (T)S) Is connected to a first rectifier diode (D) on the secondary side1) And a secondary side third rectifying diode (D)3) Secondary side first rectificationPolar tube (D)1) Is connected to a secondary second rectifier diode (D)2) Cathode, secondary side first output filter capacitor (C)o1) And an output load (R)o) One end of (1), output load (R)o) The other end of the first output filter capacitor is connected with a second output filter capacitor (C) of the secondary sideo2) One end, secondary side third rectifying diode (D)3) And a secondary side fourth rectifying diode (D)4) And a secondary side first output filter capacitor (C)o1) The other end of the first output filter capacitor is connected with a second output filter capacitor (C) of the secondary sideo2) And the other end of the secondary side fourth switching tube (S)4) Drain electrode of (1), secondary winding (N) of transformer (T)S) Is connected to a secondary second rectifier diode (D)2) Anode and secondary side fourth rectifying diode (D)4) And a secondary side third switching tube (S)3) Drain electrode of (1), secondary side third switching tube (S)3) Is connected to the secondary side fourth switch tube (S)4) A source electrode of (a);
a narrow frequency range frequency conversion control mode, a fixed frequency PWM control mode or a variable frequency pulse width modulation control mode is adopted;
when the frequency conversion control mode with narrow frequency range is adopted, the following is realized,
the primary side first switch tube (S)1) And the primary side second switching tube (S)2) Has the same switching frequency, and the primary side first switching tube (S)1) And the second switching tube (S) on the primary side2) Complementary conducting, secondary side third switch tube (S)3) And a secondary side fourth switching tube (S)4) The secondary side hybrid rectification circuit (20) is completely switched off in the whole period and works in a full-bridge rectification mode;
regulating the first switching tube (S) on the primary side1) And a primary side second switching tube (S)2) The switching frequency of the voltage-regulating circuit regulates the voltage gain, the lower the switching frequency is, the larger the output voltage gain is, and when the switching frequency reaches the lowest frequency, the highest output voltage gain is obtained; at this time, the secondary side third switching tube (S)3) And a secondary side fourth switching tube (S)4) Complementary conducting, secondary side fourth switch tube (S)4) And the first switch tube (S) on the primary side1) Simultaneously conducted, the secondary side third switch tube (S)3) Second switch tube connected with primary side(S2) Meanwhile, the secondary side hybrid rectification circuit (20) is switched to a voltage-multiplying rectification mode from a full-bridge rectification mode;
readjusting the primary first switching tube (S)1) And a primary side second switching tube (S)2) The switching frequency of the voltage-regulating circuit regulates the voltage gain, the lower the switching frequency is, the larger the output voltage gain is, and when the switching frequency is the lowest, the highest output voltage gain is;
when a fixed frequency PWM control mode is adopted, the following is realized,
the primary side first switch tube (S)1) And the primary side second switching tube (S)2) Is equal to the resonant frequency, a first switching tube (S) on the primary side1) And the second switching tube (S) on the primary side2) Complementary conduction is carried out, and the primary side half-bridge LLC resonant circuit (10) works at the optimal efficiency point;
third switch tube of secondary side (S)3) And a secondary side fourth switching tube (S)4) Adopting PWM control, the secondary side third switch tube (S)3) And a secondary side fourth switching tube (S)4) The duty ratio of (D) is equal, and is marked as D3 ═ D4;
primary side first switch tube (S)1) When the conduction duty ratio is Da, the secondary side third switching tube (S)3) And a secondary side fourth switching tube (S)4) The secondary side hybrid rectification circuit (20) is completely switched off within the time of the duty ratio Da and works in a full-bridge rectification mode; after the duty ratio Da, the fourth switch tube (S) on the secondary side4) The conduction duty ratio is D4, D4 is 0.5-Da, and the secondary side hybrid rectification circuit (20) works in a voltage-doubling rectification mode;
secondary fourth switch tube (S)4) After the duty ratio D4 is switched on, the first switch tube on the primary side (S)1) And a secondary side fourth switching tube (S)4) Turn-off, primary side second switch tube (S)2) And a secondary side third switching tube (S)3) Conducting, secondary side third switch tube (S)3) The conduction duty ratio is D3, D3 is D4, and the secondary side hybrid rectifying circuit (20) keeps working in a voltage-doubling rectifying mode;
third switch tube of secondary side (S)3) After the duty ratio D3 is switched on, the secondary side third switching tube (S)3) The secondary side hybrid rectification circuit (20) is switched to a full-bridge rectification mode after being switched off;
therefore, the duty ratio of the voltage-doubling rectification mode of the secondary side hybrid rectification circuit (20) is D3+ D4-2D 3-2D 4, and the larger the duty ratio of the voltage-doubling rectification mode of the secondary side hybrid rectification circuit (20), the higher the output voltage gain.
2. The resonant converter based on a hybrid rectification structure according to claim 1, characterized in that: the method is used for the distributed power system.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP4181380A1 (en) * 2021-11-15 2023-05-17 Silergy Semiconductor Technology (Hangzhou) Ltd Switching power supply circuit

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP4164106A4 (en) * 2020-06-29 2023-07-12 Huawei Digital Power Technologies Co., Ltd. Resonant converter, and voltage conversion method
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WO2024031552A1 (en) * 2022-08-11 2024-02-15 华为数字能源技术有限公司 Direct-current converter, communication device and photovoltaic system

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101335485A (en) * 2007-06-27 2008-12-31 三星Sdi株式会社 Soft start circuit and power supply including soft start circuit
JP2014011940A (en) * 2012-07-03 2014-01-20 Tdk Corp Current resonant dc-dc converter
JP2015012786A (en) * 2013-07-02 2015-01-19 パナソニックＩｐマネジメント株式会社 Bidirectional dc/dc converter and bidirectional power converter
CN204696926U (en) * 2015-06-19 2015-10-07 正德职业技术学院 A kind of adjustable compression set LLC resonant converter frequently
CN104980037A (en) * 2015-07-07 2015-10-14 南京航空航天大学 Secondary side adjustment type fixed frequency resonant converter and control method thereof
CN106655793A (en) * 2017-02-07 2017-05-10 南京航空航天大学 Common resonant inductor type wide-input-range LLC resonant converter

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107342688B (en) * 2016-04-29 2020-01-17 华为技术有限公司 Resonant power converter and frequency tracking method thereof
CN110601543B (en) * 2019-09-11 2020-08-18 广州金升阳科技有限公司 Wide gain control method of LLC resonant converter and resonant converter thereof

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101335485A (en) * 2007-06-27 2008-12-31 三星Sdi株式会社 Soft start circuit and power supply including soft start circuit
JP2014011940A (en) * 2012-07-03 2014-01-20 Tdk Corp Current resonant dc-dc converter
JP2015012786A (en) * 2013-07-02 2015-01-19 パナソニックＩｐマネジメント株式会社 Bidirectional dc/dc converter and bidirectional power converter
CN204696926U (en) * 2015-06-19 2015-10-07 正德职业技术学院 A kind of adjustable compression set LLC resonant converter frequently
CN104980037A (en) * 2015-07-07 2015-10-14 南京航空航天大学 Secondary side adjustment type fixed frequency resonant converter and control method thereof
CN106655793A (en) * 2017-02-07 2017-05-10 南京航空航天大学 Common resonant inductor type wide-input-range LLC resonant converter

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP4181380A1 (en) * 2021-11-15 2023-05-17 Silergy Semiconductor Technology (Hangzhou) Ltd Switching power supply circuit

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