CN115425838A - Non-isolated LLC resonant converter - Google Patents
Non-isolated LLC resonant converter Download PDFInfo
- Publication number
- CN115425838A CN115425838A CN202211056886.2A CN202211056886A CN115425838A CN 115425838 A CN115425838 A CN 115425838A CN 202211056886 A CN202211056886 A CN 202211056886A CN 115425838 A CN115425838 A CN 115425838A
- Authority
- CN
- China
- Prior art keywords
- resonant
- switching unit
- transformer
- inductor
- bridge
- 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
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
- H02M3/01—Resonant DC/DC converters
-
- 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
- H02M1/08—Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters
- H02M1/083—Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters for the ignition at the zero crossing of the voltage or the current
-
- 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
-
- 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 non-isolated LLC resonant converter which comprises a first resonant bridge, a second resonant bridge, a resonant network, a rectifier bridge, a transformer, a load and an output capacitor, wherein the transformer comprises a first transformer inductor and a second transformer inductor, and the non-isolated LLC resonant converter is simple in circuit, simple and easy to control and low in cost.
Description
Technical Field
The invention relates to the technical field of power supplies, in particular to a non-isolated LLC resonant converter.
Background
In recent years, with the increase of calculated amount, the electric energy demand of a single board card of a server is larger and larger, particularly with the wide use of a rack server, the current of a direct current power supply bus is larger and larger, and a power supply framework adopting a 48V bus to supply power for the server board card gradually replaces the traditional framework of a 12V bus; the 48V architecture generally converts an ac power supply into a 48V dc bus through an ac power supply, converts the 48V into 12v through a DCDC power supply, converts the 48V into 12v through the 12v, and converts the 48V into various voltages as low as 0.6V required by each chipset to supply power to the chipsets, and also directly converts the 48V into a CPU core voltage of about 1V to supply power to the CPU. Because each chipset in the server system needs low voltage power supply as low as 0.6V, and there are many 12V loads such as fans and memories, the way of converting from 12V to 12V and then from 12V to voltage to supply power to the chipset gradually becomes mainstream.
On one hand, the server market is huge in size and high in cost pressure; on the other hand, the global energy saving and consumption reduction requirement is higher and higher, which makes the low-cost and high-efficiency conversion from 48V to 12V become a very important research direction in the field of power electronics, and many research resources enter the field and many research results are presented in succession. The most widely used are two technical directions: one direction is to optimize the design continuously based on the 48V to 12V module power widely used in the traditional communication field. In recent years, new products are continuously proposed in the direction, and the power density and the efficiency are also improved year by year; most head enterprises adopt isolated half-bridge or full-bridge hard switch circuits, and a small part adopts isolated half-bridge or full-bridge non-isolated LLC resonant converter circuits; in order to achieve higher efficiency and power density, the number of layers and copper thickness of a PCB are continuously increased in the development direction, the design of an isolation transformer is continuously optimized, and a power MOS tube with more excellent performance is selected, so that the cost of a product is continuously increased, the development period is prolonged, the design difficulty and the technical requirements on technical personnel are improved, the development in the direction is a bottleneck, and the performance and the price are difficult to develop in a balanced manner. The other direction is a non-isolated 48V to 12V application and the corresponding Switched Tank converter resonant converter (STC) was first introduced as shown in fig. 4. The converter can realize soft switching of all switching devices through cascade connection of the multi-stage resonant circuits, and the stress of the switching devices is effectively controlled in a mode of series connection of the switching devices and clamping of output voltage, so that the efficiency of the converter is effectively improved at low cost, and the circuit becomes a hotspot in the research field at one time. However, this circuit also has two inherent disadvantages: firstly, the converter is a resonance scheme of a switched capacitor circuit, the relation of input and output voltages is a fixed transformation ratio, voltage regulation cannot be carried out, the application of the converter is greatly limited, and particularly after several head enterprises turn the power supply schemes of the servers to 12V voltage in sequence to be controllable, the attention of the circuit begins to decline; in addition, the number of switching devices is large, the control is complex, the driving scheme and the auxiliary source design are complex due to the fact that the switching devices are connected in series, the realization and the cost of the circuit are increased under the condition that a special analog controller is not arranged, and the application of the circuit is limited to a certain extent. After that, the buck converter circuit shown in fig. 5 is focused again, and a series capacitor is added in the conventional buck converter circuit, so that the duty ratio of the converter can be expanded due to the capacitor, the voltage ripple before the filter inductor is output is greatly reduced, the working condition of the filter inductor is improved, the switching frequency of the converter can be reduced, the switching loss is reduced, the efficiency is improved, and meanwhile, the circuit structure of the converter is simple compared with that of an STC circuit, and the design difficulty is reduced. The circuit is a more optimized scheme in the current non-isolated 48V-to-12V application. The only disadvantage of this circuit is hard switching. Because the switching device is in a hard switching condition during operation, the improvement of the switching frequency of the converter is limited to a certain extent, so that the module is limited to further improve the power density of the power module.
Therefore, there is a need to provide a novel non-isolated LLC resonant converter to solve some of the above problems in the prior art.
Disclosure of Invention
The invention aims to provide a non-isolated LLC resonant converter, which reduces control difficulty and cost.
In order to achieve the above object, the non-isolated LLC resonant converter of the present invention includes a first resonant bridge, a second resonant bridge, a resonant network, a rectifier bridge, a transformer, a load, and an output capacitor, where the transformer includes a first transformer inductor and a second transformer inductor, the first transformer inductor is connected in series with the resonant network to form a transformer resonant unit, a first end of the transformer resonant unit is connected to the first resonant bridge, a second end of the transformer resonant unit is connected to the second resonant bridge, both ends of the second transformer inductor are connected to the rectifier bridge, the rectifier bridge is connected to the first resonant bridge, the second resonant bridge, one end of the load, and one end of the output capacitor, the other end of the load, the other end of the output capacitor, and the rectifier bridge are all connected to a negative electrode of a power supply and grounded, the first resonant bridge is used to connect the first end of the transformer resonant unit to a positive electrode of the power supply or one end of the load, the second resonant bridge is used to connect the second end of the transformer resonant unit to a positive electrode of the power supply or one end of the load, and the rectifier bridge is used to connect the second end of the rectifier bridge to one end of the load and the other end of the rectifier bridge to connect the load.
The non-isolated LLC resonant converter has the beneficial effects that: the transformer comprises a first resonance bridge, a second resonance bridge, a resonance network, a rectifier bridge, a transformer, a load and an output capacitor, and the transformer comprises a first transformer inductor and a second transformer inductor, so that the circuit is simple, the control is simple and easy, and the cost is low.
Optionally, the first resonant bridge includes a first switch unit and a third switch unit, a first end of the first switch unit is connected to the positive electrode of the power supply, a second end of the first switch unit is connected to a first end of the third switch unit, and a second end of the third switch unit is connected to one end of the load.
Optionally, the first switching unit and the third switching unit are controllable switching devices.
Optionally, the second resonant bridge includes a second switch unit and a fourth switch unit, a first end of the second switch unit is connected to the positive electrode of the power supply, a second end of the second switch unit is connected to a first end of the fourth switch unit, and a second end of the fourth switch unit is connected to one end of the load.
Optionally, the second switching unit and the fourth switching unit are both controllable switching devices.
Optionally, the rectifier bridge includes a fifth switch unit, a sixth switch unit, a seventh switch unit, and an eighth switch unit, where a first end of the fifth switch unit and a first end of the sixth switch unit are both connected to one end of the load, a second end of the fifth switch unit is connected to the first end of the seventh switch unit, a second end of the sixth switch unit is connected to the first end of the eighth switch unit, and a second end of the seventh switch and a second end of the eighth switch are both connected to the other end of the load.
Optionally, the fifth switching unit, the sixth switching unit, the seventh switching unit, and the eighth switching unit are controllable switching devices or uncontrollable switching devices.
Optionally, the controllable switch device includes a metal oxide semiconductor field effect transistor, an insulated gate bipolar transistor, a gallium nitride transistor, a silicon carbide MOS transistor, and a first combined switch unit, where the first combined switch unit is a combination of a triode and a diode.
Optionally, the non-controllable switch device comprises a diode and a second combined switch unit, and the second combined switch unit comprises a combination of the diode and any one of a metal oxide semiconductor field effect transistor, an insulated gate bipolar transistor, a gallium nitride transistor and a silicon carbide MOS transistor.
Optionally, the resonant network includes a first resonant inductor and a resonant capacitor, and the first resonant inductor, the resonant capacitor and the first transformer inductor are connected in series.
Optionally, the resonant network further includes a resistor, and the resistor is connected in series with the first resonant inductor, the resonant capacitor, and the first transformer inductor.
Optionally, the transformer further comprises a second resonant inductor, and the second resonant inductor is connected in parallel with the first transformer inductor or the second transformer inductor.
Optionally, the first transformer inductance includes at least one sub-transformer inductance, and the sub-transformer inductances are connected in series.
Drawings
FIG. 1 is a circuit schematic of a non-isolated LLC resonant converter in some embodiments of the invention;
FIG. 2 is a circuit schematic of a non-isolated LLC resonant converter in further embodiments of the invention;
FIG. 3 is a timing diagram of the non-isolated LLC resonant converter of FIG. 1 in some embodiments of the invention;
fig. 4 is a schematic circuit diagram of an STC resonant converter of the prior art;
fig. 5 is a circuit diagram of a buck converter circuit in the prior art.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without inventive step based on the embodiments of the present invention, are within the scope of protection of the present invention. Unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention belongs. As used herein, the word "comprising" and similar words are intended to mean that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items.
In view of the problems in the prior art, embodiments of the present invention provide a non-isolated LLC resonant converter. Referring to fig. 1, the non-isolated LLC resonant converter 100 includes a first resonant bridge 101, a second resonant bridge 102, a resonant network 103, a rectifier bridge 104, a transformer 105, a load Ro, and an output capacitor Co, the transformer 105 including a first transformer inductance N1 and a second transformer inductance N2.
In some embodiments, the first transformer inductor is connected in series with the resonant network to form a transformer resonant unit, a first end of the transformer resonant unit is connected to the first resonant bridge, a second end of the transformer resonant unit is connected to the second resonant bridge, two ends of the second transformer inductor are both connected to the rectifier bridge, the rectifier bridge is connected to the first resonant bridge, the second resonant bridge, one end of the load, and one end of the output capacitor, the other end of the load, the other end of the output capacitor, and the rectifier bridge are all connected to a negative electrode of a power supply and grounded, the first resonant bridge is configured to communicate the first end of the transformer resonant unit with a positive electrode of the power supply or one end of the load, the second resonant bridge is configured to communicate the second end of the transformer resonant unit with a positive electrode of the power supply or one end of the load, and the rectifier bridge is configured to communicate two ends of the second transformer inductor with one end of the load and the other end of the load, respectively.
In some embodiments, the first resonant bridge includes a first switching unit and a third switching unit, a first terminal of the first switching unit is connected to a positive electrode of a power supply, a second terminal of the first switching unit is connected to a first terminal of the third switching unit, and a second terminal of the third switching unit is connected to one terminal of the load.
In some embodiments, the second resonant bridge includes a second switching unit and a fourth switching unit, a first terminal of the second switching unit is connected to the positive electrode of the power supply, a second terminal of the second switching unit is connected to a first terminal of the fourth switching unit, and a second terminal of the fourth switching unit is connected to one terminal of the load.
In some embodiments, the rectifier bridge includes a fifth switch unit, a sixth switch unit, a seventh switch unit, and an eighth switch unit, a first end of the fifth switch unit and a first end of the sixth switch unit are both connected to one end of the load, a second end of the fifth switch unit is connected to a first end of the seventh switch unit, a second end of the sixth switch unit is connected to a first end of the eighth switch unit, and a second end of the seventh switch and a second end of the eighth switch are both connected to the other end of the load.
In some embodiments, the first switching unit, the second switching unit, the third switching unit and the fourth switching unit are all controllable switching devices, and the fifth switching unit, the sixth switching unit, the seventh switching unit and the eighth switching unit are all controllable switching devices or uncontrollable switching devices. Specifically, the controllable switch device includes a metal oxide semiconductor field effect transistor, an insulated gate bipolar transistor, a gallium nitride transistor, a silicon carbide MOS transistor, and a first combined switch unit, the first combined switch unit is a combination of a triode and a diode, the uncontrollable switch device includes a diode and a second combined switch unit, and the second combined switch unit includes a combination of any one of the diode and the metal oxide semiconductor field effect transistor, the insulated gate bipolar transistor, the gallium nitride transistor, and the silicon carbide MOS transistor.
Referring to fig. 1, the first switch unit is a first NMOS transistor S1, the second switch unit is a second NMOS transistor S2, the third switch unit is a third NMOS transistor S3, the fourth switch unit is a fourth NMOS transistor S4, the fifth switch unit is a fifth NMOS transistor S5, the sixth switch unit is a sixth NMOS transistor S6, the seventh switch unit is a seventh NMOS transistor S7, and the eighth switch unit is an eighth NMOS transistor S8.
Referring to fig. 1, a drain of the first NMOS transistor S1 is connected to an anode of the power Vin, a source of the first NMOS transistor S1 is connected to a drain of the third NMOS transistor S3 and a synonym terminal of the first transformer inductor N1, and a source of the third NMOS transistor S3 is connected to one end of the load Ro and one end of the output capacitor Co.
Referring to fig. 1, a drain of the second NMOS transistor S2 is connected to an anode of the power Vin, a source of the second NMOS transistor S4 is connected to a drain of the fourth NMOS transistor S4, and a source of the fourth NMOS transistor S4 is connected to one end of the load Ro and one end of the output capacitor Co.
Referring to fig. 1, a drain of the fifth NMOS tube S5 and a drain of the sixth NMOS tube S6 are both connected to one end of the load Ro, a source of the fifth NMOS tube S5 is connected to a drain of the seventh NMOS tube S7 and a synonym end of the second transformer inductor N2, a source of the sixth NMOS tube S6 is connected to a drain of the eighth NMOS tube S8 and a synonym end of the second transformer inductor N2, and a source of the seventh NMOS tube S7 is connected to a source of the eighth NMOS tube S8, the other end of the load Ro, the other end of the output capacitor Co, and a negative electrode of the power source Vin, and is grounded.
Referring to fig. 1, a gate of the first NMOS transistor S1 is connected to a first control signal, a gate of the second NMOS transistor S2 is connected to a second control signal, a gate of the third NMOS transistor S3 is connected to a third control signal, a gate of the fourth NMOS transistor S4 is connected to a fourth control signal, a gate of the fifth NMOS transistor S5 is connected to a fifth control signal, a gate of the sixth NMOS transistor S6 is connected to a sixth control signal, a gate of the seventh NMOS transistor S7 is connected to a seventh control signal, and a gate of the eighth NMOS transistor S8 is connected to an eighth control signal.
In some embodiments, the resonant network comprises a first resonant inductance and a resonant capacitance, the first resonant inductance, the resonant capacitance and the first transformer inductance being connected in series.
In still other embodiments, the resonant network further comprises a resistor in series with the first resonant inductor, the resonant capacitor, and the first transformer inductor.
In some embodiments, the transformer further comprises a second resonant inductance in parallel with the first transformer inductance or the second transformer inductance. The second resonance inductor is an independent inductor or an excitation inductor of the transformer.
In some embodiments, the first transformer inductance comprises at least one sub-transformer inductance, and the sub-transformer inductances are connected in series.
Referring to fig. 1, the resonant network 103 includes a first resonant inductor Lr and a resonant capacitor Cr, one end of the first resonant inductor Lr is connected to the dotted terminal of the first transformer inductor N1, the other end of the first resonant inductor Lr is connected to one end of the resonant capacitor Cr, the other end of the resonant capacitor Cr is connected to the source of the second NMOS transistor S2, the transformer further includes a second resonant inductor Lm, one end of the second resonant inductor Lm is connected to the dotted terminal of the first transformer inductor N1, and the other end of the second resonant inductor Lm is connected to the dotted terminal of the first transformer inductor N1.
Fig. 2 is a circuit schematic of a non-isolated LLC resonant converter in further embodiments of the present invention. Referring to fig. 2 and 1, fig. 2 differs from fig. 1 in that: and the fifth NMOS transistor S5, the sixth NMOS transistor S6, the seventh NMOS transistor S7 and the eighth NMOS transistor S8 are replaced by diodes.
Fig. 3 is a timing diagram of the non-isolated LLC resonant converter shown in fig. 1 in some embodiments of the invention. Refer to FIG. 3,S 1 Representing a first control signal, S 2 Representing a second control signal, S 3 Denotes a third control signal, S 4 Denotes a fourth control signal, S 5 Denotes a fifth control signal, S 6 Denotes a sixth control signal, S 7 Denotes a seventh control signal, S 8 Denotes an eighth control signal, I Lr Representing the current through the first resonant inductor, I Lm Representing the current through the second resonant inductor, I Ro Representing the current through the load, V S1 Voltage difference V of the source and the drain of the first NMOS tube S2 Voltage difference V of the source and the drain of the second NMOS tube S3 Voltage difference V of source and drain of the third NMOS tube S4 Represents the voltage difference of the source and the drain of the fourth NMOS tube, and S 1 And S 4 Same, S 2 And S 4 Same, S 5 And S 8 Same, S 6 And S 7 Same, V S2 And V S3 Same, V S1 And V S4 The same is true.
Referring to fig. 1 and 3, at a time point between t0 and t1, the first NMOS transistor S1, the fourth NMOS transistor S4, the fifth NMOS transistor S5, and the eighth NMOS transistor S8 are turned on, and the second NMOS transistor S2, the third NMOS transistor S3, the sixth NMOS transistor S6, and the seventh NMOS transistor S7 are turned off, at the time point t0, since the body diode of the first NMOS transistor S1, the body diode of the fourth NMOS transistor S4, the body diode of the fifth NMOS transistor S5, and the body diode of the eighth NMOS transistor S8 are turned on in advance, at this time point, turning on the first NMOS transistor S1, the fourth NMOS transistor S4, the fifth NMOS transistor S5, and the eighth NMOS transistor S8 can realize 0-voltage soft switch turn-on; the number of turns of the first transformer inductor N1 and the second transformerThe ratio of the number of turns of the inductor N2 is N:1, therefore, after the first resonant inductor Lr and the resonant capacitor Cr are connected in series, the voltages at the two ends are resonant voltages, and the resonant voltage is a power voltage V in A difference from the (n + 1) -fold output voltage VoVo, wherein under excitation of the resonant voltage, the current flowing through the first resonant inductor rises in a sinusoidal resonance mode and then falls in a resonance mode; the voltage across the second resonant inductor Lm is n times the output voltage VoVo, and the current flowing through the second resonant inductor Lm rises linearly under the excitation of the voltage across the second resonant inductor Lm.
Referring to fig. 1 and 3, at time t0 to t1, the current flowing through the first transformer inductor N1 is a difference between the current flowing through the first resonant inductor Lr and the current flowing through the second resonant inductor Lm, according to the coupling relationship between the first transformer inductor N1 and the second transformer inductor N2, the current flowing through the second transformer inductor N2 is N times the current flowing through the first transformer inductor N1, and the total current injected into the output capacitor Co and the load Ro is a sum of the current flowing through the first transformer inductor N1 and the current flowing through the second transformer inductor N2; at this stage, the voltages at the two ends of the source and the drain of the first NMOS transistor S1, the voltages at the two ends of the source and the drain of the fourth NMOS transistor S4, the voltages at the two ends of the source and the drain of the fifth NMOS transistor S5, and the voltages at the two ends of the source and the drain of the eighth NMOS transistor S8 are all 0V, and the voltages at the two ends of the source and the drain of the second NMOS transistor S2 and the voltages at the two ends of the source and the drain of the third NMOS transistor S3 are all the power supply voltage V in And the difference value of the output voltage VoVo, the voltage at the two ends of the source and the drain of the sixth NMOS transistor S6 and the voltage at the two ends of the source and the drain of the seventh NMOS transistor S7 are both the output voltage VoVo.
Referring to fig. 1 and fig. 3, at a time t1 to Ts/2, at the time t1, the first NMOS transistor S1, the fourth NMOS transistor S4, the fifth NMOS transistor S5, and the eighth NMOS transistor S8 are turned off, the current direction on the first resonant inductor Lr does not change suddenly, and at this time, the current direction on the first resonant inductor Lr is positive, and the junction capacitor of the first NMOS transistor S1, the junction capacitor of the fourth NMOS transistor S4, the junction capacitor of the fifth NMOS transistor S5, and the junction capacitor of the eighth NMOS transistor S8 are charged, and at the same time, the junction capacitor of the second NMOS transistor S2, the junction capacitor of the third NMOS transistor S3, the junction capacitor of the sixth NMOS transistor S6, and the junction capacitor of the seventh NMOS transistor S7 are discharged; before the time Ts/2, after the voltages at the source and the drain of the second NMOS transistor S2, the voltages at the source and the drain of the third NMOS transistor S3, the voltages at the source and the drain of the sixth NMOS transistor S6 and the voltages at the source and the drain of the seventh NMOS transistor S7 are gradually reduced to 0, the body diode of the second NMOS transistor S2, the body diode of the third NMOS transistor S3, the body diode of the sixth NMOS transistor S6 and the body diode of the seventh NMOS transistor S7 are conducted.
Referring to fig. 1 and 3, at time Ts/2 to t2, at time Ts/2, since the body diode of the second NMOS transistor S2, the body diode of the third NMOS transistor S3, the body diode of the sixth NMOS transistor S6, and the body diode of the seventh NMOS transistor S7 are turned on in advance, at this time, turning on the second NMOS transistor S2, the third NMOS transistor S3, the sixth NMOS transistor S6, and the seventh NMOS transistor S7 can achieve 0-voltage turn-on; after the first resonant inductor Lr and the resonant capacitor Cr are connected in series, the voltages at two ends are resonance voltage which is power voltage V in The difference between the voltage and (n + 1) -time output voltage Vovo is that under the excitation of the resonance voltage, the current flowing through the first resonance inductor Lr firstly falls in sinusoidal resonance and then rises in resonance; the voltage across the second resonant inductor Lm is a negative n-fold output voltage VoVo, and the current flowing through the second resonant inductor Lm drops linearly under the excitation of the voltage across the second resonant inductor Lm.
Referring to fig. 1 and 3, at time Ts/2 to t2, the current flowing through the first transformer inductor N1 is the difference between the current flowing through the first resonant inductor Lr and the current flowing through the second resonant inductor Lm; according to the coupling relation between the first transformer inductor N1 and the second transformer inductor N2, the current flowing through the second transformer inductor N2 is N times of the current flowing through the first transformer inductor N1; the total current injected into the output capacitor Co and the load Ro is the current flowing through the first transformer inductor N1 and the current flowing through the second transformer inductor N2The sum of the currents; at this stage, the voltages at the source and the drain of the second NMOS transistor S2, the voltages at the source and the drain of the third NMOS transistor S3, the voltages at the source and the drain of the sixth NMOS transistor S6, and the voltages at the source and the drain of the seventh NMOS transistor S7 are all 0, and the voltages at the source and the drain of the first NMOS transistor S1 and the voltages at the source and the drain of the fourth NMOS transistor S4 are all the power voltage V in And the difference value between the output voltage Vo and the source and drain voltages of the fifth NMOS transistor S5 and the eighth NMOS transistor S8 is the output voltage VoVo.
Referring to fig. 1 and fig. 3, at a time t2 to Ts, at a time t2, the second NMOS transistor S2, the third NMOS transistor S3, the sixth NMOS transistor S6, and the seventh NMOS transistor S7 are turned off, the current flowing through the first resonant inductor Lr does not suddenly change, and at this time, the direction of the current flowing through the first resonant inductor Lr is negative, and the junction capacitor of the second NMOS transistor S2, the junction capacitor of the third NMOS transistor S3, the junction capacitor of the sixth NMOS transistor S6, and the junction capacitor of the seventh NMOS pipe S1 are charged, and the junction capacitor of the fourth NMOS transistor S4, the junction capacitor of the fifth NMOS transistor S5, and the junction capacitor of the eighth NMOS transistor S8 are discharged; before the time Ts, after the voltages at the two ends of the source and the drain of the first NMOS transistor S1, the voltages at the two ends of the source and the drain of the fourth NMOS transistor S4, the voltages at the two ends of the source and the drain of the fifth NMOS transistor S5 and the voltages at the two ends of the source and the drain of the eighth NMOS transistor S8 are gradually reduced to 0, the body diode of the first NMOS transistor S1, the body diode of the fourth NMOS transistor S4, the body diode of the fifth NMOS transistor S5 and the body diode of the eighth NMOS transistor S8 are conducted. At the time of Ts, the first NMOS transistor S1, the fourth NMOS transistor S4, the fifth NMOS transistor S5, and the eighth NMOS transistor S8 are turned on at a voltage of 0, and the non-isolated LLC resonant converter enters the next switching cycle.
Referring to fig. 1 and 3, at times t0 to t1 and times Ts/2 to t2, impedances of the first resonant inductor Lr, the resonant capacitor Cr, and the second resonant inductor Lm vary with an operating frequency, and thus, by adjusting the operating frequency of the non-isolated LLC resonant converter, an adjustment function of injecting the load Ro current and the output voltage Vo can be realized.
The first NMOS tube and the fourth NMOS tube are conducted in phase, the second NMOS tube and the third NMOS tube are conducted in phase, the first NMOS tube and the sixth NMOS tube are conducted in a complementary mode, and the second NMOS tube and the fifth NMOS tube are conducted in a complementary mode. The first resonance inductor and the resonance capacitor can work in a resonance mode by controlling the connection and disconnection of the first NMOS tube, the second NMOS tube, the third NMOS tube and the fourth NMOS tube, so that 0-voltage switching of the first NMOS tube, the second NMOS tube, the third NMOS tube and the fourth NMOS tube is realized by resonance energy, soft switching is realized, high frequency and high efficiency of a power supply are realized, and meanwhile, the circuit is simple, safe, reliable and simple and feasible to control. And forming resonant current by using a resonant network, and realizing voltage change, current reduction of the first transformer inductor and the second transformer inductor and conversion of input voltage to output voltage by using the voltage and current coupling relation of the first transformer inductor and the second transformer inductor of the transformer. The output voltage can be adjusted by adjusting the turn ratio of the first transformer inductor and the second transformer inductor. By adjusting the switching frequency of the non-isolated LLC resonant converter, the output voltage can be adjusted.
Although the embodiments of the present invention have been described in detail hereinabove, it is apparent to those skilled in the art that various modifications and variations can be made to these embodiments. However, it is to be understood that such modifications and variations are within the scope and spirit of the present invention as set forth in the following claims. Moreover, the invention as described herein is capable of other embodiments and of being practiced or of being carried out in various ways.
Claims (13)
1. The non-isolated LLC resonant converter is characterized by comprising a first resonant bridge, a second resonant bridge, a resonant network, a rectifier bridge, a transformer, a load and an output capacitor, wherein the transformer comprises a first transformer inductor and a second transformer inductor, the first transformer inductor is connected with the resonant network in series to form a transformer resonant unit, the first end of the transformer resonant unit is connected with the first resonant bridge, the second end of the transformer resonant unit is connected with the second resonant bridge, two ends of the second transformer inductor are connected with the rectifier bridge, the rectifier bridge is connected with the first resonant bridge, the second resonant bridge, one end of the load and one end of the output capacitor, the other end of the load, the other end of the output capacitor and the rectifier bridge are connected with the negative pole of a power supply and grounded, the first resonant bridge is used for communicating the first end of the transformer resonant unit with the positive pole of the power supply or one end of the load, the second resonant bridge is used for communicating the second end of the transformer resonant unit with the positive pole of the power supply or one end of the load, and the rectifier bridge is used for communicating the two ends of the second transformer resonant unit with the positive pole of the load and the other end of the load.
2. The non-isolated LLC resonant converter of claim 1, wherein said first resonant bridge comprises a first switching unit and a third switching unit, a first terminal of said first switching unit being connected to a positive pole of a power supply, a second terminal of said first switching unit being connected to a first terminal of said third switching unit, a second terminal of said third switching unit being connected to one terminal of said load.
3. The non-isolated LLC resonant converter of claim 2, wherein said first switching unit and said third switching unit are both controllable switching devices.
4. A non-isolated LLC resonant converter according to claim 1, characterized in that the second resonant bridge comprises a second switching unit and a fourth switching unit, a first terminal of the second switching unit being connected to the positive pole of the power supply, a second terminal of the second switching unit being connected to a first terminal of the fourth switching unit, a second terminal of the fourth switching unit being connected to one terminal of the load.
5. A non-isolated LLC resonant converter as claimed in claim 4, wherein said second switching unit and said fourth switching unit are controllable switching devices.
6. The non-isolated LLC resonant converter according to claim 1, wherein the rectifier bridge comprises a fifth switching unit, a sixth switching unit, a seventh switching unit and an eighth switching unit, a first end of the fifth switching unit and a first end of the sixth switching unit are both connected to one end of the load, a second end of the fifth switching unit is connected to a first end of the seventh switching unit, a second end of the sixth switching unit is connected to a first end of the eighth switching unit, and a second end of the seventh switch and a second end of the eighth switch are both connected to the other end of the load.
7. The non-isolated LLC resonant converter of claim 6, wherein said fifth switching unit, said sixth switching unit, said seventh switching unit and said eighth switching unit are controllable switching devices or non-controllable switching devices.
8. A non-isolated LLC resonant converter as claimed in claim 3, 5 or 7, wherein said controllable switching devices comprise a metal oxide semiconductor field effect transistor, an insulated gate bipolar transistor, a gallium nitride transistor, a silicon carbide MOS transistor and a first combined switching unit which is a combination of a triode and a diode.
9. The non-isolated LLC resonant converter of claim 7, wherein said non-controllable switching device comprises a diode and a second combined switching unit comprising a combination of a diode and any one of a MOSFET, an IGBT, a GaN transistor, a SiC MOS transistor.
10. The non-isolated LLC resonant converter of claim 1, wherein said resonant network comprises a first resonant inductor and a resonant capacitor, said first resonant inductor, said resonant capacitor and said first transformer inductor being connected in series.
11. The non-isolated LLC resonant converter of claim 10, wherein said resonant network further comprises a resistor in series with said first resonant inductor, said resonant capacitor, and said first transformer inductor.
12. The non-isolated LLC resonant converter of claim 1, wherein said transformer further comprises a second resonant inductance, said second resonant inductance being in parallel with said first transformer inductance or said second transformer inductance.
13. The non-isolated LLC resonant converter of claim 1, wherein said first transformer inductance comprises at least one sub-transformer inductance, said sub-transformer inductances being connected in series.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211056886.2A CN115425838A (en) | 2022-08-30 | 2022-08-30 | Non-isolated LLC resonant converter |
| PCT/CN2023/102032 WO2024045798A1 (en) | 2022-08-30 | 2023-06-25 | Non-isolated llc resonant converter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211056886.2A CN115425838A (en) | 2022-08-30 | 2022-08-30 | Non-isolated LLC resonant converter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115425838A true CN115425838A (en) | 2022-12-02 |
Family
ID=84201298
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211056886.2A Pending CN115425838A (en) | 2022-08-30 | 2022-08-30 | Non-isolated LLC resonant converter |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN115425838A (en) |
| WO (1) | WO2024045798A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2024045798A1 (en) * | 2022-08-30 | 2024-03-07 | 上海英联电子系统有限公司 | Non-isolated llc resonant converter |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102158096B (en) * | 2011-05-11 | 2013-11-20 | 南京博兰得电子科技有限公司 | Non-isolated resonant converter |
| US11515790B2 (en) * | 2020-07-13 | 2022-11-29 | Delta Electronics (Shanghai) Co., Ltd. | Conversion circuit topology |
| US11705817B2 (en) * | 2021-10-01 | 2023-07-18 | Monolithic Power Systems, Inc. | LLC resonant converter with rectifiers processing partial load current |
| CN114649959A (en) * | 2022-03-29 | 2022-06-21 | 华中科技大学 | Buck-Boost LLC converter based on bipolar symmetrical phase-shift modulation strategy |
| CN114938144A (en) * | 2022-06-08 | 2022-08-23 | 上海英联电子系统有限公司 | Non-isolated LLC resonant converter circuit |
| CN115425838A (en) * | 2022-08-30 | 2022-12-02 | 上海英联电子系统有限公司 | Non-isolated LLC resonant converter |
-
2022
- 2022-08-30 CN CN202211056886.2A patent/CN115425838A/en active Pending
-
2023
- 2023-06-25 WO PCT/CN2023/102032 patent/WO2024045798A1/en unknown
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2024045798A1 (en) * | 2022-08-30 | 2024-03-07 | 上海英联电子系统有限公司 | Non-isolated llc resonant converter |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2024045798A1 (en) | 2024-03-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US9484821B2 (en) | Adjustable resonant apparatus for power converters | |
| Wang | Novel zero-voltage-transition PWM DC-DC converters | |
| US9190911B2 (en) | Auxiliary resonant apparatus for LLC converters | |
| CN102859855B (en) | The DC-DC converter circuit of output voltage conversion is input to for height | |
| US9350260B2 (en) | Startup method and system for resonant converters | |
| US20150131329A1 (en) | Gate Drive Apparatus for Resonant Converters | |
| WO2008020629A1 (en) | Insulation boost type push-pull soft-switching dc/dc converter | |
| Yao et al. | A family of buck-type DC-DC converters with autotransformers | |
| TWI384743B (en) | Multi-phase switching power converting circuit | |
| Wang | New family of zero-current-switching PWM converters using a new zero-current-switching PWM auxiliary circuit | |
| Ellis et al. | The symmetric dual inductor hybrid (SDIH) converter for direct 48V-to-PoL conversion | |
| US10159125B1 (en) | LED power supply device | |
| WO2024045798A1 (en) | Non-isolated llc resonant converter | |
| WO2024045797A1 (en) | Non-isolated resonant converter | |
| WO2024027360A1 (en) | Non-isolated full-bridge cascade converter circuit and control method therefor | |
| WO2021078532A1 (en) | Inverter circuit and method, for example for use in power factor correction | |
| Li et al. | An efficiency-oriented two-stage structure employing partial power regulation | |
| TWI501527B (en) | High voltage ratio interleaved converter with soft-switching using single auxiliary switch | |
| CN1897436A (en) | Current-driven synchronized communtating circuit | |
| US11824450B2 (en) | Power converter with switching power stage circuits connected in parallel | |
| Yang et al. | High frequency and high power density bipolar DC–DC converter with GaN HEMT | |
| WO2019177685A1 (en) | Coupled-inductor cascaded buck convertor with fast transient response | |
| CN112564477A (en) | Conversion circuit with strong voltage reduction capability | |
| Chen et al. | A Novel High Step-Down DC-DC Converter Based on TSC Buck Converter | |
| CN219643800U (en) | DC-DC converter |
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 |