CN113922677B - LLC resonant converter, method and power supply system - Google Patents
LLC resonant converter, method and power supply system Download PDFInfo
- Publication number
- CN113922677B CN113922677B CN202111349896.0A CN202111349896A CN113922677B CN 113922677 B CN113922677 B CN 113922677B CN 202111349896 A CN202111349896 A CN 202111349896A CN 113922677 B CN113922677 B CN 113922677B
- Authority
- CN
- China
- Prior art keywords
- voltage
- switch tube
- controllable switch
- controllable
- llc resonant
- 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.)
- Active
Links
- 238000000034 method Methods 0.000 title claims description 39
- 230000000630 rising effect Effects 0.000 claims abstract description 46
- 239000003990 capacitor Substances 0.000 claims abstract description 16
- 238000004804 winding Methods 0.000 claims abstract description 16
- 238000007789 sealing Methods 0.000 claims abstract description 14
- 238000010586 diagram Methods 0.000 description 8
- 230000001939 inductive effect Effects 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
- H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
- H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/33569—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements
- 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
-
- 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
- H02M1/088—Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters for the simultaneous control of series or parallel connected semiconductor devices
-
- 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 application discloses an LLC resonant converter, comprising: at least one bridge arm, a capacitor, an inductor, a transformer and a controller; at least one bridge arm comprises a controllable switch tube; the capacitor, the inductor and the primary winding of the transformer are connected in series to form an LLC resonant circuit; the LLC resonant circuit is connected with at least one bridge arm; the controller is used for sealing the controllable switch tube when the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube have an intersection point, so that the LLC resonant circuit stops working; and when the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate source voltage of the controllable switch tube have no intersection point, controlling the controllable switch tube to work normally. Because the scheme only samples two voltages, namely the grid source voltage and the voltages at two ends can be used for controlling the controllable switching tube to realize ZVS, the implementation mode is simple, and the wave is sealed in time when the ZVS cannot be realized, the protection speed is higher, and faults caused by too high temperature rise are avoided.
Description
Technical Field
The application relates to the technical field of power electronics, in particular to an LLC resonant converter, a method and a power supply system.
Background
At present, the switching power supply converter is widely applied to various fields due to the advantages of high efficiency, small volume and the like. Since the load is directly used as direct current, the power supply system generally includes a DC/DC converter, and in order to improve the power quality and avoid signal interference, the DC/DC converter mostly adopts an isolated switching power supply, and the DC/DC converter is described by taking an LLC resonant converter as an example.
As the name suggests, an LLC resonant converter includes two L and one C, where one L is the primary winding of the transformer, and two L and one C are connected in series to form a series resonance.
Referring to fig. 1, a schematic diagram of an LLC resonant converter corresponding to a single phase power system is shown.
As can be seen from fig. 1, the capacitor Cr, the inductance Lr and the primary winding Lm are connected in series.
The LLC resonant converters are distinguished according to the circuit topology of the primary side connection of the transformer, and comprise a full-bridge LLC resonant converter and a half-bridge LLC resonant converter. The form of the rectifying circuit connected to the secondary winding of the transformer is not limited, and the secondary rectifying circuit may be implemented by a diode or a controllable switching tube, which is illustrated in fig. 1 as an example.
Since in practice the operating frequency of the LLC resonant converter is particularly high during power conversion, i.e. the switching frequency of the switching tube on the primary side is particularly high, typically in the hundreds of kHz. Therefore, in order to reduce power consumption and ensure the safety of the switching tube, the switching tube on the primary side is required to realize zero-voltage switching (ZVS, zero VoltageSwitch), namely, the switching tube can be conducted when the voltage at two ends of the switching tube is close to 0V, so that the loss is minimum. If the switching tube cannot realize ZVS, the switching frequency is higher, high heat is accumulated quickly, the temperature rises suddenly, the switching tube is damaged, normal operation cannot be realized, and the whole power supply system is scrapped.
Therefore, it is necessary to ensure that the LLC resonant converter is in operation, ensuring that the switching tube is capable of ZVS.
Disclosure of Invention
In order to solve the technical problems, the application provides an LLC resonant converter, a method and a power supply system, which can ensure that a switching tube in the LLC resonant converter realizes ZVS so that the LLC resonant converter can work normally.
In order to achieve the above object, the technical solution provided by the embodiments of the present application is as follows:
the application provides an LLC resonant converter comprising: at least one bridge arm, a capacitor, an inductor, a transformer and a controller; at least one bridge arm comprises a controllable switch tube; the capacitor, the inductor and the primary winding of the transformer are connected in series to form an LLC resonant circuit;
the LLC resonant circuit is connected with at least one bridge arm;
the controller is used for sealing the controllable switch tube when the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube have an intersection point, so that the LLC resonant circuit stops working; and when the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate source voltage of the controllable switch tube have no intersection point, controlling the controllable switch tube to work normally.
Preferably, the controller is specifically configured to seal the controllable switch tube when the falling edge of the voltage at two ends of the controllable switch tube determines that the gate-source voltage of the controllable switch tube is greater than the threshold voltage of the controllable switch tube.
Preferably, the controller is specifically configured to control the controllable switching tube to work normally when the falling edge of the voltage at two ends of the controllable switching tube determines that the gate-source voltage of the controllable switching tube is smaller than a preset voltage, where the preset voltage is smaller than a threshold voltage of the controllable switching tube.
Preferably, the controller is further configured to, when determining that the gate-source voltage of the controllable switching tube is greater than a preset voltage and less than a threshold voltage at a falling edge of the voltage at two ends of the controllable switching tube, control the switching frequency of the controllable switching tube to be a preset frequency, where the preset frequency is a minimum switching frequency allowed by the controllable switching tube.
Preferably, the controller is further configured to determine that the gain of the LLC resonant converter is in a preset interval after the switching frequency of the controllable switching tube is controlled to be a preset frequency, and control the controllable switching tube to normally operate, and otherwise seal the controllable switching tube.
Preferably, the controller is further configured to capture a falling edge of the voltage across the controllable switching tube.
Preferably, the LLC resonant converter comprises three-phase half-bridge arms;
the controller is specifically configured to obtain voltages at two ends of the controllable switching tube of each bridge arm in the three-phase half-bridge arm, and seal all the controllable switching tubes in the three-phase half-bridge arm when an intersection exists between a falling edge of the voltage at two ends of at least one controllable switching tube in the controllable switching tube of each bridge arm and a rising edge of the gate-source voltage of the controllable switching tube; and when no intersection point exists between the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube, controlling the controllable switch tube in the three-phase half-bridge arm to work normally.
Preferably, the LLC resonant converter comprises a single-phase half-bridge arm;
the controller is specifically configured to obtain voltages at two ends of the controllable switching tube of each bridge arm of the single-phase half-bridge, and seal all the controllable switching tubes of the single-phase half-bridge when a crossing point exists between a falling edge of the voltage at two ends of at least one controllable switching tube and a rising edge of a gate-source voltage of the controllable switching tube in the controllable switching tube of each bridge arm; and when no intersection point exists between the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube, controlling the controllable switch tube in the single-phase half-bridge arm to work normally.
The application also provides a control method of the LLC resonant converter, which comprises at least one bridge arm, a capacitor, an inductor, a transformer and a controller; at least one bridge arm comprises a controllable switch tube; the capacitor, the inductor and the primary winding of the transformer are connected in series to form an LLC resonant circuit; the LLC resonant circuit is connected with at least one bridge arm; the method comprises the following steps:
detecting the voltage at two ends of the controllable switch tube and the gate-source voltage of the controllable switch tube;
when judging that the intersection point exists between the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube, sealing the controllable switch tube to stop the LLC resonant circuit;
and when judging that the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube have no intersection point, controlling the controllable switch tube to work normally.
Preferably, determining that an intersection exists between a falling edge of a voltage at two ends of the controllable switch tube and a rising edge of a gate-source voltage of the controllable switch tube specifically includes:
and when the voltage of the gate source of the controllable switch tube is larger than the threshold voltage of the controllable switch tube, judging that an intersection point exists between the falling edge of the voltage of the controllable switch tube and the rising edge of the gate source voltage of the controllable switch tube.
Preferably, the judging that the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube have no intersection point specifically comprises:
judging that the gate-source voltage of the controllable switch tube is smaller than the preset voltage at the falling edge of the voltage at the two ends of the controllable switch tube, and judging that no intersection point exists between the falling edge of the voltage at the two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube; the preset voltage is smaller than the threshold voltage of the controllable switch tube.
Preferably, the method further comprises: and when the falling edge of the voltage at two ends of the controllable switch tube judges that the gate-source voltage of the controllable switch tube is larger than the preset voltage and smaller than the threshold voltage, controlling the switching frequency of the controllable switch tube to be the preset frequency, wherein the preset frequency is the minimum switching frequency allowed by the controllable switch tube.
Preferably, the method further comprises: and after the switching frequency of the controllable switching tube is controlled to be the preset frequency, judging that the gain of the LLC resonant converter is in a preset interval, and controlling the controllable switching tube to normally operate, otherwise, sealing the controllable switching tube.
The present application also provides a power supply system including: a rectifying circuit and an LLC resonant converter of any of claims 1-8;
the input end of the rectifying circuit is used for being connected with alternating current;
the output end of the rectifying circuit is connected with the input end of the LLC resonant converter.
According to the technical scheme, the application has the following beneficial effects:
according to the LLC resonant converter provided by the application, the controller determines whether to seal the controllable switch tube or not by judging the voltage at the two ends and the grid source voltage of the controllable switch tube, specifically, when the falling edge of the voltage at the two ends of the controllable switch tube and the rising edge of the grid source voltage of the controllable switch tube have an intersection point, the controllable switch tube is sealed, because the fact that the voltage at the two ends of the controllable switch tube does not fall to 0 at this time is explained, the grid source voltage is started to rise, and at the moment, the controllable switch tube is conducted, and ZVS cannot be realized. On the contrary, when the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube have no intersection point, the voltage at two ends is 0, and the gate-source voltage of the controllable switch tube rises, so that the controllable switch tube can be controlled to work normally, and ZVS is realized. The technical scheme provided by the application only samples two voltages, namely, the controllable switching tube can be controlled to realize ZVS by utilizing the gate-source voltage and the voltages at two ends, the implementation mode is simple, and the wave is sealed in time when the ZVS cannot be realized, so that the protection speed is higher, and faults caused by too high temperature rise are avoided.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, and it is obvious that the drawings in the following description are some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of an LLC resonant converter for a single-phase power system;
FIG. 2 is a schematic diagram of a half-bridge LLC resonant DC/DC converter provided by the application;
FIG. 3 is a voltage waveform diagram according to an embodiment of the present application;
FIG. 4 is a diagram of another voltage waveform provided by an embodiment of the present application;
FIG. 5 is a flow chart of a control method of an LLC resonant converter according to an embodiment of the present application;
FIG. 6 is a flow chart of another control method of an LLC resonant converter according to an embodiment of the present application;
fig. 7 is a schematic diagram of a power supply system according to an embodiment of the present application.
Detailed Description
In order to better understand the scheme provided by the embodiment of the present application, before introducing the method provided by the embodiment of the present application, a scenario of application of the scheme of the embodiment of the present application is first described.
In order to enable a person skilled in the art to better understand the technical solution provided by the embodiments of the present application, the working principle of the DC/DC converter is first described below.
The DC/DC converter provided by the embodiment of the application is described by taking an LLC resonant DC/DC converter as an example, and is distinguished according to the circuit topology of primary side connection of a transformer, and can be a full-bridge LLC resonant DC/DC converter or a half-bridge LLC resonant DC/DC converter. The form of the rectifier circuit to which the secondary winding of the transformer is connected is not limited.
Referring to fig. 2, the schematic diagram of a half-bridge LLC resonant DC/DC converter according to the present application is shown.
The LLC resonant DC/DC converter has the working principle that the input direct current is converted into alternating current, the alternating current is transmitted to a rectifying circuit at an output end through a transformer T, the rectifying circuit rectifies the direct current into direct current and then outputs the direct current, and the direct current is isolated through the transformer T, so that the LLC resonant DC/DC converter can play a role in isolating interference signals, and the interference signals of a primary winding of the transformer T are not transmitted to a secondary winding of the transformer T.
The primary winding of the transformer in fig. 2 comprises an excitation winding Lm; the resonant inductance Lr and the resonant capacitance Cr are connected in series with the primary winding of the transformer T to form LLC resonance. In fig. 2, which is described by taking a three-phase half-bridge as an example, the input end of the LLC resonant DC/DC converter is connected to direct current, that is, a positive direct current bus vbus+ and a negative direct current bus Vbus-, vbus+ and Vbus-are directly connected to a bus capacitor C, where Iar represents the output current of a single bridge arm. As can be seen from fig. 2, the LLC resonant converter outputs direct current, the current being Idc, and a positive voltage vout+ and a negative voltage Vout-, wherein a Load is connected between vout+ and Vout-.
Because the switching tube on the bridge arm has higher working frequency when the LLC resonant DC/DC converter works, in order to reduce the power consumption of the switching tube, the switching tube is required to realize ZVS, otherwise, under higher switching frequency, if the switching tube cannot realize ZVS, a large amount of heat is accumulated in a short time, the temperature rises suddenly, and the switching tube is scrapped and cannot work normally.
The LLC resonant converter can be divided into a capacitive region and an inductive region according to the magnitude of the operating frequency.
LLC capacity region: when the operating frequency is lower than the LLC resonant frequency, the resonant cavity is capacitive, the voltage of the capacitive region lags behind the current, and soft switching, ZVS, cannot be realized, so that the LLC resonant converter needs to be prevented from entering the capacitive region to operate.
LLC inductive region: when the working frequency is higher than LLC resonant frequency, the resonant cavity is inductive, the voltage of the inductive area is advanced to the current, so that soft switching, ZVS, can be realized, and LLC can work normally in the inductive area.
In order that the above-recited objects, features and advantages of the present application will become more readily apparent, a more particular description of embodiments of the application will be rendered by reference to the appended drawings and appended drawings.
The LLC resonant converter provided in this embodiment includes: at least one bridge arm, a capacitor, an inductor, a transformer and a controller; the at least one bridge arm comprises a controllable switch tube; the capacitor, the inductor and the primary winding of the transformer are connected in series to form an LLC resonant circuit;
the LLC resonant circuit is connected with the at least one bridge arm; for example, fig. 2 is described by taking three phases as an example, and includes three bridge arms, and the upper bridge arm and the lower bridge arm of each bridge arm include a switching tube, and fig. 2 is described by taking only one switching tube as an example. The following description will be made by taking any one of the switching tubes to be controlled as an example, and the principle of the other switching tubes is similar when the switching tubes need to be controlled to act, and the description will not be made.
The controller is used for sealing the controllable switch tube when the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube have an intersection point, so that the LLC resonant circuit stops working; and when the falling edge of the voltage at two ends of the controllable switch tube and the grid driving voltage of the controllable switch tube have no intersection point, controlling the controllable switch tube to work normally.
The wave-blocking in this embodiment means that the controllable switching tube is stopped to be driven, i.e. the output of the driving pulse signal, such as PWM signal, is stopped.
In fig. 2, the switching tubes of each bridge arm are taken as MOS tubes as an example, and the voltage at two ends of the controllable switching tube is the voltage between the drain D and the source S, that is, vds; the gate-source voltage of the controllable switch tube is the voltage between the gate G and the source S, namely Vgs. Switching on at ZVS means that Vds is operated when it is 0, and that Vds is not operated when it is not 0. The switching tube is driven to operate only when Vgs is required to be larger than or equal to the threshold voltage of the switching tube, and the switching tube is not conducted if Vgs is smaller than the threshold voltage. From the waveform analysis of the voltage, the ZVS is realized by the switching tube, the voltage at two ends is required to be reduced to 0, namely, the falling edge is ended, the gate-source voltage starts to rise, at the moment, the voltage at two ends is 0, and the gate-source voltage can rise to drive the switching tube to conduct. Conversely, if the falling edge of the voltage across the controllable switching tube has not ended, i.e. the voltage across has not dropped to 0, ZVS may not be achieved when the gate-source voltage has started to rise, and thus the controllable switching tube is not allowed to operate.
According to the technical scheme provided by the embodiment of the application, the controller determines whether to seal the controllable switch tube or not by judging the voltage at the two ends of the controllable switch tube and the grid source voltage, specifically, when the falling edge of the voltage at the two ends of the controllable switch tube and the rising edge of the grid source voltage of the controllable switch tube have an intersection point, the controllable switch tube is sealed, and because the fact that the voltage at the two ends of the controllable switch tube does not fall to 0 at this time is explained, the grid source voltage is started to rise, and at this time, the controllable switch tube is turned on, so that ZVS cannot be realized. On the contrary, when the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube have no intersection point, the voltage at two ends is 0, and the gate-source voltage of the controllable switch tube rises, so that the controllable switch tube can be controlled to work normally, and ZVS is realized. The technical scheme provided by the application only samples two voltages, namely, the controllable switching tube can be controlled to realize ZVS by utilizing the gate-source voltage and the voltages at two ends, the implementation mode is simple, and the wave is sealed in time when the ZVS cannot be realized, so that the protection speed is higher, and faults caused by too high temperature rise are avoided.
The gate-source voltage and the two-terminal voltage of the controllable switch tube are analyzed by combining the drawing.
Referring to fig. 3, a voltage waveform is provided in an embodiment of the present application.
As can be seen from fig. 3, after the falling edge of Vds of the controllable switching tube is finished, the rising edge of Vgs only appears, that is, there is no intersection point between the falling edge of Vds and the rising edge of Vgs, that is, normal action can be performed in this case, so as to realize ZVS.
Referring to fig. 4, another voltage waveform is provided in an embodiment of the present application.
As can be seen from fig. 4, the falling edge of Vds of the controllable switching tube has not yet ended, and the rising edge of Vgs has already started, i.e. there is an intersection point between the falling edge of Vds and the rising edge of Vgs, in which case the controllable switching tube cannot normally operate, and ZVS cannot be realized.
The controller in the embodiment of the application can be a controller of the LLC resonant converter, and the controller can determine whether the controllable switching tube normally acts or stops closing waves according to Vds and Vgs.
Specifically, the controller is specifically configured to seal the controllable switching tube when the gate-source voltage of the controllable switching tube is determined to be greater than the threshold voltage of the controllable switching tube at the falling edge of the voltage at two ends of the controllable switching tube. The gate-source voltage of the controllable switch tube is enough to drive the controllable switch tube to be conducted, the voltage at two ends is not reduced to 0, at the moment, wave sealing is needed, the controllable switch tube is stopped to be driven, the controllable switch tube cannot be conducted, and further the controllable switch tube is prevented from being conducted when the voltage at two ends is not 0.
The controller is specifically used for controlling the controllable switch tube to work normally when the falling edge of the voltage at two ends of the controllable switch tube judges that the gate-source voltage of the controllable switch tube is smaller than the preset voltage, and the preset voltage is smaller than the threshold voltage of the controllable switch tube. The gate-source voltage of the controllable switch tube is small enough to drive the controllable switch tube to be conducted at the falling edge of the voltage at two ends, so that the controllable switch tube can be controlled to work normally. The embodiment of the application is not particularly limited to the value of the preset voltage, and may be 2V, for example. The value can be selected according to the actual situation in the actual product, and the preset voltage is set for keeping a certain margin, so that the state of entering the critical capacitive area is prevented during normal operation.
And the controller is also used for controlling the switching frequency of the controllable switching tube to be a preset frequency when the falling edge of the voltage at two ends of the controllable switching tube judges that the gate-source voltage of the controllable switching tube is larger than a preset voltage and smaller than a threshold voltage, and the preset frequency is the minimum switching frequency allowed by the controllable switching tube. At this time, the controllable switching tube is in a critical state, namely, a critical capacitive region, and can work normally, the current switching frequency of the controllable switching tube is set to be the lowest switching frequency, the LLC resonant converter cannot be continuously frequency-modulated downwards to improve the gain of the LLC resonant converter, and if the gain of the LLC resonant converter cannot meet the requirement at this time, the LLC resonant converter may be damaged or the performance cannot meet the requirement. The switching frequency of the controllable switching tube needs to be controlled in the critical capacitive area, so that the controllable switching tube works at the allowable minimum switching frequency, namely, the switching frequency of the controllable switching tube cannot be reduced any more, and if the switching frequency is reduced any more, the controllable switching tube stops working, namely, enters the capacitive area.
And the controller is also used for judging that the gain of the LLC resonant converter is in a preset interval after the switching frequency of the controllable switching tube is controlled to be a preset frequency, controlling the controllable switching tube to normally operate, and otherwise, sealing the controllable switching tube. That is, in the critical state, it is further necessary to determine whether the gain of the LLC resonant converter is within a preset interval, and if the gain exceeds the preset interval, it is necessary to seal the wave, so that the switching tube stops operating.
The controller is also used for capturing the falling edge of the voltage at two ends of the controllable switch tube, for example, the controller is realized by using a DSP (digital signal processor) which has the function of capturing the rising edge and the falling edge of the pulse signal at present. In addition, when the method is specifically implemented, vds and Vgs can be also fed into two I/O ports of the DSP, and the DSP can compare the relation between the two ports.
The scheme described in the above embodiment is described by taking any one of the switching tubes in the bridge arm as an example, and the technical scheme provided by the embodiment of the application can detect the voltage at two ends and the gate source voltage of the controllable switching tube to be conducted at the same time, and if the voltage of one of the controllable switching tubes does not meet the requirement, the controllable switching tubes of all the bridge arms are subjected to wave sealing so as to ensure the safety of the whole LLC resonant converter. The following description will take three-phase half-bridge arms and single-phase half-bridge arms as examples.
The LLC resonant converter comprises a three-phase half-bridge arm;
the controller is specifically configured to obtain voltages at two ends of the controllable switching tube of each bridge arm of the three-phase half-bridge, and seal all the controllable switching tubes of the three-phase half-bridge when a falling edge of the voltage at two ends of at least one controllable switching tube in the controllable switching tube of each bridge arm has an intersection point with a rising edge of a gate-source voltage of the controllable switching tube; and when the falling edge of the voltage at two ends of the controllable switch tube and the grid driving voltage of the controllable switch tube have no intersection point, controlling the controllable switch tube in the three-phase half-bridge arm to work normally. The application does not limit whether the controllable switching tube is positioned on the upper half bridge arm or the lower half bridge arm of each bridge arm.
The LLC resonant converter comprises a single-phase half-bridge arm;
the controller is specifically configured to obtain voltages at two ends of a controllable switching tube of an upper half bridge arm of each bridge arm of the single-phase half bridge, and seal all the controllable switching tubes of the single-phase half bridge arm when a falling edge of the voltage at two ends of at least one controllable switching tube in the controllable switching tube of the upper half bridge arm of each bridge arm has an intersection point with a rising edge of a gate-source voltage of the controllable switching tube; and when the falling edge of the voltage at two ends of the controllable switch tube and the grid driving voltage of the controllable switch tube have no intersection point, controlling the controllable switch tube in the single-phase half-bridge arm to work normally.
Method embodiment
Based on the LLC resonant converter provided in the above embodiment, an embodiment of the present application further provides a control method, which is described in detail below with reference to the accompanying drawings.
Referring to fig. 5, a flowchart of a control method of an LLC resonant converter according to an embodiment of the application is shown.
According to the control method of the LLC resonant converter, the LLC resonant converter comprises at least one bridge arm, a capacitor, an inductor, a transformer and a controller; at least one bridge arm comprises a controllable switch tube; the capacitor, the inductor and the primary winding of the transformer are connected in series to form an LLC resonant circuit; the LLC resonant circuit is connected with at least one bridge arm; the method comprises the following steps:
s401: detecting the voltage at two ends of the controllable switch tube and the gate-source voltage of the controllable switch tube;
s402: when judging that the intersection point exists between the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube, sealing the controllable switch tube to stop the LLC resonant circuit;
the method for judging the intersection point between the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate source voltage of the controllable switch tube specifically comprises the following steps: and when the voltage of the two ends of the controllable switch tube is larger than the threshold voltage of the controllable switch tube, judging that an intersection point exists between the falling edge of the voltage of the two ends of the controllable switch tube and the rising edge of the voltage of the gate source of the controllable switch tube.
The method for judging whether the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate source voltage of the controllable switch tube have no intersection point specifically comprises the following steps: judging that the gate-source voltage of the controllable switch tube is smaller than the preset voltage at the falling edge of the voltage at the two ends of the controllable switch tube, and judging that no intersection point exists between the falling edge of the voltage at the two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube; the preset voltage is smaller than the threshold voltage of the controllable switch tube.
S403: and when judging that the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube have no intersection point, controlling the controllable switch tube to work normally.
According to the control method provided by the embodiment of the application, whether the controllable switch tube is subjected to wave sealing is determined by judging the voltage at the two ends of the controllable switch tube and the grid source voltage, specifically, when the falling edge of the voltage at the two ends of the controllable switch tube and the rising edge of the grid source voltage of the controllable switch tube have an intersection point, the controllable switch tube is subjected to wave sealing, and because the fact that the voltage at the two ends of the controllable switch tube does not fall to 0 at this time is explained, the grid source voltage is started to rise, and at the moment, the controllable switch tube is conducted, and ZVS cannot be realized. On the contrary, when the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube have no intersection point, the voltage at two ends is 0, and the gate-source voltage of the controllable switch tube rises, so that the controllable switch tube can be controlled to work normally, and ZVS is realized. The technical scheme provided by the application only samples two voltages, namely, the controllable switching tube can be controlled to realize ZVS by utilizing the gate-source voltage and the voltages at two ends, the implementation mode is simple, and the wave is sealed in time when the ZVS cannot be realized, so that the protection speed is higher, and faults caused by too high temperature rise are avoided.
In order to ensure that the controllable switching tube can work safely and ensure that the gain of the LLC resonant converter meets the requirements, the control method provided by the embodiment further comprises: and when the falling edge of the voltage at two ends of the controllable switch tube judges that the gate-source voltage of the controllable switch tube is larger than the preset voltage and smaller than the threshold voltage, controlling the switching frequency of the controllable switch tube to be the preset frequency, wherein the preset frequency is the minimum switching frequency allowed by the controllable switch tube. At this time, the controllable switching tube is in a critical state, namely, a critical capacitive region, and can work normally, the current switching frequency of the controllable switching tube is set to be the lowest switching frequency, the LLC resonant converter cannot be continuously frequency-down-modulated to improve the gain of the LLC resonant converter, and if the gain of the LLC resonant converter cannot meet the requirement at this time, the LLC resonant converter may be damaged or the performance cannot meet the requirement. The switching frequency of the controllable switching tube needs to be controlled in the critical capacitive area, so that the controllable switching tube works at the allowable minimum switching frequency, namely, the switching frequency of the controllable switching tube cannot be reduced any more, and if the switching frequency is reduced any more, the controllable switching tube stops working, namely, enters the capacitive area.
The following describes a specific control method provided in the embodiment of the present application with reference to the accompanying drawings.
Referring to fig. 6, a flowchart of another control method of an LLC resonant converter according to an embodiment of the application is shown.
S501: obtaining the voltage Vds at two ends of the switching tube and the gate-source voltage Vgs of the switching tube;
s502: judging whether Vds reaches the falling edge, if not, continuing to execute S502; if so, the judgment of S503-S505 is performed.
S503: when Vgs is greater than the preset voltage V1 and less than the threshold voltage vgs_gate, S506 is performed; the threshold voltage vgs_gate is the parameter of the controllable switching tube itself, which has been calibrated when the switching tube leaves the factory.
S504: when Vgs is greater than the threshold voltage vgs_gate, S508 is performed;
s505: when Vgs is smaller than the preset voltage V1, the controllable switching tube is controlled to work normally, and the LLC resonant converter operates normally.
S506: setting the switching frequency of the controllable switching tube as a preset frequency, wherein the preset frequency is the minimum allowable switching frequency.
S507: and judging whether the gain of the LLC resonant converter meets the requirement, for example, whether the gain is within a preset interval range, and if so, controlling the controllable switching tube to work normally, wherein the LLC resonant converter operates normally.
S508: and closing the driving, namely closing the wave, stopping driving a controllable switching tube in the LLC resonant converter to act, and stopping the LLC resonant converter from carrying out power conversion.
Power supply system embodiment
Based on the LLC resonant converter and the control method provided in the above embodiments, embodiments of the present application further provide a power supply system, which is described in detail below with reference to the accompanying drawings.
Referring to fig. 7, a schematic diagram of a power supply system according to an embodiment of the present application is shown.
The power supply system provided in this embodiment includes: a rectifying circuit 700 and an LLC resonant converter 800 described in the above embodiments;
the input end of the rectifying circuit 700 is used for being connected with alternating current; for example, the alternating current is AC220V.
An output terminal of the rectifying circuit 700 is connected to an input terminal of the LLC resonant converter 800.
The LLC resonant converter 800 is a DC-to-DC converter, the input is DC voltage, the output is also DC voltage, the DC voltage output by the LLC resonant converter 800 can be used for directly supplying power to a load, or can be used for supplying power to the load through a primary DC/DC circuit.
Because the power supply system provided by the embodiment of the application comprises the LLC resonant converter, and the switching tube in the LLC resonant converter can realize ZVS when in operation, thereby reducing power consumption, avoiding higher power consumption and higher temperature rise when not in operation in ZVS, and ensuring the safe operation of the whole power supply system.
From the above description of embodiments, it will be apparent to those skilled in the art that all or part of the steps of the above described example methods may be implemented in software plus necessary general purpose hardware platforms. Based on such understanding, the technical solution of the present application may be embodied essentially or in a part contributing to the prior art in the form of a software product, which may be stored in a storage medium, such as ROM/RAM, a magnetic disk, an optical disk, etc., including several instructions for causing a computer device (which may be a personal computer, a server, or a network communication device such as a media gateway, etc.) to execute the method described in the embodiments or some parts of the embodiments of the present application.
It should be noted that, in the present description, each embodiment is described in a progressive manner, and each embodiment is mainly described in a different manner from other embodiments, and identical and similar parts between the embodiments are all enough to refer to each other. For the method disclosed in the embodiment, since it corresponds to the system disclosed in the embodiment, the description is relatively simple, and the relevant points refer to the system part.
It should also be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.
The previous description of the disclosed embodiments, to enable any person skilled in the art to make or use the present application, will be readily apparent to those of ordinary skill in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (14)
1. An LLC resonant converter, comprising: at least one bridge arm, a capacitor, an inductor, a transformer and a controller; the at least one bridge arm comprises a controllable switch tube; the capacitor, the inductor and the primary winding of the transformer are connected in series to form an LLC resonant circuit;
the LLC resonant circuit is connected with the at least one bridge arm;
the controller is used for sealing the controllable switch tube when an intersection point exists between the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube, so that the LLC resonant circuit stops working; and when no intersection point exists between the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate source voltage of the controllable switch tube, controlling the controllable switch tube to work normally.
2. The LLC resonant converter of claim 1, wherein the controller is configured to seal the controllable switching tube when the gate-source voltage of the controllable switching tube is determined to be greater than the threshold voltage of the controllable switching tube at a falling edge of the voltage across the controllable switching tube.
3. The LLC resonant converter of claim 1, wherein the controller is specifically configured to control the controllable switching tube to operate normally when the gate-source voltage of the controllable switching tube is determined to be less than a preset voltage, which is less than a threshold voltage of the controllable switching tube, at a falling edge of the voltages at both ends of the controllable switching tube.
4. A LLC resonant converter according to any of claims 1-3, wherein the controller is further configured to control the switching frequency of the controllable switching tube to be a preset frequency, which is the minimum switching frequency allowed by the controllable switching tube, when the gate-source voltage of the controllable switching tube is determined to be greater than a preset voltage and less than a threshold voltage, at the falling edge of the voltage across the controllable switching tube; the preset voltage is smaller than the threshold voltage of the controllable switch tube.
5. The LLC resonant converter of claim 4 wherein the controller is further configured to determine that the gain of the LLC resonant converter is in a predetermined interval after controlling the switching frequency of the controllable switching tube to a predetermined frequency, and to control the controllable switching tube to operate normally, and vice versa.
6. A LLC resonant converter according to any of the claims 1-3, characterized in that the controller is also adapted to capture the falling edge of the voltage across the controllable switching tube.
7. A LLC resonant converter according to any of the claims 1-3, characterized in that the LLC resonant converter comprises three-phase half-bridge legs;
the controller is specifically configured to obtain voltages at two ends of the controllable switching tube of each bridge arm of the three-phase half-bridge, and seal all the controllable switching tubes of the three-phase half-bridge when a falling edge of the voltage at two ends of at least one controllable switching tube in the controllable switching tube of each bridge arm has an intersection point with a rising edge of a gate-source voltage of the controllable switching tube; and when no intersection point exists between the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube, controlling the controllable switch tube in the three-phase half-bridge arm to work normally.
8. A LLC resonant converter according to any of the claims 1-3, characterized in that the LLC resonant converter comprises single-phase half-bridge legs;
the controller is specifically configured to obtain voltages at two ends of the controllable switching tube of each bridge arm of the single-phase half-bridge, and seal all the controllable switching tubes of the single-phase half-bridge when a falling edge of the voltage at two ends of at least one controllable switching tube in the controllable switching tube of each bridge arm has an intersection point with a rising edge of a gate-source voltage of the controllable switching tube; and when no intersection point exists between the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube, controlling the controllable switch tube in the single-phase half-bridge arm to work normally.
9. A control method of an LLC resonant converter, wherein the LLC resonant converter includes at least one bridge arm, a capacitor, an inductor, a transformer, and a controller; the at least one bridge arm comprises a controllable switch tube; the capacitor, the inductor and the primary winding of the transformer are connected in series to form an LLC resonant circuit; the LLC resonant circuit is connected with the at least one bridge arm; the method comprises the following steps:
detecting the voltage at two ends of the controllable switch tube and the gate-source voltage of the controllable switch tube;
judging that the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube have an intersection point, and sealing the controllable switch tube to stop the LLC resonant circuit;
and when judging that the falling edge of the voltage at two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube have no intersection point, controlling the controllable switch tube to work normally.
10. The method according to claim 9, wherein determining that there is an intersection between a falling edge of the voltage across the controllable switching tube and a rising edge of the gate-source voltage of the controllable switching tube, specifically comprises:
and judging that an intersection point exists between the falling edge of the voltage at the two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube when the gate-source voltage of the controllable switch tube is larger than the threshold voltage of the controllable switch tube.
11. The method according to claim 9, wherein the determining that there is no intersection between the falling edge of the voltage across the controllable switching tube and the rising edge of the gate-source voltage of the controllable switching tube specifically includes:
judging that the gate-source voltage of the controllable switch tube is smaller than a preset voltage at the falling edge of the voltage at the two ends of the controllable switch tube, and judging that no intersection point exists between the falling edge of the voltage at the two ends of the controllable switch tube and the rising edge of the gate-source voltage of the controllable switch tube; the preset voltage is smaller than the threshold voltage of the controllable switch tube.
12. The method according to claim 10 or 11, further comprising: when the falling edge of the voltage at two ends of the controllable switch tube judges that the gate-source voltage of the controllable switch tube is larger than a preset voltage and smaller than the threshold voltage, the switching frequency of the controllable switch tube is controlled to be a preset frequency, and the preset frequency is the minimum switching frequency allowed by the controllable switch tube; the preset voltage is smaller than the threshold voltage of the controllable switch tube.
13. The method as recited in claim 12, further comprising: after the switching frequency of the controllable switching tube is controlled to be the preset frequency, judging that the gain of the LLC resonant converter is in a preset interval, controlling the controllable switching tube to normally operate, and otherwise, sealing the controllable switching tube.
14. A power supply system, comprising: a rectifying circuit and an LLC resonant converter as claimed in any one of claims 1 to 8;
the input end of the rectifying circuit is used for being connected with alternating current;
the output end of the rectifying circuit is connected with the input end of the LLC resonant converter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111349896.0A CN113922677B (en) | 2021-11-15 | 2021-11-15 | LLC resonant converter, method and power supply system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111349896.0A CN113922677B (en) | 2021-11-15 | 2021-11-15 | LLC resonant converter, method and power supply system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113922677A CN113922677A (en) | 2022-01-11 |
| CN113922677B true CN113922677B (en) | 2023-10-31 |
Family
ID=79246696
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111349896.0A Active CN113922677B (en) | 2021-11-15 | 2021-11-15 | LLC resonant converter, method and power supply system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113922677B (en) |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104065275A (en) * | 2014-06-16 | 2014-09-24 | 矽力杰半导体技术(杭州)有限公司 | Quasi-resonance control circuit and method for zero-voltage switching and flyback converter |
| CN104167948A (en) * | 2014-09-11 | 2014-11-26 | 上海理工大学 | Variable-frequency soft switching control method of micro photovoltaic grid-connected inverter |
| CN106329916A (en) * | 2016-08-29 | 2017-01-11 | 杰华特微电子（杭州）有限公司 | Driving method and circuit for switching tube and power system |
| KR20190072794A (en) * | 2017-12-18 | 2019-06-26 | 순천향대학교 산학협력단 | High Efficiency LLC Resonant Converter with Balanced Secondary Currents using the Two Transformer Structure |
| CN110071640A (en) * | 2019-04-01 | 2019-07-30 | 三峡大学 | A kind of three times stream rectification LLC three phase full bridge DC converter |
| CN110492724A (en) * | 2019-09-16 | 2019-11-22 | 安徽省东科半导体有限公司 | A kind of power tube drive circuit and driving method |
| CN111130514A (en) * | 2019-12-30 | 2020-05-08 | 华为技术有限公司 | Control method and control device for switching device |
| CN113270998A (en) * | 2021-07-06 | 2021-08-17 | 阳光电源股份有限公司 | Capacitive area protection method of LLC circuit and LLC resonant converter |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102013218228A1 (en) * | 2013-09-11 | 2015-03-12 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | DC-DC CONVERTER |
-
2021
- 2021-11-15 CN CN202111349896.0A patent/CN113922677B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104065275A (en) * | 2014-06-16 | 2014-09-24 | 矽力杰半导体技术(杭州)有限公司 | Quasi-resonance control circuit and method for zero-voltage switching and flyback converter |
| CN104167948A (en) * | 2014-09-11 | 2014-11-26 | 上海理工大学 | Variable-frequency soft switching control method of micro photovoltaic grid-connected inverter |
| CN106329916A (en) * | 2016-08-29 | 2017-01-11 | 杰华特微电子（杭州）有限公司 | Driving method and circuit for switching tube and power system |
| KR20190072794A (en) * | 2017-12-18 | 2019-06-26 | 순천향대학교 산학협력단 | High Efficiency LLC Resonant Converter with Balanced Secondary Currents using the Two Transformer Structure |
| CN110071640A (en) * | 2019-04-01 | 2019-07-30 | 三峡大学 | A kind of three times stream rectification LLC three phase full bridge DC converter |
| CN110492724A (en) * | 2019-09-16 | 2019-11-22 | 安徽省东科半导体有限公司 | A kind of power tube drive circuit and driving method |
| CN111130514A (en) * | 2019-12-30 | 2020-05-08 | 华为技术有限公司 | Control method and control device for switching device |
| CN113270998A (en) * | 2021-07-06 | 2021-08-17 | 阳光电源股份有限公司 | Capacitive area protection method of LLC circuit and LLC resonant converter |
Non-Patent Citations (2)
| Title |
|---|
| Investigation of an LLC resonant DC/DC converter with a capacitive output filter, Part II-Design Considerations;T. G. Grigorova, A. S. Vuchev and I. P. Maradzhiev;《2019 IEEE XXVIII International Scientific Conference Electronics (ET)》;pp. 1-4 * |
| 一种全桥LLC 谐振倍压变换器的电路特性分析;李建兵等;《信息工程大学学报》;第18卷(第5期);566-571 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113922677A (en) | 2022-01-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10069426B2 (en) | Active clamp flyback converter | |
| Kummari et al. | An isolated high-frequency link microinverter operated with secondary-side modulation for efficiency improvement | |
| CN105375783B (en) | The realization circuit of the control method and two methods of feedback and the asymmetrical half-bridge formula flyback converter based on this method | |
| CN103973092B (en) | A kind of soft-start method of LLC resonant converter | |
| TWI568166B (en) | A High Efficiency LLC Resonant Converter with Secondary Side Synchronous Rectifier Blind Control | |
| EP3346596B1 (en) | Symmetric time shift control for resonant converters | |
| US10461653B1 (en) | Active-clamp flyback circuit and control method thereof | |
| EP3565100A1 (en) | Llc resonant converter | |
| US10199949B1 (en) | Active-clamp flyback circuit and control method thereof | |
| US20180294735A1 (en) | Control device and control method | |
| JP5938008B2 (en) | Power converter | |
| CN101141095B (en) | Synchronous commutation consequent converter with reverse current suppresser | |
| CN104868767A (en) | Inverting Apparatus And Control Method Thereof | |
| CN104269999B (en) | The closed loop of controlled resonant converter starts method | |
| CN111585440B (en) | Control system and method of active clamp flyback converter | |
| EP4047805B1 (en) | Controller and control system for dc/dc converter | |
| TWI683513B (en) | Power converter and control method | |
| WO2022247531A1 (en) | Resonant conversion system and control method | |
| JP2002238257A (en) | Control method for resonance dc-dc converter | |
| US20220158536A1 (en) | Soft-start for resonant converters | |
| CN110380619B (en) | Direct current conversion circuit, control method thereof and direct current conversion device | |
| CN203911764U (en) | High light-load efficiency digital power supply suitable for server | |
| CN113922677B (en) | LLC resonant converter, method and power supply system | |
| JP5303869B2 (en) | DC-DC converter | |
| CN203574559U (en) | Asymmetrical half-bridge power converter with active power factor correction |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |