CN115149809A - Non-isolated full-bridge cascaded converter circuit and control method thereof - Google Patents
Non-isolated full-bridge cascaded converter circuit and control method thereof Download PDFInfo
- Publication number
- CN115149809A CN115149809A CN202210917144.8A CN202210917144A CN115149809A CN 115149809 A CN115149809 A CN 115149809A CN 202210917144 A CN202210917144 A CN 202210917144A CN 115149809 A CN115149809 A CN 115149809A
- Authority
- CN
- China
- Prior art keywords
- tube
- switching tube
- switching
- switch tube
- switch
- 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
- 238000000034 method Methods 0.000 title claims abstract description 8
- 238000004804 winding Methods 0.000 claims abstract description 119
- 239000003990 capacitor Substances 0.000 claims abstract description 17
- 230000009471 action Effects 0.000 claims description 8
- 230000000295 complement effect Effects 0.000 claims description 4
- 238000011161 development Methods 0.000 description 6
- 230000008878 coupling Effects 0.000 description 4
- 238000010168 coupling process Methods 0.000 description 4
- 238000005859 coupling reaction Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 238000001914 filtration Methods 0.000 description 3
- 230000006870 function Effects 0.000 description 3
- 238000002955 isolation Methods 0.000 description 3
- 230000009467 reduction Effects 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- 230000008859 change Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 230000009977 dual effect Effects 0.000 description 2
- 230000010363 phase shift Effects 0.000 description 2
- 230000009466 transformation Effects 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 230000005669 field effect Effects 0.000 description 1
- 230000001939 inductive effect Effects 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 230000015654 memory Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
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
- H02M3/02—Conversion of DC power input into DC power output without intermediate conversion into AC
- H02M3/04—Conversion of DC power input into DC power output without intermediate conversion into AC by static converters
- H02M3/10—Conversion of DC power input into DC power output without intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M3/145—Conversion of DC power input into DC power output without intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
- H02M3/155—Conversion of DC power input into DC power output without intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/156—Conversion of DC power input into DC power output without intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage or current, e.g. switching regulators
- H02M3/158—Conversion of DC power input into DC power output without intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage or current, e.g. switching regulators including plural semiconductor devices as final control devices for a single load
-
- 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
- H02M1/0048—Circuits or arrangements for reducing losses
- H02M1/0054—Transistor switching losses
- H02M1/0058—Transistor switching losses by employing soft switching techniques, i.e. commutation of transistors when applied voltage is zero or when current flow is zero
-
- 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
- H02M1/0067—Converter structures employing plural converter units, other than for parallel operation of the units on a single load
- H02M1/007—Plural converter units in cascade
-
- 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
- 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
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Dc-Dc Converters (AREA)
Abstract
The invention provides a non-isolated full-bridge cascade converter circuit and a control method thereof, wherein the circuit comprises: the power supply, the high-side switch bridge, the transformer, the rectifier bridge, the inductor, the capacitor and the load; the high-side switch bridge comprises a first switch tube, a second switch tube, a third switch tube and a fourth switch tube; the transformer comprises a first winding and a second winding; the rectifier bridge comprises a fifth switching tube, a sixth switching tube, a seventh switching tube and an eighth switching tube. The circuit greatly reduces the number of layers of the PCB of the switching power supply circuit, and effectively controls the cost.
Description
Technical Field
The invention relates to the field of switching power supply circuits, in particular to a non-isolated full-bridge cascaded converter circuit and a control method thereof.
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 48V into 12v through a DCDC (direct current to direct current) power supply, converts 12v into various voltages as low as 0.6V required by each chipset, and also directly converts 48V into a Central Processing Unit (CPU) core (core) voltage of about 1V to supply power to a CPU. Because each chipset in the server system needs low-voltage power supply as low as 0.6V and also has many 12V loads, such as fans and memories, the way of converting 48V to 12V and then converting 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 demand for energy conservation and consumption reduction is higher and higher, which makes the conversion from 48V to 12V with low cost and high efficiency 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 common solution in the current market is to continuously optimize the power supply of a module which is widely applied in the traditional communication field and is converted from 48V to 12V; isolated half-bridge or full-bridge hard switching schemes are mostly adopted by power supply head enterprises in the application; as the field of the server does not need to be isolated, enterprises launch 48V to 12V module power supplies of non-isolated versions in a dispute, namely, the ground of the original secondary side is directly connected, and isolation measures such as driving, sampling, insulation avoidance of the original secondary side and the like in an isolation scheme are cancelled so as to reduce cost and improve efficiency. In order to achieve higher efficiency and power density, the development direction continuously increases the layer number and copper thickness of a Printed Circuit Board (PCB), continuously optimizes the design of an isolation transformer, and selects a power field effect transistor with more excellent performance, which brings the consequences of continuously increasing the product cost, lengthening the development cycle, improving the design difficulty and the technical requirements for technicians, so that the development of the direction reaches a bottleneck, and the continuous balanced development between the performance and the price is difficult.
Disclosure of Invention
The invention provides a non-isolated full-bridge cascade converter circuit, which achieves the purposes of reducing the number of turns of a transformer and reducing the current effective values of a transformer winding and a rectifier switch device simultaneously after a full-bridge converter and an output rectifying circuit are cascaded, greatly reduces the number of PCB layers of a power supply scheme because the number of turns is reduced, effectively controls the cost and shortens the development cycle; meanwhile, the effective value of the current flowing through the transformer winding and the rectifying switch device is greatly reduced, so that the efficiency of the converter is greatly improved.
In a first aspect, the present invention provides a non-isolated full-bridge cascaded converter circuit, comprising: the power supply, the high-side switch bridge, the transformer, the rectifier bridge, the inductor, the capacitor and the load; wherein: the high-side switch bridge comprises a first switch tube, a second switch tube, a third switch tube and a fourth switch tube; the transformer comprises a first winding and a second winding; the rectifier bridge comprises a third switching tube, a sixth switching tube, a seventh switching tube and an eighth switching tube.
The high-side switch bridge is characterized in that first ends of a first switch tube and a second switch tube of the high-side switch bridge are connected with a positive power supply, a second end of the first switch tube and a first end of a third switch tube are connected with a different name end of a first winding, a second end of the second switch tube and a first end of a fourth switch tube are connected with a same name end of the first winding, a second end of the third switch tube and a second end of the fourth switch tube are connected with a first end of a fifth switch tube, a first end of a sixth switch tube and a first end of an inductor, a second end of the fifth switch tube and a first end of a seventh switch tube are connected with a same name end of the second winding, a second end of the sixth switch tube and a first end of an eighth switch tube are connected with a different name end of the second winding, a second end of the inductor is connected with a positive electrode of a capacitor and a positive electrode of a load, and a second end of the seventh switch tube, a second end of the eighth switch tube, a negative electrode of the power supply, a negative electrode of the capacitor and a negative electrode of the load are connected with a ground.
In a possible embodiment, it is assumed that the first winding and the second winding have n1 and n2 turns respectively; the circuit further comprises a controller coupled to the high-side switch bridge and the rectifier bridge, wherein the controller is used for controlling the first switch tube, the second switch tube, the third switch tube and the fourth switch tube to be switched on or off simultaneously, the second switch tube and the third switch tube are switched on or off simultaneously, the switching-on or switching-off time of the first switch tube, the fourth switch tube, the second switch tube and the third switch tube is equal, and the first winding and the second winding are connected in series and then bear pulse voltages with the amplitude value of power supply voltage and the width of conduction time of the first switch tube, the fourth switch tube, the second switch tube and the third switch tube, so that the platform voltage Vin/(n 1+ n 2) times the power supply voltage and the width of conduction time of the first switch tube, the fourth switch tube, the second switch tube and the third switch tube are generated at the first end of the inductor, and output voltage is generated through the filtering action of the inductor and the capacitor; the relation between the power supply and the output voltage satisfies the following conditions:
V 0 ＝2D×n2/(n1+n2)×Vin
wherein Vin represents a power voltage, vo represents an output voltage, and D is an on duty ratio of the first switching tube and the fourth switching tube or the second switching tube and the third switching tube.
In the above embodiment, the number of turns of the first winding N1 is reduced by N2 in comparison with the conventional full-bridge converter under the same voltage condition. When the first switch tube, the fourth switch tube or the second switch tube, the third switch tube are switched on, the first winding, the second winding are connected in series and then connected at the two ends of the power supply, the homonymy end of the first winding, the homonymy end of the second winding are connected with the heteronymy end, the homonymy end and the heteronymy end of the first winding, the second winding are connected with each other, the currents of the first winding and the second winding are simultaneously flowed out, the currents of the first winding and the second winding are equal to each other, and according to the turn relation of the transformer, the currents of the first winding and the currents of the second winding are satisfied:
I1×n1＝I2×n2；I Lf = I1+ I2, where I1 denotes the current in the first winding, I2 denotes the current in the second winding, I Lf Is the current of the inductor.
Compared with the traditional full-bridge converter, the effective value of the current flowing through the second winding, the fifth switching tube, the sixth switching tube, the seventh switching tube and the eighth switching tube is reduced by I1, namely the current flowing through the winding N1 is reduced.
Due to the reduction of the number of turns of the winding N1, the number of layers of the PCB of the converter circuit is reduced, and the cost and the development period are reduced; the reduction of the current effective value of second winding, fifth switch tube, sixth switch tube, seventh switch tube, eighth switch tube has shown the promotion efficiency.
In a second aspect, the present invention also provides a control method for a non-isolated full-bridge cascaded converter circuit, which can be applied to any one of the above first aspects, and the method includes: the switching-on or switching-off of the first switching tube, the second switching tube, the third switching tube and the fourth switching tube is controlled, so that the voltage of a power supply is applied to the first winding and the second winding which are connected in series, pulse voltage is generated at the connection point of the fifth switching tube, the sixth switching tube and the first end of the inductor, the pulse voltage generates output voltage through the filtering action of the inductor and the capacitor, and the output voltage supplies power to a load.
In summary, the invention provides a brand-new circuit topology, namely a non-isolated full-bridge cascaded converter, and after the traditional full-bridge converter is cascaded with an output rectifying circuit, the purposes of reducing the number of turns of a transformer and reducing the current effective values of a transformer winding and a switching device are achieved; meanwhile, the effective value of the current flowing through the transformer winding and the switching device is greatly reduced, so that the efficiency of the converter circuit is greatly improved, the working principle of the circuit is similar to that of the traditional full-bridge converter, but the circuit is simpler in structure, safe and reliable, and simple and easy to control.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a circuit topology diagram of a converter using MOS transistors as rectifier bridges according to an embodiment;
FIG. 2 is a main operating waveform of an embodiment of the present invention;
FIG. 3 is a circuit topology diagram of a converter employing diodes as rectifier bridges according to an embodiment;
FIG. 4 is a converter circuit topology showing the series capacitance of winding N1 of the converter circuit in one embodiment;
fig. 5 is a converter circuit topology diagram of the converter circuit according to the first embodiment, in which the winding N1 of the converter circuit is connected in series with an inductor or soft switching is realized by using the inductor.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments 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 derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example one
As shown in fig. 1, the present invention provides a non-isolated full-bridge cascaded converter circuit, which includes a power source Vin, a high-side switching bridge, a transformer Tx, a rectifier bridge and an inductor Lf, a capacitor Co and a load Ro; wherein:
the high-side switch bridge comprises a first switch tube S1, a second switch tube S2, a third switch tube S3 and a fourth switch tube S4; the transformer Tx includes a first winding N1 and a second winding N2; the rectifier bridge comprises a fifth switching tube S5, a sixth switching tube S6, a seventh switching tube S7 and an eighth switching tube S8.
A first end of a first switch tube S1 and a first end of a second switch tube S2 of the high-side switch bridge are both connected with the positive pole of a power source Vin, a second end of the first switch tube S1 and a first end of a third switch tube S3 are both connected with the different-name end of the first winding N1, a second end of the second switch tube S2 and a first end of a fourth switch tube S4 are both connected with the same-name end of the first winding N1, a second end of the third switch tube S3 and a second end of the fourth switch tube S4 are connected with a first end of a fifth switch tube S5, a first end of a sixth switch tube S6 and a first end of an inductor Lf, a second end of the fifth switch tube S5 and a first end of a seventh switch tube S7 are both connected with the same-name end of the second winding N2, a second end of the sixth switch tube S6 and a first end of an eighth switch tube S8 are both connected with the different-name end of the second winding N2, a second end of the inductor S7 and a negative pole of the inductor Ro, a negative pole of the load of the seventh switch tube S7, a negative pole of the load of the inductor Ro and a load.
In a possible embodiment, the first switching tube S1, the second switching tube S2, the third switching tube S3, and the fourth switching tube S4 in the high-side switching bridge may be any one or a combination of various controllable switching devices, such as a MOSFET, an IGBT, a GAN, a SiCMOS, and the like, which can perform a switching function.
It should be noted that, the numbers of turns of the first winding N1 and the second winding N2 are assumed herein to be N1 and N2 turns, respectively. For convenient analysis, neglecting the leakage inductance and the excitation inductance of the transformer, all the devices in the circuit are ideal devices.
As shown in fig. 2, the operation mode of the non-isolated full-bridge cascaded converter in each switching period is composed of 4 modes, which will be described below according to different operation modes.
Mode 0: before the time t0, the controller controls the first switch tube S1, the fourth switch tube S4, the sixth switch tube S6 and the seventh switch tube S7 to be turned on, and controls the second switch tube S2, the third switch tube S3, the fifth switch tube S5 and the eighth switch tube S8 to be turned off, at this time, the different-name end of the first winding N1 is connected with the positive electrode of the power Vin, the same-name end of the first winding N1 is connected with the different-name end of the second winding N2, and the same-name end of the second winding N2 is grounded, that is, the first winding N1 and the second winding N2 are connected in series and then connected in parallel with two ends of the power Vin, so that the voltage at the point C in fig. 1, that is, the voltage at the first end of the inductor Lf is the partial voltage of the first winding N1 and the voltage of the second winding N2 to the power Vin, and can be known according to the transformation ratio relationship of the transformer Tx, at this time, the voltage at the point C satisfies the following formula:
VC = n 2/(n 1+ n 2) × Vin, where Vin denotes a power supply voltage, VC is a voltage at point C, n1 is a first winding, and n2 is the number of turns of a second winding.
It can be seen that the inductor Lf current increases linearly under the combined action of the VC voltage and the output voltage Vo. Current I in inductor Lf Lf Equal to the first windingThe sum of the currents of the group N1 and the second winding N2; assuming that the current I1 of the first winding N1 and the current I2 of the second winding N2 are defined herein, the following formula is satisfied according to the coupling relationship of the transformer Tx:
I1×n1＝I2×n2
I Lf ＝I1+I2
wherein I1 represents the current in the first winding, I2 represents the current in the second winding, I Lf Is the current of the inductor.
Therefore, the winding N2 and the inductor Lf current satisfy the following formula:
I2＝I1×n1/n2
I Lf ＝I1×(n1+n2)/n2
wherein I1 represents the current in the first winding, I2 represents the current in the second winding, I Lf Is the current of the inductor.
Mode 1: at the time of t0, the first switching tube S1 and the fourth switching tube S4 are turned off, the sixth switching tube S6 and the seventh switching tube S7 are kept in an on state, the current of the first winding N1 is reduced to zero after losing a path, the current of the second winding N2 is also reduced to zero according to the coupling relationship of the transformer Tx, the current in the inductor Lf flows through the sixth switching tube S6, the seventh switching tube S7, the fifth switching tube S5 and the eighth switching tube S8 because the inductor current cannot suddenly change, the voltage at two ends of the second winding N2 is clamped to zero, the voltage at two ends of the first winding N1 is also zero, the fifth switching tube S5 and the eighth switching tube S8 are conducted at the time, the fifth switching tube S5 and the eighth switching tube S8 are turned on at the time, the VC voltage is zero, and the current of the inductor Lf is linearly reduced under the action of the output voltage Vo until the time of t 1. The sixth switching tube S6 and the seventh switching tube S7 are turned off before the time t1, and since the direction of the current in the inductor Lf is unchanged, the current flows through the sixth switching tube S6 and the seventh switching tube S7, and the operating state of the converter circuit is unchanged.
Mode 2: at the moment of t1, the second switching tube S2 and the third switching tube S3 are turned on, at this time, the dotted terminal of the first winding N1 is connected to the positive terminal of the power Vin, the dotted terminal of the first winding N1 is connected to the dotted terminal of the second winding N2, and the dotted terminal of the second winding N2 is grounded, that is, the first winding N1 and the second winding N2 are connected in series and then connected in parallel to the two terminals of the power Vin, so that the voltage at the point C, that is, the front end voltage of the inductor Lf, is the voltage division of the first winding N1 and the second winding N2 to the power Vin, and can be known according to the transformation ratio relationship of the transformer Tx, and at this time, the voltage VC at the point C satisfies the following formula:
VC＝n2/(n1+n2)×Vin
I Lf ＝I1+I2
thus, the inductor Lf current increases linearly under the combined action of the VC voltage and the output voltage Vo. Current I in inductance Lf Lf Equal to the current sum of the first winding N1 and the second winding N2; according to the coupling relation of the transformer Tx, the following conditions are satisfied:
I1×n1＝I2×n2
therefore, the second winding N2 and the inductor Lf satisfy:
I2＝I1×n1/n2
I Lf ＝I1×(n1+n2)/n2
it can be seen that the operating states of mode 0 are dual to mode 2.
Modality 3: at the time of t2, the second switching tube S2 and the third switching tube S3 are turned off, the fifth switching tube S5 and the eighth switching tube S8 are kept on, the current of the first winding N1 drops to zero after losing a path, the current of the second winding N2 also drops to zero according to the coupling relationship of the transformer Tx, since the inductive current cannot suddenly change, the current in the inductor Lf flows through the fifth switching tube S5, the eighth switching tube S8, the sixth switching tube S6 and the seventh switching tube S7, the voltage at both ends of the second winding N2 is clamped to zero, the voltage at both ends of the first winding N1 is also zero, since the sixth switching tube S6 and the seventh switching tube S7 are turned on at this time, the sixth switching tube S6 and the seventh switching tube S7 are turned on at zero voltage at this time, the VC voltage is zero, and the inductor Lf linearly drops the current under the action of the output voltage Vo until the time of t 1. Before the time t1, the fifth switching tube S5 and the eighth switching tube S8 are turned off, and the current direction of the inductor Lf is unchanged, so that the current flows through the fifth switching tube S5 and the eighth switching tube S8, and the operating state of the converter circuit is unchanged.
It can be seen that the modes 1 and 3 are dual in operation.
From the above analysis, the VC voltage is a pulse voltage with a certain width, and is converted into a stable output voltage Vo under the filtering action of the inductor Lf and the capacitor Co; vo satisfies the following formula:
V 0 ＝2D×n2/(n1+n2)×Vin
wherein Vin represents a power voltage, vo represents an output voltage, and D is an on duty ratio of the first switching tube and the fourth switching tube or the second switching tube and the third switching tube.
In this embodiment, as compared with the conventional full-bridge converter circuit, the number of windings of the first winding N1 is reduced by N2 turns under the same voltage condition; in addition, as compared with the conventional full-bridge converter circuit, under the same voltage condition, the current value in the winding of the second winding N2 and the rectifier bridge is reduced by I1, that is, the current of the first winding N1 is reduced.
Example two
As shown in fig. 3, in this embodiment, the converter circuit in the above embodiment is modified as follows: the transformer Tx includes three windings, and the rectifier bridge adopts two switching tubes, wherein:
the high-side switch bridge comprises a first switch tube S1, a second switch tube S2, a third switch tube S3 and a fourth switch tube S4; the transformer Tx includes a first winding N1, a second winding N2, and a third winding N3; the rectifier bridge comprises a seventh switching tube S7 and an eighth switching tube S8.
The first end of a first switch tube S1 and the first end of a second switch tube S2 of the high-side switch bridge are both connected with the positive electrode of a power supply Vin, the second end of the first switch tube S1 and the first end of a third switch tube S3 are both connected with the different-name end of a first winding N1, the second end of the second switch tube S2 and the first end of a fourth switch tube S4 are both connected with the same-name end of the first winding N1, the second end of the third switch tube S3 and the first end of a seventh switch tube S7 are both connected with the same-name end of the second winding N2, the second end of the fourth switch tube S4 and the first end of an eighth switch tube S8 are both connected with the different-name end of a third winding N3, the different-name end of the second winding N2 is connected with the same-name end of the third winding N3 and the first end of an inductor Lf, the second end of the inductor Lf is connected with the positive electrode of a capacitor Co and a load Ro, and the negative electrode of the seventh switch tube S7 and the power supply Ro, the negative electrode of the load Ro and the load Ro are connected with the capacitor Ro.
It should be understood that the operating principle of the controller in the second embodiment is substantially the same as that in the first embodiment, and a repeated description is omitted here.
From the above analysis, the present transducer has the following features:
a. the capacitor is connected with the first winding N1 in series, so that the magnetic bias of the transformer Tx can be effectively inhibited; b. through connecting an inductor in series with the first winding N1 or utilizing a transformer Tx leakage inductor and adopting phase shift control, namely, the first switch tube S1 and the third switch tube S3 are complementarily conducted, the second switch tube S2 and the fourth switch tube S4 are complementarily conducted, and the first switch tube S1 and the third switch tube S3 are phase shift controlled with the second switch tube S2 and the fourth switch tube S4, zero voltage switching of the first switch tube S1, the second switch tube S2, the third switch tube S3 and the fourth switch tube S4 can be realized; c. through connecting an inductor in series with the first winding N1 or utilizing a transformer Tx leakage inductor, and adopting complementary conduction of the first switching tube S1 and the third switching tube S3, chopping work of the second switching tube S2 and the fourth switching tube S4, or complementary conduction of the second switching tube S2 and the fourth switching tube S4, and chopping work of the first switching tube S1 and the third switching tube S3, zero-voltage switching of the first switching tube S1, the second switching tube S2, the third switching tube S3 and the fourth switching tube S4 can be realized.
In a possible implementation manner, any one or a combination of multiple uncontrollable switching devices, such as a diode and a switching device capable of realizing a freewheeling function, or a combination of a diode and a switching device, such as a MOSFET, an IGBT, a GAN, a SiC MOS, and the like, may be used as the fifth switching tube S5, the sixth switching tube S6, the seventh switching tube S7, and the eighth switching tube S8 of the rectifier bridge in the first embodiment. For example, as shown in fig. 3, diodes may be used for the fifth switching tube S5, the sixth switching tube S6, the seventh switching tube S7, and the eighth switching tube S8.
In a possible implementation manner, this embodiment may further include a series impedance network for the first winding branch in the non-isolated full-bridge cascaded converter circuit shown in fig. 1 or fig. 3. Illustratively, the first winding branch may be connected in series with a capacitor C1 in the non-isolated full-bridge cascaded converter circuit shown in fig. 1, as shown in fig. 4, or the first winding branch may be connected in series with an inductor L1 in the non-isolated full-bridge cascaded converter circuit shown in fig. 1, as shown in fig. 5. It should be understood that the present invention may also be implemented in the non-isolated full-bridge cascaded converter circuit shown in fig. 3, in which the first winding branch is connected in series with a capacitor C1 or an inductor L1, which is not illustrated by way of example.
In a possible embodiment, the first switching tube S1, the second switching tube S2, the third switching tube S3, and the fourth switching tube S4 in the high-side switching bridge may be any one or a combination of various controllable switching devices, such as a MOSFET, an IGBT, a GAN, a SiC MOS, and the like, which can perform a switching function.
It should be understood that in the first embodiment, any one or combination of a plurality of controllable switching devices, such as a MOSFET, an IGBT, a GAN, a SiC MOS, etc., can be used for the fifth switching tube S5, the sixth switching tube S6, the seventh switching tube S7, and the eighth switching tube S8 of the rectifier bridge.
The above description is only a specific implementation of the embodiments of the present invention, but the scope of the embodiments of the present invention is not limited thereto, and any changes or substitutions within the technical scope disclosed by the embodiments of the present invention should be covered within the scope of the embodiments of the present invention. Therefore, the protection scope of the embodiments of the present invention shall be subject to the protection scope of the claims.
Claims (11)
1. A non-isolated full-bridge cascaded converter circuit, comprising: the power supply, the high-side switch bridge, the transformer, the rectifier bridge, the inductor, the capacitor and the load; wherein:
the high-side switch bridge comprises a first switch tube, a second switch tube, a third switch tube and a fourth switch tube;
the transformer comprises a first winding and a second winding;
the rectifier bridge comprises a fifth switching tube, a sixth switching tube, a seventh switching tube and an eighth switching tube;
the first end of the first switch tube and the first end of the second switch tube are connected with the positive electrode of the power supply, the second end of the first switch tube and the first end of the third switch tube are connected with the different name end of the first winding, the second end of the second switch tube and the first end of the fourth switch tube are connected with the same name end of the first winding, the second end of the third switch tube and the second end of the fourth switch tube are connected with the first end of the fifth switch tube, the first end of the sixth switch tube and the first end of the inductor after being connected, the second end of the fifth switch tube and the first end of the seventh switch tube are connected with the same name end of the second winding, the second end of the sixth switch tube and the first end of the eighth switch tube are connected with the different name end of the second winding, the second end of the inductor is connected with the positive electrode of the capacitor and the positive electrode of the load, and the second end of the eighth switch tube, the negative electrode of the power supply, the negative electrode of the capacitor and the negative electrode of the load are connected with the ground.
2. The circuit of claim 1, further comprising a controller coupled to the high-side switching bridge and the rectifier bridge, wherein the controller is configured to control the first switching tube, the second switching tube, the third switching tube, and the fourth switching tube to be turned on or off, so that the voltage of the power supply is applied to the first winding and the second winding connected in series, and a pulse voltage is generated at a connection point of the fifth switching tube, the sixth switching tube, and the first end of the inductor, and the pulse voltage is filtered by the inductor and the capacitor to generate an output voltage, and the output voltage supplies power to the load.
3. The circuit of claim 2, wherein the controller is further configured to control the first switching tube and the fourth switching tube to be turned on or off simultaneously, and the second switching tube and the third switching tube to be turned on or off simultaneously, and the turn-on or turn-off time of the first switching tube and the turn-off time of the fourth switching tube is equal to that of the second switching tube and the third switching tube.
4. The circuit of claim 2 or 3, wherein the controller is further configured to:
the duty ratio of the first switch tube and the third switch tube is controlled to be in complementary conduction of 50%, the duty ratio of the second switch tube and the fourth switch tube is controlled to be in complementary conduction of 50%, the first switch tube and the third switch tube are in phase-shifting control with the second switch tube and the fourth switch tube to adjust output voltage, and meanwhile, zero-voltage switching of the first switch tube, the second switch tube, the third switch tube and the fourth switch tube can be achieved by utilizing the first winding series inductance or the transformer leakage inductance.
5. The circuit of claim 2 or 3, wherein the controller is further configured to: the first switch tube and the third switch tube are controlled to be conducted complementarily, the second switch tube and the fourth switch tube are controlled to be conducted complementarily, the output voltage is adjusted by adjusting the duty ratio of the first switch tube and the third switch tube and the duty ratio of the second switch tube and the fourth switch tube, and zero-voltage switching of the first switch tube, the second switch tube, the third switch tube and the fourth switch tube can be realized by utilizing the first winding series inductance or the transformer leakage inductance.
6. A circuit according to any one of claims 1 to 3, further comprising an impedance network in series with the first winding branch.
7. The circuit according to any one of claims 1 to 3, wherein the first switching tube, the second switching tube, the third switching tube and the fourth switching tube in the high-side switching bridge adopt any one or combination of a plurality of controllable switching devices capable of realizing switching action.
8. The circuit according to any one of claims 1 to 3, wherein the fifth switching tube, the sixth switching tube, the seventh switching tube and the eighth switching tube in the rectifier bridge adopt any one or a combination of a plurality of uncontrollable switching devices capable of realizing a rectification function.
9. The circuit according to any one of claims 1 to 3, wherein the fifth switching tube, the sixth switching tube, the seventh switching tube and the eighth switching tube in the rectifier bridge adopt any one or combination of a plurality of controllable or uncontrollable switching devices capable of realizing a rectification function.
10. A control method for a non-isolated full-bridge cascaded converter circuit applied to the non-isolated full-bridge cascaded converter circuit according to any one of claims 1 to 9, comprising:
before the time t0, controlling the first switching tube, the fourth switching tube, the sixth switching tube and the seventh switching tube to be switched on, and controlling the second switching tube, the third switching tube, the fifth switching tube and the eighth switching tube to be switched off;
at the time of t0, the first switching tube and the fourth switching tube are turned off, and the sixth switching tube and the seventh switching tube S7 are kept in an on state;
at the moment of t1, a second switching tube and a third switching tube are switched on;
and at the time of t2, the second switching tube and the third switching tube are turned off, the fifth switching tube and the eighth switching tube are kept on, so that the current in the inductor flows through the fifth switching tube, the eighth switching tube, the sixth switching tube and the seventh switching tube, and the voltages at the two ends of the second winding and the first winding are clamped at zero.
11. The method of claim 10, further comprising:
the time for controlling the first switch and the fourth switch tube to be simultaneously switched on or off and the time for controlling the second switch tube and the third switch tube to be simultaneously switched on or off are equal.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210917144.8A CN115149809A (en) | 2022-08-01 | 2022-08-01 | Non-isolated full-bridge cascaded converter circuit and control method thereof |
| PCT/CN2023/102030 WO2024027360A1 (en) | 2022-08-01 | 2023-06-25 | Non-isolated full-bridge cascade converter circuit and control method therefor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210917144.8A CN115149809A (en) | 2022-08-01 | 2022-08-01 | Non-isolated full-bridge cascaded converter circuit and control method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115149809A true CN115149809A (en) | 2022-10-04 |
Family
ID=83414039
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210917144.8A Pending CN115149809A (en) | 2022-08-01 | 2022-08-01 | Non-isolated full-bridge cascaded converter circuit and control method thereof |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN115149809A (en) |
| WO (1) | WO2024027360A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2024027360A1 (en) * | 2022-08-01 | 2024-02-08 | 上海英联电子系统有限公司 | Non-isolated full-bridge cascade converter circuit and control method therefor |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7110265B2 (en) * | 2002-12-09 | 2006-09-19 | Queen's University At Kingston | Non-isolated DC-DC converters with direct primary to load current |
| CN100346562C (en) * | 2004-01-19 | 2007-10-31 | 南京航空航天大学 | Transformer clamping zero voltage switch three level full bridge converter and its expansion circuit |
| CN205911954U (en) * | 2016-06-19 | 2017-01-25 | 江苏爱克赛电气制造有限公司 | Soft switch electrical energy conversion series connected output device of looks full -bridge is moved to high efficiency |
| CN206517302U (en) * | 2017-03-07 | 2017-09-22 | 深圳麦格米特电气股份有限公司 | A kind of circuit of the resonator clamp of the Sofe Switch DC converter of plus clamp diode device |
| CN113131742B (en) * | 2021-03-09 | 2022-04-15 | 广州金升阳科技有限公司 | Wide voltage input four-tube Buck-Boost circuit |
| CN115149809A (en) * | 2022-08-01 | 2022-10-04 | 上海英联电子系统有限公司 | Non-isolated full-bridge cascaded converter circuit and control method thereof |
-
2022
- 2022-08-01 CN CN202210917144.8A patent/CN115149809A/en active Pending
-
2023
- 2023-06-25 WO PCT/CN2023/102030 patent/WO2024027360A1/en unknown
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2024027360A1 (en) * | 2022-08-01 | 2024-02-08 | 上海英联电子系统有限公司 | Non-isolated full-bridge cascade converter circuit and control method therefor |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2024027360A1 (en) | 2024-02-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106059313B (en) | The circuit of reversed excitation and its control method of active clamp | |
| US6246599B1 (en) | Constant frequency resonant inverters with a pair of resonant inductors | |
| CN101686015B (en) | Forward-Flyback Converter with Active Clamp | |
| Chung et al. | A zero-current-switching PWM flyback converter with a simple auxiliary switch | |
| CN105896986B (en) | A kind of controlled resonant converter and its control method | |
| US20100328971A1 (en) | Boundary mode coupled inductor boost power converter | |
| CN110707931A (en) | LLC resonant converter and control method | |
| Ghodke et al. | Three-phase three level, soft switched, phase shifted PWM DC–DC converter for high power applications | |
| CN111478612B (en) | Phase-correlated voltage-regulator tube clamped auxiliary resonance converter pole inverter | |
| CN111525809B (en) | High-frequency hybrid direct-current converter with adjustable output voltage | |
| Hsieh et al. | A soft-switching interleaved buck–boost LED driver with coupled inductor | |
| US11539285B2 (en) | DC-to-DC converter | |
| CN112087143B (en) | Quasi-parallel resonant converter with multi-end input and single-end output | |
| US20230155510A1 (en) | Switching power supply circuit | |
| Shiva et al. | Tap changing transformer based dual active bridge bi-directional DC-DC converter | |
| CN209930559U (en) | LLC resonant converter and LED drive circuit | |
| CN114938144A (en) | Non-isolated LLC resonant converter circuit | |
| CN115149809A (en) | Non-isolated full-bridge cascaded converter circuit and control method thereof | |
| WO2024045798A1 (en) | Non-isolated llc resonant converter | |
| WO2024045797A1 (en) | Non-isolated resonant converter | |
| TWI501527B (en) | High voltage ratio interleaved converter with soft-switching using single auxiliary switch | |
| Li et al. | An efficiency-oriented two-stage structure employing partial power regulation | |
| Mao et al. | A new duty-cycle-shifted PWM control scheme for half-bridge DC-DC converters to achieve zero-voltage-switching | |
| CN110445392B (en) | Staggered parallel double-tube forward converter and modulation strategy thereof | |
| CN209982343U (en) | A circuit structure for realizing wide-gain FB-HB LLC resonant 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 |