A full-bridge converter based on adaptive current reset rectifier circuit

Abstract

The present invention discloses a full-bridge converter based on an adaptive current reset rectifier circuit, comprising an inverter circuit, a transformer circuit and an adaptive current reset rectifier circuit connected in sequence; the inverter circuit comprises a full-bridge inverter unit and an input power supply for powering the full-bridge inverter unit, which is used to provide an inverter signal for the transformer circuit; the transformer circuit comprises a transformer with a center tap, the primary side of the transformer is connected to the bridge arm of the full-bridge inverter unit, and the secondary side of the transformer is connected to the adaptive current reset rectifier circuit; the adaptive current reset rectifier circuit is used to provide an output voltage after the reset capacitor and the diode are commutated. The present invention uses the reset capacitor of the secondary side of the transformer to quickly reset the primary current of the full-bridge converter to a very small value during the freewheeling period, which greatly reduces the conduction loss of the freewheeling of the full-bridge converter.

Description

Technical Field

[0001] The invention relates to the technical field of power electronic devices, and in particular to a full-bridge converter based on an adaptive current reset rectifier circuit. Background Art

[0002] The full-bridge converter is widely used in high-power applications due to its simple structure, fewer components required, easy soft switching, and high efficiency. However, the full-bridge converter has fundamental disadvantages. The first disadvantage is that the conduction loss of the circulating current during the freewheeling period is significant. The second disadvantage is that there is a serious voltage overshoot on the secondary side rectifier diode. In order to reduce the voltage stress, an RCD snubber circuit is usually used. However, it will cause considerable losses in the snubber resistor. The third disadvantage is that a large output inductor L is required. O In a full-bridge converter, a large L is required. O To reduce the ripple current, which reduces the power density and increases the cost. In addition, since the soft switching of the main switch tube of the traditional full-bridge converter depends on the load size, when the load is very light, the energy stored in the primary leakage inductance is often unable to complete the charge and discharge of the junction capacitance of the lagging bridge arm switch tube, and the soft switching fails. Summary of the invention

[0003] Technical purpose: In view of the defects of the full-bridge converter in the prior art, the present invention discloses a full-bridge converter based on an adaptive current reset rectifier circuit. Through the reset capacitor on the secondary side of the transformer, the primary current of the full-bridge converter is quickly reset to a very small value during the freewheeling period, which greatly reduces the conduction loss of the full-bridge converter during the freewheeling period.

[0004] Technical solution: In order to achieve the above technical objectives, the present invention adopts the following technical solution.

[0005] A full-bridge converter based on an adaptive current reset rectifier circuit comprises an inverter circuit, a transformer circuit and an adaptive current reset rectifier circuit connected in sequence;

[0006] The inverter circuit includes a full-bridge inverter unit and an input power supply for supplying power to the full-bridge inverter unit, and is used to provide an inverter signal for the transformer circuit;

[0007] The transformer circuit includes a transformer with a center tap, the primary side of the transformer is connected to the bridge arm of the full-bridge inverter unit, and the secondary side of the transformer is connected to the adaptive current reset rectifier circuit, which is used to provide energy to the load of the secondary side and the reset capacitor Cr;

[0008] The adaptive current reset rectifier circuit is used to provide an output voltage after phase switching through a reset capacitor and a diode.

[0009] Preferably, the inverter circuit comprises an advanced bridge arm, a lagging bridge arm, an input power supply, an advanced bridge arm, and a lagging bridge arm trench full-bridge inverter unit; the advanced bridge arm comprises a first power switch tube Q1, a second power switch tube Q 2 The lagging bridge arm includes a third power switch tube Q3 and a fourth power switch tube Q4; the positive electrode of the input power supply is connected to the drain of the first power switch tube Q1 and the drain of the third power switch tube Q3, the source of the first power switch tube Q1 is connected to the drain of the second power switch tube Q2, and the midpoint thereof is used as the midpoint of the leading bridge arm; the source of the third power switch tube Q3 is connected to the drain of the fourth power switch tube Q4, and the midpoint thereof is used as the midpoint of the lagging bridge arm; the negative electrode of the input power supply is connected to the source of the second power switch tube Q2 and the source of the fourth power switch tube Q4; the midpoint of the leading bridge arm and the midpoint of the lagging bridge arm are used as the positive output terminal and the negative output terminal of the inverter circuit respectively.

[0010] Preferably, the transformer circuit comprises a transformer with a center tap; the same-name end of the primary side of the transformer is connected via a leakage inductance L r The positive output terminal of the inverter circuit is connected, the opposite-name terminal of the transformer primary side is connected to the negative output terminal of the inverter circuit, and the same-name terminal of the transformer primary side is connected to the positive output terminal of the inverter circuit through the excitation inductor L m The transformer is connected to the opposite-name terminal of the primary side of the transformer, the secondary side of the transformer includes a center tap, and the same-name terminal, the opposite-name terminal and the center tap of the secondary side of the transformer are all connected to the adaptive current reset rectifier circuit.

[0011] Preferably, the transformation ratio of the transformer is n:1:1, where n represents the transformation ratio coefficient; the center tap of the secondary side of the transformer is both the opposite-name end of the upper winding and the same-name end of the lower winding.

[0012] Preferably, the adaptive current reset rectifier circuit comprises a first rectifier diode D 1 , the second rectifier diode D 2 , the first filter inductor L 1 , the second filter inductor L 2 , reset capacitor Cr, output capacitor C o , load R; parallel output capacitor C o One end of the load R is connected to the load R through the first filter inductor L 1 With the first rectifier diode D 1 The negative terminal is connected in parallel with the output capacitor C o The other end of the load R is connected to the first rectifier diode D 1 The positive terminal of the parallel output capacitor C o One end of the load R is connected to the second filter inductor L 2 With the second rectifier diode D 2 The negative terminal is connected in parallel with the output capacitor C o The other end of the load R is connected to the second rectifier diode D2 The positive terminal of the first rectifier diode D 1 The negative terminal of the transformer is connected to the same terminal of the secondary side of the transformer in the transformer circuit, and the second rectifier diode D 2 The negative terminal of the transformer is connected to the opposite end of the secondary side of the transformer in the transformer circuit, and the second rectifier diode D 2 The positive terminal of the reset capacitor C r Connect to the center tap of the transformer in the transformer circuit.

[0013] Preferably, the first filter inductor L 1 , the second filter inductor L 2 The sense values ​​are equal.

[0014] Preferably, the first filter inductor L 1 , the second filter inductor L 2 The calculation formula of the inductance value includes:

[0015]

[0016] Among them, V o represents the output voltage, D represents the phase shift duty cycle, f represents the switching frequency, Indicates the ripple factor of the output filter inductor current.

[0017] Preferably, the reset capacitor C r The capacitance value is relatively large, and its calculation formula includes:

[0018]

[0019] Where n is the transformer turns ratio, D is the phase shift duty cycle, I is the output current, f is the switching frequency, V in Indicates the input voltage, Indicates the ripple factor of the reset capacitor voltage.

[0020] Beneficial effects:

[0021] (1) The present invention proposes a full-bridge converter based on an adaptive current reset rectifier circuit, which uses a reset capacitor on the secondary side of the transformer to quickly reset the primary current of the full-bridge converter to a very small value during the freewheeling period, thereby greatly reducing the conduction loss of the full-bridge converter during the freewheeling period.

[0022] (2) Due to the reset capacitor of the current reset rectifier circuit, the secondary rectifier diode does not rise to V at the moment of shutting off. i n / n, but rises to the voltage value V of the reset capacitor i n / 2n, where V i n is the voltage of the input power supply, and n is the transformation ratio coefficient, thereby reducing the reverse recovery loss and voltage overshoot of the secondary diode.

[0023] (3) When the full-bridge converter based on the adaptive current reset rectifier circuit proposed by the present invention commutates the lagging bridge arm, the output filter inductor and the transformer excitation inductor jointly charge and discharge the switch tube junction capacitance, so zero voltage switching can be easily achieved in the full load range.

[0024] (4) There is no stage where the rectifier diodes are turned on at the same time, that is, there is no duty cycle loss. This breaks the limitation that the traditional full-bridge converter cannot be applied to ultra-high frequencies due to duty cycle loss, and is of great significance to improving the switching frequency and power density of the full-bridge converter. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A topological structure diagram of a full-bridge converter based on an adaptive current reset rectifier circuit of the present invention;

[0026] Figures 2 to 11 The topological mode diagram of the full-bridge converter based on the adaptive current reset rectifier circuit of the present invention.

[0027] Fig.12 It is a principle waveform diagram of a full-bridge converter circuit based on an adaptive current reset rectifier circuit of the present invention; DETAILED DESCRIPTION

[0028] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0029] As attached Figure 1 As shown, a full-bridge converter based on an adaptive current reset rectifier circuit comprises an inverter circuit, a transformer circuit and an adaptive current reset rectifier circuit connected in sequence;

[0030] The inverter circuit includes a full-bridge inverter unit and an input power supply for supplying power to the full-bridge inverter unit, and is used to provide an inverter signal for the transformer circuit;

[0031] The transformer circuit includes a transformer with a center tap, the primary side of the transformer is connected to the bridge arm of the full-bridge inverter unit, and the secondary side of the transformer is connected to the adaptive current reset rectifier circuit, which is used to provide energy to the load of the secondary side and the reset capacitor Cr;

[0032] The adaptive current reset rectifier circuit is used to provide an output voltage after phase switching through a reset capacitor and a diode.

[0033] The inverter circuit includes an advanced bridge arm, a lagging bridge arm, an input power supply, an advanced bridge arm, and a lagging bridge arm trench full-bridge inverter unit; the advanced bridge arm includes a first power switch tube Q 1 , the second power switch tube Q 2 The lagging bridge arm includes the third power switch tube Q 3 , the fourth power switch tube Q 4 ; The positive electrode of the input power supply is connected to the drain of the first power switch tube Q1 and the drain of the third power switch tube Q 3 The drain of the first power switch tube Q 1 The source of the second power switch tube Q 2 The drain of is connected, and the midpoint is used as the midpoint of the leading bridge arm. The third power switch tube Q 3 The source and the fourth power switch tube Q 4 The drain of is connected, the midpoint of which is used as the midpoint of the lagging bridge arm, the negative electrode of the input power supply and the second power switch tube Q 2 The source of the fourth power switch tube Q 4 The midpoint of the leading bridge arm and the midpoint of the lagging bridge arm serve as the positive output terminal and the negative output terminal of the inverter circuit respectively.

[0034] The transformer circuit includes a transformer with a center tap; the same-name end of the primary side of the transformer is connected to the positive output end of the inverter circuit, that is, the midpoint of the leading bridge arm, through the leakage inductance Lr, and the opposite-name end of the primary side of the transformer is connected to the negative output end of the inverter circuit, that is, the midpoint of the lagging bridge arm, and the same-name end of the primary side of the transformer is connected to the negative output end of the inverter circuit, that is, the midpoint of the lagging bridge arm, through the excitation inductance Lr. m The transformer is connected to the opposite-name terminal of the primary side of the transformer, the secondary side of the transformer includes a center tap, and the same-name terminal, the opposite-name terminal and the center tap of the secondary side of the transformer are all connected to the adaptive current reset rectifier circuit;

[0035] Among them, the transformation ratio of the transformer is n:1:1, n represents the transformation ratio coefficient; n corresponds to the primary side of the transformer, and 1:1 corresponds to the secondary side of the transformer with a center tap; the center tap of the secondary side of the transformer is both the opposite end of the upper winding and the same end of the lower winding.

[0036] The adaptive current reset rectifier circuit includes a first rectifier diode D 1 , the second rectifier diode D 2 , the first filter inductor L 1 , the second filter inductor L 2 , reset capacitor Cr, output capacitor C o , load R; parallel output capacitor C o One end of the load R is connected to the load R through the first filter inductor L 1 With the first rectifier diode D 1 The negative terminal is connected in parallel with the output capacitor C o The other end of the load R is connected to the first rectifier diode D1 The positive terminal of the parallel output capacitor C o One end of the load R is connected to the second filter inductor L 2 With the second rectifier diode D 2 The negative terminal is connected in parallel with the output capacitor C o The other end of the load R is connected to the second rectifier diode D 2 The positive terminal of the first rectifier diode D 1 The negative terminal of the transformer is connected to the same terminal of the secondary side of the transformer in the transformer circuit, and the second rectifier diode D 2 The negative terminal of the transformer is connected to the opposite end of the secondary side of the transformer in the transformer circuit, and the second rectifier diode D 2 The positive terminal is connected to the center tap of the transformer in the transformer circuit through the reset capacitor Cr;

[0037] Among them, the reset capacitor C r The capacitance value is large, so that it can be regarded as a voltage source when the circuit is running stably. In actual design, the input voltage fluctuation can be calculated based on less than 10%. The first filter inductor L 1 , the second filter inductor L 2 The inductance values ​​are equal. Among them, the reset capacitor Cr and the output filter inductor L 1 , L 2 The calculation can refer to the following formula:

[0038]

[0039]

[0040] Where n is the transformer turns ratio, D is the phase shift duty cycle, and I o represents the output current, f represents the switching frequency, V in Indicates the input voltage, and They represent the ripple coefficients of the reset capacitor voltage and the output filter inductor current, which can generally be 10%. o Represents the output voltage, that is, the parallel output capacitor C o and the voltage across the load R.

[0041] The adaptive current reset rectifier circuit of the present invention utilizes a reset capacitor and diode commutation to reset the current during the freewheeling period of the full-bridge converter to a fixed very small value under any load condition, thereby solving the problem of large conduction losses during the freewheeling period of the traditional full-bridge converter. The junction capacitance charging and discharging energy of the four power switch tubes on the primary side is provided by the filter inductor and the excitation inductor on the secondary side, so that the full-bridge converter can easily achieve soft switching within the full load range. The secondary diode of the rectifier circuit of the present invention completes commutation during the primary freewheeling stage, which fundamentally solves the problem of duty cycle loss. The turn-off voltage of the secondary diode is much smaller than that of the traditional full-bridge converter rectifier circuit, which greatly reduces the reverse recovery loss. The proposed adaptive current reset rectifier circuit has a simple structure and low cost, and only includes a transformer with a center tap, a reset capacitor C r , two filter inductors L 1 , L 2 , two rectifier diodes D 1 , D 2 and an output capacitor C o , has high practical value.

[0042] As attached Fig.12 As shown in the figure, each switching cycle T of the full-bridge converter based on the adaptive current reset rectifier circuit of the present invention consists of two symmetrical half cycles. Figure 2 -Attached Fig.11 The working modes of the system are introduced.

[0043] Mode 1: If Figure 2 As shown, the first power switch tube Q1 and the fourth power switch tube Q4 in the full-bridge converter are turned on. r The capacitance of the reset capacitor C r The voltage across the two ends is V Cr Basically unchanged, so that the transformer primary voltage is clamped to nV Cr , leakage inductance L r The current increases rapidly at the difference between the input voltage and the transformer primary voltage. At this time, the second rectifier diode D2 on the transformer secondary side is turned on, and the full-bridge converter supplies the reset capacitor C r The first filter inductor L 1 The current flows through the load R and then flows through the second rectifier diode D 2 and two secondary windings of the transformer; the second filter inductor L 2 The current flows through the load R and the second rectifier diode D 2 .

[0044] Mode 2: If Figure 3As shown, the first power switch tube Q1 is turned off and the second power switch tube Q2 is turned on. Since the primary current is very large at this time, there is enough energy to charge and discharge the switch tube junction capacitance, so that the second power switch tube Q2 is turned on with zero voltage. Since the secondary current has not completed the phase change when the second power switch tube Q2 is just turned on, that is, the second rectifier diode D2 is still turned on, the primary voltage of the transformer remains nV Cr At this time, the transformer primary leakage current is nV Cr The first filter inductor L at the secondary side decreases rapidly. 1 , the second filter inductor L 2 The current gradually flows from the second rectifier diode D 2 Transfer to the reset capacitor Cr. Until the primary current I p Reduced to the excitation current I m The primary component (I L1 -I L2 ) / n are consistent, that is, I p =I m +(I L1 -I L2 ) / n, all diodes in the secondary rectifier are turned off. After turning off, the voltage of the diodes at the secondary side is equal to the voltage of the reset capacitor V Cr .

[0045] Mode 3: If Figure 4 As shown, at this time, the second power switch tube Q2 and the fourth power switch tube Q4 on the primary side are turned on, and the two rectifier diodes on the secondary side are both in the cut-off state. 1 , the second filter inductor L 2 After the current flows through the load and reset capacitor, it is shunted from the secondary center tap of the transformer. Since the turns ratio of the upper and lower windings of the secondary center tap is equal, the refracted primary current at this time is (I L1 -I L2 ) / n. At this time, the current on the primary side and the reset capacitor on the secondary side provide energy to the load. Since the voltages across the two filter inductors are the same, they are both the output voltage minus the reset capacitor voltage V o -V Cr , where V o Indicates the output voltage. That is, the current changes of the two are consistent. And the primary voltage of this transformer is 0, so that the primary current of the full-bridge converter basically maintains I p =I m +(I L1 -I L2 ) / n remains unchanged. And the secondary side L 1 , L 2 The inductance values ​​are equal and larger, so I p =I m +(I L1-I L2 ) / n is generally very small, which greatly reduces the conduction loss during the freewheeling period.

[0046] Mode 4: If Figure 5 As shown, at this time, the fourth power switch tube Q4 is turned off and the third power switch tube Q3 is turned on. Since the two diodes on the secondary side remain turned off during the commutation period, the excitation inductance and the output filter inductance act together on the primary side to charge and discharge the junction capacitance of the Q3 and Q4 switch tubes, so Q3 can easily achieve zero-current switching under a very small primary current. During the commutation process of the switch tubes Q3 and Q4, the voltage on the primary side of the transformer gradually increases, with the direction being positive at the bottom and negative at the top.

[0047] Mode 5: If Figure 6 As shown, during the commutation process of the third power switch tube Q3 and the fourth power switch tube Q4, the voltage on the primary side of the transformer gradually increases. When it increases to nV C When r, the secondary diode D 1 The secondary current also begins to gradually switch phases, and the original output filter inductor L 1 , L 2 The current flowing through the reset capacitor begins to gradually transfer to the diode D 1 The corresponding current flowing through the reset capacitor Cr gradually decreases.

[0048] Mode 6: If Figure 7 As shown, in this stage, the third power switch tube Q3 and the fourth power switch tube Q4 are turned on. When the current of the reset capacitor Cr decreases to 0 and then reverses, it means that the two filter inductors L 1 , L 2 The current has been completely transferred to the diode D 1 , the full-bridge converter passes through the diode D 1 The reset capacitor starts to be charged, and the transformer primary voltage is clamped to nV again. Cr , the primary leakage current is in the input voltage and nV Cr The difference Vin-nV Cr The current in the secondary filter inductor L1 increases rapidly in the reverse direction. 1 The secondary filter inductor L 2 The current through D 1 And the secondary winding of the transformer to supply energy to the load.

[0049] Mode 7: If Figure 8 As shown, at this time, the second power switch tube Q2 is turned off, and the primary current I p The junction capacitance of the second power switch tube Q1 and the second power switch tube Q2 is charged. Since the primary current is large, the first power switch tube can easily achieve zero voltage turn-on. 1It is still conducting, and the voltage on both sides of the transformer remains nV Cr unchanged, and is completely added to the primary leakage inductance L of the transformer r The two ends cause the primary current to decrease rapidly. The secondary filter inductor L1 and L 2 The current also flows from the diode D 1 The phase is switched to the reset capacitor Cr, and the current of Cr gradually decreases and then increases in the reverse direction.

[0050] Mode 8: Fig. 9 As shown, when the primary current decreases to I p =I m +(I L1 -I L2 ) / n, this mode starts, at which time the first power switch tube Q1 and the third power switch tube Q3 are turned on. The secondary output filter inductor L 1 , L 2 The current has completed the phase change and completely flows through the reset capacitor Cr. Diode D 1 Shutdown, shutdown voltage is nV Cr The transformer primary voltage is 0 at this time, and the primary current maintains I p =I m +(I L1 -I L2 ) / n remains unchanged.

[0051] Mode 9: Fig.10 As shown, at this time, the third power switch tube Q3 is turned off, and the primary current provides energy for the switching of the third power switch tube Q3 and the fourth power switch tube Q4, and the magnitude is I p =I m +(I L1 -I L2 ) / n. The primary current is now excited by the magnetizing inductance L m and output filter inductor L 1 , L 2 The primary current is clamped so that it remains basically unchanged during the commutation process, and the fourth power switch Q4 is turned on with zero voltage. The primary voltage of the transformer begins to gradually rise from 0 to nV Cr , the secondary diodes D1 and D2 remain turned off.

[0052] Mode 10: Fig.11 As shown, when the transformer primary voltage rises to nV C When r, the secondary diode D2 starts to conduct. The primary side of the transformer is clamped to nV Cr The primary leakage inductance is in The difference between the transformer primary voltage and the transformer primary voltage is nV Cr Under this condition, the current quickly changes from I p =I m +(I L1-I L2 ) / n decreases to 0 and then increases in the reverse direction, the secondary output filter inductor L 1 , L 2 The current also begins to gradually flow from the reset capacitor Cr to the diode D 2 The current on the reset capacitor gradually decreases to 0. All modes are now terminated.

[0053] Compared with the prior art, the full-bridge converter based on the adaptive current reset rectifier circuit proposed in the present invention utilizes the adaptive current reset function, which greatly reduces the conduction loss of the full-bridge converter during the freewheeling period. Since the secondary diode first rises to a smaller value when it is turned off, its reverse recovery loss and voltage overshoot are also greatly reduced. The present invention changes the disadvantage that the traditional full-bridge converter cannot achieve soft switching under light load conditions because the leakage inductance alone provides the lagging bridge arm commutation energy. The excitation inductance and the output filter inductance are used to jointly provide energy for the lagging bridge arm commutation, so that soft switching within the full load range can be easily achieved. The present invention does not have a stage where two rectifier diodes are turned on, so there is no duty cycle loss, breaking the limitation that the traditional full-bridge converter cannot be applied to ultra-high frequency due to duty cycle loss. The present invention has a simple structure, low cost, and high practical value.

[0054] The "first" and "second" in the names of "first" and "second" mentioned in the embodiments of the present application are only used as name identifications and do not represent their importance rankings.

[0055] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A full-bridge converter based on an adaptive current reset rectifier circuit, characterized in that: It includes an inverter circuit, a transformer circuit and an adaptive current reset rectifier circuit connected in sequence; The inverter circuit includes a full-bridge inverter unit and an input power supply for supplying power to the full-bridge inverter unit, which is used to provide an inverter signal for the transformer circuit; the inverter circuit includes an advanced bridge arm, a lagging bridge arm, an input power supply, and an advanced bridge arm and a lagging bridge arm trench full-bridge inverter unit; the advanced bridge arm includes a first power switch tube Q1 and a second power switch tube Q2, and the lagging bridge arm includes a third power switch tube Q3 and a fourth power switch tube Q4; the positive electrode of the input power supply is connected to the drain of the first power switch tube Q1 and the drain of the third power switch tube Q3, the source of the first power switch tube Q1 is connected to the drain of the second power switch tube Q2, and the midpoint thereof is used as the midpoint of the advanced bridge arm, the source of the third power switch tube Q3 is connected to the drain of the fourth power switch tube Q4, and the midpoint thereof is used as the midpoint of the lagging bridge arm, and the negative electrode of the input power supply is connected to the source of the second power switch tube Q2 and the source of the fourth power switch tube Q4; the midpoint of the advanced bridge arm and the midpoint of the lagging bridge arm are used as the positive output terminal and the negative output terminal of the inverter circuit respectively; The transformer circuit includes a transformer with a center tap, the primary side of the transformer is connected to the bridge arm of the full-bridge inverter unit, and the secondary side of the transformer is connected to the adaptive current reset rectifier circuit, which is used to provide energy to the load of the secondary side and the reset capacitor Cr; The adaptive current reset rectifier circuit is used to provide an output voltage after phase switching through a reset capacitor and a diode, and to quickly reset the primary freewheeling current.

2. A full-bridge converter based on an adaptive current reset rectifier circuit according to claim 1, characterized in that: The transformer circuit includes a transformer with a center tap; the same-name end of the primary side of the transformer is connected to the positive output end of the inverter circuit through the leakage inductance Lr, the opposite-name end of the primary side of the transformer is connected to the negative output end of the inverter circuit, and the same-name end of the primary side of the transformer is connected to the negative output end of the inverter circuit through the excitation inductance L m The transformer is connected to the opposite-name terminal of the primary side of the transformer, the secondary side of the transformer includes a center tap, and the same-name terminal, the opposite-name terminal and the center tap of the secondary side of the transformer are all connected to the adaptive current reset rectifier circuit.

3. A full-bridge converter based on an adaptive current reset rectifier circuit according to claim 2, characterized in that: The transformation ratio of the transformer is n:1:1, where n represents the transformation ratio coefficient; the center tap of the secondary side of the transformer is both the opposite-name end of the upper winding and the same-name end of the lower winding.

4. A full-bridge converter based on an adaptive current reset rectifier circuit according to claim 2, characterized in that: The adaptive current reset rectifier circuit includes a first rectifier diode D1, a second rectifier diode D2, a first filter inductor L1, a second filter inductor L2, a reset capacitor Cr, an output capacitor C o , load R; parallel output capacitor C o One end of the load R is connected to the negative terminal of the first rectifier diode D1 through the first filter inductor L1, and the output capacitor C o The other end of the load R is connected to the positive terminal of the first rectifier diode D1; the output capacitor C o One end of the load R is connected to the negative terminal of the second rectifier diode D2 through the second filter inductor L2, and the output capacitor C o The other end of the load R is connected to the positive terminal of the second rectifier diode D2; the negative terminal of the first rectifier diode D1 is connected to the same-name terminal of the secondary side of the transformer in the transformer circuit, the negative terminal of the second rectifier diode D2 is connected to the opposite-name terminal of the secondary side of the transformer in the transformer circuit, and the positive terminal of the second rectifier diode D2 is connected to the center tap of the transformer in the transformer circuit through the reset capacitor Cr.

5. A full-bridge converter based on an adaptive current reset rectifier circuit according to claim 4, characterized in that: The inductance values ​​of the first filter inductor L1 and the second filter inductor L2 are equal.

6. A full-bridge converter based on an adaptive current reset rectifier circuit according to claim 5, characterized in that: The calculation formulas for the inductance values ​​of the first filter inductor L1 and the second filter inductor L2 include: Among them, V o represents the output voltage, D represents the phase shift duty cycle, f represents the switching frequency, Indicates the ripple factor of the output filter inductor current.

7. A full-bridge converter based on an adaptive current reset rectifier circuit according to claim 4, characterized in that: The reset capacitor Cr has a relatively large capacitance, and its calculation formula includes: Where n is the transformer turns ratio, D is the phase shift duty cycle, and I o represents the output current, f represents the switching frequency, V in Indicates the input voltage, Indicates the ripple factor of the reset capacitor voltage.

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