CN111181411B

CN111181411B - Variable/fixed bus voltage ultra-wide gain range bidirectional dc/dc converter

Info

Publication number: CN111181411B
Application number: CN202010163521.4A
Authority: CN
Inventors: 王浩宇; 周明德
Original assignee: ShanghaiTech University
Current assignee: ShanghaiTech University
Priority date: 2020-03-10
Filing date: 2020-03-10
Publication date: 2021-07-16
Anticipated expiration: 2040-03-10
Also published as: CN111181411A

Abstract

The present invention provides a bidirectional dc/dc converter with a variable/constant bus voltage and an ultra-wide gain range. The present invention: 1) improves the design of the traditional wide-gain range bidirectional converter, while retaining its advantages, aiming at the first The primary loss is large, the secondary high gain and high efficiency are difficult to achieve, the voltage stress of the switching device is large, and the overall gain range is narrow. 2) The traditional H5 bridge resonant circuit is improved. Under the condition of retaining its advantages, the problems of complex transformer structure, large voltage stress of rectifier tube, complex mode switching control and low reverse gain are improved.

Description

Variable/fixed bus voltage ultra-wide gain range bidirectional dc/dc converter

Technical Field

The invention relates to a variable/fixed bus voltage ultra-wide gain range bidirectional dc/dc converter based on an H5 reconfigurable bridge.

Background

A wide gain range bi-directional converter having a topology substantially as shown in figure 1. The input voltage may be either ac or dc. The input voltage is supplied to the energy storage capacitor and the isolation bidirectional converter after passing through a PWM converter. For ac inputs, PWM converters typically employ a bridgeless rectification architecture, such as totem pole PFC.

In a conventional wide gain range bidirectional converter design, the following advantages are provided:

1) the dc/dc stage is simple to control. The two-stage design ensures that the post-stage dc/dc stage only bears a DCX working mode with the function of isolating the fixed voltage ratio of lifting without frequency modulation control, so that the switching frequency is fixed.

2) The power density is high. Because of the fixed switching frequency, the switching frequency can be higher. This allows the magnetic element to be substantially reduced in volume.

3) Is easy to produce. The design of the dc/dc stage transformer only needs to consider the performance under the fixed switching frequency, and the design and the adoption of the PCB transformer are convenient, so that the production can be highly automated.

It has some disadvantages:

1) the first-stage gain is high in requirement and large in loss. Since the latter stages use the DCX structure, the gain is all provided by the first stage. A high gain first stage may cause the efficiency of the first stage to be substantially reduced.

2) Secondary high gain high efficiency is difficult to achieve. Since the secondary uses a dc/dc bi-directional isolation converter, it is usually a dual active bridge topology or a resonant converter topology. In the design of the traditional H4 bridge (full bridge) or half bridge, the two topologies have the defects of large current stress, poor soft switching performance, low efficiency and the like when the wide gain range is realized.

3) The switching device has a large voltage stress. Since the gain is provided primarily by the first stage, and the lowest output voltage of the first stage is typically fixed, the maximum bus voltage between the first and second stages is high in conventional designs. The high voltage variable bus range makes it necessary to use high voltage class devices. However, for miniaturization of the converter volume, it is necessary to increase the switching frequency. Because the performance of a high-voltage-resistant class device is inferior to that of a low-voltage-resistant device with the same technology when the high-voltage-resistant class device works at high frequency, the traditional design scheme of the bidirectional converter with the wide gain range limits the further improvement of the switching frequency.

4) The overall gain range is narrow. The gain range provided by the traditional wide-gain-range bidirectional converter design scheme is narrow and is about 1-2 times. However, for an energy storage system, especially for a hybrid energy storage system, the wider the voltage range, the higher the proportion of low-voltage energy storage devices such as super capacitors in the energy storage system. Conventional wide gain range bidirectional converter designs reduce the dynamic response capability of the energy storage system.

In addition, the bi-directional isolated converter scheme applied in the configuration of fig. 1 can provide a dc/dc converter with a wide gain range, and the mainstream scheme is a resonant converter. The resonant converter has the problem of large circulating current under the operation of a wide gain range, and the main reason is that the soft switching performance under the wide gain range needs to be realized by improving the circulating current.

In order to adapt to a wide range of input/output applications without significantly increasing the circulating current, popular resonant converters, such as LLC, etc., a conventional full-bridge/half-bridge inverter circuit is usually changed to a multi-level scheme, such as a midpoint clamped three-level scheme. The advantages are that: the circulating current loss in the resonant cavity can be reduced. The disadvantages are as follows: more switching devices are used.

For example, a midpoint clamp type three-level circuit is used, and the inverter bridge uses as many as 6 active devices, 50% more than the full bridge circuit and 200% more than the half bridge circuit. An improved multi-level inverter bridge scheme: the H5 bridge inversion scheme, as shown in fig. 2, only adds one device to the full bridge circuit, and realizes gain mode control of two resonators, providing 6 different gain modes. The advantages are that:

1) the gain range is wide.

2) And the circulating current loss is small.

3) The device stress is not increased compared to full/half bridge.

4) ZVS conditions are improved.

However, the disadvantages are:

1) the transformer has a complicated structure. Two three-winding transformers need to be used, which is difficult for magnetic design.

2) The voltage stress of the rectifier tube is large. The secondary rectifier tube is connected in series with the leakage inductance of the transformer, and a larger voltage peak exists when the inverter tube does not realize zero current turn-off.

3) The modal switching control is complicated. Because the two output capacitors on the secondary side clamp the output voltages, the voltages on the output capacitors are inconsistent before and after the mode switching, the output capacitor charge rebalancing control algorithm is complex, and the smooth switching is not easy to realize.

4) The reverse gain is lower. Because the A side and the B side of the resonant cavity are asymmetric, the gain of the resonant cavity is low during reverse power transmission, and the purpose of wide gain can be realized only by enabling the converter to work in a current interrupted mode. Meanwhile, the reverse transmission power is lower than that in the forward transmission, and because the reverse transmission power works in a current interruption mode, the current stress in the reverse transmission is larger than that in the forward transmission power.

Disclosure of Invention

The purpose of the invention is: 1) the design of the traditional wide-gain-range bidirectional converter is improved, and under the condition of keeping the advantages of the traditional wide-gain-range bidirectional converter, the problems that the loss of a first stage is large, the high gain and the high efficiency of a second stage are difficult to realize, the voltage stress of a switching device is large, the integral gain range is narrow and the like are improved; 2) the conventional H5 bridge resonant circuit is improved. Under the condition of keeping the advantages of the transformer, the problems of complex structure of the transformer, large voltage stress of a rectifier tube, complex mode switching control, lower reverse gain and the like are improved.

In order to achieve the above object, the present invention provides a bidirectional dc/dc converter with ultra wide gain range for variable/fixed bus voltage, comprising:

by a switching tube Q with a body diode_p1Switch with body diodeTube Q_p2Switching tube Q with body diode_p3Switching tube Q with body diode_p4And a switching tube Q with a body diode_p5The H5 bridge inverter circuit is formed, the input end of the H5 bridge inverter circuit is connected with an external power supply, and the H5 bridge inverter circuit is provided with an upper output end, a middle output end and a lower output end;

two-winding transformer T₁And a two-winding transformer T₂(ii) a Two-winding transformer T₁The primary side of the transformer forms a transformer T with two windings, an upper input end I and a lower input end I₁The secondary side of the transformer forms an upper output end I and a lower output end I, and the transformer T₁The upper input end I and the upper output end I are homonymous ends; two-winding transformer T₂The primary side of the transformer forms an upper input end two and a lower input end two, two-winding transformer T₂The secondary side of the transformer forms an upper output end II and a lower output end II, and the transformer T₂The upper input end II and the lower output end II are homonymous ends;

two-winding transformer T₁The upper input end of the transformer T is connected with the upper output end of the H5 bridge inverter circuit through the resonant cavity I, and the transformer T with two windings₁Lower input end one and two winding transformer T₂The upper input end two of the transformer is connected with the midpoint output end of the H5 bridge inverter circuit, and the transformer T with two windings₂The lower input end II of the resonant cavity II is connected with the lower output end of the H5 bridge inverter circuit through the resonant cavity II;

two-winding transformer T₁Lower output end one and two winding transformer T₂Is connected to the upper output terminal two, thereby connecting the two-winding transformer T₁Secondary winding and two-winding transformer T₂The secondary windings are connected in series;

by a switching tube Q_s1And a switching tube Q_s2And a switching tube Q_s3And a switching tube Q_s4Formed full-bridge rectification circuit, two-winding transformer T₁The upper output end of the transformer T is connected with one input end of a full-bridge rectification circuit through a resonant cavity III, and the transformer T with two windings₂The lower output end two of the full-bridge rectifier circuit is connected with the other input end of the full-bridge rectifier circuit;

and the filter circuit is connected with the output end of the full-bridge rectifying circuit.

Preferably, the first resonant cavity, the second resonant cavity and the third resonant cavity are all composed of an inductor and a capacitor connected in series.

Preferably, the filter circuit is a capacitor C connected to the output end of the full-bridge rectification circuit_B。

Under the same circuit topology, the invention is divided into the following two control modes, which are applicable to different application scenes and design parameters:

1) the bus voltage variable ultra-wide gain range bidirectional dc/dc converter comprises: the method is applied to input variable bus voltage, a converter fixes switching frequency and switching duty ratio, a gain range is controlled by utilizing a bus voltage range and a switching working mode, and the parameter design is similar to a direct current transformer DCX mode at the moment;

2) the fixed bus voltage ultra-wide gain range bidirectional dc/dc converter comprises: and fixing the bus voltage and the switching duty ratio, adjusting the switching frequency and switching the working mode to control the gain range, wherein the parameter design is similar to a frequency modulation PFM converter mode.

In the application of the variable bus voltage, the characteristics of simple control, high power density and easy production of a dc/dc stage of a traditional variable bus voltage wide-gain-range bidirectional dc/dc converter are inherited. Meanwhile, the application of the H5 bridge and the optimized transformer structure and rectification post-stage structure improve the problems of complex transformer structure, large voltage stress of a rectifier tube, complex modal switching control and lower reverse gain of the traditional H5 bridge resonant bidirectional dc/dc converter. Meanwhile, the defects that the first-level loss of the traditional variable bus voltage structure is large, the secondary high-gain high efficiency is difficult to realize, the voltage stress of a switching device is large, and the whole gain range is narrow are overcome.

In the application of the bidirectional dc/dc converter with the ultra-wide gain range of the fixed bus voltage, the application of the H5 bridge and the optimized transformer structure and the rectification post-stage structure improve the problems of complex transformer structure, large voltage stress of a rectification tube, complex modal switching control and lower reverse gain of the traditional H5 bridge resonant bidirectional dc/dc converter.

Based on the optimized transformer structure and the rectification post-stage structure, the invention has the following beneficial effects:

1) due to the application of the symmetrical resonant cavity, the gain of reverse power transmission is improved.

2) Two three-winding transformers are improved into two-winding transformers, and the difficulty of magnetic design (transformer design) of a system is reduced.

3) Simultaneous, two-winding transformer T₁And a two-winding transformer T₂The windings on the B side are connected in series, so that the transformer T with two windings is convenient to use₁And a two-winding transformer T₂And the magnetic loss is reduced by the integrated design.

4) At the moment of switching circulation, the switching tube Q_s1And a switching tube Q_s3The body diodes in (1) may freewheel when they lose ZCS from each other, Q_s2And Q_s4In the same way, the defect of large voltage stress of the rectifier tube is overcome.

5) Because the scheme does not need to arrange an output clamping capacitor for each resonant cavity, the number of the filter capacitors at the output end is reduced to 1. Meanwhile, the transition amount of the charge state of the capacitor during mode switching is reduced, the voltage transition problem of the output capacitor is eliminated, and the mode switching control is improved.

The working mode of the reconfigurable resonant converter is expanded from six modes to twelve modes of the traditional H5 bridge resonant converter, and the output of wide-range step (variable bus voltage fixed frequency fixed duty ratio control) or continuous (fixed bus voltage fixed frequency fixed duty ratio control) gain is realized through the switching control of the twelve modes (forward direction) or eight modes (reverse direction). The method has the following specific beneficial effects:

in a variable bus voltage application:

1) the gain range of the secondary stage is enlarged, and the problem that the high gain and high efficiency of the secondary stage are difficult to realize is solved;

2) the bus voltage range is compressed, and the problem of large voltage stress of a switching device is solved;

3) the gain requirement of the first-stage PWM converter is reduced, and the efficiency of the first-stage PWM converter is improved;

4) the application of the twelve mode/eight mode greatly widens the integral gain range of the system and solves the problem of narrow integral gain range.

In bus-bar voltage applications:

the optimized transformer structure and the rectification structure improve the problems of complex transformer structure, large voltage stress of a rectification tube, complex modal switching control and lower reverse gain of the traditional H5 bridge resonant bidirectional dc/dc converter.

The application of the twelve modes greatly widens the gain range of the system under the condition of maintaining the circulation loss unchanged, so that the application scene of the converter is wider. For example, more energy storage units may be accommodated in an energy storage system application; in automotive charging applications, deep discharge batteries may be charged, and the like.

Drawings

FIG. 1 is a conventional wide gain range two-stage power architecture;

fig. 2 is a topology architecture of a conventional H5 bridge bidirectional resonant converter;

FIG. 3 is a bidirectional dc/dc converter with ultra-wide gain range of variable/fixed bus voltage based on H5 bridge according to the present invention;

FIG. 4 is an improved rectification scheme and transformer structure thereof proposed by the present invention;

FIG. 5 is a switch configuration for the forward mode of operation 1;

FIG. 6 is a waveform of a critical voltage and current in the forward working mode 1;

FIG. 7 is a forward mode of operation 2 switch configuration;

FIG. 8 is a key voltage current waveform in the forward mode of operation 2;

FIG. 9 is a forward mode of operation 3 switch configuration;

fig. 10 is a waveform of a key voltage and current in the forward operation mode 3;

FIG. 11 is a forward mode of operation 4 switch configuration;

FIG. 12 is a key voltage current waveform in the forward mode of operation 4;

FIG. 13 is a forward mode 5 switch configuration;

FIG. 14 is a key voltage current waveform in the forward mode of operation 5;

FIG. 15 is a forward operating mode 6 switch configuration;

FIG. 16 is a key voltage current waveform in the forward mode of operation 6;

FIG. 17 is a switch configuration for the forward mode of operation 7;

FIG. 18 is a key voltage current waveform for the forward mode of operation 7;

FIG. 19 is a forward operating mode 8 switch configuration;

FIG. 20 is a key voltage current waveform in the forward mode of operation 8;

FIG. 21 is a forward mode 9 switch configuration;

FIG. 22 is a key voltage current waveform in the forward mode of operation 9;

FIG. 23 is a switch configuration for the forward mode of operation 10;

FIG. 24 is a key voltage current waveform for the forward mode of operation 10;

FIG. 25 is a switch configuration for the forward mode of operation 11;

FIG. 26 is a key voltage current waveform for the forward mode of operation 11;

FIG. 27 is a switch configuration for the forward mode of operation 12;

FIG. 28 is a key voltage current waveform for the forward mode of operation 12;

FIG. 29 is a reverse mode of operation 1 switch configuration;

FIG. 30 is a key voltage current waveform for reverse mode of operation 1;

FIG. 31 is a reverse mode 2 switch configuration;

FIG. 32 is a key voltage current waveform for reverse mode of operation 2;

FIG. 33 is a reverse mode of operation 3 switch configuration;

FIG. 34 is a key voltage current waveform in reverse mode of operation 3;

FIG. 35 is a reverse operating mode 4 switch configuration;

FIG. 36 is a key voltage current waveform for the reverse mode of operation 4;

FIG. 37 is a reverse mode 5 switch configuration;

FIG. 38 is a key voltage current waveform for the reverse mode of operation 5;

FIG. 39 is a reverse mode 6 switch configuration;

FIG. 40 is a key voltage current waveform for the reverse mode of operation 6;

FIG. 41 is a reverse operating mode 7 switch configuration;

FIG. 42 is a key voltage current waveform for the reverse mode of operation 7;

FIG. 43 is a reverse mode 8 switch configuration;

fig. 44 is a key voltage current waveform in the reverse operation mode 8.

Detailed Description

The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.

The variable/fixed bus voltage ultra-wide gain range bidirectional dc/dc converter based on the H5 bridge is shown in figure 3. The optimized transformer structure and the rectification post-stage structure for the H5 bridge resonant converter are shown in FIG. 4. In FIG. 4, Z_rIs a secondary side cavity, L in FIG. 3_rsAnd C_rsForming a resonant cavity.

Specifically, the present invention comprises:

by a switching tube Q with a body diode_p1Switching tube Q with body diode_p2Switching tube Q with body diode_p3Switching tube Q with body diode_p4And a switching tube Q with a body diode_p5The H5 bridge inverter circuit is formed, the input end of the H5 bridge inverter circuit is connected with an external power supply, and the H5 bridge inverter circuit is provided with an upper output end, a middle output end and a lower output end;

two-winding transformer T₁And a two-winding transformer T₂(ii) a Two-winding transformer T₁The primary side of the transformer forms a transformer T with two windings, an upper input end I and a lower input end I₁The secondary side of the transformer forms an upper output end I and a lower output end I, and the transformer T₁The upper input end I and the upper output end I are homonymous ends; two-winding transformer T₂The primary side of the transformer forms an upper input end two and a lower input end two, two winding transformer T₂The secondary side of the transformer forms an upper output end two and a lower output end two, and the transformer T₂The upper input end II and the lower output end II are homonymous ends;

two-winding transformer T₁Via a resonant cavity I (series inductor L)_r1And a capacitor C_r1) Connected with the upper output end of the H5 bridge inverter circuit, and a two-winding transformer T₁Lower input end one and two winding transformer T₂The upper input end two of the transformer is connected with the midpoint output end of the H5 bridge inverter circuit, and the transformer T with two windings₂The second lower input end of the second resonant cavity is connected with the second resonant cavity (a series inductor L)_r2And a capacitor C_r2) The lower output end of the H5 bridge inverter circuit is connected;

by a switching tube Q_s1And a switching tube Q_s2And a switching tube Q_s3And a switching tube Q_s4Formed full-bridge rectification circuit, two-winding transformer T₁Via the resonant cavity III (series inductor L)_rsAnd a capacitor C_rs) A transformer T with two windings connected to one input of the full-bridge rectifier circuit₂The lower output end two of the full-bridge rectifier circuit is connected with the other input end of the full-bridge rectifier circuit;

by a single capacitor, capacitor C_BAnd the filter circuit is connected with the output end of the full-bridge rectifying circuit.

Different from the conventional H5 bridge resonant converter in fig. 3 are the structure of the transformer, the B-side rectifying structure and the output filtering structure, as shown in fig. 4.

Thanks to the structure of fig. 4, the operation mode of the reconfigurable resonant converter is expanded from six modes to twelve modes of the conventional H5 bridge resonant converter.

Fig. 5 to 28 show twelve working modes and key voltage and current waveforms of forward power transmission of the variable/fixed bus voltage ultra-wide gain range bidirectional dc/dc converter based on the H5 bridge. Fig. 29 to fig. 44 show twelve working modes and key voltage and current waveforms of the reverse power transmission of the bi-directional dc/dc converter based on the ultra-wide gain range of the variable/fixed bus voltage of the H5 bridge.

In forward power transmission:

mode 1: q_p1Giving an always-on signal. Q_p2,4And (4) half-bridge inversion. Q_s1,2,3,4Operating in a full bridge rectification state as shown in fig. 5. In the mode, the first A-side resonant cavity works in a half-bridge inversion input state, and the second A-side resonant cavity does not work. The B side works in a full-bridge rectification state. The gain in this mode is lowest. The critical voltage current waveform is shown in fig. 6.

Mode 2: q_p3Giving an always-on signal. Q_p2,4And (4) half-bridge inversion. Q_s1,2,3,4Operating in a full bridge rectification state as shown in fig. 7. In the mode, the first A-side resonant cavity does not work, and the second A-side resonant cavity works in a half-bridge inversion input state. The B side works in a full-bridge rectification state. The critical voltage current waveform is shown in fig. 8.

Modality 3: q_p1Giving an always-on signal. Q_p2,4And (4) half-bridge inversion. Q_s1,3Operating in voltage-doubler rectification mode, Q_s4Normally, as shown in fig. 9. In the mode, the first A-side resonant cavity works in a half-bridge inversion input state, and the second A-side resonant cavity does not work. The B side works in a voltage-doubling rectifying state. The critical voltage current waveform is shown in fig. 10.

Modality 4: q_p1,3Giving an always-on signal. Q_p2,4And (4) half-bridge inversion. Q_s1,2,3,4Operating in a full bridge rectification state as shown in fig. 11. In the mode, the first A-side resonant cavity works in a half-bridge inversion input state, and the second A-side resonant cavity works in a half-bridge inversion input state. The B side works in a full-bridge rectification state. The critical voltage current waveform is shown in fig. 12.

Mode 5: q_p3Giving an always-on signal. Q_p2,4And (4) half-bridge inversion. Q_s1,3Operating in voltage-doubler rectification mode, Q_s4Normally, as shown in fig. 13. In this mode, AThe first side resonant cavity does not work, and the second side resonant cavity A is in a half-bridge inversion input state. The B side works in a voltage-doubling rectifying state. The critical voltage current waveform is shown in fig. 14.

Modality 6: q_p3Giving an always-on signal. Q_p1,2,4,5Full bridge inversion. Q_s1,2,3,4Operating in the full bridge rectification state as shown in fig. 15. In the mode, the first A-side resonant cavity is in a full-bridge inversion input state, and the second A-side resonant cavity is in a half-bridge inversion input state. The B side works in a full-bridge rectification state. The critical voltage current waveform is shown in fig. 16.

Modality 7: q_p1Giving an always-on signal. Q_p2,3,4,5Full bridge inversion. Q_s1,2,3,4Operating in the full bridge rectification state as shown in fig. 17. In the mode, the first A-side resonant cavity is in a half-bridge inversion input state, and the second A-side resonant cavity is in a full-bridge inversion input state. The B side works in a full-bridge rectification state. The critical voltage current waveform is shown in fig. 18.

Modality 8: q_p5Giving an always-on signal. Q_p1,2,3,4Full bridge inversion. Q_s1,2,3,4Operating in the full bridge rectification state as shown in fig. 19. In the mode, the first A-side resonant cavity is in a full-bridge inversion input state, and the second A-side resonant cavity is in a full-bridge inversion input state. The B side works in a full-bridge rectification state. The critical voltage current waveform is shown in fig. 20.

Modality 9: q_p1,3Giving an always-on signal. Q_p2,4And (4) half-bridge inversion. Q_s1,3Operating in voltage-doubler rectification mode, Q_s4Normally, as shown in fig. 21. In the mode, the first A-side resonant cavity is in a half-bridge inversion input state, and the second A-side resonant cavity is in a half-bridge inversion input state. The B side works in a voltage-doubling rectifying state. The critical voltage current waveform is shown in fig. 22.

Modality 10: q_p3Giving an always-on signal. Q_p1,2,4,5Full bridge inversion. Q_s1,3Operating in voltage-doubler rectification mode, Q_s4Normally, as shown in fig. 23. In the mode, the first A-side resonant cavity is in a full-bridge inversion input state, and the second A-side resonant cavity is in a half-bridge inversion input state. The B side works in a voltage-doubling rectifying state. The critical voltage current waveform is shown in fig. 24.

Modality 11: q_p1Giving an always-on signal. Q_p2,3,4,5Full bridge inversion. Q_s1,3Operating in voltage-doubler rectification mode, Q_s4Normally, as shown in fig. 25. In the mode, the first A-side resonant cavity is in a half-bridge inversion input state, and the second A-side resonant cavity is in a full-bridge inversion input state. The B side works in a voltage-doubling rectifying state. The critical voltage current waveform is shown in fig. 26.

Modality 12: q_p5Giving an always-on signal. Q_p1,2,3,4Full bridge inversion. Q_s1,3Operating in voltage-doubler rectification mode, Q_s4Normally, as shown in fig. 27. In the mode, the first A-side resonant cavity is in a full-bridge inversion input state, and the second A-side resonant cavity is in a full-bridge inversion input state. The B side works in a voltage-doubling rectifying state. The critical voltage current waveform is shown in fig. 28.

Reverse power transmission:

mode 1: q_p1 Q_p3Giving an always-on signal. Q_p2,4And synchronous rectification is realized. Q_s1,2,3,4And the inverter operates in a full-bridge inversion state, as shown in fig. 29. In the mode, the first A-side resonant cavity works in a voltage-multiplying rectification state, and the second A-side resonant cavity works in a voltage-multiplying rectification state. The side B works in a full-bridge inversion state. The critical voltage current waveform is shown in fig. 30.

Mode 2: q_p3Giving an always-on signal. Q_p1,2,4,5And synchronous rectification is realized. Q_s1,2,3,4And the inverter operates in a full-bridge inversion state, as shown in fig. 31. In the mode, the first A-side resonant cavity works in a full-bridge rectification state, and the second A-side resonant cavity works in a voltage-multiplying rectification state. The side B works in a full-bridge inversion state. The critical voltage current waveform is shown in fig. 32.

Modality 3: q_p1Giving an always-on signal. Q_p2,3,4,5And synchronous rectification is realized. Q_s1,2,3,4And the inverter operates in a full-bridge inversion state, as shown in fig. 33. In the mode, the first A-side resonant cavity works in a voltage-multiplying rectification state, and the second A-side resonant cavity works in a full-bridge rectification state. The side B works in a full-bridge inversion state. The critical voltage current waveform is shown in fig. 34.

Modality 4: q_p5Giving an always-on signal. Q_p1,2,3,4And synchronous rectification is realized. Q_s1,2,3,4Work inFull bridge inversion state, as shown in fig. 35. In the mode, the first A-side resonant cavity works in a full-bridge rectification state, and the second A-side resonant cavity works in a full-bridge rectification state. The side B works in a full-bridge inversion state. The critical voltage current waveform is shown in fig. 36.

Mode 5: q_p1,3Giving an always-on signal. Q_p2,4And synchronous rectification is realized. Q_s1,3Operating in half-bridge inverter mode, Q_s4Normally, as shown in fig. 37. In the mode, the first A-side resonant cavity is in a voltage-multiplying rectification state, and the second A-side resonant cavity is in a voltage-multiplying rectification state. The side B works in a half-bridge inversion state. The critical voltage current waveform is shown in fig. 38.

Modality 6: q_p3Giving an always-on signal. Q_p1,2,4,5And synchronous rectification is realized. Q_s1,3Operating in half-bridge inverter mode, Q_s4Normally, as shown in fig. 39. In the mode, the first A-side resonant cavity is in a full-bridge rectification state, and the second A-side resonant cavity is in a voltage-multiplying rectification state. The side B works in a half-bridge inversion state. The critical voltage current waveform is shown in fig. 40.

Modality 7: q_p1Giving an always-on signal. Q_p2,3,4,5And synchronous rectification is realized. Q_s1,3Operating in half-bridge inverter mode, Q_s4Normally, as shown in fig. 41. In the mode, the first A-side resonant cavity is in a voltage-doubling rectification state, and the second A-side resonant cavity is in a full-bridge rectification state. The side B works in a half-bridge inversion state. The critical voltage current waveform is shown in fig. 42.

Modality 8: q_p5Giving an always-on signal. Q_p1,2,3,4And synchronous rectification is realized. Q_s1,3Operating in half-bridge inverter mode, Q_s4Normally, as shown in fig. 43. In the mode, the first A-side resonant cavity is in a full-bridge rectification state, and the second A-side resonant cavity is in a full-bridge rectification state. The side B works in a half-bridge inversion state. The critical voltage current waveform is shown in fig. 44.

Claims

1. A variable/fixed bus voltage ultra wide gain range bi-directional dc/dc converter comprising:

by a switching tube Q with a body diode_p1Switching tube Q with body diode_p2Has a body twoSwitching tube Q of polar tube_p3Switching tube Q with body diode_p4And a switching tube Q with a body diode_p5The H5 bridge inverter circuit is formed, the input end of the H5 bridge inverter circuit is connected with an external power supply, and the H5 bridge inverter circuit is provided with an upper output end, a middle output end and a lower output end;

the filter circuit is connected with the output end of the full-bridge rectifying circuit;

to-be-connected two-winding transformerT₁And a two-winding transformer T₂The primary side of the transformer is defined as side A, and is connected with a two-winding transformer T₁And a two-winding transformer T₂The side circuit connected with the secondary side is defined as a side B, and then:

in forward power transmission:

mode 1: switch tube Q_p1For normally on signal, the switching tube Q_p2And a switching tube Q_p4The half-bridge inversion is carried out, and the full-bridge rectification circuit works in a full-bridge rectification state; in the mode, the first side resonant cavity works in a half-bridge inversion input state, the second side resonant cavity does not work, the B side works in a full-bridge rectification state, and the gain in the mode is lowest;

mode 2: switch tube Q_p3For normally on signal, the switching tube Q_p2And a switching tube Q_p4The half-bridge inversion is carried out, and the full-bridge rectification circuit works in a full-bridge rectification state; in the mode, the first A-side resonant cavity does not work, the second A-side resonant cavity works in a half-bridge inversion input state, and the second B-side resonant cavity works in a full-bridge rectification state;

modality 3: switch tube Q_p1For normally on signal, the switching tube Q_p2And a switching tube Q_p4Half-bridge inverter, switch tube Q_s1And a switching tube Q_s3Working in voltage-multiplying rectification state, the switching tube Q_s4Normally open; in the mode, the first side resonant cavity works in a half-bridge inversion input state, the second side resonant cavity does not work, and the B side works in a voltage-multiplying rectification state;

modality 4: switch tube Q_s1And a switching tube Q_s3For normally on signal, the switching tube Q_p2And a switching tube Q_p4The half-bridge inversion is carried out, and the full-bridge rectification circuit works in a full-bridge rectification state; in the mode, the first side resonant cavity works in a half-bridge inversion input state, the second side resonant cavity works in a half-bridge inversion input state, and the B side works in a full-bridge rectification state;

mode 5: switch tube Q_p3For normally on signal, the switching tube Q_p2And a switching tube Q_p4Half-bridge inverter, switch tube Q_s1And a switching tube Q_s3Working in voltage-multiplying rectification state, the switching tube Q_s4Normally open; in the mode, the first A-side resonant cavity does not work, and the second A-side resonant cavity is in inverse half-bridgeThe input state is changed, and the side B works in a voltage-multiplying rectification state;

modality 6: switch tube Q_p3For normally on signal, the switching tube Q_p1And a switching tube Q_p2And a switching tube Q_p4And a switching tube Q_p5Full-bridge inversion, wherein the full-bridge rectification circuit works in a full-bridge rectification state; in the mode, the first side resonant cavity is in a full-bridge inversion input state, the second side resonant cavity is in a half-bridge inversion input state, and the B side works in a full-bridge rectification state;

modality 7: switch tube Q_p1For normally on signal, the switching tube Q_p2And a switching tube Q_p3And a switching tube Q_p4And a switching tube Q_p5Full-bridge inversion, wherein the full-bridge rectification circuit works in a full-bridge rectification state; in the mode, the first side resonant cavity is in a half-bridge inversion input state, the second side resonant cavity is in a full-bridge inversion input state, and the B side works in a full-bridge rectification state;

modality 8: switch tube Q_p5For normally on signal, the switching tube Q_p1And a switching tube Q_p2And a switching tube Q_p3And a switching tube Q_p4Full-bridge inversion, wherein the full-bridge rectification circuit works in a full-bridge rectification state; in the mode, the first side resonant cavity is in a full-bridge inversion input state, the second side resonant cavity is in a full-bridge inversion input state, and the B side works in a full-bridge rectification state;

modality 9: switch tube Q_p1And a switching tube Q_p3For normally on signal, the switching tube Q_p2And a switching tube Q_p4Switching tube Q_s1And a switching tube Q_s3Working in voltage-multiplying rectification state, the switching tube Q_s4Normally open; in the mode, the first side resonant cavity is in a half-bridge inversion input state, the second side resonant cavity is in a half-bridge inversion input state, and the B side works in a voltage-multiplying rectification state;

modality 10: switch tube Q_p3For normally on signal, the switching tube Q_p1And a switching tube Q_p2And a switching tube Q_p4And a switching tube Q_p5Full bridge inverter, switch tube Q_s1And a switching tube Q_s3Working in voltage-multiplying rectification state, the switching tube Q_s4Normally open; in the mode, the first A-side resonant cavity is in a full-bridge inversion input state, and the second A-side resonant cavity is in a half-bridge inversion input stateIn the state, the side B works in a voltage-multiplying rectification state;

modality 11: switch tube Q_p1For normally on signal, the switching tube Q_p2And a switching tube Q_p3And a switching tube Q_p4And a switching tube Q_p5Full bridge inverter, switch tube Q_s1And a switching tube Q_s3Working in voltage-multiplying rectification state, the switching tube Q_s4Normally open; in the mode, the first side resonant cavity is in a half-bridge inversion input state, the second side resonant cavity is in a full-bridge inversion input state, and the B side works in a voltage-multiplying rectification state;

modality 12: switch tube Q_p5For normally on signal, the switching tube Q_p1And a switching tube Q_p2And a switching tube Q_p3And a switching tube Q_p4Full bridge inverter, switch tube Q_s1And a switching tube Q_s3Working in voltage-multiplying rectification state, the switching tube Q_s4(ii) a In the mode, the first side resonant cavity is in a full-bridge inversion input state, the second side resonant cavity is in a full-bridge inversion input state, and the B side works in a voltage-multiplying rectification state;

reverse power transmission:

mode 1: switch tube Q_p1And a switching tube Q_p3For normally on signal, the switching tube Q_p2And a switching tube Q_p4Synchronous rectification is realized, and the full-bridge rectification circuit works in a full-bridge inversion state; in the mode, the first A-side resonant cavity works in a voltage-multiplying rectification state, the second A-side resonant cavity works in a voltage-multiplying rectification state, and the second B-side resonant cavity works in a full-bridge inversion state;

mode 2: switch tube Q_p3For normally on signal, the switching tube Q_p1And a switching tube Q_p2And a switching tube Q_p4And a switching tube Q_p5Synchronous rectification is realized, and the full-bridge rectification circuit works in a full-bridge inversion state; in the mode, the first side resonant cavity works in a full-bridge rectification state, the second side resonant cavity works in a voltage-multiplying rectification state, and the B side works in a full-bridge inversion state;

modality 3: switch tube Q_p1For normally on signal, the switching tube Q_p2And a switching tube Q_p3And a switching tube Q_p4And a switching tube Q_p5Synchronous rectification is realized, and the full-bridge rectification circuit works in a full-bridge inversion state; in this mode, side AThe resonant cavity I works in a voltage-multiplying rectification state, the resonant cavity II at the side A works in a full-bridge rectification state, and the resonant cavity II at the side B works in a full-bridge inversion state;

modality 4: switch tube Q_p5For normally on signal, the switching tube Q_p1And a switching tube Q_p2And a switching tube Q_p3And a switching tube Q_p4Synchronous rectification is realized, and the full-bridge rectification circuit works in a full-bridge inversion state; in the mode, the first side resonant cavity works in a full-bridge rectification state, the second side resonant cavity works in a full-bridge rectification state, and the B side works in a full-bridge inversion state;

mode 5: switch tube Q_p1And a switching tube Q_p3For normally on signal, the switching tube Q_p2And a switching tube Q_p4Realize synchronous rectification, switch tube Q_s1And a switching tube Q_s3Operating in half-bridge inverter mode, switching tube Q_s4Normally open; in the mode, the first resonant cavity at the side A is in a voltage-multiplying rectification state, the second resonant cavity at the side A is in a voltage-multiplying rectification state, and the side B works in a half-bridge inversion state;

modality 6: switch tube Q_p3For normally on signal, the switching tube Q_p1And a switching tube Q_p2And a switching tube Q_p4And a switching tube Q_p5Realize synchronous rectification, switch tube Q_s1And a switching tube Q_s3Operating in half-bridge inverter mode, switching tube Q_s4Normally open; in the mode, the first side resonant cavity is in a full-bridge rectification state, the second side resonant cavity is in a voltage-multiplying rectification state, and the B side works in a half-bridge inversion state;

modality 7: switch tube Q_p1For normally on signal, the switching tube Q_p2And a switching tube Q_p3And a switching tube Q_p4And a switching tube Q_p5Realize synchronous rectification, switch tube Q_s1And a switching tube Q_s3Operating in half-bridge inverter mode, switching tube Q_s4Normally open; in the mode, the first side resonant cavity is in a voltage-doubling rectification state, the second side resonant cavity is in a full-bridge rectification state, and the B side works in a half-bridge inversion state;

modality 8: switch tube Q_p5For normally on signal, the switching tube Q_p1And a switching tube Q_p2And a switching tube Q_p3And a switching tube Q_p4Realize synchronous rectification, switch tube Q_s1And a switching tube Q_s3Operating in half-bridge inverter mode, switching tube Q_s4Normally open; in the mode, the first side resonant cavity is in a full-bridge rectification state, the second side resonant cavity is in a full-bridge rectification state, and the B side resonant cavity works in a half-bridge inversion state.

2. A variable/fixed bus voltage ultra-wide gain range bi-directional dc/dc converter as recited in claim 1, wherein said resonant cavity one, said resonant cavity two, and said resonant cavity three are each comprised of an inductor and a capacitor connected in series.

3. A variable/fixed bus voltage ultra-wide gain range bi-directional dc/dc converter as claimed in claim 1, wherein said filter circuit is a capacitor C connected to the output of said full-bridge rectifier circuit_B。