阅读说明：本技术 一种串并联双有源桥式变换器及调制方法 (Series-parallel connection double-active bridge converter and modulation method ) 是由 陈章勇 朱鑫彤 陈勇 陈根 冯晨晨 于 2021-01-11 设计创作，主要内容包括：本发明公开了一种串并联双有源桥式变换器及调制方法,变压器左侧通过构建两组输入并联的半桥DAB变换器模块,右侧采用串联结构,共用了一组半桥DAB变换器模块电感,减少了开关器件和元件的数量,可以实现宽范围电压输出,由于采用输入并联两个模块的设计,可以减小单个模块的电压应力,减小了设备体积尺寸。(The invention discloses a series-parallel double-active bridge converter and a modulation method, wherein two groups of half-bridge DAB converter modules with parallel inputs are constructed on the left side of a transformer, and a series structure is adopted on the right side of the transformer, so that a group of half-bridge DAB converter module inductors are shared, the quantity of switching devices and elements is reduced, wide-range voltage output can be realized, and due to the design of adopting the two modules with parallel inputs, the voltage stress of a single module can be reduced, and the volume size of equipment is reduced.)

1. A series-parallel dual active bridge converter, comprising: capacitor C₁Capacitor C₂Switch tube S₁Switch tube S₂Switch tube S₃Switch tube S₄Transformer T₁Transformer T₂Inductor L and switch tube S₅Switch tube S₆Capacitor C₃Capacitor C₄And a capacitance Co;

the switch tube S₁Respectively with the drain of the switching tube S3 and the capacitor C₁One end of the first and second switches is connected and used as a positive input end of the series-parallel double-active bridge converter; the switch tube S₁Respectively with the transformer T₁One end of the primary side and the switching tube S₂Is connected with the drain electrode of the transistor; the switch tube S₂Respectively with the switching tube S₄Source and capacitor C₂One end of the first input end is connected with the first input end and is used as a negative input end of the series-parallel double-active bridge converter; the switch tube S₃Respectively with the switching tube S₄And a transformer T₂One end of the primary side is connected; the capacitor C₁The other end of each of the first and second capacitors is connected to a capacitor C₂Another end of (1), transformer T₁The other end of the primary side and the transformer T₂The other end of the primary side is connected; the transformer T₁One end of the secondary side is connected with one end of the inductor L, and the other end of the secondary side is connected with the transformer T₂One end of the secondary side is connected(ii) a The switch tube S₅With the other end of the inductor L and the switching tube S, respectively₆Is connected with the drain electrode of the capacitor C respectively₃One end of the capacitor Co is connected with one end of the capacitor Co and is used as the positive output end of the series-parallel double-active-bridge converter; the switch tube S₆Respectively with a capacitor C₄One end of the capacitor Co is connected with the other end of the capacitor Co and is used as a negative output end of the series-parallel double-active bridge converter; the capacitor C₃The other end of each of the first and second capacitors is connected to a capacitor C₄And the other end of the transformer T₂The other end of the secondary side is connected; the switch tube S₁And a switching tube S₂Forming a first half-bridge DAB converter module; the switch tube S₃And a switching tube S₄Forming a second half-bridge DAB converter module; the switch tube S₅And a switching tube S₆Constituting a third half-bridge DAB converter module.

2. The series-parallel dual active bridge converter of claim 1, wherein there are 8 modes of the series-parallel dual active bridge converter:

the first mode is as follows: first time period t₀～t₁]In t₀At any moment, switch tube S₂Turn-off, switch tube S₁Conducting, switching tube S₄And a switching tube S₆Is kept on and passes through a switch tube S₁Current i of₁In the direction of the switching tube S₁From source to drain, through the switching tube S₄Current i of₂In the direction of the switching tube S₄Drain to source, current i of inductor L_LIs counterclockwise;

in mode one, the current i_LThe time domain expression of (a) is:t₁current value at the moment of time isWherein i_L(t₀) Is t₀Time inductor LCurrent value of (V)_oIs the output voltage of the series-parallel double active bridge converter, and t is the first time period t₀～t₁]At a time point of (1), L is the value of inductance L, T_HIs half a switching period, D₁Is a square wave voltage V of a first half-bridge DAB converter module_i1Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of D₂Square wave voltage V for second half-bridge DAB converter module_i2Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of;

mode two: second time period t₁～t₂]In t₁At any moment, switch tube S₄Turn-off, switch tube S₃Conducting, switching tube S₁And a switching tube S₆Is kept on and passes through a switch tube S₁Current i of₁In the direction of the switching tube S₁From source to drain, through the switching tube S₃Current i of₂In the direction of the switching tube S₃Source to drain, current i of inductor L_LIs counterclockwise;

in mode two, the current i_LThe time domain expression of (a) is:t₂the current value at the time is 0, wherein i_L(t₁) Is t₁Current value of time inductor L, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductance L, and t is the second time period [ t [ [ t ]₁～t₂]Time point of (1), V_oThe output voltage of the series-parallel double-active bridge converter;

mode three: third time period t₂～t₃]In t₂At any moment, switch tube S₁Switch tube S₃And a switching tube S₆Is kept on and passes through a switch tube S₁Current i of₁In the direction of the switching tube S₁From drain to source through the switching tube S₃Current i of₂Is in the direction of openingClosing pipe S₃Drain to source, current i of inductor L_LIn a clockwise direction;

in mode three, the current i_LThe time domain expression of (a) is:t₃current value at the moment of time isWherein i_L(t₂) Is t₂Current value of time inductor L, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductance L, and t is the third time period [ t₂～t₃]Time point of (1), V_oOutput voltage for series-parallel double active bridge converters, D₂Square wave voltage V for second half-bridge DAB converter module_i2Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of, T_HHalf a switching period;

and a fourth mode: fourth time period t₃～t₄]In t₃At any moment, switch tube S₆Turn-off, switch tube S₅Conducting, switching tube S₁And a switching tube S₃Is kept on and passes through a switch tube S₁Current i of₁In the direction of the switching tube S₁From drain to source through the switching tube S₃Current i of₂In the direction of the switching tube S₃Drain to source, current i of inductor L_LIn a clockwise direction;

in mode four, the current i_LThe time domain expression of (a) is:t₄current value at the moment of time isWherein i_L(t₃) Is t₃Current value of time inductor L, V_inIs the input voltage of the series-parallel double active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductance L, and t is the fourth time period [ t₃～t₄]Time point of (1), V_oFor the output voltage, T, of a series-parallel double-active-bridge converter_HIs half a switching period, D₁Is a square wave voltage V of a first half-bridge DAB converter module_i1Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of;

a fifth mode: fifth time period t₄～t₅]In t₄At any moment, switch tube S₁Turn-off, switch tube S₂Conducting, switching tube S₃And a switching tube S₅Is kept on and passes through a switch tube S₂Current i of₁In the direction of the switching tube S₂From source to drain, through the switching tube S₃Current i of₂In the direction of the switching tube S₃Drain to source, current i of inductor L_LIn a clockwise direction;

in mode five, the current i_LThe time domain expression of (a) is:t₅current value at the moment of time isWherein i_L(t₄) Is t₄Current value of time inductor L, V_oIs the output voltage of the series-parallel double-active bridge converter, and t is a fifth time period t₄～t₅]At a time point of (1), L is the value of inductance L, T_HIs half a switching period, D₁Is a square wave voltage V of a first half-bridge DAB converter module_i1Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of D₂Square wave voltage V for second half-bridge DAB converter module_i2Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of;

a sixth mode: sixth time period t₅～t₆]In t₅At any moment, switch tube S₃Turn-off, switch tube S₄Conducting, switching tube S₂And a switching tube S₅Is kept on and passes through a switch tube S₂Current i of₁In the direction of the switching tube S₂From source to drain, through the switching tube S₄Current i of₂In the direction of the switching tube S₃Source to drain, current i of inductor L_LIn a clockwise direction;

in mode six, the current i_LThe time domain expression of (a) is:t₆the current value at the time is 0, wherein i_L(t₅) Is t₅Current value of time inductor L, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductance L, and t is the sixth time period [ t₅～t₆]Time point of (1), V_oThe output voltage of the series-parallel double-active bridge converter;

a seventh mode: a seventh time period t₆～t₇]In t₆At any moment, switch tube S₂Switch tube S₄And a switching tube S₅Is kept on and passes through a switch tube S₂Current i of₁In the direction of the switching tube S₂From drain to source through the switching tube S₄Current i of₂In the direction of the switching tube S₄Drain to source, current i of inductor L_LIs counterclockwise;

in mode seven, the current i_LThe time domain expression of (a) is:t₇current value at the moment of time isWherein i_L(t₆) Is t₆Current value of time inductor L, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductance L, and t is the seventh time period [ t₆～t₇]Time point of (1), V_oOutput voltage for series-parallel double active bridge converters, D₂Square wave voltage V for second half-bridge DAB converter module_i2Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of, T_HHalf a switching period;

the mode is eight: eighth time period [ t ]₇～t₈]In t₇At any moment, switch tube S₅Turn-off, switch tube S₆Conducting, switching tube S₂And a switching tube S₄Is kept on and passes through a switch tube S₂Current i of₁In the direction of the switching tube S₂From drain to source through the switching tube S₄Current i of₂In the direction of the switching tube S₄Drain to source, current i of inductor L_LIs counterclockwise;

in mode eight, the current i_LThe time domain expression of (a) is:t₄current value at the moment of time isWherein i_L(t₇) Is t₇Current value of time inductor L, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductance L, and t is the eighth time period [ t₇～t₈]Time point of (1), V_oFor the output voltage, T, of a series-parallel double-active-bridge converter_HIs half a switching period, D₁Is a square wave voltage V of a first half-bridge DAB converter module_i1Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle.

3. A method of modulating a series-parallel double active bridge converter according to claim 1, comprising the steps of:

a1, respectively adjusting the square wave voltage V of the first half-bridge DAB converter module by taking the square wave voltage of the third half-bridge DAB converter module as a reference_i1And the square-wave voltage V of the second half-bridge DAB converter module_i2With respect to a square wave voltage V₂First leading phase shift duty cycle D₁And a second leading phase-shift duty cycle D₂；

A2, according to the adjusted first leading phase-shift duty cycle D₁And a second leading phase-shift duty cycle D₂To obtain a transformer T₁And a transformer T₂Output square wave voltage V₁；

A3 Square wave Voltage V formed from a third half bridge DAB converter Module₂Changing the voltage V across the inductance L_L，V_L＝V₁-V₂；

A4 according to the voltage V across the inductor L_LTo obtain an output voltage V_o。

4. The modulation method for series-parallel double-active bridge converter according to claim 3, wherein the output voltage V in step A4_oThe calculation formula of (2) is as follows:

wherein, T_HIs half a switching period, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductor L, R is the value of the load resistance,t_ais a square wave voltage V_i1With respect to a square wave voltage V₂Leading phase shift time of t_bIs a square wave voltage V_i2With respect to a square wave voltage V₂Advance shift ofPhase time, D₁For a first leading phase-shift duty cycle, D₂For the second leading phase shift duty cycle, set 0<D₁<1,0<D₂<1。

5. A method of modulating a series-parallel double active bridge converter according to claim 1, comprising the steps of:

b1, keeping the power output of the first half-bridge DAB converter module at maximum, i.e.Regulation of square-wave voltage V of second half-bridge DAB converter module_i2With respect to a square wave voltage V₂Second leading phase shift duty cycle D₂；

B2, according to a second leading phase-shift duty cycle D₂To obtainTo V_o,maxOutput voltage V of_oWherein V is_o,maxTo output a voltage V_oIs measured.

6. The modulation method of a series-parallel double active bridge converter according to claim 5, wherein the output voltage V in step B2_oThe calculation formula of (2) is as follows:

wherein, T_HIs half a switching period, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductor L, R is the value of the load resistance,t_bis a square wave voltage V_i2With respect to a square wave voltage V₂Advanced phase shift time of D₂A second leading phase shift duty cycle.

7. A method of modulating a series-parallel double active bridge converter according to claim 1, comprising the steps of:

c1, keeping the power output of the second half-bridge DAB converter module at maximum, i.e.Regulation of square-wave voltage V of first half-bridge DAB converter module_i1With respect to a square wave voltage V₂First leading phase shift duty cycle D₁；

C2, phase-shifting duty ratio D according to first lead₁To obtainTo V_o,maxOutput voltage V of_oWherein V is_o,maxTo output a voltage V_oIs measured.

8. The modulation method of a series-parallel double active bridge converter according to claim 7, wherein the output voltage V in step C2_oThe calculation formula of (2) is as follows:

wherein, T_HIs half a switching period, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductor L, R is the value of the load resistance,t_ais a square wave voltage V_i1With respect to a square wave voltage V₂Advanced phase shift time of D₁Is a first leading phase shift duty cycle.

9. A method of modulating a series-parallel double active bridge converter according to claim 1, comprising the steps of:

d1, turning off the first half-bridge DAB converter module, and regulating the square wave voltage V of the second half-bridge DAB converter module_i2With respect to a square wave voltage V₂Second leading phase shift duty cycle D₂；

D2, according to a second leading phase-shift duty cycle D₂To obtain 0 toOutput voltage V of_oWherein V is_o,maxTo output a voltage V_oMaximum value of (d);

the voltage V is output in the step D2_oThe calculation formula of (2) is as follows:

wherein, T_HIs half a switching period, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductor L, R is the value of the load resistance,t_bis a square wave voltage V_i2With respect to a square wave voltage V₂Advanced phase shift time of D₂A second leading phase shift duty cycle.

10. A method of modulating a series-parallel double active bridge converter according to claim 1, comprising the steps of:

e1, turning off the second half-bridge DAB converter module, and regulating the square wave voltage V of the first half-bridge DAB converter module_i1With respect to a square wave voltage V₂First leading phase shift duty cycle D₁；

E2, shifting the duty cycle D according to a first lead₁To obtain0 toOutput voltage V of_oWherein V is_o,maxTo output a voltage V_oMaximum value of (d);

the output voltage V in step E2_oThe calculation formula of (2) is as follows:

wherein, T_HIs half a switching period, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductor L, R is the value of the load resistance,t_ais a square wave voltage V_i1With respect to a square wave voltage V₂Advanced phase shift time of D₁Is a first leading phase shift duty cycle.

Technical Field

The invention relates to the field of power electronics, in particular to a series-parallel double-active bridge converter and a modulation method.

Background

With the development of modern society, Dual Active Bridge (DAB) converters have been widely used in the fields of electric vehicle charging piles, aerospace, distributed energy systems, and the like. Compared with the traditional one-way converter, the DAB converter can realize the two-way flow of energy without arranging two one-way converters, thereby greatly saving the equipment cost and space and simultaneously realizing the electrical isolation. The DAB converter has the characteristic of wide gain, can realize soft switching in a larger range, and realizes high energy efficiency and high energy density.

Disclosure of Invention

Aiming at the defects in the prior art, the series-parallel double-active bridge converter and the modulation method provided by the invention realize wide-range voltage output, can perform 'fixed adjustment and adjustment' application in specific narrow-range output scenes, and reduce the voltage stress of devices and the volume size of equipment

In order to achieve the purpose of the invention, the invention adopts the technical scheme that: a series-parallel dual active bridge converter comprising: capacitor C₁Capacitor C₂Switch tube S₁Switch tube S₂Switch tube S₃Switch tube S₄Transformer T₁Transformer T₂Inductor L and switch tube S₅Switch tube S₆Capacitor C₃Capacitor C₄And a capacitance Co;

the switch tube S₁Respectively with the drain of the switching tube S3 and the capacitor C₁One end of the first and second switches is connected and used as a positive input end of the series-parallel double-active bridge converter; the switch tube S₁Respectively with the transformer T₁One end of the primary side and the switching tube S₂Is connected with the drain electrode of the transistor; the switch tube S₂Respectively with the switching tube S₄Source and capacitor C₂One end of the first input end is connected with the first input end and is used as a negative input end of the series-parallel double-active bridge converter; the switch tube S₃Respectively with the switching tube S₄And a transformer T₂One end of the primary side is connected; the capacitor C₁The other end of each of the first and second capacitors is connected to a capacitor C₂Another end of (1), transformer T₁The other end of the primary side and the transformer T₂The other end of the primary side is connected; the transformer T₁One end of the secondary side is connected with one end of the inductor L, and the other end of the secondary side is connected with the transformer T₂One end of the secondary side is connected; the switch tube S₅With the other end of the inductor L and the switching tube S, respectively₆Is connected with the drain electrode of the capacitor C respectively₃Is connected with one end of a capacitor Co and is connected in series-parallel connectionA positive output terminal of the source bridge converter; the switch tube S₆Respectively with a capacitor C₄One end of the capacitor Co is connected with the other end of the capacitor Co and is used as a negative output end of the series-parallel double-active bridge converter; the capacitor C₃The other end of each of the first and second capacitors is connected to a capacitor C₄And the other end of the transformer T₂The other end of the secondary side is connected; the switch tube S₁And a switching tube S₂Forming a first half-bridge DAB converter module; the switch tube S₃And a switching tube S₄Forming a second half-bridge DAB converter module; the switch tube S₅And a switching tube S₆Constituting a third half-bridge DAB converter module.

Further, the series-parallel double-active bridge converter has 8 modes:

the first mode is as follows: first time period t₀～t₁]In t₀At any moment, switch tube S₂Turn-off, switch tube S₁Conducting, switching tube S₄And a switching tube S₆Is kept on and passes through a switch tube S₁Current i of₁In the direction of the switching tube S₁From source to drain, through the switching tube S₄Current i of₂In the direction of the switching tube S₄Drain to source, current i of inductor L_LIs counterclockwise;

in mode one, the current i_LThe time domain expression of (a) is:t₁current value at the moment of time isWherein i_L(t₀) Is t₀Current value of time inductor L, V_oIs the output voltage of the series-parallel double active bridge converter, and t is the first time period t₀～t₁]At a time point of (1), L is the value of inductance L, T_HIs half a switching period, D₁Is a square wave voltage V of a first half-bridge DAB converter module_i1Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of D₂Square wave voltage V for second half-bridge DAB converter module_i2Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of;

mode two: second time period t₁～t₂]In t₁At any moment, switch tube S₄Turn-off, switch tube S₃Conducting, switching tube S₁And a switching tube S₆Is kept on and passes through a switch tube S₁Current i of₁In the direction of the switching tube S₁From source to drain, through the switching tube S₃Current i of₂In the direction of the switching tube S₃Source to drain, current i of inductor L_LIs counterclockwise;

in mode two, the current i_LThe time domain expression of (a) is:t₂the current value at the time is 0, wherein i_L(t₁) Is t₁Current value of time inductor L, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductance L, and t is the second time period [ t [ [ t ]₁～t₂]Time point of (1), V_oThe output voltage of the series-parallel double-active bridge converter;

mode three: third time period t₂～t₃]In t₂At any moment, switch tube S₁Switch tube S₃And a switching tube S₆Is kept on and passes through a switch tube S₁Current i of₁In the direction of the switching tube S₁From drain to source through the switching tube S₃Current i of₂In the direction of the switching tube S₃Drain to source, current i of inductor L_LIn a clockwise direction;

in mode three, the current i_LThe time domain expression of (a) is:t₃current at time of dayHas a value ofWherein i_L(t₂) Is t₂Current value of time inductor L, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductance L, and t is the third time period [ t₂～t₃]Time point of (1), V_oOutput voltage for series-parallel double active bridge converters, D₂Square wave voltage V for second half-bridge DAB converter module_i2Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of, T_HHalf a switching period;

and a fourth mode: fourth time period t₃～t₄]In t₃At any moment, switch tube S₆Turn-off, switch tube S₅Conducting, switching tube S₁And a switching tube S₃Is kept on and passes through a switch tube S₁Current i of₁In the direction of the switching tube S₁From drain to source through the switching tube S₃Current i of₂In the direction of the switching tube S₃Drain to source, current i of inductor L_LIn a clockwise direction;

in mode four, the current i_LThe time domain expression of (a) is:t₄current value at the moment of time isWherein i_L(t₃) Is t₃Current value of time inductor L, V_inIs the input voltage of the series-parallel double active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductance L, and t is the fourth time period [ t₃～t₄]Time point of (1), V_oFor the output voltage, T, of a series-parallel double-active-bridge converter_HIs half a switching period, D₁Is a square wave voltage V of a first half-bridge DAB converter module_i1Relative to the third halfSquare wave voltage V of bridge DAB converter module₂Leading phase shift duty cycle of;

a fifth mode: fifth time period t₄～t₅]In t₄At any moment, switch tube S₁Turn-off, switch tube S₂Conducting, switching tube S₃And a switching tube S₅Is kept on and passes through a switch tube S₂Current i of₁In the direction of the switching tube S₂From source to drain, through the switching tube S₃Current i of₂In the direction of the switching tube S₃Drain to source, current i of inductor L_LIn a clockwise direction;

in mode five, the current i_LThe time domain expression of (a) is:t₅current value at the moment of time isWherein i_L(t₄) Is t₄Current value of time inductor L, V_oIs the output voltage of the series-parallel double-active bridge converter, and t is a fifth time period t₄～t₅]At a time point of (1), L is the value of inductance L, T_HIs half a switching period, D₁Is a square wave voltage V of a first half-bridge DAB converter module_i1Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of D₂Square wave voltage V for second half-bridge DAB converter module_i2Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of;

a sixth mode: sixth time period t₅～t₆]In t₅At any moment, switch tube S₃Turn-off, switch tube S₄Conducting, switching tube S₂And a switching tube S₅Is kept on and passes through a switch tube S₂Current i of₁In the direction of the switching tube S₂From source to drain, through the switching tube S₄Current i of₂In the direction of the switching tube S₃Source electrode ofCurrent i to drain, inductor L_LIn a clockwise direction;

in mode six, the current i_LThe time domain expression of (a) is:t₆the current value at the time is 0, wherein i_L(t₅) Is t₅Current value of time inductor L, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductance L, and t is the sixth time period [ t₅～t₆]Time point of (1), V_oThe output voltage of the series-parallel double-active bridge converter;

a seventh mode: a seventh time period t₆～t₇]In t₆At any moment, switch tube S₂Switch tube S₄And a switching tube S₅Is kept on and passes through a switch tube S₂Current i of₁In the direction of the switching tube S₂From drain to source through the switching tube S₄Current i of₂In the direction of the switching tube S₄Drain to source, current i of inductor L_LIs counterclockwise;

in mode seven, the current i_LThe time domain expression of (a) is:t₇current value at the moment of time isWherein i_L(t₆) Is t₆Current value of time inductor L, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductance L, and t is the seventh time period [ t₆～t₇]Time point of (1), V_oOutput voltage for series-parallel double active bridge converters, D₂Square wave voltage V for second half-bridge DAB converter module_i2Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of, T_HHalf a switching period;

the mode is eight: eighth time period [ t ]₇～t₈]In t₇At any moment, switch tube S₅Turn-off, switch tube S₆Conducting, switching tube S₂And a switching tube S₄Is kept on and passes through a switch tube S₂Current i of₁In the direction of the switching tube S₂From drain to source through the switching tube S₄Current i of₂In the direction of the switching tube S₄Drain to source, current i of inductor L_LIs counterclockwise;

in mode eight, the current i_LThe time domain expression of (a) is:t₄current value at the moment of time isWherein i_L(t₇) Is t₇Current value of time inductor L, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductance L, and t is the eighth time period [ t₇～t₈]Time point of (1), V_oFor the output voltage, T, of a series-parallel double-active-bridge converter_HIs half a switching period, D₁Is a square wave voltage V of a first half-bridge DAB converter module_i1Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of;

a modulation method of a series-parallel double-active bridge converter comprises the following steps:

a1, respectively adjusting the square wave voltage V of the first half-bridge DAB converter module by taking the square wave voltage of the third half-bridge DAB converter module as a reference_i1And the square-wave voltage V of the second half-bridge DAB converter module_i2With respect to a square wave voltage V₂First leading phase shift duty cycle D₁And a second leading phase-shift duty cycle D₂；

A2, according to the adjusted first leading phase-shift duty cycle D₁And a second leading phase-shift duty cycle D₂To obtain a transformer T₁And a transformer T₂Output square wave voltage V₁；

A3 Square wave Voltage V formed from a third half bridge DAB converter Module₂Changing the voltage V across the inductance L_L，V_L＝V₁-V₂；

A4 according to the voltage V across the inductor L_LTo obtain an output voltage V_o。

Further, the output voltage V in the step a4_oThe calculation formula of (2) is as follows:

wherein, T_HIs half a switching period, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductor L, R is the value of the load resistance,t_ais a square wave voltage V_i1With respect to a square wave voltage V₂Leading phase shift time of t_bIs a square wave voltage V_i2With respect to a square wave voltage V₂Advanced phase shift time of D₁For a first leading phase-shift duty cycle, D₂For the second leading phase shift duty cycle, set 0<D₁<1,0<D₂<1。

A modulation method of a series-parallel double-active bridge converter comprises the following steps:

b1, keeping the power output of the first half-bridge DAB converter module at maximum, i.e.Regulation of square-wave voltage V of second half-bridge DAB converter module_i2With respect to a square wave voltage V₂Second leading phase shift duty cycle D₂；

B2, according to a second leading phase-shift duty cycle D₂To obtainTo V_o,maxOutput voltage V of_oWherein V is_o,maxTo output a voltage V_oIs measured.

Further, the output voltage V in the step B2_oThe calculation formula of (2) is as follows:

wherein, T_HIs half a switching period, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductor L, R is the value of the load resistance,t_bis a square wave voltage V_i2With respect to a square wave voltage V₂Advanced phase shift time of D₂A second leading phase shift duty cycle.

A modulation method of a series-parallel double-active bridge converter comprises the following steps:

c1, keeping the power output of the second half-bridge DAB converter module at maximum, i.e.Regulation of square-wave voltage V of first half-bridge DAB converter module_i1With respect to a square wave voltage V₂First leading phase shift duty cycle D₁；

C2, phase-shifting duty ratio D according to first lead₁To obtainTo V_o,maxOutput voltage V of_oWherein V is_o,maxTo output a voltage V_oIs measured.

Further, the output voltage V in the step C2_oThe calculation formula of (2) is as follows:

wherein, T_HIs half a switching period, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductor L, R is the value of the load resistance,t_ais a square wave voltage V_i1With respect to a square wave voltage V₂Advanced phase shift time of D₁Is a first leading phase shift duty cycle.

A modulation method of a series-parallel double-active bridge converter comprises the following steps:

d1, turning off the first half-bridge DAB converter module, and regulating the square wave voltage V of the second half-bridge DAB converter module_i2With respect to a square wave voltage V₂Second leading phase shift duty cycle D₂；

D2, according to a second leading phase-shift duty cycle D₂To obtain 0 toOutput voltage V of_oWherein V is_o,maxTo output a voltage V_oMaximum value of (d);

the voltage V is output in the step D2_oThe calculation formula of (2) is as follows:

wherein, T_HIs half a switching period, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductor L, R is the value of the load resistance,t_bis a square wave voltage V_i2With respect to a square wave voltage V₂Advanced phase shift time of D₂A second leading phase shift duty cycle.

A modulation method of a series-parallel double-active bridge converter comprises the following steps:

e1, turning off the second half-bridge DAB converter module, and regulating the square wave voltage V of the first half-bridge DAB converter module_i1With respect to a square wave voltage V₂First leading phase shift duty cycle D₁；

E2, shifting the duty cycle D according to a first lead₁To obtain 0 toOutput voltage V of_oWherein V is_o,maxTo output a voltage V_oMaximum value of (d);

the output voltage V in step E2_oThe calculation formula of (2) is as follows:

wherein, T_HIs half a switching period, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductor L, R is the value of the load resistance,t_ais a square wave voltage V_i1With respect to a square wave voltage V₂Advanced phase shift time of D₁Is a first leading phase shift duty cycle.

In conclusion, the beneficial effects of the invention are as follows:

(1) a series-parallel double-active bridge converter and a modulation method are disclosed, and the structure of input parallel connection and output series connection is adopted. Two groups of half-bridge DAB converter modules with parallel inputs are constructed, the right side of the transformer adopts a series connection structure, a group of half-bridge DAB converter modules and inductors are shared, and the number of switching devices and elements is reduced. Square wave voltage V formed by right side half-bridge DAB converter module₂For reference, the two half-bridges on the left side are adjustedSquare wave voltage V formed by DAB converter module_i1And V_i2Relative to V₂Leading phase shift duty cycle D₁And D₂The output energy of the two modules can be respectively adjusted to realize the effect from 0 to V_o,maxA wider range of voltage outputs.

(2) For the convenience of control or in a specific narrow-range output scene, the output voltage can be regulated by 'regulating one at a fixed time', namely, the maximum output of one module is kept, and the output of the other module is regulated to realize the regulation of the output voltage, so that the output voltage can be regulatedTo V_o,maxA wider range of voltage outputs, or turning off one module and adjusting the output of the other module, can be achieved from 0 toA wider range of voltage outputs.

Drawings

FIG. 1 is a schematic diagram of a series-parallel dual active bridge converter;

FIG. 2 is a voltage waveform diagram of a series-parallel dual active bridge converter;

FIG. 3 is a diagram of a first mode of operation of a series-parallel dual active bridge converter;

FIG. 4 is a working mode diagram of a second mode of the series-parallel connection dual active bridge converter;

FIG. 5 is a diagram of the operation mode of a third mode of the series-parallel connection dual-active bridge converter;

fig. 6 is a working mode diagram of mode four of the series-parallel connection dual active bridge converter;

fig. 7 is a working mode diagram of mode five of the series-parallel connection dual active bridge converter;

fig. 8 is a working mode diagram of mode six of the series-parallel connection dual active bridge converter;

fig. 9 is a working mode diagram of a mode seven of the series-parallel connection dual active bridge converter;

fig. 10 is an operation mode diagram of a mode eight of the series-parallel connection dual active bridge converter;

FIG. 11 is a graph of an output gain surface;

FIG. 12 is a gain plot of the output voltage to maintain the maximum square wave voltage output by one of the half bridge DAB converter modules;

FIG. 13 is a gain plot of the output voltage with one of the half bridge DAB converter modules turned off;

FIG. 14 is a drawing showingD₂A simulated waveform at 0.22;

FIG. 15 is a drawing showingD₂A simulated waveform when 0;

FIG. 16 is a drawing showingThe simulated waveform of time.

Detailed Description

The following description of the embodiments of the present invention is provided to facilitate the understanding of the present invention by those skilled in the art, but it should be understood that the present invention is not limited to the scope of the embodiments, and it will be apparent to those skilled in the art that various changes may be made without departing from the spirit and scope of the invention as defined and defined in the appended claims, and all matters produced by the invention using the inventive concept are protected.

As shown in fig. 1, a series-parallel dual active bridge converter includes: capacitor C₁Capacitor C₂Switch tube S₁Switch tube S₂Switch tube S₃Switch tube S₄Transformer T₁Transformer T₂Inductor L and switch tube S₅Switch tube S₆Capacitor C₃Capacitor C₄And a capacitance Co;

the switch tube S₁Respectively with the drain of the switching tube S3 and the capacitor C₁One end of the first and second switches is connected and used as a positive input end of the series-parallel double-active bridge converter; the switchPipe S₁Respectively with the transformer T₁One end of the primary side and the switching tube S₂Is connected with the drain electrode of the transistor; the switch tube S₂Respectively with the switching tube S₄Source and capacitor C₂One end of the first input end is connected with the first input end and is used as a negative input end of the series-parallel double-active bridge converter; the switch tube S₃Respectively with the switching tube S₄And a transformer T₂One end of the primary side is connected; the capacitor C₁The other end of each of the first and second capacitors is connected to a capacitor C₂Another end of (1), transformer T₁The other end of the primary side and the transformer T₂The other end of the primary side is connected; the transformer T₁One end of the secondary side is connected with one end of the inductor L, and the other end of the secondary side is connected with the transformer T₂One end of the secondary side is connected; the switch tube S₅With the other end of the inductor L and the switching tube S, respectively₆Is connected with the drain electrode of the capacitor C respectively₃One end of the capacitor Co is connected with one end of the capacitor Co and is used as the positive output end of the series-parallel double-active-bridge converter; the switch tube S₆Respectively with a capacitor C₄One end of the capacitor Co is connected with the other end of the capacitor Co and is used as a negative output end of the series-parallel double-active bridge converter; the capacitor C₃The other end of each of the first and second capacitors is connected to a capacitor C₄And the other end of the transformer T₂The other end of the secondary side is connected; the switch tube S₁And a switching tube S₂Forming a first half-bridge DAB converter module; the switch tube S₃And a switching tube S₄Forming a second half-bridge DAB converter module; the switch tube S₅And a switching tube S₆Constituting a third half-bridge DAB converter module.

The series-parallel double-active bridge converter has 8 modes, and the voltage waveform is shown in figure 2 because the dead time is very short and is omitted for convenient analysis.

As shown in fig. 3, modality one: first time period t₀～t₁]In t₀At any moment, switch tube S₂Turn-off, switch tube S₁Conducting, switching tube S₄And a switching tube S₆Is kept on and passes through a switch tube S₁Current i of₁In the direction of the switching tube S₁From source to drain, through the switching tube S₄Current i of₂In the direction of the switching tube S₄Drain to source, current i of inductor L_LIs counterclockwise;

in mode one, the current i_LThe time domain expression of (a) is:t₁current value at the moment of time isWherein i_L(t₀) Is t₀Current value of time inductor L, V_oIs the output voltage of the series-parallel double active bridge converter, and t is the first time period t₀～t₁]At a time point of (1), L is the value of inductance L, T_HIs half a switching period, D₁Is a square wave voltage V of a first half-bridge DAB converter module_i1Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of D₂Square wave voltage V for second half-bridge DAB converter module_i2Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of;

as shown in fig. 4, modality two: second time period t₁～t₂]In t₁At any moment, switch tube S₄Turn-off, switch tube S₃Conducting, switching tube S₁And a switching tube S₆Is kept on and passes through a switch tube S₁Current i of₁In the direction of the switching tube S₁From source to drain, through the switching tube S₃Current i of₂In the direction of the switching tube S₃Source to drain, current i of inductor L_LIs counterclockwise;

in mode two, the current i_LThe time domain expression of (a) is:t₂the current value at the time is 0, wherein i_L(t₁) Is t₁Current value of time inductor L, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductance L, and t is the second time period [ t [ [ t ]₁～t₂]Time point of (1), V_oThe output voltage of the series-parallel double-active bridge converter;

as shown in fig. 5, modality three: third time period t₂～t₃]In t₂At any moment, switch tube S₁Switch tube S₃And a switching tube S₆Is kept on and passes through a switch tube S₁Current i of₁In the direction of the switching tube S₁From drain to source through the switching tube S₃Current i of₂In the direction of the switching tube S₃Drain to source, current i of inductor L_LIn a clockwise direction;

in mode three, the current i_LThe time domain expression of (a) is:t₃current value at the moment of time isWherein i_L(t₂) Is t₂Current value of time inductor L, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductance L, and t is the third time period [ t₂～t₃]Time point of (1), V_oOutput voltage for series-parallel double active bridge converters, D₂Square wave voltage V for second half-bridge DAB converter module_i2Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of, T_HHalf a switching period;

as shown in fig. 6, modality four: fourth time period t₃～t₄]In t₃At any moment, switch tube S₆Turn-off, switch tube S₅Conducting, switching tube S₁And a switching tube S₃Is kept on and passes through a switch tube S₁Current ofi₁In the direction of the switching tube S₁From drain to source through the switching tube S₃Current i of₂In the direction of the switching tube S₃Drain to source, current i of inductor L_LIn a clockwise direction;

in mode four, the current i_LThe time domain expression of (a) is:t₄current value at the moment of time isWherein i_L(t₃) Is t₃Current value of time inductor L, V_inIs the input voltage of the series-parallel double active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductance L, and t is the fourth time period [ t₃～t₄]Time point of (1), V_oFor the output voltage, T, of a series-parallel double-active-bridge converter_HIs half a switching period, D₁Is a square wave voltage V of a first half-bridge DAB converter module_i1Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of;

as shown in fig. 7, modality five: fifth time period t₄～t₅]In t₄At any moment, switch tube S₁Turn-off, switch tube S₂Conducting, switching tube S₃And a switching tube S₅Is kept on and passes through a switch tube S₂Current i of₁In the direction of the switching tube S₂From source to drain, through the switching tube S₃Current i of₂In the direction of the switching tube S₃Drain to source, current i of inductor L_LIn a clockwise direction;

in mode five, the current i_LThe time domain expression of (a) is:t₅current value at the moment of time isWherein i_L(t₄) Is t₄Current value of time inductor L, V_oIs the output voltage of the series-parallel double-active bridge converter, and t is a fifth time period t₄～t₅]At a time point of (1), L is the value of inductance L, T_HIs half a switching period, D₁Is a square wave voltage V of a first half-bridge DAB converter module_i1Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of D₂Square wave voltage V for second half-bridge DAB converter module_i2Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of;

as shown in fig. 8, modality six: sixth time period t₅～t₆]In t₅At any moment, switch tube S₃Turn-off, switch tube S₄Conducting, switching tube S₂And a switching tube S₅Is kept on and passes through a switch tube S₂Current i of₁In the direction of the switching tube S₂From source to drain, through the switching tube S₄Current i of₂In the direction of the switching tube S₃Source to drain, current i of inductor L_LIn a clockwise direction;

in mode six, the current i_LThe time domain expression of (a) is:t₆the current value at the time is 0, wherein i_L(t₅) Is t₅Current value of time inductor L, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductance L, and t is the sixth time period [ t₅～t₆]Time point of (1), V_oThe output voltage of the series-parallel double-active bridge converter;

as shown in fig. 9, modality seven: a seventh time period t₆～t₇]In t₆At any moment, switch tube S₂Switch tube S₄And a switching tube S₅Is kept on and passes through a switch tube S₂Current i of₁In the direction of the switching tube S₂From drain to source through the switching tube S₄Current i of₂In the direction of the switching tube S₄Drain to source, current i of inductor L_LIs counterclockwise;

in mode seven, the current i_LThe time domain expression of (a) is:t₇current value at the moment of time isWherein i_L(t₆) Is t₆Current value of time inductor L, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductance L, and t is the seventh time period [ t₆～t₇]Time point of (1), V_oOutput voltage for series-parallel double active bridge converters, D₂Square wave voltage V for second half-bridge DAB converter module_i2Square wave voltage V relative to third half-bridge DAB converter module₂Leading phase shift duty cycle of, T_HHalf a switching period;

as shown in fig. 10, modality eight: eighth time period [ t ]₇～t₈]In t₇At any moment, switch tube S₅Turn-off, switch tube S₆Conducting, switching tube S₂And a switching tube S₄Is kept on and passes through a switch tube S₂Current i of₁In the direction of the switching tube S₂From drain to source through the switching tube S₄Current i of₂In the direction of the switching tube S₄Drain to source, current i of inductor L_LIs counterclockwise;

a modulation method of a series-parallel double-active bridge converter comprises the following steps:

a1, respectively adjusting the square wave voltage V of the first half-bridge DAB converter module by taking the square wave voltage of the third half-bridge DAB converter module as a reference_i1And the square-wave voltage V of the second half-bridge DAB converter module_i2With respect to a square wave voltage V₂First leading phase shift duty cycle D₁And a second leading phase-shift duty cycle D₂；

A2, according to the adjusted first leading phase-shift duty cycle D₁And a second leading phase-shift duty cycle D₂To obtain a transformer T₁And a transformer T₂Output square wave voltage V₁；

A3 Square wave Voltage V formed from a third half bridge DAB converter Module₂Changing the voltage V across the inductance L_L，V_L＝V₁-V₂；

A4 according to the voltage V across the inductor L_LTo obtain an output voltage V_o。

The output voltage V in step A4_oThe calculation formula of (2) is as follows:

with an output gain ofThe gain surface plot is shown in FIG. 11, where T_HIs half a switching period, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductor L, R is the value of the load resistance,t_ais a square wave voltage V_i1With respect to a square wave voltage V₂Leading phase shift time of t_bIs a square wave voltage V_i2With respect to a square wave voltage V₂Advanced phase shift time of D₁For a first leading phase-shift duty cycle, D₂For the second leading phase shift duty cycle, set 0<D₁<1,0<D₂<1。

A modulation method of a series-parallel double-active bridge converter comprises the following steps:

b1, keeping output of first half bridge DAB converter moduleIs at maximum power, i.e.Regulation of square-wave voltage V of second half-bridge DAB converter module_i2With respect to a square wave voltage V₂Second leading phase shift duty cycle D₂；

B2, according to a second leading phase-shift duty cycle D₂To obtainTo V_o,maxOutput voltage V of_oWherein V is_o,maxTo output a voltage V_oIs measured.

The output voltage V in step B2_oThe calculation formula of (2) is as follows:

with an output gain ofThe output gain diagram is shown in FIG. 12, where T_HIs half a switching period, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductor L, R is the value of the load resistance,t_bis a square wave voltage V_i2With respect to a square wave voltage V₂Advanced phase shift time of D₂A second leading phase shift duty cycle.

A modulation method of a series-parallel double-active bridge converter comprises the following steps:

c1, keeping the power output of the second half-bridge DAB converter module at maximum, i.e.Regulation of square-wave voltage V of first half-bridge DAB converter module_i1With respect to square wave voltageV₂First leading phase shift duty cycle D₁；

C2, phase-shifting duty ratio D according to first lead₁To obtainTo V_o,maxOutput voltage V of_oWherein V is_o,maxTo output a voltage V_oIs measured.

The output voltage V in step C2_oThe calculation formula of (2) is as follows:

with an output gain ofThe output gain diagram is shown in FIG. 12, where T_HIs half a switching period, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductor L, R is the value of the load resistance,t_ais a square wave voltage V_i1With respect to a square wave voltage V₂Advanced phase shift time of D₁Is a first leading phase shift duty cycle.

A modulation method of a series-parallel double-active bridge converter comprises the following steps:

d1, turning off the first half-bridge DAB converter module, and regulating the square wave voltage V of the second half-bridge DAB converter module_i2With respect to a square wave voltage V₂Second leading phase shift duty cycle D₂；

D2, according to a second leading phase-shift duty cycle D₂To obtain 0 toOutput voltage V of_oWherein V is_o,maxTo output a voltage V_oMaximum value of (d);

the voltage V is output in the step D2_oThe calculation formula of (2) is as follows:

with an output gain ofThe output gain map is shown in FIG. 13, where T_HIs half a switching period, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductor L, R is the value of the load resistance,t_bis a square wave voltage V_i2With respect to a square wave voltage V₂Advanced phase shift time of D₂A second leading phase shift duty cycle.

A modulation method of a series-parallel double-active bridge converter comprises the following steps:

e1, turning off the second half-bridge DAB converter module, and regulating the square wave voltage V of the first half-bridge DAB converter module_i1With respect to a square wave voltage V₂First leading phase shift duty cycle D₁；

E2, shifting the duty cycle D according to a first lead₁To obtain 0 toOutput voltage V of_oWherein V is_o,maxTo output a voltage V_oMaximum value of (d);

the output voltage V in step E2_oThe calculation formula of (2) is as follows:

with an output gain ofThe output gain map is shown in FIG. 13, where T_HIs half a switching period, V_inIs the input voltage of the series-parallel double-active bridge converter, n is the transformation ratio of the transformer, L is the value of the inductor L, R is the value of the load resistance,t_ais a square wave voltage V_i1With respect to a square wave voltage V₂Advanced phase shift time of D₁Is a first leading phase shift duty cycle.

Simulation analysis results: the simulation parameters are as follows: input V_in100V, switching frequency 100kHz, load resistance R_L100 Ω, inductor L28 uH, and output capacitor Co 200 uF.

FIG. 14 is a schematic view of a process for producing a semiconductor deviceD₂0.22 time as the simulated waveform. Respectively an output voltage V from top to bottom_oWaveform, square wave voltage V formed by two half-bridge DAB converter modules on left side_i1And V_i2Waveform, square wave voltage V formed on right side of transformer₁Waveform, square wave voltage V formed by right-side half-bridge DAB converter₂Wave form, inductor current i_LAnd (4) waveform.

FIG. 15 is a schematic view of a process for producing a semiconductor deviceD₂The simulated waveform when 0. Respectively an output voltage V from top to bottom_oWaveform, square wave voltage V formed by two half-bridge DAB converter modules on left side_i1And V_i2Waveform, square wave voltage V formed on right side of transformer₁Waveform, square wave voltage V formed by right-side half-bridge DAB converter₂Wave form, inductor current i_LAnd (4) waveform.

FIG. 16 is a drawing showingThe simulated waveform of time. FromFrom top to bottom is the output voltage V_oWaveform, square wave voltage V formed by two half-bridge DAB converter modules on left side_i1And V_i2Waveform, square wave voltage V formed on right side of transformer₁Waveform, square wave voltage V formed by right-side half-bridge DAB converter₂Wave form, inductor current i_LAnd (4) waveform.

In conclusion, the series-parallel double-active bridge converter provided by the invention has the characteristic of wide-range output, can be used for adjusting the output of two modules simultaneously and also can be used for adjusting one at a fixed time, and the voltage stress and the volume size of a single module are reduced due to the adoption of the parallel input of the two modules.