Energy conversion apparatus, and vehicle

Abstract

Provided in the embodiments of the present application are an energy conversion apparatus, and a vehicle. The energy conversion apparatus comprises a primary-side bridge arm module, a filter module, a resonant module, a secondary-side bridge arm module and a control module, wherein the primary-side bridge arm module comprises a first bridge arm, a second bridge arm and a third bridge arm; the secondary-side bridge arm module comprises a fourth bridge arm and a fifth bridge arm; the frequency of a drive signal of the second bridge arm, the frequency of a drive signal of the third bridge arm, the frequency of a drive signal of the fourth bridge arm and the frequency of a drive signal of the fifth bridge arm are all greater than the frequency of a drive signal of the first bridge arm; and on the basis of a required gain of the energy conversion apparatus, a first sampled current, a second sampled current, a first sampled voltage and a second sampled voltage, the control module determines a phase shift angle of a target bridge arm relative to a reference bridge arm, so as to achieve soft switching actions of switches in the primary-side bridge arm module and the secondary-side bridge arm module, and realize energy control. In the embodiments of the present application, the volume and cost of the energy conversion apparatus can be reduced.

Description

Energy conversion devices and vehicles

[0001] This application claims priority to Chinese Patent Application No. 202411475163.5, filed on October 22, 2024, entitled “Energy Conversion Device and Vehicle”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of electronic circuit technology, specifically to an energy conversion device and a vehicle. Background Technology

[0003] With the development of electric vehicles, on-board chargers, as energy conversion devices for electric vehicles, have received increasing attention. These devices convert alternating current (AC) into direct current (DC) to charge the high-voltage batteries within the electric vehicle. Energy conversion devices typically employ a two-stage architecture: a power factor correction (PFC) module and a bidirectional DC / DC converter. The PFC and DC / DC modules are decoupled via electrolytic capacitors, leading to increased size and cost, and lower power density. Summary of the Invention

[0004] This application provides an energy conversion device and a vehicle that can reduce the size and cost of the energy conversion device.

[0005] A first aspect of this application provides an energy conversion device, including a primary side bridge arm module, a filtering module, a resonant module, a secondary side bridge arm module, and a control module; the primary side bridge arm module includes a first bridge arm, a second bridge arm, and a third bridge arm, and the secondary side bridge arm module includes a fourth bridge arm and a fifth bridge arm; the frequencies of the driving signals of the second bridge arm, the third bridge arm, the fourth bridge arm, and the fifth bridge arm are all greater than the frequency of the driving signal of the first bridge arm;

[0006] The first end of the filter module is connected to the first AC terminal; the second end of the filter module is connected to the midpoint of the third bridge arm and the first end of the resonant module; the third end of the filter module is connected to the midpoint of the second bridge arm and the second end of the resonant module; the midpoint of the first bridge arm is connected to the second AC terminal; the third end of the resonant module is connected to the midpoint of the fourth bridge arm; the fourth end of the resonant module is connected to the midpoint of the fifth bridge arm; the first end of the first bridge arm is connected to the first end of the second bridge arm and the first end of the third bridge arm; the second end of the first bridge arm is connected to the second end of the second bridge arm and the second end of the third bridge arm; the first end of the fourth bridge arm is connected to the first end of the fifth bridge arm and the first DC terminal; the second end of the fourth bridge arm is connected to the second end of the fifth bridge arm and the second DC terminal.

[0007] The control module determines the phase shift angle of the target bridge arm relative to the reference bridge arm based on the required gain of the energy conversion device, the first sampling current, the second sampling current, the first sampling voltage, and the second sampling voltage, so as to realize the soft switching action of the switches in the primary bridge arm module and the secondary bridge arm module.

[0008] Wherein, the reference bridge arm is one of the second bridge arm, the third bridge arm, the fourth bridge arm, and the fifth bridge arm, and the target bridge arm is the bridge arm other than the reference bridge arm among the second bridge arm, the third bridge arm, the fourth bridge arm, and the fifth bridge arm; the phase shift angle of the target bridge arm relative to the reference bridge arm is used to control the timing of the drive signal of the target bridge arm; the first sampling current is the sampling current at the first end of the filter module; the second sampling current is the sampling current between the second end of the fifth bridge arm and the second DC end; the first sampling voltage is the sampling voltage between the first AC end and the second AC end or the sampling voltage between the first end of the third bridge arm and the second end of the third bridge arm; and the second sampling voltage is the sampling voltage between the first DC end and the second DC end.

[0009] Optionally, the resonant module includes: a resonant inductor, a first resonant capacitor, a second resonant capacitor, and a transformer;

[0010] The resonant inductor and the first resonant capacitor are connected in series with the primary winding of the transformer, and the second resonant capacitor is connected in series with the secondary winding of the transformer.

[0011] Optionally, the filtering module includes a first inductor and a second inductor, with a first end of the first inductor connected to a first end of the second inductor and the first AC terminal, a second end of the first inductor connected to the midpoint of the third bridge arm, and a second end of the second inductor connected to the midpoint of the second bridge arm.

[0012] Optionally, the filtering module includes a coupling inductor, a first end of which is connected to a second end of which is connected to a first AC terminal, a third end of which is connected to the midpoint of the third bridge arm, and a fourth end of which is connected to the midpoint of the second bridge arm.

[0013] Optionally, the energy conversion device further includes a first filter capacitor, a second filter capacitor, and a third filter capacitor. The two ends of the first filter capacitor are respectively connected to the first AC terminal and the second AC terminal. The two ends of the second filter capacitor are respectively connected to the first end of the third bridge arm and the second end of the third bridge arm. The two ends of the third filter capacitor are respectively connected to the first end of the fifth bridge arm and the second end of the fifth bridge arm.

[0014] Optionally, the control module determines the phase shift angle of the target bridge arm relative to the reference bridge arm based on the required gain of the energy conversion device, the first sampling current, the second sampling current, the first sampling voltage, and the second sampling voltage, including:

[0015] The control module determines the phase shift angle between the first voltage waveform and the second voltage waveform based on the first sampling current, the second sampling current, the first sampling voltage, and the second sampling voltage. The first voltage waveform is the voltage waveform between the midpoint of the third bridge arm and the midpoint of the second bridge arm, and the second voltage waveform is the voltage waveform between the midpoint of the fourth bridge arm and the midpoint of the fifth bridge arm.

[0016] The control module determines the phase shift angle of the target bridge arm relative to the reference bridge arm based on the phase shift angle between the first voltage waveform and the second voltage waveform, the required gain of the energy conversion device, the turns ratio of the transformer, the first sampling voltage, and the second sampling voltage.

[0017] Optionally, the control module includes: a phase-locked loop, a first current control loop, a second current control loop, a voltage control loop, a multiplier, a small-value module, and a phase-shifting modulation module;

[0018] The phase-locked loop is used to perform loop calculation on the first sampled voltage and output the first loop calculation result;

[0019] The second current control loop is used to perform loop calculation on the result of subtracting the second sampled current and the first reference current, and output the second loop calculation result;

[0020] The voltage control loop is used to perform loop calculation on the result of subtracting the second sampled voltage and the second reference voltage, and output the third loop calculation result.

[0021] The minimum value module is used to take the minimum value between the second loop calculation result and the third loop calculation result;

[0022] The multiplier is used to multiply the minimum value of the second loop calculation result and the third loop calculation result with the first loop calculation result to obtain the second reference current;

[0023] The first current control loop is used to perform loop calculations on the result of subtracting the second reference current and the first sampling current, and output the phase shift angle between the first voltage waveform and the second voltage waveform.

[0024] The phase-shift modulation module is used to determine the phase shift angle of the target bridge arm relative to the reference bridge arm based on the phase shift angle between the first voltage waveform and the second voltage waveform, the required gain of the energy conversion device, the turns ratio of the transformer, the first sampling voltage, and the second sampling voltage.

[0025] Optionally, when the reference bridge arm is the third bridge arm and the target bridge arm includes the second bridge arm, the fourth bridge arm, and the fifth bridge arm, the phase shift angle of the second bridge arm relative to the third bridge arm, the phase shift angle of the fourth bridge arm relative to the third bridge arm, and the phase shift angle of the fifth bridge arm relative to the third bridge arm are determined according to the following formula:

[0026] When the required gain of the energy conversion device is less than 1, D p =(1-D y1 ); D s1 =(1-D y1 -D α1 ); D s2 =(1-D y1 -D α1 ); D α1 =(1-D y1 +2D Φ ) / 2; If D Φ <D ΦB Then D y1 =k×(2D) Φ +1) / (2-k); If D Φ ≥D ΦB Then D y1 =[2×D Φ [×(1-k)+2k-1] / k; D ΦB = (1-k) / 2, k = Ge;

[0027] Ge is the required gain of the energy conversion device, and D is... Φ D is the phase shift angle between the first voltage waveform and the second voltage waveform. pD is the phase shift angle of the second bridge arm relative to the third bridge arm. s1 D is the phase shift angle of the fourth bridge arm relative to the third bridge arm. s2 The phase shift angle of the fifth bridge arm relative to the third bridge arm.

[0028] Optionally, if the required gain of the energy conversion device is greater than or equal to 1, D p =0; D s1 =D α2 -(1-D y2 ); D s2 =D α2 D α2 =(1-D y2 +2D Φ ) / 2; If D Φ <D ΦB Then D y2 =k×(2D) Φ +1) / (2-k); If D Φ ≥D ΦB Then D y2 =[2×D Φ [×(1-k)+2k-1] / k; D ΦB = (1-k) / 2, k = 1 / Ge;

[0029] Ge is the required gain of the energy conversion device, and D is... Φ D is the phase shift angle between the first voltage waveform and the second voltage waveform. p D is the phase shift angle of the second bridge arm relative to the third bridge arm. s1 D is the phase shift angle of the fourth bridge arm relative to the third bridge arm. s2 The phase shift angle of the fifth bridge arm relative to the third bridge arm.

[0030] A second aspect of this application provides a vehicle including an energy conversion device and a battery, as described in the first aspect of this application. The energy conversion device is used to convert alternating current (AC) into direct current (DC) to charge the battery.

[0031] Compared to a two-stage architecture using a PFC module and a DC / DC module, the energy conversion device of this application embodiment can use fewer bridge arms, thereby reducing the size and cost of the energy conversion device. The control module can determine the phase shift angle of the target bridge arm relative to the reference bridge arm based on the required gain of the energy conversion device, the first sampling current, the second sampling current, the first sampling voltage, and the second sampling voltage. This enables soft-switching of the switches in the primary and secondary bridge arm modules, reducing switching losses and thus improving the conversion efficiency of the energy conversion device. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 is a schematic diagram of an energy conversion device provided in an embodiment of this application;

[0034] Figure 2 is a schematic diagram of another energy conversion device provided in an embodiment of this application;

[0035] Figure 3 is a schematic diagram of the specific control structure of an energy conversion device provided in an embodiment of this application;

[0036] Figure 4 is a schematic diagram of the specific control structure of another energy conversion device provided in an embodiment of this application;

[0037] Figure 5 is a schematic diagram of the specific control structure of another energy conversion device provided in the embodiment of this application;

[0038] Figure 6 is a schematic diagram of the specific control structure of another energy conversion device provided in an embodiment of this application;

[0039] Figure 7 is a flowchart illustrating a control method based on an energy conversion device provided in an embodiment of this application;

[0040] Figure 8 shows a V frequency within one power frequency cycle provided in an embodiment of this application. ac V Bus V AB V CD andi p A waveform diagram;

[0041] Figures 9 to 12 show the drive signals and V signals of each switch when Ge < 1, as provided in the embodiments of this application. AB V CD and i p A waveform diagram;

[0042] Figures 13 to 15 show the drive signals and V signals of each switch when Ge>1, according to an embodiment of this application. AB V CD and i p A waveform diagram;

[0043] Figure 16 is an embodiment of the present application that uses a PFC module, a DC / DC module, and an energy conversion device;

[0044] Figure 17 is a structural schematic diagram of a vehicle provided in an embodiment of this application. Detailed Implementation

[0045] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0046] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, system, product, or apparatus that comprises a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, products, or apparatuses.

[0047] In this application, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.

[0048] Please refer to Figure 1, which is a schematic diagram of an energy conversion device provided in an embodiment of this application. As shown in Figure 1, the energy conversion device may include a filter module 10, a primary side bridge arm module 20, a resonant module 30, a secondary side bridge arm module 40, and a control module 50; the primary side bridge arm module 20 includes a first bridge arm, a second bridge arm, and a third bridge arm, and the secondary side bridge arm module 40 includes a fourth bridge arm and a fifth bridge arm; the frequencies of the driving signals of the second bridge arm, the third bridge arm, the fourth bridge arm, and the fifth bridge arm are all greater than the frequency of the driving signal of the first bridge arm;

[0049] The first end of the filter module 10 is connected to the first AC terminal; the second end of the filter module 10 is connected to the midpoint of the third bridge arm and the first end of the resonant module 30; the third end of the filter module 10 is connected to the midpoint of the second bridge arm and the second end of the resonant module 30; the midpoint of the first bridge arm is connected to the second AC terminal; the third end of the resonant module 30 is connected to the midpoint of the fourth bridge arm; the fourth end of the resonant module 30 is connected to the midpoint of the fifth bridge arm; the first end of the first bridge arm is connected to the first end of the second bridge arm and the first end of the third bridge arm; the second end of the first bridge arm is connected to the second end of the second bridge arm and the second end of the third bridge arm; the first end of the fourth bridge arm is connected to the first end of the fifth bridge arm and the first DC terminal; the second end of the fourth bridge arm is connected to the second end of the fifth bridge arm and the second DC terminal.

[0050] The control module 50 determines the phase shift angle of the target bridge arm relative to the reference bridge arm based on the required gain of the energy conversion device, the first sampling current, the second sampling current, the first sampling voltage, and the second sampling voltage, so as to realize the soft switching action of the switches in the primary side bridge arm module 20 and the secondary side bridge arm module 40.

[0051] Wherein, the reference bridge arm is one of the second bridge arm, the third bridge arm, the fourth bridge arm, and the fifth bridge arm, and the target bridge arm is the bridge arm other than the reference bridge arm among the second bridge arm, the third bridge arm, the fourth bridge arm, and the fifth bridge arm; the phase shift angle of the target bridge arm relative to the reference bridge arm is used to control the timing of the drive signal of the target bridge arm; the first sampling current is the sampling current at the first terminal of the filter module 10; the second sampling current is the sampling current between the second terminal of the fifth bridge arm and the second DC terminal; the first sampling voltage is the sampling voltage between the first AC terminal and the second AC terminal or the sampling voltage between the first terminal of the third bridge arm and the second terminal of the third bridge arm; and the second sampling voltage is the sampling voltage between the first DC terminal and the second DC terminal.

[0052] As shown in Figure 1, the first bridge arm includes a first switch S1 and a second switch S2. The first end of the first switch S1 is connected to the first end of the first bridge arm, and the second end of the first switch S1 is connected to the first end of the second switch S2 and the midpoint of the first bridge arm. The second end of the second switch S2 is connected to the second end of the first bridge arm. The driving signal for the first bridge arm includes a first driving signal and a second driving signal. The control module 50 can control the driving module to send a first driving signal to the third end of the first switch S1, which is used to control the first switch S1 to be on or off. The control module 50 can also control the driving module to send a second driving signal to the third end of the second switch S2, which is used to control the second switch S2 to be on or off. The frequency of the first driving signal is the same as the frequency of the second driving signal. The first driving signal and the second driving signal are complementary signals; that is, within one cycle of the first driving signal, one of the first switches S1 and the second switch S2 is on, and the other is off. For example, the duty cycle of both the first driving signal and the second driving signal is 50% (ignoring dead time). For example, the frequencies of the first drive signal and the second drive signal are the grid frequency, which can also be called the power frequency. For instance, the grid frequency can be 50 Hz.

[0053] As shown in Figure 1, the second bridge arm includes a third switch S3 and a fourth switch S4. The first end of the third switch S3 is connected to the first end of the second bridge arm, the second end of the third switch S3 is connected to the first end of the fourth switch S4 and the midpoint of the second bridge arm, and the second end of the fourth switch S4 is connected to the second end of the second bridge arm. The driving signals for the second bridge arm include the third driving signal and the fourth driving signal. The control module 50 can control the driving module to send a third driving signal to the third end of the third switch S3, which is used to control the conduction or deactivation of the third switch S3; the control module 50 can also control the driving module to send a fourth driving signal to the third end of the fourth switch S4, which is used to control the conduction or deactivation of the fourth switch S4. The frequencies of the third driving signal and the fourth driving signal are the same, and the third driving signal and the fourth driving signal are complementary signals, that is, within one cycle of the third driving signal, one of the third switch S3 and the fourth switch S4 is on, and the other is off. For example, the duty cycle of both the third driving signal and the fourth driving signal is 50% (ignoring dead time). The frequencies of the third and fourth drive signals are the switching frequencies. For example, the switching frequency can be 50 kHz.

[0054] As shown in Figure 1, the third bridge arm includes a fifth switch S5 and a sixth switch S6. The first end of the fifth switch S5 is connected to the first end of the third bridge arm, the second end of the fifth switch S5 is connected to the first end of the sixth switch S6 and the midpoint of the third bridge arm, and the second end of the sixth switch S6 is connected to the second end of the third bridge arm. The driving signals for the third bridge arm include the fifth driving signal and the sixth driving signal. The control module 50 can control the driving module to send the fifth driving signal to the third end of the fifth switch S5, which is used to control the conduction or deactivation of the fifth switch S5; the control module 50 can also control the driving module to send the sixth driving signal to the third end of the sixth switch S6, which is used to control the conduction or deactivation of the sixth switch S6. The frequencies of the fifth driving signal and the sixth driving signal are the same, and the fifth driving signal and the sixth driving signal are complementary signals, that is, within one cycle of the fifth driving signal, one of the fifth switch S5 and the sixth switch S6 is on, and the other is off. For example, the duty cycle of both the fifth driving signal and the sixth driving signal is 50% (ignoring dead time). The frequencies of the fifth and sixth drive signals are the switching frequencies. For example, the switching frequency can be 50kHz.

[0055] As shown in Figure 1, the fourth bridge arm includes a seventh switch S7 and an eighth switch S8. The first end of the seventh switch S7 is connected to the first end of the fourth bridge arm, the second end of the seventh switch S7 is connected to the first end of the eighth switch S8 and the midpoint of the fourth bridge arm, and the second end of the eighth switch S8 is connected to the second end of the fourth bridge arm. The driving signals for the fourth bridge arm include the seventh driving signal and the eighth driving signal. The control module 50 can control the driving module to send the seventh driving signal to the third end of the seventh switch S7, which is used to control the seventh switch S7 to be turned on or off; the control module 50 can also control the driving module to send the eighth driving signal to the third end of the eighth switch S8, which is used to control the eighth switch S8 to be turned on or off. The seventh driving signal and the eighth driving signal have the same frequency and are complementary signals, that is, within one cycle of the seventh driving signal, one of the seventh switch S7 and the eighth switch S8 is on and the other is off. For example, the duty cycle of both the seventh and eighth drive signals is 50% (ignoring dead time). The frequencies of the seventh and eighth drive signals are the switching frequencies. For example, the switching frequency can be 50kHz.

[0056] As shown in Figure 1, the fifth bridge arm includes a ninth switch S9 and a tenth switch S10. The first end of the ninth switch S9 is connected to the first end of the fifth bridge arm, and the second end of the ninth switch S9 is connected to the first end of the tenth switch S10 and the midpoint of the fifth bridge arm. The second end of the tenth switch S10 is connected to the second end of the fifth bridge arm. The driving signals for the fifth bridge arm include the ninth driving signal and the tenth driving signal. The control module 50 can control the driving module to send the ninth driving signal to the third end of the ninth switch S9, which is used to control the ninth switch S9 to be turned on or off. The control module 50 can also control the driving module to send the tenth driving signal to the third end of the tenth switch S10, which is used to control the tenth switch S10 to be turned on or off. The frequencies of the ninth driving signal and the tenth driving signal are the same, and the ninth driving signal and the tenth driving signal are complementary signals. That is, within one cycle of the ninth driving signal, one of the ninth switch S9 and the tenth switch S10 is on, and the other is off. For example, the duty cycle of both the ninth and tenth drive signals is 50% (ignoring dead time). The frequencies of the ninth and tenth drive signals are the switching frequencies. For example, the switching frequency can be 50kHz.

[0057] As shown in Figure 1, the switches in the primary side bridge arm module 20 include: first switch S1, second switch S2, third switch S3, fourth switch S4, fifth switch S5, and sixth switch S6. The switches in the secondary side bridge arm module 40 include seventh switch S7, eighth switch S8, ninth switch S9, and tenth switch S10.

[0058] In this diagram, switches S1, S2, S3, S4, S5, S6, S7, S8, S9, and S10 can be either Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) or Insulated-Gate Bipolar Transistors (IGBTs). MOSFETs are also called MOS transistors or MOS tubes. The switches in Figure 1 are all examples of N-type MOS transistors, which can be simply referred to as NOMS transistors. MOSFETs can be silicon carbide (SiC) MOSFETs or gallium nitride (GaN) MOSFETs. Silicon carbide MOSFETs are MOSFETs made of silicon carbide, and gallium nitride MOSFETs are MOSFETs made of gallium nitride.

[0059] The phase shift angle of the target bridge arm relative to the reference bridge arm refers to the phase difference between the starting position of the drive signal of the target bridge arm in one cycle and the starting position of the drive signal of the reference bridge arm in one cycle.

[0060] Soft switching introduces resonance before and after the switch turns off and on, enabling the switch to achieve zero-voltage switching (i.e., the voltage across the switch drops to zero before the switch turns on); or enabling the switch to achieve zero-current switching (i.e., the current in the switch drops to zero before the switch turns off). This eliminates the overlap of voltage and current during the switching process, reduces the rate of change of voltage and current, significantly reduces or even eliminates switching losses, and also significantly reduces switching noise.

[0061] In one possible embodiment, the energy conversion device can perform the function of alternating current to direct current (AC / DC). In this case, the first AC terminal and the second AC terminal serve as AC input terminals, and the first DC terminal and the second DC terminal serve as DC output terminals, allowing the energy conversion device to convert the input AC to the output DC.

[0062] In one possible embodiment, the energy conversion device can perform the function of direct current to alternating current (DC / AC). In this case, the first AC terminal and the second AC terminal serve as AC output terminals, and the first DC terminal and the second DC terminal serve as DC input terminals, allowing the energy conversion device to convert the input DC into AC output.

[0063] For example, the energy conversion device could be an on-board charger in a vehicle. The on-board charger could be a bidirectional on-board charger, capable of both AC to DC conversion and DC to AC conversion.

[0064] Compared to a two-stage architecture using a PFC module and a DC / DC module, the energy conversion device of this application embodiment can use fewer bridge arms and eliminates the need for electrolytic capacitors, thereby reducing the size and cost of the energy conversion device. The control module 50 can determine the phase shift angle of the target bridge arm relative to the reference bridge arm based on the required gain of the energy conversion device, the first sampling current, the second sampling current, the first sampling voltage, and the second sampling voltage. This enables soft-switching of the switches in the primary-side bridge arm module 20 and the secondary-side bridge arm module 40, reducing switching losses and thus improving the conversion efficiency of the energy conversion device.

[0065] Optionally, the resonant module 30 includes: a resonant inductor L r First resonant capacitor C rp Second resonant capacitor C rsand transformer Tr. The resonant inductor L r and the first resonant capacitor C rp The second resonant capacitor C is connected in series with the primary winding of the transformer Tr. rs It is connected in series with the secondary winding of the transformer Tr.

[0066] The first end of the primary winding of the transformer Tr and the magnetizing inductance L m The first end is connected, and the second end of the primary winding of the transformer Tr is connected to the magnetizing inductor L. m The second end.

[0067] The primary winding of the transformer Tr can integrate a magnetizing inductor, or the magnetizing inductor can be independent of the primary winding. Figure 1 illustrates this with the magnetizing inductor being independent of the primary winding.

[0068] As shown in Figure 1, the resonant inductor L r The first end is connected to the midpoint of the third bridge arm, and the resonant inductor L r The second terminal is connected to the first terminal of the primary winding of the transformer Tr and the magnetizing inductor L. m The first terminal, and the second terminal of the primary winding of the transformer Tr, are connected to the magnetizing inductor L. m The second end and the first resonant capacitor C rp The first end, the first resonant capacitor C rp The second end of the transformer Tr is connected to the midpoint of the second bridge arm; the first end of the secondary winding of the transformer Tr is connected to the midpoint of the fourth bridge arm, and the second end of the secondary winding of the transformer Tr is connected to the second resonant capacitor C. rs The first terminal, the second resonant capacitor C rs The second end is connected to the midpoint of the fifth bridge arm.

[0069] It should be noted that the connection method in the resonant module 30 of Figure 1 is one possible connection method. Resonant inductor L r First resonant capacitor C rp It can be arbitrarily connected in series with the primary winding of transformer Tr (e.g., resonant inductor L). r With the first resonant capacitor C rp After being connected in series, it is connected between the midpoint of the third bridge arm and the first end of the primary winding of the transformer Tr; for example, the resonant inductor L r With the first resonant capacitor C rp After being connected in series, it is connected between the midpoint of the second bridge arm and the second end of the primary winding of the transformer Tr; for example, the resonant inductor L r The first resonant capacitor C is connected in series between the midpoint of the third bridge arm and the first end of the primary winding of the transformer Tr.rp It is connected in series between the midpoint of the second bridge arm and the second end of the primary winding of the transformer Tr; for example, the first resonant capacitor C rp The resonant inductance L is connected in series between the midpoint of the third bridge arm and the first end of the primary winding of the transformer Tr. r The second resonant capacitor C is connected in series between the midpoint of the second bridge arm and the second end of the primary winding of the transformer Tr. rs It can be arbitrarily connected in series with the secondary winding of transformer Tr, and the embodiments of this application are not limited thereto (for example, the second resonant capacitor C). rs It is connected in series between the first end of the secondary winding of transformer Tr and the midpoint of the fourth bridge arm; another example is the second resonant capacitor C. rs It is connected in series between the second end of the secondary winding of transformer Tr and the midpoint of the fifth bridge arm.

[0070] Among them, the frequencies of the second, third, fourth, and fifth bridge arms are switching frequencies, which are greater than the resonant frequency of the resonant module 30.

[0071] Optionally, as shown in Figure 1, the filtering module 10 includes a first inductor L1 and a second inductor L2. The first end of the first inductor L1 is connected to the first end of the second inductor L2 and the first AC terminal. The second end of the first inductor L1 is connected to the midpoint of the third bridge arm. The second end of the second inductor L2 is connected to the midpoint of the second bridge arm.

[0072] Among them, the first inductor L1 and the second inductor L2 are AC side inductors, which provide filtering and energy storage functions.

[0073] Optionally, as shown in Figure 2, the filter module 10 includes a coupling inductor, the first end of which is connected to the second end of the coupling inductor and the first AC terminal, the third end of which is connected to the midpoint of the third bridge arm, and the fourth end of which is connected to the midpoint of the second bridge arm.

[0074] In this embodiment, a coupled inductor is used, which can integrate the first inductor L1 and the second inductor L2 in Figure 1 into a single inductor L, reducing the volume of the filter module 10 and thus the volume of the energy conversion device, thereby reducing costs and increasing the power density of the energy conversion device.

[0075] Optionally, as shown in Figure 1 or Figure 2, the energy conversion device further includes a first filter capacitor C1, a second filter capacitor C2, and a third filter capacitor C3. The two ends of the first filter capacitor C1 are respectively connected to the first AC terminal and the second AC terminal. The two ends of the second filter capacitor C2 are respectively connected to the first end of the third bridge arm and the second end of the third bridge arm. The two ends of the third filter capacitor C3 are respectively connected to the first end of the fifth bridge arm and the second end of the fifth bridge arm.

[0076] The first filter capacitor C1 is the AC-side filter capacitor, the second filter capacitor C2 is the primary-side high-frequency filter capacitor, used to absorb high-frequency ripple from the switch. The third filter capacitor C3 is the DC-side high-frequency filter capacitor, used to absorb high-frequency ripple.

[0077] Optionally, the control module 50 determines the phase shift angle of the target bridge arm relative to the reference bridge arm based on the required gain of the energy conversion device, the first sampling current, the second sampling current, the first sampling voltage, and the second sampling voltage, including:

[0078] The control module 50 determines the phase shift angle between the first voltage waveform and the second voltage waveform based on the first sampling current, the second sampling current, the first sampling voltage, and the second sampling voltage. The first voltage waveform is the voltage waveform between the midpoint of the third bridge arm and the midpoint of the second bridge arm, and the second voltage waveform is the voltage waveform between the midpoint of the fourth bridge arm and the midpoint of the fifth bridge arm.

[0079] The control module 50 determines the phase shift angle of the target bridge arm relative to the reference bridge arm based on the phase shift angle between the first voltage waveform and the second voltage waveform, the required gain of the energy conversion device, the turns ratio of the transformer Tr, the first sampling voltage, and the second sampling voltage.

[0080] As shown in Figure 1 or Figure 2, the voltage between the midpoint B of the second bridge arm and the midpoint A of the third bridge arm is V. AB The voltage between the midpoint C of the fourth bridge arm and the midpoint D of the fifth bridge arm is V. CD The first voltage waveform is V. AB The waveform, the second voltage waveform is V CD The waveform.

[0081] The phase shift angle between the first and second voltage waveforms refers to the phase shift angle of the second voltage waveform relative to the first voltage waveform, i.e., V. CD Compared to V AB The phase difference between the high-level center lines of one cycle. For example, as shown in Figures 10 to 15, the first voltage waveform V AB Second voltage waveform V CD The phase shift angle between them is DΦ V CD Compared to V AB In one cycle (T) s The time difference between the high-level center lines is D. Φ ×T s / 2.

[0082] Please refer to Figure 3, which is a schematic diagram of the specific control structure of an energy conversion device provided in an embodiment of this application. Figure 3 is derived from Figure 1. As shown in Figure 3, based on Figure 1, the control module 50 includes: a phase-locked loop, a first current control loop, a second current control loop, a voltage control loop, a multiplier, a small-scale module, and a phase-shift modulation module. The energy conversion device in Figure 3 is used to convert the input AC to DC output.

[0083] The phase-locked loop is used to sample the first voltage (V as shown in Figure 3). ac_FB Perform loop calculations and output the first loop calculation result. First sampled voltage V ac_FB This is the sampling voltage between the first AC terminal and the second AC terminal. The first sampling voltage V... ac_FB The voltage is obtained through sampling using the AC voltage sampling module shown in Figure 3. The AC voltage sampling module is used to sample the voltage between the first AC terminal and the second AC terminal.

[0084] The second current control loop is used to control the second sampling current (as shown in Figure 3, I). HV_FB ) and the first reference current (I as shown in Figure 3) HV_Ref The result of the subtraction operation is used for loop calculation, and the second loop calculation result is output. Among them, the first reference current I... HV_Ref This is the current output demand current currently set by the energy conversion device, and the second sampling current I. HV_FB The current is obtained through sampling by the output current sampling module in Figure 3. The output current sampling module is used to sample the current between the second end and the second DC end of the fifth bridge arm. The current between the second end and the second DC end of the fifth bridge arm can be a filtered current (for example, the filtered current after passing through the third filter capacitor C3 in Figure 3).

[0085] The voltage control loop is used to control the second sampled voltage (V as shown in Figure 3). HV_FB ) and the second reference voltage (V as shown in Figure 3) HV_Ref The result of the subtraction operation is used for loop calculation, and the third loop calculation result is output. Among them, the second reference voltage V... HV_Ref This is the current output demand voltage set by the energy conversion device, and the second sampling voltage V. HV_FBThe voltage is obtained through sampling by the output voltage sampling module shown in Figure 3. The output voltage sampling module is used to sample the voltage between the first DC terminal and the second DC terminal.

[0086] The minimum value module is used to take the minimum value between the second loop calculation result and the third loop calculation result.

[0087] The multiplier is used to multiply the minimum value of the second loop calculation result and the third loop calculation result with the first loop calculation result to obtain the second reference current (i as shown in Figure 3). ac_Ref ).

[0088] The first current control loop is used to control the second reference current i ac_Ref and the first sampling current (as shown in Figure 3 I) ac_FB The result of the subtraction operation (i.e., i) ac_Ref -I ac_FB Perform loop calculations and output the phase shift angle between the first and second voltage waveforms (as shown in Figure 3, D). Φ ). I ac_FB The current is obtained by sampling through the AC current module in Figure 3. The AC current module is used to sample the current at the first end of the filter module.

[0089] Please refer to Figure 4, which is a schematic diagram of the specific control structure of another energy conversion device provided in this application embodiment. As shown in Figure 4, the first sampling current can be the sampling current on the first inductor L1 (as shown in Figure 4). L1_FB ) and the sampling current on the second inductor L2 (as shown in Figure 4 I) L2_FB The sum of ) I L1_FB The current is obtained by sampling through AC current module 1 in Figure 4, I. L2_FB The current is obtained by sampling through AC current module 2 in Figure 4. AC current module 1 is used to sample the current flowing through the first inductor L1, and AC current module 2 is used to sample the current flowing through the second inductor L2.

[0090] In Figures 3 and 4, the first sampling voltage is the sampling voltage between the first AC terminal and the second AC terminal.

[0091] In Figures 5 and 6, compared to Figures 3 and 4, the first sampling voltage is the sampling voltage between the first end and the second end of the third bridge arm, i.e., the voltage across the second filter capacitor C2. As shown in Figures 5 and 6, the Bus voltage sampling module is used to sample the voltage V across the second filter capacitor C2. Bus_FB The resonant current sampling module is used to sample the resonant inductor L. r current i p .

[0092] The phase-shift modulation module is used to adjust the phase shift angle D between the first voltage waveform and the second voltage waveform. Φ The required gain Ge of the energy conversion device, the turns ratio n of the transformer Tr, and the first sampling voltage (V as shown in Figure 3 or Figure 4) ac_FB Or as shown in Figure 5 or Figure 6, V Bus_FB ), the second sampling voltage V HV_FB Determine the phase shift angle of the target bridge arm relative to the reference bridge arm.

[0093] In Figure 3, the PWM signal generation module is a pulse width modulation (PWM) module. The PWM signal generation module can generate the signal generation signal of each switch according to the phase shift angle of the target bridge arm relative to the reference bridge arm. The drive module amplifies and isolates the signal generation signal of each switch to generate the drive signal of each switch. The drive signal of the switch is used to drive the switch to turn on or off.

[0094] When implementing the AC / DC function in Figure 3, V in Figure 3... ac The AC input power supply is from the mains grid. The first filter capacitor C1 is the AC input filter capacitor; the first inductor L1 and the second inductor L2 are the AC input inductors, providing filtering and energy storage functions. In Figure 3, the first switch S1 and the second switch S2 operate according to the mains grid frequency (e.g., 50Hz). The first bridge arm formed by the first switch S1 and the second switch S2 is called the slow bridge arm; the second bridge arm formed by the third switch S3 and the fourth switch S4, and the third bridge arm formed by the fifth switch S5 and the sixth switch S6, are called the fast bridge arms, operating according to the switching frequency. The voltage at the midpoint A of the third bridge arm and the midpoint B of the second bridge arm is called V. AB The second filter capacitor C2 is a high-frequency filter capacitor on the primary side, used to absorb high-frequency ripple from the switch. Resonant inductor L... r With the first resonant capacitor C rp and the second resonant capacitor C rs To form a resonant circuit, the magnetizing inductance L m Let n be the magnetizing inductance of transformer Tr, and n:1 be the electrical insulation and voltage ratio conversion provided by transformer Tr for the primary and secondary sides. The fourth bridge arm consists of switches S7 and S8, and the fifth bridge arm consists of switches S9 and S10. The fourth and fifth bridge arms are also called fast bridge arms and operate according to the switching frequency. The voltage between the midpoint C of the fourth bridge arm and the midpoint D of the fifth bridge arm is V. CD The third filter capacitor, C3, is the output high-frequency filter capacitor, used to absorb high-frequency ripple.

[0095] In the energy conversion device shown in Figure 3, the control module 50 can employ dual-loop control. To meet the constant voltage and constant current charging requirements of the energy conversion device, the second current control loop and the voltage control loop in the control module 50 engage in competitive control, taking the minimum value of their outputs to determine the reference current of the first current control loop (i.e., the second reference current i). ac_Ref The first current control loop is used to control the first sampled current I. ac_FB and the first sampling voltage V ac_FB For tracking control, the output of the first current control loop is used to determine the midpoint voltage V of the primary bridge arm (which includes the second and third bridge arms) and the secondary bridge arm (which includes the fourth and fifth bridge arms). AB and V CD The phase shift angle D between Φ For ease of control, the third bridge arm (fifth switch S5 and sixth switch S6) is used as a reference. If the phase shift angle (or phase shift time) of the second bridge arm (third switch S3 and fourth switch S4) relative to the third bridge arm is defined as D... p The phase shift angle (or phase shift time) of the fourth bridge arm (seventh switch S7 and eighth switch S8) relative to the third bridge arm is D. S1 The phase shift angle (or phase shift time) of the fifth bridge arm (the ninth switch S9 and the tenth switch S10) relative to the third bridge arm is D. S2 Finally, the phase-shifting modulation module controls the output D based on the first current. Φ The first sampling voltage V ac_FB The second sampling voltage V HV_FB D is determined by the turns ratio n of transformer Tr. p D s1 and D s2 The value is then used to generate a wave signal through the PWM wave generation module of the control module 50, and a drive signal for each switch is generated through the drive module, thereby controlling the third switch S3, the fourth switch S4, the fifth switch S5, the sixth switch S6, the seventh switch S7, the eighth switch S8, the ninth switch S9 and the tenth switch S10.

[0096] Based on the energy conversion device shown in Figure 3, 4, 5, or 6, this application provides a control method based on the energy conversion device. Please refer to Figure 7, which is a flowchart illustrating a control method based on the energy conversion device provided in this application. As shown in Figure 7, the control method based on the energy conversion device includes the following steps:

[0097] 701, the control module determines the phase shift angle between the first voltage waveform and the second voltage waveform based on the first sampling current, the second sampling current, the first sampling voltage, and the second sampling voltage. The first voltage waveform is the voltage waveform between the midpoint of the third bridge arm and the midpoint of the second bridge arm, and the second voltage waveform is the voltage waveform between the midpoint of the fourth bridge arm and the midpoint of the fifth bridge arm.

[0098] Wherein, the first sampling current is the sampling current at the first end of the filter module 10, the second sampling current is the sampling current between the second end of the fifth bridge arm and the second DC end, the first sampling voltage is the sampling voltage between the first AC end and the second AC end (as shown in Figures 3 and 4) or the sampling voltage between the first end of the third bridge arm and the second end of the third bridge arm (as shown in Figures 5 and 6), and the second sampling voltage is the sampling voltage between the first DC end and the second DC end.

[0099] Step 701 can be executed by the phase-locked loop, the first current control loop, the second current control loop, the voltage control loop, the multiplier, and the small-scale module in the control module of the energy conversion device shown in Figure 3, Figure 4, Figure 5, or Figure 6.

[0100] Specifically, in Figures 3 to 6, the AC voltage sampling module samples the voltage between the first AC terminal and the second AC terminal to obtain the first sampling voltage V. ac_FB The phase-locked loop (PLL) measures the first sampled voltage V. ac_FB Perform loop calculations and output the first loop calculation result. The output current sampling module samples the current between the second terminal and the second DC terminal of the fifth bridge arm to obtain the second sampling current I. HV_FB The second current control loop controls the second sampling current I. HV_FB and the first reference current I HV_Ref The result of the subtraction operation is used for loop calculation, and the second loop calculation result is output. Among them, the first reference current I... HV_Ref This is the current output demand current currently set by the energy conversion device. The output voltage sampling module samples the voltage between the first DC terminal and the second DC terminal. The voltage control loop controls the second sampled voltage V. HV_FB Second reference voltage V HV_Ref The result of the subtraction operation is used for loop calculation, and the third loop calculation result is output. Among them, the second reference voltage V... HV_Ref This is the currently set output voltage requirement of the energy conversion device. The small module takes the minimum value between the second loop calculation result and the third loop calculation result. The multiplier multiplies the minimum value between the second loop calculation result and the third loop calculation result with the first loop calculation result to obtain the second reference current i. ac_Ref The first current control loop in Figure 3 or Figure 5 controls the second reference current i. ac_Ref and the first sampling current Iac_FB The result after subtraction (i.e., i) ac_Ref -I ac_FB Perform loop calculations and output the first voltage waveform V. AB Second voltage waveform V CD The phase shift angle D between Φ In Figure 3 or Figure 5, the AC current module samples the current at the first terminal of the filter module, i.e., the first sampling current I. ac_FB .

[0101] The first current control loop in Figure 4 or Figure 6 controls the second reference current i. ac_Ref and the first sampling current I ac_FB The result after subtraction (i.e., i) ac_Ref -I ac_FB Perform loop calculations and output the first voltage waveform V. AB Second voltage waveform V CD The phase shift angle D between Φ In Figure 4 or Figure 6, the AC current module samples the current flowing through the first inductor L1 to obtain the I... L1_FB The AC current module 2 in Figure 4 or Figure 6 is used to sample the current flowing through the second inductor L2 to obtain I. L2_FB The first sampling current is I. L1_FB and I L2_FB The sum of these, i.e., the first sampling current I ac_FB =I L1_FB +I L2_FB .

[0102] 702, the control module determines the phase shift angle of the target bridge arm relative to the reference bridge arm based on the phase shift angle between the first voltage waveform and the second voltage waveform, the required gain of the energy conversion device, the turns ratio of the transformer, the first sampling voltage, and the second sampling voltage.

[0103] The required gain of the energy conversion device is defined as: Ge = n × V CD / V AB , where n is the turns ratio of transformer Tr (i.e., the turns ratio of the primary winding to the secondary winding of transformer Tr). V AB The first voltage waveform, V CD This is the second voltage waveform.

[0104] Step 702 can be executed through the phase-shift modulation module in the control module. The control strategy of the phase-shift modulation module is shown in Figure 8. First, the first voltage waveform V is output by the first current control loop. AB Second voltage waveform V CD The phase shift angle D between ΦNext, the variables needed in the phase-shifting algorithm are calculated, where k is an intermediate variable determined by Ge. ΦB D Φ The boundary condition. After the relevant variables are calculated, the equivalent duty cycle D of the original side bridge arm is calculated according to whether Ge is greater than 1. y1 Equivalent duty cycle D of the secondary side bridge arm y2 And finally determine the phase shift angles of the other three bridge arms relative to the reference bridge arm: D p D s1 and D s2 .

[0105] For example, when the reference bridge arm is the third bridge arm and the target bridge arm includes the second bridge arm, the fourth bridge arm, and the fifth bridge arm, the phase shift angle of the second bridge arm relative to the third bridge arm, the phase shift angle of the fourth bridge arm relative to the third bridge arm, and the phase shift angle of the fifth bridge arm relative to the third bridge arm are determined according to the following formula:

[0106] When the required gain of the energy conversion device is less than 1, D p =(1-D y1 ); D s1 =(1-D y1 -D α1 ); D s2 =(1-D y1 -D α1 ); D α1 =(1-D y1 +2D Φ ) / 2; If D Φ <D ΦB Then D y1 =k×(2D) Φ +1) / (2-k); If D Φ ≥D ΦB Then D y1 =[2×D Φ [×(1-k)+2k-1] / k; D ΦB = (1-k) / 2, k = Ge;

[0107] When the required gain of the energy conversion device is greater than or equal to 1, D p =0; D s1 =D α2 -(1-D y2 ); D s2 =D α2 D α2 =(1-D y2 +2D Φ ) / 2; If D Φ <DΦB Then D y2 =k×(2D) Φ +1) / (2-k); If D Φ ≥D ΦB Then D y2 =[2×D Φ [×(1-k)+2k-1] / k; D ΦB = (1-k) / 2, k = 1 / Ge;

[0108] Where Ge is the required gain of the energy conversion device, and D Φ D is the phase shift angle between the first voltage waveform and the second voltage waveform. p D is the phase shift angle of the second bridge arm relative to the third bridge arm. s1 D is the phase shift angle of the fourth bridge arm relative to the third bridge arm. s2 The phase shift angle of the fifth bridge arm relative to the third bridge arm.

[0109] To illustrate the control strategy and control effect of the embodiments of this application in more detail, Figure 9 shows a power frequency cycle (as shown in Figure 9, T). line AC voltage V input inside) ac The voltage V of the second filter capacitor C2 Bus The first voltage waveform V AB The second voltage waveform V CD and the primary current waveform i of transformer Tr p V ac i represents the voltage between the first AC terminal and the second AC terminal in Figure 3, 4, 5, or 6. p The resonant inductor L in Figure 3, 4, 5, or 6 r The current. As can be seen from Figure 9, the control strategy adopted in this embodiment can effectively achieve power factor value and power transmission control. It should be noted that the power frequency period T line It must be greater than the switching period T. s .

[0110] Figures 10-15 show typical timing waveforms of six different modulation methods for switches based on the control strategy of this application embodiment, distinguishing between Ge<1 (i.e., the energy conversion device operates in buck mode) and Ge>1 (i.e., the energy conversion device operates in boost mode). By applying the control strategy, soft-switching operation under different output voltages and loads can be achieved, thereby improving the efficiency of the energy conversion device. In Figures 10-15, the horizontal axis represents time, and the vertical axis represents the amplitude of the waveform. During the time period when the waveform of the switch's drive signal is 0 on the vertical axis, the switch is off; during the time period when the waveform of the switch's drive signal is greater than 0 on the vertical axis, the switch is on (for example, when the waveform of the drive signal of the fifth switch S5 is 0 on the vertical axis, it indicates that the fifth switch S5 is off; when the waveform of the drive signal of the fifth switch S5 is greater than 0 on the vertical axis, it indicates that the fifth switch S5 is on). Ge is the required gain of the energy conversion device, D... Φ D is the phase shift angle between the first and second voltage waveforms. p D is the phase shift angle of the second bridge arm relative to the third bridge arm. s1 D is the phase shift angle of the fourth bridge arm relative to the third bridge arm. s2 V is the phase shift angle of the fifth bridge arm relative to the third bridge arm. AB The first voltage waveform, V CD This is the second voltage waveform. p The resonant inductor L in Figure 3, 4, 5, or 6 r The current on, T s For the switching cycle. V ac V represents the voltage value between the first AC terminal and the second AC terminal in Figure 3, 4, 5, or 6. HV The voltage value between the first DC terminal and the second DC terminal in Figure 3.

[0111] Figures 10-12 show three typical control waveforms when Ge < 1. For convenience, the dead time is ignored. The dashed lines in the figures represent the switching action moments. Taking half a switching cycle of the fifth switch S5 as an example, it can be seen that during the positive half-cycle of the switching frequency of the fifth switch S5, i p When the value is negative, the corresponding zero-voltage switch (ZVS) of the primary-side switch is turned on, i p When i is positive, the corresponding ZVS of the secondary switch is turned on. Conversely, during the negative half-cycle of the switching frequency, i p When the value is negative, the ZVS of the corresponding secondary switch is turned on, i p When it is positive, the ZVS of the primary-side switch is turned on. In Figure 10, Ge < 1, D P =0,D S1 =D S2 >0. In Figure 11, Ge < 1, 0 < D. P <DS1 =D S2 In Figure 12, Ge < 1, D P >D S1 =D S2 >0.

[0112] Figures 13-15 show three typical control waveforms when Ge>1. For convenience, the dead time is ignored. The dashed lines in the figures represent the switching action moments. Taking half a switching cycle of the fifth switch S5 as an example, it can be seen that during the positive half-cycle of the switching frequency of the fifth switch S5, i p When it is negative, the ZVS of the corresponding primary-side switch is turned on, i p When i is positive, the corresponding ZVS of the secondary switch is turned on. Conversely, during the negative half-cycle of the switching frequency, i p When the value is negative, the ZVS of the corresponding secondary switch is turned on, i p When it is positive, the ZVS of the primary-side switch is turned on. In Figure 13, Ge>1, D P =0,D S1 =D S2 >0. In Figure 14, Ge>1, D P =0,D S2 >D S1 >0. In Figure 15, Ge>1, D P =0,D S1 <0,D S2 >0.

[0113] It should be noted that in Figures 10 to 15, V AB With V in Figures 5 and 6 Bus_FB Same, V CD V in Figures 3, 4, 5 and 6 HV_FB same.

[0114] The primary side switch refers to the switch in the primary side bridge arm module 20 (e.g., the third switch S3, the fourth switch S4, the fifth switch S5, and the sixth switch S6), and the secondary side switch refers to the switch in the secondary side bridge arm module 40 (the seventh switch S7, the eighth switch S8, the ninth switch S9, and the tenth switch S10).

[0115] In this embodiment, to achieve power factor correction on the AC side, a dual active bridge (DAB) control strategy is incorporated into the modulation strategy. The primary and secondary switches of transformer Tr are modulated with a 50% duty cycle, respectively. Power factor correction and power transmission control are achieved through phase shifting of the primary and secondary sides, resulting in simple control, easy implementation, and fast system response. Furthermore, to reduce switching losses and improve efficiency, the switching frequency f should be designed... sThe frequency is greater than the resonant frequency. At the same time, when Ge < 1, the phase shift between the primary side bridge arms can be increased, and when Ge > 1, the phase shift between the secondary side bridge arms can be increased, thereby further reducing the switching loss.

[0116] The topology shown in Figures 3, 4, 5, or 6 is simple, cost-effective, and extends the lifespan of the energy conversion device, saving users operating costs. Figure 8 features a simple control strategy that uses algorithms to flexibly configure soft-switching actions under different output voltages and load conditions, improving the energy conversion efficiency and electromagnetic interference (EMI) characteristics of the energy conversion device.

[0117] Please refer to Figure 16, which illustrates an energy conversion device employing a PFC module and a DC / DC module according to an embodiment of this application. Figure 16 shows a traditional two-stage architecture topology, requiring a large electrolytic capacitor (as shown in Figure 16) to be placed between the PFC module and the DC / DC module. bus Compared to Figure 16, Figure 1 or Figure 2 is a single-stage topology. The single-stage topology of Figure 1 or Figure 2 not only eliminates the need for electrolytic capacitors, but also reduces the total number of switches, which can further optimize the cost of the energy conversion device and improve its reliability.

[0118] Please refer to Figure 17, which is a structural schematic diagram of a vehicle provided in an embodiment of this application. As shown in Figure 17, the vehicle may include an energy conversion device 100 and a battery 200. The battery 200 may be a power battery in the vehicle. The vehicle may be an electric vehicle. The energy conversion device 100 can be used to convert alternating current (AC) to direct current (DC) to charge the battery 200. The battery 200 can input DC power into the energy conversion device 100, and the energy conversion device 100 converts the input DC power into AC power to supply AC loads.

[0119] The specific structure and working principle of the energy conversion device 100 in Figure 17 can be found in the embodiments shown in Figures 1 to 6 above, and will not be repeated here.

[0120] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0121] In the several embodiments provided in this application, it should be understood that the disclosed energy conversion device and vehicle can be implemented in other ways. For example, the energy conversion device embodiments described above are merely illustrative. For instance, the division of the units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed.

Claims

1. An energy conversion device, characterized in that, It includes a filtering module, a primary-side bridge arm module, a resonant module, a secondary-side bridge arm module, and a control module; the primary-side bridge arm module includes a first bridge arm, a second bridge arm, and a third bridge arm, and the secondary-side bridge arm module includes a fourth bridge arm and a fifth bridge arm; the frequencies of the driving signals of the second bridge arm, the third bridge arm, the fourth bridge arm, and the fifth bridge arm are all greater than the frequency of the driving signal of the first bridge arm; The first end of the filter module is connected to the first AC terminal; the second end of the filter module is connected to the midpoint of the third bridge arm and the first end of the resonant module; the third end of the filter module is connected to the midpoint of the second bridge arm and the second end of the resonant module; the midpoint of the first bridge arm is connected to the second AC terminal; the third end of the resonant module is connected to the midpoint of the fourth bridge arm; the fourth end of the resonant module is connected to the midpoint of the fifth bridge arm; the first end of the first bridge arm is connected to the first end of the second bridge arm and the first end of the third bridge arm; the second end of the first bridge arm is connected to the second end of the second bridge arm and the second end of the third bridge arm; the first end of the fourth bridge arm is connected to the first end of the fifth bridge arm and the first DC terminal; the second end of the fourth bridge arm is connected to the second end of the fifth bridge arm and the second DC terminal. The control module determines the phase shift angle of the target bridge arm relative to the reference bridge arm based on the required gain of the energy conversion device, the first sampling current, the second sampling current, the first sampling voltage, and the second sampling voltage, so as to realize the soft switching action of the switches in the primary bridge arm module and the secondary bridge arm module. Wherein, the reference bridge arm is one of the second bridge arm, the third bridge arm, the fourth bridge arm, and the fifth bridge arm, and the target bridge arm is the bridge arm other than the reference bridge arm among the second bridge arm, the third bridge arm, the fourth bridge arm, and the fifth bridge arm; the phase shift angle of the target bridge arm relative to the reference bridge arm is used to control the timing of the drive signal of the target bridge arm; the first sampling current is the sampling current at the first end of the filter module; the second sampling current is the sampling current between the second end of the fifth bridge arm and the second DC end; the first sampling voltage is the sampling voltage between the first AC end and the second AC end or the sampling voltage between the first end of the third bridge arm and the second end of the third bridge arm; and the second sampling voltage is the sampling voltage between the first DC end and the second DC end.

2. The energy conversion device according to claim 1, characterized in that, The resonant module includes: a resonant inductor, a first resonant capacitor, a second resonant capacitor, and a transformer; The resonant inductor and the first resonant capacitor are connected in series with the primary winding of the transformer, and the second resonant capacitor is connected in series with the secondary winding of the transformer.

3. The energy conversion device according to claim 1, characterized in that, The filtering module includes a first inductor and a second inductor. The first end of the first inductor is connected to the first end of the second inductor and the first AC terminal. The second end of the first inductor is connected to the midpoint of the third bridge arm. The second end of the second inductor is connected to the midpoint of the second bridge arm.

4. The energy conversion device according to claim 1, characterized in that, The filtering module includes a coupling inductor, the first end of which is connected to the second end of the coupling inductor and the first AC terminal, the third end of which is connected to the midpoint of the third bridge arm, and the fourth end of which is connected to the midpoint of the second bridge arm.

5. The energy conversion device according to any one of claims 1 to 4, characterized in that, The energy conversion device further includes a first filter capacitor, a second filter capacitor, and a third filter capacitor. The two ends of the first filter capacitor are respectively connected to the first AC terminal and the second AC terminal. The two ends of the second filter capacitor are respectively connected to the first end of the third bridge arm and the second end of the third bridge arm. The two ends of the third filter capacitor are respectively connected to the first end of the fifth bridge arm and the second end of the fifth bridge arm.

6. The energy conversion device according to claim 2, characterized in that, The control module determines the phase shift angle of the target bridge arm relative to the reference bridge arm based on the required gain of the energy conversion device, the first sampling current, the second sampling current, the first sampling voltage, and the second sampling voltage, including: The control module determines the phase shift angle between the first voltage waveform and the second voltage waveform based on the first sampling current, the second sampling current, the first sampling voltage, and the second sampling voltage. The first voltage waveform is the voltage waveform between the midpoint of the third bridge arm and the midpoint of the second bridge arm, and the second voltage waveform is the voltage waveform between the midpoint of the fourth bridge arm and the midpoint of the fifth bridge arm. The control module determines the phase shift angle of the target bridge arm relative to the reference bridge arm based on the phase shift angle between the first voltage waveform and the second voltage waveform, the required gain of the energy conversion device, the turns ratio of the transformer, the first sampling voltage, and the second sampling voltage.

7. The energy conversion device according to claim 6, characterized in that, The control module includes: a phase-locked loop, a first current control loop, a second current control loop, a voltage control loop, a multiplier, a small-value module, and a phase-shifting modulation module; The phase-locked loop is used to perform loop calculation on the first sampled voltage and output the first loop calculation result; The second current control loop is used to perform loop calculation on the result of subtracting the second sampled current and the first reference current, and output the second loop calculation result; The voltage control loop is used to perform loop calculation on the result of subtracting the second sampled voltage and the second reference voltage, and output the third loop calculation result. The minimum value module is used to take the minimum value between the second loop calculation result and the third loop calculation result; The multiplier is used to multiply the minimum value of the second loop calculation result and the third loop calculation result with the first loop calculation result to obtain the second reference current; The first current control loop is used to perform loop calculations on the result of subtracting the second reference current and the first sampling current, and output the phase shift angle between the first voltage waveform and the second voltage waveform. The phase-shift modulation module is used to determine the phase shift angle of the target bridge arm relative to the reference bridge arm based on the phase shift angle between the first voltage waveform and the second voltage waveform, the required gain of the energy conversion device, the turns ratio of the transformer, the first sampling voltage, and the second sampling voltage.

8. The energy conversion device according to claim 6 or 7, characterized in that, When the reference bridge arm is the third bridge arm, and the target bridge arm includes the second bridge arm, the fourth bridge arm, and the fifth bridge arm, the phase shift angle of the second bridge arm relative to the third bridge arm, the phase shift angle of the fourth bridge arm relative to the third bridge arm, and the phase shift angle of the fifth bridge arm relative to the third bridge arm are determined according to the following formula: When the required gain of the energy conversion device is less than 1 D p =(1-D y1 );D s1 =(1-D y1 -D α1 );D s2 =(1-D y1 -D α1 );D α1 =(1-D y1 +2D Φ ) / 2; If D Φ <D ΦB Then D y1 =k×(2D) Φ +1) / (2-k); If D Φ ≥D ΦB Then D y1 =[2×D Φ [×(1-k)+2k-1] / k; D ΦB =(1-k) / 2,k=Ge; Ge is the required gain of the energy conversion device, and D is... Φ D is the phase shift angle between the first voltage waveform and the second voltage waveform. p D is the phase shift angle of the second bridge arm relative to the third bridge arm. s1 D is the phase shift angle of the fourth bridge arm relative to the third bridge arm. s2 The phase shift angle of the fifth bridge arm relative to the third bridge arm.

9. The energy conversion device according to claim 8, characterized in that, When the required gain of the energy conversion device is greater than or equal to 1 D p =0;D s1 =D α2 -(1-D y2 );D s2 =D α2 ;D α2 =(1-D y2 +2D Φ ) / 2; If D Φ <D ΦB Then D y2 =k×(2D) Φ +1) / (2-k); If D Φ ≥D ΦB Then D y2 =[2×D Φ [×(1-k)+2k-1] / k; D ΦB =(1-k) / 2,k=1 / Ge; Ge is the required gain of the energy conversion device, and D is... Φ D is the phase shift angle between the first voltage waveform and the second voltage waveform. p D is the phase shift angle of the second bridge arm relative to the third bridge arm. s1 D is the phase shift angle of the fourth bridge arm relative to the third bridge arm. s2 The phase shift angle of the fifth bridge arm relative to the third bridge arm.

10. A vehicle, characterized in that, Includes the energy conversion device and battery as described in any one of claims 1 to 9, wherein the energy conversion device is used to convert alternating current into direct current to charge the battery.

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