WO2021016742A1

WO2021016742A1 - Voltage converter

Info

Publication number: WO2021016742A1
Application number: PCT/CN2019/097915
Authority: WO
Inventors: Kuenfaat YUEN; Tinho LI; Kai TIAN; Mei Liang
Original assignee: Abb Schweiz Ag
Priority date: 2019-07-26
Filing date: 2019-07-26
Publication date: 2021-02-04

Abstract

Embodiments of present disclosure relates to a converter. The converter comprises a first conversion unit, a second conversion unit, a switching circuit and a controller. The first conversion unit includes a first voltage source and a second voltage source, and is configured to generate a first voltage from an input voltage. The second conversion unit includes a third voltage source and a fourth voltage source, and is configured to generate a second voltage from the input voltage. The switching circuit is coupled to the first and second conversion units. The controller is coupled to the switching circuit, and is configured to in response to receiving an indication of voltage, cause the switching circuit to couple the first and second conversion units in parallel or in series, cause the first and second voltage sources in series or in parallel, and cause the third and fourth voltage sources in series or in parallel to generate a output voltage.

Description

VOLTAGE CONVERTER

TECHNICAL FIELD

Example embodiments of the present disclosure generally relate to an electrical apparatus and more particularly, to a voltage converter circuit and an apparatus including the voltage converter circuit.

BACKGROUND

Voltage conversion is widely employed in various applications. For example, an electric vehicle (EV) charging apparatus converts a voltage of main supply into a charging voltage, and it generally requires a higher and higher charging voltage to increase charging power. In some cases, the voltage may be up to 1000V, and the voltage range for charging thus may be from less than 200V to 1000V.

To output such a wide voltage range, conventional topologies, such as the single LLC topology and the phase shift topology, need to sacrifice their power efficiencies significantly, because they are working in a condition which is more far away from its optimal operation point under the wide output voltage range regulation.

As an alternative, a modular configuration has been proposed to balance between efficiency and voltage range. CN204538972U describes such an approach. However, the voltage range for the proposed topology is still limited, especially in consideration of efficiency.

SUMMARY

Example embodiments of the present disclosure propose a solution of a voltage converter.

In a first aspect, it is provided a converter. The converter comprises a first conversion unit, a second conversion unit, a switching circuit and a controller. The first conversion unit includes a first voltage source and a second voltage source, and is configured to generate a first voltage from an input voltage. The second conversion unit includes a third voltage source and a fourth voltage source, and is configured to generate a second voltage from the input voltage. The switching circuit is coupled to the first and second conversion units. The controller is coupled to the switching circuit, and is configured to in response to receiving an indication of voltage, cause the switching circuit to couple the first and second conversion units in parallel or in series, cause the first and second voltage sources in series or in parallel, and cause the third and fourth voltage sources in series or in parallel to generate a output voltage.

In a second aspect, it is provided an electronic device. The electronic device comprises an AC-DC converter and a converter of the first aspect. The converter is coupled to the AC-DC converter and configured to convert a first DC voltage from the AC-DC converter into a second DC voltage.

In a third aspect, it is provided a method for manufacturing a converter. The method comprises providing a first conversion unit including a first voltage source and a second voltage source and configured to generate a first voltage from an input voltage; providing a second conversion unit including a third voltage source and a fourth voltage source and configured to generate a second voltage from the input voltage; coupling a switching circuit to the first and second conversion units; and coupling a controller to the switching circuit. The controller is configured to in response to receiving an indication of voltage, cause the switching circuit to couple the first and second conversion units in parallel or in series, cause the first and second voltage sources in series or in parallel, and cause the third and fourth voltage sources in series or in parallel to generate a output voltage.

According to the embodiments of the present disclosure, the converter according to embodiments of the present disclosure may achieve a desirable efficiency based on the proposed topology.

BRIEF DESCRIPTION OF THE DRAWINGS

Through the following detailed descriptions with reference to the accompanying drawings, the above and other objectives, features and advantages of the example embodiments disclosed herein will become more comprehensible. In the drawings, several example embodiments disclosed herein will be illustrated in an example and in a non-limiting manner, wherein:

Fig. 1 illustrates an AC-DC electric charging system in accordance with some example embodiments of the present disclosure;

Fig. 2 illustrates an example of an electric device in accordance with some example embodiments of the present disclosure;

Fig. 3 illustrates an example of a schematic circuit of the electric device of Fig. 2 in accordance with some example embodiments of the present disclosure;

Fig. 4 illustrates an example of an equivalent circuit of the DC-DC converter of Fig. 3 in accordance with some example embodiments of the present disclosure; and

Fig. 5 illustrates an example of a method for manufacturing a converter in accordance with some example embodiments of the present disclosure.

Throughout the drawings, the same or corresponding reference symbols refer to the same or corresponding parts.

DETAILED DESCRIPTION

The subject matter described herein will now be discussed with reference to several example embodiments. These embodiments are discussed only for the purpose of enabling those skilled persons in the art to better understand and thus implement the subject matter described herein, rather than suggesting any limitations on the scope of the subject matter.

The term “comprises” or “includes” and its variants are to be read as open terms that mean “includes, but is not limited to. ” The term “or” is to be read as “and/or” unless the context clearly indicates otherwise. The term “based on” is to be read as “based at least in part on. ” The term “being operable to” is to mean a function, an action, a motion or a state can be achieved by an operation induced by a user or an external mechanism. The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment. ” The term “another embodiment” is to be read as “at least one other embodiment. ”

Unless specified or limited otherwise, the terms “mounted, ” “connected, ” “supported, ” and “coupled” and variations thereof are used broadly and encompass direct and indirect mountings, connections, supports, and couplings. Furthermore, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings. In the description below, like reference numerals and labels are used to describe the same, similar or corresponding parts in the Figures. Other definitions, explicit and implicit, may be included below.

Unless specified or limited otherwise, the terms “resistor” , “capacitor” , “inductor” , “switch” and other electrical elements may include one or more element that has the same function and operates together to achieve the function. For example, a resistor may refer to two or more resistors connected in serial or in parallel to function as one resistor. It is to be understood that completely turning-on or turning-off are directed to duty cycles of 100%or 0%for a switch.

As mentioned above, conventional topologies usually have a limited voltage range, especially in consideration of conversion efficiency, and the application may be thus limited.

Fig. 1 illustrates an AC-DC electric charging system 100 in accordance with some example embodiments of the present disclosure. The electric system 100 includes an AC source 2 outputting an AC voltage, an electronic device 10 for converting the AC voltage into a DC voltage, and an electronic vehicle 4 for receiving the DC power. Although the electronic vehicle 4 is illustrated, this is only for illustration without suggesting any limitations as to the scope of the subject matter described here. For example, the embodiments disclosed herein may be applied to other environments, such as power transmission.

Fig. 2 illustrates an example of electronic device 10 in accordance with some example embodiments of the present disclosure. The converter 10 includes an AC-DC converter 14 configured to convert an AC voltage into a DC voltage, and a DC-DC converter 16 including a controller 12 and configured to convert the DC voltage from the AC-DC converter 14 into a different DC voltage.

Although the DC converter 16 is illustrated to include the controller 12, this is only for illustration without suggesting any limitations as to the scope of the subject matter described here. For example, the controller 12 may be provided in the AC-DC converter 14 and coupled to the DC-DC converter 14 to control its operation and/or the AC-DC converter’s operation. Alternatively, the controller 12 may be provided independently and coupled to the DC-DC converter 14 to control its operation and/or the AC-DC converter’s operation. In another embodiment, the controller 12 may include various controlling units located at different locations to perform different controlling functions.

Although the electronic device 10 is illustrated to include the AC-DC converter 14, this is only for illustration without suggesting any limitations as to the scope of the subject matter described here. In case that the electronic device 10 is coupled to a DC source, the AC-DC converter 14 may be omitted.

Fig. 3 illustrates an example of a schematic circuit of the electric device of Fig. 2 in accordance with some example embodiments of the present disclosure. The electric device 10 includes the controller 12, the AC-DC converter 14 and the DC-DC converter 16.

The controller 12 is not illustrated to couple to elements in the DC-DC converter 16 and/or the AC-DC converter 14 for not blurring other connections. However, it is appreciated that the controller 12 is coupled to elements, such as switches, in the DC-DC converter 16 and/or the AC-DC converter 14 to control their operation. In addition, the controller 12 may couple to other components in some embodiments. For example, the controller 12 may couple to the AC source 2 to control its output.

The AC-DC converter 14 may include two sets of conversion circuits. The first set includes three H-bridges B1, B2 and B3 for the three phases respectively. The second set includes three H-bridges B4, B5 and B6 for the three phases respectively. Since the H-bridges may have the same structure, only the H-bridge B1 will be described for brevity.

The H-bridge B1 includes four switches S11, S12, S13 and S4, and is configured to switch in an optimized fixed frequency. The three H-bridges have a 120 degree phase difference therebetween to convert the AC input Vin into a DC voltage. The H-bridge B1 is coupled to a LLC stage including the capacitor C0 and the primary winding of the transformer Tx1. The secondary winding of the transformer Tx1 is configured to generate a DC current to charge the capacitors C1 and C2. In an example, the switches S11, S12, S13 and S4 may be IGBTs.

The capacitors C1 and C2 receive currents from the secondary windings of the transformers Tx1, Tx2 and Tx3. Similarly, the capacitors C3 and C4 receive currents from the secondary windings of the transformers Tx4, Tx5 and Tx6.

With the three-phase rectifying configuration of Fig. 3, the high frequency ripple from LLC to the capacitors may be very small. As such, less expensive capacitor may be applied for LLC.

The DC-DC converter 16 includes two conversion units generating the converted voltage across an output capacitor Cout. Although the output capacitor Cout is illustrated, this is only for illustration without suggesting any limitations as to the scope of the subject matter described here. For example, the output voltage may be directly applied to a load, such as an electric vehicle.

The details of configuration and operation of the DC-DC converter 16 will be described hereinafter with respect to Fig. 4. Fig. 4 illustrates an example of an equivalent circuit of the DC-DC converter 16 of Fig. 3 in accordance with some example embodiments of the present disclosure.

The configuration of Fig. 3 can be equaled to the schematic circuit of Fig. 4. The capacitors C1, C2, C3 and C4 of Fig. 3 can be functionally equaled to the DC voltage source VS1, VS2, VS3 and VS4 of Fig. 4.

In Fig. 4, the first conversion unit CU1 includes a first branch including the first voltage source VS1 and a first diode D1, a second branch including the second voltage source VS2 and a second diode D2 and coupling in parallel to the first branch, and a first switch S1 coupling an intermediate node between the first voltage source and the first diode D1 to an intermediate node between the second voltage source and the second diode D2. In an example, the first switch S1 may be an IGBT.

The second conversion unit CU2 includes a first branch including the third voltage source VS3 and a third diode D3, a second branch including the fourth voltage source VS4 and a fourth diode D4 and coupling in parallel to the first branch, and a second switch S2 coupling an intermediate node between the third voltage source VS3 and the third diode D3 to an intermediate node between the fourth voltage source VS4 and the fourth diode D4. In an example, the second switch S2 may be an IGBT.

In an example, at least one of the first, second, third and fourth voltage sources VS1, VS2, VS3 and VS4 includes a capacitor charged from the input voltage. The first conversion unit CU1 may further comprises a first inductor L1 coupled to the first and second branches of the first conversion unit CU1 to boost the voltage. The second conversion unit CU2 further comprises a second inductor L2 coupled to the first and second branches of the second conversion unit CU2 to boost the voltage.

The DC-DC converter 16 also includes a switching circuit SC coupled to the first and second conversion units, and the controller 12 coupled to the switching circuit SC. In an example, the switching circuit SC may include a fifth diode D5, a sixth diode D6 and a third switch S3. The fifth diode D5 is coupled to the first terminals of the first and second conversion units. The sixth diode D6 is coupled to the second terminals of the first and second conversion units. The third switch S3 is coupled between the second terminal of the first conversion unit and the first terminal of the second conversion unit. In an example, the third switch S3 may be an IGBT.

The controller 12 is configured to in response to receiving an indication of voltage, cause the switching circuit SC to couple the first and second conversion units in parallel or in series, cause the first and second voltage sources in series or in parallel, and cause the third and fourth voltage sources in series or in parallel to generate a output voltage.

In an example, when the electronic vehicle 4 is electrically coupled to the electronic device 10, the electronic vehicle 4 may transmit an indication of voltage, e.g., data indicating its required voltage or voltage range, to the electronic device 10, such that the electronic vehicle 4 can determine an appropriate charging scheme, such as an appropriate output voltage for the electronic vehicle 4.

In response to determining the appropriate charging scheme, the controller 12 may couple the first and second conversion units CU1 and CU2 in parallel or in series by turning on or off the third switch S3 in the switching unit SC. In addition, the controller 12 may cause the first and second voltage sources VS1 and VS2 in series or in parallel by turning on or off the first switch S1, and cause the third and fourth voltage sources VS3 and VS4 in series or in parallel to generate an output voltage by turning on or off the second switch S2.

In an example, the switches of the first and second conversion units CU1 and CU2 may operate in a pulse width modulation (PWM) mode, and duty cycles of the switches can be adjusted. For example, the controller 12 is further coupled to the first and second conversion units CU1 and CU2, and configured to adjust duty cycle of the switch S1 of the first conversion unit CU1 based on the indication of voltage; and adjust duty cycle of the switch S2 of the second conversion unit CU2 based on the indication of voltage.

In the process of charging, constant output power may be desired since it may be beneficial for the long time service life of an electronic device, such as an electronic vehicle. However, it is difficult for conventional approaches to achieve a constant output power across a wide voltage range, especially when the configuration is changed from a series configuration to a parallel configuration. This is because the output current has a significantly step drop during changes.

With the configuration of Fig. 4, a constant output power across a wide voltage range may be achieved. In an embodiment, the controller 12 is configured to determine an operation mode based on the received indication of voltage; and based on the determined operation mode, adjust the input voltage and/or control switches of the first and second conversion units and the switching circuit.

For example, the schematic circuit of Fig. 4 may include various operation modes, and the DC-DC converter 16 may provide a substantially constant output power across the various modes. In an example, the DC-DC converter 16 may include five operation modes with different output voltage ranges at the output terminal Vout of Fig. 4.

The first operation mode is directed to an output voltage range from 190V to 250V, the second operation mode is directed to an output voltage range from 250V to 375V, the third operation mode is directed to an output voltage range from 375V to 500V, the fourth operation mode is directed to an output voltage range from 500V to 750V, and the fifth operation mode is directed to an output voltage range from 750V to 1000V.

Although five operation modes for five voltage ranges are illustrated, this is only for illustration without suggesting any limitations as to the scope of the subject matter described here. For example, less or more operation modes for corresponding numbers of voltage ranges may be applied. Hereinafter, it will describe details of providing a substantially constant output power across such a wide voltage range.

In an example, the controller 12 receives the indication of voltage from the electronic vehicle 4, and the controller 12 determines the first operation mode based on the indication. In responding to the determination, the controller 12 adjusts output voltage of the AC source 2 without turning on the first, second and third switches S1, S2 and S3.

In this scenario, the four voltage sources VS1, VS2, VS3 and VS4 are coupled in parallel to charge the output capacitor Cout to provide an output voltage Vout across the output capacitor Cout. The AC source 2 may be adjusted from 600V to 800V to provide the output voltage Vout from 190V to 250V, and the current from the voltage sources VS1, VS2, VS3 and VS4 can be from 315A to 240A in total.

In an example, the controller 12 receives the indication of voltage from the electronic vehicle 4, and the controller 12 determines the second operation mode, based on the indication or based on the output voltage Vout arriving at the boundary between the first and second operation modes.

In responding to the determination, the controller 12 adjusts output voltage of the AC source 2 to be fixed at a voltage, such as 600V, and maintains the turning-off of the third switch S3. In the meantime, the controller 12 controls the first and second switch S1 and S2 to operate in a PWM manner. In other words, the first and second switch S1 and S2 are both alternatively turned on and off to generate the output voltage Vout.

In this scenario, the two conversion units CU1 and CU2 are coupled in parallel, while the voltage sources inside the conversion unit may be alternatively coupled in series and in parallel. By adjusting duty cycles of the first and second switches S1 and S2, the output voltage Vout can be from 250V to 375V, and the current from the voltage sources VS1, VS2, VS3 and VS4 can be from 240A to 160A in total. As such, a “smooth” mode change can be achieved, and a substantially constant output voltage can be achieved, even in the mode change phase.

In an example, the controller 12 receives the indication of voltage from the electronic vehicle 4, and the controller 12 determines the third operation mode, based on the indication or based on the output voltage Vout arriving at the boundary between the second and third operation modes.

In responding to the determination, the controller 12 adjusts output voltage of the AC source 2 from 600V to 800V, turns on the first and second switches S1 and S2, and keeps turning off the third switch S3.

In this scenario, the first and second voltage sources VS1 and VS2 are coupled in series, the third and fourth voltage sources VS3 and VS4 are coupled in series, and the conversion units CU1 and CU2 are coupled in parallel to charge the output capacitor Cout to provide an output voltage Vout across the output capacitor Cout. The AC source 2 may be adjusted from 600V to 800V to provide the output voltage Vout from 375V to 500V, and the current from the voltage sources VS1, VS2, VS3 and VS4 can be from 160A to 120A in total. As such, a “smooth” mode change can be achieved, and a substantially constant output voltage can be achieved, even in the mode change phase.

In an example, the controller 12 receives the indication of voltage from the electronic vehicle 4, and the controller 12 determines the fourth operation mode, based on the indication or based on the output voltage Vout arriving at the boundary between the third and fourth operation modes.

In responding to the determination, the controller 12 fixes output voltage of the AC source 2 to be 600V, and turns on the third switch S3. In the meantime, the controller 12 controls the first and second switch S1 and S2 to operate in the PWM manner. In other words, the first and second switch S1 and S2 are both alternatively turned on and off to generate the output voltage Vout.

In this scenario, the two conversion units CU1 and CU2 are coupled in series, while the voltage sources inside the conversion unit may be alternatively coupled in series and in parallel. By adjusting duty cycles of the first and second switches S1 and S2, the output voltage Vout can be from 500V to 750V, and the current from the voltage sources VS1, VS2, VS3 and VS4 can be from 160A to 80A in total. As such, a “smooth” mode change can be achieved, and a substantially constant output voltage can be achieved, even in the mode change phase.

In an example, the controller 12 receives the indication of voltage from the electronic vehicle 4, and the controller 12 determines the fifth operation mode, based on the indication or based on the output voltage Vout arriving at the boundary between the fourth and fifth operation modes.

In responding to the determination, the controller 12 turns on the first, second and third switches S1, S2 and S3. In the meantime, the controller 12 adjusts output voltage of the AC source 2 from 600V to 800V to provide the output voltage Vout from 750V to 1000V, and the current from the voltage sources VS1, VS2, VS3 and VS4 can be from 80A to 60A in total. As such, the “smooth” mode change can be achieved, and a substantially constant output voltage can be achieved, even in the mode change phase.

The above five operation modes can be summarized in Table 1 below.

Table 1. Summary of the proposed topology operation modes

During all operation in all the five operation modes, the AC-DC converter 14 may operate in a fixed switching frequency, such that the loss, size and cost of the AC-DC converter 14 may be reduced without being affected by variable switching frequency. This can further increase efficiency of the converter.

In addition, with the configuration of Figs. 3 and 4, it is able to output constant power across the full output voltage range without over design on the power semiconductor and magnetic components.

Fig. 5 illustrates an example of a method for manufacturing a converter in accordance with some example embodiments of the present disclosure. The method may be applied to manufacture the converter 16.

At 202, it is provided a first conversion unit including a first voltage source and a second voltage source and configured to generate a first voltage from an input voltage.

At 204, it is provided a second conversion unit including a third voltage source and a fourth voltage source and configured to generate a second voltage from the input voltage.

At 206, it is to couple a switching circuit to the first and second conversion units.

At 208, it is to couple a controller to the first and second conversion units and the switching circuit. The controller is configured to in response to receiving an indication of voltage, cause the switching circuit to couple the first and second conversion units in parallel or in series, cause the first and second voltage sources in series or in parallel, and cause the third and fourth voltage sources in series or in parallel to generate a output voltage.

Although the method 200 is illustrated in Fig. 5, this is only for illustration without suggesting any limitations as to the scope of the subject matter described here. For example, it is to be understood that all the features for the Figs. 1-4 can be applied to the method 200.

Hereinafter, some example implementations of the subject matter described herein will be listed.

Item 1: There is provided a converter. The converter comprises a first conversion unit including a first voltage source and a second voltage source and configured to generate a first voltage from an input voltage; a second conversion unit including a third voltage source and a fourth voltage source and configured to generate a second voltage from the input voltage; a switching circuit coupled to the first and second conversion units; and a controller coupled to the first and second conversion units and the switching circuit, and configured to in response to receiving an indication of voltage, cause the switching circuit to couple the first and second conversion units in parallel or in series, cause the first and second voltage sources in series or in parallel, and cause the third and fourth voltage sources in series or in parallel to generate a output voltage.

Item 2: The converter of Item 1, wherein the first conversion unit comprises a first branch including the first voltage source and a first diode , a second branch including the second voltage source and a second diode and coupling in parallel to the first branch, and a first switch coupling an intermediate node between the first voltage source and the first diode to an intermediate node between the second voltage source and the second diode ; and the second conversion unit comprises a first branch including the third voltage source and a third diode, a second branch including the fourth voltage source and a fourth diode and coupling in parallel to the first branch, and a second switch coupling an intermediate node between the third voltage source and the third diode to an intermediate node between the fourth voltage source and the fourth diode.

Item 3: The converter of

Item

1 or 2, wherein the controller is further coupled to the first and second conversion units, and configured to adjust duty cycle of a switch of the first conversion unit operating in a first PWM mode based on the indication of voltage; and adjust duty cycle of a switch of the second conversion unit operating in a second PWM mode based on the indication of voltage.

Item 4: The converter of any of Items 1-3, wherein the switching circuit comprises a fifth diode coupled to first terminals of the first and second conversion units, a sixth diode coupled to second terminals of the first and second conversion units, and a third switch coupled between the second terminal of the first conversion unit and the first terminal of the second conversion unit.

Item 5: The converter of any of Items 1-4, wherein at least one of the first, second, third and fourth voltage sources includes a capacitor charged from the input voltage, the first conversion unit further comprises a first inductor coupled to the first and second branches of the first conversion unit; and the second conversion unit further comprises a second inductor coupled to the first and second branches of the second conversion unit.

Item 6: The converter of any of Items 1-5, wherein the controller is further configured to determine an operation mode based on the received indication of voltage; and based on the determined operation mode, adjust the input voltage and/or control switches of the first and second conversion units and the switching circuit.

Item 7: The converter of any of Items 1-6, wherein adjusting the input voltage and/or controlling switches of the first and second conversion units and the switching circuit comprises: in response to determining a first operation mode, adjusting the input voltage and turning off the first switch, the second switch and the third switch.

Item 8: The converter of any of Items 1-7, wherein adjusting the input voltage and/or controlling switches of the first and second conversion units and the switching circuit comprises: in response to determining a second operation mode, adjusting duty cycles of the first and second switches based on the indication of voltage, and turning off the third switch without adjusting the input voltage.

Item 9: The converter of any of Items 1-8, wherein adjusting the input voltage and/or controlling switches of the first and second conversion units and the switching circuit comprises: in response to determining a third operation mode, adjusting the input voltage, turning on the first switch and the second switch; and turning off the third switch.

Item 10: The converter of any of Items 1-8, wherein adjusting the input voltage and/or controlling switches of the first and second conversion units and the switching circuit comprises: in response to determining a fourth operation mode, adjusting duty cycle of the first and second switches based on the indication of voltage, and turning on the third switch without adjusting the input voltage.

Item 11: The converter of any of Items 1-10, wherein adjusting the input voltage and/or controlling switches of the first and second conversion units and the switching circuit comprises: in response to determining a fifth operation mode, adjusting the input voltage, turning on the first and second switches; and turning on the third switch.

Item 12: The converter of any of Items 1-11, wherein the first voltage source is coupled in parallel to the second voltage source in case that the first switch is turned off; the first voltage source is coupled in series with the second voltage source in case that the first switch is turned on; the third voltage source is coupled in parallel to the fourth voltage source in case that the second switch is turned off; and the third voltage source is coupled in series with the fourth voltage source in case that the second switch is turned on.

Item 13: The converter of any of Items 1-12, wherein the controller is further configured to cause the converter to output a substantially constant power during the operation modes by adjusting the input voltage and/or controlling switches of the first and second conversion units.

Item 14: It is provided an electronic device. The electronic device comprises an AC-DC converter, and a converter of any of Items 1-13 coupled to the AC-DC converter and configured to convert a first DC voltage from the AC-DC converter into a second DC voltage.

Item 15: It is provided a method for manufacturing a converter. The method comprises providing a first conversion unit including a first voltage source and a second voltage source and configured to generate a first voltage from an input voltage; providing a second conversion unit including a third voltage source and a fourth voltage source and configured to generate a second voltage from the input voltage, coupling a switching circuit to the first and second conversion units; and coupling a controller to the first and second conversion units and the switching circuit, the controller configured to in response to receiving an indication of voltage, cause the switching circuit to couple the first and second conversion units in parallel or in series, cause the first and second voltage sources in series or in parallel, and cause the third and fourth voltage sources in series or in parallel to generate a output voltage.

Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. On the other hand, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable sub-combination.

Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

A converter (16) , comprising:

a first conversion unit (CU1) including a first voltage source (VS1) and a second voltage source (VS2) and configured to generate a first voltage from an input voltage;

a second conversion unit (CU2) including a third voltage source (VS3) and a fourth voltage source (VS4) and configured to generate a second voltage from the input voltage,

a switching circuit (SC) coupled to the first and second conversion units; and

a controller (12) coupled to the first and second conversion units and the switching circuit (SC) , and configured to in response to receiving an indication of voltage, cause the switching circuit (SC) to couple the first and second conversion units in parallel or in series, cause the first and second voltage sources in series or in parallel, and cause the third and fourth voltage sources in series or in parallel to generate a output voltage.
The converter of claim 1, wherein the first conversion unit (CU1) comprises a first branch including the first voltage source and a first diode (D1) , a second branch including the second voltage source and a second diode (D2) and coupling in parallel to the first branch, and a first switch (S1) coupling an intermediate node between the first voltage source and the first diode (D1) to an intermediate node between the second voltage source and the second diode (D2) ; and

the second conversion unit (CU2) comprises a first branch including the third voltage source and a third diode (D3) , a second branch including the fourth voltage source and a fourth diode (D4) and coupling in parallel to the first branch, and a second switch (S2) coupling an intermediate node between the third voltage source (VS3) and the third diode (D3) to an intermediate node between the fourth voltage source (VS4) and the fourth diode (D4) .
The converter of claim 2, wherein the controller is further coupled to the first and second conversion units, and configured to

adjust duty cycle of a switch of the first conversion unit operating in a first pulse width modulation (PWM) mode based on the indication of voltage; and

adjust duty cycle of a switch of the second conversion unit operating in a second PWM mode based on the indication of voltage.
The converter of claim 2, wherein the switching circuit (SC) comprises a fifth diode (D5) coupled to first terminals of the first and second conversion units, a sixth diode (D6) coupled to second terminals of the first and second conversion units, and a third switch (S3) coupled between the second terminal of the first conversion unit and the first terminal of the second conversion unit.
The converter of claim 2, wherein at least one of the first, second, third and fourth voltage sources includes a capacitor charged from the input voltage,

the first conversion unit (CU1) further comprises a first inductor (L1) coupled to the first and second branches of the first conversion unit (CU1) ; and

the second conversion unit (CU2) further comprises a second inductor (L2) coupled to the first and second branches of the second conversion unit (CU2) .
The converter of claim 4, wherein the controller is further configured to

determine an operation mode based on the received indication of voltage; and

based on the determined operation mode, adjust the input voltage and/or control switches of the first and second conversion units and the switching circuit.
The converter of claim 6, wherein adjusting the input voltage and/or controlling switches of the first and second conversion units and the switching circuit comprises:

in response to determining a first operation mode, adjusting the input voltage and turning off the first switch (S1) , the second switch (S2) and the third switch (S3) .
The converter of claim 7, wherein adjusting the input voltage and/or controlling switches of the first and second conversion units and the switching circuit comprises:

in response to determining a second operation mode,

adjusting duty cycles of the first and second switches based on the indication of voltage, and

turning off the third switch without adjusting the input voltage.
The converter of claim 8, wherein adjusting the input voltage and/or controlling switches of the first and second conversion units and the switching circuit comprises:

in response to determining a third operation mode,

adjusting the input voltage,

turning on the first switch and the second switch; and

turning off the third switch.
The converter of claim 9, wherein adjusting the input voltage and/or controlling switches of the first and second conversion units and the switching circuit comprises:

in response to determining a fourth operation mode,

adjusting duty cycle of the first and second switches based on the indication of voltage, and

turning on the third switch without adjusting the input voltage.
The converter of claim 10, wherein adjusting the input voltage and/or controlling switches of the first and second conversion units and the switching circuit comprises:

in response to determining a fifth operation mode,

adjusting the input voltage,

turning on the first and second switches; and

turning on the third switch.
The converter of claim 2, wherein the first voltage source is coupled in parallel to the second voltage source in case that the first switch is turned off;

the first voltage source is coupled in series with the second voltage source in case that the first switch is turned on;

the third voltage source is coupled in parallel to the fourth voltage source in case that the second switch is turned off; and

the third voltage source is coupled in series with the fourth voltage source in case that the second switch is turned on.
The converter of claim 6, wherein the controller is further configured to cause the converter to output a substantially constant power during the operation modes by adjusting the input voltage and/or controlling switches of the first and second conversion units.
An electronic device, comprises:

an AC-DC converter, and

a converter (16) of claim 1 coupled to the AC-DC converter and configured to convert a first DC voltage from the AC-DC converter into a second DC voltage.
A method for manufacturing a converter, comprising:

providing a first conversion unit (CU1) including a first voltage source (VS1) and a second voltage source (VS2) and configured to generate a first voltage from an input voltage;

providing a second conversion unit (CU2) including a third voltage source (VS3) and a fourth voltage source (VS4) and configured to generate a second voltage from the input voltage,

coupling a switching circuit (SC) to the first and second conversion units; and

coupling a controller (12) to the first and second conversion units and the switching circuit (SC) , the controller configured to in response to receiving an indication of voltage, cause the switching circuit (SC) to couple the first and second conversion units in parallel or in series, cause the first and second voltage sources in series or in parallel, and cause the third and fourth voltage sources in series or in parallel to generate a output voltage.