Charging power supply power synthesis system and method

Abstract

The invention provides a charging power supply power synthesis system and method, and relates to the technical field of electric vehicle charging, the system comprises an input inductance unit, an input rectification unit, a bus capacitor, a voltage regulation unit, an output inductance unit and an output filter capacitor which are connected in sequence; wherein the voltage regulating unit comprises an inversion unit, a transformer and an output rectification unit which are connected in sequence; the inversion units at the input side of the voltage regulation unit are connected in parallel, and the output rectification units at the output side of the voltage regulation unit are connected in series. The output power and the output voltage of the charging power supply provided by the invention can be adjusted as required, the continuously increasing battery capacity and charging power requirements of electrical equipment can be met, and the power supply is small in size, high in power density, good in universality, easy to upgrade and update, and simple and convenient to maintain.

Description

Technical Field

[0001] The present invention relates to the technical field of electric vehicle charging, and particularly to a charging power synthesis system and method with a wide output voltage range. Background Art

[0002] With the progress of technology and the development of science and technology, environmental pollution has become increasingly serious. As a new type of transportation, new energy electric vehicles have incomparable advantages in alleviating the energy crisis and improving urban air quality, and are the main direction of future vehicle development. The charging device provides energy for the operation of electric vehicles and is an important basic support for electric vehicles; while the charging power module, as the core component of the DC fast charging device, is a research hotspot in the field of new energy electric vehicle development.

[0003] At present, due to the limitations of the capacity of semiconductor power devices and the constraints of magnetic materials of high-frequency transformers in the charging power module of electric vehicles, the output power of a single power module is small and the output voltage is low, which in turn leads to a small output power of the charging pile, a narrow output voltage range, slow charging speed, low efficiency, and cannot meet the requirements of high-power and wide-voltage-range charging. Moreover, the charging power supply has a large volume and a low power density.

[0004] Therefore, there is an urgent need for a charging power synthesis method that can provide a larger output power and a wider output voltage range to improve the charging speed and meet the charging requirements of electric vehicles. Summary of the Invention

[0005] The present invention provides a charging power synthesis system and method for solving the technical problems of small output power and narrow output voltage range of current charging piles.

[0006] On the one hand, the present invention provides a charging power synthesis system, which includes an input inductor unit, an input rectifier unit, a bus capacitor, a voltage regulating unit, an output inductor unit, and an output filter capacitor connected in sequence; Among them, the voltage regulating unit includes an inverter unit, a transformer, and an output rectifier unit connected in sequence; the inverter unit on the input side of the voltage regulating unit adopts a parallel connection method, and the output rectifier unit on the output side of the voltage regulating unit adopts a series connection method.

[0007] Further, the connection of the voltage regulating unit specifically includes: The inverter unit includes M inverter modules; the input ends of the M inverter modules are connected in parallel to the bus capacitor, and the output ends of the M inverter modules are correspondingly connected to the M primary input ports of the transformer; The output rectification unit includes M output rectification modules; the input ends of the M output rectification modules are correspondingly connected to the M secondary output ports of the transformer, and the output ends of the M output rectification modules are connected in series to the output inductance unit.

[0008] Further, the M primary input ports and the M secondary output ports of the transformer share a set of magnetic cores.

[0009] Further, the input inductance unit includes a plurality of N-phase coupled inductors; each N-phase coupled inductor includes an input end and N output ends, the input end of the N-phase coupled inductor is connected to a power supply, and the N output ends of the N-phase coupled inductor are correspondingly connected to N input rectification modules.

[0010] Further, the input rectification unit includes N input rectification modules; the output ends of the N input rectification modules are connected in parallel to the bus capacitor.

[0011] Further, the output inductance unit is a plurality of differential-mode inductors, which are respectively connected to the positive and negative poles of the output rectification unit.

[0012] Further, there are three N-phase coupled inductors, and the input ends of the three N-phase coupled inductors are respectively connected to three-phase electricity.

[0013] Further, the output power and the output voltage range are adjusted by adjusting the number of inverter modules and rectification modules.

[0014] Further, the inverter module is an inverter circuit with any topology, and the rectification module is a rectification circuit with any topology.

[0015] On the other hand, the present invention also provides a method for synthesizing the power of a charging power supply using a charging power supply power synthesis system as described in any one of the above, the method includes: adjusting the output power and the output voltage range by adjusting the number of inverter modules and output rectification modules.

[0016] Generally speaking, the present invention provides a charging power supply power synthesis system and method. Through the technical solution conceived by the present invention, compared with the prior art, the following beneficial effects can be obtained: (1) The present invention will connect the inverter unit, transformer, and output rectifier unit in a front-parallel and rear-series connection manner; since the connection method on the input side of the voltage regulation unit is parallel connection and the connection method on the output side of the voltage regulation unit is series connection, the voltages of each inverter module on the input side will be forced to be equal, and the currents of each output rectifier module on the output side will be forced to be equal, making the voltage regulation unit as a whole exhibit the characteristics of input self-equalizing voltage and output self-equalizing current. This power synthesis method can not only improve the output power level of the charging power supply while ensuring high power density and wide output voltage range of the power supply; but also ensure the stable operation of the system by performing equalizing voltage control on the output rectifier module; thus meeting the requirements of the output power and output voltage of the charging power supply in the actual application of electrical equipment.

[0017] (2) The present invention adopts modular interleaved control, so that the output power borne by the input rectifier module is 1 / N of the total output power, and the output power borne by the inverter module and the output rectifier module is 1 / M of the total output power. Through this modular design, not only can the output power and output voltage of the charging power supply be adjusted according to the number of modules to meet the continuously increasing battery capacity and charging power requirements of electrical equipment; but also the losses and voltage and current ripples on the output side are greatly reduced, facilitating the individual design of sub-modules and the overall design of the system, with good versatility, easy upgrading and replacement, and simple maintenance, improving the overall reliability of the charging power supply.

[0018] (3) The transformer of the present invention is a transformer with a common magnetic core, and all transformers share a set of magnetic cores, which not only reduces the volume of the transformer but also further improves the power density of the charging power supply.

[0019] (4) The present invention reduces the volume of the input inductor through the form of the coupling inductor and its connection method, and improves the power density of the charging power supply to a certain extent.

[0020] (5) The output inductor of the present invention is a plurality of differential-mode inductors, which are respectively connected to the positive and negative poles of the output rectifier unit and connected to the output filter capacitor. This connection method can reduce the output ripple and improve the stability of the output voltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0022] Figure 1 It is a schematic diagram of the system architecture of a charging power supply power synthesis system and method provided by the present invention; Figure 2 It is a circuit schematic diagram of a specific embodiment of a charging power supply power synthesis system and method provided by the present invention. Specific Embodiments

[0023] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below in conjunction with the accompanying drawings and embodiments in the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without making creative efforts belong to the scope of protection of the present invention.

[0024] It should be noted that in the description of the embodiments of the present invention, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a system, method or device including a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such system, method or device. Without further limitations, an element defined by the statement "including one..." does not exclude the existence of additional identical elements in the system, method or device including the said element.

[0025] The present invention provides a charging power supply power synthesis system with a wide output voltage range to improve the output power level of the charging power supply while ensuring high power density and wide output voltage range of the power supply to meet the high-power charging requirements with relatively high ratio requirements for the output-side voltage and input-side voltage of the charging power supply in the actual application of electrical equipment.

[0026] As Figure 1 shown, this system includes an input inductance unit, an input rectification unit, a bus capacitor, a voltage regulation unit, an output inductance unit, and an output filter capacitor connected in sequence. Among them, the voltage regulation unit includes an inverter unit, a transformer, and an output rectification unit connected in sequence.

[0027] Specifically, the input end of the input inductance unit is connected to the input power supply, the output end of the input inductance unit is connected to the input end of the input rectification unit, the DC output end of the input rectification unit is connected to the bus capacitor and then to the input end of the inverter unit, the output end of the inverter unit is connected to the primary input port of the transformer, the secondary output port of the transformer is connected to the input end of the output rectification unit, the output end of the output rectification unit is connected to the output inductance and then to the output filter capacitor, and finally, a high-power and wide-voltage-range direct current is output through the output filter capacitor.

[0028] It should be noted that the inverter unit on the input side of the voltage regulating unit adopts a parallel connection method, and the output rectifier unit on the output side of the voltage regulating unit adopts a series connection method. That is to say, the inverter unit of the voltage regulating unit is connected in parallel with the transformer, and the output rectifier unit is connected in series with the transformer.

[0029] The inverter unit, the transformer, and the output rectifier unit as a whole are in the form of parallel connection at the front and series connection at the back. Since the connection method on the input side of the voltage regulating unit is parallel connection, the voltages of the respective inverter modules on the input side will be forced to be equal. Since the connection method on the output side of the voltage regulating unit is series connection, the currents of the respective output rectifier modules on the output side will be forced to be equal; this makes the voltage regulating unit as a whole exhibit the characteristics of input self-equalizing voltage and output self-equalizing current.

[0030] This power synthesis method can not only improve the output power level of the charging power supply while ensuring the high power density and wide output voltage range of the power supply; but also can ensure the stable operation of the system by performing equalizing voltage control on the output rectifier modules; thus meeting the requirements for the output power and output voltage of the charging power supply in the actual application of electrical equipment.

[0031] As an embodiment, the connection of the voltage regulating unit specifically includes: the inverter unit includes M inverter modules; the input ends of the M inverter modules are connected in parallel to the bus capacitor, and the output ends of the M inverter modules are correspondingly connected to the M primary input ports of the transformer; the output rectifier unit includes M output rectifier modules; the input ends of the M output rectifier modules are correspondingly connected to the M secondary output ports of the transformer, and the output ends of the M output rectifier modules are connected in series to the output inductor unit; M is a positive integer.

[0032] This connection method reduces the requirements for the performance of the transformer, allows a transformer with a smaller number of turns to be selected, improves the output power of the charging power supply, and the range of the output voltage can be increased by M times.

[0033] As an embodiment, the M primary input ports and the M secondary output ports of the transformer share a set of magnetic cores. That is to say, the transformer can be a common magnetic core transformer, the M transformers share a set of magnetic cores, the M primary ports of the common magnetic core transformer are respectively connected to the output ends of the M inverter modules, and the M secondary ports of the common magnetic core transformer are respectively connected to the M output rectifier modules. The M transformers sharing a set of magnetic cores not only reduces the volume of the transformer, but also further improves the power density of the charging power supply.

[0034] It should be noted that by adopting this modular interleaved control, the output power borne by the input rectification module is 1 / N of the total output power, and the output powers borne by the inverter module and the output rectification module are 1 / M of the total output power. This not only enables the output power and output voltage of the charging power supply to be adjusted in levels according to the number of modules to meet the continuously increasing battery capacity and charging power requirements of electrical equipment, but also greatly reduces the losses and voltage and current ripples on the output side, facilitating the individual design of sub-modules and the overall design of the system, with good versatility, easy upgrade and replacement, simple maintenance, and improved overall reliability of the charging power supply.

[0035] When charging using this charging power supply power synthesis system, the output power and output voltage range can be adjusted by adjusting the number of inverter modules and rectifier modules.

[0036] Specifically, when there are inverter modules and rectifier modules, the maximum output voltage of the system is , and the maximum output power is ; Among them, , respectively represent the maximum output voltage and maximum output power of the system when there is only one inverter module and one rectifier module.

[0037] In other words, when there is only one inverter module and one rectifier module, the maximum output voltage is , and the maximum output power is ; when M inverter modules and M output rectifier modules are connected, the output ends of the M inverter modules are correspondingly connected to M primary input ports of the transformer, the input ends of the M output rectifier modules are correspondingly connected to M secondary output ports of the transformer, and the M transformers share a set of magnetic cores, then the maximum output voltage is , and the maximum output power is .

[0038] As an embodiment, the input inductance unit includes a plurality of N-phase coupled inductors; each N-phase coupled inductor includes an input end and N output ends, the input end of the N-phase coupled inductor is connected to the power supply, and the N output ends of the N-phase coupled inductor are correspondingly connected to N input rectification modules. In the form of coupled inductors, not only the volume of the input inductor is reduced, but also the power density of the charging power supply is improved to a certain extent.

[0039] Furthermore, there are three N-phase coupled inductors, and the input ends of the three N-phase coupled inductors are respectively connected to three-phase electricity. The three-phase input ends of the three N-phase coupled inductors are respectively connected to three-phase input electricity, and the three-phase output ends of the input inductance unit are connected to the input end of the input rectification unit.

[0040] As an embodiment, the input rectification unit includes N input rectification modules; the output ends of the N input rectification modules are connected in parallel to the bus capacitor. More specifically, three N-phase coupled inductors are respectively connected to the three-phase input ends of the N rectification modules. This modular interleaved control makes the output power borne by each input rectification module 1 / N of the total output power; N is a positive integer.

[0041] As an embodiment, the output inductor unit is multiple differential-mode inductors, which are respectively connected to the positive and negative poles of the output rectification unit. For example, the output inductors are two differential-mode inductors, which are respectively connected to the positive and negative poles of the output rectification unit and are connected to the output filter capacitor; thereby reducing the output ripple and improving the stability of the output voltage.

[0042] It should be noted that the circuit of the inverter unit can be an inverter circuit with any topology. For example, the inverter unit can be a single-phase PWM bridge inverter circuit, a half-bridge three-level inverter circuit, an H6 topology circuit, etc. The circuit of the rectification module can also be a rectification circuit with any topology. For example, the input rectification module can be a three-phase PWM bridge rectification circuit, a Vienna rectification circuit, a three-phase uncontrolled rectification circuit, etc.; the output rectification can be a single-phase PWM half-bridge rectification circuit, a single-phase PWM full-bridge rectification circuit, a single-phase uncontrolled rectification circuit, etc.

[0043] As a specific embodiment, its circuit schematic diagram is as Figure 2 shown, including an input inductor unit, an input rectification unit, a bus capacitor, a voltage regulation unit, an output inductor unit, and an output filter capacitor connected in sequence.

[0044] Specifically, the input inductor unit is three two-phase coupled inductors; the input rectification unit is two Vienna rectifiers; the inverter unit is two half-bridge three-level inverters; the transformer is a common magnetic core transformer; the output rectification unit is two uncontrolled rectification modules; the output inductor unit is two differential-mode inductors.

[0045] A two-phase coupled inductor has a total of one input end and two output ends. Three two-phase coupled inductors have a total of three input ends and six output ends. Then, the three input ends are respectively connected to three-phase electricity. One output end of a two-phase coupled inductor is connected to the three-phase input end of the first Vienna rectifier, and the other output end is connected to the three-phase input end of the second Vienna rectifier; in this way, each two-phase coupled inductor is simultaneously connected to all Vienna rectifiers.

[0046] The output ends of the two Vienna rectifiers are connected in parallel and then connected to the bus capacitor.

[0047] The input ends of two half-bridge three-level inverters are connected in parallel to the bus capacitor, and the output ends are respectively connected to the two primary ports of a common magnetic core transformer; the input ends of two uncontrolled rectifier modules are respectively connected to the two secondary ports of the common magnetic core transformer, and after the output ends are connected in series, they are then connected to two differential mode inductors, which not only reduces the volume of the transformer, but also further improves the power density of the charging power supply.

[0048] The output ends after the two uncontrolled rectifier modules are connected in series include positive and negative poles. One differential mode inductor is connected to the positive pole of the output end, and the other differential mode inductor is connected to the negative pole of the output end; the two differential mode inductors are simultaneously connected to the output filter capacitor.

[0049] In this embodiment, the two half-bridge three-level inverters, the common magnetic core transformer, and the two uncontrolled rectifier modules are overall in the form of front parallel and rear series. This connection method reduces the requirements for the performance of the transformer, and a transformer with a smaller turns ratio can be selected, thereby increasing the power output by the charging power supply, and the output voltage range can be increased by 2 times. In addition, since the connection method of the input ends of the half-bridge three-level inverters is parallel connection, the input voltages of the half-bridge three-level inverters on the input side will be forced to be equal; the connection method of the output ends of the uncontrolled rectifier modules is series connection, so the output currents of the uncontrolled rectifier modules will be forced to be equal; thus, the voltage regulating unit as a whole exhibits the characteristics of input self-equalizing voltage and output self-equalizing current.

[0050] In this embodiment, the output powers borne by the Vienna rectifier, the half-bridge three-level inverter, and the uncontrolled rectifier module are all 1 / 2 of the total output power. By adjusting the number of inverter modules and output rectifier modules, the voltage power level on the output side can be increased, the loss can be reduced, and the voltage ripple on the output side can be reduced.

[0051] On the other hand, the present invention also provides a method for synthesizing the power of a charging power supply. By adjusting the number of inverter modules and output rectifier modules in the above-mentioned charging power supply power synthesis system, the adjustment of the output power and the output voltage range can be achieved. The specific technical features are not elaborated here.

[0052] In summary, the output power and output voltage of the charging power supply proposed by the present invention can be adjusted according to needs, which can not only meet the continuously growing battery capacity and charging power requirements of electrical equipment, but also has a small power supply volume, high power density, good versatility, is easy to upgrade and replace, and is easy to maintain.

[0053] It should be noted that, for the foregoing embodiments, for the sake of simple description, they are all described as a series of action combinations. However, those skilled in the art should know that this application is not limited by the described action sequence, because according to this application, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily essential to this application.

[0054] In the above embodiments, the descriptions of the respective embodiments have their own emphases. For the parts not detailed in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0055] In the several embodiments provided by this application, it should be understood that the disclosed method or system can be implemented in other ways. For example, the above-described embodiments are merely illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed.

[0056] The units described as separate components may or may not be physically separated. The components shown as units may or may not be physical units, that is, they can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0057] In addition, in each embodiment of this application, the functional units can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above-mentioned integrated units can be implemented in the form of hardware or in the form of software functional units.

[0058] If the above-mentioned integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable memory. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a memory and includes several instructions for causing a computer device (which can be a personal computer, a server or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of this application.

[0059] Those of ordinary skill in the art can understand that all or part of each circuit in the above embodiments can be completed by instructing relevant hardware through a program, and the program can be stored in a computer-readable memory, which may include: a flash drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, an optical disc, etc.

[0060] The above are only exemplary embodiments of the present disclosure, and the scope of the present disclosure cannot be limited thereby. That is, any equivalent changes and modifications made in accordance with the teachings of the present disclosure still fall within the scope covered by the present disclosure. After considering the specification and practicing the present disclosure herein, those skilled in the art will readily conceive of other embodiments of the present disclosure. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common general knowledge or conventional technical means in the technical field not described in the present disclosure. The specification and embodiments are only regarded as exemplary, and the scope and spirit of the present disclosure are defined by the claims.

[0061] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0062] Those skilled in the art can easily understand that the above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A charging power supply power synthesis system, characterized in that The system includes an input inductance unit, an input rectification unit, a bus capacitor, a voltage regulation unit, an output inductance unit, and an output filter capacitor, which are connected in sequence. Among them, the voltage regulation unit includes an inverter unit, a transformer, and an output rectification unit, which are connected in sequence; the inverter unit on the input side of the voltage regulation unit adopts a parallel connection method, and the output rectification unit on the output side of the voltage regulation unit adopts a series connection method.

2. The power synthesis system of a charging power supply according to claim 1, characterized in that The connection of the voltage regulation unit specifically includes: The inverter unit includes M inverter modules; the input ends of the M inverter modules are connected in parallel to the bus capacitor, and the output ends of the M inverter modules are correspondingly connected to the M primary input ports of the transformer. The output rectification unit includes M output rectification modules; the input ends of the M output rectification modules are correspondingly connected to the M secondary output ports of the transformer, and the output ends of the M output rectification modules are connected in series to the output inductance unit.

3. The power synthesis system of a charging power supply according to claim 2, wherein, The M primary input ports and the M secondary output ports of the transformer share a set of magnetic cores.

4. The power synthesis system of a charging power supply according to claim 1, wherein The input inductance unit includes multiple N-phase coupled inductors; each N-phase coupled inductor includes an input end and N output ends, the input end of the N-phase coupled inductor is connected to the power supply, and the N output ends of the N-phase coupled inductor are correspondingly connected to N input rectification modules.

5. A charging power supply power synthesis system according to claim 4, characterized in that, The input rectification unit includes N input rectification modules; the output ends of the N input rectification modules are connected in parallel to the bus capacitor.

6. The power combining system of a charging power supply according to claim 2, wherein The output inductance unit is multiple differential-mode inductors, which are respectively connected to the positive and negative poles of the output rectification unit.

7. A charging power supply power synthesis system according to claim 4, characterized in that, There are three N-phase coupled inductors, and the input ends of the three N-phase coupled inductors are respectively connected to three-phase electricity.

8. A charging power supply power synthesis system according to claim 2, characterized in that, The output power and the output voltage range are adjusted by adjusting the number of inverter modules and rectification modules.

9. A charging power supply power synthesis system according to claim 2, characterized in that, The inverter module is an inverter circuit with any topology, and the rectification module is a rectification circuit with any topology.

10. A charging power supply power synthesis method using a charging power supply power synthesis system as described in any one of claims 1 to 9, characterized in that, The method includes: adjusting the output power and the output voltage range by adjusting the number of inverter modules and output rectification modules.

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