Charging power supply power synthesis system and method

Abstract

The present invention provides a charging power supply power synthesis system and method, relating to the field of electric vehicle charging technology. The system includes an input inductor unit, an input rectifier unit, a bus capacitor, a voltage regulator unit, an output inductor unit, and an output filter capacitor connected in sequence. The voltage regulator 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 regulator unit is connected in parallel, and the output rectifier unit on the output side of the voltage regulator unit is connected in series. The output power and output voltage of the charging power supply proposed by the present invention can be adjusted as needed, not only meeting the continuously growing battery capacity and charging power requirements of electrical equipment, but also featuring a small size, high power density, good versatility, easy upgrading, and simple and convenient maintenance.

Description

Technical Field

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

[0002] With technological advancements and scientific developments, environmental pollution is becoming increasingly serious. As a new mode of transportation, new energy electric vehicles offer unparalleled advantages in alleviating energy crises and improving urban air quality, making them a key direction for future automotive development. Charging devices provide energy for electric vehicles and are a crucial foundation for their operation. Charging power modules, as the core component of DC fast charging devices, are a research hotspot in the development of new energy electric vehicles.

[0003] At present, the charging power module of electric vehicles is limited by the capacity of semiconductor power devices and the constraints of high-frequency transformer magnetic materials, resulting in small output power and low output voltage of a single power module. This in turn leads to small output power of charging piles, narrow output voltage range, slow charging rate, low efficiency, and cannot meet the requirements of high-power and wide voltage range charging. In addition, the charging power supply is large in size and has low power density.

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

[0005] The present invention provides a charging power supply power synthesis system and method, which is used to solve the technical problems of low output power and narrow output voltage range of current charging piles.

[0006] In one aspect, the present invention provides a charging power supply power synthesis system, the system comprising 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;

[0007] 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 is connected in parallel, and the output rectifier unit on the output side of the voltage regulating unit is connected in series.

[0008] Furthermore, the connection of the voltage regulating unit specifically includes:

[0009] 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;

[0010] 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.

[0011] Furthermore, the M primary input ports and the M secondary output ports of the transformer share a set of magnetic cores.

[0012] Furthermore, the input inductor 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 rectifier modules.

[0013] Furthermore, the input rectifier unit includes N input rectifier modules; the output ends of the N input rectifier modules are connected in parallel to the bus capacitor.

[0014] Furthermore, the output inductor unit is a plurality of differential mode inductors, which are respectively connected to the positive and negative electrodes of the output rectifier unit.

[0015] Furthermore, there are three N-phase coupled inductors, and input ends of the three N-phase coupled inductors are electrically connected to the three phases respectively.

[0016] Furthermore, the output power and output voltage range can be adjusted by adjusting the number of inverter modules and rectifier modules.

[0017] Furthermore, the inverter module is an inverter circuit of any topology, and the rectifier module is a rectifier circuit of any topology.

[0018] On the other hand, the present invention also provides a charging power synthesis method using a charging power synthesis system as described in any one of the above, the method comprising: adjusting the output power and output voltage range by adjusting the number of inverter modules and output rectifier modules.

[0019] In general, the present invention provides a charging power supply power synthesis system and method. The technical solution conceived by the present invention can achieve the following beneficial effects compared with the existing technology:

[0020] (1) The present invention adopts a front-parallel and back-series connection method to connect the inverter unit, transformer, and output rectifier unit. Since the connection method of the input side of the voltage regulator unit is parallel connection and the connection method of the output side of the voltage regulator unit is series connection, the voltage of each inverter module on the input side will be forced to be equal, and the current of each output rectifier module on the output side will be forced to be equal, so that the voltage regulator unit as a whole presents 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 the high power density and wide output voltage range of the power supply; it can also ensure the stable operation of the system by performing voltage equalization control on the output rectifier module; thereby meeting the output power and output voltage requirements of the charging power supply in actual applications of electrical equipment.

[0021] (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 growing battery capacity and charging power requirements of electrical equipment; but it also greatly reduces the loss and voltage and current ripple on the output side, facilitates the individual design of sub-modules and the overall design of the system, has good versatility, is easy to upgrade, is simple and convenient to maintain, and improves the overall reliability of the charging power supply.

[0022] (3) The transformer of the present invention is a common core transformer. All transformers share a set of cores, which not only reduces the size of the transformer but also further improves the power density of the charging power supply.

[0023] (4) The present invention reduces the volume of the input inductor through the form of coupled inductor and its connection method, thereby improving the power density of the charging power supply to a certain extent.

[0024] (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 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

[0025] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 This is a schematic diagram of the system architecture of a charging power supply power synthesis system and method provided by the present invention;

[0027] Figure 2 It is a circuit diagram of a specific embodiment of a charging power supply power synthesis system and method provided by the present invention. DETAILED DESCRIPTION

[0028] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0029] It should be noted that, in the description of the embodiments of the present invention, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a system, method, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such system, method, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the system, method, or apparatus comprising the element.

[0030] The present invention provides a charging power supply power synthesis system with a wide output voltage range, which is used to 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, so as to meet the high power charging requirements of electrical equipment in practical applications, which require a high ratio of the output side voltage to the input side voltage of the charging power supply.

[0031] like Figure 1 As shown, the system includes an input inductor unit, an input rectifier unit, a bus capacitor, a voltage regulator unit, an output inductor unit, and an output filter capacitor connected in sequence. The voltage regulator unit includes an inverter unit, a transformer, and an output rectifier unit connected in sequence.

[0032] Specifically, the input end of the input inductor unit is connected to the input power supply, the output end of the input inductor unit is connected to the input end of the input rectifier unit, the DC output end of the input rectifier 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 rectifier unit, the output end of the output rectifier unit is connected to the output inductor and then to the output filter capacitor, and finally outputs high-power, wide-voltage range DC power through the output filter capacitor.

[0033] It should be noted that the inverter unit on the input side of the voltage regulator unit is connected in parallel, and the output rectifier unit on the output side of the voltage regulator unit is connected in series. That is, the inverter unit of the voltage regulator unit is connected in parallel with the transformer, and the output rectifier unit is connected in series with the transformer.

[0034] The inverter unit, transformer, and output rectifier unit are generally in the form of parallel connection in front and series connection in back. Since the connection mode of the input side of the voltage regulating unit is parallel connection, the voltage of each inverter module on the input side will be forced to be equal. Since the connection mode of the output side of the voltage regulating unit is series connection, the current of each output rectifier module on the output side will be forced to be equal; so that the voltage regulating unit as a whole presents the characteristics of self-equalizing input voltage and self-equalizing output current.

[0035] This power synthesis method not only improves the output power level of the charging power supply while ensuring high power density and a wide output voltage range; it also ensures stable system operation by controlling the voltage balance of the output rectifier module, thereby meeting the output power and output voltage requirements of the charging power supply in actual applications of electrical equipment.

[0036] 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.

[0037] This connection method reduces the requirements on transformer performance, and a transformer with a smaller number of turns can be selected to increase the output power of the charging power supply, and the output voltage range can be increased by M times.

[0038] In one embodiment, the transformer's M primary input ports and M secondary output ports share a common magnetic core. That is, the transformer can be a common-core transformer. The M transformers share a common magnetic core. The M primary ports of the common-core transformer are connected to the output terminals of the M inverter modules, respectively. The M secondary ports of the common-core transformer are connected to the M output rectifier modules, respectively. The shared core of the M transformers not only reduces the size of the transformer but also further improves the power density of the charging power supply.

[0039] It should be noted that the use of this modular interleaved control makes the output power borne by the input rectifier module 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. This not only allows the output power and output voltage of the charging power supply to be adjusted according to the number of modules to meet the continuously growing battery capacity and charging power requirements of electrical equipment; it also greatly reduces the loss and voltage and current ripple on the output side, facilitates the individual design of sub-modules and the overall design of the system, has good versatility, is easy to upgrade, is simple and convenient to maintain, and improves the overall reliability of the charging power supply.

[0040] When charging is performed using the charging power synthesis system, the output power and output voltage range can be adjusted by adjusting the number of inverter modules and rectifier modules.

[0041] Specifically, when there is Inverter modules and When there are rectifier modules, the maximum output voltage of the system is , the maximum output power is ;

[0042] in, 、 They respectively represent the maximum output voltage and maximum output power of the system when there is only one inverter module and one rectifier module.

[0043] In other words, when there is only one inverter module and one rectifier module, the maximum output voltage is , the maximum output power is When M inverter modules and M output rectifier modules are connected, the output terminals of the M inverter modules are connected to the M primary input ports of the transformer, the input terminals of the M output rectifier modules are connected to the M secondary output ports of the transformer, and the M transformers share a set of magnetic cores, then the maximum output voltage is , the maximum output power is .

[0044] In one embodiment, the input inductor unit includes multiple N-phase coupled inductors; each N-phase coupled inductor includes an input terminal and N output terminals. The input terminal of the N-phase coupled inductor is connected to the power supply, and the N output terminals of the N-phase coupled inductor are connected to N input rectifier modules. The coupled inductor format not only reduces the size of the input inductor but also improves the power density of the charging power supply to a certain extent.

[0045] Furthermore, there are three N-phase coupled inductors, and the input terminals of the three N-phase coupled inductors are respectively connected to the three-phase electrical input. The three-phase input terminals of the three N-phase coupled inductors are respectively connected to the three-phase input, and the three-phase output terminals of the input inductor unit are connected to the input terminal of the input rectifier unit.

[0046] In one embodiment, the input rectifier unit includes N input rectifier modules; the output terminals of the N input rectifier modules are connected in parallel to the bus capacitor. More specifically, three N-phase coupled inductors are connected to the three-phase input terminals of the N rectifier modules. This modular interleaved control ensures that the output power borne by the input rectifier module is 1 / N of the total output power, where N is a positive integer.

[0047] In one embodiment, the output inductor unit comprises multiple differential-mode inductors, each connected to the positive and negative electrodes of the output rectifier unit. For example, the output inductor comprises two differential-mode inductors, each connected to the positive and negative electrodes of the output rectifier unit and to the output filter capacitor; this reduces output ripple and improves output voltage stability.

[0048] It should be noted that the inverter unit circuit can be an inverter circuit of 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 rectifier module circuit can also be a rectifier circuit of any topology. For example, the input rectifier module can be a three-phase PWM bridge rectifier circuit, a Vienna rectifier circuit, a three-phase uncontrolled rectifier circuit, etc.; the output rectifier can be a single-phase PWM half-bridge rectifier circuit, a single-phase PWM full-bridge rectifier circuit, a single-phase uncontrolled rectifier circuit, etc.

[0049] As a specific embodiment, the circuit diagram is as follows Figure 2 As shown, it 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.

[0050] Specifically, the input inductor unit is three two-phase coupled inductors; the input rectifier unit is two Vienna rectifiers; the inverter unit is two half-bridge three-level inverters; the transformer is a common core transformer; the output rectifier unit is two uncontrolled rectifier modules; and the output inductor unit is two differential mode inductors.

[0051] A two-phase coupled inductor has one input terminal and two output terminals, and three two-phase coupled inductors have three input terminals and six output terminals. The three input terminals are connected to the three-phase power respectively, and one output terminal of a two-phase coupled inductor is connected to the three-phase input terminal of the first Vienna rectifier, and the other output terminal is connected to the three-phase input terminal of the second Vienna rectifier; in this way, each two-phase coupled inductor is connected to all Vienna rectifiers at the same time.

[0052] The output ends of the two Vienna rectifiers are connected in parallel and then connected to the bus capacitor.

[0053] The input ends of the two half-bridge three-level inverters are connected in parallel to the bus capacitors, and the output ends are connected to the two primary ports of the common-core transformer respectively; the input ends of the two uncontrolled rectifier modules are connected to the two secondary ports of the common-core transformer respectively, and the output ends are connected in series and then connected to two differential-mode inductors. This not only reduces the size of the transformer but also further improves the power density of the charging power supply.

[0054] The output end of the two uncontrolled rectifier modules connected in series includes a positive and negative pole, a 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.

[0055] In this embodiment, the two half-bridge three-level inverters, the common-core transformer, and the two uncontrolled rectifier modules are connected in parallel before and in series afterwards. This connection reduces the requirements for transformer performance, allowing the use of transformers with smaller turns ratios, thereby increasing the output power of the charging power supply and doubling the output voltage range. Furthermore, because the input terminals of the half-bridge three-level inverters are connected in parallel, the input voltages of the input-side half-bridge three-level inverters are forced to be equal. The output terminals of the uncontrolled rectifier modules are connected in series, forcing the output currents of the uncontrolled rectifier modules to be equal. Consequently, the voltage regulation unit as a whole exhibits the characteristics of self-balanced input voltage and self-balanced output current.

[0056] In this embodiment, the output power borne by the Vienna rectifier, the half-bridge three-level inverter and the uncontrolled rectifier module is 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 improved, and the loss and voltage ripple on the output side can be reduced.

[0057] In another aspect, the present invention also provides a charging power supply power synthesis method. By adjusting the number of inverter modules and output rectifier modules in the charging power supply power synthesis system, the output power and output voltage range can be adjusted. The specific technical features are not detailed here.

[0058] In summary, the output power and output voltage of the charging power supply proposed in the present invention can be adjusted as needed, which not only meets the continuously growing battery capacity and charging power requirements of electrical equipment, but also has a small size, high power density, good versatility, easy upgrading, and simple and convenient maintenance.

[0059] It should be noted that for the aforementioned embodiments, for simplicity of description, they are all expressed as a series of action combinations, but those skilled in the art should be aware that this application is not limited by the order of the actions described, because according to this application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in this specification are all preferred embodiments, and the actions and modules involved are not necessarily required by this application.

[0060] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0061] In the several embodiments provided in this application, it should be understood that the disclosed methods or systems can be implemented in other ways. For example, the embodiments described above are merely illustrative, and the division of the units described is merely a logical functional division. In actual implementation, other division methods may be used, such as combining or integrating multiple units or components into another system, or ignoring or not implementing certain features.

[0062] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0063] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0064] If the 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, or the part that contributes to the existing technology, or all or part of the technical solution can be embodied in the form of a software product. This computer software product is stored in a memory and includes a number of instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of this application.

[0065] Those skilled in the art will appreciate that all or part of the various circuits in the above embodiments may be implemented by instructing related hardware through a program. The program may 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, or an optical disk.

[0066] The above is only an exemplary embodiment of the present disclosure and cannot be used to limit the scope of the present disclosure. That is, any equivalent changes and modifications made according to the teachings of the present disclosure are still within the scope of the present disclosure. After considering the specification and practicing the disclosure herein, those skilled in the art will easily think of the implementation scheme of the present disclosure. This application is intended to cover any variation, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary technical means in the art that are not recorded in the present disclosure. The description and examples are to be regarded as exemplary only, and the scope and spirit of the present disclosure are defined by the claims.

[0067] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, 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, they should be considered to be within the scope of this specification.

[0068] It will be easily understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A charging power synthesis system, characterized in that: The system 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; 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 is connected in parallel, and the output rectifier unit on the output side of the voltage regulating unit is connected in series; the inverter unit includes M inverter modules, and the output rectifier unit includes M output rectifier modules. The output ends of the M inverter modules are connected to the M primary input ports of the transformer, and the input ends of the M output rectifier modules are connected to the M secondary output ports of the transformer, and the M transformers share a set of magnetic cores. The system is used for charging, and the output power and output voltage range are adjusted by synchronously adjusting the number of inverter modules and rectifier modules; the maximum output voltage of the system is , the maximum output power is ; 、 They respectively represent the maximum output voltage and maximum output power when the inverter unit has only one inverter module and the output rectifier unit has only one rectifier module.

2. The charging power synthesis system according to claim 1, characterized in that: 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.

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

4. The charging power synthesis system according to claim 1, characterized in that: The input inductor 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 rectifier modules.

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

6. The charging power synthesis system according to claim 2, characterized in that: The output inductor unit is a plurality of differential mode inductors, which are respectively connected to the positive and negative electrodes of the output rectifier unit.

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

8. The charging power synthesis system according to claim 2, characterized in that: The inverter module is an inverter circuit of any topology, and the rectifier module is a rectifier circuit of any topology.

9. A charging power synthesis method using a charging power synthesis system according to any one of claims 1 to 8, characterized in that: The method comprises: adjusting the output power and the output voltage range by adjusting the number of inverter modules and output rectifier modules.

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