A method for optimizing dynamic current sharing of a parallel system

Abstract

The application relates to the technical field of parallel operation of inverters, and discloses a parallel operation system current sharing dynamic optimization method, which transmits loop information of each module through CAN communication, improves the current sharing effect when the modules join the system, effectively reduces the loop current problem, and significantly improves the overall reliability of the system, so that the application is suitable for wide range of popularization and application.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of parallel operation of inverters, and in particular to a method for optimizing dynamic current sharing of a parallel operation system. BACKGROUND

[0002] In practical applications, multiple inverters operating in parallel often face the problem of circulating current. This problem not only can cause a significant decrease in system output performance, leading to frequent failures, but also can cause serious damage to the entire system in extreme cases, affecting the stable operation and overall efficiency of the system. Therefore, using a suitable and reliable control method to effectively reduce the circulating current phenomenon between parallel inverters is of great significance to significantly enhance the stability and reliability of the entire system.

[0003] The traditional control strategy, i.e., the master-slave control method, usually relies on the master device to issue key information such as phase-locked phase, active power, and reactive power to each slave module through the CAN communication protocol. Each slave module then adjusts the amplitude and frequency of the output voltage according to the received information, combined with its own loop regulation mechanism, to achieve the purpose of balanced distribution of current. However, when a new module is added to the system, there is a large difference between the loop characteristics of the new module and the already stable running modules, and their dynamic response speed and adjustment ability are often unsatisfactory. In this adjustment process, it is easy to produce a large circulating current phenomenon, thereby posing a potential risk and threat to other normally running modules in the system.

[0004] Therefore, it is particularly important and urgent to improve and innovate the existing technology in view of the above technical bottlenecks and challenges.

[0005] The above information is given as background information only to assist with an understanding of the present disclosure, and does not determine or acknowledge whether any of the above is applicable as prior art with respect to the present disclosure. SUMMARY

[0006] The present application provides a method for optimizing dynamic current sharing of a parallel operation system to solve the problems in the prior art.

[0007] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0008] In a first aspect, the present application provides a method for optimizing dynamic current sharing of a parallel operation system, comprising:

[0009] S1, the master module aggregates the active power data InvActivePowerP of each slave module, and issues the average active power value InvActivePowerPAvg to each slave module;

[0010] S2, each of the slave modules respectively adjusts the given of the voltage droop loop output acting on the voltage loop according to the average active power value InvActivePowerPAvg and the active power data InvActivePowerP of itself, and adjusts the phase of the module based on the reactive power voltage droop control loop, so as to realize real-time control of the output voltage and current sharing of each of the slave modules;

[0011] S3, each of the slave modules respectively sends the data InvVoltDroopLoopOut of the current voltage droop loop output to the CAN bus through CAN communication, and the master module receives and summarizes the loop output data of each of the slave modules, eliminates the loop output data of the non-output module, performs average value calculation on the voltage droop loop output data of the output module, and sends the average value InvVoltDroopLoopOutAvg of the calculated voltage droop loop output data to each of the slave modules through CAN communication;

[0012] S4, each of the slave modules receives the average value InvVoltDroopLoopOutAvg of the voltage droop loop output data, and if the slave module is in a non-output state, divides the average value InvVoltDroopLoopOutAvg of the voltage droop loop output data by the instantaneous active power loop control parameter Kp of itself, as the initial value of the average active power loop output before module output.

[0013] S5, after the slave module originally in the non-output state is powered on and outputs, directly uses the result of dividing the average value InvVoltDroopLoopOutAvg of the voltage droop loop output data by the instantaneous active power loop control parameter Kp of itself as the initial value of the average active power loop integration and output.

[0014] Further, in the parallel system current sharing dynamic optimization method, before the S1, the method further comprises:

[0015] Constructing the active power-based voltage droop control loop of the master module and the slave module.

[0016] Further, in the parallel system current sharing dynamic optimization method, the S3 is specifically:

[0017] Each of the slave modules sends the data InvVoltDroopLoopOut output by the current voltage droop loop to the CAN bus at a fixed interval time through CAN communication, and the master module performs average value calculation on the voltage droop loop output data of the modules that have output after receiving and collecting the loop output data of each of the slave modules, and sends the average value InvVoltDroopLoopOutAvg of the voltage droop loop output data calculated to each of the slave modules through CAN communication.

[0018] In a second aspect, the present application provides a computer device comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the parallel system current sharing dynamic optimization method provided in the first aspect when executing the computer program.

[0019] In a third aspect, the present application provides a computer readable storage medium, which stores computer executable instructions, and the computer executable instructions are executed by a computer processor to implement the parallel system current sharing dynamic optimization method provided in the first aspect.

[0020] Compared with the prior art, the present application has the following beneficial effects:

[0021] The parallel system current sharing dynamic optimization method provided by the present application transmits the loop information of each module through CAN communication, which not only improves the current sharing effect when the module is added to the system, but also effectively reduces the loop current problem, thereby significantly improving the overall reliability of the system, and is suitable for wide range of popularization and application.

[0022] The present application has other characteristics and advantages, which will be apparent or will be described in detail in the accompanying drawings and subsequent specific embodiments incorporated herein, which together serve to explain the specific principles of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the accompanying drawings needed to be used in the embodiments or prior art description will be briefly introduced as follows. Obviously, the accompanying drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0024] Figure 1 is a flowchart of a parallel system current sharing dynamic optimization method provided by the first embodiment of the present application;

[0025] Figure 2is the voltage control loop schematic diagram of the master module and the slave module mentioned in embodiment one of the present application;

[0026] Figure 3 is the average active power outer loop initial value action position schematic diagram of the slave module mentioned in embodiment one of the present application;

[0027] Figure 4 is a structural schematic diagram of a computer device provided in embodiment two of the present application. DETAILED DESCRIPTION

[0028] In order to describe possible application scenarios, technical principles, specific schemes that can be implemented, purposes and effects that can be achieved, etc. of the present application in detail, the following will be described in detail in combination with specific embodiments listed and with reference to the drawings. The embodiments described in the present document are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, and cannot limit the protection scope of the present application.

[0029] In the present document, the term "embodiment" means that the specific features, structures or characteristics described in combination with the embodiment can be included in at least one embodiment of the present application. The term "embodiment" appearing at various positions in the specification does not necessarily refer to the same embodiment, and does not particularly limit the independence or association between other embodiments. In principle, in the present application, as long as there is no technical contradiction or conflict, each technical feature mentioned in each embodiment can be combined in any way to form a corresponding implementable technical solution.

[0030] Unless otherwise defined, the meanings of the technical terms used in the present document are the same as those commonly understood by those skilled in the art to which the present application belongs; the use of related terms in the present document is only for the purpose of describing specific embodiments, and is not intended to limit the present application.

[0031] In the description of the present application, the phrase "and / or" is a description of the logical relationship between objects, which means that there can be three relationships, for example, A and / or B, which means that there are three cases: A exists, B exists, and A and B exist at the same time. In addition, the character " / " in the present document generally represents that the associated objects before and after are a "or" logical relationship.

[0032] In the present application, terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual quantity, primary and secondary or order relationship between the entities or operations.

[0033] In the present application, the terms "comprise", "contain", "have", or other similar phrases as used in a clause are intended to encompass non-exclusive inclusion, and these phrases do not exclude the possibility that additional elements can be present in the process, method or product comprising the stated elements, so that the process, method or product comprising a series of elements can not only include those defined elements, but also include other elements not explicitly listed, or also include elements inherent to such process, method or product.

[0034] In the present application, the terms "greater than", "less than", "exceed" and the like are understood as not including the number itself; the terms "above", "below", "within" and the like are understood as including the number itself. In addition, in the description of the embodiments of the present application, the meaning of "multiple" is more than two (including two), and similar expressions related to "multiple" are also understood in this way, for example, "multiple groups", "multiple times" and the like, unless otherwise explicitly specified.

[0035] In the description of the embodiments of the present application, the spatial-related expressions used, such as "center", "lengthwise", "widthwise", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "vertical", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like, indicate the orientation or positional relationship based on the orientation or positional relationship shown in the specific embodiments or the drawings, and are only for the convenience of describing the specific embodiments of the present application or for the reader to understand, and do not indicate or imply that the indicated device or component must have a specific position, a specific orientation, or be constructed or operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0036] Unless otherwise explicitly specified or limited, in the description of the embodiments of the present application, the terms "mount", "connect", "connect", "fix", "set" and the like should be understood broadly. For example, the "connection" can be a fixed connection, or a detachable connection, or an integral setting; it can be a mechanical connection, or an electrical connection, or a communication connection; it can be directly connected, or indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art to which the present application belongs, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0037] Embodiment one

[0038] In view of the defects in the prior art described above, the applicant, based on many years of rich practical experience and professional knowledge in this field, and with the use of theories, actively researched and innovated to create a technology that can solve the defects in the prior art. After continuous research, design, and repeated trial samples and improvements, the present application was finally created, which has practical value.

[0039] Please refer to Figure 1 The flowchart of the parallel system current sharing dynamic optimization method provided by Embodiment One of the present application is shown. The method specifically includes the following steps:

[0040] S1, the master module aggregates the active power data InvActivePowerP of each slave module, and issues the average active power value InvActivePowerPAvg to each slave module.

[0041] It should be noted that this step is to achieve the balanced distribution of active power in the system. By collecting the active power data of all slave modules, the master module can understand the power distribution of the entire system.

[0042] Calculating and issuing the average active power value can guide the slave module to adjust its power output to achieve the overall power balance of the system.

[0043] In one embodiment of the present embodiment, before S1, the method further includes:

[0044] Constructing an active power-based voltage droop control loop for the master module and the slave module.

[0045] It should be noted that an active power-based voltage droop control loop needs to be constructed first, which is the basis for achieving active power regulation and voltage droop control. As shown in Figure 2 The active droop control loop output of the master module and the slave module is marked in red.

[0046] S2, each slave module adjusts the given of the voltage droop loop output to the voltage loop according to the average active power value InvActivePowerPAvg and its own active power data InvActivePowerP in real time, and adjusts the phase of the active power-based voltage droop control loop to achieve real-time control of the output voltage and current sharing of each slave module.

[0047] It should be noted that the slave module adjusts its voltage droop control output by comparing the difference between its own power and the average power to achieve real-time control of the output voltage and current sharing.

[0048] At the same time, combined with the voltage droop control of reactive power, the adjustment of the module phase can be realized, and the stability of the system and the balance of power distribution are further ensured.

[0049] S3, each slave module sends the data InvVoltDroopLoopOut output by the current voltage droop loop to the CAN bus through CAN communication, and the master module receives and collects the loop output data of each slave module, removes the loop output data of the non-output module, performs average value calculation on the voltage droop loop output data of the output module, and sends the average value InvVoltDroopLoopOutAvg of the voltage droop loop output data calculated to each slave module through CAN communication.

[0050] It should be noted that this step is to realize the sharing and averaging of the voltage droop control data at the system level. Through CAN communication, the voltage droop loop output data of all slave modules can be collected and processed by the master module.

[0051] The calculation and issuance of the average value can further guide the slave module to adjust its voltage droop control output, so as to realize more accurate voltage control and power distribution.

[0052] In an embodiment of the embodiment, S3 is specifically:

[0053] Each slave module sends the data InvVoltDroopLoopOut output by the current voltage droop loop to the CAN bus through CAN communication at a fixed interval, and the master module receives and collects the loop output data of each slave module, removes the loop output data of the non-output module, performs average value calculation on the voltage droop loop output data of the output module, and sends the average value InvVoltDroopLoopOutAvg of the voltage droop loop output data calculated to each slave module through CAN communication.

[0054] S4, each slave module receives the average value InvVoltDroopLoopOutAvg of the voltage droop loop output data, and if the slave module is in a non-output state, the average value InvVoltDroopLoopOutAvg of the voltage droop loop output data is divided by the instantaneous active power loop control parameter Kp of the slave module, as the initial value of the average active power loop output before module output. As shown in Figure 2 .

[0055] It should be noted that for the slave module in the non-output state, the average value is received and the initial value is calculated, which can prepare for the subsequent start-up output.

[0056] This initial value reflects the current average power state of the system, and helps the slave module quickly integrate into the system after startup, reducing the impact on other modules.

[0057] S5, the slave module originally in the no-output state outputs after starting, directly using the average value InvVoltDroopLoopOutAvg of the voltage droop loop output data divided by the instantaneous active power loop control parameter Kp of itself as the average active power loop integral and output initial value.

[0058] It should be noted that by directly using the calculated initial value, the slave module can more quickly adapt to the current power state of the system, reducing fluctuations and instability during the adjustment process.

[0059] This method speeds up the adjustment process of the average active power loop integral loop, reduces the impact on other modules, improves the dynamic performance of the system, and prevents potential impact on other modules when idle.

[0060] Although the terms module, current sharing, etc. are used more in this application, the possibility of using other terms is not excluded. The use of these terms is only to facilitate the description and explanation of the essence of the application; any additional limitation is contrary to the spirit of the application.

[0061] The parallel system current sharing dynamic optimization method provided by the embodiment of the application transmits loop information of each module through CAN communication, not only improves the current sharing effect when the module joins the system, but also effectively reduces the circulating current problem, thereby significantly improving the overall reliability of the system, and is suitable for wide range of popularization and application.

[0062] Embodiment two

[0063] Figure 4 A structural schematic diagram of a computer device is provided for the second embodiment of the application. Figure 4 A block diagram of an exemplary computer device 12 suitable for implementing embodiments of the present application is shown. Figure 4 The computer device 12 shown is merely an example and should not impose any limitation on the function and use range of the embodiments of the application.

[0064] As Figure 4 shown, the computer device 12 is in the form of a general-purpose computing device. The components of the computer device 12 can include but are not limited to one or more processors or processing units 16, system memory 28, and bus 18 connecting different system components (including system memory 28 and processing unit 16).

[0065] Bus 18 represents one or more of several bus architectures, including a memory bus or memory controller, a peripheral bus, a graphics acceleration port, a processor, or a local bus using any of the various bus architectures. For example, these architectures include, but are not limited to, the Industry Standard Architecture (ISA) bus, the Micro Channel Architecture (MAC) bus, the Enhanced ISA bus, the Video Electronics Standards Association (VESA) local bus, and the Peripheral Component Interconnect (PCI) bus.

[0066] Computer device 12 typically includes a variety of computer system readable media. These media can be any available media that can be accessed by computer device 12, including volatile and non-volatile media, removable and non-removable media.

[0067] System memory 28 may include computer system readable media in the form of volatile memory, such as random access memory (RAM) 30 and / or cache memory 32. Computer device 12 may further include other removable / non-removable, volatile / non-volatile computer system storage media. By way of example only, storage system 34 may be used to read and write non-removable, non-volatile magnetic media (…). Figure 4 Not shown; usually referred to as a "hard drive"). Although Figure 4 Not shown, a disk drive for reading and writing to a removable non-volatile disk (e.g., a "floppy disk") and an optical disk drive for reading and writing to a removable non-volatile optical disk (e.g., a CD-ROM, DVD-ROM, or other optical media) may be provided. In these cases, each drive may be connected to bus 18 via one or more data media interfaces. Memory 28 may include at least one program product having a set (e.g., at least one) of program modules configured to perform the functions of the embodiments of the present invention.

[0068] A program / utility 40 having a set (at least one) of program modules 42 may be stored, for example, in memory 28. Such program modules 42 include, but are not limited to, an operating system, one or more application programs, other program modules, and program data. Each or some combination of these examples may include an implementation of a network environment. Program modules 42 typically perform the functions and / or methods described in the embodiments of the present invention.

[0069] Computer device 12 can also communicate with one or more external devices 14 such as a keyboard, a pointing device, a display 24, etc.; one or more devices that enable a user to interact with computer device 12; and / or any devices (e.g., network card, modem, etc.) that enable computer device 12 to communicate with one or more other computing devices. Such communication can occur via Input / Output (I / O) interface(s) 22. Still yet, computer device 12 can communicate with one or more networks, such as a local area network (LAN), a general wide area network (WAN), and / or a public network (e.g., the Internet) via network adapter 20. As depicted, network adapter 20 communicates with the other components of computer device 12 via bus 18. It should be appreciated that although not shown, other hardware and / or software modules could be used in conjunction with computer device 12. Examples, include, but are not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data archival storage systems, etc. Figure 4

[0070] Processing unit 16 performs various function applications and data processing by running programs stored in system memory 28, such as implementing the parallel system flow dynamic optimization method provided by embodiments of the present application.

[0071] Embodiment Three

[0072] Embodiment Three of the present application provides a computer readable storage medium having computer executable instructions stored thereon, which when executed by a processor implement the parallel system flow dynamic optimization method provided by all embodiments of the present application.

[0073] Any combination of one or more computer readable medium can be employed. The computer readable medium can be a computer readable signal medium or a computer readable storage medium. A computer readable storage medium can be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of the computer readable storage medium include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In this document, the computer readable storage medium can be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device.

[0074] ​A computer readable signal medium can include a propagated data signal with computer executable code embodied therein, for example, in baseband or as part of a carrier wave. Such a propagated signal can take any of a variety of forms, including, but not limited to, electro-magnetic, optical, or any suitable combination thereof. A computer readable signal medium can be any computer readable medium that is not a computer readable storage medium and that can communicate, propagate or transport programming code.

[0075] Program code embodied on a computer readable medium can be transmitted using any appropriate medium, including but not limited to wireless, wire line, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

[0076] Computer program code for carrying out operations of the present application can be written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider).

[0077] Finally, it should be noted that the technical solutions of the above embodiments have been described in the specification and drawings of the present application, but the patent protection scope of the present application should not be limited thereto. Any equivalent structure or equivalent flow replacement or modification based on the essential concept of the present application, using the content described in the specification and drawings of the present application, and directly or indirectly implementing the technical solutions of the above embodiments in other related technical fields, etc., are all included in the patent protection scope of the present application.

Claims

1. A method for optimizing the dynamic current sharing of a parallel system, characterized in that, The method comprises: S1, the host module aggregates active power data InvActivePowerP of each slave module, and issues an average active power value InvActivePowerPAvg to each slave module; S2, each slave module respectively adjusts a given of a voltage droop loop output to a voltage loop according to the average active power value InvActivePowerPAvg and its own active power data InvActivePowerP, and adjusts a phase of the slave module based on reactive power to realize real-time control of an output voltage and current sharing of each slave module; S3, each slave module respectively sends data InvVoltDroopLoopOut of a current voltage droop loop output to a CAN bus through CAN communication, and after the host module receives and aggregates loop output data of each slave module, the loop output data of a non-output module is eliminated, average value calculation is performed on the voltage droop loop output data of an output module, and the average value InvVoltDroopLoopOutAvg of the calculated voltage droop loop output data is sent to each slave module through CAN communication; S4, each slave module receives the average value InvVoltDroopLoopOutAvg of the voltage droop loop output data, and if the slave module is in a non-output state, the average value InvVoltDroopLoopOutAvg of the voltage droop loop output data is divided by a self-instantaneous active power loop control parameter Kp to serve as an initial value of average active power loop output before module output; S5, after the slave module originally in the non-output state is powered on and outputs, the result of dividing the average value InvVoltDroopLoopOutAvg of the voltage droop loop output data by the self-instantaneous active power loop control parameter Kp is directly used as an average active power loop integral and output initial value.

2. The method according to claim 1, wherein, Before the S1, the method further comprises: Constructing an active power-based voltage droop control loop of the host module and the slave module.

3. The method of claim 1, wherein the dynamic load sharing is optimized by adjusting the power of each of the plurality of parallel machines. The S3 specifically comprises: Each slave module respectively sends data InvVoltDroopLoopOut of a current voltage droop loop output to a CAN bus through CAN communication at a fixed interval time, and after the host module receives and aggregates loop output data of each slave module, the loop output data of a non-output module is eliminated, average value calculation is performed on the voltage droop loop output data of an output module, and the average value InvVoltDroopLoopOutAvg of the calculated voltage droop loop output data is sent to each slave module through CAN communication.

4. A computer device comprising a memory and a processor, the memory storing a computer program, characterized in that, The processor executes the computer program to realize the parallel system current sharing dynamic optimization method according to any one of claims 1-3.

5. A computer-readable storage medium having stored thereon computer- executable instructions, wherein, The computer executable instructions are executed by the computer processor to implement the parallel system flow dynamic optimization method as claimed in any one of claims 1-3.

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