A parallel data interaction method for hybrid energy storage inverter

Abstract

The present invention discloses a parallel data interaction method for a hybrid energy storage inverter, which constructs a parallel system in which a host communicates with a plurality of slaves through a controller local area network bus, including the following steps: classifying the data types and addresses of the host and the slaves through standard frames; performing interactive communication of interactive data according to the standard frame classification, and the interactive data includes real-time interactive process data during the operation of the parallel system, and service data of the host management and the slave status. The present invention has good real-time performance, and the interaction is smooth and efficient. It can realize distributed communication and control between inverters, and is convenient for expansion and configuration.

Description

Technical Field

[0001] The invention relates to a parallel data interaction method for a hybrid energy storage inverter, belonging to the technical field of inverter grid connection. Background Art

[0002] The low-voltage energy storage inverter is composed of photovoltaic panels, batteries, and energy storage inverters. The hybrid energy storage inverter based on solar photovoltaic panels and batteries can make full use of photovoltaic energy. When the photovoltaic panel has sufficient energy, the excess energy can be stored in the battery. When the photovoltaic energy is insufficient, the stored energy can be released, which can meet the needs of self-generation and self-use to a certain extent and reduce the system's demand for grid-side energy.

[0003] However, with the increase of system load or the scenario of heavy system load in some parts, the low-power hybrid energy storage inverter can no longer meet the requirements, so the parallel system of hybrid energy storage inverter came into being.

[0004] Compared with the single-machine system, the parallel system has increased complexity in terms of system control. When the host is scheduled, it is necessary to realize data interaction with each inverter in the system.

[0005] In the traditional method, data packets are used for interactive communication. The data packets contain interactive information, command information, data feature information, status information, etc., which makes the data packet configuration cumbersome and difficult to read and write. Especially when the number of grid-connected inverters is large, packet loss and communication congestion may occur. On the one hand, the bandwidth requirements are relatively high, and on the other hand, the slow response causes control delays that affect system stability. Summary of the invention

[0006] The purpose of the present invention is to solve the deficiencies of the above-mentioned prior art. Aiming at the problem that the traditional interaction method has high requirements on the system bandwidth and is prone to communication delays and even failures, a parallel data interaction method for a hybrid energy storage inverter is proposed.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is:

[0008] A parallel data interaction method for a hybrid energy storage inverter is provided, which constructs a parallel system in which a host is connected to a plurality of slaves through a controller area network bus, and includes the following steps:

[0009] S1 classifies the data types and addresses of the host and slave through standard frames;

[0010] S2 performs interactive communication of interactive data according to standard frame classification. The interactive data includes real-time interactive process data during the operation of the parallel system, and service data of host management and slave status.

[0011] Preferably, in step S1, the standard frame includes a function segment, an address segment, and a message segment that are arranged at intervals, and the function segment, the address segment, and the message segment include at least three binary fields.

[0012] Preferably, in step S1, the function segment has a decimal function code corresponding to the interactive data; the address segment has a decimal address code corresponding to the host and the slave; the message segment has a decimal message code corresponding to the host and the slave;

[0013] The function codes include a host management function code, a slave status function code, a number of process data receiving function codes, and a number of process data sending function codes.

[0014] Preferably, in step S2, the process data is hexadecimal interactive data; the service data includes a management frame and a status frame, and the management frame and the status frame are hexadecimal data respectively.

[0015] Preferably, in step S2, the interactive data is single-frame data, and the maximum length of the single-frame data is 8 bytes.

[0016] The beneficial effects of the present invention are mainly reflected in:

[0017] 1. It has good real-time performance and the interaction is smooth and efficient.

[0018] 2. It can realize distributed communication and control among inverters, which is convenient for expansion and configuration. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Other features, objects and advantages of the present application will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0020] Figure 1 It is a flow chart of a parallel data interaction method of a hybrid energy storage inverter of the present invention.

[0021] Figure 2 It is a schematic diagram of a parallel system in a parallel data interaction method of a hybrid energy storage inverter of the present invention.

[0022] Figure 3 It is a schematic diagram of a standard frame in a parallel data interaction method of a hybrid energy storage inverter of the present invention. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] The present application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant inventions, rather than to limit the inventions. It should also be noted that, for ease of description, only the parts related to the relevant inventions are shown in the accompanying drawings. It should be noted that, in the absence of conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0025] The present invention provides a parallel data interaction method for a hybrid energy storage inverter, such as Figure 2 As shown, a parallel system is constructed in which a host communicates with several slaves via a controller area network bus. That is, the master-slave communication is constructed via the CAN bus. The communication construction via the CAN bus belongs to the prior art, and the protocol and communication are not described in detail.

[0026] In this case, if Figure 1 As shown, the parallel data interaction method includes: classifying the data types and addresses of the host and the slave through standard frames; performing interactive communication of interactive data according to the standard frame classification, and the interactive data includes real-time interactive process data during the operation of the parallel system, and service data of the host management and the slave status.

[0027] Specifically, the standard frame can divide the data ID, thereby realizing the data type and address classification of the master and slave machines, and realizing the communication interaction of the classified data.

[0028] The interactive data between the master and slave machines includes process data and service data. Through the division of standard frames, accurate data communication of corresponding addresses can be achieved, the real-time communication is guaranteed, and distributed communication control is easy.

[0029] Process data: covers the control data, feedback data, etc. of the master and slave machines during the operation of the parallel system, and data that requires real-time interaction.

[0030] Service data: refers to the data used by the host to control the slaves during the operation of the parallel system, as well as the status data of the slaves.

[0031] In a specific embodiment, Figure 3As shown, the standard frame includes a function segment, an address segment, and a message segment that are arranged at intervals, and the function segment, the address segment, and the message segment include at least three binary fields.

[0032] Of course, the binary field can be expanded according to the number of slaves and the number of process data items to meet the expansion and configuration requirements of distributed communication.

[0033] In a specific embodiment, the function segment has a decimal function code corresponding to the interactive data; the address segment has a decimal address code corresponding to the host and the slave; the message segment has a decimal message code corresponding to the host and the slave;

[0034] The function codes include host management function codes, slave status function codes, several process data receiving function codes, and several process data sending function codes.

[0035] More specifically, if Figure 3 As shown, the CAN standard frame ID has a total of 11 bits, with the first bit at the rightmost and the 11th bit at the leftmost. The 11-bit frame ID is divided as follows:

[0036] Function segment: occupies 9-11 bits, and can be combined into 8 types from 0 to 7 according to binary. The corresponding relationship of each function code is as follows:

[0037] Function segment (bit code) Function code (decimal) Functional Description 0 0 0 0 Service Data-Host Management Function Code 0 0 1 1 The first group of process object data sending (receiving) end function code 0 1 0 2 The first group of process object data receiving (sending) end function codes 0 1 1 3 The second group of process object data sending (receiving) end function codes 1 0 0 4 The second group of process object data receiving (sending) end function codes 1 0 1 5 The third group of process object data sending (receiving) end function codes 1 1 0 6 The third group of process object data receiving (sending) end function codes 1 1 1 7 Service data-slave status function code .

[0038] Address segment: occupies 5-8 bits, and can be combined into 6 types from 0 to 15 according to binary. Supports 1 host and up to 15 slave addresses. The host address is fixed to 0, and the address allocation in the method is as follows:

[0039] Address segment (bit code) Address code (decimal) Address Description 0 0 0 0 0 Host address (special) 0 0 0 1 1 Slave Address 1 0 0 1 0 2 Slave Address 2 0 0 1 1 3 Slave Address 3 0 1 0 0 4 Slave Address 4 0 1 0 1 5 Slave address 5 0 1 1 0 6 Slave Address 6 0 1 1 1 7 Slave address 7 1 0 0 0 8 Slave address 8 1 0 0 1 9 Slave address 9 1 0 1 0 10 Slave address 10 1 0 1 1 11 Slave address 11 1 1 0 0 12 Slave address 12 1 1 0 1 13 Slave address 13 1 1 1 0 14 Slave address 14 1 1 1 1 15 Slave address 15 .

[0040] Special: Address 0 is the host address. In this method, the host address must be fixed to 0. Under the service data management function code, the address code is 0, which means that all slaves are managed.

[0041] Message segment: occupies 1-4 bits, and can be combined into 6 types from 0 to 15 according to binary. Each machine supports a maximum of 16 message frames:

[0042] Message segment (bit code) Message code (decimal) Message Description 0 0 0 0 0 Message No. 0 0 0 0 1 1 Message No. 1 0 0 1 0 2 Message No. 2 0 0 1 1 3 Message No. 3 0 1 0 0 4 Message No. 4 0 1 0 1 5 News No. 5 0 1 1 0 6 News No. 6 0 1 1 1 7 News No. 7 1 0 0 0 8 News No. 8 1 0 0 1 9 News No. 9 1 0 1 0 10 News No. 10 1 0 1 1 11 News No. 11 1 1 0 0 12 News No. 12 1 1 0 1 13 News No. 13 1 1 1 0 14 News No. 14 1 1 1 1 15 News No. 15 .

[0043] The message number represents the encoding value of this message. The parties sending and receiving data send and receive message numbers according to the message number corresponding to the agreement. The transmitted data is the frame data corresponding to the frame ID.

[0044] In a specific embodiment, the process data is hexadecimal interactive data; the service data includes a management frame and a status frame, and the management frame and the status frame are hexadecimal data respectively. The interactive data is a single frame data, and the maximum length of the single frame data is 8 bytes.

[0045] ID combination:

[0046] Special case - 0x000: host management message frame, function code 0, address segment 0, representing the management of all slaves.

[0047] Process data frame:

[0048] The host sends frame ID-0x110: the first set of process data, message frame No. 0 sent to slave 1.

[0049] Slave sends frame ID-0x220: The first set of process data, message frame No. 0 sent by slave 2 to the host.

[0050] Service data frame: does not reflect the message number feature, the message number is 0.

[0051] Management message frame ID:

[0052] 0x010: The host's operation frame ID for slave No. 1.

[0053] …

[0054] 0x0F0: The host's operation frame ID for slave No. 15.

[0055] Status message frame ID:

[0056] 0x710: Status message frame sent by slave 1.

[0057] 0x7F0: Status message frame sent by slave 15.

[0058] Frame data:

[0059]

[0060] Process data, fill in the content according to actual usage.

[0061] Service data is divided into management frames and status frames. The data in the above table defines the frame data content currently used and can be supplemented as needed.

[0062] From the above description, we can see that it has good real-time performance, smooth and efficient interaction, can realize distributed communication and control between inverters, and is convenient for expansion and configuration.

[0063] The term "comprise" or any other similar term is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus / device that includes a list of elements includes not only those elements but also other elements not expressly listed, or also includes elements inherent to such process, method, article, or apparatus / device.

[0064] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A parallel data interaction method for a hybrid energy storage inverter, which constructs a parallel system in which a host communicates with a plurality of slaves via a controller area network bus, characterized in that The steps include: S1 classifies the data types and addresses of the host and slave through standard frames; S2 performs interactive communication of interactive data according to standard frame classification. The interactive data includes real-time interactive process data during the operation of the parallel system, and service data of host management and slave status.

2. According to claim 1, a method for parallel data interaction of a hybrid energy storage inverter is characterized in that: In the step S1, the standard frame includes a function segment, an address segment, and a message segment that are arranged at intervals, and the function segment, the address segment, and the message segment include at least three binary fields.

3. According to claim 2, a method for parallel data interaction of a hybrid energy storage inverter is characterized in that: In step S1, the function segment has a decimal function code corresponding to the interactive data; the address segment has a decimal address code corresponding to the host and the slave; the message segment has a decimal message code corresponding to the host and the slave; The function codes include a host management function code, a slave status function code, a number of process data receiving function codes, and a number of process data sending function codes.

4. According to claim 1, a method for parallel data interaction of a hybrid energy storage inverter is characterized in that: In the step S2, the process data is hexadecimal interactive data; the service data includes a management frame and a status frame, and the management frame and the status frame are hexadecimal data respectively.

5. According to claim 4, a method for parallel data interaction of a hybrid energy storage inverter is characterized in that: In the step S2, the interactive data is single-frame data, and the maximum length of the single-frame data is 8 bytes.

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