Configuration-free power distribution network multi-terminal T-connection double-ring line differential protection processing method

Abstract

The invention is suitable for the technical field of power system automation and relay protection, and provides a configuration-free power distribution network multi-terminal T-connection double-ring line differential protection processing method, which comprises the following steps: acquiring first parameters corresponding to a plurality of second interval devices input by a user, the second interval equipment is equipment, except the first interval equipment, in the interval equipment accessed to the power distribution network; the first parameter is used for indicating an interval device corresponding to the message data needing to be received; according to the first parameter, determining corresponding third interval equipment which needs to receive the vexation message data from a plurality of pieces of second interval equipment; obtaining first message data sent by a third interval device; and executing differential logic operation according to the first message data to obtain a calculation result. The method can support the access of more lines, is suitable for more complex T-connection lines of the power distribution network, is high in flexibility, and reduces the operation and maintenance cost.

Description

Technical Field

[0001] This application belongs to the field of power system automation and relay protection technology, and in particular relates to a method for differential protection of multi-terminal T-connected double-loop lines in distribution networks without configuration. Background Technology

[0002] With the development of digital communication and the improvement of chip processing capabilities, differential protection has become an important and effective form of protection. In distribution networks, multi-terminal T-connected transmission lines are widely used due to their advantages such as high line utilization, low investment cost, and small footprint. More and more regions are requiring distribution terminals to have multi-terminal T-connected differential functions.

[0003] Mainstream T-connector differential systems can generally only support 2 or 3 differential connections. When the number of access points exceeds 3, it is necessary to reconfigure or perform customized development, resulting in poor scalability and increased operation and maintenance costs. Summary of the Invention

[0004] This application provides a configuration-free differential protection method for multi-terminal T-connected double-loop lines in distribution networks. It can support more line access, adapt to more complex T-connected lines in distribution networks, and is highly flexible, reducing operation and maintenance costs.

[0005] In a first aspect, embodiments of this application provide a configuration-free differential protection method for multi-terminal T-connected double-loop lines in a distribution network, including:

[0006] The system obtains the first parameters corresponding to each of the multiple second interval devices input by the user. The second interval devices are devices other than the first interval devices among the interval devices connected to the power distribution network. The first parameters are used to indicate the interval device corresponding to the message data to be received.

[0007] The third interval device corresponding to the message data to be received is determined from multiple second interval devices based on the first parameter;

[0008] Receive the first message data sent by the third interval device;

[0009] Differential logic operations are performed based on the data in the first message to obtain the calculation result.

[0010] In this embodiment, the parameters of multiple first-interval devices connected to the distribution network, i.e., the first parameters, are firstly obtained. These parameters are open-configuration parameters, including the application identifier of the device and the subscription relationship parameters of the device, which can be adaptively configured according to the actual application. Based on the first parameters, multiple second-interval devices for the configured subscribed data can be determined. Then, the first message data sent by these second-interval devices is obtained. Finally, differential logic operations are performed on the message data to obtain the output result. By obtaining the adaptive application identifier and data subscription parameters configured for multiple first-interval devices, the second-interval devices for the subscribed data can be flexibly determined based on the parameters. This allows for dynamic adaptation to changes in the number of terminals in multi-terminal T-connection scenarios (such as expanding from 2 terminals to 1+ terminals) without relying on dedicated configuration tools or reinstalling files, and without relying on complex configuration file modifications or customized development. The above method significantly reduces the dependence on professional configuration tools, supports different line accesses, adapts to more complex distribution network T-connection lines, has high flexibility, and reduces operation and maintenance costs.

[0011] In one possible implementation of the first aspect, the distribution network includes a first ring network and a second ring network, wherein the application identifiers of the first bay devices included in the first ring network have different data ranges than those of the application identifiers of the first bay devices included in the second ring network; determining a third bay device from a plurality of second bay devices to send message data to the first bay device according to a first parameter includes:

[0012] The fourth interval device is determined from the first interval devices included in the first ring network based on the first parameter;

[0013] The fifth interval device is determined from the first interval devices included in the second ring network based on the first parameter;

[0014] The fourth and fifth interval devices are designated as the third interval devices.

[0015] In this embodiment, the fourth and fifth bay devices are accurately selected from the first bay devices of the first and second ring networks respectively by using the first parameter, and are determined as the third bay device. This realizes the dynamic matching and unified management of bay devices under the dual-ring network architecture, and provides accurate device objects for subsequent differential protection logic operations based on the third bay device. This effectively improves the accuracy and reliability of fault identification in the multi-terminal T-connection topology of the distribution network.

[0016] In one possible implementation of the first aspect, obtaining the first message data sent by the third interval device includes:

[0017] The first application identifier and the first target address corresponding to the third interval device are determined based on the first parameter;

[0018] The first message data sent by the third interval device is received based on the first application identifier and the first target address.

[0019] In this embodiment, the first application identifier and first target address of the third bay device are determined by the first parameter, and then the first message data sent by it is obtained. This realizes the automatic association of device communication parameters and accurate message acquisition under the dual-ring network architecture of the distribution network, and provides a standardized data interaction basis for subsequent protection functions such as data caching and differential operation, ensuring the accuracy and efficiency of information transmission between multi-terminal bay devices.

[0020] In one possible implementation of the first aspect, differential logic operations are performed based on the first message data to obtain a calculation result, including:

[0021] According to the first parameter, the first message data received from each third interval device is cached in the first buffer area corresponding to the first ring network or the second buffer area corresponding to the second ring network, so as to obtain the first subscription data corresponding to the first buffer area and the second subscription data corresponding to the second buffer area;

[0022] Differential logic operations are performed based on the first subscription data and the second subscription data to obtain the calculation result.

[0023] In this embodiment, the first message data of each third bay device is classified and cached in the corresponding cache area of ​​the dual-ring network by the first application identifier and the first target address to form the first and second subscription data. Then, differential logic operation is performed to obtain the calculation result, realizing the accurate classification and efficient utilization of sampled data under the dual-ring network architecture of the distribution network. This provides real-time and orderly electrical quantity vector data support for differential protection, ensuring the speed and accuracy of fault identification.

[0024] In one possible implementation of the first aspect, the calculation result includes a first result and a second result. Differential logic operations are performed based on the first subscription data and the second subscription data to obtain the calculation result, including:

[0025] Calculate the absolute value of the vector sum of the first subscribed data in the first cache region to obtain the first differential value corresponding to the first cache region;

[0026] Calculate the absolute value of the vector sum of the second subscribed data in the second cache region to obtain the second differential stream value corresponding to the second cache region;

[0027] Calculate the vector sum of the absolute values ​​of the first subscribed data in the first cache region to obtain the first braking current value corresponding to the first cache region;

[0028] Calculate the vector sum of the absolute values ​​of the second subscribed data in the second buffer region to obtain the second braking current value corresponding to the second buffer region;

[0029] Perform differential logic operations based on the first differential current value and the first braking current value to obtain the first result;

[0030] Differential logic operations are performed based on the second differential current value and the second braking current value to obtain the second result.

[0031] In this embodiment, the differential current value and braking current value are obtained by calculating the vector sum and absolute value of the subscribed data in the double-ring network buffer area, respectively. Then, differential logic operation is performed based on the two sets of values ​​to obtain the result. This realizes the accurate quantitative analysis of electrical quantities in the double-ring network of the distribution network, provides a scientific fault judgment basis for differential protection, and effectively improves the accuracy and reliability of fault identification of multi-terminal T-connected lines.

[0032] In one possible implementation of the first aspect, the method further includes:

[0033] Obtain the configuration file, which contains configuration information set according to the number of bay devices connected to the distribution network;

[0034] Obtain the second parameter; the second parameter includes the bay number corresponding to each bay device connected to the power distribution network.

[0035] The second application identifier and the second target address corresponding to the first interval device are determined based on the second parameter;

[0036] The second message data is generated based on the configuration file, the second application identifier, and the second destination address;

[0037] The second message data is sent to the power distribution network so that the sixth bay device receives the second message data; wherein, the sixth bay device is a bay device that subscribes to the second message data among the bay devices connected to the power distribution network.

[0038] In this embodiment, by obtaining the configuration file and interval number parameters, the device communication identifier is determined and a message is generated and sent to the subscribing device. This enables precise interaction of sampling data between distribution network interval devices based on a standardized protocol, providing a real-time and reliable data transmission channel for multi-terminal differential protection, and ensuring the speed and accuracy of fault detection under the dual-ring network architecture.

[0039] In one possible implementation of the first aspect, generating second message data based on the configuration file, the second application identifier, and the second destination address includes:

[0040] Generate the first sampled value message according to the configuration file;

[0041] The application identifier parameter in the first sampled value message is replaced with the second application identifier, and the target address parameter in the first sampled value message is replaced with the second target address to obtain the second message data.

[0042] In this embodiment, a second message data is obtained by generating a first sampled value message based on a configuration file and replacing the application identifier and target address parameters therein with a second application identifier and a second target address. This achieves dynamic adaptation and standardized encapsulation of communication parameters of distribution network bay equipment, ensuring that the sampled data can be accurately transmitted to the target equipment according to predetermined rules, and providing a reliable data interaction foundation for subsequent real-time services such as differential protection.

[0043] In one possible implementation of the first aspect, the method further includes:

[0044] Determine the configuration data of the second application identifier;

[0045] If the configuration data of the second application identifier is the second preset threshold, then sending the second message data to the third interval device is prohibited.

[0046] If the configuration data of the second application identifier is greater than the third preset threshold, an alarm will be triggered if the identifier parameter exceeds the limit; wherein, the third preset threshold is greater than the second preset threshold.

[0047] In this embodiment, by judging the configuration data of the second application identifier and executing the operation of prohibiting the sending of messages or the alarm operation of exceeding the limit according to the preset threshold (the second preset threshold and the third preset threshold greater than it), the legality verification and abnormal control of the communication identifier of the distribution network equipment are realized, effectively avoiding network conflicts caused by illegal identifiers and providing early warning of over-limit configuration, thus ensuring the stability and reliability of the communication network.

[0048] Secondly, embodiments of this application provide a terminal device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the differential protection processing method as described in any of the first aspects above.

[0049] Thirdly, embodiments of this application provide a computer-readable storage medium storing a computer program that, when executed by a processor, implements the differential protection processing method as described in any of the first aspects above.

[0050] Fourthly, embodiments of this application provide a computer program product that, when run on a terminal device, causes the terminal device to execute the differential protection processing method of any one of the first aspects described above.

[0051] It is understood that the beneficial effects of the second to fourth aspects mentioned above can be found in the relevant descriptions in the first aspect mentioned above, and will not be repeated here. Attached Figure Description

[0052] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0053] Figure 1 This is a flowchart illustrating the differential protection processing method provided in the embodiments of this application;

[0054] Figure 2 This is a schematic diagram of the T-connected multi-terminal differential dual-network architecture of the distribution network provided in the embodiments of this application;

[0055] Figure 3 This is a schematic diagram of the process for obtaining the first message data provided in an embodiment of this application;

[0056] Figure 4 This is a schematic diagram of parameter configuration provided in an embodiment of this application;

[0057] Figure 5 This is a flowchart illustrating the execution of differential logic operations provided in an embodiment of this application;

[0058] Figure 6 This is a schematic diagram of the process of sending message data provided in the embodiments of this application;

[0059] Figure 7 This is a schematic diagram of the process of generating message data provided in the embodiments of this application;

[0060] Figure 8 This is a flowchart of the adaptive configuration-free process provided in the embodiments of this application;

[0061] Figure 9 This is a schematic diagram of the structure of the terminal device provided in the embodiments of this application. Detailed Implementation

[0062] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0063] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0064] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0065] As used in this application specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if detected [the described condition or event]" may be interpreted, depending on the context, as meaning "once determined," "in response to determination," "once detected [the described condition or event]," or "in response to detection [the described condition or event]."

[0066] Furthermore, in the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0067] References to "one embodiment" or "some embodiments" in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized.

[0068] With the development of digital communication and the improvement of chip processing capabilities, differential protection has become an important and effective form of protection. In distribution networks, multi-terminal T-connected transmission lines are widely used due to their advantages such as high line utilization, low investment cost, and small footprint. More and more regions are requiring distribution terminals to have multi-terminal T-connected differential functions.

[0069] Mainstream T-connector differential systems can generally only support 2 or 3 differential connections. When the number of access points exceeds 3, it is necessary to reconfigure or perform customized development, resulting in poor scalability and increased operation and maintenance costs.

[0070] To address the aforementioned issues in the related technologies, this application provides a configuration-free differential protection method for multi-terminal T-connected double-ring lines in distribution networks. Based on the IEC61850 information model, a differential protection configuration file is generated. This file is generated according to the maximum number of access bays and downloaded to the distribution terminal. It sets its own (Application identifier, APPID) and the subscription bay's APPID. Based on the subscription parameters, it receives, summarizes, and calculates data to complete the differential protection logic judgment. This method can improve the configuration flexibility of T-connected multi-terminal differential protection, adapt to more operating environments, support up to 16 terminals and double-ring network operation, reduce on-site maintenance difficulty, and improve interoperability.

[0071] See Figure 1 This is a flowchart illustrating the differential protection processing method provided in an embodiment of this application. It is intended as an example and not a limitation. The method may include the following steps:

[0072] S101: Obtain the first parameters corresponding to each of the multiple second bay devices input by the user. The second bay devices are the devices other than the first bay devices among the bay devices connected to the power distribution network. The first parameters are used to indicate the bay device corresponding to the message data to be received.

[0073] In this embodiment, the term "interval device" refers to various distribution terminal devices (such as protection devices, measurement and control units, etc.) connected to the distribution network, and can be regarded as a basic node unit in the distribution network. The first interval device is a designated interval device (e.g., a master station device or a specific protection terminal) that serves as the core of data reception or protection logic in a multi-terminal T-connection network. The second interval device is the device subscribed to by the first interval device, and includes all other interval devices connected to the distribution network except for the "first interval device." The first parameter is a key parameter used to define whether the second interval device is subscribed to by the first interval device; essentially, it controls the data flow through binary switch quantities (0 / 1). Maintenance personnel can input the input parameters (i.e., the first parameter) of each second interval device through the distribution terminal human-machine interface or a remote monitoring system.

[0074] S102, determine the third interval device corresponding to the message data to be received from multiple second interval devices according to the first parameter.

[0075] In this embodiment of the application, when setting the first parameter, the operation and maintenance personnel can control whether the first interval device needs to receive the message data sent by the second interval device through a binary switch (0 / 1). The parameter = 1 corresponds to receiving the message data sent by the second interval device. The second interval device with the parameter set to 1 is set as the "third interval device". The parameter = 0 indicates that the message data sent by the interval device is not received, that is, the interval device is not subscribed to by other first interval devices.

[0076] Specifically, after the first interval device reads the input parameters set by the maintenance personnel, it iterates through all parameters and selects the second interval device with an input parameter of 1 as the third interval device to be subscribed to.

[0077] In one embodiment, the power distribution network includes a first ring network and a second ring network, wherein the application identifiers of the first bay devices included in the first ring network have different data ranges than those of the application identifiers of the first bay devices included in the second ring network; step S102 includes:

[0078] A fourth interval device is determined from the first interval devices included in the first ring network according to the first parameter; a fifth interval device is determined from the first interval devices included in the second ring network according to the first parameter; the fourth interval device and the fifth interval device are determined as the third interval device.

[0079] In the embodiments of this application, the power distribution network provided by this application is a topology composed of a first ring network (ring 1) and a second ring network (ring 2). The two differ in terms of interval numbering, application identifier, target address, etc., and together realize adaptive differential protection of multi-terminal T-connected lines.

[0080] See Figure 2 This is a schematic diagram of a T-connected multi-terminal differential dual-network architecture for a distribution network provided in an embodiment of this application, as shown below. Figure 2 As shown, both Ring 1 and Ring 2 are independent ring communication networks, which can carry different power distribution terminal equipment respectively. Ring 1 corresponds to devices (interval devices) A1, A2, A3 and A6, and Ring 2 corresponds to devices A4, A5 and A6. It supports the redundant design of the main line and the backup line. The dual-ring data subscription is independently controlled by the "Ring 1 / Ring 2 Interval Activation" parameter (0 / 1). The third interval device is determined according to its Ring 1 / Ring 2 interval activation parameter.

[0081] Traverse all interval parameters of ring 1. If "Ring 1 interval 1 input = 1", then the corresponding device interval number is 0x1, and this device becomes the fourth interval device. Traverse all interval parameters of ring 2. If "Ring 2 interval 5 input = 1", then the corresponding device interval number is 0x5, and this device becomes the fifth interval device. Merge the fourth interval device selected from ring 1 with the fifth interval device selected from ring 2 to form the third interval device set that sends message data to the first interval device.

[0082] For example, such as Figure 2 Device A6 is used as the first interval device. This device can determine the subscription device (third interval device) that needs to receive message data by traversing the first parameters. Figure 2It can be seen that interval devices A1, A2, and A3 are devices in ring 1 relative to A6, while interval devices A4 and A5 are devices in ring 2. Therefore, in the first parameter, A1, A2, and A3 in ring 1 are set to 1, and A4 and A5 in ring 1 are also set to 1. Since A7 does not belong to the ring network, it can be set to 0. Device A6 can identify the interval devices (fourth interval devices) in ring 1 that need to receive message data (A1, A2, and A3) and the interval devices (fifth interval devices) in ring 2 that need to receive message data (A4 and A5) by traversing the first parameter. Among them, devices A1, A2, and A3, as well as devices A4 and A5, are collectively referred to as the third interval devices.

[0083] In the above method, the fourth and fifth bay devices are accurately selected from the first bay devices of the first and second ring networks respectively according to the first parameter, and they are determined as the third bay devices. This realizes the dynamic matching and unified management of bay devices under the dual-ring network architecture, and provides accurate device objects for subsequent differential protection logic operations based on the third bay devices. This effectively improves the accuracy and reliability of fault identification in the multi-terminal T-connection topology of the distribution network.

[0084] S103, Receive the first message data sent by the third interval device.

[0085] In this embodiment of the application, the first message data includes sampled value data (such as current and voltage RMS values), the APPID corresponding to the current interval device, and parameter information such as the physical address and target address corresponding to the current interval device.

[0086] The first interval device, based on the first parameter, namely "Ring 1 / Ring 2 interval n input = 1", only receives the message data (first message data) from the corresponding interval device (third interval device).

[0087] In one embodiment, see Figure 3 This is a schematic diagram of the process for obtaining the first message data provided in an embodiment of this application, such as... Figure 3 As shown, step S102 includes:

[0088] S201, determine the first application identifier and first target address corresponding to the third interval device based on the first parameter.

[0089] In this embodiment, APPID is the identification information (first application identifier) ​​corresponding to the third interval device, the target address (first target address) is the physical address corresponding to the third interval device itself, and the first parameter is "ring 1 interval n input" or "ring 2 interval m input". When the value is 1, the corresponding interval device needs to send message data to the first interval device and become the third interval device. The APPID and target address of the power distribution terminal (third interval device) to be received can be determined according to the first parameter.

[0090] This application sets the local bay coding for the bay equipment in the power distribution network, as follows: Figure 2 The bay numbers A1-A7 shown are set to 1-7 respectively. This application allows for a maximum of 16 bay numbers to be connected to the distribution network. This application uses hexadecimal to define the range of bay numbers. The bay number range for ring 1 and ring 2 is 0x0-0x1FF. The starting address of the corresponding APPID is 0x4000, so the corresponding APPID = 0x4000 + number. Therefore, the APPID range is 0x4000-0x41FF. The target address format is 01-0C-CD-04-00-XX (XX represents the last two hexadecimal digits of the number).

[0091] This application overcomes the limitation of traditional technologies that only support 2-3 terminals, and is adapted to T-connection scenarios with up to 16 terminals in the distribution network (the common engineering scenario is a single ring with 8 terminals). For example, if the first parameter is: ring 1 bay 5 is connected, then the receiving APPID (first application identifier) ​​is 0x4000+0x5=0x4005, and the target address (first target address) is 01-0C-CD-04-00-05, which is the distribution terminal (third bay device).

[0092] See Figure 4 This is a schematic diagram of parameter configuration provided in the embodiments of this application, such as... Figure 4 As shown, the settings include the interval number of the interval device on its own side (the second parameter is detailed below) and its value range, as well as the input parameters of each interval device in the first ring network and the second ring network. Based on the above settings, when the interval number changes or the number of T-connectors changes, only the corresponding fixed parameters need to be modified, without the need for file configuration or customized modifications.

[0093] S202, receive the first message data sent by the third interval device according to the first application identifier and the first target address.

[0094] In this embodiment, the third bay device encapsulates the collected electrical quantity data (such as current and voltage sample values) into an SV message (first message data) in IEC 61850-9-2 format, then embeds it into an Ethernet message frame based on the ISO / IEC 8802-3 protocol, and then sends it to the network. The Ethernet frame contains the MAC address of the third bay device (e.g., the target address of ring 1 device is 01-0C-CD-04-00-XX); and the application identifier of the third bay device is set (e.g., APPID = 0x4005 for ring 1 bay 5). The message data is transmitted to the first bay device via a power distribution network communication network (e.g., fiber optic, Ethernet).

[0095] The first interval device receives all Ethernet frames through a hardware network card or software protocol. The application identifier and destination address obtained through the first parameter are filtered according to the following conditions: matching the first destination address of the third interval device (such as 01-0C-CD-04-00-XX) and matching the APPID of the third interval device, and receiving the first message data that meets the conditions.

[0096] In the above method, the first application identifier and the first target address of the third bay device are determined by the first parameter, and then the first message data sent by it is obtained. This realizes the automatic association of device communication parameters and accurate message acquisition under the dual-ring network architecture of the distribution network, and provides a standardized data interaction basis for subsequent protection functions such as data caching and differential operation, ensuring the accuracy and efficiency of information transmission between multi-terminal bay devices.

[0097] S104, perform differential logic operations based on the first message data to obtain the calculation result.

[0098] In this embodiment, the first message data is a sampled value (SV) message sent by the third bay device according to the IEC 61850-9-2 protocol. It contains real-time sampled values ​​of electrical quantities such as current and voltage of each line in the distribution network, as well as phase information. The accuracy and uniqueness of this data are ensured by the application identifier (APPID) and destination address in the Ethernet frame. After receiving this message data, the first bay device can perform differential logic calculations based on Kirchhoff's current law to accurately determine the fault area and output the calculation results.

[0099] In one embodiment, see Figure 5 This is a flowchart illustrating the execution of differential logic operations provided in an embodiment of this application, such as... Figure 5 As shown, step S104 includes:

[0100] S301, according to the first parameter, the first message data sent by each third interval device is cached in the first buffer area corresponding to the first ring network or the second buffer area corresponding to the second ring network, so as to obtain the first subscription data corresponding to the first buffer area and the second subscription data corresponding to the second buffer area.

[0101] In this embodiment, the received message data is buffered according to the first parameter, namely "ring 1 interval n input" or "ring 2 interval m input". If the received message data corresponds to ring 1, it is stored in the first buffer Valbuf1[n], and if the received message data corresponds to ring 2, it is stored in the second buffer Valbuf2[n] (wherein, each buffer stores information for a maximum of 16 intervals, i.e., the value range of n is {0,15}). Ultimately, the first buffer stores the valid subscription data of ring 1 (first subscription data), and the second buffer stores the valid subscription data of ring 2 (second subscription data), providing clear and well-structured data support for subsequent vector operations of differential protection.

[0102] S302, perform differential logic operation based on the first subscription data and the second subscription data to obtain the calculation result.

[0103] In the embodiments of this application, when performing differential operation based on the first and second subscription data, the current and voltage data of each input interval in the dual-ring network are first extracted, the differential current and braking current of ring 1 and ring 2 are calculated by Kirchhoff's law, and then the differential current and braking current are multiplied by the setting value and compared to determine whether it is an intra-zone fault, and the calculation result of the protection action is obtained.

[0104] In the above method, the first message data of each third bay device is classified and cached into the corresponding cache area of ​​the dual-ring network by using the first application identifier and the first target address to form the first and second subscription data. Then, differential logic operation is performed to obtain the calculation result, realizing the accurate classification and efficient utilization of sampled data under the dual-ring network architecture of the distribution network. This provides real-time and orderly electrical quantity vector data support for differential protection, ensuring the speed and accuracy of fault identification.

[0105] In one embodiment, step S302 includes:

[0106] Calculate the absolute value of the vector sum of the first subscribed data in the first buffer region to obtain the first differential current value corresponding to the first buffer region; calculate the absolute value of the vector sum of the second subscribed data in the second buffer region to obtain the second differential current value corresponding to the second buffer region; calculate the vector sum of the absolute values ​​of the first subscribed data in the first buffer region to obtain the first braking current value corresponding to the first buffer region; calculate the vector sum of the absolute values ​​of the second subscribed data in the second buffer region to obtain the second braking current value corresponding to the second buffer region; perform differential logic operation based on the first differential current value and the first braking current value to obtain the first result; perform differential logic operation based on the second differential current value and the second braking current value to obtain the second result.

[0107] In this embodiment of the application, Kirchhoff's current law is used to calculate the first differential current VecId1 (the magnitude of the vector sum of the currents flowing into the node) and the first braking current VecIr1 (the sum of the absolute values ​​of the currents in each branch) for the subscription data of ring 1. That is, the first differential current VecId1 = |VecIp[0] + VecIp[1] + ... + VecIp[n]|, and the first braking current VecIr1 = |VecIp[0]| + |VecIp[1]| + ... + |VecIp[n]|.

[0108] Similarly, the second differential current VecId2 = |VecIp[0] + VecIp[1] + ... + VecIp[n]|, and the second braking current VecIr2 = |VecIp[0]| + |VecIp[1]| + ... + |VecIp[n]|.

[0109] The differential current and braking current in each ring network are compared. If the first differential current value exceeds the product of the first braking current and the setting value (e.g., VecId1>K×VecIr1), an intra-zone fault in the first ring network is determined and a first result is output, triggering the trip logic. If the second differential current value exceeds the product of the second braking current and the setting value (e.g., VecId2>K×VecIr2), an intra-zone fault in the second ring network is determined and a second result is output, triggering the trip logic.

[0110] If the differential current does not exceed the limit, it indicates an external fault or normal operation. This calculation process utilizes subscription data from dual-ring independent buffers, combined with the fundamental component preprocessed by the Fourier algorithm, to ensure the accuracy of vector calculations, thereby enabling rapid fault identification and protection action decision-making for multi-terminal T-connected lines.

[0111] In the above method, the differential current value and braking current value are obtained by calculating the vector sum and absolute value of the subscribed data in the buffer area of ​​the double-ring network, and then the differential logic operation is performed based on the two sets of values ​​to obtain the result. This realizes the accurate quantitative analysis of electrical quantities in the double-ring network of the distribution network, provides a scientific basis for fault judgment for differential protection, and effectively improves the accuracy and reliability of fault identification of multi-terminal T-connected lines.

[0112] In one embodiment, see Figure 6 This is a schematic diagram of the process of sending message data provided in the embodiments of this application, such as... Figure 6 As shown, it includes:

[0113] S401, Obtain the configuration file. The configuration file contains configuration information set according to the number of bay devices connected to the distribution network.

[0114] In this embodiment of the application, the first interval device serves as a power distribution terminal that receives the first message data. The corresponding first interval device can also serve as a subscription device, which needs to collect real-time sampling values ​​of electrical quantities such as current and voltage of each line of the power distribution network and generate message data to send to other interval devices.

[0115] Specifically, each bay device in the distribution network, including the first bay device, needs to obtain a configuration file. This configuration file is generated by the SCD configuration tool. The configuration file is configured according to the maximum number of bays that the distribution terminal can receive. In this scheme, there are 16 bays. The configuration file contains the sampling channel information of each bay device, such as the number of current / voltage channels, sampling rate (e.g., 4000Hz), and A / D conversion accuracy. After receiving the configuration file, it is parsed and the analog current / voltage quantities are obtained through the current transformer, and then converted into digital sample values ​​by A / D conversion.

[0116] S402, obtain the second parameter; the second parameter includes the bay number corresponding to each bay device connected to the distribution network.

[0117] In this embodiment, the second parameter is the set of local bay numbers corresponding to each bay device connected to the distribution network. It uses hexadecimal encoding, ranging from 0x0 to 0x1FF (corresponding to decimal 0 to 511), and can cover the bay number values ​​corresponding to 16 bay devices in a dual-ring network. The local bay number is directly associated with the device's application identifier (APPID = 0x4000 + number) and target address (e.g., the target address of ring 1 device is 01-0C-CD-04-00-XX, where XX is the last two hexadecimal digits of the number). It is a core parameter for realizing device communication and differential protection configuration in a multi-terminal T-connection network. Bay devices can obtain manually configured local bay numbers through a local interface or a remote communication interface.

[0118] S403, determine the second application identifier and the second target address corresponding to the first interval device based on the second parameter.

[0119] In this embodiment of the application, the local bay number corresponding to the first bay device can be obtained according to the second parameter, and the target address (second target address) and APPID (second application identifier) ​​of the power distribution terminal (first bay device) can be determined according to the local bay number.

[0120] For example, if the local interval number of the interval device in ring 1 is 0x01, then its corresponding APPID = 0x4000 + 0x01 = 0x4001, and its corresponding target address is 01-0C-CD-04-00-01. The method for determining the APPID and target address of the interval device in ring 2 is the same as that in ring 1. The APPID value range is 0x0-0x1FF, and the target address value is 01-0C-CD-04-00-XX (XX is the last two digits of the hexadecimal number).

[0121] S404 generates second message data based on the configuration file, the second application identifier, and the second destination address.

[0122] In this embodiment of the application, the integrated configuration file and the application identifier and target address calculated based on the local interval number are used to generate message data that can be transmitted in the power distribution network according to the corresponding rules or protocols.

[0123] In one embodiment, see Figure 7 This is a schematic diagram of the process of generating message data provided in the embodiments of this application, such as... Figure 7 As shown, step S404 includes:

[0124] S501, Generate the first sampled value message according to the configuration file;

[0125] In this embodiment of the application, after the power distribution terminal reads the configuration file information, it splices the relevant information into an IEC61850-9-2 sampled value message (first sampled value message).

[0126] Specifically, after each interval device receives the configuration file, it parses it, extracts the sampling channel parameters, associates the physical sampling channels with their respective logical datasets ASDU, determines the order of data in the message, and then concatenates the parsed data into the sampled value message data of the IEC 61850-9-2 protocol.

[0127] S502, replace the application identifier parameter in the first sampled value message with the second application identifier, and replace the target address parameter in the first sampled value message with the second target address to obtain the second message data.

[0128] In this embodiment of the application, after generating the first sampled value message, it needs to be embedded in an Ethernet message (second message data) based on the ISO / IEC 8802-3 protocol (preset protocol), see [link to relevant documentation]. Figure 6 This is a schematic diagram of the structure of an Ethernet packet frame provided in an embodiment of this application, as shown below. Figure 6As shown, its structure is divided into 14 parts. Among them, the APPID and target address are strongly related to the power distribution terminal receiving / sending SV sampled value messages. Therefore, these parts are extracted as parameters for tuning. Thus, the APPID and target address of the first sampled value message are replaced.

[0129] Specifically, when embedding the first sampled value message into an Ethernet message, the power distribution terminal in this bay will set the "local APPID" according to the actual application scenario. For example, if "local APPID" = n, the power distribution terminal will replace the APPID parameter when reading the configuration file, replacing the APPID in the sampled value message structure with 0x4000+5, i.e., 0x400n. Similarly, the corresponding target address will be replaced with the address corresponding to this bay (the second target address). The replaced first sampled value message is then encapsulated to obtain an Ethernet frame, i.e., the second message data.

[0130] In the above method, the first sampled value message is generated according to the configuration file, and the application identifier and target address parameters in it are replaced with the second application identifier and the second target address to obtain the second message data. This realizes the dynamic adaptation and standardized encapsulation of communication parameters of distribution network bay equipment, ensuring that the sampled data can be accurately transmitted to the target equipment according to the predetermined rules, and providing a reliable data interaction foundation for subsequent real-time services such as differential protection.

[0131] S405, the second message data is sent to the distribution network so that the sixth bay device receives the second message data; wherein, the sixth bay device is the bay device that subscribes to the second message data among the bay devices connected to the distribution network.

[0132] In this embodiment of the application, the sixth interval device needs to set "Ring 1 / Ring 2 interval n input = 1" in the configuration file, where n is the interval number of the second message data sender. If the second message data is sent by Ring 1 interval 1 (interval number 0x1), then the sixth interval device needs to be configured with "Ring 1 interval 1 input = 1".

[0133] When receiving the second message data, the sixth interval device will filter the received message by parameters, including the second destination address (e.g., 01-0C-CD-04-00-01 for ring 1 device) and the second APPID field, i.e., the second application identifier (e.g., 0x4001).

[0134] In the above method, by obtaining the configuration file and bay number parameters, the device communication identifier is determined and a message is generated and sent to the subscribing device. This enables accurate interaction of sampling data between distribution network bay devices based on a standardized protocol, providing a real-time and reliable data transmission channel for multi-terminal differential protection, and ensuring the speed and accuracy of fault detection under the dual-ring network architecture.

[0135] In one embodiment, the method further includes the following steps before sending message data:

[0136] Determine the configuration data of the second application identifier; if the configuration data of the second application identifier is the second preset threshold, then prohibit the sending of the second message data to the third interval device; if the configuration data of the second application identifier is greater than the third preset threshold, then issue an alarm for exceeding the identifier parameter limit; wherein, the third preset threshold is greater than the second preset threshold.

[0137] In this embodiment of the application, since the application sets the range corresponding to the interval number as 0x0ˉ0x1FF (511), before the interval device sends the message data, it is necessary to determine the accuracy of the configuration of the application identifier corresponding to the interval number on this side. If the application identifier obtained according to the interval number on this side is 0 (second preset threshold), then sending message data to other devices is prohibited. If the maximum value is exceeded (third preset threshold, i.e. 511), an alarm is issued to indicate a configuration error.

[0138] In the above method, by judging the configuration data of the second application identifier and executing the operation of prohibiting the sending of messages or the alarm operation of exceeding the limit according to the preset threshold (the second preset threshold and the third preset threshold greater than it), the legality verification and abnormal control of the communication identifier of the distribution network equipment are realized, effectively avoiding network conflicts caused by illegal identifiers and providing early warning of over-limit configuration, thus ensuring the stability and reliability of the communication network.

[0139] See Figure 8 This is an adaptive configuration-free flowchart provided in the embodiments of this application, such as... Figure 8 As shown, the specific steps include:

[0140] 1. Set the current interval number m and set the subscription interval number m.

[0141] Maintenance personnel can enter the interval number m corresponding to each interval device and the interval number n corresponding to each subscription device in the terminal configuration interface.

[0142] 2. Generate application identifier and target address.

[0143] After reading the interval number, the system will automatically generate APPIDm and APPIDn for each interval device according to the set rules, and generate the corresponding target address for each interval device according to its respective APPID.

[0144] 3. APPIDm splices the SV sampling message data of this interval.

[0145] This interval device (the first interval device mentioned above) will assemble the IEC 61850-9-2 sampled value message according to the configuration file issued by the system, and then embed it into the Ethernet message frame based on the ISO / IEC 8802-3 protocol (second message data), and send it in the differential network.

[0146] 3. Receive SV sampled value messages of APPIDn in a polling manner at intervals.

[0147] The interval device sends sampled value message data and also receives sampled value message data (first message data) sent by the subscribing device APPIDn (the third interval device mentioned above). When receiving message data, it determines which ring network each subscribing device belongs to based on APPIDn. If it is ring 1, the received first message data is buffered in the first buffer area corresponding to ring 1; if it is ring 2, the received first message data is buffered in the second buffer area corresponding to ring 2. Finally, differential logic calculation is performed based on the data buffered in each buffer area to obtain the calculation result.

[0148] The above method is designed for a dual-ring scenario with a maximum of 16 intervals. However, actual engineering applications generally use a single-ring structure with 4 intervals or less. By making some parameters in the original configuration file available for tuning, remote operation and maintenance and debugging are facilitated. This reduces reliance on configuration tools; changes in application scenarios do not require re-outputting new configuration files, only adjustments to relevant setpoints are needed, eliminating the need to modify the configuration file again. Given the differences in configuration tools among various manufacturers, this significantly improves work efficiency for on-site maintenance personnel. It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of this application embodiment.

[0149] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0150] Figure 9 This is a schematic diagram of the structure of the terminal device provided in the embodiments of this application. For example... Figure 9 As shown, the terminal device 9 of this embodiment includes: at least one processor 90 ( Figure 9 (Only one is shown) a processor, a memory 91, and a computer program 92 stored in the memory 91 and executable on at least one processor 90. When the processor 90 executes the computer program 92, it implements the steps in any of the above-described differential protection processing method embodiments.

[0151] The terminal device can be a computing device such as a desktop computer, laptop, handheld computer, or cloud server. This terminal device may include, but is not limited to, a processor and memory. Those skilled in the art will understand that... Figure 9 This is merely an example of terminal device 9 and does not constitute a limitation on terminal device 9. It may include more or fewer components than shown, or combine certain components, or different components, such as input / output devices, network access devices, etc.

[0152] The processor 90 may be a Central Processing Unit (CPU), but it can also be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor.

[0153] In some embodiments, memory 91 may be an internal storage unit of terminal device 9, such as a hard disk or memory of terminal device 9. In other embodiments, memory 91 may be an external storage device of terminal device 9, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc., equipped on terminal device 9. Furthermore, memory 91 may include both internal storage units and external storage devices of terminal device 9. Memory 91 is used to store operating system, application programs, bootloader, data, and other programs, such as program code of computer programs. Memory 91 can also be used to temporarily store data that has been output or will be output.

[0154] This application also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, can implement the steps in the above-described method embodiments.

[0155] This application provides a computer program product that, when run on a terminal device, enables the terminal device to implement the steps described in the various method embodiments above.

[0156] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments of this application can be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. A computer-readable medium can include at least: any entity or device capable of carrying computer program code to a device / terminal equipment, a recording medium, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal, and a software distribution medium. Examples include USB flash drives, portable hard drives, magnetic disks, or optical disks. In some jurisdictions, according to legislation and patent practice, computer-readable media cannot be electrical carrier signals or telecommunication signals.

[0157] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0158] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0159] In the embodiments provided in this application, it should be understood that the disclosed apparatus / terminal devices and methods can be implemented in other ways. For example, the apparatus / terminal device embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0160] The units described as separate components may or may not be physically separate. 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 the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0161] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A differential protection processing method, characterized in that, The method is applied to a first bay device, which is any bay device connected to the power distribution network; the method includes: The system obtains first parameters corresponding to each of the multiple second interval devices input by the user. The second interval devices are devices other than the first interval device among the interval devices connected to the power distribution network. The first parameters are used to indicate the interval devices that the first interval device needs to receive message data from. Based on the first parameter, a third interval device corresponding to the message data that the first interval device needs to receive is determined from a plurality of second interval devices; Receive the first message data sent by the third interval device; Differential logic operations are performed based on the first message data to obtain the calculation result.

2. The differential protection processing method as described in claim 1, characterized in that, The power distribution network includes a first ring network and a second ring network. The application identifiers of the first interval devices included in the first ring network have different data ranges than those of the application identifiers of the first interval devices included in the second ring network. The step of determining the third interval device from among the plurality of second interval devices to send message data to the first interval device based on the first parameter includes: A fourth interval device is determined from the first interval devices included in the first ring network based on the first parameter; The fifth interval device is determined from the first interval devices included in the second ring network based on the first parameter; The fourth and fifth interval devices are identified as the third interval device.

3. The differential protection processing method as described in claim 2, characterized in that, The step of obtaining the first message data sent by the third interval device includes: The first application identifier and the first target address corresponding to the third interval device are determined based on the first parameter; The first message data sent by the third interval device is received based on the first application identifier and the first target address.

4. The differential protection processing method as described in claim 3, characterized in that, The step of performing differential logic operations based on the first message data to obtain the calculation result includes: According to the first parameter, the first message data sent by each of the third interval devices is cached in the first buffer area corresponding to the first ring network or the second buffer area corresponding to the second ring network to obtain the first subscription data corresponding to the first buffer area and the second subscription data corresponding to the second buffer area; The calculation result is obtained by performing differential logic operations based on the first subscription data and the second subscription data.

5. The differential protection processing method as described in claim 4, characterized in that, The calculation result includes a first result and a second result. The step of performing differential logic operations based on the first subscription data and the second subscription data to obtain the calculation result includes: Calculate the absolute value of the vector sum of the first subscribed data in the first cache region to obtain the first differential value corresponding to the first cache region; Calculate the absolute value of the vector sum of the second subscribed data in the second cache region to obtain the second differential stream value corresponding to the second cache region; Calculate the vector sum of the absolute values ​​of the first subscribed data in the first cache region to obtain the first braking current value corresponding to the first cache region; Calculate the vector sum of the absolute values ​​of the second subscribed data in the second cache region to obtain the second braking current value corresponding to the second cache region; Perform differential logic operations based on the first differential current value and the first braking current value to obtain a first result; Differential logic operations are performed based on the second differential current value and the second braking current value to obtain the second result.

6. The differential protection processing method as described in claim 1, characterized in that, The method further includes: Obtain the configuration file, which contains configuration information set according to the number of bay devices connected to the power distribution network; Obtain the second parameter; the second parameter includes the bay number corresponding to each bay device connected to the power distribution network. The second application identifier and the second target address corresponding to the first interval device are determined based on the second parameter; Generate second message data based on the configuration file, the second application identifier, and the second target address; The second message data is sent to the power distribution network so that the sixth bay device receives the second message data; wherein, the sixth bay device is a bay device that subscribes to the second message data among the bay devices connected to the power distribution network.

7. The differential protection processing method as described in claim 6, characterized in that, The step of generating the second message data based on the configuration file, the second application identifier, and the second target address includes: Generate the first sampled value message according to the configuration file; The application identifier parameter in the first sampled value message is replaced with the second application identifier, and the target address parameter in the first sampled value message is replaced with the second target address to obtain the second message data.

8. The differential protection processing method as described in claim 5, characterized in that, The method further includes: Determine the configuration data of the second application identifier; If the configuration data of the second application identifier is a second preset threshold, then sending the second message data to the third interval device is prohibited. If the configuration data of the second application identifier is greater than the third preset threshold, an alarm is triggered to indicate that the identifier parameter exceeds the limit; wherein the third preset threshold is greater than the second preset threshold.

9. A terminal device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method as described in any one of claims 1 to 8.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the method as described in any one of claims 1 to 8.

Images