Data transmission method and system among multiple devices in distribution network system

Abstract

The invention provides a data transmission method and system among multiple devices in a distribution network system. The method is applied to a target receiving device in a target distribution network system. The method comprises the following steps: receiving the number of sending frames of each sending device connected with a target receiving device; determining the current network pressure of the target receiving device according to the number of the sending frames of each sending device; and adjusting the number of received frames of the target receiving device according to the current network pressure, and replying an acknowledgement frame to each sending device, so that each sending device is used for adjusting the number of own sent frames based on the number of frames in the acknowledgement frame. The invention provides a method capable of adaptively adjusting the number of sending frames and the number of receiving frames, file transmission can be carried out at the maximum speed on the premise of ensuring network stability, and the speed of file synchronous transmission among multiple devices is improved on the basis, so that the problem of low speed of file synchronous transmission among multiple devices at the present stage is solved.

Description

Technical Field

[0001] The present invention relates to the field of power distribution equipment communication technology, and in particular to a data transmission method and system between multiple devices in a distribution network system. Background Art

[0002] There is often a need for file transfer between devices in the power distribution system, such as synchronization of historical files and recording files between distributed DTUs and distributed DTUs. For the sake of transmission efficiency and versatility, the current common way of transmission between devices is to use the IEC104 protocol of the network. IEC104 is an international standard protocol widely used in power systems, and IEC104 is also often used as a communication method between devices in the power distribution system.

[0003] Although the standard IEC104 has high file transfer efficiency due to its excellent protocol characteristics, it still takes a lot of time to transfer hundreds of megabytes of files between dozens of devices at the same time, and may even affect the normal operation of the equipment. Today's power grid has increasingly higher requirements for equipment efficiency, especially in an environment where file synchronization is required between multiple devices. The standard IEC104 protocol can no longer meet the demand for fast transmission. Too slow a transmission speed will lead to a decrease in equipment performance and stability. Summary of the invention

[0004] The embodiment of the present invention provides a method and system for data transmission between multiple devices in a distribution network system, so as to solve the problem of slow file synchronization transmission speed between multiple devices at present.

[0005] In a first aspect, an embodiment of the present invention provides a method for data transmission between multiple devices in a distribution network system, which is applied to a target receiving device in a target distribution network system; the method comprises:

[0006] Receive the number of transmission frames of each transmission device connected to the target receiving device;

[0007] Determine the current network pressure of the target receiving device based on the number of frames sent by each sending device;

[0008] According to the current network pressure, the number of received frames of the target receiving device is adjusted, and a confirmation frame is replied to each sending device, so that each sending device is used to adjust its own sending frame number based on the frame number in the confirmation frame.

[0009] In a possible implementation, adjusting the number of frames received by the target receiving device according to the current network pressure includes:

[0010] If the current network pressure is greater than the network pressure threshold of the target receiving device, the number of received frames of the target receiving device is reduced according to the first preset value, and the process returns to the step of determining the current network pressure of the target receiving device according to the number of sent frames of each sending device;

[0011] If the current network pressure is equal to the network pressure threshold of the target receiving device, the current number of received frames of the target receiving device is kept unchanged, and the process returns to the step of determining the current network pressure of the target receiving device according to the number of sent frames of each sending device;

[0012] If the current network pressure is less than the network pressure threshold of the target receiving device, the number of received frames of the target receiving device is increased according to the first preset value, and the step of determining the current network pressure of the target receiving device according to the number of sent frames of each sending device is returned.

[0013] In a possible implementation, the target receiving device uses the extended IEC104 protocol to receive the file.

[0014] In a possible implementation, the extended IEC104 protocol is obtained by increasing the length of each frame of the IEC104 message in the standard IEC104 protocol;

[0015] The target receiving device receives each IEC104 message frame according to the preset byte length through the extended IEC104 protocol.

[0016] In a possible implementation, determining the current network pressure of the target receiving device according to the number of frames sent by each sending device includes:

[0017] For any sending device, the current characteristic value of the sending device is calculated according to the current number of received frames of the target receiving device; the current network pressure of the sending device is calculated according to the current characteristic value;

[0018] The sum of the current network pressures corresponding to the sending devices connected to the target receiving device is used as the current network pressure of the target receiving device.

[0019] In a second aspect, an embodiment of the present invention provides a method for data transmission between multiple devices in a distribution network system, which is applied to any sending device connected to a target receiving device in a target distribution network system as provided in the first aspect; the method comprises:

[0020] Receive the confirmation frame replied by the target receiving device;

[0021] According to the frame quantity in the confirmation frame of the target receiving device, the sending frame quantity of each sending device is adjusted, and the adjusted sending frame quantity is sent to the target receiving device.

[0022] In a possible implementation, adjusting the number of frames sent by the sending device according to the number of frames in the confirmation frame of the target receiving device includes:

[0023] If the number of frames in the confirmation frame of the target receiving device increases, the number of frames sent by each sending device is increased according to the second preset value, and the process returns to the step of adjusting the number of frames sent by each sending device according to the number of frames in the confirmation frame of the target receiving device;

[0024] If the number of frames in the confirmation frame of the target receiving device remains unchanged, the current number of frames sent by each sending device remains unchanged, and the process returns to the step of adjusting the number of frames sent by each sending device according to the number of frames in the confirmation frame of the target receiving device;

[0025] If the number of frames in the confirmation frame of the target receiving device decreases, the number of sending frames of each sending device is reduced according to the second preset value, and the step of adjusting the number of sending frames of each sending device according to the number of frames in the confirmation frame of the target receiving device is returned.

[0026] In a possible implementation, if the current network pressure is equal to the network pressure threshold of the target receiving device, the method further includes:

[0027] Receive the number of sending devices connected to the target receiving device sent by the target receiving device;

[0028] If the number of sending devices connected to the target receiving device at the current moment increases, the number of sending frames of the sending device connected to the target receiving device at the previous moment is reduced according to the third preset value to obtain the number of sending frames of each sending device at the next moment;

[0029] If the number of sending devices connected to the target receiving device at the current moment remains unchanged, the number of sending frames of the sending device connected to the target receiving device remains unchanged;

[0030] If the number of sending devices connected to the target receiving device at the current moment decreases, the number of sending frames of the sending devices connected to the target receiving device at the previous moment is increased according to the third preset value to obtain the number of sending frames of each sending device at the next moment.

[0031] In a possible implementation, the method further includes:

[0032] Each sending device uses the extended IEC104 protocol to send files;

[0033] The extended IEC104 protocol is obtained by increasing the length of each frame of the IEC104 message in the standard IEC104 protocol;

[0034] Each sending device transmits each IEC104 message frame according to the preset byte length through the extended IEC104 protocol.

[0035] In a third aspect, an embodiment of the present invention provides a data transmission system between multiple devices in a distribution network system, the system comprising at least one target receiving device, and at least two sending devices connected to the at least one target receiving device;

[0036] Wherein, at least one target receiving device is used to implement the method provided in any one of the first aspects;

[0037] The sending device is used to implement the method provided in any one of the second aspects.

[0038] The embodiment of the present invention provides a data transmission method and system between multiple devices in a distribution network system. The embodiment of the present invention provides a method capable of adaptively adjusting the number of sent frames and the number of received frames, which can perform file transmission at the maximum speed under the premise of ensuring network stability, and on this basis, improve the speed of synchronous file transmission between multiple devices to solve the problem of slow synchronous file transmission between multiple devices at this stage. Specifically, the embodiment of the present invention monitors the number of sent frames of each sending device connected to the target receiving device in real time to determine the current network pressure based on the number of sent frames of each sending device. Taking the current network pressure as the judgment condition, when the current network pressure is large, it means that the network pressure caused by the current number of continuous received frames of the target receiving device has exceeded the network pressure that the target receiving device can bear, and continuing to transmit with such a number of sent and received frames will cause network collapse, so it is necessary to reduce the number of received frames of the target receiving device and the number of sent frames of the sending device. Similarly, when the current network pressure is small, it means that the file transmission speed is not the fastest. Therefore, by synchronously increasing the current number of received frames of the target receiving device and the number of sent frames of each sending device, it is ensured that the file is transmitted at the maximum speed under the condition of network stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or related technical descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0040] Figure 1 is a flow chart for implementing a data transmission method between multiple devices in a distribution network system provided by an embodiment of the present invention;

[0041] Figure 2 is a flowchart of an implementation of a target receiving device adjusting the number of received frames provided by an embodiment of the present invention;

[0042] Figure 3 is a flow chart for implementing a data transmission method between multiple devices in a distribution network system provided by an embodiment of the present invention;

[0043] Figure 4 is a flowchart of an implementation of adjusting the number of sent frames by a sending device provided in an embodiment of the present invention;

[0044] Figure 5 It is a system architecture diagram of a data transmission system between multiple devices in a distribution network system provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0045] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present invention.

[0046] In order to make the purpose, technical solutions and advantages of the present invention more clear, specific embodiments will be described below in conjunction with the accompanying drawings.

[0047] Example 1:

[0048] See also Figure 1 , Figure 1 1 is a flowchart of a method for transmitting data between multiple devices in a distribution network system provided by an embodiment of the present invention, and the method is applied to a target receiving device in a target distribution network system. Specifically, the method may include:

[0049] Step 110: Receive the number of transmission frames of each transmission device connected to the target receiving device.

[0050] In this embodiment, there are at least two sending devices connected to the target receiving device. When outputting a file, each sending device will synchronously send its own corresponding number of continuous sending frames (i.e. k, hereinafter referred to as the number of sending frames) that does not require confirmation from the receiving party to the target receiving device.

[0051] In this embodiment, the target receiving device can use the standard IEC104 protocol to receive files. The method provided in this embodiment can be used to transmit I frames in the standard IEC104 protocol, that is, also used to transmit information frames, wherein the information frames are used to transmit specific communication data.

[0052] Step 120: Determine the current network pressure of the target receiving device according to the number of frames sent by each sending device.

[0053] In this embodiment, a position-based closed-loop control algorithm is configured in the target receiving device, and the algorithm is also called a proportional-integral-differential (PID) algorithm.

[0054] In this embodiment, the target receiving device can calculate the current network pressure and its own processing capacity in real time. Among them, its own processing capacity is also the upper limit of the network frames that the target receiving device can process simultaneously. The current network pressure is used to characterize the relationship between the unprocessed network frames and its own processing capacity. When the unprocessed network frames are large, it will cause frame loss; theoretically, when the target receiving device is running stably, there is the following relationship between the number of network frames that can be processed and the upper limit of the network frames:

[0055] a=0.8m

[0056] Where a is the number of network frames that can be processed during stable operation, and m is the upper limit of the network frame.

[0057] In this case the target receiving device has the fastest file transfer speed.

[0058] Optionally, the current network pressure can be calculated as follows:

[0059] For any sending device, the current characteristic value of the sending device is calculated according to the current number of received frames of the target receiving device; and the current network pressure of the sending device is calculated according to the current characteristic value.

[0060] The sum of the current network pressures corresponding to the sending devices connected to the target receiving device is used as the current network pressure of the target receiving device.

[0061] In this embodiment, due to the restrictions of the IEC104 protocol, generally, there is the following relationship between the upper limit of the receiving frame of the target receiving device and the number of the sending frames it receives: the upper limit of the receiving frame is greater than the sending frame-4.

[0062] In this embodiment, for any sending device, in order to ensure the transmission rate, based on the relationship between the upper limit of the receiving frame of the target receiving device and the number of the sending frames it receives, the current characteristic value of the sending device can be defined as equal to the current number of received frames + 4, that is:

[0063] p i =w i +4

[0064] Among them, p i is the current eigenvalue; w i The current number of received frames.

[0065] Accordingly, for the sending device, the current network pressure and its corresponding current characteristic value have the following relationship:

[0066]

[0067] e(t)=0.8m(t)-r(t)

[0068] Where e(t) is the network pressure factor for stable file transmission at time t; m(t) is the upper limit of the network frames that the target receiving device can process simultaneously; r(t) is the number of unprocessed network frames.

[0069] In order to ensure stable transmission, in theory, the number of frames sent by each device is equal to the number of frames received by the target receiving device. Based on this theory, the current network pressures corresponding to each sending device connected to the target receiving device can be summed up, and the summed current network pressures corresponding to each sending device can be used as the current network pressure of the target receiving device.

[0070] Step 130: According to the current network pressure, the number of received frames of the target receiving device is adjusted, and a confirmation frame is replied to each sending device, so that each sending device adjusts its own number of sent frames based on the number of frames in the confirmation frame.

[0071] In this embodiment, based on the IEC104 protocol, after receiving frame data each time, the target receiving device will reply a confirmation frame to the corresponding sending device, and the confirmation frame includes a frame sequence number corresponding to the received frame data. If the receiving sequence number in the confirmation frame replied by the target receiving device is 2, it means that the target receiving device has received the two frame messages 1 and 2.

[0072] In this embodiment, when the current network pressure does not match the network pressure threshold of the target receiving device, it is necessary to adjust the maximum number of frames that the target receiving device can receive without replying to the confirmation frame, hereinafter referred to as the number of received frames, that is, the w value. After the number of received frames changes, the corresponding number of sent frames will also change synchronously. The following is a description of how to adjust the number of received frames of the target receiving device according to the network pressure, and how to adjust the number of sent frames of the corresponding sending device through relevant embodiments.

[0073] In an optional embodiment, adjusting the number of received frames of the target receiving device according to the current network pressure in step 130 may include:

[0074] If the current network pressure is greater than the network pressure threshold of the target receiving device, the number of received frames of the target receiving device is reduced according to the first preset value, and the step of determining the current network pressure of the target receiving device according to the number of sent frames of each sending device is returned.

[0075] If the current network pressure is equal to the network pressure threshold of the target receiving device, the current number of received frames of the target receiving device is kept unchanged, and the step of determining the current network pressure of the target receiving device according to the number of sent frames of each sending device is returned.

[0076] If the current network pressure is less than the network pressure threshold of the target receiving device, the number of received frames of the target receiving device is increased according to the first preset value, and the step of determining the current network pressure of the target receiving device according to the number of sent frames of each sending device is returned.

[0077] Figure 2 The following is a flowchart of the target receiving device adjusting the number of received frames provided by the embodiment of the present invention. Figure 2 This embodiment is described. Figure 2 The w in it is the current number of received frames of the target receiving device.

[0078] In this embodiment, the network stress threshold of the target receiving device is inherent data of the target receiving device, and the network stress thresholds of different target receiving devices are different.

[0079] In this embodiment, if the current network pressure is greater than the network pressure threshold of the target receiving device, it means that the number of network frames processed simultaneously by the target receiving device does not satisfy a=0.8m, that is, a>0.8m. In this case, not only the transmission speed is slow, but also network fluctuations may be caused, and the network stability cannot be maintained. Therefore, it is necessary to reduce the current number of received frames of the target receiving device.

[0080] In this embodiment, when the current number of received frames of the target receiving device is reduced, it can be reduced according to a first preset value; wherein the first preset value can be a lower limit value of the number of received frames of the target receiving device, or can be set according to actual needs. After the number of received frames of the target receiving device is reduced according to the first preset value, in order to prevent frame loss, each sending device will reduce its own number of sent frames according to the number of frames in the confirmation frame.

[0081] In addition, in this embodiment, when the current number of received frames of the target receiving device is the lower limit of the number of received frames that can be adjusted by the target receiving device, and the current network pressure is still greater than the network pressure threshold of the target receiving device, it means that a system failure has occurred. At this time, the target receiving device issues an alarm to provide relevant personnel with timely maintenance.

[0082] In this embodiment, if the current network pressure is equal to the network pressure threshold of the target receiving device, it means that the transmission speed is optimal under the current network pressure and no adjustment is required.

[0083] In this embodiment, if the current network pressure is less than the network pressure threshold of the target receiving device, it means that the number of network frames processed simultaneously by the target receiving device does not satisfy a=0.8m, that is, a<0.8m. In this case, although the network is in a stable state, the transmission speed is not optimal. Therefore, it is necessary to increase the current number of received frames of the target receiving device to maintain the maximum transmission speed when the current network pressure is not greater than the network pressure threshold of the target receiving device.

[0084] At this time, the current number of received frames of the target receiving device may be increased according to the first preset value, and after the increase, each sending device will increase its own number of sent frames according to the number of frames in the confirmation frame.

[0085] In this embodiment, since the method provided in this embodiment has the functions of real-time monitoring and adaptive adjustment, after each monitoring and adjustment is completed, it is necessary to recalculate the adjusted network pressure to determine how to adjust the number of received frames of the target receiving device at the next moment until the file transfer is completed.

[0086] It can be seen that this embodiment provides a method for adaptively adjusting the number of sent frames and the number of received frames, which does not require adjustment of the transmission protocol, is easy to operate, and can save costs. In addition, it can also transfer files at the maximum speed while ensuring network stability.

[0087] In summary, the method provided in Example 1 is applied to the target receiving device and can improve the transmission speed of the information frame. The following Example 2 provides a method that is applied to the target receiving device and can improve the transmission speed of the message frame.

[0088] Example 2:

[0089] In an optional embodiment, the target receiving device may adopt the extended IEC104 protocol to receive the file.

[0090] Accordingly, the extended IEC104 protocol is obtained by increasing the length of each frame of the IEC104 message in the standard IEC104 protocol.

[0091] The target receiving device receives each IEC104 message frame according to the preset byte length through the extended IEC104 protocol.

[0092] In this embodiment, when the target receiving device adopts the standard IEC104 protocol to receive files, the maximum size of each frame is 255 bytes, and the file data that can be included is only about 230 bytes. For a 1M file, at least 2560 frames are required to transmit it. In addition to the limitations of the network port rate and the device CPU processing power, so many network frames will take a lot of time. If a target receiving device synchronizes multiple sending devices at the same time, the transmission time will also increase exponentially.

[0093] Taking this into consideration, this embodiment increases the length of each frame of IEC104 message in the standard IEC104 protocol, and increases the 1 byte representing the frame length in the standard IEC104 protocol to 2 bytes. In this way, the theoretical length of a frame of IEC104 message can be increased from 255 bytes to 65535 bytes, but due to the maximum transmission unit (MTU) limit of the network, too long data will also be sent in packets in the network, increasing the transmission burden and affecting resource utilization.

[0094] Therefore, when the target receiving device uses the extended IE104 protocol to receive files, it is necessary to limit the length of each frame byte, that is, it is necessary to transmit the message frame according to the preset byte length. In this embodiment, based on the MTU limitation and in order to ensure the maximum transmission rate, the preset byte length can be 1500 bytes. This can ensure that each frame of the network packet sends as much file data as possible.

[0095] In addition, it should be noted that in this embodiment, the extended IEC104 protocol only improves the message frame for transmitting files. When the target receiving device adopts the extended IE104 protocol for file reception, other I frames (network frames), S frames (monitoring frames) and U frames (control frames) are still processed according to the message frame format of the standard IEC104 protocol to be compatible with the existing IEC104 standard protocol.

[0096] Therefore, in actual application, the extended IE104 protocol can be applied to the method provided in Example 1. Of course, the method in Example 1 can also be implemented based on the standard IE104 protocol, while the method provided in Example 2 requires the use of the extended IE104 protocol for file transfer.

[0097] The above examples 1 and 2 are used to illustrate how the target receiving device in the target distribution network system receives data during data transmission. The following examples 3 and 4 illustrate how the sending device in the target distribution network system sends data during data transmission.

[0098] Figure 3is a flow chart of the implementation of the data transmission method between multiple devices in the distribution network system provided by the embodiment of the present invention; Figure 3 As shown, the method can be applied to any sending device connected to the target distribution network system provided in Example 1 or Example 2, and the method may include:

[0099] Step 210: Receive a confirmation frame replied by the target receiving device.

[0100] In this embodiment, each sending device connected to the target receiving device can receive the confirmation frame replied by the target receiving device in real time, and determine the number of frames received by the target receiving device this time according to the number of frames in the confirmation frame.

[0101] Step 220: According to the number of frames in the confirmation frame of the target receiving device, the number of transmission frames of each sending device is adjusted, and the adjusted number of transmission frames is sent to the target receiving device.

[0102] In this embodiment, when performing file transfer, each sending device will adjust its corresponding number of continuous frames sent without receiving party confirmation (i.e., k, hereinafter referred to as the number of sent frames) according to the w value of the receiving device. When the number of received frames of the target receiving device changes, the number of sent frames of the corresponding sending device also changes.

[0103] In an optional embodiment, adjusting the number of frames sent by the sending device according to the number of frames in the confirmation frame of the target receiving device in step 220 may include:

[0104] If the number of frames in the confirmation frame of the target receiving device increases, the number of sending frames of each sending device is increased according to the second preset value, and the step of adjusting the number of sending frames of each sending device according to the number of frames in the confirmation frame of the target receiving device is returned.

[0105] If the number of frames in the confirmation frame of the target receiving device remains unchanged, the current number of frames sent by each sending device remains unchanged, and the process returns to the step of adjusting the number of frames sent by each sending device according to the number of frames in the confirmation frame of the target receiving device.

[0106] If the number of frames in the confirmation frame of the target receiving device decreases, the number of sending frames of each sending device is reduced according to the second preset value, and the step of adjusting the number of sending frames of each sending device according to the number of frames in the confirmation frame of the target receiving device is returned.

[0107] Figure 4 The following is a flowchart of the implementation of the sending device adjusting the number of sent frames provided by the embodiment of the present invention; Figure 4 This embodiment is described. Figure 4 Where k represents the number of frames sent by each sending device.

[0108] In this embodiment, the second preset value may be the minimum amount by which each sending device can adjust the number of frames to be sent each time. Of course, it may also be set as required in actual applications.

[0109] In this embodiment, when the number of frames in the confirmation frame of the target receiving device increases, it means that the current network pressure has not reached the limit and the transmission speed can still be increased. Therefore, each sending device can increase its own number of sending frames according to the second preset value, and transmit data to the target receiving device according to the increased number of sending frames, so that the target receiving device recalculates the current network pressure to adjust the number of receiving frames at the next moment. Accordingly, each sending device adjusts its own number of sending frames at the next moment according to the number of frames in the confirmation frame of the target receiving device at the next moment until the file transfer is completed.

[0110] Accordingly, when the number of received frames of the target receiving device remains unchanged, it means that the transmission using the current number of sent frames and received frames is the fastest transmission speed within the maximum pressure range. Therefore, there is no need to adjust the number of sent frames itself.

[0111] When the number of received frames of the target receiving device decreases, it means that the network pressure at this time exceeds the maximum network pressure that the target receiving device can withstand. Continuing to transmit with the current number of sent frames will cause network collapse or frame loss. Therefore, it is necessary to reduce the number of sent frames accordingly.

[0112] According to these three situations, the number of frames sent by the sender is adjusted and sent until the file transfer is completed.

[0113] In addition, it should be understood that the method provided in Example 3 is the same as the method provided in Example 1, both of which are used to transmit I frames in the standard IEC104 protocol.

[0114] In an optional embodiment, if the current network pressure is equal to the network pressure threshold of the target receiving device, the method further includes:

[0115] Receives the number of sending devices connected to the target receiving device that sent the message.

[0116] If the number of sending devices connected to the target receiving device at the current moment increases, the number of sending frames of the sending devices connected to the target receiving device at the previous moment is reduced according to the third preset value to obtain the number of sending frames of each sending device at the next moment.

[0117] If the number of sending devices connected to the target receiving device at the current moment remains unchanged, the number of sending frames of the sending devices connected to the target receiving device remains unchanged.

[0118] If the number of sending devices connected to the target receiving device at the current moment decreases, the number of sending frames of the sending devices connected to the target receiving device at the previous moment is increased according to the third preset value to obtain the number of sending frames of each sending device at the next moment.

[0119] In this embodiment, different from the adjustment process in step 220, this embodiment belongs to a special case where the current network pressure is equal to the network pressure threshold of the target receiving device. In this case, the number of frames sent by each sending device can be adjusted by the method in step 220, or by the following method:

[0120] In this embodiment, when the current network pressure is equal to the network pressure threshold of the target receiving device, then:

[0121] u(t)=Δk1+Δk2+…+Δk n

[0122] Δk n =k n (t2)-k n (t1)

[0123] Where n represents the nth sending device connected to the target receiving device; Δk n It represents the change in the number of I-frame format frames sent from the n-th sending device and not confirmed by the target receiving device at the current moment; kn(t2) and kn(t1) represent the number of I-frame format frames sent from the n-th sending device and not confirmed by the target receiving device at time t2 and time t1 respectively; wherein, time t2 is the current moment and time t1 is the previous moment.

[0124] In this embodiment, the target receiving device can also determine the number of sending devices connected to itself, and send the determined number of sending devices to each sending device.

[0125] When the current network pressure is equal to the network pressure threshold of the target receiving device, if the number of sending devices connected to the target receiving device at the current moment increases, it means that the sending device connected to the target receiving device at the previous moment has not completed the data transmission, and a new sending device has been added for data transmission. If this state is maintained, the network pressure at the next moment is likely to be greater than the network pressure threshold of the target receiving device.

[0126] To avoid this situation, it is necessary to reduce the number of sending frames of the sending device connected to the target receiving device at the previous moment according to the third preset value, and use the reduced number of sending frames of each sending device as the number of sending frames of each sending device at the next moment.

[0127] Here, for the sake of convenience of explanation, the previous moment may be defined as the first moment, the current moment may be defined as the second moment, and the next moment may be defined as the third moment.

[0128] At the next moment, that is, the third moment, if the current network pressure is not greater than the network pressure threshold of the target receiving device, in order to ensure the transmission balance of each sending device, the number of sending frames of each sending device at the first moment can be reduced according to the third preset value. At the same time, the number of sending frames of the newly added sending device at the first moment can be increased according to the third preset value until the number of sending frames of each sending device is the same, or the data transmission is completed.

[0129] In this embodiment, if the number of sending devices connected to the target receiving device at the current moment remains unchanged, the number of sending frames of the sending device connected to the target receiving device remains unchanged.

[0130] In this embodiment, if the number of sending devices connected to the target receiving device at the current moment decreases, it means that a sending device has completed the data it is responsible for transmitting. In order to speed up the transmission speed, the number of sending frames of the remaining sending devices can be increased according to the third preset value to obtain the number of sending frames of each sending device at the next moment.

[0131] In this embodiment, the third preset value may be equal to the second preset value, that is, it may be the minimum amount by which each sending device can adjust the number of sent frames each time. Of course, it may also be set as needed in actual applications.

[0132] In summary, similar to Example 1, the method provided in Example 3 is applied to a sending device connected to a target receiving device, which can improve the transmission speed of information frames. Below, in Example 4, a method is provided that is applied to a sending device connected to a target receiving device and can improve the transmission speed of message frames.

[0133] Example 4:

[0134] In an optional embodiment, each sending device uses the extended IEC104 protocol to send files.

[0135] Accordingly, the extended IEC104 protocol is obtained by increasing the length of each frame of the IEC104 message in the standard IEC104 protocol.

[0136] Each sending device transmits each IEC104 message frame according to the preset byte length through the extended IEC104 protocol.

[0137] This embodiment is the same as Example 2, so you can refer to the relevant content in Example 2 and will not repeat it here.

[0138] Based on the methods provided in Example 2 and Example 3, a specific example is used for verification below.

[0139] The standard IEC104 protocol is used for file transmission, with 230 bytes of file data per frame, and the receiving device transmits at least 12 bytes per frame. Therefore, the protocol characteristic values ​​can be expressed as: k = 12, w = 8;

[0140] It takes 4560 frames to transfer a 1Mb file. The calculation steps are:

[0141] 1Mb-230byte=1024*1024 / 230

[0142] The sending device sends a frame every 10ms, and the receiving device processes a frame every 10ms. If the transmission time of each frame is not taken into account, at the 90th ms, the receiving device has processed the 8th frame, and the sending device has sent the 9th frame. However, at this time, the receiving device needs to send a confirmation frame, which will take 10ms longer. In this case, the total transmission time required to transmit a 1Mb file is:

[0143] 45600ms+570ms=46.170S (1 frame is transmitted every 10ms)

[0144] This embodiment adopts the extended IEC104 protocol for transmission, and each frame of 1450 bytes of file data uses the protocol characteristic values: k=12, w=8;

[0145] It takes 724 frames to transfer a 1Mb file, and the total transmission time required to transfer a 1Mb file is:

[0146] 7240ms+905ms=8.145S, compared with the traditional method, the efficiency is improved by 5.67 times

[0147] The extended protocol is used for transmission, with 1450 bytes of file data per frame. Under ideal conditions, when the receiving device can stably process the maximum number of network frames at the same time (network pressure will not cause frame loss, and the transmission efficiency is the highest), the characteristic value can be set to the maximum value. At this time, if k=42 and w=38, 724 frames are required to transmit a 1Mb file (changing the k and w values ​​does not affect the number of frames, but reduces the frequency of sending confirmation frames), and the transmission time is: 7240ms+191ms=7.431S. At this time, the efficiency is improved by 6.21 times.

[0148] It can be seen that based on the above examples, the methods provided in Example 2 and Example 3 can significantly improve the file transfer speed.

[0149] Example 5:

[0150] Figure 5is a system architecture diagram of a data transmission system between multiple devices in a distribution network system provided by an embodiment of the present invention, such as Figure 5 As shown, the system may include:

[0151] At least one target receiving device, and at least two sending devices connected to the at least one target receiving device.

[0152] Among them, at least one target receiving device is used to implement the method provided in either Example 1 or Example 2.

[0153] The sending device is used to implement the method provided in any one of Example 3 or Example 4.

[0154] In this embodiment, the data transmission system between multiple devices in the distribution network system may include multiple target receiving devices and multiple sending devices. Taking any target receiving device as a reference, the target receiving device and all sending devices connected to the target receiving device are taken as a group. For the target receiving device in the group, the method provided in Example 1 or Example 2 can be used for data transmission; for each receiving device in the group, the method provided in Example 3 or Example 4 can be used for data transmission. The specific transmission method can refer to the other related embodiments mentioned above, which will not be repeated here.

[0155] It should be understood that the order of execution of the steps in the above embodiment does not necessarily mean 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 the embodiment of the present invention.

[0156] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0157] Those skilled in the art will appreciate that the units and algorithm steps of each example 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 performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0158] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A data transmission method between multiple devices in a distribution network system, characterized in that: A target receiving device applied to a target distribution network system; the method comprises: Receive the number of transmission frames of each transmission device connected to the target receiving device; Determine the current network pressure of the target receiving device according to the number of frames sent by each sending device; According to the current network pressure, the number of received frames of the target receiving device is adjusted, and a confirmation frame is replied to each sending device, so that each sending device adjusts its own number of sent frames based on the number of frames in the confirmation frame.

2. The data transmission method between multiple devices in a distribution network system according to claim 1, characterized in that: The step of adjusting the number of frames received by the target receiving device according to the current network pressure includes: If the current network pressure is greater than the network pressure threshold of the target receiving device, the number of received frames of the target receiving device is reduced according to the first preset value, and the step of determining the current network pressure of the target receiving device according to the number of sent frames of each sending device is returned; If the current network pressure is equal to the network pressure threshold of the target receiving device, the current number of received frames of the target receiving device is kept unchanged, and the step of determining the current network pressure of the target receiving device according to the number of sent frames of each sending device is returned; If the current network pressure is less than the network pressure threshold of the target receiving device, the number of received frames of the target receiving device is increased according to the first preset value, and the step of determining the current network pressure of the target receiving device according to the number of sent frames of each sending device is returned to.

3. The data transmission method between multiple devices in a distribution network system according to claim 1, characterized in that: The target receiving device adopts the extended IEC104 protocol to receive files.

4. The data transmission method between multiple devices in a distribution network system according to claim 3, characterized in that: The extended IEC104 protocol is obtained by increasing the length of each frame of IEC104 message in the standard IEC104 protocol; The target receiving device receives each IEC104 message frame according to the preset byte length through the extended IEC104 protocol.

5. The data transmission method between multiple devices in a distribution network system according to claim 1, characterized in that: The determining, according to the number of frames sent by each sending device, the current network pressure of the target receiving device includes: For any sending device, according to the current number of received frames of the target receiving device, the current characteristic value of the sending device is calculated; according to the current characteristic value, the current network pressure of the sending device is calculated; The sum of the current network pressures corresponding to the sending devices connected to the target receiving device is used as the current network pressure of the target receiving device.

6. A data transmission method between multiple devices in a distribution network system, characterized in that: Applicable to any sending device connected to the target distribution network system according to any one of claims 1 to 5; the method comprises: Receiving a confirmation frame replied by the target receiving device; According to the number of frames in the confirmation frame of the target receiving device, the number of sending frames of each sending device is adjusted, and the adjusted number of sending frames is sent to the target receiving device.

7. The data transmission method between multiple devices in a distribution network system according to claim 6, characterized in that: The step of adjusting the number of frames sent by the sending device according to the number of frames in the confirmation frame of the target receiving device comprises: If the number of frames in the confirmation frame of the target receiving device increases, the number of frames sent by each sending device is increased according to the second preset value, and the step of adjusting the number of frames sent by each sending device according to the number of frames in the confirmation frame of the target receiving device is returned; If the number of frames in the confirmation frame of the target receiving device remains unchanged, the current number of frames sent by each sending device remains unchanged, and the process returns to the step of adjusting the number of frames sent by each sending device according to the number of frames in the confirmation frame of the target receiving device; If the number of frames in the confirmation frame of the target receiving device decreases, the number of sending frames of each sending device is reduced according to the second preset value, and the step of adjusting the number of sending frames of each sending device according to the number of frames in the confirmation frame of the target receiving device is returned.

8. The data transmission method between multiple devices in a distribution network system according to claim 6, characterized in that: If the current network pressure is equal to the network pressure threshold of the target receiving device, the method further includes: receiving the number of sending devices connected to the target receiving device sent by the target receiving device; If the number of sending devices connected to the target receiving device at the current moment increases, the number of sending frames of the sending devices connected to the target receiving device at the previous moment is reduced according to the third preset value to obtain the number of sending frames of each sending device at the next moment; If the number of sending devices connected to the target receiving device at the current moment remains unchanged, the number of sending frames of the sending device connected to the target receiving device remains unchanged; If the number of sending devices connected to the target receiving device at the current moment decreases, the number of sending frames of the sending devices connected to the target receiving device at the previous moment is increased according to the third preset value to obtain the number of sending frames of each sending device at the next moment.

9. The data transmission method between multiple devices in a distribution network system according to claim 6, characterized in that: The method further comprises: Each sending device uses the extended IEC104 protocol to send files; The extended IEC104 protocol is obtained by increasing the length of each frame of IEC104 message in the standard IEC104 protocol; Each sending device transmits each IEC104 message frame according to the preset byte length through the extended IEC104 protocol.

10. A data transmission system between multiple devices in a distribution network system, characterized in that: comprising at least one target receiving device, and at least two sending devices connected to the at least one target receiving device; Wherein, the at least one target receiving device is used to implement the method according to any one of claims 1 to 5; The sending device is used to implement the method according to any one of claims 6 to 9.

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