Power time sensitive data flow scheduling method and system based on TSN

Abstract

The invention discloses a TSN-based power time-sensitive data stream scheduling method and system, and the method comprises the steps: firstly calculating a periodic time-sensitive data stream set needing to be borne on each transmission link; if the sum of the number of time slots occupied when each periodic time-sensitive data stream is transmitted on the transmission link is not greater than the number of time slots contained in a scheduling period, calculating a time slot scheduling priority coefficient of each periodic time-sensitive data stream, and starting from the last time slot of the scheduling period according to an ascending order of the priority coefficients, scheduling the time slots in the scheduling period; and allocating time slot serial numbers to all the periodic time-sensitive data streams on the current transmission link, otherwise, changing the periodic time-sensitive data stream with the maximum transmission link conflict factor to be transmitted at other ports of the TSN switch, and performing time slot allocation again. According to the method, the periodic transmission requirement of the periodic time-sensitive data stream set is met, and the deterministic transmission delay is ensured.

Description

Technical Field

[0001] The present invention relates to the field of power system communication technology, and in particular to a method and system for scheduling power time-sensitive data streams based on TSN. Background Art

[0002] The SV (Sampling Value) connected to the relay protection equipment of the smart substation is a series of discrete and digital current and voltage phasor sampling values. The sampling synchronization of different intervals and different sampling points in the same interval means obtaining the phasor values ​​occurring at the same time through discrete values ​​serial in time. The core issue of achieving sampling synchronization is to accurately know the transmission delay of multiple SV message data, deduce the occurrence time of SV message transmission based on this, and finally achieve synchronization of multiple SVs through interpolation operations.

[0003] Generic Object Oriented Substation Event (GOOSE) messages are mainly used to transmit data with real-time requirements such as protection tripping, circuit breaker position, and measurement and control interlocking in substations. When an event occurs in the device (such as switch status change), the data in the GOOSE data set changes, and the device immediately sends all the data in the data set. Therefore, GOOSE messages have the characteristics of burstiness and time sensitivity.

[0004] Substation burst traffic transmission is often difficult because of the lack of reasonable planning of transmission paths, resulting in large transmission delays. In the scenario of intelligent substation switch action event collection and analysis, fault analysis and disposal will be affected, reducing the reliability of power supply. Existing intelligent substation SV and GOOSE messages face time slot scheduling problems and low-latency fast forwarding path selection problems when transmitting in multiple cycles. Summary of the invention

[0005] Purpose of the invention: The purpose of the present invention is to provide a method and system for scheduling power time-sensitive data streams based on TSN, which can complete the time slot scheduling of all periodic time-sensitive data streams and meet the transmission requirements of bursty time-sensitive data streams.

[0006] Technical solution: The TSN-based power time-sensitive data flow scheduling method of the present invention comprises the following steps:

[0007] (1) For all transmission links in the local communication network topology of the smart substation, calculate the set of periodic time-sensitive data flows that need to be carried on the transmission link;

[0008] (2) A transmission link e i There are two or more periodic time-sensitive data flows f nDuring transmission, the transmission link collision factor of each periodic time-sensitive data flow is calculated The number of conflicting data flows; e i ∈E,1≤i≤E,f n ,1≤n≤N, E is the number of transmission links, N is the number of periodic time-sensitive data flows;

[0009] (3) If each periodic time-sensitive data flow f on the transmission link n The sum of the number of time slots occupied during transmission is not greater than the number of time slots contained in a scheduling cycle, then calculate each periodic time-sensitive data flow f n The time slot scheduling priority coefficient is , and step (4) is executed; otherwise, step (5) is executed;

[0010] (4) According to the ascending order of priority coefficient, starting from the last time slot of the scheduling period, the current transmission link e i All periodic time-sensitive data flows f n Assigning time slot numbers; returning to step (2) until the time slot allocation of periodic time-sensitive data streams of all transmission links is completed;

[0011] (5) Change the periodic time-sensitive data flow with the largest transmission link conflict factor to be transmitted on other ports of the TSN switch, and return to step (2).

[0012] Furthermore, in step (4), after allocating time slots for periodic time-sensitive data streams of all transmission links, a shortest path search algorithm is used to find a transmission path with the shortest transmission delay for bursty time-sensitive data streams.

[0013] Furthermore, the transmission link conflict factor in step (2) is The initial value is 0.

[0014] Furthermore, the time slot scheduling priority coefficient in step (3) is in They are periodic time-sensitive data flows f n In the transmission link i The set of all previous transmission links and the starting sequence number of the allocated transmission time slots.

[0015] Furthermore, in step (3), all periodic time-sensitive data streams have a transmission period T n , the lowest common multiple of 1≤n≤N is the scheduling period T Schedu , the single-node transmission delay TS of all periodic time-sensitive data flows n , the greatest common divisor of 1≤n≤N is the scheduling time slot length T S ; The number of time slots occupied by each periodic time-sensitive data stream transmission is is the round-up operator. The number of time slots in a scheduling cycle is Slot TSch =T Schedu / T S .

[0016] The TSN-based power time-sensitive data flow scheduling system of the present invention includes:

[0017] A periodic time-sensitive data flow set calculation unit, used for calculating the periodic time-sensitive data flow set to be carried on all transmission links in the local communication network topology of the smart substation;

[0018] The transmission link conflict factor calculation unit is used to calculate the transmission link conflict factor in a transmission link. i There are two or more periodic time-sensitive data flows f n During transmission, the transmission link collision factor of each periodic time-sensitive data flow is calculated The number of conflicting data flows; e i ∈E,1≤i≤E,f n ,1≤n≤N, E is the number of transmission links, N is the number of periodic time-sensitive data flows;

[0019] Periodic time-sensitive data flow time slot allocation unit, if each periodic time-sensitive data flow f on the transmission link n The sum of the number of time slots occupied during transmission is not greater than the number of time slots contained in a scheduling cycle, then calculate each periodic time-sensitive data flow f n The time slot scheduling priority coefficient of the current transmission link e is calculated according to the ascending order of the priority coefficient, starting from the last time slot of the scheduling period. i All periodic time-sensitive data flows f n Assign time slot numbers; return to step (2) until all periodic time-sensitive data stream time slots for all transmission links are assigned; if each periodic time-sensitive data stream f on the transmission link n If the sum of the number of time slots occupied during transmission is less than the number of time slots included in a scheduling cycle, the periodic time-sensitive data flow with the largest transmission link conflict factor is changed to be transmitted on other ports of the TSN switch, and the periodic time-sensitive data flow time slot allocation unit is returned.

[0020] Furthermore, it also includes a burst time-sensitive data flow path allocation unit, which is used to find the transmission path with the minimum transmission delay of the burst time-sensitive data flow through the shortest path search algorithm after completing the periodic time-sensitive data flow time slot allocation of all transmission links.

[0021] Furthermore, in the transmission link conflict factor calculation unit, the transmission link conflict factor The initial value is 0.

[0022] Furthermore, in the periodic time-sensitive data stream time slot allocation unit, the time slot scheduling priority coefficient is in They are periodic time-sensitive data flows f n In the transmission link i The set of all previous transmission links and the starting sequence number of the allocated transmission time slots.

[0023] Furthermore, in the periodic time-sensitive data stream time slot allocation unit, all periodic time-sensitive data stream transmission periods T n , the lowest common multiple of 1≤n≤N is the scheduling period T Schedu , the single-node transmission delay TS of all periodic time-sensitive data flows n , the greatest common divisor of 1≤n≤N is the scheduling time slot length T S ; The number of time slots occupied by each periodic time-sensitive data stream transmission is is the round-up operator. The number of time slots in a scheduling cycle is Slot TSch =T Schedu / T S .

[0024] The electronic device described in the present invention includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the computer program is loaded into the processor, the TSN-based power time-sensitive data flow scheduling method is implemented.

[0025] The computer-readable storage medium of the present invention stores a computer program, and when the computer program is executed by a processor, the TSN-based power time-sensitive data flow scheduling method is implemented.

[0026] Beneficial effects: Compared with the prior art, the advantages of the present invention are: (1) Under the condition of known transmission paths of multiple periodic time-sensitive data streams, the present invention reasonably determines the scheduling period and transmission time slot, and allocates the transmission time slot of each path on the transmission path to each periodic time-sensitive data stream through the time slot scheduling algorithm, so as to meet its periodic transmission requirements and ensure deterministic transmission delay. (2) The method disclosed in the present invention can ensure the minimum delay transmission requirements of bursty time-sensitive data streams, and effectively improve the timeliness of analysis and handling of power grid equipment action events. (3) The TSN network periodic and bursty traffic scheduling problem involved in the present invention belongs to the category of combinatorial optimization, and it is often very difficult to solve the optimal solution. The present invention discloses a heuristic algorithm with low algorithm complexity and higher practical application promotion value. (4) The present invention can also select the transmission path with the lowest delay for bursty time-sensitive data streams while meeting the transmission requirements of periodic time-sensitive data streams, fully meeting the requirements of synchronous sampling and rapid event uploading of intelligent substation measurement, control and protection devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a flow chart of the method for scheduling power time-sensitive data streams of the present invention;

[0028] Figure 2 This is a topological diagram of the local communication network of the smart substation according to an embodiment of the present invention. DETAILED DESCRIPTION

[0029] The technical solution of the present invention is further described below in conjunction with the accompanying drawings.

[0030] like Figure 1 As shown, the TSN-based power time-sensitive data flow scheduling method includes the following steps.

[0031] like Figure 2 As shown, the local communication network topology of the smart substation in this embodiment is TP(V,E); where E is the set of all transmission links; V = {V S ,V D} is the set of all data transmission source nodes and destination nodes, V S 、V D They are source nodes and destination node sets respectively, and the source node set is the protection and measurement and control device in the access layer of the network topology, and the destination node set is the relevant analysis and control system of the station control layer of the measurement and control, protection device SV message and GOOSE message transmission destination node; v s ∈V S ,v d ∈V Dare the source node and the destination node respectively, and s=1,2,...,S,d=1,2,...,D are the index variables of the source node and the destination node respectively, and S,D are the number of source nodes and the destination node respectively; the middle switching layer of the network topology contains multiple TSN switches, and the set SW SW ={sw 1 ,sw 2 ,...,sw SW} represents the TSN switch set, and i = 1, 2, ..., SW is the switch set index variable, SW is the number of TSN switches; there are N periodic time-sensitive data flows that need to be transmitted in the network topology, and each periodic time-sensitive data flow is represented by f n ,n=1,2,...,N, n is the periodic time-sensitive data stream index variable, and the transmission period is T n , the transmission delay required for each node on the transmission path is TS n , and the data stream transmission path is h n is the data stream f n The number of intermediate TSN switches that the data flow passes through. n +1 hop forwarding from source node v s Arrival at destination node v d , is a periodic time-sensitive data stream f n All the links passed.

[0032] T n , the lowest common multiple of 1≤n≤N (in milliseconds) is the scheduling period T Schedu (in milliseconds), the single-node transmission delay TS of all periodic time-sensitive data flows n , the greatest common divisor of 1≤n≤N (in milliseconds) is the scheduling time slot length T S Therefore, each periodic time-sensitive data stream occupies a time slot number of Slot n =TS n / T S , the number of time slots in a scheduling cycle is Slot TSch =T Schedu / T S .

[0033] The TSN network of the smart substation adopts full-duplex communication, so only the single-direction transmission time slot scheduling method of N-channel periodic time-sensitive data streams needs to be considered, and it is applicable to both uplink and downlink links and does not affect each other. The following time slot scheduling method is called to reasonably allocate time slots that meet the transmission cycle characteristics for each data stream on each transmission link, and at the same time allocate the minimum delay transmission path for bursty time-sensitive data streams.

[0034] The specific steps are as follows:

[0035] Step 1: i = 1, 2, ..., E, where E is the transmission link index variable and the number of links respectively. For all transmission links e in the network topology, i ∈E,1≤i≤E, calculate the set of periodic time-sensitive data flows that need to be carried on the link Ω i ,f n ∈Ω i ,if e i ∈PL fn ,1≤n≤N. Define variables is a periodic time-sensitive data stream f n ,1≤n≤N transmission link conflict factor, the initial value is 0; that is, in a certain transmission link e i ∈E,1≤i≤E, when there are more than two data streams, calculate each data stream f n Conflict Factor The number of conflicting data flows.

[0036]

[0037] Step 2a for link e i ,calculate like Calculate the transmission link e i The time slot scheduling priority coefficients of all periodic time-sensitive data flows in They are periodic time-sensitive data flows f n In the transmission link i The starting sequence number of all previously allocated transmission time slots. Skip to step 2c.

[0038] Step 2b assigns starting time slot numbers to all periodic time-sensitive data streams on the current transmission link in ascending order of priority coefficient, starting from the last time slot of the scheduling cycle, from back to front, to ensure that the periodic time-sensitive data stream with the lowest priority is scheduled at the very end of the scheduling cycle of this transmission link, updates i=i+1, and returns to step 2a to continue executing until all transmission links in the network topology have completed time slot allocation.

[0039] Step 2c: Select Cof nThe largest periodic time-sensitive data flow is removed from the current set of data flows to be scheduled and is transmitted on other ports of the TSN switch, thereby reducing the probability of conflict for all periodic time-sensitive data flows. Update the conflict factor Cof of the remaining periodic time-sensitive data flows according to the method described in step 1. n , return to step 2a and start again from the current transmission link e i Continue execution.

[0040] Step 3: Update TP(V, E) to TP according to the time slot allocation result after steps 1 to 2 are completed. update (V,E),TP update In (V, E), the transmission links whose remaining transmission time slots cannot meet the transmission requirements of the burst time-sensitive data stream are deleted. According to the time slot scheduling method described in step 1-step 2, the initial transmission time slot can be reserved for the burst time-sensitive data stream. Therefore, only the shortest path search algorithm, such as Dijkstra algorithm, is needed to find the path with the minimum transmission delay for the burst time-sensitive data stream.

[0041] The TSN-based power time-sensitive data flow scheduling system of the present invention includes:

[0042] The periodic time-sensitive data flow set calculation unit is used to calculate the periodic time-sensitive data flow set to be carried on all transmission links in the local communication network topology of the smart substation.

[0043] The transmission link conflict factor calculation unit is used to calculate the transmission link conflict factor in a transmission link. i There are two or more periodic time-sensitive data flows f n During transmission, the transmission link collision factor of each periodic time-sensitive data flow is calculated The number of conflicting data flows; e i ∈E,1≤i≤E,f n ,1≤n≤N, E is the number of transmission links, and N is the number of periodic time-sensitive data flows.

[0044] Periodic time-sensitive data flow time slot allocation unit, if each periodic time-sensitive data flow f on the transmission link n The sum of the number of time slots occupied during transmission is not greater than the number of time slots contained in a scheduling cycle, then calculate each periodic time-sensitive data flow f n The time slot scheduling priority coefficient of the current transmission link e is calculated according to the ascending order of the priority coefficient, starting from the last time slot of the scheduling period. i All periodic time-sensitive data flows f nAssign time slot numbers; return to step (2) until all periodic time-sensitive data stream time slots for all transmission links are assigned; if each periodic time-sensitive data stream f on the transmission link n If the sum of the number of time slots occupied during transmission is less than the number of time slots included in a scheduling cycle, the periodic time-sensitive data flow with the largest transmission link conflict factor is changed to be transmitted on other ports of the TSN switch, and the periodic time-sensitive data flow time slot allocation unit is returned.

[0045] The burst time-sensitive data flow path allocation unit is used to find the transmission path with the minimum transmission delay of the burst time-sensitive data flow through the shortest path search algorithm after completing the periodic time-sensitive data flow time slot allocation of all transmission links.

[0046] The electronic device described in the present invention includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the computer program is loaded into the processor, the TSN-based power time-sensitive data flow scheduling method is implemented.

[0047] The computer-readable storage medium of the present invention stores a computer program, and when the computer program is executed by a processor, the TSN-based power time-sensitive data flow scheduling method is implemented.

[0048] The computer-readable storage media may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, flash memory, or any other medium that can be used to store the desired program code in the form of instructions or data structures and that can be accessed by a computer.

[0049] The processor is used to execute the computer program stored in the memory to implement each step of the method involved in the above embodiment.

Claims

1. A method for scheduling power time-sensitive data streams based on TSN, characterized in that: The steps include: (1) For all transmission links in the local communication network topology of the smart substation, calculate the set of periodic time-sensitive data flows that need to be carried on the transmission link; (2) A transmission link e i There are two or more periodic time-sensitive data flows f n During transmission, the transmission link collision factor of each periodic time-sensitive data flow is calculated Number of data streams; e i ∈E,1≤i≤E,f n ,1≤n≤N, E is the number of transmission links, N is the number of periodic time-sensitive data flows; (3) If each periodic time-sensitive data flow f on the transmission link n The sum of the number of time slots occupied during transmission is not greater than the number of time slots contained in a scheduling cycle, then calculate each periodic time-sensitive data flow f n The time slot scheduling priority coefficient is , and step (4) is executed; otherwise, step (5) is executed; (4) According to the ascending order of priority coefficient, starting from the last time slot of the scheduling period, the current transmission link e i All periodic time-sensitive data flows f n Assign time slot numbers; Return to step (2) until the periodic time-sensitive data flow time slot allocation of all transmission links is completed; (5) Change the periodic time-sensitive data flow with the largest transmission link conflict factor to be transmitted on other ports of the TSN switch, and return to step (2).

2. The method for scheduling power time-sensitive data streams based on TSN according to claim 1, characterized in that: In step (4), after allocating time slots for periodic time-sensitive data streams on all transmission links, a shortest path search algorithm is used to find a transmission path with the shortest transmission delay for bursty time-sensitive data streams.

3. The method for scheduling power time-sensitive data streams based on TSN according to claim 1, characterized in that: The transmission link conflict factor in step (2) The initial value is 0.

4. The method for scheduling power time-sensitive data streams based on TSN according to claim 1, characterized in that: The time slot scheduling priority coefficient in step (3) is in They are periodic time-sensitive data flows f n In the transmission link i The set of all previous transmission links and the starting sequence number of the allocated transmission time slots.

5. The method for scheduling power time-sensitive data streams based on TSN according to claim 1, characterized in that: In step (3), all periodic time-sensitive data streams have a transmission period T n , the lowest common multiple of 1≤n≤N is the scheduling period T Schedu , the single-node transmission delay TS of all periodic time-sensitive data flows n , the greatest common divisor of 1≤n≤N is the scheduling time slot length T S ; The number of time slots occupied by each periodic time-sensitive data stream transmission is is the round-up operator. The number of time slots in a scheduling cycle is Slot TSch =T Schedu / T S .

6. A TSN-based power time-sensitive data flow scheduling system, characterized in that: include: A periodic time-sensitive data flow set calculation unit, used for calculating the periodic time-sensitive data flow set to be carried on all transmission links in the local communication network topology of the smart substation; The transmission link conflict factor calculation unit is used to calculate the transmission link conflict factor in a transmission link. i There are two or more periodic time-sensitive data flows f n During transmission, the transmission link collision factor of each periodic time-sensitive data flow is calculated Number of data streams; e i ∈E,1≤i≤E,f n ,1≤n≤N, E is the number of transmission links, N is the number of periodic time-sensitive data flows; Periodic time-sensitive data flow time slot allocation unit, if each periodic time-sensitive data flow f on the transmission link n The sum of the number of time slots occupied during transmission is not greater than the number of time slots contained in a scheduling cycle, then calculate each periodic time-sensitive data flow f n The time slot scheduling priority coefficient of the current transmission link e is calculated according to the ascending order of the priority coefficient, starting from the last time slot of the scheduling period. i All periodic time-sensitive data flows f n Assign time slot numbers; Return to step (2) until the time slot allocation of periodic time-sensitive data flows on all transmission links is completed; if each periodic time-sensitive data flow f on the transmission link n If the sum of the number of time slots occupied during transmission is less than the number of time slots included in a scheduling cycle, the periodic time-sensitive data flow with the largest transmission link conflict factor is changed to be transmitted on other ports of the TSN switch, and the periodic time-sensitive data flow time slot allocation unit is returned.

7. The TSN-based power time-sensitive data flow scheduling system according to claim 6, characterized in that: It also includes a burst time-sensitive data flow path allocation unit, which is used to find the transmission path with the minimum transmission delay of the burst time-sensitive data flow through the shortest path search algorithm after completing the periodic time-sensitive data flow time slot allocation of all transmission links.

8. The TSN-based power time-sensitive data flow scheduling system according to claim 6, characterized in that: In the transmission link conflict factor calculation unit, the transmission link conflict factor The initial value is 0.

9. The TSN-based power time-sensitive data flow scheduling system according to claim 6, characterized in that: In the periodic time-sensitive data stream time slot allocation unit, the time slot scheduling priority coefficient is in They are periodic time-sensitive data flows f n In the transmission link i The set of all previous transmission links and the starting sequence number of the allocated transmission time slots.

10. The TSN-based power time-sensitive data flow scheduling system according to claim 6, characterized in that: In the periodic time-sensitive data stream time slot allocation unit, all periodic time-sensitive data stream transmission periods T n , the lowest common multiple of 1≤n≤N is the scheduling period T Schedu , the single-node transmission delay TS of all periodic time-sensitive data flows n , the greatest common divisor of 1≤n≤N is the scheduling time slot length T S ; The number of time slots occupied by each periodic time-sensitive data stream transmission is is the round-up operator. The number of time slots in a scheduling cycle is Slot TSch =T Schedu / T S .

11. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the computer program is loaded into a processor, the TSN-based power time-sensitive data flow scheduling method according to any one of claims 1 to 5 is implemented.

12. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the TSN-based power time-sensitive data flow scheduling method according to any one of claims 1 to 5 is implemented.

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