阅读说明：本技术 一种电力通信继电保护业务时延控制方法、系统及继电保护设备 (Power communication relay protection service time delay control method and system and relay protection equipment ) 是由 李伟 戴勇 汪大洋 江凇 沈盟 魏英达 徐勇 贾平 李沛 吴细老 蒋春霞 柳旭 于 2021-09-14 设计创作，主要内容包括：本发明公开了电力通信继电保护业务时延控制方法、系统及继电保护设备,各继电保护设备通过多个FlexE交换机构成的FlexE切片网络连接形成传输环网,对传输环网中的各继电保护设备和FlexE交换机进行时钟同步；继电保护设备接收对端继电保护设备经FlexE切片网络发送的采样数据报文,解析获得采样数值和延迟累计,延迟累计的时间值是传输路径上相邻通信双方的帧时间戳之差的累计,作为对端到该继电保护设备的总路径时延；继电保护设备根据总路径时延获得与对端同步采集的采样数值。本发明测量两个继电保护设备之间的FlexE切片网络的总路径时延,据此对采样时间进行调整,保证两个继电保护设备的同步测量。(The invention discloses a time delay control method, a time delay control system and relay protection equipment for relay protection service of power communication, wherein each relay protection equipment is connected through a Flexe slice network formed by a plurality of Flexe switches to form a transmission ring network, and clock synchronization is carried out on each relay protection equipment and the Flexe switches in the transmission ring network; the relay protection equipment receives a sampled data message sent by the relay protection equipment at the opposite terminal through a Flexe slice network, and analyzes the sampled data message to obtain a sampled value and a delay accumulation, wherein the delay accumulation time value is the accumulation of the difference between frame timestamps of two adjacent communication parties on a transmission path and is used as the total path time delay from the opposite terminal to the relay protection equipment; and the relay protection equipment obtains a sampling value synchronously acquired with the opposite terminal according to the total path time delay. The invention measures the total path time delay of the Flexe slice network between two relay protection devices, adjusts the sampling time according to the total path time delay, and ensures the synchronous measurement of the two relay protection devices.)

1. A time delay control method for a power communication relay protection service is characterized in that each relay protection device is connected through a Flexe slice network formed by a plurality of Flexe switches to form a transmission ring network, and the time delay control method when the relay protection device executes the relay protection service comprises the following processes:

clock synchronization is carried out on each relay protection device and a Flexe switch in the transmission ring network;

the method comprises the steps that a relay protection device receives a sampling data message sent by an opposite terminal relay protection device through a Flexe slice network, wherein the sampling data message comprises a sampling numerical value, a frame timestamp and a delay accumulation;

the relay protection equipment analyzes the sampled data message to obtain a sampling value and a delay accumulation, wherein the time value of the delay accumulation is the accumulation of the difference of frame timestamps of two adjacent communication parties on a transmission path and is used as the total path time delay from the opposite end to the relay protection equipment;

and the relay protection equipment obtains a sampling value synchronously acquired with the opposite terminal according to the total path time delay.

2. The delay control method for the relay protection service in power communication according to claim 1, further comprising:

the relay protection equipment judges whether the power grid transmission line has a fault according to the consistency of the sampling values of the relay protection equipment and the opposite terminal, and triggers corresponding protection actions if the fault is judged.

3. The method according to claim 1, wherein the clock synchronization of each relay protection device and a FlexE switch in the transmission ring network comprises:

and performing clock synchronization on each relay protection device and the Flexe switch in the transmission ring network through a 1588 clock source.

4. The method for controlling delay of relay protection service in power communication according to claim 3, wherein the step of performing clock synchronization on each relay protection device and the FlexE switch in the transmission ring network through the 1588 clock source comprises:

each Flexe switch of each relay protection device receives a clock synchronization signal sent by a 1588 clock source respectively to obtain synchronization signal sending time t₁And a synchronization signal reception time t₂；

Each relay protection device and the Flexe exchanger respectively send clock synchronization response signals to a 1588 clock source,

each relay protection device and the Flexe switch respectively receive a synchronization result signal sent by a 1588 clock source to obtain the sending time t of a clock synchronization response signal₃And clock-synchronized response signal reception time t₄；

Each relay protection device and the Flexe switch respectively send time t through a synchronous signal₁And a synchronization signal reception time t₂Clock synchronization response signal transmission time t₃And clock-synchronized response signal reception time t₄Calculating the time Offset of each clock source and the 1588 clock source;

and each relay protection device and each Flexe switch calibrate their own clock according to the time Offset, so that the Flexe switches and the relay protection devices keep clock synchronization.

5. The delay control method for relay protection service in power communication according to claim 4, wherein the time Offset calculation formula is:

and obtaining the time offset between the relay protection equipment or the Flexe switch and the 1588 clock source according to a formula.

6. The delay control method for the relay protection service in power communication according to claim 1, wherein the process of sending the sampling data message by the relay protection device at the opposite end through the FlexE slice network is as follows:

initializing a sampling data message by opposite-end relay protection equipment, wherein a sampling value is data of a self-collected power grid transmission line, a frame timestamp is a self timestamp, and the delay accumulation is 0; the relay protection equipment at the opposite end sends the sampling data message to a Flexe switch in a Flexe slice network;

the Flexe switch receives the sampled data message, calculates the difference between the timestamps of the Flexe switch and the relay protection equipment at the opposite terminal according to the value of the timestamp of the Flexe switch and the value of the frame timestamp in the message, accumulates the difference between the timestamps into a delay accumulated field in the message, and updates the frame timestamp field in the message by using the timestamp of the Flexe switch; sending the re-encapsulated sampling data message to other Flexe switches in the slice network;

and repeating the processes to transmit the sampled data message backwards step by step along a Flexe slice network transmission path until the sampled data message is transmitted to the relay protection equipment.

7. The delay control method for the relay protection service in power communication according to claim 6, further comprising:

and if the Flexe slice network has network faults, triggering protection switching, and transmitting the sampling data messages step by adopting a standby line in the Flexe slice network.

8. The delay control method for the relay protection service in power communication according to claim 1, wherein the step of obtaining, by the relay protection device, the sampling value synchronously collected with the opposite terminal according to the total path delay comprises:

the relay protection equipment judges whether the total path time delay meets the time delay requirement or not;

if the time delay requirement is met, directly sampling the power grid transmission line to obtain a sampling numerical value;

and if the delay requirement is not met, inquiring corresponding sampling data from the historical sampling data by taking the current timestamp and the total path delay difference value as an inquiry condition to obtain a sampling value.

9. A relay protection device, comprising:

the clock synchronization module is used for carrying out clock synchronization on the clock synchronization module, each relay protection device and the Flexe switch in the transmission ring network;

the data receiving module is used for receiving a sampled data message sent by the opposite-end relay protection device through a Flexe slice network, wherein the sampled data message comprises a sampling numerical value, a frame timestamp and a delay accumulation;

the data analysis module is used for analyzing the sampled data message to obtain a sampling value and a delay accumulation, wherein the time value of the delay accumulation is the accumulation of the difference of frame timestamps of two adjacent communication parties on a transmission path and is used as the total path time delay from the opposite end to the relay protection equipment;

and the synchronous acquisition module is used for acquiring a sampling numerical value synchronously acquired with the opposite terminal according to the total path time delay.

10. A power communication relay protection service time delay control system is characterized by comprising: the system comprises a first relay protection device, a second relay protection device and a Flexe slice network formed by a plurality of Flexe exchangers;

the first relay protection equipment and the second relay protection equipment are connected through a Flexe slice network to form a transmission ring network; and each relay protection device in the transmission ring network and the Flexe switch keep clock synchronization;

the first relay protection equipment is used for sending a sampling data message to a Flexe slice network, wherein the sampling data message comprises a sampling numerical value, a frame timestamp and delay accumulation;

the second relay protection equipment is used for receiving the sampled data message transmitted through the Flexe slice network, analyzing the sampled data message to obtain a sampling value and a delay accumulation, wherein the time value of the delay accumulation is the accumulation of the difference of frame timestamps of two adjacent communication parties on a transmission path and is used as the total path time delay from the first relay protection equipment to the second relay protection equipment; and obtaining a sampling numerical value synchronously acquired with the opposite terminal according to the total path time delay.

Technical Field

The invention belongs to the technical field of micro-grids, and particularly relates to a time delay control method for power communication relay protection service under a FlexE (Flexible Ethernet) bearing framework, a time delay control system for the power communication relay protection service under the FlexE bearing framework, and relay protection equipment.

Background

The electric power system is an electric energy production and consumption system consisting of links such as power generation, power transformation, power transmission, power distribution and power utilization, and the safety and reliability of a power grid are very important along with the fact that power supply covers the aspects of social production and life. The relay protection is used as a first defense line of the power system, so that the fault state can be quickly detected, the fault can be quickly and automatically isolated, the safety of a power grid is effectively guaranteed, and the fault range is prevented from being expanded. Relay protection can be classified into: transmission line protection and main equipment (such as generators, transformers, busbars and the like) protection. The transmission line protection can be divided into overcurrent protection and pilot protection (such as distance protection and optical fiber differential protection) according to the principle. The optical fiber differential protection has the advantages of short action time, accurate fault judgment, small protection dead zone, effective prevention of override trip and the like, meets the requirements of relay protection on speed, selectivity and sensitivity, and is preferably used as the main protection of a power transmission line when an optical fiber communication channel is provided. In order to prevent the transmission line from generating network congestion and increasing delay, which causes response delay of the relay protection device, the power communication network has been researched and applied to the FlexE technology which can be time sliced. The FlexE time slice can physically separate data streams of different services, so that data transmission networks of different services are not influenced by each other.

The existing delay control method mainly adopts a mode of estimating the delay of a message in a traditional switch and controlling the forwarding time of the message by combining the estimated delay. With the rapid development of the energy internet, the power communication network is increasingly complex. A great challenge is posed to the conventional power communication network. When the power service data is very huge, which causes network congestion and link disconnection, the existing delay compensation method is not enough to meet the delay requirement of the relay protection equipment.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides a time delay control method for power communication relay protection service under a Flexe bearing structure.

In order to solve the technical problems, the invention provides the following technical scheme.

In a first aspect, the present invention provides a delay control method for relay protection service in power communication, where each relay protection device is connected to form a transmission ring network through a FlexE slice network formed by a plurality of FlexE switches, and the delay control method when the relay protection device executes the relay protection service includes the following steps:

clock synchronization is carried out on each relay protection device and a Flexe switch in the transmission ring network;

the method comprises the steps that a relay protection device receives a sampling data message sent by an opposite terminal relay protection device through a Flexe slice network, wherein the sampling data message comprises a sampling numerical value, a frame timestamp and a delay accumulation;

the relay protection equipment analyzes the sampled data message to obtain a sampling value and a delay accumulation, wherein the time value of the delay accumulation is the accumulation of the difference of frame timestamps of two adjacent communication parties on a transmission path and is used as the total path time delay from the opposite end to the relay protection equipment;

and the relay protection equipment obtains a sampling value synchronously acquired with the opposite terminal according to the total path time delay.

Optionally, the method further comprises:

the relay protection equipment judges whether the power grid transmission line has a fault according to the consistency of the sampling values of the relay protection equipment and the opposite terminal, and triggers corresponding protection actions if the fault is judged.

Optionally, the clock synchronization of each relay protection device and the FlexE switch in the transmission ring network includes:

and performing clock synchronization on each relay protection device and the Flexe switch in the transmission ring network through a 1588 clock source.

Optionally, the clock synchronization of each relay protection device and the FlexE switch in the transmission ring network by the 1588 clock source includes:

each Flexe switch of each relay protection device receives a clock synchronization signal sent by a 1588 clock source respectively to obtain synchronization signal sending time t₁And a synchronization signal reception time t₂；

Each relay protection device and the Flexe exchanger respectively send clock synchronization response signals to a 1588 clock source,

each relay protection device and the Flexe switch respectively receive a synchronization result signal sent by a 1588 clock source to obtain the sending time t of a clock synchronization response signal₃And clock-synchronized response signal reception time t₄；

Relay protection devices and Flexe exchangeThe machines respectively transmit time t by synchronous signals₁And a synchronization signal reception time t₂Clock synchronization response signal transmission time t₃And clock-synchronized response signal reception time t₄Calculating the time Offset of each clock source and the 1588 clock source;

and each relay protection device and each Flexe switch calibrate their own clock according to the time Offset, so that the Flexe switches and the relay protection devices keep clock synchronization.

Optionally, the time Offset calculation formula is:

and obtaining the time offset between the relay protection equipment or the Flexe switch and the 1588 clock source according to a formula.

Optionally, the process that the peer relay protection device sends the sampled data message through the FlexE slice network is as follows:

initializing a sampling data message by opposite-end relay protection equipment, wherein a sampling value is data of a self-collected power grid transmission line, a frame timestamp is a self timestamp, and the delay accumulation is 0; the relay protection equipment at the opposite end sends the sampling data message to a Flexe switch in a Flexe slice network;

the Flexe switch receives the sampled data message, calculates the difference between the timestamps of the Flexe switch and the relay protection equipment at the opposite terminal according to the value of the timestamp of the Flexe switch and the value of the frame timestamp in the message, accumulates the difference between the timestamps into a delay accumulated field in the message, and updates the frame timestamp field in the message by using the timestamp of the Flexe switch; sending the re-encapsulated sampling data message to other Flexe switches in the slice network;

and repeating the processes to transmit the sampled data message backwards step by step along a Flexe slice network transmission path until the sampled data message is transmitted to the relay protection equipment.

Optionally, the method further comprises:

and if the Flexe slice network has network faults, triggering protection switching, and transmitting the sampling data messages step by adopting a standby line in the Flexe slice network.

Optionally, the obtaining, by the relay protection device according to the total path delay, a sampling value synchronously acquired with the opposite terminal includes:

the relay protection equipment judges whether the total path time delay meets the time delay requirement or not;

if the time delay requirement is met, directly sampling the power grid transmission line to obtain a sampling numerical value;

and if the delay requirement is not met, inquiring corresponding sampling data from the historical sampling data by taking the current timestamp and the total path delay difference value as an inquiry condition to obtain a sampling value.

In a second aspect, the present invention further provides a relay protection device, including:

the clock synchronization module is used for carrying out clock synchronization on the clock synchronization module, each relay protection device and the Flexe switch in the transmission ring network;

the data receiving module is used for receiving a sampled data message sent by the opposite-end relay protection device through a Flexe slice network, wherein the sampled data message comprises a sampling numerical value, a frame timestamp and a delay accumulation;

the data analysis module is used for analyzing the sampled data message to obtain a sampling value and a delay accumulation, wherein the time value of the delay accumulation is the accumulation of the difference of frame timestamps of two adjacent communication parties on a transmission path and is used as the total path time delay from the opposite end to the relay protection equipment;

and the synchronous acquisition module is used for acquiring a sampling numerical value synchronously acquired with the opposite terminal according to the total path time delay.

The specific implementation scheme of each module in the equipment of the invention refers to the specific step processing procedure of the method.

In a third aspect, the present invention provides a delay control system for relay protection service in power communication, including: the system comprises a first relay protection device, a second relay protection device and a Flexe slice network formed by a plurality of Flexe exchangers;

the first relay protection equipment and the second relay protection equipment are connected through a Flexe slice network to form a transmission ring network; and each relay protection device in the transmission ring network and the Flexe switch keep clock synchronization;

the first relay protection equipment is used for sending a sampling data message to a Flexe slice network, wherein the sampling data message comprises a sampling numerical value, a frame timestamp and delay accumulation;

the second relay protection equipment is used for receiving the sampled data message transmitted through the Flexe slice network, analyzing the sampled data message to obtain a sampling value and a delay accumulation, wherein the time value of the delay accumulation is the accumulation of the difference of frame timestamps of two adjacent communication parties on a transmission path and is used as the total path time delay from the first relay protection equipment to the second relay protection equipment; and obtaining a sampling numerical value synchronously acquired with the opposite terminal according to the total path time delay.

The concrete implementation scheme of each device in the system of the invention is shown in the concrete step processing procedure of the method.

Compared with the prior art, the invention has the following beneficial effects:

1) the data transmission delay (total path delay) of the Flexe slice network between two relay protection devices can be accurately measured.

2) When network fluctuation occurs or network disconnection occurs, the relay protection equipment can adjust sampling time according to data transmission delay, and synchronous sampling is achieved.

3) Physical isolation of a network transmission path can be realized by the Flexe time network slice, so that the risks of transmission network blockage and time delay increase of the relay protection equipment are effectively reduced, and double insurance is provided for meeting the time delay requirement of the relay protection equipment.

Drawings

Fig. 1 is a time synchronization schematic diagram of a FlexE switch/relay protection device;

FIG. 2 is a ring network topology in normal operation;

fig. 3 is a flowchart of a delay control method for power communication service under a FlexE bearer architecture;

fig. 4 is a network topology when protection switching occurs;

FIG. 5 is a schematic diagram of an encapsulated Flexe frame structure;

fig. 6 is a general flow of a delay control method for power communication service under a FlexE bearer architecture.

Detailed Description

The invention is further described below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.

The relay protection system communication time delay control method is characterized in that ring network protection switching is triggered aiming at an optical fiber transmission fault of relay protection equipment, so that the symmetry of a loop is broken, the measurement work of the relay protection equipment is influenced due to the fact that the time delay of two relay protection equipment is asymmetric, the traditional switch in a relay protection group ring network is improved, the communication time delay control method of the relay protection system fusing 1588 clock synchronization technology and adaptive to the Flexe switch is achieved, and the relay protection equipment cannot make wrong response actions due to the fact that the measurement of the relay protection equipment is influenced by network faults.

Example 1

In the embodiment of the invention, a time delay control method for power communication service based on fusion of a Flexe technology and a looped network networking architecture is provided, relay protection equipment can acquire the total path time delay of a message passing through all switch equipment in a Flexe network slice from relay protection equipment on the other side according to the received message, and the relay protection equipment adjusts sampling time through the total path time delay to ensure synchronous measurement of the two relay protection equipment.

The specific implementation contents are as follows, the general flow is shown in fig. 6, and the specific implementation flow is shown in fig. 3:

step 1, enabling a 1588 clock source to realize clock synchronization of a Flexe switch and relay protection equipment in a relay protection equipment transmission ring network through an IEEE-1588 protocol.

A topological structure of a relay protection device transmission ring network is shown in fig. 2, the relay protection device transmission ring network in the embodiment of the present invention includes four FlexE switches and two relay protection devices, which are respectively marked as a FlexE switch A, FlexE switch B, FlexE switch C, FlexE switch D; the relay protection device comprises a first relay protection device and a second relay protection device. And the relay protection devices are connected through a Flexe slice network. After the Flexe technology is adopted, different Flexe time slices can be distributed to different services, one service of the time slices is unique, and other services cannot occupy. Risks caused by network congestion can be greatly reduced after the FlexE technology is adopted for network transmission of the relay protection equipment.

In the embodiment of the invention, a 1588 Clock source is adopted to realize the Clock synchronization of the Flexe switch/the relay protection equipment, the 1588 Clock source is a Master Clock (Master Clock), and the clocks of the Flexe switch and the relay protection equipment are Slave clocks (Slave Clock). And providing a time reference for subsequent time delay compensation.

1588 the clock source realizes time synchronization of 10ns level, as shown in fig. 1, the specific process of clock synchronization is:

step 1, sending clock synchronization signals to all relay protection devices and a Flexe switch in a relay protection device transmission ring network by a 1588 clock source.

And step 2, receiving clock synchronization signals by all relay protection devices and a Flexe switch in a relay protection device transmission ring network to respectively obtain sending time t of 1588 clock source synchronization signals₁And the time t of receiving the synchronous signal of each equipment and the Flexe switch₂Then the transmission time difference t of the synchronous signal can be obtained_ms。

And step 3, each relay protection device and the Flexe switch respectively send clock synchronization response signals to the 1588 clock source.

Step 4, respectively receiving clock synchronization response signals from each relay protection device and the Flexe switch by the 1588 clock source to respectively obtain sending time t of the clock synchronization response signals₃And clock-synchronized response signal reception time t₄The transmission time difference t of the synchronous response signal can be obtained_sm。

And 5, sending a synchronization result signal to the relay protection equipment and the Flexe switch by the 1588 clock source, and respectively sending t to the relay protection equipment and the Flexe switch₁、t₂、t₃And t₄And sending the signals to corresponding relay protection equipment and a Flexe switch.

Step 6, the Flexe exchanger and the relay protection equipment pass through t₁、t₂、t₃And t₄Calculating the time Offset of each clock source and the 1588 clock source, and calibrating the time according to the Offset so that the Flexe switch and the relay protectionThe equipment keeps clock synchronization;

let Offset be two clock differences and Delay be the synchronization signal transmission Delay. Then there are:

through formula transformation, we can obtain:

and obtaining the time Offset between the relay protection equipment or the Flexe switch and a standard 1588 clock source, and adjusting the clock of the relay protection equipment or the Flexe switch according to the time Offset.

And 2, the relay protection equipment sends a sampling data message to the relay protection equipment at the opposite end through a slice network (transmission ring network) defined by the Flexe switch, and the total path time delay of the relay protection equipment transmission ring network is calculated.

And the relay protection equipment judges whether the power grid transmission line has a fault according to the sampling value, and the service function of the relay protection equipment is the fault. If the first relay protection device sends the current at a certain time, the current value is sent to the second relay protection device, the second relay protection device obtains the current value at the same moment and compares the two current values to judge whether the power grid transmission link works normally or not, and if the two current values are not consistent, the power grid is judged to be abnormal, so that relay protection action is triggered.

In the embodiment of the present invention, three fields, namely a frame timestamp field, a delay accumulation field, and a frame carrier field, are encapsulated in a frame structure of a sample data packet, as shown in a schematic diagram of an encapsulated FlexE frame structure in fig. 5. And the frame carrier field is a sampling numerical value obtained by sampling of the relay protection equipment.

In the transmission process in the ring network, the Flexe switch receives the data frame, obtains a frame timestamp value in the data frame, accumulates the difference between the timestamp of the current Flexe switch and the frame timestamp to a delay accumulation field, and sets the timestamp field in the data frame structure as the timestamp of the current Flexe switch.

When the transmission ring network is normal, a sampling data transmission route between the relay protection devices is shown in fig. 2, and a route from the first relay protection device to the second relay protection device is the first relay protection device-FlexE switch a-FlexE switch B-FlexE switch C-second relay protection device. The path from the second relay protection device to the first relay protection device is the second relay protection device-Flexe switchboard C-Flexe switchboard D-Flexe switchboard A-first relay protection device.

Taking the transmission process from the first relay protection device to the second relay protection device as an example, the process of measuring the total path time delay from the first relay protection device to the second relay protection device at this time is as follows:

and 7, the first relay protection equipment sends a sampling data message to the second relay protection equipment, the first relay protection equipment needs to initialize a frame timestamp field and a delay accumulation field in a sampling data message frame structure, the delay accumulation field is initialized to 0, the first relay protection equipment encapsulates the timestamp of the first relay protection equipment in the frame timestamp field of the data frame (namely, the frame timestamp field is initialized to the timestamp of the first relay protection equipment), and the first relay protection equipment sends the data frame to the Flexe switch A.

And 8, calculating the difference between the timestamp of the Flexe switch A and the timestamp of the first relay protection device according to the timestamp of the Flexe switch A and the field value of the frame timestamp in the received frame result, accumulating the difference between the timestamps to a delay accumulation field in a frame structure, and then updating the field of the frame timestamp in the frame structure by using the timestamp of the Flexe switch A.

And 9, the Flexe switch A transmits a sampled data message to the Flexe switch B, the Flexe switch B calculates the difference between the timestamps of the Flexe switch B and the Flexe switch A according to the value of the timestamp of the Flexe switch B and the value of the frame timestamp field in the received frame result, accumulates the difference between the timestamps to a delay accumulation field in a frame structure, and then updates the frame timestamp field in the frame structure by using the timestamp of the Flexe switch B.

And step 10, the Flexe switch B transmits a sampled data message to the Flexe switch C, the Flexe switch C calculates the difference between the timestamps of the Flexe switch C and the Flexe switch B according to the value of the timestamp of the Flexe switch C and the value of the frame timestamp field in the received frame result, accumulates the difference between the timestamps to a delay accumulation field in a frame structure, and then updates the frame timestamp field in the frame structure by using the timestamp of the Flexe switch C.

And 11, the Flexe switch C transmits a sampling data message to the second relay protection equipment, the second relay protection equipment calculates the difference between the timestamps of the second relay protection equipment and the Flexe switch C according to the value of the timestamp of the second relay protection equipment and the value of the frame timestamp in the received frame result, and accumulates the difference of the timestamps to a delay accumulation field in a frame structure. And the time value in the delay accumulation field is the total path time delay from the first relay protection device to the link of the second relay protection device.

The total path delay is the sum of the time stamps of all the devices on the path, and in order to save the frame overhead, the invention adopts step-by-step backward transfer to calculate the delay. Instead of recording all the time stamp information of the path in the last level of the frame structure for unified calculation.

When a network fault occurs in a slice network of the FlexE switch, protection switching is triggered, that is, a main line is switched to a standby line from a main line, for example, a main line from the FlexE switch B to the FlexE switch C fails, and the FlexE switch B transmits data to a next stage (the FlexE switch a) by using the standby line. When protection switching occurs, the network topology structure is as shown in fig. 4, and the path from the first relay protection device to the second relay protection device is the first relay protection device-FlexE switch a-FlexE switch B-FlexE switch a-FlexE switch D-FlexE switch C-second relay protection device; the path from the second relay protection device to the first relay protection device is the second relay protection device-Flexe switchboard C-Flexe switchboard D-Flexe switchboard A-first relay protection device. At this time, the path from the first relay protection device to the second relay protection device and the path from the second relay protection device to the first relay protection device are not symmetrical any more.

And 12, respectively receiving the sampling data messages of the relay protection equipment of the opposite side by the relay protection equipment. And the relay protection equipment analyzes the sampled data message to obtain a sampling value and a data frame time delay accumulation field. And obtaining the total path time delay from the first relay protection device to the second relay protection device link.

And 3, adjusting sampling time by the relay protection equipment according to the total path time delay, and realizing the acquisition synchronization of the relay protection equipment at two ends.

And step 13, the second relay protection equipment judges whether the total path time delay meets (is lower than) the time delay requirement of the relay protection equipment for 5ms (the time delay requirement of the relay protection service on the transmission network is 5-10 ms), if the total path time delay meets the time delay requirement, the step 14 is carried out, and if the total path time delay does not meet the time delay requirement, the step 15 is carried out.

And step 14, directly sampling the electrical physical quantity (such as voltage, current, phase and the like) of the power grid transmission line by the second relay protection equipment, and entering step 4.

And step 15, the second relay protection equipment caches the sampling data in the designated time, and the second relay protection equipment subtracts the total path delay from the first relay protection equipment to the second relay protection equipment from the current time stamp of the second relay protection equipment to obtain an inquiry time stamp which is used as an inquiry condition to inquire the corresponding sampling data from the historical sampling data. Therefore, the function of the relay protection equipment at two ends similar to synchronous direct mining is realized.

If the total path delay time exceeds the maximum time record length of the buffer area, the corresponding sampling data cannot be inquired in the data in the historical sampling, the current measurement is invalid, and the next measurement is carried out.

And 4, judging whether the power grid transmission line has a fault or not by the second relay protection device according to the sampling value, and triggering a corresponding protection action by the second relay protection device if the power grid transmission line has the fault.

The steps are from the first relay protection device to the second relay protection device. The process principle from the second relay protection device to the first relay protection device is similar, and the path from the second relay protection device to the first relay protection device is the second relay protection device-Flexe exchanger C-Flexe exchanger D-Flexe exchanger A-first relay protection device. And calculating to obtain the total path time delay from the second relay protection device to the first relay protection device link. And finally, the first relay protection equipment makes corresponding protection action.

When the power grid has a fault, the first relay protection device and the second relay protection device can rapidly cut off the fault line from the power grid by the cut-off switches to remove the fault line, and the middle fault line is prevented from causing larger loss.

The invention has the beneficial effects that:

1) the data transmission delay of a Flexe slice network between two relay protection devices can be accurately measured.

2) When network fluctuation occurs or network disconnection occurs, the relay protection equipment can compensate according to data transmission delay, and synchronous sampling is achieved.

3) The invention takes the Flexe time network slice as the granularity for time delay measurement and control, and can realize the physical isolation of the network transmission path based on the Flexe time network slice, thereby effectively reducing the risks of transmission network blockage and time delay increase of the relay protection equipment and providing double insurance for meeting the time delay requirement of the relay protection equipment.

Example 2

Based on the same inventive concept as embodiment 1, a relay protection device of the present invention includes:

the clock synchronization module is used for carrying out clock synchronization on the clock synchronization module, each relay protection device and the Flexe switch in the transmission ring network;

the data receiving module is used for receiving a sampled data message sent by the opposite-end relay protection device through a Flexe slice network, wherein the sampled data message comprises a sampling numerical value, a frame timestamp and a delay accumulation;

the data analysis module is used for analyzing the sampled data message to obtain a sampling value and a delay accumulation, wherein the time value of the delay accumulation is the accumulation of the difference of frame timestamps of two adjacent communication parties on a transmission path and is used as the total path time delay from the opposite end to the relay protection equipment;

and the synchronous acquisition module is used for acquiring a sampling numerical value synchronously acquired with the opposite terminal according to the total path time delay.

The specific implementation scheme of each module in the equipment of the invention refers to the specific step processing procedure of the method.

Example 3

Based on the same inventive concept as embodiment 1, the invention provides a time delay control system for power communication relay protection service, comprising: the system comprises a first relay protection device, a second relay protection device and a Flexe slice network formed by a plurality of Flexe exchangers;

the first relay protection equipment and the second relay protection equipment are connected through a Flexe slice network to form a transmission ring network; and each relay protection device in the transmission ring network and the Flexe switch keep clock synchronization;

the first relay protection equipment is used for sending a sampling data message to a Flexe slice network, wherein the sampling data message comprises a sampling numerical value, a frame timestamp and delay accumulation;

the second relay protection equipment is used for receiving the sampled data message transmitted through the Flexe slice network, analyzing the sampled data message to obtain a sampling value and a delay accumulation, wherein the time value of the delay accumulation is the accumulation of the difference of frame timestamps of two adjacent communication parties on a transmission path and is used as the total path time delay from the first relay protection equipment to the second relay protection equipment; and obtaining a sampling numerical value synchronously acquired with the opposite terminal according to the total path time delay.

The concrete implementation scheme of each device in the system of the invention is shown in the concrete step processing procedure of the method.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.