A cluster cooperative ARQ method for smart grid perception layer

Abstract

The present invention belongs to the field of mobile communication technology, and specifically relates to a smart grid perception layer cluster collaborative ARQ method; the method comprises: constructing a smart grid perception layer communication model, dividing sensor nodes into a first type of nodes and a second type of nodes; initializing the total number of retransmissions of the first type of nodes; using a non-collaborative ARQ retransmission allocation algorithm to calculate a retransmission allocation scheme for the second type of nodes; using a full-collaborative method to calculate a retransmission allocation scheme for the first type of nodes; merging the retransmission allocation schemes of the two types of nodes into a power grid ARQ retransmission allocation scheme; updating the total number of retransmissions of the first type of nodes, repeatedly solving the power grid ARQ retransmission allocation scheme, obtaining all power grid ARQ retransmission allocation schemes, selecting a scheme with the smallest transmission link packet loss rate as the optimal power grid ARQ retransmission allocation scheme and executing it; the present invention can meet the low delay requirements of power grid services, reduce the number of data transmission failures, and reduce the energy overhead required for retransmission.

Description

Technical Field

[0001] The present invention belongs to the technical field of mobile communications, and in particular relates to a smart grid perception layer cluster collaborative ARQ method. Background Art

[0002] Smart Grid is an electric power system based on information and communication technology, which aims to realize the high intelligence and automation of power production, transmission, distribution and use. The perception layer of smart grid uses various means including sensors and signal acquisition equipment to collect the state of objects, such as temperature, humidity, current, equipment operation status, etc. At the same time, it can also pass the instructions sent from the upper layer to the equipment actuator to perform specified actions. The perception layer mainly solves the problem of data collection. It is responsible for perceiving external information and responding to upper-layer instructions to complete the unified and standardized access of data through various terminals. The perception layer of smart grid is a multi-hop network system composed of a large number of distributed sensor nodes. Sensor nodes are usually composed of sensors, processors, communication modules and power supplies.

[0003] The biggest difference between wireless communication systems and wired communication systems is that wireless channels are affected by factors such as multipath effects and fading, which can cause fluctuations in signal quality and instability in channel states. In order to improve data transmission reliability and adapt to changes in wireless channels, ARQ (Automatic Repeat reQuest) technology is often used. The ARQ mechanism can detect and correct errors generated during transmission, thereby improving the reliability of data transmission. By sending confirmation information or negative feedback at the receiving end, the sending end can know whether the data is received correctly. If the receiving end does not receive the correct data, the sending end will resend the data. ARQ technology has been widely used as a general data transmission mechanism in sensor networks. Compared with other complex error control technologies, such as forward error correction coding (Forward Error Correction), ARQ has lower implementation and maintenance costs and is suitable for large-scale deployment scenarios such as smart grids. However, with the development of smart grids, services such as fault detection and location, load scheduling and dynamic optimization, security event detection and response, and power market transaction support are all very sensitive to latency. The traditional ARQ retransmission technology with a fixed upper limit on the number of retransmissions can no longer meet the latency requirements. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention proposes a smart grid perception layer cluster collaborative ARQ method, the method comprising:

[0005] S1: Construct the communication model of smart grid perception layer and divide the sensor nodes into first-class nodes and second-class nodes;

[0006] S2: Initialize the total number of retransmissions of the first type of nodes;

[0007] S3: According to the total number of retransmissions of the first type of nodes, a retransmission allocation scheme for the second type of nodes is calculated using a non-cooperative ARQ retransmission allocation algorithm;

[0008] S4: according to the total number of retransmissions of the first type of nodes, a retransmission allocation scheme for the first type of nodes is calculated by a full cooperation method; the retransmission allocation scheme for the first type of nodes and the retransmission allocation scheme for the second type of nodes are combined into a power grid ARQ retransmission allocation scheme;

[0009] S5: Update the total number of retransmissions of the first type of nodes, repeat steps S3 to S4, obtain all power grid ARQ retransmission allocation schemes, select the scheme with the smallest transmission link packet loss rate as the optimal power grid ARQ retransmission allocation scheme and execute it.

[0010] Preferably, the communication model of the smart grid perception layer includes a perception area, a transmission network and a monitoring center; the perception area includes a Sink node and multiple sensors, the sensors collect information to realize real-time monitoring of the health status of the power grid equipment, and the Sink node is responsible for collecting and integrating the data sent from the sensor nodes; the transmission network is responsible for transmitting the data collected from the Sink nodes in the monitoring area to the monitoring center; the monitoring center performs data aggregation and processing, fault monitoring and management, decision support and optimization, security assurance and emergency response, and user service and management.

[0011] Preferably, the sensor node division process includes: dividing the sensor nodes that can know the usage of the number of retransmissions of the previous node into first-category nodes, and dividing the sensor nodes that cannot know the usage of the number of retransmissions of the previous node into second-category nodes; forming multiple first-category node clusters from the first-category nodes, and forming multiple second-category node clusters from the second-category nodes.

[0012] Furthermore, the total number of retransmissions of the first type of nodes initialized is q c The value range is The vector t represents the number of nodes in each first-class node cluster, and the vector L v represents the number of first-class node clusters, L p Indicates the number of nodes of the second type.

[0013] Preferably, step S3 comprises:

[0014] S31: Initialization parameters, including: first matrix A p , the second matrix b p , the total number of retransmissions is q sum , the direct component of the transmission path For Lp The direct component of the sub-link, the number of the second type of nodes L p ;

[0015] S32: Constructing a non-homogeneous linear system A p q p,real =b p , Assign vectors to the number of retransmissions, Indicates L p Number of retransmissions of the sliver link;

[0016] S33: Solve the non-homogeneous linear equations to obtain the retransmission times allocation vector q p,real , for q p,real To make corrections

[0017] S34: Yes Elements in If it is 0, set it to 1; calculate the number of retransmissions exceeded

[0018]

[0019] S35: In The neighbor set of Find the best retransmission times allocation vector in and get the retransmission times allocation scheme for the second type of nodes; where S represents the solution space, Represents vector q p,real and The number of different elements in .

[0020] Furthermore, the first matrix A p It is expressed as:

[0021]

[0022] in, represents an intermediate variable, and P j represents the probability of decoding and forwarding failure of the jth sub-link, P i represents the probability of decoding and forwarding failure of the i-th sub-link, q i represents the number of retransmissions of the ith sublink, q j represents the number of retransmissions of the jth sublink;

[0023] The second matrix b p It is expressed as:

[0024] b p =[0,0,…,q sum -q c ] T .

[0025] Further, the process of finding the optimal retransmission number allocation vector in the neighbor set Y(q) includes:

[0026] In the neighbor set Υ(q), find the solution that satisfies the condition that the larger the direct component of the sublink, the smaller the number of retransmissions as the candidate solution; calculate the packet loss rate of the candidate solution, and take the solution with the smallest packet loss rate as the optimal allocation vector.

[0027] Preferably, the first type of node allocation retransmission scheme calculated by the full cooperation method includes:

[0028] According to the total number of retransmissions of the first-category nodes, the retransmission allocation vector of each first-category node cluster is preliminarily determined using the non-cooperative ARQ retransmission allocation algorithm, and the total number of retransmissions of all nodes in each first-category node cluster is calculated respectively; the total number of retransmissions of each first-category node cluster is used as the number of retransmissions of the source node in the cluster, and the number of retransmissions of the remaining nodes in the cluster is 0.

[0029] Preferably, the calculation formula for the transmission link packet loss rate is:

[0030]

[0031] Among them, p d Indicates the packet loss rate of the transmission link, P k represents the probability of decoding and forwarding failure of the kth transmission sub-link, q k Indicates the number of retransmissions of the kth transmission sublink.

[0032] The beneficial effects of the present invention are:

[0033] 1. The present invention reduces the communication delay between the monitoring center and the sensor nodes of the smart grid perception layer: the present invention reasonably allocates the number of ARQ retransmissions according to the communication quality of the transmission link. The relay node obtains the usage of the ARQ retransmission times of the previous node through a collaborative mechanism, thereby meeting the low-delay requirements of the power grid business while ensuring the reliability of communication.

[0034] 2. The present invention reduces energy consumption: The strategy proposed in the present invention can reduce the number of data transmission failures, reduce the energy overhead required for retransmission, and help save power grid sensor energy and extend battery life.

[0035] 3. The ARQ retransmission number allocation strategy proposed in the present invention is simple, reliable, and highly compatible, and can be widely used in existing smart grid infrastructure. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a flow chart of the smart grid perception layer cluster collaborative ARQ method in the present invention;

[0037] Figure 2Schematic diagram of the communication model of the smart grid perception layer in the present invention. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] The present invention proposes a smart grid perception layer cluster cooperative ARQ method, such as Figure 1 As shown, the method includes the following contents:

[0040] S1: Construct a communication model for the smart grid perception layer and divide sensor nodes into first-class nodes and second-class nodes.

[0041] like Figure 2 As shown in Figure 1, the communication architecture of the smart grid perception layer includes three parts: perception area, transmission network and monitoring center. The perception area includes Sink nodes and various sensors with wireless communication capabilities to achieve real-time monitoring of the health status of power grid equipment. The Sink node is responsible for collecting data sent from the sensor nodes and aggregating, processing and analyzing the data. It can integrate data from multiple sensor nodes, extract useful information, and provide support for subsequent decision-making. The transmission network is responsible for transmitting the data collected from the Sink nodes in the monitoring area to the monitoring center. It provides channels and infrastructure for data transmission to ensure that data can be smoothly transmitted from each sensor node to the monitoring center, realizing centralized data aggregation and processing. The monitoring center mainly performs data aggregation and processing, fault monitoring and management, decision support and optimization, security assurance and emergency response, and user service and management.

[0042] The sensor nodes are divided into first-class nodes and second-class nodes: the sensor nodes that can know the usage of the number of retransmissions of the previous node are divided into first-class nodes, and the sensor nodes that cannot know the usage of the number of retransmissions of the previous node are divided into second-class nodes; if there are multiple consecutive nodes of the same class, they are divided into a cluster, and if there is only a single node of a single class, the single node is a cluster; multiple first-class node clusters are composed of first-class nodes, and multiple second-class node clusters are composed of second-class nodes.

[0043] The total number of ARQ retransmissions of sensors in the sensing area can be determined based on the actual service delay requirements of the power grid. The total number of ARQ retransmissions can be calculated by the formula Obtain, where τ total Refers to the maximum delay allowed by the service, τ p Refers to the delay of relay node processing and sending, τr Refers to the transmission delay of the relay node sending ACK / NACK message. Figure 2 As shown in the figure, after the multi-hop transmission path between the sensor node and the sink node is determined by the routing protocol, the direct component c k ∈(0,1) is used to characterize the signal transmission quality of the k-th hop transmission sub-link. The higher the direct component, the better the signal transmission quality. For the modeling of the wireless channel, the present invention adopts the Rice fading channel model. The direct component of the entire transmission path can be represented by the vector c, q k represents the number of ARQ retransmissions allocated to each transmission link. The channel fading expression is Where i is an imaginary number, g k is the indirect component (1-c k ) and satisfies Gaussian distribution. When the amount of data to be transmitted by the kth transmission sub-link is greater than the channel capacity, decoding and forwarding will fail. Then the probability of decoding and forwarding failure is P k =Pr(R>log2(1+|h k | 2 θ)), where is the average signal-to-noise ratio of the kth transmission sub-link, p d represents the packet loss rate of the transmission link, and R represents the amount of data that the link needs to transmit. Then for an n-hop, the number of retransmissions of the sub-links is q1, q2, ...q n The packet loss rate expression of the transmission link is: According to the decoding forwarding failure probability P of each transmission link k , the traditional ARQ retransmission strategy with a fixed retransmission upper limit can be improved, the number of ARQ retransmissions can be reasonably allocated, and the packet loss rate of the transmission link can be minimized.

[0044] The smart grid perception layer cluster cooperative ARQ method designed by the present invention requires the following theoretical support:

[0045] Theory 1: The packet loss rate PDP of an N-hop network with a direct component LOS vector c and an ARQ allocation vector q is equal to the PDP of a network with a direct component LOS vector π(c) and an ARQ allocation vector π(q), where π: is the permutation operator (F).

[0046] Theory 1 is proved as follows:

[0047] Assume that the conclusion is valid when N=2

[0048]

[0049] Assuming that N=k, the conclusion is reached and any two sub-links are exchanged immediately, and the PDP will not change.

[0050] When N = k + 1:

[0051]

[0052] The LOS vector in the brackets of the simplified result is [c2,c3,…,c k+1 ], the ARQ retransmission allocation vector is [q2,q3,…,q k+1 ], so after replacement, any two links in k hops will not change the PDP (transmission link packet loss rate). It is also necessary to prove that the first sublink with LOS component c1 and the subsequent sublinks with LOS components {c2,c3,…,c k+1 Replacing any sub-link of} will not change the PDP.

[0053] First exchange the LOS components c2 and c k+1 The PDP expression is simplified to:

[0054]

[0055] Then replace the LOS components into c1 and c k+1 The two sub-links of

[0056]

[0057] p d =p′ d

[0058] Theory proven.

[0059] Theory 2: LOS vector is c, and the signal-to-noise ratio is high enough to make The ARQ allocation vector q satisfies the following properties: i <c j , then q i ≥q j ,

[0060] The proof of Theory 2 is as follows:

[0061] The LOS vector c=[c1,c2,…,c i ,…,c j ,…,c N-1 ,c N ], according to the theory, it is replaced by c ′ =[c1,c2,…,c N-1 ,…,c N ,…,c i ,c j ], q i =q j =q, then the link packet loss rate:

[0062]

[0063] Assume that there is an extra ARQ retransmission, and allocate the extra ARQ retransmission to the LOS component c. i ,c j Transmission sub-links, and compare their PDPs:

[0064]

[0065]

[0066] Because c i <c j , P i >P j

[0067] so A <B。

[0068] Theory 2 is proven.

[0069] Theory 3: For an N-hop network with LOS vector c, if and only if the ARQ retransmission allocation vector The minimum PDP is obtained when the following conditions are met:

[0070]

[0071] in

[0072]

[0073] The proof of theory 3 is as follows:

[0074] Get the best ARQ retransmission allocation vector Two neighbor sets of :

[0075]

[0076] Replace the LOS vector with c = [c1, c2, ..., c N-1 ,…,c N ,…,c i ,c j ]

[0077] According to theory 1, the corresponding allocation vector can be replaced as:

[0078]

[0079] because

[0080] Simplified:

[0081]

[0082] Simplifying the first inequality:

[0083]

[0084] make

[0085] Taking the logarithm of both sides and simplifying it gives:

[0086]

[0087] Similarly, we can get the second inequality:

[0088]

[0089] The theory has been proven three times.

[0090] Theory 4: In an N-hop network, the link LOS vector c = [c1, c2, ..c N ], if the full cooperation scheme is adopted, when the ARQ allocation vector is q * =[q sum ,0,…,0], the packet loss rate PDP is the smallest.

[0091] The proof of theory 4 is as follows:

[0092] When N = 2, q = [q1, q2],

[0093] When q=[q1+1,q2-1],

[0094]

[0095] Therefore, the number of retransmissions on the first link increases, while the number of retransmissions on the second link decreases. It can be obtained that when N = 2, when q = [q sum ,0], PDP is the smallest.

[0096] Assume that the conclusion holds when N = k. When N = k + 1, the ARQ retransmission allocation vector is q = [q1, q2, …q k+1 ], the k+1 nodes after that are equivalent to one node, denoted as R v , the number of retransmissions allocated to it is The packet loss rate of this virtual transmission link is recorded as PDP v (q sum,v ). Then the packet loss rate of these two virtual transmission links is

[0097] Fix P1 and q1, and only need to minimize PDP v (q sum,v+j-1), according to the assumption, the ARQ retransmission times allocation vector of the k-hop network is [q sum -q1,0,…,0], the packet loss rate of the k-hop network is the smallest. At this time, the ARQ retransmission allocation vector of the total transmission link is [q1,q sum -q1,0,…,0].

[0098] Then continue to increase q1 and decrease q sum -q1

[0099]

[0100] So when N=k+1, the ARQ retransmission times allocation vector is q=[q sum ,0,…,0], PDP is the smallest.

[0101] Theory four is proven.

[0102] S2: Initialize the total number of retransmissions of the first type of nodes to q c .

[0103] The total number of retransmissions by the first type of nodes is q c The value range is The vector t represents the number of nodes in each first-class node cluster, and the vector L v represents the number of first-class node clusters, L p Indicates the number of nodes of the second type. Preferably, q can be initialized c is the minimum or maximum value.

[0104] S3: According to the total number of retransmissions of the first type of nodes, a retransmission allocation scheme for the second type of nodes is calculated using a non-cooperative ARQ retransmission allocation algorithm.

[0105] According to theory 3, the ARQ retransmission allocation problem can be simplified to the following mathematical problem:

[0106] 1) The number of retransmissions of the i-th link and the j-th link satisfies the relationship:

[0107] 2) The number of retransmissions is a positive integer and each link has at least one retransmission opportunity:

[0108] 3) The total number of retransmissions is q sum :q1+q2+q3+…+q N =q sum .

[0109] Next, define This problem can be solved by the nonhomogeneous linear equation system Aq real = b, where q real=[q1,q2,…,q N ] T ,b=[0,0,…,q sum ] T ,

[0110] The optimized ARQ retransmission allocation vector q can be obtained real =A -1 b.

[0111] Define the concept of search space, only in Determine the ARQ retransmission allocation vector q. For a q∈S, is the neighbor solution set, where Indicates the number of different elements in two vectors.

[0112] The process of calculating the retransmission number allocation scheme for the second type of nodes using the non-cooperative ARQ retransmission number allocation algorithm includes:

[0113] S31: Initialization parameters, including: first matrix A p , the second matrix b p , the total number of retransmissions is q sum , the direct component of the transmission path For L p The direct component of the sub-link, the number of the second type of nodes L p .

[0114] The first matrix A p It is expressed as:

[0115]

[0116] in, represents an intermediate variable, and P j represents the probability of decoding and forwarding failure of the jth sub-link, p i represents the probability of decoding and forwarding failure of the i-th sub-link, q i represents the number of retransmissions of the ith sublink, q j represents the number of retransmissions of the j-th sublink;

[0117] The second matrix b p It is expressed as:

[0118] b p =[0,0,…,q sum -q c ] T

[0119] S32: Constructing a non-homogeneous linear system A p qp,real =b p , Assign vectors to the number of retransmissions, Indicates L p Number of retransmissions on a sublink.

[0120] S33: Solve the non-homogeneous linear equations to obtain the retransmission times allocation vector q p,real , for q p,real To make corrections

[0121] The number of retransmissions must be a positive integer, so modify the retransmission allocation vector Indicates rounding up.

[0122] S34: Yes Elements in If it is 0, set it to 1; calculate the number of retransmissions exceeded

[0123] S35: In The neighbor set of Find the best retransmission times allocation vector in and get the retransmission times allocation scheme for the second type of nodes; where S represents the solution space, Represents vector q p,real and The number of different elements in .

[0124] The process of finding the optimal retransmission count allocation vector in the neighbor set Υ(q) includes:

[0125] According to Theory 2, when the total number of retransmissions is fixed, find the solution in the neighbor set Υ(q) that satisfies the condition that the larger the direct component of the sublink, the smaller the number of retransmissions as a candidate solution; calculate the packet loss rate of the candidate solution, and take the solution with the smallest packet loss rate as the optimal allocation vector.

[0126] S4: according to the total number of retransmissions of the first type of nodes, a retransmission allocation scheme for the first type of nodes is calculated by using a full cooperation method; the retransmission allocation scheme for the first type of nodes and the retransmission allocation scheme for the second type of nodes are combined into a power grid ARQ retransmission allocation scheme.

[0127] In the full-cooperative method, the field of the number of ARQ retransmissions used is added to the message forwarded by the intermediate node, so that the subsequent nodes can increase the number of available retransmissions while meeting the delay requirements, thereby improving communication reliability; the full-cooperative method is supported by Theory 4.

[0128] The first type of node allocation retransmission scheme calculated by the full cooperation method includes:

[0129] According to the total number of retransmissions of the first-class nodes, the retransmission allocation vector q = [q1, q2, …, q k ], calculate the total number of retransmissions of all nodes in each first-class node cluster, i.e., q1+q2+…+q k ; The total number of retransmissions of each first-type node cluster is taken as the number of retransmissions of the source node in the cluster, and the number of retransmissions of the remaining nodes in the cluster is 0.

[0130] The previous node transmits the current remaining retransmission times to the next node, and the remaining nodes can only use the remaining retransmission times.

[0131] S5: Update the total number of retransmissions of the first type of nodes, repeat steps S3 to S4, obtain all power grid ARQ retransmission allocation schemes, select the scheme with the smallest transmission link packet loss rate as the optimal power grid ARQ retransmission allocation scheme and execute it.

[0132] Update the total number of retransmissions of the first type of nodes, the value is Repeat steps S3 to S4 until the total number of retransmissions of the first type of nodes has traversed all values ​​within the value range, and all power grid ARQ retransmission allocation schemes are obtained. Calculate the transmission link packet loss rate of each power grid ARQ retransmission allocation scheme, and select the scheme with the smallest transmission link packet loss rate as the optimal power grid ARQ retransmission allocation scheme. The system executes the optimal power grid ARQ retransmission allocation scheme, which can meet the low latency requirements of power grid services while ensuring communication reliability, while reducing the number of data transmission failures and reducing the energy overhead required for retransmission.

[0133] The above embodiments further illustrate the purpose, technical solutions and advantages of the present invention in detail. It should be understood that the above embodiments are only preferred implementation modes of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made to the present invention within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A smart grid perception layer cluster collaborative ARQ method, characterized in that: include: S1: Construct the communication model of smart grid perception layer and divide the sensor nodes into first-class nodes and second-class nodes; The sensor node division process includes: dividing the sensor nodes that can know the usage of the number of retransmissions of the previous node into the first type of nodes, and dividing the sensor nodes that cannot know the usage of the number of retransmissions of the previous node into the second type of nodes; forming a plurality of first type node clusters from the first type of nodes, and forming a plurality of second type node clusters from the second type of nodes; S2: Initialize the total number of retransmissions of the first type of nodes; S3: According to the total number of retransmissions of the first type of nodes, a retransmission allocation scheme for the second type of nodes is calculated using a non-cooperative ARQ retransmission allocation algorithm; including: S31: Initialization parameters, including: first matrix A p , the second matrix b p , the total number of retransmissions is q sum , the direct component of the transmission path For L p The direct component of the sub-link, the number of the second type of nodes L p ; S32: Constructing a non-homogeneous linear system A p q p,real =b p , Assign vectors to the number of retransmissions, Indicates L p Number of retransmissions of the sliver link; S33: Solve the non-homogeneous linear equations to obtain the retransmission times allocation vector q p,real , for q p,real To make corrections S34: Yes Elements in If it is 0, set it to 1; calculate the number of retransmissions exceeded S35: In The neighbor set of Find the best retransmission times allocation vector in and get the retransmission times allocation scheme for the second type of nodes; where S represents the solution space, Represents vector q p,real and The number of distinct elements in ; S4: according to the total number of retransmissions of the first type of nodes, a retransmission allocation scheme for the first type of nodes is calculated by a full cooperation method; the retransmission allocation scheme for the first type of nodes and the retransmission number allocation scheme for the second type of nodes are combined into a power grid ARQ retransmission number allocation scheme; the retransmission allocation scheme for the first type of nodes calculated by a full cooperation method includes: According to the total number of retransmissions of the first-class nodes, the retransmission allocation vector of each first-class node cluster is preliminarily determined using the non-cooperative ARQ retransmission allocation algorithm, and the total number of retransmissions of all nodes in each first-class node cluster is calculated respectively; the total number of retransmissions of each first-class node cluster is used as the number of retransmissions of the source node in the cluster, and the number of retransmissions of the remaining nodes in the cluster is 0; S5: Update the total number of retransmissions of the first type of nodes, repeat steps S3 to S4, obtain all power grid ARQ retransmission allocation schemes, select the scheme with the smallest transmission link packet loss rate as the optimal power grid ARQ retransmission allocation scheme and execute it.

2. A smart grid perception layer cluster collaborative ARQ method according to claim 1, characterized in that: The communication model of the smart grid perception layer includes a perception area, a transmission network and a monitoring center; the perception area includes a Sink node and multiple sensors, the sensors collect information to realize real-time monitoring of the health status of power grid equipment, and the Sink node is responsible for collecting and integrating data sent from the sensor nodes; the transmission network is responsible for transmitting the data collected from the Sink nodes in the monitoring area to the monitoring center; the monitoring center performs data aggregation and processing, fault monitoring and management, decision support and optimization, security assurance and emergency response, and user service and management.

3. The smart grid perception layer cluster collaborative ARQ method according to claim 1, characterized in that: The total number of retransmissions of the first type of node initialized is q c The value range is The vector t represents the number of nodes in each first-class node cluster, and the vector L v represents the number of first-class node clusters, L p Indicates the number of nodes of the second type.

4. The smart grid perception layer cluster collaborative ARQ method according to claim 1, characterized in that: The first matrix A p It is expressed as: in, represents an intermediate variable, and P j represents the probability of decoding and forwarding failure of the jth sub-link, P i represents the probability of decoding and forwarding failure of the i-th sub-link, q i represents the number of retransmissions of the ith sublink, q j represents the number of retransmissions of the j-th sublink; The second matrix b p It is expressed as: b p =[0,0,…,q sum -q c ] T 。 5. The smart grid perception layer cluster collaborative ARQ method according to claim 1, characterized in that: The process of finding the optimal retransmission count allocation vector in the neighbor set Υ(q) includes: In the neighbor set Υ(q), find the solution that satisfies the condition that the larger the direct component of the sublink, the smaller the number of retransmissions as the candidate solution; calculate the packet loss rate of the candidate solution, and take the solution with the smallest packet loss rate as the optimal allocation vector.

6. The smart grid perception layer cluster cooperative ARQ method according to claim 1, characterized in that: The calculation formula of the transmission link packet loss rate is: Among them, p d Indicates the packet loss rate of the transmission link, P k represents the probability of decoding and forwarding failure of the kth transmission sub-link, q k Indicates the number of retransmissions of the kth transmission sublink.

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