Power communication network supply dependence system elasticity control system and method based on importance reconnection

Abstract

The invention provides a power communication network supply dependence system elastic control system and method based on importance reconnection. The system comprises a node importance acquisition module, a reconnection module and an elastic control module. The node importance acquisition module is used for calculating the centrality attribute of nodes in the power communication network supply dependence system which is subjected to cascade failure to obtain the node importance; the reconnection module is used for reconnecting the nodes of the power communication network supply dependence system based on the sequence of the node importance degrees; and the elasticity control module is used for evaluating the elasticity of the power communication network supply dependence system based on the reconnection of the nodes, and completing the dynamic control of the elasticity of the power communication network supply dependence system in the cascade failure process. The node importance is used as the basis of elastic control, so that the elastic control effect of the network is ensured, and the efficiency level of the network is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of reliability engineering, and in particular relates to a power communication network supply dependency system elastic control system and method based on importance reconnection. Background Art

[0002] With the development of technology and the growth of social needs, the connection between power grid and communication network is becoming closer and closer. The power grid provides energy supply to maintain the normal operation of information and communication network, while the information and communication network is responsible for monitoring the status of power facilities, dispatching power resources and providing information support for emergency response. This two-way dependency means that the failure of any system may affect the normal operation of the other system, and then have a wide impact on society. In this context, the power grid and communication network can be abstracted as a supply-dependent system. The supply-dependent system is a special network system, which is characterized by the formation of a "one-to-many" mutual supply and dependency relationship between the nodes between the two network levels. In such a system, the relationship between the nodes is intertwined: a power node not only supplies power to multiple communication nodes, but also requires the communication services provided by multiple communication nodes to maintain its function; vice versa, while providing communication services to multiple power nodes, the communication node also relies on the power provided by these power nodes. In this structure, as long as the communication node can obtain power from any power source, or the power node can obtain the required communication services from any communication site, they can operate normally. Therefore, the power communication network supply-dependent system can be regarded as a complex network structure formed by the coupling of two hierarchical networks. Studying the elastic control of this coupled network plays a vital role and has far-reaching significance in preventing cascading failures in the system and maintaining stable operation of the system.

[0003] However, the current elastic control methods of power communication network supply-dependent systems focus on the design and prevention work before the accident occurs, ignoring the important role of network reconnection in elastic recovery after the accident, and failing to guide the elastic control of the coupled network after the accident occurs. To this end, the present invention intends to address the above deficiencies and provide an elastic control system and method for power communication network supply-dependent systems based on importance reconnection. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a power communication network supply dependent system elastic control system and method based on importance reconnection, taking node importance as the basis for elastic control, thereby ensuring the elastic control effect of the network and improving the network's efficiency level.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] An elastic control system for a power communication network supply-dependent system based on importance reconnection, comprising: a node importance acquisition module, a reconnection module and an elastic control module;

[0007] A node importance acquisition module is used to calculate the centrality attributes of nodes in the power communication network supply dependency system where cascading failure has occurred, and obtain the node importance;

[0008] A reconnection module, used to reconnect nodes of the power communication network supply dependent system based on the order of node importance;

[0009] The elasticity control module is used to evaluate the elasticity of the power communication network supply-dependent system based on node reconnection, and to complete the dynamic control of the elasticity of the power communication network supply-dependent system during cascading failures.

[0010] Preferably, the supply-dependent system includes a power network layer and a communication network layer, both network layers are weightless and directionless network layers, and each network layer adopts a typical Barabási-Albert network structure.

[0011] Preferably, the power network layer is represented as follows:

[0012] G A = <V A ,E A >,

[0013] Among them, G A Represents the power network layer, V A is the collection of nodes in the power network layer, E A Represents the set of edges in the power network layer;

[0014] The communication network layer is represented as follows:

[0015] G B = <V B ,E B >,

[0016] Among them, G B Represents the communication network layer, V B is the collection of nodes in the communication network layer, E B Represents the set of edges in the communication network layer.

[0017] Preferably, in the node importance acquisition module, the centrality attributes of the node include degree centrality, betweenness centrality and closeness centrality.

[0018] Preferably, the node importance acquisition module includes:

[0019] A degree centrality acquisition unit, used to acquire the degree centrality of a preset node based on the number of nodes adjacent to the preset node;

[0020] A betweenness centrality acquisition unit, used for acquiring the betweenness centrality of a preset node based on the number of shortest paths between the two nodes and the number of shortest paths between the two nodes passing through the preset node;

[0021] A closeness centrality acquisition unit, used to acquire the closeness centrality of a preset node based on the connectivity distance between the preset node and other nodes;

[0022] The node importance acquisition unit is used to perform weighted calculation on the degree centrality, betweenness centrality and closeness centrality of the preset node based on the weighting method to obtain the importance of the preset node.

[0023] Preferably, the reconnection module comprises:

[0024] A sorting unit, for sorting nodes in descending order of importance in each network layer of the power communication network supply dependent system;

[0025] The supply-dependent edge adding unit is used to add additional bidirectional supply-dependent edges between node pairs in each network layer without skipping based on the importance ranking of each node at the current time step, until the number of added edges reaches a preset number, thereby completing the reconnection of the nodes.

[0026] Preferably, the elasticity of the power communication network supply dependent system in the elasticity control module is expressed as:

[0027]

[0028] Where N' A is the number of unfailed nodes in the power network layer, N' B is the number of intact nodes in the communication network layer. The number of nodes in the power network layer and the communication network layer are both N.

[0029] The present invention also provides a power communication network supply dependent system elastic control method based on importance reconnection, using an elastic control system, comprising the following steps:

[0030] Calculate the centrality attributes of nodes in the power communication network supply dependency system where cascading failure has occurred, and obtain the node importance;

[0031] Based on the ranking of node importance, the nodes of the power communication network supply-dependent system are reconnected;

[0032] Based on the reconnection of nodes, the resilience of the power communication network supply-dependent system is evaluated, and dynamic control of the resilience of the power communication network supply-dependent system is completed during cascading failures.

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention can restore the elasticity of the coupled network of the supply-dependent system by reconnecting after an accident with good effect, and comprehensively considers the guiding role of different node attributes in the coupled network on elasticity control, which can guide the elasticity control of the supply-dependent system of the power communication network after an accident, improve the network's ability to resist cascading failures, and improve the network's efficiency level. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solution of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0035] Figure 1 A schematic diagram of the structure of a power communication network supply-dependent system elastic control system based on importance reconnection according to an embodiment of the present invention.

[0036] Figure 2 This is a diagram showing the simulation results of various elastic control strategies for the power communication network supply-dependent system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0037] 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.

[0038] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0039] Embodiment 1

[0040] like Figure 1 As shown, a power communication network supply dependent system elastic control system based on importance reconnection includes: a node importance acquisition module, a reconnection module and an elastic control module;

[0041] A node importance acquisition module is used to calculate the centrality attributes of nodes in the power communication network supply dependency system where cascading failure has occurred at a specific time step of network cascading failure, and obtain the node importance;

[0042] A further implementation method is that the power communication network supply dependent system includes a power network layer and a communication network layer, both network layers are weightless and directionless network layers, and each network layer adopts a typical Barabási-Albert network structure.

[0043] A further embodiment is that the power network layer is represented as follows:

[0044] G A = <V A ,E A >,

[0045] Among them, G A Represents the power network layer, V A is the collection of nodes in the power network layer, E A Represents the set of edges in the power network layer;

[0046] The communication network layer is represented as follows:

[0047] G B = <V B ,E B >,

[0048] Among them, G B Represents the communication network layer, V B is the collection of nodes in the communication network layer, E B Represents the set of edges in the communication network layer.

[0049] There is a "multiple supply-dependency" coupling relationship between the nodes of the power network layer and the communication network layer, which is expressed by the following formula:

[0050]

[0051] like It represents the node Is a node of supply, and initially

[0052]

[0053] Formula (2) means that a node is allowed to have multiple supplies.

[0054] According to the cascading failure process of the power communication network supply-dependent system model, if:

[0055]

[0056] It means node Losing all supply, the node Failure, then delete the node All connections and nodes in the communication network layer All supply dependencies of the network are coupled. For nodes in the power network layer, the failure determination method is the same. In addition, if a node is separated from the largest subgroup of the network layer, it will also fail. The deletion of connection and coupling relationships will lead to the propagation of failures.

[0057] A further implementation method is that in the node importance acquisition module, the centrality attribute of the node includes the degree centrality C D (i) Betweenness centrality C BC (i) and closeness centrality C CC (i).

[0058] A further implementation method is that the node importance acquisition module includes:

[0059] The degree centrality acquisition unit is used to acquire the degree centrality C of the preset node based on the number of nodes adjacent to the preset node. D (i); In this embodiment, the degree centrality C of node i is D (i) Calculated by the following formula:

[0060]

[0061] where k i Represents the number of nodes adjacent to node i.

[0062] The betweenness centrality acquisition unit is used to acquire the betweenness centrality C of a preset node based on the number of shortest paths between the two nodes and the number of shortest paths between the two nodes passing through the preset node. BC (i); In this embodiment, the betweenness centrality of node i is calculated by the following formula:

[0063]

[0064] where g st represents the number of shortest paths between node s and node t, g st (i) represents the number of shortest paths between node s and node t passing through node i.

[0065] A closeness centrality acquisition unit is used to acquire the closeness centrality C of a preset node based on the connectivity distance between the preset node and other nodes. CC (i); In this embodiment, the closeness centrality of node i is calculated by the following formula:

[0066]

[0067] where dij Represents the connection distance between node i and node j.

[0068] Depending on the power communication network supply dependency system of interest, the node centrality attributes evaluated may be different. Other centrality attributes, such as the H index, are included in the calculation according to the general methods used in the field of network science and technology.

[0069] The node importance acquisition unit is used to perform weighted calculation on the degree centrality, betweenness centrality and closeness centrality of the preset node based on the weighting method to obtain the importance of the preset node. Specifically, the weighting method is used to add several centrality attributes C1(i), C2(i),…, C m (i) According to the weights ρ1, ρ2, …, ρ m The weighted comprehensive importance C(i) is expressed as:

[0070]

[0071] A reconnection module, used to reconnect nodes of the power communication network supply dependent system based on the order of node importance;

[0072] In a further embodiment, the reconnection module comprises:

[0073] A sorting unit, for sorting nodes in descending order of importance in each network layer of the power communication network supply dependent system;

[0074] The supply dependency edge adding unit is used to add bidirectional supply dependency edges between node pairs of each network layer in sequence and without skipping, based on the importance ranking of each node at the current time step, until the number of added edges reaches a preset number C, and the reconnection of the nodes is completed. In this embodiment, for one of the network layers, the number of added supply dependencies is C / 2.

[0075] The elasticity control module is used to evaluate the elasticity of the power communication network supply-dependent system based on node reconnection, and to complete the dynamic control of the elasticity of the power communication network supply-dependent system during cascading failures.

[0076] A further implementation method is that the elasticity of the power communication network supply dependent system in the elasticity control module is expressed as:

[0077]

[0078] Where N' A is the number of unfailed nodes in the power network layer, N' Bis the number of nodes that have not failed in the communication network layer. The number of nodes in the power network layer and the communication network layer are both N. The elasticity evaluation implementation process is as follows: after the cascading failure of the current time step ends, the number of nodes that have not failed in each network layer in the current state is counted N' A and N' B , according to formula (8), the elasticity of the power communication network supply dependency system at the current time step can be evaluated.

[0079] A further implementation method is to complete the dynamic control process of the elasticity of the power communication network supply-dependent system during the cascading failure process. The steps at any time step are: after the cascading failure of the current time step ends, the node importance acquisition module is used to calculate the comprehensive importance of all nodes in the power communication network supply-dependent system; the reconnection module is used to generate node rankings and complete the addition of supply-dependent edges; the elasticity of the system is evaluated and the next time step is entered.

[0080] Embodiment 2

[0081] Firstly, a typical power communication network supply dependency system model is constructed, and the cascading failure of the established power communication network supply dependency system is induced. Among them, the two network layers in the power communication network supply dependency system are both weightless and directionless networks. Each network layer adopts the typical Barabási-Albert network structure (scale-free network), and each network layer contains 1000 nodes (i.e., N=1000). The number of edges in the two network layers is 1997, and the total number of supply dependency edges between the two network layers is 4575.

[0082] According to the above-constructed power communication network supply-dependent system model, the cascading failure of the system is induced according to the cascading failure rules of the power communication network supply-dependent system. The node ratio of the initial attack on the power communication network supply-dependent system is set to ρ, and nodes are removed according to the ratio ρ. The attack method is a random attack, which causes the network to undergo a cascading failure process according to the above rules.

[0083] For the power communication network supply-dependent system that has experienced cascading failure, the centrality attributes of the nodes in the power communication network supply-dependent system are calculated at a specific time step of the network cascading failure, and then the node importance of the power communication network supply-dependent system is evaluated. In this example, the calculated key node attributes include degree centrality, betweenness centrality, closeness centrality and H index. The specific calculation method follows the general method used in the field of coupled network technology, and the method for calculating the comprehensive importance of the node adopts the weighting method.

[0084] Reconnect the network based on node importance sorting. According to the calculated node importance, sort the nodes in the power network layer and the communication network layer in descending order of importance. According to the importance sorting of each node at the current time step, add additional bidirectional supply dependency edges between the node pairs in the power network layer and the communication network layer, and add them in sequence without skipping until the number of added edges reaches 100 (i.e. C = 100). (For one of the network layers, the number of added supplies is 50).

[0085] Evaluate the resilience of the power communication network supply dependency system. After the cascade failure of the current time step ends, the resilience of the power communication network supply dependency system model is evaluated according to formula (8).

[0086] In this embodiment, the node attack ratio ρ of the power communication network supply-dependent system is gradually increased from 0 to 100% to induce cascading failure, and the supply-dependent connection relationship between nodes is re-added according to the comprehensive importance of the nodes during the cascading failure process, so as to realize a method for controlling the elasticity of the supply-dependent system in cascading failure. The effect is compared with several common methods. Figure 2 shown.

[0087] Compared with other existing dependent system coupled network resilience control technologies, the method of the present invention can restore the resilience of the supply dependent system coupled network by reconnecting after an accident with better effect, and comprehensively considers the guiding role of different node attributes in the coupled network on resilience control, which can guide the resilience control of the power communication network supply dependent system after an accident, improve the network's ability to resist cascading failures, and enhance the network's efficiency level.

[0088] Embodiment 3

[0089] The present invention also provides a power communication network supply dependent system elastic control method based on importance reconnection, using an elastic control system, comprising the following steps:

[0090] Calculate the centrality attributes of nodes in the power communication network supply dependency system where cascading failure has occurred, and obtain the node importance;

[0091] Based on the ranking of node importance, the nodes of the power communication network supply-dependent system are reconnected;

[0092] Based on the reconnection of nodes, the resilience of the power communication network supply-dependent system is evaluated, and dynamic control of the resilience of the power communication network supply-dependent system is completed during cascading failures.

[0093] The embodiments described above are only descriptions of the preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A power communication network supply dependent system elastic control system based on importance reconnection, characterized in that: include: Node importance acquisition module, reconnection module and elasticity control module; The node importance acquisition module is used to calculate the centrality attribute of the node in the power communication network supply dependency system where cascading failure has occurred, and obtain the node importance; The reconnection module is used to reconnect the nodes of the power communication network supply-dependent system based on the ranking of the node importance; The elasticity control module is used to evaluate the elasticity of the power communication network supply-dependent system based on node reconnection, and to achieve dynamic control of the elasticity of the power communication network supply-dependent system during cascading failures.

2. The power communication network supply dependent system elastic control system based on importance reconnection according to claim 1, characterized in that: The supply-dependent system includes a power network layer and a communication network layer. Both network layers are weightless and directionless network layers, and each network layer adopts a typical Barabási-Albert network structure.

3. The power communication network supply dependent system elastic control system based on importance reconnection according to claim 2, characterized in that: The power network layer is represented as follows: G A = <V A ,E A >, Among them, G A Represents the power network layer, V A is the collection of nodes in the power network layer, E A Represents the set of edges in the power network layer; The communication network layer is represented as follows: G B = <V B ,E B >, Among them, G B Represents the communication network layer, V B is the collection of nodes in the communication network layer, E B Represents the set of edges in the communication network layer.

4. The power communication network supply dependent system elastic control system based on importance reconnection according to claim 2, characterized in that: In the node importance acquisition module, the centrality attributes of the node include degree centrality, betweenness centrality and closeness centrality.

5. The power communication network supply dependent system elastic control system based on importance reconnection according to claim 3, characterized in that: The node importance acquisition module includes: A degree centrality acquisition unit, configured to acquire the degree centrality of a preset node based on the number of nodes adjacent to the preset node; A betweenness centrality acquisition unit, configured to acquire the betweenness centrality of a preset node based on the number of shortest paths between the two nodes and the number of shortest paths between the two nodes passing through the preset node; A closeness centrality acquisition unit, used to acquire the closeness centrality of the preset node based on the connectivity distance between the preset node and other nodes; The node importance acquisition unit is used to perform weighted calculation on the degree centrality, the betweenness centrality and the closeness centrality of the preset node based on the weighting method to obtain the importance of the preset node.

6. The power communication network supply dependent system elastic control system based on importance reconnection according to claim 2, characterized in that: The reconnection module comprises: A sorting unit, used to sort the nodes in descending order of importance in each network layer of the power communication network supply dependent system; The supply-dependent edge adding unit is used to add additional bidirectional supply-dependent edges between node pairs in each network layer without skipping based on the importance ranking of each node at the current time step, until the number of added edges reaches a preset number, thereby completing the reconnection of the nodes.

7. The power communication network supply dependent system elastic control system based on importance reconnection according to claim 2, characterized in that: The elasticity of the power communication network supply dependent system in the elasticity control module is expressed as: Where N' A is the number of unfailed nodes in the power network layer, N' B is the number of intact nodes in the communication network layer. The number of nodes in the power network layer and the communication network layer are both N.

8. A method for elastic control of a power communication network supply-dependent system based on importance reconnection, using the elastic control system described in any one of claims 1 to 7, characterized in that: The following steps are involved: Calculate the centrality attributes of nodes in the power communication network supply dependency system where cascading failure has occurred, and obtain the node importance; reconnecting the nodes of the power communication network supply-dependent system based on the ranking of the node importance; Based on the reconnection of nodes, the resilience of the power communication network supply-dependent system is evaluated, and dynamic control of the resilience of the power communication network supply-dependent system is completed during cascading failures.

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