Method and system for generating operation scene of power information physical system under deliberate attack

Abstract

The invention belongs to the technical field of power cyber-physical system operation scene generation, and provides a power cyber-physical system operation scene generation method and system under deliberate attacks, and the technical scheme is as follows: constructing a power cyber-physical system topology model; considering a coupling relation between a communication line and a physical line, and evaluating the line importance under an incomplete information condition based on a complex network theory; dynamically analyzing an attack and defense game process of an attacker and a defender based on an attack and defense game theory, and establishing an upper-layer defense model, a middle-layer attack model and a lower-layer defense regulation and control model of the power information physical system under the deliberate attack; and forming a defense-attack-defense regulation and control model under an incomplete information condition, solving to obtain an attack-defense resource allocation scheme under deliberate attack, and generating an operation scene based on Monte Carlo simulation. And the capability of resisting the impact of the deliberate attack event of the system is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of power information-physical system operation scenario generation, and in particular, to a method and system for generating an operation scenario of a power information-physical system under intentional attacks. Background Art

[0003] At present, the mainstream intentional attack methods include not only physical attack methods such as destroying transmission lines, but also information attack methods that interfere with channel transmission. At the same time, with the widespread application of advanced information and communication technology in the generation, transmission, transformation, distribution and use of power systems, the power system relies on a powerful information system all the time to realize the situational awareness and precise control of the power grid. Its form has gradually evolved from the traditional network composed mainly of primary equipment to the power information-physical system with deep coupling between the primary system and the information system. On the one hand, the information system makes the operation and control of the primary system more intelligent and efficient. On the other hand, the close coupling of the two subsystems in structure and function means that disturbances in any subsystem may affect the normal operation of the other subsystem, and even cause faults to propagate alternately between the two subsystems, thus exposing the entire power information-physical system to more risks under intentional attacks. Therefore, improving the emergency response capability of the power information-physical system cannot only focus on the consequences of a primary system failure caused by intentional attacks, but also urgently needs to consider the multiple impacts on the physical system and the information system.

[0004] The main content of the pre-emptive defense strategy arrangement is to strengthen the system structure or function by investing in various hardware, software or human resources, so as to reduce the possible harm caused by extreme events to the system. Common measures include upgrading reinforcement materials to improve the strength of poles and towers; adding visualization devices to strengthen the monitoring of transmission channels. Since defense resources are always limited, it is necessary to formulate the optimal resource allocation plan for intentional attack events to maximize the emergency response capabilities of the system. At present, the attack and defense game model for defense resource allocation in the existing intentional attack scenario: 1. Intentional attacks on power grids often consider the conditions of complete information, that is, it is assumed that both the attacker and the defender know the complete information of the power grid, but in fact it is a dynamic attack and defense game generated under incomplete information conditions; 2. It only targets physical systems and does not consider the impact of information systems under intentional attacks. The attack and defense model constructed on this basis is inaccurate, and the generated operation scenarios are often inconsistent with the actual scenarios. Summary of the invention

[0005] In order to solve at least one technical problem existing in the above-mentioned background technology, the present invention provides a method and system for generating an operating scenario of an electric power information-physical system under a deliberate attack, which considers generating an operating scenario after a deliberate attack for the electric power information-physical system under incomplete information conditions.

[0006] In order to achieve the above object, the present invention adopts the following technical solution: A first aspect of the present invention provides a method for generating an operation scenario of an electric power cyber-physical system under a deliberate attack, comprising the following steps: Based on the topological information obtained in the power grid diagram database, a topological model of the power cyber-physical system is constructed; Combined with the topological model of the power cyber-physical system, the line weighted betweenness is calculated, and the comprehensive importance of the line is calculated based on the line weighted betweenness and line attributes; Based on the attack and defense game theory, the defense resources are quantified, and the upper-layer defense model under intentional attacks is constructed by combining the defense resource allocation strategy that minimizes the expected value of load loss in the power grid. Combined with the comprehensive importance of the lines, the attack resources are quantified, and a mid-level attack model of the attack process under incomplete information conditions is constructed; Based on the attack and defense game theory, the line failure probability is calculated according to the line resource allocation, and the lower-level control model under deliberate attack is constructed; Based on the upper-layer defense model, the middle-layer attack model and the lower-layer control model, the optimal attack and defense resource allocation strategy of the line is solved; The failure probability of the line is calculated based on the optimal attack and defense resource allocation strategy of the line, and the operation scenario of the power cyber-physical system under intentional attack is generated based on the failure probability of the line.

[0007] Furthermore, the calculation process of the line weighted betweenness includes the calculation of the communication line weighted betweenness and the physical line weighted betweenness. The specific calculation process includes: Calculate the weight of the communication line or the weight of the physical line; Calculating a weighted shortest path length based on a weight of a communication line or a weight of a physical line; The weight of the communication line or the weighted betweenness of the physical line is calculated based on the weighted shortest path.

[0008] Furthermore, the formula for the comprehensive importance of the line is: , , , In the formula, For Line The weighted betweenness of the communication line, For Line The weighted betweenness of the physical line, For Node s and t The total number of weighted shortest paths between For Node s and t Passing lines l The number of weighted shortest paths,V is the total number of nodes, is the weight parameter of the autonomously defined communication network, corresponding to is the weight parameter of the physical network.

[0009] Furthermore, the upper layer defense model under deliberate attack is: The optimization goal is to minimize the load shedding of the power grid: , The defense resource constraints that need to be met are: , , , , in, Representing the resource allocation strategy of the grid defender, represents the set of all power nodes, ) is the node after the defense strategy and attack strategy are determined The load shear at Is the defender assigned to the line The number of defensive resources; is the total amount of defensive resources the defender has; Represents the set of all lines. To improve the strength of the tower reinforcement material, To enhance the visualization of channel monitoring, and is the corresponding weight, and the initial value of the line deployment material is The total number of materials is , the minimum value is , the initial value of the line deployment device is The total number of devices is , the minimum value is .

[0010] Furthermore, the middle-level attack model of the attack process under incomplete information conditions is: The goal is to maximize the attack benefit: , The attack resource constraints that need to be met are: , , , , in, Represents the attacker's attack resource allocation strategy; Is the defender assigned to the line The number of defensive resources; The defense resource strategy for the defender in the upper model; After comprehensive evaluation The importance of is the attacker's assignment to the line The number of attack resources; A is the total amount of attack resources; Represents the set of all lines. To destroy the transmission line drone resources, A graphite bomb to interfere with channel transmission. and is the corresponding weight, and the initial value of the attack line drone is The total number of drones is , the minimum value is , the initial value of dropping bombs is , the total number of bombs is , the minimum value is .

[0011] Furthermore, the lower-level control model under deliberate attack is: The actual load shedding amount is minimized: , The constraints include: , , , , , , , in, f represents load shedding measures taken for defenders, represents the set of all power nodes, ) is a node The load shedding capacity, Representation Node The active and reactive power, For Node The load before the event, For Node After the event occurs, the load For Node i The voltage, For Nodej The voltage, Representation Node i and j The conductance and susceptance between Representation Node i and j The voltage angle difference between For Node The active power output of the generator is For Node The reactive power output of the generator, For Node The upper limit of the active power output of the generator, and For Node The upper and lower limits of the reactive power output of the generator, and Line The current and current limits of Indicates the operating status of the line. and Respectively represent nodes i The upper and lower voltage limits.

[0012] Furthermore, based on the upper-layer defense model, the middle-layer attack model and the lower-layer control model, the optimal attack and defense resource allocation strategy of the line is solved, including: Determine the total amount of defense resources and the total amount of attack resources; Formulate a preliminary defense resource allocation strategy based on the upper-layer defense model, and allocate a certain amount of defense resources to each line of the power grid to minimize the load shedding of the power grid; After obtaining the defender's defense strategy, the comprehensive importance of the line is analyzed based on incomplete information conditions, and the attack strategy is determined in combination with the middle-level attack model, with the goal of maximizing the attack benefit; After the defense strategy and attack strategy are determined, the defender executes the control strategy based on the lower-level control model and uses load shedding operations to redistribute the power flow so that the load loss of the power grid is as small as possible.

[0013] A second aspect of the present invention provides a system for generating an operation scenario of an electric power cyber-physical system under a deliberate attack, comprising: A topology building module is used to build a topology model of the power information-physical system based on the topology information obtained in the power grid diagram database; A line comprehensive importance calculation module is used to calculate the line weighted betweenness in combination with the power information-physical system topology model, and calculate the line comprehensive importance based on the line weighted betweenness and line attributes; The defense model building module is used to quantify defense resources based on the attack and defense game theory, and to build an upper-level defense model under deliberate attacks in combination with a defense resource allocation strategy that minimizes the expected value of load loss in the power grid; The attack model building module is used to combine the comprehensive importance of the lines, quantify the attack resources, and build a mid-level attack model of the attack process under incomplete information conditions; The control model building module is used to calculate the line failure probability according to the line resource allocation based on the attack and defense game theory, and to build the lower-level control model under deliberate attack; The operation scenario generation module is used to solve the optimal attack and defense resource allocation strategy of the line based on the upper-level defense model, the middle-level attack model and the lower-level control model; calculate the failure probability of the line based on the optimal attack and defense resource allocation strategy of the line, and generate the operation scenario of the power information-physical system under intentional attack based on the failure probability of the line.

[0014] A third aspect of the present invention provides a computer-readable storage medium.

[0015] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps in the method for generating an operation scenario of an electric power information-physical system under a deliberate attack as described above.

[0016] A fourth aspect of the present invention provides a computer device.

[0017] A computer device comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps in the method for generating an operation scenario of an electric power information-physical system under a deliberate attack as described above are implemented.

[0018] Compared with the prior art, the present invention has the following beneficial effects: 1. Aiming at the problem that traditional defense models do not adequately consider cyber-physical interaction behaviors, the present invention considers physical attacks on power transmission networks and their communication networks, and constructs the defense resource allocation problem of power cyber-physical systems into a three-layer optimization model of defense-attack-defense regulation with the goal of minimizing load shedding. The proposed method can effectively provide the system with the optimal defense resource allocation plan and operation scenario under physical attack scenarios, and improve the system's ability to resist the impact of deliberate attack events.

[0019] 2. The IIDAD three-layer optimization model proposed in the present invention is divided into an upper-layer defense model from the defender's perspective, a middle-layer attack model from the attacker's perspective, and a lower-layer regulation model from the defender's perspective. It takes into account the problem of incomplete information conditions in the attack and defense game process and can effectively cope with the complex changes of the system under extreme events.

[0020] Advantages of additional aspects of the present invention will be given in part in the following description, and in part will become obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0022] Figure 1 It is a flow chart of a method for generating an operation scenario of an electric power cyber-physical system under a deliberate attack provided by an embodiment of the present invention; Figure 2 is a schematic diagram of a power information-physical structure coupling model under a deliberate attack provided by an embodiment of the present invention; Figure 3 is a schematic diagram of a deliberate attack line screening process provided by an embodiment of the present invention; Figure 4 It is a framework diagram of the IIDAD model provided by an embodiment of the present invention; Figure 5 It is a flow chart of solving a three-layer optimization model based on a nested PSO algorithm provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0023] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0024] It should be noted that the following detailed descriptions are all illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0025] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0026] As mentioned in the background technology, the current attack and defense game model for defense resource allocation under the existing intentional attack scenario: 1. Intentional attacks on the power grid often consider the condition of complete information, that is, it is assumed that both the attacker and the defender know the complete information of the power grid, but it is actually a dynamic attack and defense game generated under incomplete information conditions; 2. It only targets the physical system, and does not consider the impact of the information system under intentional attacks. The attack and defense model constructed on this basis is inaccurate, and the generated operating scenarios often do not match the actual scenarios. Therefore, it is urgent to consider the operating scenarios after the intentional attack on the power information-physical system under incomplete information conditions. A method and system for generating operation scenarios of power information-physical systems under deliberate attacks are publicly proposed, and a topological model of power information-physical systems is constructed. Taking into account the coupling relationship between communication lines and physical lines, the importance of lines under incomplete information conditions is evaluated based on complex network theory. The attack and defense game process of attackers and defenders is dynamically analyzed based on the attack and defense game theory, and an upper-level defense model, a middle-level attack model, and a lower-level defense regulation model of power information-physical systems under deliberate attacks are established. A defense-attack-defense regulation model under incomplete information conditions, namely the IIDAD (information-based incomplete defender-attacker-defender) three-layer mathematical programming model, is formed, the attack and defense resource allocation plan under deliberate attacks is solved, and the operation scenario is generated based on Monte Carlo simulation.

[0027] Embodiment 1 like Figure 1 As shown, this embodiment provides a method for generating an operation scenario of a power cyber-physical system under a deliberate attack, comprising the following steps: Step 1: Obtain topological information from the power grid database and build a topological model of the power cyber-physical system; Figure 2 To establish a topological model of power cyber-physical system based on complex network theory, such as Figure 2 As shown, specifically including: The specific stations and lines are abstracted into coupled networks composed of nodes and associations, covering the physical network and the information network. In combination with the structure and functional characteristics of the power system, the power hubs such as power stations and important loads in the physical layer are regarded as physical nodes, and the transmission lines are regarded as the power associations of the nodes to reflect the energy supply relationship of the system. The communication hubs such as the dispatching master station and communication substation in the information layer are regarded as information nodes, and the communication channels are regarded as the information associations of the nodes to reflect the monitoring and control relationship of the physical system: the nodes and edges in the physical network and the information network are regarded as a one-to-one correspondence, and the physical layer and the information layer are deeply coupled. It is assumed that physical attacks will destroy both physical and information components.

[0028] Step 2: Combined with the power cyber-physical system topology model, the line weighted betweenness is calculated, and the comprehensive importance of the line is calculated based on the line weighted betweenness and line attributes; like Figure 3 As shown, the specific steps include: Step 201, calculating the weighted betweenness of the communication line, specifically includes the following steps: Step 211: Calculate the weight of the communication line in the information network. The weight of the communication line is determined by its contribution to the communication connection of the generator node: (1), In the formula, For information network l The weight of the communication line, For the generator node The number of connected communication lines.

[0029] Obviously, if the line is the only communication connection of the generator node, its weight is at most 1.

[0030] Step 2012: Calculate the weighted shortest path length according to the communication line weight: (2), In the formula, the communication line length ,The attacker focuses on the shortest path, and high weight lines correspond to shorter path lengths, and attacks on high weight lines produce more serious consequences.

[0031] Step 2013: Recalculate the route based on the weighted shortest path The weighted betweenness of the communication line : (3), In the formula, For Node s and t The total number of weighted shortest paths between For Node s and t Passing lines l The number of weighted shortest paths.

[0032] Step 202, calculating the weighted betweenness of the physical line, specifically includes the following steps: Similar to the communication line weight assignment, the physical line weight is assigned according to the proportion of the line in the generator connection line and the voltage level of the line: Consider the proportion of physical lines connected to the generator : (4), In the formula, For the generator node The number of physical lines connected. Obviously, if the line is the only physical connection to the generator node, its weight is 1 at most.

[0033] Consider the line voltage level correction factor : (5), In the formula, For Line l The voltage level, It is the highest voltage level of the lines in the network. The voltage level directly reflects the load capacity and importance of the line.

[0034] Then the physical line weight can be expressed as: (6), Combining equations (4) and (5), the complete expression of the physical line weight can be obtained as follows: (7), Calculate the weighted shortest path length based on the obtained physical line weight: (8), Where, the physical line length .

[0035] Recalculate routes based on weighted shortest paths ( is the total number of lines) : (9), In the formula, For Node s and t The total number of weighted shortest paths between For Node s and t Passing lines l The number of weighted shortest paths, V is the total number of nodes; Step 203: Calculate the comprehensive importance of the line based on the weighted betweenness of the communication network and the physical network : (10), In the formula, is the weight parameter of the autonomously defined communication network, corresponding to is the weight parameter of the physical network, which is determined according to the actual system requirements. adjustments.

[0036] Step 3: Establish an upper-level defense model from the defender’s perspective based on the attack-defense game theory; Based on the attack-defense game theory, a defense model from the defender's perspective is established, defense resources are quantitatively evaluated to form a defense strategy, and a defense process simulation framework under deliberate attacks is constructed; Based on the attack and defense game theory, the enemy that causes damage to the power grid or information network is regarded as an "attacker", and the automatic maintenance program or manager of the power information physics is assumed to be a "defender". The defense process of the power information physics system can be regarded as an attack and defense game pattern, in which the attacker and defender take actions to maximize their own interests.

[0037] Specifically include: The defender formulates the optimal defense resource allocation strategy in advance d , so that the expected value of the load loss of the power grid is as small as possible, and the corresponding upper layer defense model is established, which is expressed as: The optimization goal of the defense model is to minimize the load shedding of the power grid: (11), In the formula, Representing the resource allocation strategy of the grid defender, represents the set of all power nodes, ) is the node after the defense strategy and attack strategy are determined The load shearing amount at the location.

[0038] The defense resource constraints that need to be met are: (12), In the formula, Is the defender assigned to the line The number of defensive resources; is the total amount of defensive resources the defender has; Represents the set of all lines.

[0039] In this embodiment, the defense resources include reinforcement materials for improving the strength of the tower and additional visualization devices for strengthening the monitoring of the transmission channel.

[0040] The total amount of defense resources the defender has The calculation formula is: (13), In the formula, To improve the strength of the tower reinforcement material, To enhance the visualization of channel monitoring, and is the corresponding weight.

[0041] Among them, in order to convert different types of defense resources into a unified evaluation standard, normalization processing is required.

[0042] Normalized expression of reinforcement material resources: (14), In the formula, is the normalized reinforcement material resource, and the initial value of line deployment material is The total number of materials is , the minimum value is Generally set to 0.

[0043] The normalized expression of visualization device resources is: (15), In the formula, is the normalized visualization device resource, and the initial value of the line deployment device is The total number of devices is , the minimum value is Generally set to 0.

[0044] Step 4: Establish a mid-level attack model from the attacker's perspective based on the comprehensive importance of the line; A mid-level attack model from the attacker's perspective is established based on the comprehensive importance of the lines. Different types of attacks are normalized based on the attack strategy, the attack resources are quantitatively and comprehensively evaluated, and a simulation framework for the attack process under incomplete information conditions is constructed. Specifically include: Under incomplete information conditions, based on the difficulty of line attacks and line importance, the middle-level attack model that aims to maximize attack benefits is constructed as follows: (16), In the formula, Represents the attacker's attack resource allocation strategy; Is the defender assigned to the line The number of defensive resources; The defense resource strategy for the defender in the upper model; After comprehensive evaluation The importance of.

[0045] The attack resource constraints that need to be met are: (17), In the formula, is the attacker's assignment to the line The number of attack resources; A is the total amount of attack resources; Represents the set of all lines.

[0046] In this embodiment, the attack resources include drone resources used to destroy power transmission lines and graphite bombs that interfere with channel transmission.

[0047] Total attack resources A The calculation formula is: (18), In the formula, To destroy the transmission line drone resources, A graphite bomb to interfere with channel transmission. and is the corresponding weight.

[0048] In order to transform different types of defense resources into a unified evaluation standard, normalization is required.

[0049] Normalized expression of drone resources: (19), In the formula, is the normalized drone resource, and the initial value of the attack line drone is The total number of drones is , the minimum value is Generally set to 0.

[0050] The normalized expression of graphite bomb resources is: (20), In the formula, is the normalized graphite bomb resource, and the initial value of dropping the bomb is , the total number of bombs is , the minimum value is Generally set to 0.

[0051] Step 5: Establish a lower-level control model from the defender’s perspective based on the attack-defense game theory; Based on the attack-defense game theory, a lower-level control model from the defender's perspective is established, the line failure probability is calculated according to the line resource allocation, and a control process simulation framework under deliberate attack is constructed; The details include: The defender ensures the safe operation of the system by means of load shedding, with the goal of minimizing the actual load shedding amount. The established load shedding control model is: (twenty one), In the formula, f represents load shedding measures taken for defenders, represents the set of all power nodes, ) is a node The load shedding capacity.

[0052] The constraints include: (twenty two), (twenty three), (twenty four), (25), (26), (27), (28), In the formula, Representation Node The active and reactive power, For Node The load before the event, For Node After the event occurs, the load For Node i The voltage, For Node j The voltage, Representation Node i and j The conductance and susceptance between represents the set of all power nodes, Representation Node i and j The voltage angle difference between For Node The active power output of the generator is For Node The reactive power output of the generator, For Node The upper limit of the active power output of the generator, and For Node The upper and lower limits of the reactive power output of the generator, and Line The current and current limits of Indicates the operating status of the line. and Respectively represent nodes i Upper and lower voltage limits; The line operation status expression is as follows: (29), In the formula, Indicates the operating status of the line. 1 indicates a line fault and 0 indicates normal operation of the line.

[0053] Calculate line faults based on the obtained line defense and attack resource allocation strategies , and the Monte Carlo method is used to randomly sample fault lines and topology scenarios. The line fault probability calculation formula is: (30), In the formula, Indicates line l Fault; It is a line l Allocated attack resources, It is a line l allocated defense resources, C is the normalized probability constant, Represents the set of all lines.

[0054] Step 6: Based on the constructed upper-layer defense model, middle-layer attack model, and lower-layer control model, an optimization model under incomplete information conditions is constructed, and the optimal defense strategy is obtained by combining the determined defense strategy and attack resource upper limit; Based on the above three-layer optimization model, the IIDAD (information-based incomplete defender-attacker-defender) model framework under incomplete information conditions is constructed to determine the upper limits of defense resources and attack resources. The three-layer model is solved to obtain the optimal defense strategy and the minimum load shedding of the system. Based on the obtained optimal attack and defense strategy, the Monte Carlo method is used to simulate and generate operation scenarios. The specific steps include: First, we analyze the interactive process of the dynamic attack and defense game: We combine the resource digitization method of equation (15) and equation (20) to uniformly determine the total amount of defense resources and the total amount of attack resources.

[0055] The defender formulates a preliminary defense resource allocation strategy based on the upper-layer defense model in advance, and allocates a certain amount of defense resources to each line of the power grid to minimize the load shedding of the power grid; After the attacker detects and obtains the defender's defense strategy, he analyzes the comprehensive importance of the line under incomplete information conditions and combines the middle-level attack model to determine the attack strategy, aiming to maximize the attack benefit; After the defense strategy and attack strategy are determined, the defender executes the control strategy based on the lower-level control model and uses load shedding operations to redistribute the power flow so that the load loss of the power grid is as small as possible.

[0056] It can be seen that the relationship between the decision variables of the adjacent two-layer model is: The decision variables of the previous model determine the decision variables of the next model. The decision of the next model will be fed back to the previous model to affect the determination of the decision of the previous model. At the same time, the objective function of each model is correlated under the constraints of defense and attack strategies.

[0057] Based on the above process, the IIDAD model framework is constructed as follows: Figure 4 shown.

[0058] like Figure 5 As shown in the figure, the specific process of using the nested PSO algorithm to solve the three-layer optimization model is as follows: (1) Initialize the power grid model and set the total amount of defense resources The total amount of attack resources , initialize the particle swarm of the upper defense model and set related parameters. The number of iterations of the upper model is m ; (2) Calculate the optimization target of the defense model and generate the m Generation upper population , ; (3) Initialize the particle swarm of the middle-level attack model and set related parameters. The number of iterations of the middle-level model is n ; (4) Calculate the attack model optimization target and generate the n Intermediate population , ; (5) Calculate line faults based on the obtained line defense and attack resource allocation strategies , and the Monte Carlo method is used to randomly sample the fault lines and topological scenarios; (6) Initialize the particle swarm of the lower-level control model and set related parameters. The number of iterations of the lower-level model is t , calculate the load shedding amount of the system under this topology scenario; (7) Feed the obtained load shedding period back to the upper model in step 2, update the defender’s defense resource allocation strategy, and perform the next round of iterative optimization; (8) If the maximum number of iterations is not reached, the population speed and position are updated, the fitness is calculated and the global optimal solution is adjusted. If the maximum number of iterations is reached, the optimal defense allocation strategy and the minimum load shedding amount of the system under this strategy are output.

[0059] Analyze the operation scenario generation process: In the process of solving the three-layer optimization model with the nested PSO algorithm, the defense resource allocation strategy and attack resource allocation strategy of the line are obtained, and the failure probability of the line is further calculated; Based on the failure probability of the line, Monte Carlo sampling is used to generate faulty lines. Combined with the topological scenarios, the corresponding load shedding amount in each topological scenario is calculated, thereby generating the operation scenario of the power cyber-physical system under deliberate attacks.

[0060] In view of the problem that traditional defense models do not adequately consider cyber-physical interaction behaviors, this paper considers physical attacks on power transmission networks and their communication networks, and constructs the defense resource allocation problem of power cyber-physical systems into a three-layer optimization model of defense-attack-defense regulation with the goal of minimizing load shedding. The proposed method can effectively provide the system with the optimal defense resource allocation plan and operation scenario under physical attack scenarios, and improve the system's ability to resist the impact of deliberate attack events.

[0061] Embodiment 2 This embodiment provides a system for generating operation scenarios of a power cyber-physical system under deliberate attacks, including: A topology building module is used to build a topology model of the power information-physical system based on the topology information obtained in the power grid diagram database; A line comprehensive importance calculation module is used to calculate the line weighted betweenness in combination with the power information-physical system topology model, and calculate the line comprehensive importance based on the line weighted betweenness and line attributes; The defense model building module is used to quantify defense resources based on the attack and defense game theory, and to build an upper-level defense model under deliberate attacks in combination with a defense resource allocation strategy that minimizes the expected value of load loss in the power grid; The attack model building module is used to combine the comprehensive importance of the lines, quantify the attack resources, and build a mid-level attack model of the attack process under incomplete information conditions; The control model building module is used to calculate the line failure probability according to the line resource allocation based on the attack and defense game theory, and to build the lower-level control model under deliberate attack; The operation scenario generation module is used to solve the optimal attack and defense resource allocation strategy of the line based on the upper-level defense model, the middle-level attack model and the lower-level control model; calculate the failure probability of the line based on the optimal attack and defense resource allocation strategy of the line, and generate the operation scenario of the power information-physical system under intentional attack based on the failure probability of the line.

[0062] It should be noted that the specific implementation method of generating the operation scenario of the power information-physical system under intentional attack in the second embodiment of the present invention is similar to the specific implementation method of the method for generating the operation scenario of the power information-physical system under intentional attack in the first embodiment of the present invention. Please refer to the description of the method part for details. In order to reduce redundancy, it will not be repeated here.

[0063] Embodiment 3 This embodiment provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps in the method for generating an operation scenario of an electric power information-physical system under a deliberate attack as described above.

[0064] Embodiment 4 This embodiment provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the steps in the method for generating an operation scenario of an electric power information-physical system under a deliberate attack as described above are implemented.

[0065] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for generating operation scenarios of power cyber-physical systems under deliberate attacks, characterized in that: The steps include: Based on the topological information obtained in the power grid diagram database, a topological model of the power cyber-physical system is constructed; Combined with the topological model of the power cyber-physical system, the line weighted betweenness is calculated, and the comprehensive importance of the line is calculated based on the line weighted betweenness and line attributes; Based on the attack and defense game theory, the defense resources are quantified, and the upper-layer defense model under intentional attacks is constructed by combining the defense resource allocation strategy that minimizes the expected value of load loss in the power grid. Combined with the comprehensive importance of the lines, the attack resources are quantified, and a mid-level attack model of the attack process under incomplete information conditions is constructed; Based on the attack and defense game theory, the line failure probability is calculated according to the line resource allocation, and the lower-level control model under deliberate attack is constructed; Based on the upper-layer defense model, the middle-layer attack model and the lower-layer control model, the optimal attack and defense resource allocation strategy of the line is solved; The failure probability of the line is calculated based on the optimal attack and defense resource allocation strategy of the line, and the operation scenario of the power cyber-physical system under intentional attack is generated based on the failure probability of the line.

2. The method for generating an operation scenario of an electric power cyber-physical system under a deliberate attack according to claim 1, characterized in that: The calculation process of line weighted betweenness includes the calculation of communication line weighted betweenness and physical line weighted betweenness. The specific calculation process includes: Calculate the weight of the communication line or the weight of the physical line; Calculating a weighted shortest path length based on a weight of a communication line or a weight of a physical line; The weight of the communication line or the weighted betweenness of the physical line is calculated based on the weighted shortest path.

3. The method for generating an operation scenario of an electric power cyber-physical system under a deliberate attack according to claim 1, characterized in that: The formula for the comprehensive importance of the line is: ， ， ， In the formula, For Line The weighted betweenness of the communication line, For Line The weighted betweenness of the physical line, For Node s and t The total number of weighted shortest paths between For Node s and t Passing lines l The number of weighted shortest paths, V is the total number of nodes, is the weight parameter of the autonomously defined communication network, corresponding to is the weight parameter of the physical network.

4. The method for generating an operation scenario of an electric power cyber-physical system under a deliberate attack according to claim 1, characterized in that: The upper layer defense model under deliberate attack is: The optimization goal is to minimize the load shedding of the power grid: ， The defense resource constraints that need to be met are: ， ， ， ， in, Representing the resource allocation strategy of the grid defender, represents the set of all power nodes, ) is the node after the defense strategy and attack strategy are determined The load shear at Is the defender assigned to the line The number of defensive resources; is the total amount of defensive resources the defender has; Represents the set of all lines. To improve the strength of the tower reinforcement material, To enhance the visualization of channel monitoring, and is the corresponding weight, and the initial value of the line deployment material is The total number of materials is , the minimum value is , the initial value of the line deployment device is The total number of devices is , the minimum value is .

5. The method for generating an operation scenario of an electric power cyber-physical system under a deliberate attack according to claim 1, characterized in that: The middle-level attack model of the attack process under incomplete information conditions is: The goal is to maximize the attack benefit: ， The attack resource constraints that need to be met are: ， ， ， ， in, Represents the attacker's attack resource allocation strategy; Is the defender assigned to the line The number of defensive resources; The defense resource strategy for the defender in the upper model; After comprehensive evaluation The importance of is assigned to the line by the attacker The number of attack resources; A is the total amount of attack resources; Represents the set of all lines. To destroy the transmission line drone resources, A graphite bomb to interfere with channel transmission. and is the corresponding weight, and the initial value of the attack line drone is The total number of drones is , the minimum value is , the initial value of dropping bombs is , the total number of bombs is , the minimum value is .

6. The method for generating an operation scenario of an electric power cyber-physical system under a deliberate attack according to claim 1, characterized in that: The lower-level control model under deliberate attack is: The actual load shedding amount is minimized: ， The constraints include: ， ， ， ， ， ， ， in, f represents load shedding measures taken for defenders, represents the set of all power nodes, ) is a node The load shedding capacity, Representation Node The active and reactive power, For Node The load before the event, For Node After the event occurs, the load For Node i The voltage, For Node j The voltage, Representation Node i and j The conductance and susceptance between Representation Node i and j The voltage angle difference between For Node The active power output of the generator is For Node The reactive power output of the generator, For Node The upper limit of the active power output of the generator, and For Node The upper and lower limits of the reactive power output of the generator, and Line The current and current limits of Indicates the operating status of the line. and Respectively represent nodes i The upper and lower voltage limits.

7. The method for generating an operation scenario of an electric power cyber-physical system under a deliberate attack according to claim 1, characterized in that: Based on the upper-layer defense model, the middle-layer attack model and the lower-layer control model, the optimal attack and defense resource allocation strategy for the line is solved, including: Determine the total amount of defense resources and the total amount of attack resources; Formulate a preliminary defense resource allocation strategy based on the upper-layer defense model, and allocate a certain amount of defense resources to each line of the power grid to minimize the load shedding of the power grid; After obtaining the defender's defense strategy, the comprehensive importance of the line is analyzed based on incomplete information conditions, and the attack strategy is determined in combination with the middle-level attack model, with the goal of maximizing the attack benefit; After the defense strategy and attack strategy are determined, the defender executes the control strategy based on the lower-level control model and uses load shedding operations to redistribute the power flow so that the load loss of the power grid is as small as possible.

8. A system for generating operation scenarios of power cyber-physical systems under deliberate attacks, characterized in that: include: A topology building module is used to build a topology model of the power information-physical system based on the topology information obtained in the power grid diagram database; A line comprehensive importance calculation module is used to calculate the line weighted betweenness in combination with the power information-physical system topology model, and calculate the line comprehensive importance based on the line weighted betweenness and line attributes; The defense model building module is used to quantify defense resources based on the attack and defense game theory, and to build an upper-level defense model under deliberate attacks in combination with a defense resource allocation strategy that minimizes the expected value of load loss in the power grid; The attack model building module is used to combine the comprehensive importance of the lines, quantify the attack resources, and build a mid-level attack model of the attack process under incomplete information conditions; The control model building module is used to calculate the line failure probability according to the line resource allocation based on the attack and defense game theory, and to build the lower-level control model under deliberate attack; Run the scenario generation module to solve the optimal attack and defense resource allocation strategy for the line based on the upper-layer defense model, the middle-layer attack model, and the lower-layer control model; The failure probability of the line is calculated based on the optimal attack and defense resource allocation strategy of the line, and the operation scenario of the power cyber-physical system under intentional attack is generated based on the failure probability of the line.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps in the method for generating an operation scenario of an electric power information-physical system under a deliberate attack as described in any one of claims 1 to 7 are implemented.

10. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the steps in the method for generating an operation scenario of an electric power information-physical system under a deliberate attack as described in any one of claims 1 to 7 are implemented.

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