A distributed elastic control method for information security of microgrids in a space-ground integrated network

Abstract

The present invention discloses a distributed elastic control method for information security of a microgrid in a space-ground integrated network, comprising the following steps: establishing a control model of a distributed microgrid, determining the locations where DoS attacks and random noises occur; establishing DoS attack and random noise models according to the characteristics of the space-ground integrated network; establishing an observer model with adjustable parameters; setting the adjustable parameters, introducing a non-singular matrix, determining according to the adjustable parameters, and further introducing a symmetric positive definite matrix and a matrix, solving the observer gain based on the requirements of system robustness; constructing a controller based on the control model of the distributed microgrid and the DoS attack and random noise model, obtaining state observation values ​​and attack observation values ​​according to the observer model obtained after the solution, and constructing an elastic control signal to perform compensation control on the microgrid.

Description

Technical Field

[0001] The present invention relates to the field of microgrid information security technology, and in particular to a distributed elastic control method for microgrid information security in a space-ground integrated network. Background Art

[0002] Microgrids can be regarded as small power systems that support self-generation and self-use of electricity and local consumption. They are suitable for areas that are difficult for large power grids to reach, such as islands and remote areas, to ensure power supply in local areas. Microgrids are mainly distributed power sources, which can be adjusted using energy storage systems and control devices to meet load requirements. Since the primary control of microgrids is differential control, secondary control is required. The secondary control strategies are mainly centralized control and distributed control. Compared with centralized control, distributed control has higher advantages in efficiency, scalability, reliability and flexibility. Unlike the primary control method, secondary control requires the support of a reliable communication network.

[0003] Traditional ground communication networks have limited coverage in harsh environments, while the integrated ground-ground network has become one of the representative technologies in the 6G network era due to its wide coverage, low transmission delay and high flexibility. Although the integrated ground-ground network has many advantages, its broadcast, susceptibility to atmospheric interference, and open characteristics are vulnerable to network attacks and noise. These factors have brought challenges to the control of microgrids and may greatly reduce the control stability of the entire system. In the worst case, the system state performance may continue to deteriorate, and eventually fail to converge, resulting in system collapse.

[0004] Denial-of-Service (DoS) is a malicious network attack method. Attackers use various methods to prevent the target system or network resources from providing normal services to legitimate users. In microgrids, DoS attacks mainly interrupt power transmission by blocking and delaying communications, resulting in data / information unavailability; at the same time, random noise is inevitably introduced in the integrated space-ground network. At present, most of the research focuses on the impact of a single factor of DoS attack or noise on microgrids, and there are few control strategies that consider the impact of these two factors at the same time, making it difficult to ensure the stable operation of microgrids. Summary of the invention

[0005] In view of this, the present invention provides a distributed elastic control method for microgrid information security in a space-ground integrated network, which is used to at least solve the problem that the microgrid control method in the prior art is difficult to simultaneously eliminate network attacks and noise interference.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] A distributed elastic control method for information security of a microgrid in a space-ground integrated network comprises the following steps:

[0008] Establish a control model for distributed microgrids to determine where DoS attacks and random noise occur;

[0009] According to the characteristics of the space-ground integrated network, a DoS attack and random noise model is established;

[0010] According to the microgrid control model, DoS attack and random noise model, considering the stable operation and control of the microgrid, an observer model with adjustable parameters is established, including error estimation Expressions and observer equations;

[0011] Setting adjustable parameters and introducing non-singular matrices ,in, , is the identity matrix, is the Laplace matrix, is a circulant matrix, is the gain of the adjustable parameter, is the adjustable parameter matrix, is the state transition matrix between input and output, determined by adjustable parameters , and further introduce the symmetric positive definite matrix With the matrix , based on the system robustness requirement, solve the observer gain ;

[0012] A controller is constructed based on the control model of the distributed microgrid and the DoS attack and random noise model. The state observation values ​​and attack observation values ​​are obtained according to the observer model obtained after solution. The state observation values ​​and attack observation values ​​are obtained to construct elastic control signals for compensation control of the microgrid.

[0013] Preferably, each distributed power source in the microgrid is abstracted as an inverter, and the control model of the distributed microgrid includes primary control and secondary control:

[0014] One-time control:

[0015] ;

[0016] In the formula, For the The output voltage of the inverter is is the rated voltage, For the The preset droop coefficient of each inverter, For the The output current of each inverter;

[0017] Secondary Control:

[0018] ;

[0019] ;

[0020] ;

[0021] ;

[0022] ;

[0023] ;

[0024] In the formula, For the secondary control The output voltage of the inverter is is the secondary control compensation term, Represents the global average voltage value, For the Inverter The output current at the moment, For the The preset droop coefficient of each inverter, For the Inverter The output current at the moment, Indicates the rated power distribution value, is the number of inverters, For any inverter, is the communication compensation voltage, Representative and Is there a communication relationship between the inverters? Take 1 if there is none, take 0 if there is none. To contain the gain, Assign values ​​to electricity, and Respectively and The output current of each inverter is and Respectively and The rated current of each inverter, That is, the secondary control quantity, , and They are the gain values ​​of secondary control, communication compensation voltage, and power distribution value respectively.

[0025] Preferably, the specific contents of establishing the DoS attack and random noise model include:

[0026] DoS Attack:

[0027] ;

[0028] ;

[0029] In the formula, Representatives in The number of DoS attacks in the time interval; Representatives in The total duration of all DoS attacks in the time interval, ;

[0030] Random Noise:

[0031] ;

[0032] ;

[0033] ;

[0034] In the formula, and are the current and voltage measurements affected by noise, and are the noise components affecting current and voltage respectively, For the Inverter The output current at the moment, for and The total amount of noise, represents the state variable after noise injection, Represents the state variables of the system.

[0035] Preferably, the specific contents of establishing an observer model with adjustable parameters include:

[0036] Constructing error estimates expression:

[0037] ;

[0038] In the formula, is the Laplace matrix Elements of Representative and Is there a communication relationship between the inverters? Take 1 if there is none, take 0 if there is none. Indicates The observer output value of each inverter is, Indicates The actual output value of the system, For the circulant matrix The element of represents the containment gain;

[0039] The observer equation is:

[0040] ;

[0041] In the formula, is the differential value of the system state estimate, represents the state control matrix, is the estimated value of the system state, is the total control variable of the system, is the differential value of the error estimate.

[0042] Preferably, the specific contents of solving the observer gain include:

[0043] According to the observer equation, the global dynamic error is obtained :

[0044] ;

[0045] In the formula, is the differential value of the system state estimate, represents the differential value of the system state, Indicates the disturbance caused by DoS attack to the system. is the error estimate, is the differential value of the error estimate; Represents the estimated value of the system state The state variables of the system difference;

[0046] The error estimate Substituting the expression into the above formula, we get:

[0047] ;

[0048] ;

[0049] In the formula, represents tensor product; Indicates The global dynamic error of the observer is represents the global dynamic error of all observers in the whole system, is the identity matrix;

[0050] make , sorted out:

[0051] ;

[0052] Setting H infinity control method Performance level and the stability circle of the control ;

[0053] For non-singular matrices If there exists a symmetric positive definite matrix and a matrix If the following conditions are met, the observer gain :

[0054] ;

[0055] ;

[0056] ;

[0057] ;

[0058] In the formula, is the radius of the circular area, is the center of the circular area.

[0059] Preferably, the state control matrix The calculation method is:

[0060] ;

[0061] in represents a column vector whose elements are all 1, For the The preset droop coefficient of each inverter, is the total equivalent load impedance.

[0062] Preferably, the specific contents of obtaining the state observation value and the attack observation value to construct a flexible control signal to perform compensation control on the microgrid include:

[0063] The controller model is obtained according to the control model of the distributed microgrid:

[0064] ;

[0065] ;

[0066] ;

[0067] ;

[0068] In the formula, represents the state variables of the system, Represents the global average voltage value, is the rated voltage, For the The preset droop coefficient of each inverter, For the Inverter The output current at the moment, Indicates the rated power distribution value, To add the state variables after noise and DoS attack, Indicates the impact caused by DoS attack. , and are gain values, is the communication compensation voltage, Assign values ​​to electricity, Indicates noise interference, is the estimated value of the system state, is the state control matrix, is the total control variable of the system, is the observer gain, is the error estimate, is the differential value of the error estimate, is the compensation amount of the control, which is compensated to the secondary control middle.

[0069] Preferably, it also includes:

[0070] for The solution of , and the Lyapunov function are used to verify the stability of the system in this case, which includes the following contents:

[0071] If the state control matrix Belong to is the center of the circle, For the radius circle, and if and only if there exists a symmetric positive definite matrix satisfy:

[0072] ;

[0073] For a non-singular matrix and the symmetric positive definite matrix , Also for a symmetric positive definite matrix, construct the Lyapunov function:

[0074] ;

[0075] If the symmetric positive definite matrix and The circular area satisfies:

[0076] ;

[0077] And multiply the above formula by the matrix , and finally the system gain at the current observer is obtained Can satisfy Performance level and stable in a circular area .

[0078] It can be seen from the above technical solutions that, compared with the prior art, the present invention discloses a method for distributed elastic control of microgrid information security in a space-ground integrated network, which has the following beneficial effects:

[0079] The advantages of the present invention are mainly reflected in the following aspects: First, compared with the existing control methods, the present invention realizes accurate real-time tracking of random noise by designing a distributed elastic observer, showing accurate following performance. It is particularly worth emphasizing that the present invention breaks through the requirements of traditional observers for the derivability of noise and can effectively handle non-derivable random noise. This innovation makes the state of the controlled object more diverse and flexible, significantly expands the scope of application of the observer, and can cope with more complex working conditions and problems. Secondly, even under complex and strong random noise interference, the distributed elastic control method based on the observer can still achieve efficient distribution of voltage and current, ensure stable operation of the power grid, and greatly improve the robustness and anti-interference ability of the system. It fully meets the stringent operation requirements of microgrids under the integrated space-ground network. BRIEF DESCRIPTION OF THE DRAWINGS

[0080] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 work.

[0081] Figure 1 A flow chart of a distributed elastic control method for information security of a microgrid in a space-ground integrated network provided by the present invention;

[0082] Figure 2 A schematic diagram of a system subjected to DoS attack and noise interference provided by an embodiment of the present invention; Figure 2 (a) DoS attack and noise impact on uplink; Figure 2 (b) shows the normal and shielded terminals under the influence of DoS attack and noise on the uplink; Figure 2 (c) DoS attack and noise impact on the downlink; Figure 2(d) shows the normal and shielded terminals under the influence of DoS attack and noise in the downlink;

[0083] Figure 3 This is a control block diagram corresponding to a distributed elastic control method for microgrid information security in a space-ground integrated network provided by the present invention.

[0084] Figure 4 This is a schematic diagram of the observer random noise following;

[0085] Figure 5 Schematic diagram of the original voltage with noise added to the microgrid;

[0086] Figure 6 Schematic diagram of the original current with noise added to the microgrid;

[0087] Figure 7 Schematic diagram of voltage control of microgrid under the influence of noise;

[0088] Figure 8 Schematic diagram of the current controlled by the microgrid under the influence of noise. DETAILED DESCRIPTION

[0089] 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.

[0090] Due to factors such as terrain and funding, ground networks do not cover remote areas sufficiently, so microgrids in remote areas rely on integrated sky-ground communication networks. However, the openness and broadcasting characteristics of the integrated sky-ground network are susceptible to network attacks and noise interference, which not only brings challenges to the control of microgrids, but also threatens the stable operation of microgrids. The present invention discloses a distributed elastic control method for microgrid information security in a sky-ground integrated network to deal with DoS attacks and noise problems in a sky-ground integrated network. The specific flow chart is as follows: Figure 1 shown.

[0091] Establish a control model for distributed microgrids to determine where DoS attacks and random noise occur;

[0092] Inverter: First, the distributed power source is abstracted as an inverter, the inverter is modeled, and the number of inverters in the model is defined. , and at the same time determine whether there is communication between the inverters and the communication method, subscript Representative A power supply.

[0093] The control of distributed power sources mainly includes primary control and secondary control. The primary control adopts the droop control method, which consists of a voltage and current double closed loop. Since droop control is a differential control, secondary control is also required in the distributed microgrid to eliminate the voltage error. Based on the distributed consistency theory, the distributed power sources in the microgrid can be abstracted into multiple intelligent agents. Each intelligent agent only communicates with its neighbors, and uses its own and neighbor information for calculation and estimation, without the need for a central controller; using sparse communication networks, the shortcomings of centralized control are avoided, and distributed power sources can be plug-and-play.

[0094] In order to make the output voltage of each inverter the same as the set voltage value, that is, , so the primary control adopts droop control, satisfying the following formula:

[0095] (1.1)

[0096] is the output voltage of the inverter, To set the voltage value, is the set droop coefficient, is the rated voltage, is the output current.

[0097] The goal of secondary control is to ensure global average voltage recovery and accurate power distribution. From equation 1.1, it can be deduced that satisfying equations 1.3 and 1.4 can meet the secondary control goal. Represents the global average voltage value, Indicates the rated voltage, In order to achieve the secondary control target, a compensation term is added to the original droop control equation 1.1. , where the secondary control The expression of is shown in equation 1.2. Here, the pinning consistency algorithm is used for design, and the auxiliary controller is designed as shown in 1.5 and 1.6. Equations 1.5 and 1.6 are derived from equations 1.3 and 1.4 respectively, that is, through and The communication compensation voltage and power distribution value between intelligent agents. To contain the gain, For intelligent agents , The weights between them can be obtained according to the communication mode between multiple agents. , If , If there is a communication connection between , otherwise it is 0. Combining equations 1.6 and 1.7, we get equation 1.7, which is the total value of secondary control, where , , These are the gain values ​​for secondary control, communication compensation voltage, and power distribution value. These gain values ​​are controlled by proportional control. They are added to reduce the error in control, and then the error is eliminated by integral control. The gain value is generally selected according to the control effect. ,in represents a column vector whose elements are all 1, To summarize the equivalent load impedance, substituting it into 1.2 gives .

[0098] (1.2)

[0099] (1.3)

[0100] (1.4)

[0101] (1.5)

[0102] (1.6)

[0103] (1.7)

[0104] According to the characteristics of the space-ground integrated network, a DoS attack and random noise model is established;

[0105] DoS attack: DoS attack is a very common attack method in microgrids. It usually occurs in the communication link. By interfering with the communication between the inverters in the microgrid, the information obtained by the secondary control is biased, thereby making the system unstable. In order to ensure the stable operation of the microgrid under attack, the attack time of the DoS attack described here is not infinite, that is, it is a bounded attack.

[0106] Combined with Figure 2 Explain how the uplink and downlink are affected by DoS attacks and noise interference, and what impact the interference and attacks will have on the network; Figure 3 This is a control block diagram corresponding to the control strategy of the present invention.

[0107] in The attack frequency satisfies formula 1.8, where Representatives in The duration of the attack satisfies equation 1.9, where Representatives in The total duration of all attacks in the time interval, Equations 1.8 and 1.9 indicate that DoS attacks are bounded.

[0108] (1.8)

[0109] (1.9)

[0110] In this embodiment, the total duration of the attack is 10, the number of attacks is 3, and the duration is 3 times different, namely 1, 2, and 3.

[0111] Random noise: Due to the openness and broadcasting of the integrated space-ground network and weather factors such as clouds, fog and rain, noise will be injected into the microgrid during transmission. Both current and voltage measurements will be affected by noise. The noise signal here is a random signal and does not need to be conductive.

[0112] and are the current and voltage measurements affected by noise, and are the noise components affecting current and voltage respectively, For the Inverter The output current at the moment. Under the influence of noise, the control output becomes equation 1.12, where for and The total amount of noise, represents the state variable after noise injection, Represents the state variable of the system. Since the protection device can easily detect when there are large fluctuations in current and voltage, the is bounded, there exists a non-negative satisfy .

[0113] (1.10)

[0114] (1.11)

[0115] (1.12)

[0116] According to the microgrid control model, DoS attack and random noise model, considering the stable operation and control of the microgrid, an observer model with adjustable parameters is established, including error estimation Expression and observer equation; build a controller based on the control model of the distributed microgrid and the DoS attack and random noise model, obtain the state observation value and attack observation value according to the solved observer model, and build a flexible control signal to compensate and control the microgrid:

[0117] Observer model establishment: Different from the centralized control method, the distributed control method needs to use the information difference between different nodes to form the error estimation , as shown in Equation 1.13, where represents the output value of the designed observer, Represents the actual output value of the system, the Laplace matrix The elements in If the composition , If there is a communication connection between , otherwise 0. For the circulant matrix G elements of which To contain the gain.

[0118] (1.13)

[0119] The observer model is shown in Equation 1.14, is the estimated value of the system state, is the actual state value of the system, is the differential value of the system state estimate, is the differential value of the error estimate. Where H is the observer gain, which needs to be designed. is an adjustable parameter, the purpose of which is to improve the ability to estimate attacks, thereby making the observer more stable and flexible. is the gain of the adjustable parameter, which is set to 2.0 in this embodiment. is the adjustable parameter matrix.

[0120] (1.14)

[0121] In the design process of the observer, it is necessary to first determine the matrix ,in is the identity matrix, , They are the Laplace matrices With the circulant matrix elements of which This is a diagram of the connections between multiple inverters. The nodes discussed here are and There is a directed graph between them. is the state transition matrix between input and output, is the adjustable parameter matrix of the observer. Represents the tensor product. For adaptive adjustable parameters, mainly To set up the matrix, first Set to a full row rank matrix, The settings will Performance cause an impact The value of is smaller. Then the parameter Adjust and select to get smaller , thus making the system performance better.

[0122] Controller model establishment: According to the establishment of the inverter in the above microgrid model, is the state variable of the system, as shown in 1.15, is the total control variable of the system, which satisfies the following formula 1.16 and mainly consists of two parts: The expression of is shown in 1.17, which can be derived from equations 1.7 and 1.12. Based on equation 1.7, the noise input is added, that is, , The design is derived from equation 1.14 as shown in 1.18.

[0123] (1.15)

[0124] (1.16)

[0125] (1.17)

[0126] (1.18)

[0127] Observer gain design: According to the above observer state equation, the observer gain Need to be based on the following formula The value of is obtained. At the same time, the design of the observer needs to consider the stability and convergence of the system. Therefore, the PP gain and right To solve.

[0128] According to the above formula 1.14, the global dynamic error can be obtained As shown in the following equation 1.19, substituting equation 1.13 into equation 1.19 can obtain the expression of global dynamic error, is the differential value of the system state estimate, is the state differential value of the system.

[0129] It is represented by 1.20, Represents the disturbance caused by DoS attack to the system. According to the vector form combined with 1.19, we can get the form of formula 1.22, where Represents the tensor product. The following will be used to perform stability analysis based on this form and design the control matrix based on the PP gain. The value of .

[0130] (1.19)

[0131] (1.20)

[0132] (1.21)

[0133] Rearranging 1.21 yields the following formula 1.22, , is a non-singular matrix.

[0134] (1.22)

[0135] Then set Performance level and the stability circle of the control ,in Infinite control is achieved by designing a controller feedback gain , so that the closed-loop system is stable; for non-singular matrices If there exists a symmetric positive definite matrix and a matrix Satisfies equations 1.23 and 1.24, where equations 1.25 and 1.26 respectively express Therefore, the observer gain Here, Obtained through LMIs.

[0136] (1.23)

[0137] (1.24)

[0138] (1.25)

[0139] (1.26)

[0140] For adjustable parameter observer The solution of , using Lyapunov function to prove the stability of the system in this case, includes:

[0141] Lemma 1: Given a matrix Belong to is the center of the circle, For the radius circle, and if and only if there exists a symmetric positive definite matrix Satisfies the following equation 1.27:

[0142] (1.27)

[0143] For a non-singular matrix and the symmetric positive definite matrix , It is also a symmetric positive definite matrix. By constructing the Lyapunov function of equation 1.28, it can be proved that the dynamic error equation satisfies Performance, that is According to Lemma 1.27, we can get that for a symmetric positive definite matrix and The circular area satisfies equation 1.29, and the matrix 1.30 is multiplied on the left and right, and finally the system can satisfy Performance level and stable in a circular area .

[0144] (1.28)

[0145] (1.29)

[0146] (1.30)

[0147] The present invention will be further described below through specific experiments:

[0148] This experiment was simulated and the method was verified in the simulink module of MATLAB software. The experimental results are shown in Figure 4-8 As shown, Figure 4 This is a schematic diagram of the random noise following of the observer, where the original noise uses the white noise module in Simulink with an amplitude of 5. As can be seen from the diagram, the curve representing the following of the observer to the random non-differentiable noise can achieve a good following effect on the random non-differentiable white noise after 3 seconds, and the two lines overlap, indicating that both the following effect and the response speed are good.

[0149] Figure 5 Schematic diagram of the original voltage with noise added to the microgrid. Figure 6 Schematic diagram of the original current with noise added to the microgrid, Figure 5 and Figure 6 The figure is a schematic diagram of the voltage and current under the influence of noise without control. By adding random non-conductive noise interference to the original control, four curves WM1-WM4 can be obtained, of which WM1-WM3 are the curves of the three units, and WM4 is the reference curve. Under noise interference, the four voltage curves have large fluctuations and have deviated from the rated voltage of 48V. The current cannot be distributed according to the impedance. The system cannot operate normally.

[0150] Figure 7 Schematic diagram of voltage control of microgrid under the influence of noise, Figure 8 Schematic diagram of the current controlled by the microgrid under the influence of noise, where: Figure 7 and Figure 8 The schematic diagram of the three units after adding control and the reference value, where WM1-WM3 are the curves of the three units, and WM4 is the reference curve. Figure 7 and Figure 8 and Figure 5 , Figure 6 By comparison, it can be seen that after adding control, the voltage can be restored to the rated voltage of 48V. Although there is a slight fluctuation, it is normal, and the current can be distributed according to impedance. The control effect is good, and the system can be restored to normal operation.

[0151] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A distributed elastic control method for information security of microgrids in a space-ground integrated network, characterized in that: The following steps are involved: Establish a control model for distributed microgrids to determine where DoS attacks and random noise occur; According to the characteristics of the space-ground integrated network, a DoS attack and random noise model is established; According to the microgrid control model, DoS attack and random noise model, considering the stable operation and control of the microgrid, an observer model with adjustable parameters is established, including error estimation Expressions and observer equations; Setting adjustable parameters and introducing non-singular matrices ,in, , is the identity matrix, is the Laplace matrix, is a circulant matrix, is the gain of the adjustable parameter, is the adjustable parameter matrix, is the state transition matrix between input and output, determined by adjustable parameters , and further introduce the symmetric positive definite matrix With the matrix , based on the system robustness requirement, solve the observer gain ; A controller is built based on the control model of the distributed microgrid and the DoS attack and random noise model. The state observation value and the attack observation value are obtained according to the observer model obtained after the solution. The state observation value and the attack observation value are obtained to construct a flexible control signal to compensate and control the microgrid. The specific contents of establishing an observer model with adjustable parameters include: Constructing error estimates expression: ， In the formula, is the Laplace matrix Elements of Representative and Is there a communication relationship between the inverters? Take 1 if there is none, take 0 if there is none. Indicates The observer output value of each inverter is, Indicates The actual output value of the system, is the circulant matrix The element of represents the containment gain; The observer equation is: ， In the formula, is the differential value of the system state estimate, represents the state control matrix, is the estimated value of the system state, is the total control variable of the system, is the differential value of the error estimate; The specific contents of solving the observer gain include: According to the observer equation, the global dynamic error is obtained : ， In the formula, is the differential value of the system state estimate, represents the differential value of the system state, Indicates the disturbance caused by DoS attack to the system. is the error estimate, is the differential value of the error estimate; Represents the estimated value of the system state The state variables of the system difference; The error estimate Substituting the expression into the above formula, we get: ， ， In the formula, represents tensor product; Indicates The global dynamic error of the observer is represents the global dynamic error of all observers in the whole system, is the identity matrix; make , sorted out: ， Setting H infinity control method Performance level and the stability circle of the control ; For non-singular matrices For example, if there exists a symmetric positive definite matrix P and a matrix Y that satisfy the following conditions, then the observer gain : ， ， ， ， In the formula, is the radius of the circular area, is the center of the circular area.

2. According to the method of distributed elastic control of microgrid information security in a space-ground integrated network according to claim 1, it is characterized in that: Each distributed power source in the microgrid is abstracted as an inverter, and the control model of the distributed microgrid includes primary control and secondary control: One-time control: ， In the formula, For the The output voltage of the inverter is is the rated voltage, For the The preset droop coefficient of each inverter, For the The output current of each inverter; Secondary Control: ， ， ， ， ， ， In the formula, For the secondary control The output voltage of the inverter is is the secondary control compensation term, Represents the global average voltage value, For the Inverter The output current at the moment, For the The preset droop coefficient of each inverter, For the Inverter The output current at the moment, Indicates the rated power distribution value, is the number of inverters, For any inverter, is the communication compensation voltage, Representative and Is there a communication relationship between the inverters? Take 1 if there is none, take 0 if there is none. To contain the gain, Assign values ​​to electricity, and Respectively and The output current of each inverter is and Respectively and The rated current of each inverter, That is, the secondary control quantity, and They are the gain values ​​of secondary control, communication compensation voltage, and power distribution value respectively.

3. According to the method of distributed elastic control of microgrid information security in a space-ground integrated network of claim 1, it is characterized in that: The specific contents of establishing DoS attack and random noise model include: DoS Attack: ， ， In the formula, Representatives in The number of DoS attacks in the time interval; Representatives in The total duration of all DoS attacks in the time interval, ; Random Noise: ， ， ， In the formula, and are the current and voltage measurements affected by noise, and are the noise components affecting current and voltage respectively, For the Inverter The output current at the moment, for and The total amount of noise, represents the state variable after noise injection, Represents the state variables of the system.

4. According to the method of distributed elastic control of microgrid information security in a space-ground integrated network according to claim 1, it is characterized in that: State Control Matrix A The calculation method is: ， in represents a column vector whose elements are all 1, For the The preset droop coefficient of each inverter, is the total equivalent load impedance.

5. According to the method of distributed elastic control of microgrid information security in a space-ground integrated network of claim 1, it is characterized in that: The specific contents of obtaining state observation values ​​and attack observation values ​​to construct elastic control signals for compensating control of microgrids include: The controller model is obtained according to the control model of the distributed microgrid: ， ， ， ， In the formula, represents the state variables of the system, Represents the global average voltage value, is the rated voltage, For the The preset droop coefficient of each inverter, For the Inverter The output current at the moment, Indicates the rated power distribution value, To add the state variables after noise and DoS attack, Indicates the impact caused by DoS attack. and are gain values, is the communication compensation voltage, Assign values ​​to electricity, Indicates noise interference, is the estimated value of the system state, is the state control matrix, is the total control variable of the system, is the observer gain, is the error estimate, is the differential value of the error estimate, is the compensation amount of the control, which is compensated to the secondary control middle.

6. The method for distributed elastic control of microgrid information security in a space-ground integrated network according to claim 1 is characterized in that: Also includes: for H The solution of , and the Lyapunov function are used to verify the stability of the system in this case, which includes the following contents: If the state control matrix Belong to ( a , 0 ) is the center of the circle, For the radius circle, and if and only if there exists a symmetric positive definite matrix satisfy: ， For a non-singular matrix and the symmetric positive definite matrix , Also for a symmetric positive definite matrix, construct the Lyapunov function: ， If the symmetric positive definite matrix and The circular area satisfies: ， And multiply the above formula by the matrix , and finally the system gain at the current observer is obtained Can satisfy Performance level and stable in a circular area .

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