Direct-current micro-grid distributed elastic control system

Abstract

The invention discloses a direct-current micro-grid distributed elastic control system which comprises a plurality of power supply nodes, and each power supply node is in wired and / or wireless communication with a neighbor power supply node in a communication network. Each power supply node comprises a cooperative controller consisting of a primary controller and a secondary controller; the secondary controller comprises a communication link attack compensator; the secondary controller is used for generating a voltage reference signal according to the power supply node, a state signal of a neighbor power supply node in the communication network and a communication link attack compensation signal; the primary controller outputs a control signal to the current converter controller according to the voltage reference signal and a measurement signal of the current output by the current converter of the power supply node where the primary controller is located; and the converter controller is used for converting the control signal into a PWM signal and sending the PWM signal to the converter so as to control the bus voltage. The DC micro-grid distributed elastic control system can completely recover the control targets of DC micro-grid voltage regulation and accurate power distribution under the attack of an unknown communication link.

Description

Technical Field

[0001] The present invention relates to the technical field of direct current microgrid control, and in particular to a distributed elastic control system for a direct current microgrid. Background Art

[0002] A DC microgrid is a microgrid with DC characteristics. It effectively integrates distributed renewable energy generation devices, energy storage equipment and DC loads to achieve local consumption of green energy, thereby improving energy efficiency. Distributed power supply nodes are integrated into the DC microgrid using converters as access devices to reasonably control the output of each distributed power supply, that is, its output voltage and current. The converter-oriented DC microgrid distributed control system is a key device to ensure the stable and normal operation of the DC microgrid.

[0003] The droop control method is the most common decentralized collaborative control method, which can achieve collaborative work between distributed power sources when there is no communication between power nodes and the transmission line impedance can be ignored. However, when the transmission line impedance between power sources in the microgrid cannot be ignored, the accuracy of power allocation achieved by only using the droop control method will be reduced.

[0004] The secondary cooperative controller based on the consistency algorithm is used to compensate for the droop control method, which effectively overcomes the influence of the transmission line on the power distribution. However, when the secondary controller currently used is attacked by the network, the transmitted information is deliberately tampered with by the attack signal, and further penetrates into the entire microgrid through the communication link, resulting in uncontrolled power distribution, and the purpose of coordinated control to achieve voltage regulation and power distribution cannot be achieved. Summary of the invention

[0005] Aiming at the problem of uncontrolled power distribution under the above communication link attack, a distributed elastic control system for DC microgrid is proposed. The system can alleviate the impact of unknown attack signals under the communication link attack and achieve the control goal of restoring microgrid power distribution and voltage regulation.

[0006] In order to solve the above technical problems, a technical solution adopted by the present application is: to provide a DC microgrid distributed elastic control system, characterized in that the system comprises: a plurality of power supply nodes, each of the power supply nodes respectively performing wired communication and / or wireless communication with neighboring power supply nodes in a communication network;

[0007] Each of the power supply nodes includes a collaborative controller consisting of a primary controller and a secondary controller; the secondary controller includes a communication link attack compensator;

[0008] The secondary controller is used to generate a voltage reference signal according to a communication link attack compensation signal of a communication link attack compensator, a state signal of the secondary controller of the power supply node and a neighboring power supply node in the communication network;

[0009] The primary controller is used to output a control signal to the converter controller according to the measurement signal of the converter output current of the power supply node and the voltage reference signal; the converter controller is used to convert the control signal into a PWM signal and send it to the converter, and the converter is used to control the bus voltage according to the PWM signal;

[0010] The communication link attack compensator is configured to determine a communication link attack compensation signal according to the following expression:

[0011]

[0012] in, A communication link attack compensation signal representing power node i; represents the compensation signal gain of power node i. When power node i is attacked by the communication link, otherwise, t represents the time factor, dt represents the microvariable with the time factor as the variable; γ represents the constant factor, γ>0; e i An error signal representing the state of power node i.

[0013] In one embodiment, the primary controller is configured to determine the control signal of the converter controller according to the following expression:

[0014]

[0015] Among them, u i represents the control signal of the converter controller of the power supply node i; ni I represents the voltage reference signal of the input power node i, the voltage reference signal comes from the output of the secondary controller; ti a measurement signal representing an output current of the converter at a power supply node i; is the droop coefficient, and the value of the droop coefficient is set according to the following formula:

[0016]

[0017] Among them, α is a positive constant, Represents the output current rating of the power supply node i.

[0018] In one embodiment, the secondary controller comprises:

[0019] A state error observer, used for generating the state error signal of the power supply node according to the state variables of the power supply node and neighboring power supply nodes in the communication network;

[0020] The communication link attack compensator is used to generate the communication link attack compensation signal according to whether the communication link of the power supply node is attacked by an error data injection attack and the state error signal of the power supply node;

[0021] a state error corrector, configured to generate a state error correction signal of the power supply node according to the state error signal output by the state error observer and the communication link attack compensation signal output by the communication link attack compensator;

[0022] A voltage regulator, used for generating a voltage regulation signal according to the rated operating voltage of the DC microgrid and the voltage measurement signal output by the converter of the power supply node;

[0023] A reference voltage generator, configured to generate the voltage reference signal of the power supply node according to the state error correction signal output by the state error corrector and the voltage adjustment signal output by the voltage regulator

[0024] In one embodiment, the state error observer is configured to determine the state error signal between the power supply node and the neighboring power supply nodes in the communication network according to the following expression:

[0025]

[0026] Among them, e i represents the state error signal of the power supply node i; φ i and φ j are the state variables of power node i and power node j respectively; ij is the communication line gain from power node j to power node i. If there is a state variable φ from power node j to power node i j transmission, then a ij >0, otherwise a ij =0.

[0027] In one of the embodiments, at the same time, the communication link of only one of the power supply nodes is directly attacked by the erroneous data injection attack, and the rest of the power supply nodes are all subject to chain interference due to the state variable transmission of the attacked power supply node.

[0028] In one embodiment, the state error corrector is configured to determine the state error correction signal according to the following expression:

[0029]

[0030] in, The state error correction signal representing the power supply node i; i a state error signal representing the power supply node i; Represents the communication link attack compensation signal of power node i.

[0031] In one embodiment, the voltage regulator is configured to determine the voltage regulation signal according to the following expression:

[0032] Δv i =g i (v rat -v i )

[0033] Where Δv i represents the voltage regulation signal of the power supply node i; v rat represents the rated operating voltage of the DC microgrid; v i represents the bus voltage measurement signal corresponding to power node i; g i represents the gain of the voltage regulation signal of the power node i, when the power node i is allowed to access the rated working voltage, g i >0, otherwise, g i =0.

[0034] In one of the embodiments, the reference voltage generator is configured to determine the voltage reference signal according to the following expression:

[0035]

[0036] Among them, v ni represents the voltage reference signal of the power supply node i; v rat represents the rated operating voltage of the DC microgrid; Δv i A voltage regulation signal representing a power supply node i; and a are the state error correction signals of power node i and power node j respectively; ij is the communication line gain from power node j to power node i. If there is a state error correction signal from power node j to power node i transmission, then a ij >0, otherwise a ij =0; n is a non-negative integer.

[0037] In one embodiment, under the error data injection attack, the communication link of the DC microgrid controls all power nodes through the primary controller and the secondary controller of each power node to simultaneously restore the voltage regulation function and the precise current distribution function, that is,

[0038]

[0039] Among them, v i , i∈{1,2,...,n} represents the bus voltage measurement signal corresponding to power node i; v rat Represents the rated operating voltage of the DC microgrid;

[0040]

[0041] Among them, I ti , i∈{1,2,...,n} represents the measurement signal of the output current of the converter at the power supply node i; i∈{1,2,...,n} represents the output current rating of power node i.

[0042] In one of the embodiments, the communication mode between neighboring power supply nodes in the communication network adopts full-duplex mode and / or simplex mode.

[0043] However, when the secondary controller currently in use is attacked by a network, the transmitted information is deliberately tampered with by the attack signal and further penetrates into the entire microgrid through the communication link, resulting in uncontrolled power distribution and the inability to achieve the purpose of coordinated control to realize voltage regulation and power distribution.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] 1. The present invention adopts a fully distributed collaborative control solution, so that the scale of the system is not limited and supports hot plugging of power supply nodes.

[0046] 2. The present invention achieves the control goal of restoring voltage regulation and power distribution under unknown communication link attacks by improving the secondary controller.

[0047] 3. The DC microgrid distributed elastic control system involved in the embodiment of the present invention includes a communication link attack compensation item. By adjusting the local attack compensation item, the accurate power distribution and voltage regulation of multiple distributed power sources in the DC microgrid can be restored simultaneously.

[0048] 4. The embodiments of the present invention do not involve prior knowledge of communication link attack signals, and cover the chain interference suffered by neighboring power nodes due to the state variable transmission of the attacked power node, so that the elastic collaborative controller is more in line with actual application requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 A schematic diagram of distributed collaborative control of a DC microgrid according to an embodiment of the present invention, wherein the communication network is interfered by a network attack;

[0050] Figure 2 is a schematic diagram of a DC microgrid according to an embodiment of the present invention, wherein the communication network is interfered by a network attack;

[0051] Figure 3 A block diagram of a distributed elastic control system of a DC microgrid and a schematic diagram of its connection method according to an embodiment of the present invention;

[0052] Figure 4 A schematic diagram of a DC microgrid voltage and current distributed elastic control system according to an embodiment of the present invention;

[0053] Figure 5 FIG. 4 is a schematic diagram of tracking error of an attack compensation item for an unknown attack signal according to an embodiment of the present invention. DETAILED DESCRIPTION

[0054] The following is a further and clearer description of the embodiments of the present invention in conjunction with the accompanying drawings. It should be noted that the use of the controller involved in the present invention is not limited to this embodiment. The controller involved in the present invention is applicable to different DC microgrid structures and should be included in the protection scope of the present invention accordingly.

[0055] like Figure 1 As shown, Figure 1 The schematic diagram of distributed collaborative control of a DC microgrid according to an embodiment of the present invention is shown, wherein the communication network is interfered by network attacks. The DC microgrid electrical network may include multiple DC buses, and the electrical network topology and load type are not limited, and are applicable to the DC microgrid distributed elastic control system described in the present invention. The DC microgrid distributed elastic control system shown in the present invention includes multiple power supply nodes.

[0056] The distributed power source in the microgrid is represented in the figure as a cascade structure of battery elements, converters and output filters. In actual implementation, the power supply node may be various distributed new energy devices, such as wind power equipment, photovoltaic equipment, energy storage units and other devices that can output electrical energy. Among them, according to the actual output needs, the converter can be a DC-DC converter, AC-DC converter, etc. It should be noted that the devices that the power supply node should have, such as the local controller contained in the distributed power supply, are not shown in the figure. Figure 1 Draw it specifically in.

[0057] The coordinated controller of each distributed power source may include a primary controller and a secondary controller. The input signals of the primary controller may include two signals, namely, a voltage reference signal output by the secondary controller and a converter output current measurement signal from the power node. The output of the primary controller, as the command signal of the local controller, will directly control the output voltage of the converter of the power node.

[0058] The secondary controller is used to generate a voltage reference signal according to the status signals of the secondary controllers of the power node where it is located and its neighboring power nodes in the communication network.

[0059] The primary controller is used to output a control signal to the converter controller based on the measurement signal of the converter output current and the voltage reference signal of the power node where it is located; the converter controller is used to convert the control signal into a PWM signal and send it to the converter, and the converter is used to control the bus voltage according to the PWM signal.

[0060] The input signals of the secondary controller include the state information of the neighboring power node transmitted through the communication network and the measurement signal of the converter output voltage of the power node. The input of the primary controller includes the voltage reference signal output by the secondary controller and the measurement signal of the converter output current of the power node.

[0061] In the specific implementation process, Figure 1 The communication network shown in the figure can be connected by wired communication and / or wireless communication. The neighboring power nodes can use a full-duplex mode or a simplex mode communication mode. In the communication network, it is not necessary to establish a connection between any two power nodes. It only needs the communication network topology to be a strongly connected and balanced graph.

[0062] Among them, strong connectivity and balanced graph belong to the concepts in graph theory. A strongly connected graph means that there is a directed communication path from any power node to the rest of the power nodes. A balanced graph means that any power node has limited input communication lines and output communication lines, and the number of its input communication lines and output communication lines is equal.

[0063] like Figure 2 As shown, Figure 2 Schematic diagram of a DC microgrid according to an embodiment of the present invention, wherein the communication network is disturbed by a network attack. Figure 2 It includes 6 power supply nodes and 6 loads. It should be noted that the scope of application of the present invention is not limited to this embodiment. This embodiment includes a DC microgrid with any number of power supply loads and any topology structure, which is applicable to the present invention. In addition, Figure 2Only the electrical network topology of the physical layer and the communication network topology of the communication layer are represented. The upper-level controllers of the control layer, such as the primary controller and the secondary controller, are not clearly indicated in each distributed power source, which should be included in the implementation process.

[0064] Figure 2 The communication network topology shown in the figure is a ring connection. In the actual implementation process, the communication network topology is not limited to the ring connection mode. As long as the coordinated controllers of the distributed power sources are connected through a duplex communication network based on an undirected graph, the communication network needs to be connected, that is, there is a communication path between any two power nodes. If the communication network topology is connected through a simplex communication network based on a directed graph, the communication network should be strongly connected and balanced.

[0065] like Figure 3 As shown, Figure 3 The block diagram of the distributed elastic control system of a DC microgrid according to an embodiment of the present invention and a schematic diagram of its connection method. In this embodiment, the DC microgrid includes a physical layer, a communication layer and a control layer. The primary control of the coordinated controller of the distributed power source is implemented by droop control.

[0066] The control law of droop control in this embodiment is as follows:

[0067]

[0068] Among them, u i represents the control signal of the converter controller of the power supply node i; the voltage reference signal v ni is the output of the secondary controller in the power node i. The input signal of the secondary controller may include the bus voltage measurement v of the local power node i and the state variables φ of the neighboring power nodes j . Voltage reference signal v ni Transmitted to the local power node through the communication network.

[0069] The droop coefficient is set according to the following formula:

[0070]

[0071] Among them, α is a positive constant, Represents the output current rating of the power supply node i.

[0072] like Figure 4 As shown, Figure 4 The schematic diagram of a DC microgrid voltage and current distributed elastic control system according to an embodiment of the present invention is shown in FIG. In this embodiment, the secondary controller may include five parts, namely, a state error observer, a communication link attack compensator, a state error corrector, a voltage regulator, and a reference voltage generator.

[0073] The state error corrector is used to generate a state error correction signal of the power node where the state error corrector is located according to the state error signal output by the state error observer and the communication link attack compensation signal output by the communication link attack compensator. The state error observer can observe the weighted sum of the state errors of the power node where it is located and the neighboring power nodes, and the weight coefficient a ij is the communication line gain from neighbor power node j to power node i, when the communication connection exists, a ij >0, otherwise a ij =0.

[0074] The communication link attack compensator is used to generate a communication link attack compensation signal according to whether the communication link of the power node where it is located is attacked by error data injection and the state error signal of the power node where it is located.

[0075] The state error corrector is used to generate a state error correction signal of the power supply node according to the state error signal output by the state error observer and the communication link attack compensation signal output by the communication link attack compensator.

[0076] The voltage regulator is used to generate a voltage regulation signal according to the rated operating voltage of the DC microgrid and the voltage measurement signal output by the converter of the power supply node where it is located.

[0077] The reference voltage generator is used for generating a voltage reference signal of a power supply node according to a state error correction signal output by the state error corrector and a voltage adjustment signal output by the voltage regulator.

[0078] In this embodiment, the secondary controller of the power node includes five parts, namely, a state error observer, a communication link attack compensator, a state error corrector, a voltage regulator, and a reference voltage generator, so as to achieve the control goal of restoring voltage regulation and accurate power distribution under unknown communication link attacks. In addition, the distributed elastic control system includes a communication link attack compensation item, which can simultaneously restore accurate power distribution and voltage regulation of multiple distributed power sources in the DC microgrid by adjusting the local attack compensation item.

[0079] In one embodiment, at the same time, the communication link of only one power node is directly attacked by the injection of erroneous data, and the rest of the power nodes are all affected by the chain interference caused by the transmission of the state variables of the attacked power node. In this embodiment, the DC microgrid distributed elastic control system provided by the present application can meet the control requirements when the communication link of only one power node is directly attacked by the injection of erroneous data, and the precise power distribution and voltage regulation of multiple distributed power sources in the DC microgrid can be restored at the same time by adjusting the local attack compensation item, so that the elastic collaborative controller is more in line with the actual application requirements, and the stability and availability of the DC microgrid distributed elastic control system can be improved.

[0080] In one embodiment, the state error observer is configured to determine the state error signal between the local power node and the neighboring power node in the communication network according to the following expression:

[0081]

[0082] Among them, e i Represents the state error signal of power node i; φ i and φ j are the state variables of power node i and power node j respectively; a ij is the communication line gain from power node j to power node i. If there is a state variable φ from power node j to power node i j transmission, then a ij >0, otherwise a ij =0.

[0083] In this embodiment, the state error corrector can use the communication link attack compensation signal to correct the observed state error, thereby providing a more accurate state error signal, so that the DC microgrid voltage and current distributed elastic control system has more stable and excellent performance.

[0084] In one embodiment, the state error corrector is configured to determine the state error correction signal according to the following expression:

[0085]

[0086] in, represents the state error correction signal of power node i; e i represents the state error signal of power supply node i; represents the communication link attack compensation signal of power node i.

[0087] In this embodiment, the communication link attack compensation signal of the power node i is added to correct the state error signal to obtain a state error correction signal, and correction is performed for the situation of unknown communication link attack, so that the voltage reference signal generated by the reference voltage generator is more accurate, and voltage regulation of multiple distributed power sources in the DC microgrid can be achieved.

[0088] The communication link attack compensator can use local data to elastically compensate for all unknown communication link attacks on the power node i, and does not need to accurately extract the parameters of the network attack signal of the error data injection attack, as shown in the following formula:

[0089]

[0090] in, represents the communication link attack compensation signal of power node i; represents the compensation signal gain. When the power node i is attacked by the communication link, otherwise, t represents the time factor, dt represents the microvariable with the time factor as the variable; γ represents the constant factor, γ>0; e i An error signal representing the state of power node i.

[0091] Compared with the prior art, the embodiment of the present application adopts a fully distributed collaborative control solution, so that the scale of the system is not limited and can support hot plugging of power nodes. The secondary controller of the power node is also improved, so that the control goal of fully restoring voltage regulation and power distribution can be achieved under unknown communication link attacks. At the same time, the distributed elastic control system involved in the embodiment of the present invention includes a communication link attack compensation item. By adjusting the local attack compensation item, the accurate power distribution and voltage regulation of multiple distributed power sources in the DC microgrid can be restored at the same time. In addition, the embodiment of the present application does not involve prior knowledge of communication link attack signals, and can cover the chain interference suffered by neighboring power nodes due to the transmission of state variables of the attacked power node, so that the elastic collaborative controller is more in line with the application requirements during actual implementation.

[0092] In one embodiment, the reference voltage generator generates a reference voltage signal for the primary controller, which is obtained by summing and integrating the outputs of the state error observer and the voltage regulator, as shown in the following equation:

[0093]

[0094] Among them, v ni Represents the voltage reference signal of power node i; v rat Indicates the rated operating voltage of the DC microgrid; Δv i represents a voltage regulation signal of a power supply node i; and are the state error correction signals of power node i and power node j respectively; a ij is the communication line gain from power node j to power node i. If there is a state error correction signal from power node j to power node i transmission, then a ij >0, otherwise a ij =0; t represents the time factor, dt represents the microvariable with the time factor as the variable; n is a non-negative integer.

[0095] It is worth noting that the integrators involved in this application can be replaced by a PID controller (Proportion Integration Differentiation). The proportional integral controller consists of a proportional unit (P), an integral unit (I) and a differential unit (D), and is controlled by the three parameters Kp, Ki and Kd. The PID controller can be applied to systems that are basically linear and whose dynamic characteristics do not change over time. The PID controller compares the collected data with a reference value, and then uses the difference to calculate a new input value. The purpose of this new input value is to allow the system data to reach or remain at the reference value. The input value can be adjusted based on historical data and the occurrence rate of the difference, which can make the system more accurate and more stable.

[0096] In one embodiment, when the communication link of the DC microgrid is attacked by an error data injection, the primary controller and the secondary controller of each power node will control all power nodes to simultaneously restore the voltage regulation function and the precise current distribution function, that is,

[0097]

[0098] Among them, v i , i∈{1,2,...,n} represents the bus voltage measurement signal corresponding to power node i; v rat Indicates the rated operating voltage of the DC microgrid;

[0099]

[0100] Among them, I ti , i∈{1,2,...,n} represents the measurement signal of the converter output current at the power node i; i∈{1,2,…,n} represents the output current rating of power node i.

[0101] In one embodiment, the voltage regulator is used to achieve a weighted value of the difference between the local bus voltage and the rated voltage, and the weighting coefficient g i For voltage regulation signal gain, when power node i allows access to the rated operating voltage, gi >0, otherwise, g i =0.

[0102] The voltage regulator may be configured to determine the voltage regulation signal according to the following expression:

[0103] Δv i =g i (v rat -v i )

[0104] Where Δv i represents the voltage regulation signal of power node i; v rat Indicates the rated working voltage of the DC microgrid; v i represents the bus voltage measurement signal corresponding to power node i; g i represents the gain of the voltage regulation signal, when the power node i allows access to the rated operating voltage, g i >0, otherwise, g i =0.

[0105] In this embodiment, the voltage regulator can output a corresponding voltage regulation signal based on the rated operating voltage of the DC microgrid, the bus voltage measurement signal corresponding to the power node i, and the gain of the voltage regulation signal, thereby realizing automatic adjustment of the output voltages of multiple distributed power sources in the DC microgrid and improving the stability of the distributed elastic control system of the DC microgrid.

[0106] like Figure 5 As shown, Figure 5 FIG. 1 is a schematic diagram of tracking error of an attack compensation item for an unknown attack signal according to an embodiment of the present invention. The schematic diagram of tracking error of an attack compensation item for an unknown attack signal shown in this embodiment can be used to Figure 2 When all communication links of the power node 6 are attacked by unknown error data injection, the entire shaded area in the figure can be regarded as the communication data being interfered by the network attack. In order to show the effect of the attack compensation item tracking the unknown attack signal, the equivalent amplitude of all communication link attack signals received by the power node 6 can be manually analyzed.

[0107] like Figure 5 As shown in the unknown attack signal curve, Figure 5 The tracking error signal curve converges to 0 at 8 seconds and remains stable, which means that the attack compensation item provided by the present invention can track the unknown attack signal in real time. The DC microgrid system in this embodiment can fully restore the control objectives of voltage regulation and power distribution under the attack of unknown communication link.

Claims

1. A DC microgrid distributed elastic control system, characterized in that: The system comprises: a plurality of power supply nodes, each of which performs wired communication and / or wireless communication with a neighboring power supply node in a communication network; Each of the power supply nodes includes a collaborative controller consisting of a primary controller and a secondary controller; the secondary controller includes a communication link attack compensator; The secondary controller is used to generate a voltage reference signal according to a communication link attack compensation signal of a communication link attack compensator, and state signals of the secondary controllers of the power supply node and its neighboring power supply nodes in the communication network; The primary controller is used to output a control signal to the converter controller according to the measurement signal of the converter output current of the power node and the voltage reference signal; the converter controller is used to convert the control signal into a PWM signal and send it to the converter, and the converter is used to control the bus voltage according to the PWM signal; The communication link attack compensator is configured to determine the communication link attack compensation signal according to the following expression: in, A communication link attack compensation signal representing power node i; represents the compensation signal gain of power node i. When power node i is attacked by the communication link, otherwise, t represents the time factor, dt represents the microvariable with the time factor as the variable; γ represents the constant factor, γ>0; e i An error signal representing the state of power node i.

2. The DC microgrid distributed elastic control system according to claim 1, characterized in that: The primary controller is configured to determine the control signal of the converter controller according to the following expression: Among them, u i represents the control signal of the converter controller of the power supply node i; ni I represents the voltage reference signal of the input power node i, the voltage reference signal comes from the output of the secondary controller; ti a measurement signal representing an output current of the converter at a power supply node i; is the droop coefficient, and the value of the droop coefficient is set according to the following formula: Among them, α is a positive constant, Represents the output current rating of the power supply node i.

3. The DC microgrid distributed elastic control system according to claim 1, characterized in that: The secondary controller comprises: A state error observer, used for generating the state error signal of the power supply node according to the state variables of the power supply node and neighboring power supply nodes in the communication network; The communication link attack compensator is used to generate the communication link attack compensation signal according to whether the communication link of the power supply node is attacked by an error data injection attack and the state error signal of the power supply node; A state error corrector, configured to generate a state error correction signal of the power supply node according to the state error signal output by the state error observer and the communication link attack compensation signal output by the communication link attack compensator; A voltage regulator, used for generating a voltage regulation signal according to the rated operating voltage of the DC microgrid and the voltage measurement signal output by the converter of the power supply node; The reference voltage generator is used to generate the voltage reference signal of the power supply node according to the state error correction signal output by the state error corrector and the voltage adjustment signal output by the voltage regulator.

4. The DC microgrid distributed elastic control system according to claim 3, characterized in that: The state error observer is configured to determine the state error signal between the power supply node and the neighboring power supply nodes in the communication network according to the following expression: Among them, e i represents the state error signal of the power supply node i; φ i and φ j are the state variables of power node i and power node j respectively; ij is the communication line gain from power node j to power node i. If there is a state variable φ from power node j to power node i j transmission, then a ij >0, otherwise a ij =0.

5. The DC microgrid distributed elastic control system according to claim 3, characterized in that: At the same time, the communication link of only one of the power supply nodes is directly attacked by the erroneous data injection, and the rest of the power supply nodes are all subjected to chain interference due to the state variable transmission of the attacked power supply node.

6. The DC microgrid distributed elastic control system according to claim 3, characterized in that: The state error corrector is configured to determine the state error correction signal according to the following expression: in, The state error correction signal representing the power supply node i; i a state error signal representing the power supply node i; Represents the communication link attack compensation signal of power node i.

7. The DC microgrid distributed elastic control system according to claim 3, characterized in that: The voltage regulator is configured to determine the voltage regulation signal according to the following expression: Δv i =g i (v rat -v i ) Where Δv i represents the voltage regulation signal of the power supply node i; v rat represents the rated operating voltage of the DC microgrid; v i represents the bus voltage measurement signal corresponding to power node i; g i represents the gain of the voltage regulation signal of the power node i, when the power node i is allowed to access the rated working voltage, g i >0, otherwise, g i =0.

8. The DC microgrid distributed elastic control system according to claim 3, characterized in that: The reference voltage generator is configured to determine the voltage reference signal according to the following expression: Among them, v ni represents the voltage reference signal of the power supply node i; v rat represents the rated operating voltage of the DC microgrid; Δv i A voltage regulation signal representing a power supply node i; and a are the state error correction signals of power node i and power node j respectively; ij is the communication line gain from power node j to power node i. If there is a state error correction signal from power node j to power node i transmission, then a ij >0, otherwise a ij =0; n is a non-negative integer.

9. The DC microgrid distributed elastic control system according to claim 8, characterized in that: Under the error data injection attack, the communication link of the DC microgrid will control all power nodes through the primary controller and the secondary controller of each power node to simultaneously restore the voltage regulation function and the precise current distribution function, that is, Among them, v i , i∈{1,2,...,n} represents the bus voltage measurement signal corresponding to power node i; v rat Represents the rated operating voltage of the DC microgrid; Among them, I ti , i∈{1,2,...,n} represents the measurement signal of the output current of the converter at the power supply node i; Represents the output current rating of the power supply node i.

10. The DC microgrid distributed elastic control system according to claim 1, characterized in that: The communication mode between neighboring power supply nodes in the communication network adopts full-duplex mode and / or simplex mode.

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