A distributed elastic secondary control system for islanded AC microgrids

Abstract

The present invention discloses a distributed elastic secondary control system for an islanded AC microgrid, relating to the technical field of power system control. The system comprises the following components: an extended state observer module, an FDI attack model research module, an attack signal estimation and compensation module, and a elastic distributed secondary control module. By introducing the extended state observer and the attack signal estimation and compensation module, the present invention can accurately estimate and compensate for the impact of FDI attacks on system frequency and voltage. When the system is attacked by FDI, it can quickly adjust the control strategy, stabilize the frequency and voltage, and prevent the system from collapsing or becoming unstable. At the same time, through the improved distributed secondary control strategy, optimal active power sharing is achieved, further improving the stability and security of the system.

Description

Technical Field

[0001] The present invention relates to the technical field of power system control, and in particular to a distributed elastic secondary control system for an islanded AC microgrid. Background Art

[0002] With the rapid development of distributed generation (DG) technology, island AC microgrids are playing an increasingly important role in power systems. Island AC microgrids are microgrid systems that can maintain independent operation and provide power to loads when the main grid is out of power or fails. However, as microgrids expand in size and complexity, their stability and security issues are becoming increasingly prominent. In particular, when facing false data injection (FDI) attacks, the stable operation of microgrids faces severe challenges.

[0003] FDI attacks are malicious network attacks against power systems. Attackers attempt to interfere with or disrupt the normal operation of the system by tampering with or forging sensor data and control instructions. In isolated AC microgrids, FDI attacks may target the actuators (such as inverters, controllers, etc.) or communication links of distributed generators, causing key parameters such as system frequency and voltage to deviate from normal values, seriously affecting the stability and security of the microgrid.

[0004] Traditional microgrid control strategies often have obvious shortcomings when facing FDI attacks. On the one hand, these strategies usually rely on additional interactive information or communication networks to monitor and control the status of the microgrid, which increases the complexity and potential vulnerability of the system. Once the communication network is attacked or fails, the control effect of the entire microgrid will be greatly reduced. On the other hand, traditional control strategies often lack sufficient flexibility and adaptability when dealing with FDI attacks, making it difficult to accurately estimate and compensate for the impact of the attack on the system in real time, resulting in instability of system frequency and voltage, and imbalance in active power distribution. Summary of the Invention

[0005] The purpose of the present invention is to overcome the shortcomings of the existing technology and provide a distributed resilient secondary control system for an islanded AC microgrid. It can accurately estimate the impact of FDI attacks on system frequency and voltage by introducing an extended state observer in each distributed generator (DG). At the same time, an improved distributed secondary control strategy is adopted to achieve precise control of frequency and voltage through specific control formulas. Parameters such as the incremental cost of active power and control input are considered in the control process to achieve optimal active power sharing. In addition, the present invention also studies two main FDI attack models, including FDI attacks on local actuators and FDI attacks on communication links, and designs an attack signal estimation and compensation module to compensate for the impact of attacks on the system.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: a distributed elastic secondary control system for an islanded AC microgrid, the system comprising the following components: an extended state observer module, an FDI attack model research module, an attack signal estimation and compensation module, and a elastic distributed secondary control module;

[0007] The extended state observer module is set in each distributed generator DG to estimate the impact of FDI attacks on system frequency and voltage;

[0008] The FDI attack model research module is used to study two FDI attack models, including FDI attacks on local actuators and FDI attacks on communication links, and define the impact of FDI attacks on frequency and voltage;

[0009] The attack signal estimation and compensation module uses an extended state observer to estimate the impact of the attack signal and compensates for the attack impact by adjusting frequency and voltage control;

[0010] The elastic distributed secondary control module combines the output of the extended state observer to accurately control the frequency and voltage of the DG through droop control and secondary control. The control strategy adjusts the control input to compensate for the system deviation caused by the FDI attack. The specific control formula is: i =ω r -kη i (P i )+u iw , v i =v r -n i Q i +u iv , where ω i and v i Represent the frequency and voltage of the i-th distributed generator DG, P i and Q i are the active power and reactive power of the i-th DG, η i (P i ) represents the incremental cost function of active power, u iw and u iv It is the control input item used to compensate for the deviation of frequency and voltage, k and n i are control coefficients, used to adjust the rate of change of frequency and voltage, ω r and v rare the rated frequency and voltage of the system, respectively. When FDI attack exists, the impact of FDI attack on system frequency and voltage is estimated by extending the state observer module. According to the above estimation results, the distributed secondary control strategy is adjusted to restore the frequency and voltage to the reference value and achieve the optimal active power sharing, that is, the active power incremental cost η between each DG i (P i ) is consistent, where the dynamic behaviors of frequency and voltage control under FDI attack are obtained, and the frequency control term u for frequency control is generated by the extended state observer. iw and the voltage control term u for voltage control iv , in order to achieve the above goals, the control input u iw and u iv Calculated using the following integral formula: Among them, ω ij represents the frequency difference term, η ij represents the incremental cost difference term, v ij represents the voltage difference term, a ij It is the adjacency matrix element of the communication network, indicating whether there is a communication connection between the two DGs i and j. i Is to indicate whether i DG receives the reference value; k wi 、k pi and k vi It is the control coefficient, which is used to adjust the rate of change of frequency and voltage. By adjusting the frequency and voltage control inputs, it can achieve coordinated control among various distributed generators without a central controller.

[0011] Furthermore, the extended state observer module estimates the impact of the attack signal on the system frequency and voltage, thereby compensating for the impact, ensuring that the system frequency and voltage can be restored to the reference value and achieving optimal active power sharing. The algorithm formula for estimating the impact of the attack signal on the system frequency and voltage is: Where, Δ wi and Δ vi Represent the influence of frequency and voltage attack signals respectively, and is the observed frequency and voltage attack signal, ω i and v i are the actual frequency and voltage of the i-th distributed generator DG, ω i and v i are the estimated frequency and voltage, u wi and u vi These are the control inputs for frequency and voltage respectively.

[0012] Furthermore, the FDI attack model research module is used to study two FDI attack models, including FDI attacks on local actuators and FDI attacks on communication links, and define the impact of FDI attacks on frequency and voltage. For FDI attacks on local actuators, the attack signal is injected into the control signal, changing the secondary control data. The attack model is: Among them, u iw and u iv are the control inputs for frequency and voltage, ω ij and v ij Represent the frequency and voltage differences, k wi 、k pi and k vi is the control coefficient, δ i is an attack indicator. When i DGs are attacked, δ i =1, otherwise δ i =0, and It's an attack signal.

[0013] Furthermore, the FDI attack model research module is used to study two FDI attack models, including FDI attacks on local actuators and FDI attacks on communication links, and define the impact of FDI attacks on frequency and voltage. For FDI attacks on communication links, the attack signal is injected into the communication data between DGs, changing the information received from neighboring DGs. The attack model is:

[0014] Among them, ω i and v i denote the frequency and voltage of the i-th distributed generator (DG), η i is the incremental cost, and It is the frequency and voltage information after being attacked. is the incremental cost after being attacked.

[0015] Furthermore, the FDI attack model research module is used to study two FDI attack models, including FDI attacks on local actuators and FDI attacks on communication links. For FDI attacks on communication links, and It is the frequency and voltage information after being attacked. is the incremental cost after being attacked, defined as: Among them, δ ij is an attack indicator. When the communication link i and j is attacked, δ ij =1, otherwise δij =0,a j ω 、a j

[0016] η and The two attack models demonstrate how FDI attacks interfere with frequency and voltage control by injecting false data, thereby undermining system stability. Specifically, they manifest as follows: Frequency and voltage deviation: The attack signal causes the frequency and voltage to deviate from their reference values, undermining system stability; Power sharing failure: Due to the interference of the attack signal, the optimal sharing of active power and reactive power cannot be achieved.

[0017] Furthermore, the attack signal estimation and compensation module uses an extended state observer to estimate the impact of the attack signal and compensates for the attack impact by adjusting the frequency and voltage control. The calculation formula for adjusting the frequency and voltage is: Among them, Δ wi and Δ vi It's the actual attack signal. and is the attack signal estimated by the extended state observer.

[0018] Furthermore, the dynamic behavior of the frequency and voltage control of the resilient distributed secondary control module under FDI attack is analyzed by the extended state observer to generate the frequency control term u for frequency control. iw and the voltage control term u for voltage control iv During the process, ij represents the frequency difference term, defined as η ij represents the incremental cost difference term, which is defined as: v ij represents the voltage difference term, which is defined as: where ω ij represents the frequency difference between the i-th distributed generator and the j-th distributed generator, v ij represents the voltage difference between the i-th distributed generator and the j-th distributed generator, η ij represents the incremental cost difference between the i-th distributed generator and the j-th distributed generator.

[0019] Furthermore, the elastic distributed secondary control module needs to achieve frequency and voltage synchronization during the process of adjusting the frequency and voltage control inputs, and the algorithm formula used is: Among them, ω i represents the frequency of the i-th distributed generator, w ref Indicates the system reference frequency, vi represents the voltage of the i-th distributed generator, v ref Indicates the system reference voltage, η i is the incremental cost of active power of the voltage of the i-th distributed generator, η j is the incremental cost of active power of the jth distributed generator.

[0020] Compared with the existing technology, this distributed elastic secondary control system for isolated AC microgrid has the following beneficial effects:

[0021] First, by introducing an extended state observer and an attack signal estimation and compensation module, the present invention can accurately estimate and compensate for the impact of FDI attacks on system frequency and voltage. This allows the system to quickly adjust its control strategy when subjected to FDI attacks, stabilize frequency and voltage, and prevent system collapse or instability. Furthermore, through an improved distributed secondary control strategy, optimal active power sharing is achieved, further improving system stability and security.

[0022] Second, by introducing an extended state observer module, the present invention can accurately estimate the impact of FDI attacks on the system frequency and voltage in the isolated AC microgrid, enabling the system to promptly identify and compensate for the attack signal when it is attacked by FDI, thereby maintaining the stability and security of the system.

[0023] Other advantages, objects and features of the present invention will be described in part in the following description and, in part, will be apparent to those skilled in the art based on an examination of the following or may be learned from the practice of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0025] Figure 1 Schematic diagram of a distributed elastic secondary control system for an islanded AC microgrid;

[0026] Figure 2 A schematic diagram of a distributed resilient secondary control system for an islanded AC microgrid when the actuators and communication links are attacked by FDI;

[0027] Figure 3 Schematic diagram of a distributed elastic secondary control system control scheme for islanded AC microgrids. DETAILED DESCRIPTION

[0028] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0029] A distributed resilient secondary control system for islanded AC microgrids is proposed. By estimating and compensating the impact of FDI attacks through an extended state observer, the frequency and voltage stability of the islanded AC microgrid is ensured, and the optimal sharing of active power is achieved.

[0030] The extended state observer module sets the frequency control observer to estimate the impact of FDI attack on frequency. The design formula is: Among them, ω i is the actual frequency of the ith DG, To estimate the frequency, In order to estimate the impact of the attack, a voltage control observer is set to estimate the impact of the FDI attack on the voltage. The design formula is as follows: Among them, v i is the actual voltage of the i-th DG, To estimate the voltage, In order to estimate the impact of the attack, the control method is divided into frequency control and voltage control, which are jointly implemented by droop control and secondary control. The goals of frequency control and voltage control are to compensate for the impact of load changes and external interference on the system and maintain the stability of system frequency and voltage.

[0031] The elastic distributed secondary control module combines the output of the extended state observer to precisely control the frequency and voltage of the DG through droop control and secondary control. The goals of frequency and voltage control are to compensate for the impact of load changes and external interference on the system and maintain system frequency and voltage stability. The specific frequency control steps are as follows:

[0032] (1) Basic droop control: The basic droop control strategy is used to adjust the frequency according to the change of active power. The basic formula is: i =ω r -kη i (P i )+u iw , where ω i is the frequency of the ith DG, ω r is the reference frequency of the system, P i is the active power output of the ith DG, kη i is the droop coefficient;

[0033] (2) The secondary control steps are as follows: In order to compensate for the frequency deviation caused by the basic droop control, the secondary control is introduced. The secondary control strategy is used to generate a compensation signal u according to the frequency error. iw : Among them, ω ij represents the frequency difference between the i-th DG and its neighbor j, η ij represents the incremental cost difference of active power, k wi and k pi is the control gain;

[0034] The specific steps of frequency control adjustment are: taking into account the effects of droop control and secondary control, the frequency control formula after adjustment is: Among them, Δ wi represents the actual FDI attack impact, represents the attack impact estimated by the extended state observer;

[0035] The voltage control steps are as follows:

[0036] (1) Basic droop control: The basic droop control strategy is used to adjust the voltage according to the change of reactive power. The basic formula is as follows: i =v r -n i Q i +u iv , where v i is the voltage of the ith DG, v r is the reference voltage of the system, Q i is the reactive power output of the ith DG, n i is the droop coefficient;

[0037] (2) Secondary control: In order to compensate for the voltage deviation caused by the basic droop control, secondary control is introduced. The secondary control strategy is used to generate a compensation signal u according to the voltage error. iv : Among them, u iv represents the voltage difference between the i-th DG and its neighbor j, k vi is the control gain;

[0038] (3) Voltage control adjustment: Taking into account the effects of droop control and secondary control, the adjusted voltage control formula is: Among them, Δ vi represents the actual FDI attack impact, represents the attack impact estimated by the extended state observer.

[0039] The FDI attack model research module is used to study two FDI attack models, including FDI attacks on local actuators and FDI attacks on communication links, and define the impact of FDI attacks on frequency and voltage. When the actuator is attacked by FDI, the injected false data will interfere with the control of frequency and voltage, causing the system to deviate from the preset stable state. When the communication link is attacked by FDI, false data or blocked communication will cause abnormal information transmission between each DG, affecting the effectiveness of global control and possibly leading to instability of the entire microgrid.

[0040] The attack signal estimation and compensation module adjusts the frequency control strategy according to the compensation signal output by the extended state observer. The adjustment formula is: in,

[0041] is the incremental cost of active power, ω ij is the frequency difference term, Δ wi For the actual attack impact, To estimate the impact of the attack, the voltage control strategy is adjusted according to the compensation signal output by the extended state observer. The adjustment formula is: Among them, v ij is the voltage difference term, Δ vi For the actual attack impact, To estimate the impact of the attack.

[0042] Among them, the resilient distributed secondary control module is subjected to false data injection (FDI) attack. The control architecture of the island mode AC (AC) microgrid consists of the network layer, the secondary control layer, and the primary control layer;

[0043] Specifically, the network layer includes: connections between distributed generators. The network layer shows the network topology structure in which multiple DGs are connected to each other through communication links;

[0044] The secondary control layer is specifically: the actuator responsible for frequency control: Actuator responsible for voltage control:

[0045] The observer is specifically: an extended state observer used to estimate the impact of attack signals in frequency control: Extended state observer for estimating attack signal impact in voltage control:

[0046] The elastic distributed secondary control module uses frequency control, combined with the actuator and observer responsible for frequency control, to adjust the frequency of the DG to ensure frequency stability, and voltage control, combined with the actuator and observer responsible for voltage control, to adjust the voltage of the DG to ensure voltage stability.

[0047] Example 1

[0048] An isolated AC microgrid model consisting of four distributed generators (DGs) is established. The communication topology is a ring graph, and the first DG is assumed to be able to obtain a reference value.

[0049] Run the simulation and first enable the primary control (droop control) to control the frequency and voltage of each DG. The goal of the primary control is to adjust the active power P output by the DG through the droop mechanism. i and reactive power Q i In the first 3 seconds, the system operates without attack, and the output voltage, frequency and power of DG are recorded. The primary control equation is: i =ω r -kη i (P i )+u iw , v i =v r -n i Q i +u iv .

[0050] At simulation time t = 3 seconds, a forged data injection attack is launched on the actuators and communication links of some DGs. The specific attack settings are as follows:

[0051] Actuator attack: Inject fake frequency and voltage signals into the actuators of DG1 and DG3. The frequency attack signal is a sine waveform. The voltage attack signal is a triangle wave The amplitude is 1 and the period is 0.4π;

[0052] Communication link attack: Inject fake frequency and voltage information into the communication link between DG2 and DG3. The frequency attack signal is a small sine wave. w =0.05sin(5t)rad / s, the voltage attack signal is a triangle wave with an amplitude of 0.1 and a period of 0.4π;

[0053] Three different attack scenarios were tested: FDI attack on the actuator, FDI attack on the communication link, and FDI attack on both the actuator and the communication link. The purpose of the attack was to disrupt the frequency synchronization and voltage recovery of the microgrid through forged data, resulting in unbalanced power distribution.

[0054] Use the distributed secondary controller through the formula: The microgrid is controlled and the results show that the DG output has oscillation and deviates from the control target. Then the proposed secondary controller against FDI attack is adopted. Compensation control is performed, where the controller parameters when the actuator is attacked are ki=40, bi=100, ci=0.01, and the controller parameters when the actuator is attacked are ki=15, bi=200, ci=0.01. In the absence of an attack, the frequency and voltage of the system remain stable, and the power distribution is optimal. After the FDI attack occurs, the frequency and voltage of the system fluctuate significantly, and the power distribution is unbalanced. After activating the elastic secondary control strategy, the system returns to the reference value in a short time, the frequency and voltage stabilize, and the distribution of active power reaches the optimal level again.

[0055] In summary, the distributed secondary control strategy proposed in this paper is based on an extended state observer and is designed to cope with the impact of FDI attacks on microgrids. The role of the observer is to ensure that the microgrid can still operate stably when attacked by an attack, restore the frequency and voltage to the reference values, and achieve optimal power distribution by estimating and compensating the attack signal.

[0056] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A distributed elastic secondary control system for an islanded AC microgrid, characterized in that: The system includes the following components: extended state observer module, FDI attack model research module, attack signal estimation and compensation module and resilient distributed secondary control module; The extended state observer module is set in each distributed generator DG to estimate the impact of FDI attacks on system frequency and voltage; The FDI attack model research module is used to study two FDI attack models, including FDI attacks on local actuators and FDI attacks on communication links, and define the impact of FDI attacks on frequency and voltage; The attack signal estimation and compensation module uses an extended state observer to estimate the impact of the attack signal and compensates for the attack impact by adjusting frequency and voltage control; The elastic distributed secondary control module combines the output of the extended state observer to accurately control the frequency and voltage of the DG through droop control and secondary control. The control strategy adjusts the control input to compensate for the system deviation caused by the FDI attack. The specific control formula is: i =ω r -kη i (P i )+u iw , v i =v r -n i Q i +u iv , where ω i and v i Represent the frequency and voltage of the i-th distributed generator DG, P i and Q i are the active power and reactive power of the i-th DG, η i (P i ) represents the incremental cost function of active power, u iw and u iv It is the control input item used to compensate for the deviation of frequency and voltage, k and n i are control coefficients, used to adjust the rate of change of frequency and voltage, ω r and v r are the rated frequency and voltage of the system, respectively. When FDI attack exists, the impact of FDI attack on system frequency and voltage is estimated by extending the state observer module. According to the above estimation results, the distributed secondary control strategy is adjusted to restore the frequency and voltage to the reference value and achieve the optimal active power sharing, that is, the active power incremental cost η between each DG i (P i ) is consistent, where the dynamic behaviors of frequency and voltage control under FDI attack are obtained, and the frequency control term u for frequency control is generated by the extended state observer. iw and the voltage control term u for voltage control iv , in order to achieve the above goals, the control input u iw and u iv Calculated using the following integral formula: Among them, ω ij represents the frequency difference term, η ij represents the incremental cost difference term, v ij represents the voltage difference term, a ij It is the adjacency matrix element of the communication network, indicating whether there is a communication connection between the two DGs i and j. i Is to indicate whether i DG receives the reference value; k wi 、k pi and k vi It is the control coefficient, which is used to adjust the rate of change of frequency and voltage. By adjusting the frequency and voltage control inputs, it can achieve coordinated control among various distributed generators without a central controller.

2. A distributed elastic secondary control system for an islanded AC microgrid according to claim 1, characterized in that: The extended state observer module estimates the impact of the attack signal on the system frequency and voltage, thereby compensating for the impact, ensuring that the system frequency and voltage can be restored to the reference value and achieving optimal active power sharing. The algorithm formula for estimating the impact of the attack signal on the system frequency and voltage is: Where, Δ wi and Δ vi Represent the influence of frequency and voltage attack signals respectively, and is the observed frequency and voltage attack signal, ω i and v i are the actual frequency and voltage of the i-th distributed generator DG, ω i and v i are the estimated frequency and voltage, u wi and u vi These are the control inputs for frequency and voltage respectively.

3. A distributed elastic secondary control system for an islanded AC microgrid according to claim 1, characterized in that: The FDI attack model research module is used to study two FDI attack models, including FDI attacks on local actuators and FDI attacks on communication links, and defines the impact of FDI attacks on frequency and voltage. For FDI attacks on local actuators, the attack signal is injected into the control signal, changing the secondary control data. The attack model is: Among them, u iw and u iv are the control inputs for frequency and voltage, ω ij and v ij Represent the frequency and voltage differences, k wi 、k pi and k vi is the control coefficient, δ i is an attack indicator. When i DGs are attacked, δ i =1, otherwise δ i =0, and It's an attack signal.

4. A distributed elastic secondary control system for an islanded AC microgrid according to claim 3, characterized in that: The FDI attack model research module is used to study two FDI attack models, including FDI attacks on local actuators and FDI attacks on communication links, and define the impact of FDI attacks on frequency and voltage. For FDI attacks on communication links, the attack signal is injected into the communication data between DGs, changing the information received from neighboring DGs. The attack model is: Among them, ω i and v i denote the frequency and voltage of the i-th distributed generator (DG), η i is the incremental cost, and It is the frequency and voltage information after being attacked. is the incremental cost after being attacked.

5. A distributed elastic secondary control system for an islanded AC microgrid according to claim 3, characterized in that: The FDI attack model research module is used to study two FDI attack models, including FDI attacks on local actuators and FDI attacks on communication links. For FDI attacks on communication links, and It is the frequency and voltage information after being attacked. is the incremental cost after being attacked, defined as: Among them, δ ij is an attack indicator. When the communication link i and j is attacked, δ ij =1, otherwise δ ij =0, and The two attack models demonstrate how FDI attacks interfere with frequency and voltage control by injecting false data, thereby undermining system stability. Specifically, they manifest as follows: Frequency and voltage deviation: The attack signal causes the frequency and voltage to deviate from their reference values, undermining system stability; Power sharing failure: Due to the interference of the attack signal, the optimal sharing of active power and reactive power cannot be achieved.

6. A distributed elastic secondary control system for an islanded AC microgrid according to claim 1, characterized in that: The attack signal estimation and compensation module uses an extended state observer to estimate the impact of the attack signal and compensates for the attack impact by adjusting the frequency and voltage control. The calculation formula for adjusting the frequency and voltage is: Among them, Δ wi and Δ vi It's the actual attack signal. and is the attack signal estimated by the extended state observer.

7. A distributed elastic secondary control system for an islanded AC microgrid according to claim 1, characterized in that: The dynamic behavior of frequency and voltage control of the resilient distributed secondary control module under FDI attack is analyzed. The frequency control term u for frequency control is generated by the extended state observer. iw and the voltage control term u for voltage control iv During the process, ij represents the frequency difference term, defined as η ij represents the incremental cost difference term, which is defined as: v ij represents the voltage difference term, which is defined as: where ω ij represents the frequency difference between the i-th distributed generator and the j-th distributed generator, v ij represents the voltage difference between the i-th distributed generator and the j-th distributed generator, η ij represents the incremental cost difference between the i-th distributed generator and the j-th distributed generator.

8. A distributed elastic secondary control system for an islanded AC microgrid according to claim 1, characterized in that: The elastic distributed secondary control module needs to achieve frequency and voltage synchronization during the process of adjusting the frequency and voltage control input. The algorithm formula used is: Among them, ω i represents the frequency of the i-th distributed generator, w ref Indicates the system reference frequency, v i represents the voltage of the i-th distributed generator, v ref Indicates the system reference voltage, η i is the incremental cost of active power of the voltage of the i-th distributed generator, η j is the incremental cost of active power of the jth distributed generator.

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