CN110768301A - Micro-grid frequency synchronization anti-attack cooperative control method - Google Patents

Micro-grid frequency synchronization anti-attack cooperative control method Download PDF

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CN110768301A
CN110768301A CN201910978587.6A CN201910978587A CN110768301A CN 110768301 A CN110768301 A CN 110768301A CN 201910978587 A CN201910978587 A CN 201910978587A CN 110768301 A CN110768301 A CN 110768301A
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齐冬莲
陈郁林
张建良
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Zhejiang University ZJU
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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
    • H02J3/40—Synchronising a generator for connection to a network or to another generator
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
    • H02J3/381—Dispersed generators

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Abstract

The invention discloses a micro-grid frequency synchronization anti-attack cooperative control method, which adopts a specially designed control rate to control the frequency of a micro-grid and can completely eliminate any constant attack on a controller on the premise of ensuring the frequency synchronization of a system. The control rate is integrated on the basis of the traditional distributed control method, and then corresponding frequency state quantity is subtracted, so that the aim of eliminating constant value attack applied by a controller is fulfilled, and the convergence of the control method is strictly proved by utilizing a final value theorem; compared with the existing method for resisting constant attack, the method provided by the invention does not need to establish a complex evaluation mechanism to evaluate the credibility of the neighbor node information, does not need an additional communication network to assist in eliminating the attack, and can completely eliminate the influence of the constant attack on the system.

Description

Micro-grid frequency synchronization anti-attack cooperative control method
Technical Field
The invention relates to a micro-grid frequency synchronization cooperative control method, in particular to a micro-grid frequency synchronization anti-attack cooperative control method.
Background
An alternating current microgrid information physical system (CPS) is an important component of an active power distribution network. Due to the presence of distributed power Supplies (DGs), frequency secondary control in micro-grids often employs a distributed coordinated control architecture. However, under deep fusion of information and power, the micro-grid CPS is vulnerable to information attack. Among them, the injection type constant value attack (covert attack) can disturb the normal operation of the system under the condition that the system is not easily perceived.
The distributed control algorithm is an effective control means of a micro-grid containing a large number of distributed power supplies, and is easy to attack by a network, and due to the lack of a global observation mechanism, the distributed control algorithm cannot cope with hidden attacks (such as constant value attacks). How to resist the influence of the hidden attack on the distributed control has important significance on the stable operation of the micro-grid.
The invention provides a novel micro-grid frequency synchronization cooperative control method capable of resisting constant attack, aiming at the problem that a cooperative control algorithm of micro-grid frequency synchronization is easy to be attacked by constant.
The DGs supply power to the microgrid through inverters. The inverter is mainly a voltage-type inverter and mainly comprises a DC power supply, a bridge inverter circuit, a power controller, a voltage controller, a current controller, a filter and the like. In order to accurately describe a mathematical model of the voltage-type inverter, a large-signal modeling method is adopted to model the voltage-type inverter, and the dynamic characteristics after modeling can be expressed as follows:
Figure BDA0002234454770000011
wherein x isiIs a system status parameter.
In power controllers, droop control techniques are used to control the voltage and frequency of the inverter output. Which simulates the relation between the active/frequency and the reactive/voltage amplitude of a synchronous generator
Figure BDA0002234454770000012
Wherein, ω isiAnd vmag,iRespectively, inverter i outputs a voltage and a frequency. PiAnd QiThe output of inverter i is active and reactive, respectively. m ispiAnd nqiRespectively, the active and reactive droop coefficients of inverter i, which can be reversedThe rated value of the converter is obtained. OmegaNiAnd VNiFor the frequency and voltage set points (also frequency and voltage when the inverter is in idle operation), the secondary frequency modulation and voltage regulation (secondary control) of the system can be carried out by adjusting the two parameters.
The frequency drop and voltage droop caused by droop control need to be compensated by the secondary control. The secondary control restores the frequency and the voltage to the normal working range by adjusting the frequency and the voltage set point, and can be realized by distributed control.
Differentiating the active/frequency droop relationship to obtain
Figure BDA0002234454770000021
In the formula uiIs a control input.
The conventional distributed control rate is generally
Figure BDA0002234454770000022
Wherein, ω isref50Hz is the nominal frequency. k is a radical ofωIs a control coefficient. Then, a secondary control frequency set point is derived according to the differentiated active/frequency droop relation as
Figure BDA0002234454770000023
Therein
Figure BDA0002234454770000024
Can be obtained from the following power controller dynamics
Figure BDA0002234454770000025
The above process can be described in detail in the references "Abhinav S, Modares H, Lewis F L, et al. Synchronyin network microorganisms under att attacks [ J ]. IEEE Transactions on Smart Grid,2017,9(6):6731 and 6741".
According to the control rate and the dynamic characteristics of the system, primary droop control is combined, and under an ideal communication environment, the DGs frequency can be distributively synchronized. However, because communication among DGs is involved, the algorithm is easily affected by attacks, so that the control algorithm fails and the stability of the microgrid system is damaged.
Disclosure of Invention
In order to solve the above problems, the present invention provides a micro-grid frequency synchronization anti-attack cooperative control method, so as to achieve the purpose of eliminating the attack influence applied to the micro-grid frequency synchronization cooperative control.
The method and the device do not need to establish a complex evaluation mechanism to evaluate the reliability of the neighbor node information, do not need an additional communication network to assist in eliminating the attack, and can completely eliminate the influence of the constant attack on the system.
The technical scheme adopted by the invention is as follows:
a micro-grid frequency synchronization anti-attack cooperative control method is characterized in that a specially designed micro-grid frequency synchronization anti-attack control rate is adopted to control the micro-grid frequency, the method can completely resist constant attack, and the designed control rate is as follows:
Figure BDA0002234454770000031
wherein, ω isi(t) is the frequency of the distributed power supply i, kωTo control the gain, ωrefIs a frequency reference value, namely the rated frequency of the system is 50Hz, N is the number of distributed power supplies, NiIs the number of neighbors of the distributed power supply i, biRepresenting the connection gain, when node i is connected to the leader node, b i1, otherwise bi＝0。
The invention has the beneficial effects that:
under the condition that extra evaluation calculation and communication network are not needed, the method of the invention can completely eliminate the influence of constant value attack on the whole system, and can still keep the synchronization of the frequency of the microgrid under the condition that the attack exists.
Drawings
Fig. 1 is a structural diagram of a microgrid system for a verification experiment of the present invention.
FIG. 2 is a schematic diagram of the experimental constant attack of the present invention.
Fig. 3 is an experimental screenshot of the control effect of the conventional distributed frequency synchronization algorithm under the attack-free condition.
Fig. 4 is an experimental screenshot of the control effect of the conventional distributed frequency synchronization algorithm when DG3 is under constant attack.
Fig. 5 is an experimental screenshot of the control effect of the conventional distributed frequency synchronization algorithm when all DGs are under constant attack.
Fig. 6 is an experimental screenshot of the control effect of the attack-resistant distributed frequency synchronization algorithm when DG3 is attacked.
Fig. 7 is an experimental screenshot of the control effect of the anti-attack distributed frequency synchronization algorithm when all DGs are attacked.
Detailed Description
The invention is described in further detail below with reference to the figures and the embodiments.
The detailed design process of the invention is as follows:
1) on the basis of the traditional distributed control method, integral operation is carried out, and then corresponding frequency state quantity is subtracted, so that a brand new control rate is provided, and the aim of eliminating constant value attack applied by a controller can be achieved.
2) In order to analyze the convergence of the designed control system, the dynamic characteristics of the system are subjected to Laplace transform, and then the control rate is proved to be capable of ensuring that the frequency of each DG gradually converges to the reference value of the frequency by using the final value theorem.
The method comprises the following specific steps:
1) the frequency synchronization anti-attack control rate of the micro-grid is designed, based on a traditional distributed micro-grid frequency synchronization cooperative control algorithm, the distributed control rate capable of resisting constant attack is designed, and the designed control rate is as follows:
Figure BDA0002234454770000041
wherein, ω isi(t) is the frequency of the distributed power supply i, kωTo control the gain, ωrefIs a frequency reference value, namely the rated frequency of the system is 50Hz, N is the number of distributed power supplies, NiIs the number of neighbors of the distributed power supply i, biRepresenting the connection gain, when node i is connected to the leader node, b i1, otherwise bi＝0。
2) The convergence of the proposed control rate is demonstrated using the laplace transform and the final theorem.
The frequency dynamic characteristic of the whole system under the control rate (1) can be expressed in the form of a vector
Figure BDA0002234454770000042
Wherein ω is [ ω ═ ω [ [ ω ]1,ω2,...,ωn]T；
L is a Laplace matrix of the network topology, which is defined as
Figure BDA0002234454770000043
A is the adjacency matrix of the network topology, aijAre elements of the adjacency matrix. B ═ diag { B ═ B { (B) }iIs the connection gain matrix, biIf 1, indicating that node i is connected to the leader node, otherwise bi＝0。1nIs an n-dimensional column vector with elements of 1.
The frequency dynamics under constant value attack are:
Figure BDA0002234454770000044
wherein C ═ C1,c2,…,cn]TIs an attack vector.
Next, the frequency control characteristic under the constant value attack is analyzed by the laplace transform method.
The Laplace transform is performed on (3), then
Where s is the complex variable after transformation, ω(s) is the Laplace transform of ω (t), ω (0) is the initial vector of ω (t), and has
Figure BDA0002234454770000046
Then, deriving ω(s) then
Figure BDA0002234454770000047
Wherein I is an identity matrix. Then, the two sides of the equation are multiplied by s simultaneously to obtain
Figure BDA0002234454770000051
Because of [(s)2+skω)I+kω(L+B)]Is reversible, then
Figure BDA0002234454770000052
According to the theorem of final value, then there are
The process of the present invention is further illustrated by the specific application below.
The specific embodiment of the invention:
the validity of the method is verified in a microgrid system as shown in fig. 1. The microgrid comprises 4 distributed power sources and three integrated loads (the sum of the load demands connected to the same bus). The installed capacity, primary control droop coefficient, and integrated load requirements of the distributed power supply are shown in tables 1 and 2, respectively.
TABLE 1
Figure BDA0002234454770000054
TABLE 2
And assuming that the micro-grid is operated away from the main grid, the output power of the distributed power supply in the micro-grid operated in an island mode always meets the load requirement.
The whole simulation process event comprises the following steps: and when t is 0s, the micro-grid is separated from the main grid to operate. And adding secondary control when t is 1.25 s. When t is 2.5s, a constant attack is injected. Load demands in the island micro-grid before t is 3.75s are only L1 and L2, and load L3 is connected when t is 3.75 s.
Fig. 2 shows two constant attack scenarios, namely DG3 controller alone (fig. 2(a)) and all DGs controllers (fig. 2(b)), with the attack vectors C ═ 0,0,1,0, respectively]TAnd C ═ 1,2,3,4]T。
The experimental screenshots are as follows:
(1) when the microgrid system is not under attack, under the traditional frequency secondary control method (i.e. the traditional distributed control rate is adopted to control the microgrid frequency), the frequency of the DGs is as shown in fig. 3. Therefore, the traditional secondary control can realize frequency synchronization under load change when the micro-grid island operates under the condition of no attack. .
(2) Fig. 4 and 5 show the output frequency of each distributed power source under the conventional secondary control method in the attack scenarios of fig. 2(a) and 2(b), respectively. It can be seen from the figure that in both attack scenarios, the system frequency fluctuates beyond the allowable range and cannot maintain synchronization. And under the condition that four DGs are attacked, the system frequency fluctuation is larger, and the consequence is more serious. Fig. 4 and 5 demonstrate that a constant value attack has a large impact on a conventional secondary control strategy, so that the secondary control loses the effect of its application.
(3) Fig. 6 and fig. 7 respectively show the control effect diagrams of the distributed anti-attack frequency synchronization control method of the present invention under two attack situations. It can be seen from the figure that the distributed anti-attack frequency synchronization control method can completely resist the constant value attack, and even if all DGs are attacked by the constant value attack, the method can still completely eliminate the influence of the attack and keep the frequency synchronization of the system. Therefore, the experimental result proves the effectiveness of the provided distributed anti-attack frequency synchronization control method in resisting constant value attack.
The foregoing detailed description is intended to illustrate and not limit the invention, which is intended to be within the spirit and scope of the appended claims, and any changes and modifications that fall within the true spirit and scope of the invention are intended to be covered by the following claims.

Claims (1)

1. A micro-grid frequency synchronization anti-attack cooperative control method is characterized by comprising the following steps: the method is characterized in that the control rate u is expressed by the formula (1)iTo control the frequency of the microgrid;
Figure FDA0002234454760000011
wherein, ω isi(t) is the frequency of the distributed power supply i, kωTo control the gain, ωrefIs a frequency reference value, namely the rated frequency of the system is 50Hz, N is the number of distributed power supplies, NiIs the number of neighbors of the distributed power supply i, biRepresenting the connection gain, when node i is connected to the leader node, bi1, otherwise bi＝0。
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112701729A (en) * 2021-01-08 2021-04-23 东北大学 Micro-grid distributed cooperative control system and method based on edge calculation
CN112994082A (en) * 2021-02-01 2021-06-18 浙江工业大学 Distributed elastic voltage recovery and current distribution method for direct-current micro-grid

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106169756A (en) * 2016-07-15 2016-11-30 河海大学 A kind of meter and the isolated island microgrid frequency cooperative control method of economic performance
US9941699B2 (en) * 2014-11-21 2018-04-10 Siemens Industry, Inc. Systems, methods and apparatus for improved management and control of energy delivery systems
CN108075488A (en) * 2017-12-05 2018-05-25 燕山大学 The isolated island micro-capacitance sensor hierarchical control method of communication data disturbance is considered under CPS concepts
CN108258681A (en) * 2018-01-11 2018-07-06 南京邮电大学 The security incident trigger control method of LOAD FREQUENCY control system under a kind of DoS attack
CN108521345A (en) * 2018-04-04 2018-09-11 燕山大学 A kind of information physical collaboration countermeasure for the isolated island micro-capacitance sensor considering communication disruption

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9941699B2 (en) * 2014-11-21 2018-04-10 Siemens Industry, Inc. Systems, methods and apparatus for improved management and control of energy delivery systems
CN106169756A (en) * 2016-07-15 2016-11-30 河海大学 A kind of meter and the isolated island microgrid frequency cooperative control method of economic performance
CN108075488A (en) * 2017-12-05 2018-05-25 燕山大学 The isolated island micro-capacitance sensor hierarchical control method of communication data disturbance is considered under CPS concepts
CN108258681A (en) * 2018-01-11 2018-07-06 南京邮电大学 The security incident trigger control method of LOAD FREQUENCY control system under a kind of DoS attack
CN108521345A (en) * 2018-04-04 2018-09-11 燕山大学 A kind of information physical collaboration countermeasure for the isolated island micro-capacitance sensor considering communication disruption

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
SHANKAR ABHINAV: "Synchrony in Networked Microgrids Under Attacks", 《IEEE TRANSACTIONS ON SMART GRID》 *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112701729A (en) * 2021-01-08 2021-04-23 东北大学 Micro-grid distributed cooperative control system and method based on edge calculation
CN112701729B (en) * 2021-01-08 2022-09-27 东北大学 Micro-grid distributed cooperative control system and method based on edge calculation
CN112994082A (en) * 2021-02-01 2021-06-18 浙江工业大学 Distributed elastic voltage recovery and current distribution method for direct-current micro-grid
CN112994082B (en) * 2021-02-01 2022-05-03 浙江工业大学 Distributed elastic voltage recovery and current distribution method for direct-current micro-grid

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