Automatic control system information network static model and fault analysis method thereof

Abstract

The invention provides an automatic control system information network static model and a fault analysis method thereof, and belongs to the field of electric power information physical system and electric power system automation. Wherein the static model comprises an information network element layer, a communication link layer and a network element layer; the information network element layer comprises a measurement element unit, an information transmission path unit, an information calculation and processing unit and an execution element unit, and is used for displaying an information flow transmission process of the automatic control system; the communication link layer is used for representing a communication link sub-model corresponding to any sub-model in the information network element layer; the network element layer is used for representing the network element sub-model corresponding to any communication link sub-model. According to the method, the association between the information flow of the service model of the automatic control system and the actual system communication link and element is realized, the propagation path of the information network abnormity and fault in the power automatic control system can be quickly positioned, and the fault analysis of information physical coupling can be conveniently carried out.

Description

Technical Field

[0001] The invention belongs to the field of electric power information physical system and electric power system automation, and in particular relates to an automatic control system information network static model and a fault analysis method thereof. Background Art

[0002] In order to achieve real-time perception, dynamic control and intelligent services for modern power systems, more advanced computing, communication and control links are tightly coupled with the traditional physical systems of power systems to form information-physical systems. Closed-loop automatic control systems are carried on the power communication system. As an important component of the power secondary system, automatic control system failures can affect the physical power grid through the path of information-physical coupling. At present, there are barriers between the information network monitoring system and the power automatic control system business of the power system, making it difficult to directly analyze the impact of information disturbances and failures on specific automatic control system businesses. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the existing technology and propose an automatic control system information network static model and its fault analysis method. The present invention realizes the association between the information flow of the automatic control system business model and the actual system communication links and components. Based on the association model, the propagation path of information network anomalies and faults in the power automatic control system can be quickly located, and it is convenient to carry out information-physical coupling fault analysis.

[0004] The embodiment of the present invention proposes an automatic control system information network static model, including: an information network component layer, a communication link layer, and a network component layer;

[0005] The information network element layer includes a measurement element unit composed of multiple measurement element sub-models, an information transmission path unit composed of an information transmission path sub-model connecting each measurement element sub-model, an information calculation and processing unit, and an execution element unit composed of multiple execution element sub-models; the information network element layer is used to display the information flow transmission process of the automatic control system, including the interaction between the automatic control system and the physical power grid;

[0006] The communication link layer is used to represent the communication link sub-model corresponding to any sub-model in the information network element layer;

[0007] The network element layer is used to represent the network element sub-model corresponding to any communication link sub-model in the communication link layer; the network element sub-model is used to indicate the communication network elements included in the corresponding communication link.

[0008] In a specific embodiment of the present invention, the measuring element unit is used to obtain the required physical quantity and convert it into the input of the information network; the information transmission path unit is used to transmit various types of data; the information calculation and processing unit is used to generate control instructions of the system based on the set logic; the execution element unit is used to convert the control instructions carried by the information network information into actual physical quantities.

[0009] In a specific embodiment of the present invention, the static model construction method includes:

[0010] Firstly, based on the coupling relationship between information and physical system, the information network component layer is constructed, which includes: physical quantity acquisition link, transmission path link, calculation and analysis link, downlink path link and instruction execution link. The information network component layer also establishes the information processing process function carried by each link respectively; secondly, based on the virtual channel of the power grid communication system, the communication link layer is established, including: the link model carrying information, the primary and backup routes and the link status; finally, based on the physical component model of the communication network, it is associated with the communication link.

[0011] In a specific embodiment of the present invention, the step of constructing the information network element layer includes:

[0012] 1) Construct the measurement component sub-model;

[0013] For any measuring element n m , whose input is the state of the physical grid Output is the collection of system status F m It represents the measurement matrix, which represents the mapping of the actual signal after the acquisition process;

[0014] The sub-model expression corresponding to the measurement element is as follows:

[0015]

[0016] 2) Construct the actuator sub-model;

[0017] For any execution node n a , whose input is the control instruction of the upper branch Output is the receiving instruction of the actuator F a represents the execution matrix, which represents the mapping of control signals through the execution process;

[0018] The sub-model expression corresponding to the execution node is as follows:

[0019]

[0020] 3) Construct the information transmission pathway sub-model;

[0021] For any information transmission path T k , respectively, using column vectors and Represents the data of its input node and output node, then the information transmission path sub-model expression is as follows:

[0022]

[0023] In the formula, the matrix M k is a square matrix, whose order is the same as the vector and same;

[0024] 4) Construct information computing and processing units;

[0025] For any business, use column vector and The expressions representing the data, information calculation and processing units of its input nodes and output nodes are as follows:

[0026]

[0027] In the formula, F c Represents the mapping function corresponding to this link.

[0028] In a specific embodiment of the present invention, it also includes:

[0029] When the measured signal is collected without error, F m The element of F is 1; when the control signal is executed without error, a The element of M is 1; when the information transmission path is not disturbed, k is an identity matrix.

[0030] In a specific embodiment of the present invention, the establishing of the communication link layer includes:

[0031] 1) Construct a data link set associated with information elements;

[0032] The communication link layer is a collection of different data links from the start information element to the end information element, expressed as follows:

[0033]

[0034] Among them, Lk ij represents the set of communication links from information element i to information element j, represents the kth communication link from information element i to information element j, k = 1, 2, ..., N, and there are N communication link paths in the set;

[0035] 2) Obtain the status of the communication link;

[0036] For each communication link Establish their state bits respectively l and status flag P l , where State l =0, when interrupted, State l =-1, State when bit error occurs l =1.

[0037] In a specific embodiment of the present invention, it also includes:

[0038] When State l =1, the bit error rate of the communication link is recorded.

[0039] In a specific embodiment of the present invention, the physical component model based on the communication network is associated with the communication link, including:

[0040] 1) For any communication link Let the associated set be:

[0041]

[0042] in, is the mth communication channel of the communication link k between information element i and information element j, and M is the total number of communication channels;

[0043] 2) Obtain the status of the communication channel;

[0044] For any communication channel Get its state bit State c and status flag P c , where State c =0, when interrupted, State c =-1, State when bit error occurs c =1.

[0045] In a specific embodiment of the present invention, it also includes:

[0046] When State c =1, the bit error rate of the channel is recorded.

[0047] The embodiment of the present invention further proposes a fault analysis method based on the above static model, comprising:

[0048] 1) Establish the propagation path of the impact of component failure at each level;

[0049] For any communication channel Its abnormal state According to the communication channel and communication link association, the communication link between communication elements i and j Status The calculation expression is as follows:

[0050]

[0051] Where η m,k is the influence weight of the mth communication network element on the kth path;

[0052] The fault impact is propagated to the information network element layer in a weighted manner according to the status of the communication link, namely:

[0053]

[0054] In the formula, ζ k is the kth path pair LK ij The weight of influence;

[0055] 2) Analysis of the impact of information components on automatic control systems;

[0056] For any information element LK ij ,The impact of its on the automatic control system is based on the ,information-physical coupling model.,First, the impact of the abnormal information component on the ,information volume on which it carries is analyzed, and then the impact of the information volume on the ,key physical indicators of the physical system is analyzed:

[0057]

[0058] Among them, λ p is the set physical quantity, s c is the amount of information in the automatic control system; f is the fault impact equation of information-physical coupling, which is the product of the sensitivity of information elements to information flow and the sensitivity of information flow to physical quantity.

[0059] Features and beneficial effects of the present invention:

[0060] The present invention is an improvement on the information flow network model based on a directed graph. While retaining the basic architecture of the information network element model, a measurement element sub-model and an execution element sub-model are added to make the interaction path between the information network and the physical power grid clear, which is convenient for fault location and full-process analysis. In addition, the information network element is used as the business layer of the information flow, and the communication link layer and the network element layer are expanded downward, so that the information network model and the power system communication system link and the actual communication network element are associated. Compared with a single information network element model, it is more in line with the actual power system and breaks down barriers for the application of the actual power system.

[0061] 1) The static model construction of the present invention associates the automatic control system business flow with the communication link and the communication system components, which facilitates the analysis of the propagation path of faults and disturbances occurring at the information network component layer to the automatic control system business, and facilitates the quantitative analysis of faults in information-physical fusion.

[0062] 2) The present invention breaks down the barriers between information networks and automatic control system services, helps the automatic control system analyze the impact of communication system failures on the service, and effectively improves the resilience of the power secondary system.

[0063] 3) The information network static model constructed by the present invention is applicable to various automatic control services, such as automatic power generation control, automatic voltage control, etc., and can be used as an advanced application to assist the construction and safe operation of such systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 It is a structural diagram of a static model of an automatic control system information network according to an embodiment of the present invention. DETAILED DESCRIPTION

[0065] The present invention proposes an automatic control system information network static model and a fault analysis method, which are further described below with reference to specific embodiments of the drawings.

[0066] The embodiment of the present invention proposes a static model of an automatic control system information network, the structure of which is as follows: Figure 1 As shown, it includes: information network element layer, communication link layer, and network element layer.

[0067] The information network element layer includes a measurement element unit composed of multiple measurement element sub-models, an information transmission path unit composed of an information transmission path sub-model connecting each measurement element sub-model, an information calculation and processing unit, and an execution element unit composed of multiple execution element sub-models. The information network element layer is used to display the information flow transmission process of the automatic control system, including the interaction between the automatic control system and the physical power grid.

[0068] Furthermore, the measuring element unit is used to obtain the required physical quantity and convert it into the input of the information network; the information transmission path unit is used to transmit various types of data, such as the transmission of acquisition, control and other data between upper and lower units; the information calculation and processing unit is used to generate system control instructions based on the set logic; the execution element unit is used to convert the control instructions carried by the information network information into actual physical quantities.

[0069] The communication link layer is used to represent a specific communication link sub-model corresponding to any sub-model in the information network element layer. Figure 1The communication link layer in the figure shows the communication link submodel corresponding to an information transmission path submodel in the information network component layer. In addition, the communication links corresponding to other submodels in the information network component layer can also be represented in the communication link layer. Figure 1 As shown in FIG. 1 , the communication link submodel corresponding to the information transmission path submodel in the communication link layer indicates that the information transmission path may include multiple communication links. Specifically, the information transmission path, in this embodiment, is recorded as an uplink path 3 in the information network element layer, and includes 4 communication link submodels in the communication link layer (respectively Figure 1 As shown in the communication link 1, communication link 2 is connected to communication link 2-1, communication link 2 is connected to communication link 2-2, and communication link 2 is connected to communication link 2-3), the composition within each link is different, but the starting point and the end point are the same. In this embodiment, the starting points of the four communication links are all measurement nodes, and the end points are the Control Center. The control center here is a generalized representation of the information calculation and processing unit of the information network element layer.

[0070] The network element layer is used to represent the network element sub-model corresponding to any communication link sub-model in the communication link layer, and the network element sub-model is used to indicate that the corresponding communication link may include multiple specific communication network elements, such as routers, optical fibers, etc. Figure 1 The network element layer in Figure 1 shows the network element sub-model corresponding to the communication link 2-3 in the communication link layer. Figure 1 As shown, the network element sub-model shows that the link is composed of three routers and five actual network transmission lines.

[0071] Furthermore, this embodiment also proposes a method for constructing a static model of the information network of the automatic control system. The method first constructs the information network component layer of the closed-loop control system based on the information-physical system coupling relationship, which specifically includes five parts: physical quantity acquisition link, transmission path link, calculation and analysis link, downlink path link and instruction execution link, and establishes the information processing process function carried by each part; secondly, a communication link layer is established based on the virtual channel of the power grid communication system, including the specific link model of the information carried, the main and standby routes and the link status for abstract construction; finally, based on the specific physical component model of the communication network, it is associated with the communication link; the method specifically includes the following steps:

[0072] 1) Construct the information network component layer of the automatic control system with cyber-physical coupling, including:

[0073] 1-1) Construct the measurement component sub-model.

[0074] In this embodiment, the measurement element sub-model is the information source of the closed-loop control system and the core of the interaction from physical quantity to information. m , whose input is the state of the physical grid Output is the collection of system status F m Represents the measurement matrix, which represents the mapping of the actual signal after the acquisition process, in which there may be bit errors, delays, etc. If there is no error F m The element of is 1. The sub-model expression corresponding to the measurement element is as follows:

[0075]

[0076] 1-2) Construct the actuator sub-model.

[0077] In this embodiment, the execution element is the output end of the closed-loop control system and the core of the information to the physical power grid operation. a , whose input is the control instruction of the upper branch Output is the receiving instruction of the actuator F a represents the execution matrix, which represents the mapping of the control signal through the execution process, in which there may be misoperation, bit error, etc. If there is no error F a The element of is 1. The sub-model expression corresponding to this execution node is as follows:

[0078]

[0079] 1-3) Construct the information transmission path sub-model.

[0080] In this embodiment, most information transmission paths can be represented as a directed transmission path with a path gain of 1. When there is a disturbance, the information carried by it may experience multiple types of changes such as delay and error. Therefore, for any information transmission path T k , respectively, using column vectors and Represents the data of its input nodes and output nodes, then the information transmission path sub-model can be described as:

[0081]

[0082] In the formula, the matrix M k is a square matrix, whose order is the same as the vector and When no information disturbance occurs, M k It can be regarded as an identity matrix; when there is a disturbance, its matrix elements will undergo a correction related to the disturbance.

[0083] 1-4) Construct information computing and processing units.

[0084] In this embodiment, the information calculation and processing unit is the analysis and calculation link of the information flow, which is mapped to output data through a specific mapping function (such as control instruction calculation and physical component operation). c There is only one, using column vectors and The data, information calculation and processing units representing its input nodes and output nodes can be described as:

[0085]

[0086] In the formula, F c Represents the mapping function corresponding to this link. For different closed-loop control models and automatic control software, it is given according to the actual business. For example, the proportional-integral control in frequency control is not necessarily a linear function.

[0087] 2) Build the communication link layer, including:

[0088] 2-1) Construct a data link set associated with information components.

[0089] In this embodiment, for different data types (such as frequency acquisition, capacitor switching signal, etc.), the corresponding number of propagation paths in the link is different. In addition, the data will pass through different intermediate sites during the transmission between the starting site and the ending site. Therefore, the communication link layer can be modeled as a sequence from the starting information element to the ending information element (such as Figure 1 The collection of different data links in (from the measurement node to the control center) is as follows:

[0090]

[0091] Among them, Lk ij represents the set of communication links from information element i to information element j, represents the kth communication link from information element i to information element j, k = 1, 2, ..., N, and there are N specific communication link paths in the set, (N ≥ 1). It should be noted here that the specific number N of communication links between different information elements i and j is different and is given according to different communication networks.

[0092] 2-2) Obtain the status of the communication link;

[0093] In this embodiment, for each specific communication link Establish their state bits respectively l and status flag P l, corresponding to normal / different abnormalities (normal: State l =0; Interrupt State l =-1; Error State l =1); and the degree of its abnormality (only bit errors are effective and the bit error rate is recorded).

[0094] 3) Based on the results of steps 1) and 2), the communication network element is associated with the communication link; the specific steps are as follows:

[0095] 3-1) Communication network elements are the actual physical components of the power grid secondary system, such as routers and optical fibers. There is a specific relationship between their elements and the communication link layer. For a single communication link Its associated communication network element set is:

[0096]

[0097] in, is the mth channel of the communication link k between nodes i and j, and M is the total number of signals. It should be noted that different paths The value of M is different.

[0098] 3-2) Obtaining the status of a communication network element; for a certain actual communication network element Its status bit comes from the collected information of the actual power grid secondary monitoring, which is similar to the status definition of the communication link. c and status flag P c , corresponding to normal / different abnormalities (normal: State c =0; Interrupt State c =-1; Error State c =1); and the degree of its abnormality (only bit errors are effective and the bit error rate is recorded).

[0099] Furthermore, this embodiment also proposes a fault analysis method based on the above-mentioned automatic control system information network static model, including:

[0100] 1) Establish the propagation path of the impact of component failure at each level.

[0101] In this embodiment, for any communication network element Its abnormal state According to the communication network element and the communication link association, the state of the communication link k between nodes i and j can be jointly determined by its associated communication network element and the influence weight of different communication network elements on the path, that is,

[0102]

[0103] Where ηm,k is the influence weight of the mth communication network element on the kth path. At this time, the fault of the communication network element is propagated to the communication link through the association relationship, and the state of the communication link can be obtained at this time; then, according to the state of the communication link, the fault impact is propagated to the information network element layer in a weighted manner, that is:

[0104]

[0105] In the formula, ζ k is the kth path pair LK ij The influence weight of .

[0106] In summary, we can derive the propagation path of faults from communication physical components to information network abstract components.

[0107] 2) Analysis of the impact of information components on automatic control systems;

[0108] For any information element LK ij , given its state, its impact on the automatic control system is based on the information-physical coupling model. First, the impact of the abnormality of the information element on the amount of information it carries is analyzed, and then the impact of the amount of information on the key physical indicators of the physical system is analyzed:

[0109]

[0110] Among them, λ p is a key physical quantity (such as voltage, frequency), s c is a certain amount of information (such as instructions, collection) of the automatic control system, f is the fault impact equation of information-physical coupling, and is the product of the sensitivity of information elements to information flow and the sensitivity of information flow to physical quantity.

Claims

1. A static model of an automatic control system information network, characterized in that: include: Information network component layer, communication link layer, network component layer; The information network element layer includes a measurement element unit composed of multiple measurement element sub-models, an information transmission path unit composed of an information transmission path sub-model connecting each measurement element sub-model, an information calculation and processing unit, and an execution element unit composed of multiple execution element sub-models; the information network element layer is used to display the information flow transmission process of the automatic control system, including the interaction between the automatic control system and the physical power grid; The communication link layer is used to represent the communication link sub-model corresponding to any sub-model in the information network element layer; The network element layer is used to represent the network element sub-model corresponding to any communication link sub-model in the communication link layer; the network element sub-model is used to indicate the communication network elements included in the corresponding communication link.

2. The static model according to claim 1, characterized in that The measuring element unit is used to obtain the required physical quantity and convert it into the input of the information network; the information transmission path unit is used to transmit various types of data; the information calculation and processing unit is used to generate control instructions of the system based on the set logic; the execution element unit is used to convert the control instructions carried by the information network information into actual physical quantities.

3. The static model according to claim 2, characterized in that: The static model building method comprises: Firstly, based on the coupling relationship between information and physical system, the information network component layer is constructed, which includes: physical quantity acquisition link, transmission path link, calculation and analysis link, downlink path link and instruction execution link. The information network component layer also establishes the information processing process function carried by each link respectively; secondly, based on the virtual channel of the power grid communication system, the communication link layer is established, including: the link model carrying information, the primary and backup routes and the link status; finally, based on the physical component model of the communication network, it is associated with the communication link.

4. The static model according to claim 3, characterized in that The construction of the information network element layer includes: 1) Construct the measurement component sub-model; For any measuring element n m , whose input is the state of the physical grid Output is the collection of system status F m It represents the measurement matrix, which represents the mapping of the actual signal after the acquisition process; The sub-model expression corresponding to the measurement element is as follows: 2) Construct the actuator sub-model; For any execution node n a , whose input is the control instruction of the upper branch Output is the receiving instruction of the actuator F a represents the execution matrix, which represents the mapping of control signals through the execution process; The sub-model expression corresponding to the execution node is as follows: 3) Construct the information transmission pathway sub-model; For any information transmission path T k , respectively, using column vectors and Represents the data of its input node and output node, then the information transmission path sub-model expression is as follows: In the formula, the matrix M k is a square matrix, whose order is the same as the vector and same; 4) Construct information computing and processing units; For any business, use column vector and The expressions representing the data, information calculation and processing units of its input nodes and output nodes are as follows: In the formula, F c Represents the mapping function corresponding to this link.

5. The static model according to claim 4, characterized in that Also includes: When the measured signal is collected without error, F m The element of F is 1; when the control signal is executed without error, a The element of M is 1; when the information transmission path is not disturbed, k is an identity matrix.

6. The static model according to claim 5, characterized in that The establishing of the communication link layer comprises: 1) Construct a data link set associated with information elements; The communication link layer is a collection of different data links from the start information element to the end information element, expressed as follows: Among them, Lk ij represents the set of communication links from information element i to information element j, represents the kth communication link from information element i to information element j, k = 1, 2, ..., N, and there are N communication link paths in the set; 2) Obtain the status of the communication link; For each communication link Establish their state bits respectively l and status flag P l , where State l =0, when interrupted, State l =-1, State when bit error occurs l =1.

7. The static model according to claim 6, characterized in that Also includes: When State l =1, the bit error rate of the communication link is recorded.

8. The static model according to claim 7, characterized in that The physical component model based on the communication network is associated with the communication link, including: 1) For any communication link Let the associated set be: in, is the mth communication channel of the communication link k between information element i and information element j, and M is the total number of communication channels; 2) Obtain the status of the communication channel; For any communication channel Get its state bit State c and status flag P c , where State c =0, when interrupted, State c =-1, State when bit error occurs c =1.

9. The static model according to claim 8, characterized in that Also includes: When State c =1, the bit error rate of the channel is recorded.

10. A fault analysis method based on the static model as claimed in claim 9, characterized in that: include: 1) Establish the propagation path of the impact of component failure at each level; For any communication channel Its abnormal state According to the communication channel and communication link association, the communication link between communication elements i and j Status The calculation expression is as follows: Where η m,k is the influence weight of the mth communication network element on the kth path; The fault impact is propagated to the information network element layer in a weighted manner according to the status of the communication link, namely: In the formula, ζ k is the kth path pair LK ij The weight of influence; 2) Analysis of the impact of information components on automatic control systems; For any information element LK ij ,The impact of its on the automatic control system is based on the ,information-physical coupling model.,First, the impact of the abnormal information component on the ,information volume on which it carries is analyzed, and then the impact of the information volume on the ,key physical indicators of the physical system is analyzed: Among them, λ p is the set physical quantity, s c is the amount of information in the automatic control system; f is the fault impact equation of information-physical coupling, which is the product of the sensitivity of information elements to information flow and the sensitivity of information flow to physical quantity.

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