Method and device for modeling operation risk of intelligent substation protection based on distributed petri net

Abstract

The application discloses a kind of based on distribution Petri net's intelligent substation protection operation risk's modeling method and device, it includes the association matrix of the Petri net transition and library of each protection is constructed;The relevant pressboard is added to the input library of the relevant transition of each protection of Petri net that has been constructed as library;Coupling relationship library, coupling state library are constructed to the information transmission between each protection;The input library state of protection of Petri net is set, respectively deduces and analyzes each stage of protection of Petri net, according to coupling relationship library, using the state value of the output library of protection of Petri net updates coupling state library, to assign value to the state value of the relevant input library of subsequent protection of Petri net, start subsequent protection of Petri net;If the protection action corresponding to primary equipment failure is not completed, then the Petri net of this protection occurs blockage.The application can obtain the specific reason of protection operation in a certain link occurs blockage, obtains the risk point position of protection.

Description

Technical Field

[0001] This invention relates to the field of active distribution network line protection technology, and in particular to a modeling method and apparatus for the operational risk of smart substation protection based on distributed Petri nets. Background Technology

[0002] In recent years, with the expansion of the power grid, smart substations have been developed vigorously. However, the addition of merging units and intelligent terminals to substations, communication networks between various protection devices, and the use of soft pressure plates to control protection behavior have made the operation of these devices more complex, impacting the reliable operation of the substation.

[0003] To better depict the operational processes of various protection devices in intelligent substations, Reference 1 constructs a visualized SCD (Substation Configuration Description) file management system based on the IEC 61850 standard. This visualized SCD module provides a more detailed understanding of the transmission of GOOSE and SV information between protection devices, merging units, and intelligent terminals within the intelligent substation.

[0004] Reference 2 relies on the online monitoring and fault diagnosis functions of GOOSE (Generic Object Oriented Substation Event) loops in smart substations. Taking GOOSE loops in line bays and bus bays as examples, it studies a Petri net modeling method for GOOSE loops in different bays. Finally, using a GOOSE link break in a line bay as an example, it uses the Petri net of the GOOSE loop for fault diagnosis to locate the fault point. The limitation of this reference is that it only considers GOOSE link break as a single fault cause, which has its limitations.

[0005] Reference 3 establishes an information flow Petri net for line protection, placing all devices within a single Petri net. This demonstrates the complete process of a line protection device cooperating with bus protection, intelligent terminals, and protection and testing equipment to complete protection actions and trip. However, this reference does not depict abnormal actions of each protection device, such as operation after receiving a failure signal, or whether the bus protection can operate normally under bus fault conditions or under certain sampled signal conditions. When a pressure plate (value, sampled value) is not activated, differential current is generated, causing malfunction. This paper uses a Petri subnet to represent the status values ​​of all soft pressure plates, control words, and alarms of the equipment, replacing the status values ​​of the "protection function is activated and normal" section in the line Petri net diagram. This reflects the effect of these factors on activating or blocking the protection function. However, the various soft / hard pressure plates of the equipment, including function pressure plates, SV receiving pressure plates, GOOSE receiving / exit pressure plates, and maintenance pressure plates, play different roles in equipment self-testing, receiving SV, receiving GOOSE, and sending trip and failure GOOSE messages. Using only the "protection function is activated and normal" section cannot reflect the respective roles of these soft / hard pressure plates at different stages.

[0006] The methods mentioned above each have their shortcomings. They do not consider the role and influence of the pressure plate on the protection operation, do not establish Petri nets for each protection separately, and do not consider the coupling relationship and the transmission of status information between the Petri nets of each protection.

[0007] References:

[0008] Reference 1: Liu Hongjun, Gao Xu, Du Liyan, Yu Junjie. Modular design of SCD file management system for intelligent substation [J]. Power System Protection and Control, 2019, 47(3): 154-159.

[0009] Reference 2: Zhou Hongyang, Huang Jiayin, Zhang Chi, Ding Xiaobing, Luo Kun, Zhang Zhiqiang, Wu Fangying, Xu Jiayan. Fault diagnosis of GOOSE loop in smart substation based on Petri net [J]. Southern Power Grid Technology, 2017, 11(6): 49-56;

[0010] Reference 3: Chen Jun, Liu Xin, Wang Liping, Zheng Zhong, Ye Xiang, Ren Jie. Research on fault diagnosis and location method of protection and control of Petri net smart substation [J]. China Measurement & Testing, 2019, 45(10): 128-134. Summary of the Invention

[0011] In view of this, the present invention provides a modeling method and device for the operational risk of intelligent substation protection based on distributed Petri nets, which realizes the deduction and analysis of the operational behavior of each protection under the action of soft / hard pressure plates, and realizes the checking of the completion of protection actions, and the analysis and finding the specific reasons for the blockage of protection actions at which stage.

[0012] This invention discloses a modeling method for the protection operation risk of smart substations based on distributed Petri nets, which includes:

[0013] Based on the working principle of the protection corresponding to each primary device in the smart substation, Petri net technology is used to construct the Petri net for each protection. Based on the structure of the Petri net for each protection, the corresponding transition and storage correlation matrix is ​​constructed.

[0014] Using the pressure plate configuration of each protection device in the SCD file, the relevant pressure plates are added as input places to the relevant transitions of the Petri net of each constructed protection. The relevant pressure plates include functional pressure plates, SV receiving pressure plates, and maintenance pressure plates.

[0015] Based on the virtual loop connection information of each protection device in the SCD file, a coupling relationship library for information transmission between each protection is constructed to describe the coupling relationship between the output library of a protection’s Petri net and the input library of the Petri net of related protections. A coupling state library is also constructed to store the state information transmitted by each primary device’s dual protection to related protections based on the coupling relationship structure.

[0016] The state of the input sites of the Petri net for this protection is set, the Petri net for this protection is invoked, and each stage of the Petri net for this protection is deduced and analyzed based on the correlation matrix. According to the coupling relationship library, the state value of the output sites of the Petri net for this protection is used to update the coupling state library so as to assign the state value of the relevant input sites of the Petri net for subsequent protection, and the Petri net for subsequent protection is started. If the protection action corresponding to a primary equipment fault is not completed, the Petri net for this protection is blocked.

[0017] Furthermore, based on the working principle of the protection corresponding to each primary device in the intelligent substation, Petri net technology is used to construct the Petri net for each protection. Based on the structure of the Petri net for each protection, the corresponding transition and location correlation matrix is ​​constructed, including:

[0018] Step 11: For a smart substation, construct corresponding Petri networks for the normal operation and blocking status of line protection on the high-voltage side, medium-voltage side, and low-voltage side respectively; for the bus, establish a Petri network for bus protection; establish Petri networks for the protection of each circuit breaker; establish Petri networks for the normal operation of the main transformer protection and Petri networks for the failure tripping of the main transformer protection.

[0019] Step 12: Based on all the protected Petri net structures obtained in Step 11, construct the corresponding transition-place correlation matrix. W This is used to represent the connection relationship between each change and each repository.

[0020] Further, step 12 includes:

[0021] In the association matrix, the element corresponding to an input library and its pointed-to transition is -1; the element corresponding to a transition and its output library is 1; if a library is not associated with any other transition, the element corresponding to that library and that other transition in the association matrix is ​​0; the association matrix... W Each element in the code is defined as follows:

[0022] (2)

[0023] In the formula, Represented as from change t to the warehouse p The directed arc, Indicated as a warehouse p To change t A directed arc;

[0024] When a place is the input place for multiple transitions, the state of that place can only trigger one transition. To address this, all subsequent transitions from that place are weighted, allowing the place to trigger multiple subsequent transitions simultaneously in a single iteration. The weights are represented as follows:

[0025] (5)

[0026] In the formula, Represented as a directed arc The weight of the library; k When the input library is a change, then The value is 1 / k .

[0027] Furthermore, the step of using the pressure plate configuration of each protection device in the SCD file to add the relevant pressure plates as input places to the relevant transitions of the constructed Petri net of each protection includes:

[0028] In the Petri net corresponding to each primary device, the sampled value (SV) information of the merging unit is uploaded to the protection device. After receiving the SV information, the protection device issues a trip command and a failure signal. The trip command is transmitted to the intelligent terminal, and the failure signal is transmitted to the adjacent protection device. In the protection Petri net, the corresponding SV receiving pressure plate is used as a condition for uploading the merging unit information, i.e., an input location, to complete the triggering of the first round of transitions. The function pressure plate and the maintenance pressure plate are used as conditions for the protection device to operate, and together with the uploading of the merging unit information, they trigger the second round of transitions. The triggering of the third round of transitions requires that the trip command, the failure signal, and the corresponding GOOSE sending soft pressure plate be in the activated state.

[0029] Furthermore, the step of using the pressure plate configuration of each protection device in the SCD file to add the relevant pressure plates as input places to the relevant transitions of the constructed Petri net of each protection specifically includes:

[0030] For the Petri network protecting 500kV lines, in its "SV Reception" transition, two circuit breaker 5021 SV receiving pressure plates, 5022 SV receiving pressure plates, and a line SV receiving pressure plate are added as input locations. In the "Protection Function Trigger" transition, protection function pressure plates and maintenance pressure plates are added as input locations. Among them, the maintenance pressure plate location has an arc suppression function, meaning it can only participate in the triggering of this transition when its state value is 0. In the "Send 5021 Trip Command to Smart Terminal" and "Send 5022 Trip Command to Smart Terminal" transitions... In the transition of the "terminal", 5021 trip output pressure plate and 5022 trip output pressure plate are added respectively as their input locations; in the transition of "send 5021 failure signal output" and "send 5022 failure signal output", 5021 failure start pressure plate and 5022 failure start pressure plate are added respectively as their input locations; in this way, corresponding pressure plates are set in each link of the protection, including SV reception, protection action, trip signal transmission, and failure GOOSE signal start, so as to express the different roles of each pressure plate in the 500kV line protection action;

[0031] The addition of pressure plates in Petri networks for busbar protection, transformer protection, and circuit breaker protection is similar to the addition of pressure plates in Petri networks for 500kV line protection.

[0032] Furthermore, based on the virtual loop connection information of each protection device in the SCD file, a coupling relationship library for information transmission between protections is constructed to describe the coupling relationship between the output library of a protection's Petri net and the input library of a related protection's Petri net. A coupling state library is also constructed to store the state information transmitted by each primary device's dual-set protection based on the coupling relationship structure to the related protections, including:

[0033] Parse the virtual loop connection information of each protection device from the SCD file, that is, the trip GOOSE message sent by a protection device to the smart terminal and the start failure GOOSE message sent to other related protections. Construct a coupling relationship structure to describe the coupling relationship between the output place of a protection Petri net and the input place of related protection Petri nets.

[0034] Based on the virtual loop connection information of each protection output, construct the corresponding coupling relationship structure, and then add them to the coupling relationship structure array to form a coupling relationship library;

[0035] A coupled state library is constructed to store the state information transmitted by the dual protection of each primary device based on the coupling relationship structure. The dual protection is set A protection and set B protection. For each coupling relationship structure, there is a corresponding row in the coupled state library. The first and second columns of the row store the state values ​​of the output library corresponding to set A protection and set B protection in the coupling relationship structure, respectively.

[0036] Further, the state of the input sites of the Petri net for protection is set, the Petri net for protection is invoked, and based on the correlation matrix, each stage of the Petri net for protection is deduced and analyzed. According to the coupling relationship library, the state value of the output sites of the Petri net for protection is used to update the coupling state library, so as to assign the state value of the relevant input sites of the Petri net for subsequent protection, and start the Petri net for subsequent protection; if the protection action corresponding to a primary equipment fault is not completed, the Petri net for protection is blocked, including:

[0037] When a primary device malfunctions, the activation / deactivation status of each pressure plate in the Petri net corresponding to that primary device is set, the initial state of the Petri net of the corresponding protection is updated, and the operation of each stage of the Petri net of the protection is simulated; after the Petri net of the protection has finished operating, the transition cumulative trigger vector of the Petri net corresponding to the protection is obtained; and the protection action corresponding to the primary device is analyzed to see if it has been completed.

[0038] If the protection action is not completed, the transition accumulation trigger vector is used to find the untriggered transitions in the Petri net of the protection. Each input place of the transition is checked in turn. If the state value of an input place without a suppression arc is 0, it is determined that the transition was not triggered due to this input place, which causes the protection action corresponding to the Petri net to fail to complete, i.e., the Petri net is blocked. Then, using the coupling relation library, the Petri net of the subsequent protection related to the current Petri net is found. The state value of the output place of the current Petri net is assigned to the state value of the relevant input place of the Petri net of the subsequent protection, and the initial state of the Petri net of the subsequent protection is updated so that the Petri net of the subsequent protection can be started.

[0039] Furthermore, the Petri net of the protection is invoked, and based on the correlation matrix, each stage of the Petri net of the protection is deduced and analyzed, including:

[0040] Step 401: Set the on / off status of each pressure plate in the Petri net corresponding to the primary equipment in case of a fault, and set the storage status vector of the Petri net corresponding to the primary equipment. M Configure settings;

[0041] Step 402: Based on the place state vectors of each transition M The system determines whether each transition meets the triggering conditions, performs behavior extrapolation for the current Petri net under protection, and calculates the transition trigger vector for this round. X ;

[0042] Step 403: If the transition trigger vector X If there is a non-zero value, indicating that a new transition has been triggered, then the correlation matrix is ​​used. W The storage status vector for this round Transition trigger vector X The state vector of the storage area after this round of simulation is calculated. Repeat step 402; when the transition triggers the vector X If all values ​​in the middle are 0, meaning no new transitions are triggered, then the state vector of the place after this round of deduction is... The final state value of the repository is given, marking the end of this Petri net simulation. It is a positive integer;

[0043] Step 404: After the Petri net simulation for the current protection is completed, the transition trigger vectors for each round are... X The elements in each column are summed to obtain the cumulative transition trigger vector of the Petri net. According to vectors Check whether the various transitions of the trip command and failure signal that the protection needs to issue have been triggered. If all transitions have been triggered, the protection action is completed; otherwise, the protection action is not completed.

[0044] Step 405: Using the coupling relationship library, find the Petri nets of each subsequent protection related to the current Petri net, store the state value of the output library of the current Petri net into the coupling state library, and assign it to the state value of the input library of the subsequent Petri net, so that the Petri nets of each subsequent protection can receive the state value sent by the superior and be started and perform deduction.

[0045] Step 406: For other protections in the smart substation, repeat steps 402 to 405 to realize the deduction and analysis of the Petri net for each protection and transmit instructions to the Petri net of the relevant protection.

[0046] Further, step 401 includes:

[0047] If a pressure plate is engaged, the status value of the corresponding pressure plate storage area is set to 1; the Petri net of the protection corresponding to the primary fault device is used as the Petri net of the current protection; based on the storage area status vector required by the Petri net of the protection corresponding to the primary device and the engagement / disengagement status of a single pressure plate, the storage area status vector of the Petri net is set. M Initial state vector M 0.

[0048] Further, step 402 includes:

[0049] If the first one does not contain the suppressor arc The first change, then the second Triggering state of each transition The calculation is as follows:

[0050] (3)

[0051] In the formula, n Indicates the first The number of input locations for each transition; It is the first n The status values ​​of each input library; It is a transition trigger vector X The first in One element;

[0052] The first arc can only be triggered when the state values ​​of all input libraries without suppression arcs are greater than 0. A transition, a transition trigger vector X The corresponding number in The value of the nth element is 1; otherwise, it is 0, i.e., the nth element is 0. One cannot be triggered;

[0053] If a transition involves an input place with a suppression arc, the transition can only be triggered if the state values ​​of all input places without suppression arcs are greater than 0, while the state values ​​of input places with suppression arcs are all less than 0. The first change, the Triggering state of each transition The calculation is as follows:

[0054] (4)

[0055] In the formula, For the first n The state value of an input library without a suppression arc. For the first k The state value of an input library containing a suppression arc. It is the number of the input location containing the suppression arc; It is a transition trigger vector X The first in One element;

[0056] When a place is the input place of multiple transitions, assuming the initial state value of the place is 1, after a transition pointed to by the output of the place is triggered, through the derivation of the transition, the state value of the place becomes 1-1 / k. Since the state value of the place is still greater than 0, other transitions can continue to be triggered.

[0057] Step 403 includes:

[0058] No. j The formula for calculating the state vector of a storage location in a given round is:

[0059] (6)

[0060] In the formula, For the first State vectors of each warehouse before the round of simulation; For the first The state vectors of each depot after round of simulation; Transition trigger vector; This is the correlation matrix between locations and changes.

[0061] Furthermore, after step 404 and before step 405, the procedure further includes:

[0062] If the protection action is completed, proceed to step 405, utilizing the final... Update the coupling state library; if the protection action is not completed, find the abnormal transition and the reason why the abnormal transition was not triggered; accumulate the trigger vector based on the transition. If the value of an element is 0, find the untriggered transition in the Petri net; first, judge the transition. If the parent transition of the untriggered transition is also not triggered, then there is no need to check the input library of the current transition; if a parallel transition of the current transition has been triggered, then there is no need to check the input library of the current transition.

[0063] For transitions that are not triggered after screening, check the status values ​​of each input location of the transition in sequence. If the status value of an input location without a suppression arc is 0, it means that the input location is abnormal. If the status value of an input location with a suppression arc is 1, it is determined that the input location is abnormal. The abnormal location is the reason why the protection of the primary device is blocked in this transition, thereby discovering the possible risk location of the protection, which helps to find the risk point of the protection.

[0064] Furthermore, the structure of the protected Petri net is represented as follows:

[0065] (1)

[0066] In the formula, Describes a finite set of places. A finite set representing change. F This represents the set of directed arcs between places and transitions; Indicates a suppression arc, X This represents the transition trigger vector. W The relation matrix representing places and changes. M This is the state vector of the place in the Petri net.

[0067] This invention also discloses a modeling device for the protection operation risk of smart substations based on distributed Petri nets, comprising:

[0068] The first construction module is used to construct the Petri net of each protection according to the working principle of the protection corresponding to each primary equipment in the smart substation, using Petri net technology, and construct the corresponding transition and storage association matrix according to the structure of the Petri net of each protection.

[0069] The module adds relevant pressure plates as input spaces to the relevant transition spaces of the Petri net of each protection device using the pressure plate configuration of each protection device in the SCD file; the relevant pressure plates include functional pressure plates, SV receiving pressure plates and maintenance pressure plates;

[0070] The second construction module is used to construct a coupling relationship library for information transmission between protections based on the virtual loop connection information of each protection device in the SCD file. It is used to describe the coupling relationship between the output library of a protection’s Petri net and the input library of the Petri net of related protections, and to construct a coupling state library to store the state information transmitted by each primary device’s dual protection based on the coupling relationship structure to related protections.

[0071] The blocking module is used to set the input state of the Petri net for this protection, call the Petri net for this protection, and perform deduction and analysis of each stage of the Petri net for this protection based on the correlation matrix. According to the coupling relationship library, the state value of the output state of the Petri net for this protection is used to update the coupling state library so as to assign the state value of the relevant input state of the Petri net for subsequent protection, and start the Petri net for subsequent protection. If the protection action corresponding to a primary equipment fault is not completed, the Petri net for this protection will be blocked.

[0072] Furthermore, based on the working principle of the protection corresponding to each primary device in the intelligent substation, Petri net technology is used to construct the Petri net for each protection. Based on the structure of the Petri net for each protection, the corresponding transition and location correlation matrix is ​​constructed, including:

[0073] The Petri network creation module is used to construct corresponding Petri networks for a smart substation, specifically for the normal operation and blocking status of line protection on the high-voltage side, medium-voltage side, and low-voltage side; for the busbar, it creates Petri networks for busbar protection; it creates Petri networks for the protection of each circuit breaker; and it creates Petri networks for the normal operation of the main transformer protection and Petri networks for the failure tripping of the main transformer protection.

[0074] The correlation matrix construction module is used to construct the corresponding correlation matrix between transitions and places based on the structure of all protected Petri nets obtained from the Petri net construction module. W Correlation matrix W Used to represent the connection relationship between each change and each repository.

[0075] Furthermore, the correlation matrix construction module is used for:

[0076] In the association matrix, the element corresponding to an input library and its pointed-to transition is -1; the element corresponding to a transition and its output library is 1; if a library is not associated with any other transition, the element corresponding to that library and that other transition in the association matrix is ​​0; the association matrix... W Each element in the code is defined as follows:

[0077] (2)

[0078] In the formula, Represented as from change t to the warehouse p The directed arc, Indicated as a warehouse p To change t A directed arc;

[0079] When a place is the input place for multiple transitions, the state of that place can only trigger one transition. To address this, all subsequent transitions from that place are weighted, allowing the place to trigger multiple subsequent transitions simultaneously in a single iteration. The weights are represented as follows:

[0080] (5)

[0081] In the formula, Represented as a directed arc The weight of the library; k When the input library is a change, then The value is 1 / k .

[0082] Furthermore, the adding module is used for:

[0083] In the Petri net corresponding to each primary device, the sampled value (SV) information of the merging unit is uploaded to the protection device. After receiving the SV information, the protection device issues a trip command and a failure signal. The trip command is transmitted to the intelligent terminal, and the failure signal is transmitted to the adjacent protection device. In the protection Petri net, the corresponding SV receiving pressure plate is used as a condition for uploading the merging unit information, i.e., an input location, to complete the triggering of the first round of transitions. The function pressure plate and the maintenance pressure plate are used as conditions for the protection device to operate, and together with the uploading of the merging unit information, they trigger the second round of transitions. The triggering of the third round of transitions requires that the trip command, the failure signal, and the corresponding GOOSE sending soft pressure plate be in the activated state.

[0084] Furthermore, the added module is specifically used for:

[0085] For the Petri network protecting 500kV lines, in its "SV Reception" transition, two circuit breaker 5021 SV receiving pressure plates, 5022 SV receiving pressure plates, and a line SV receiving pressure plate are added as input locations. In the "Protection Function Trigger" transition, protection function pressure plates and maintenance pressure plates are added as input locations. Among them, the maintenance pressure plate location has an arc suppression function, meaning it can only participate in the triggering of this transition when its state value is 0. In the "Send 5021 Trip Command to Smart Terminal" and "Send 5022 Trip Command to Smart Terminal" transitions... In the transition of the "terminal", 5021 trip output pressure plate and 5022 trip output pressure plate are added respectively as their input locations; in the transition of "send 5021 failure signal output" and "send 5022 failure signal output", 5021 failure start pressure plate and 5022 failure start pressure plate are added respectively as their input locations; in this way, corresponding pressure plates are set in each link of the protection, including SV reception, protection action, trip signal transmission, and failure GOOSE signal start, so as to express the different roles of each pressure plate in the 500kV line protection action;

[0086] The addition of pressure plates in Petri networks for busbar protection, transformer protection, and circuit breaker protection is similar to the addition of pressure plates in Petri networks for 500kV line protection.

[0087] Furthermore, the second construction module is used for:

[0088] Parse the virtual loop connection information of each protection device from the SCD file, that is, the trip GOOSE message sent by a protection device to the smart terminal and the start failure GOOSE message sent to other related protections. Construct a coupling relationship structure to describe the coupling relationship between the output place of a protection Petri net and the input place of related protection Petri nets.

[0089] Based on the virtual loop connection information of each protection output, construct the corresponding coupling relationship structure, and then add them to the coupling relationship structure array to form a coupling relationship library;

[0090] A coupled state library is constructed to store the state information transmitted by the dual protection of each primary device based on the coupling relationship structure. The dual protection is set A protection and set B protection. For each coupling relationship structure, there is a corresponding row in the coupled state library. The first and second columns of the row store the state values ​​of the output library corresponding to set A protection and set B protection in the coupling relationship structure, respectively.

[0091] Furthermore, the blocking generation module is used for:

[0092] When a primary device malfunctions, the activation / deactivation status of each pressure plate in the Petri net corresponding to that primary device is set, the initial state of the Petri net of the corresponding protection is updated, and the operation of each stage of the Petri net of the protection is simulated; after the Petri net of the protection has finished operating, the transition cumulative trigger vector of the Petri net corresponding to the protection is obtained; and the protection action corresponding to the primary device is analyzed to see if it has been completed.

[0093] If the protection action is not completed, the transition accumulation trigger vector is used to find the untriggered transitions in the Petri net of the protection. Each input place of the transition is checked in turn. If the state value of an input place without a suppression arc is 0, it is determined that the transition was not triggered due to this input place, which causes the protection action corresponding to the Petri net to fail to complete, i.e., the Petri net is blocked. Then, using the coupling relation library, the Petri net of the subsequent protection related to the current Petri net is found. The state value of the output place of the current Petri net is assigned to the state value of the relevant input place of the Petri net of the subsequent protection, and the initial state of the Petri net of the subsequent protection is updated so that the Petri net of the subsequent protection can be started.

[0094] Furthermore, the blocking module includes a deduction and analysis unit; the deduction and analysis unit is used to invoke the Petri net of the protection and, based on the correlation matrix, perform deduction and analysis on each stage of the Petri net of the protection.

[0095] Furthermore, the deduction and analysis unit includes:

[0096] The configuration subunit is used to set the on / off status of each pressure plate in the Petri net corresponding to the primary equipment when a fault occurs, and to set the storage status vector of the Petri net corresponding to the primary equipment. M Configure settings;

[0097] The calculation sub-unit is used to calculate the place state vectors for each transition. M The system determines whether each transition meets the triggering conditions, performs behavior extrapolation for the current Petri net under protection, and calculates the transition trigger vector for this round. X ;

[0098] Inference subunit, used for transition trigger vector X If there is a non-zero value, indicating that a new transition has been triggered, then the correlation matrix is ​​used. W The storage status vector for this round Transition trigger vector X The state vector of the storage area after this round of simulation is calculated. Repeatedly execute the computation sub-unit; when the transition triggers the vector XIf all values ​​in the middle are 0, meaning no new transitions are triggered, then the state vector of the place after this round of deduction is... The final state value of the repository is given, marking the end of this Petri net simulation. It is a positive integer;

[0099] The inspection sub-unit is used to check the transition trigger vectors of each round after the current Petri net run simulation is completed. X The elements in each column are summed to obtain the cumulative transition trigger vector of the Petri net. According to vectors Check whether the various transitions of the trip command and failure signal that the protection needs to issue have been triggered. If all transitions have been triggered, the protection action is completed; otherwise, the protection action is not completed.

[0100] The assignment sub-unit is used to find the Petri nets of subsequent protections related to the Petri net of the current protection using the coupling relationship library, store the state value of the output library of the current Petri net into the coupling state library, and assign it to the state value of the input library of the subsequent Petri net so that the Petri nets of subsequent protections can receive the state value sent by the superior and be started and perform deduction.

[0101] The iterative subunit is used to repeatedly call the calculation subunit, deduction subunit, check subunit, and assignment subunit for other protections in the smart substation. This allows for the deduction and analysis of the Petri net for each protection, and the transmission of instructions to the Petri net of the relevant protection.

[0102] Furthermore, the setting subunit is used for:

[0103] If a pressure plate is engaged, the status value of the corresponding pressure plate storage area is set to 1; the Petri net of the protection corresponding to the primary fault device is used as the Petri net of the current protection; based on the storage area status vector required by the Petri net of the protection corresponding to the primary device and the engagement / disengagement status of a single pressure plate, the storage area status vector of the Petri net is set. M Initial state vector M 0.

[0104] Furthermore, the computing subunit is used for:

[0105] If the first one does not contain the suppressor arc The first change, then the second Triggering state of each transition The calculation is as follows:

[0106] (3)

[0107] In the formula, n Indicates the first The number of input locations for each transition; It is the first n The status values ​​of each input library; It is a transition trigger vector X The first in One element;

[0108] The first arc can only be triggered when the state values ​​of all input libraries without suppression arcs are greater than 0. A transition, a transition trigger vector X The corresponding number in The value of the nth element is 1; otherwise, it is 0, i.e., the nth element is 0. One cannot be triggered;

[0109] If a transition involves an input place with a suppression arc, the transition can only be triggered if the state values ​​of all input places without suppression arcs are greater than 0, while the state values ​​of input places with suppression arcs are all less than 0. The first change, the Triggering state of each transition The calculation is as follows:

[0110] (4)

[0111] In the formula, For the first n The state value of an input library without a suppression arc. For the first k The state value of an input library containing a suppression arc. It is the number of the input location containing the suppression arc; It is a transition trigger vector X The first in One element;

[0112] When a place is the input place of multiple transitions, assuming the initial state value of the place is 1, after a transition pointed to by the output of the place is triggered, through the derivation of the transition, the state value of the place becomes 1-1 / k. Since the state value of the place is still greater than 0, other transitions can continue to be triggered.

[0113] The deduction subunit is used for:

[0114] No. j The formula for calculating the state vector of a storage location in a given round is:

[0115] (6)

[0116] In the formula, For the first State vectors of each warehouse before the round of simulation; For the first The state vectors of each depot after round of simulation; Transition trigger vector; This is the correlation matrix between locations and changes.

[0117] Furthermore, a risk point identification unit is provided between the inspection subunit and the assignment subunit, the risk point identification unit being used for:

[0118] If the protection action is completed, then proceed to the assignment sub-unit and utilize the final... Update the coupling state library; if the protection action is not completed, find the abnormal transition and the reason why the abnormal transition was not triggered; accumulate the trigger vector based on the transition. If the value of an element is 0, find the untriggered transition in the Petri net; first, judge the transition. If the parent transition of the untriggered transition is also not triggered, then there is no need to check the input library of the current transition; if a parallel transition of the current transition has been triggered, then there is no need to check the input library of the current transition.

[0119] For transitions that are not triggered after screening, check the status values ​​of each input location of the transition in sequence. If the status value of an input location without a suppression arc is 0, it means that the input location is abnormal. If the status value of an input location with a suppression arc is 1, it is determined that the input location is abnormal. The abnormal location is the reason why the protection of the primary device is blocked in this transition, thereby discovering the possible risk location of the protection, which helps to find the risk point of the protection.

[0120] Furthermore, the structure of the protected Petri net is represented as follows:

[0121] (1)

[0122] In the formula, Describes a finite set of places. A finite set representing change. F This represents the set of directed arcs between places and transitions; Indicates a suppression arc, X This represents the transition trigger vector. W The relation matrix representing places and changes. M This is the state vector of the place in the Petri net.

[0123] Because of the adoption of the above technical solution, the present invention has the following advantages:

[0124] 1. Based on the SCD virtual loop soft pressure board information and protection configuration principle, this invention adds soft / hard pressure boards to each link of the Petri net, intuitively showing the functions of different soft pressure boards such as SV receiving soft pressure board, GOOSE output soft pressure board, various functional soft pressure boards, and maintenance hard pressure board in each protection action.

[0125] 2. In the intelligent substation of this invention, virtual loops transmit GOOSE signals such as tripping and failure between protections. Distributed Petri nets represent the protection action logic of the primary equipment. In order to transmit the transition information of the protection to adjacent protections, a coupling relationship library and a coupling state library are set up, which respectively store the information transmission relationship between protections and the specific transmitted state information. The distributed Petri nets are connected in series through the coupling relationship library. Through the transmitted state information, the subsequent Petri nets are activated.

[0126] 3. This invention determines whether the distributed Petri net is running completely based on the cumulative trigger vector of the transition. If it is not running completely, it is necessary to provide the untriggered transitions and their abnormal locations, so as to find the cause of the failure of a certain transition being blocked.

[0127] 4. This invention proposes a modeling method for the protection operation risk of smart substations based on distributed Petri nets. Considering the role of pressure plates, it can accurately model the protection operation behavior of smart substations. It is applicable to 500kV and 220kV smart substations and can realize the modeling and process analysis of the action behavior of various protection devices in smart substations with high accuracy. Attached Figure Description

[0128] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments recorded in the embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0129] Figure 1 This is a flowchart of the modeling method for the protection operation risk of smart substations based on distributed Petri nets proposed in this invention;

[0130] Figure 2 This is the main wiring diagram of the 500kV intelligent substation mentioned in Embodiment 1 of the present invention;

[0131] Figure 3 Petri net diagram for normal operation of 500kV line protection. Detailed Implementation

[0132] The present invention will be further described in conjunction with the accompanying drawings and embodiments. The described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art should fall within the protection scope of the present invention.

[0133] Because existing technologies do not consider the role and impact of pressure plates on protection operations, do not establish separate Petri nets for each protection, and do not consider the coupling relationships between Petri nets, it is necessary to establish separate Petri nets for each protection. It is also necessary to add the corresponding locations of pressure plates to each stage of the Petri net, and to establish the coupling relationships between the relevant output locations of each Petri net and the input locations of other Petri nets based on the virtual loops between protections in the SCD. This allows for information flow between the Petri nets of the distributed protection systems, enabling multiple Petri net calculations for each behavior during the protection operation process. For this purpose, see [link to relevant documentation]. Figure 1 This invention proposes an embodiment of a modeling method for the protection operation risk of smart substations based on distributed Petri nets, which includes:

[0134] Based on the working principle of the protection corresponding to each primary device in the smart substation, Petri net technology is used to construct the Petri net for each protection. Based on the structure of the Petri net for each protection, the corresponding transition and storage correlation matrix is ​​constructed.

[0135] Using the pressure plate configuration of each protection device in the SCD file, the relevant pressure plates are added as input places to the relevant transitions of the Petri net of each constructed protection. The relevant pressure plates include functional pressure plates, SV receiving pressure plates, and maintenance pressure plates.

[0136] Based on the virtual loop connection information of each protection device in the SCD file, a coupling relationship library for information transmission between each protection is constructed to describe the coupling relationship between the output library of a protection’s Petri net and the input library of the Petri net of related protections. A coupling state library is also constructed to store the state information transmitted by each primary device’s dual protection to related protections based on the coupling relationship structure.

[0137] When a primary device malfunctions, the activation / deactivation status of each pressure plate in the Petri net corresponding to that primary device is set. This involves setting the input state of the Petri net for that protection, calling the Petri net for that protection, and performing deduction and analysis on each stage of the Petri net based on the correlation matrix. According to the coupling relationship library, the state value of the output state of the Petri net for that protection is used to update the coupling state library so that it can be assigned to the state value of the relevant input state of the Petri net for subsequent protections, thus starting the Petri net for subsequent protections. If the protection action corresponding to the primary device malfunction is not completed, the Petri net for that protection will be blocked.

[0138] In one embodiment of this application, the step of constructing a Petri net for each protection device based on the working principle of the protection corresponding to each primary device in the smart substation, using Petri net technology, and constructing a corresponding transition-storage correlation matrix based on the structure of the Petri net for each protection device, includes:

[0139] Step 11: For a smart substation, construct corresponding Petri networks for the normal operation and blocking status of line protection on the high-voltage side, medium-voltage side, and low-voltage side respectively; for the bus, establish a Petri network for bus protection; establish Petri networks for the protection of each circuit breaker; establish Petri networks for the normal operation of the main transformer protection and Petri networks for the failure tripping of the main transformer protection.

[0140] Step 12: Based on the structure of all the protected Petri nets obtained in Step 11, construct the corresponding transition-place correlation matrix. W This is used to represent the connection relationship between each change and each repository.

[0141] In one embodiment of this application, step 12 includes:

[0142] In the association matrix, the element corresponding to an input library and its pointed-to transition is -1; the element corresponding to a transition and its output library is 1; if a library is not associated with any other transition, the element corresponding to that library and that other transition in the association matrix is ​​0; the association matrix... W Each element in the code is defined as follows:

[0143] (2)

[0144] In the formula, Represented as from change t to the warehouse p The directed arc, Indicated as a warehouse p To change t A directed arc;

[0145] When a place is the input place for multiple transitions, the state of that place can only trigger one transition. To address this, all subsequent transitions from that place are weighted, allowing the place to trigger multiple subsequent transitions simultaneously in a single iteration. The weights are represented as follows:

[0146] (5)

[0147] In the formula, Represented as a directed arc The weight of the library; k When the input library is a change, then The value is 1 / k .

[0148] In one embodiment of this application, the step of using the pressure plate configuration of each protection device in the SCD file to add the relevant pressure plates as input places to the relevant transitions of the constructed Petri net of each protection includes:

[0149] In the Petri net corresponding to each primary device, the sampled value (SV) information of the merging unit is uploaded to the protection device. After receiving the SV information, the protection device issues a trip command and a failure signal. The trip command is transmitted to the intelligent terminal, and the failure signal is transmitted to the adjacent protection device. In the protection Petri net, the corresponding SV receiving pressure plate is used as a condition for uploading the merging unit information, i.e., an input location, to complete the triggering of the first round of transitions. The function pressure plate and the maintenance pressure plate are used as conditions for the protection device to operate, and together with the uploading of the merging unit information, they trigger the second round of transitions. The triggering of the third round of transitions requires that the trip command, the failure signal, and the corresponding GOOSE sending soft pressure plate be in the activated state.

[0150] In one embodiment of this application, the step of using the pressure plate configuration of each protection device in the SCD file to add the relevant pressure plates as input places to the relevant transitions of the constructed Petri net of each protection specifically includes:

[0151] For the Petri network protecting 500kV lines, in its "SV Reception" transition, two circuit breaker 5021 SV receiving pressure plates, 5022 SV receiving pressure plates, and a line SV receiving pressure plate are added as input locations. In the "Protection Function Trigger" transition, protection function pressure plates and maintenance pressure plates are added as input locations. Among them, the maintenance pressure plate location has an arc suppression function, meaning it can only participate in the triggering of this transition when its state value is 0. In the "Send 5021 Trip Command to Smart Terminal" and "Send 5022 Trip Command to Smart Terminal" transitions... In the transition of the "terminal", 5021 trip output pressure plate and 5022 trip output pressure plate are added respectively as their input locations; in the transition of "send 5021 failure signal output" and "send 5022 failure signal output", 5021 failure start pressure plate and 5022 failure start pressure plate are added respectively as their input locations; in this way, corresponding pressure plates are set in each link of the protection, including SV reception, protection action, trip signal transmission, and failure GOOSE signal start, so as to express the different roles of each pressure plate in the 500kV line protection action;

[0152] The addition of pressure plates in Petri networks for busbar protection, transformer protection, and circuit breaker protection is similar to the addition of pressure plates in Petri networks for 500kV line protection.

[0153] In one embodiment of this application, the step of constructing a coupling relationship library for information transmission between protections based on the virtual loop connection information of each protection device in the SCD file, used to describe the coupling relationship of the transmitted messages between the output library of a protection's Petri net and the input library of the Petri net of related protections, and constructing a coupling state library to store the state information transmitted by each primary device's dual-set protection based on the coupling relationship structure to related protections, includes:

[0154] Parse the virtual loop connection information of each protection device from the SCD file, i.e., the trip GOOSE message sent by a protection device to the smart terminal and the start / stop GOOSE message sent to other related protections. Construct a coupling relationship structure to describe the coupling relationship between the output sites of a protection's Petri net and the input sites of related protections' Petri nets; the data structure of the coupling relationship structure can be as follows:

[0155] struct {

[0156] string AC;% Sending device number

[0157] string ACtype; % Transmitter device sub-model number

[0158] string ACNUM; % The output library number of the transmitting device.

[0159] string TR;% Receiving device number

[0160] string TRtype; % Receiver device sub-model number

[0161] string TRNUM; % The input library number of the receiving device.

[0162] };

[0163] Based on the virtual loop connection information of each protection output, construct the corresponding coupling relationship structure, and then add them to the coupling relationship structure array to form a coupling relationship library;

[0164] A coupled state library is constructed to store the state information transmitted by the dual protection of each primary device based on the coupling relationship structure. The dual protection is set A protection and set B protection. For each coupling relationship structure, there is a corresponding row in the coupled state library. The first and second columns of the row store the state values ​​of the output library corresponding to set A protection and set B protection in the coupling relationship structure, respectively.

[0165] In one embodiment of this application, setting the activation / deactivation status of each pressure plate in the Petri net of the protection corresponding to the primary equipment failure involves setting the input state of the Petri net of the protection, calling the Petri net of the protection, performing deduction and analysis on each stage of the Petri net of the protection based on the correlation matrix, updating the coupling state library with the state value of the output state of the Petri net of the protection according to the coupling relationship library, so as to assign the state value of the relevant input state of the Petri net of the subsequent protection, and starting the Petri net of the subsequent protection; if the protection action corresponding to the primary equipment failure is not completed, the Petri net of the protection is blocked, including:

[0166] When a primary device malfunctions, the activation / deactivation status of each pressure plate in the Petri net corresponding to that primary device is set, the initial state of the Petri net of the corresponding protection is updated, and the operation of each stage of the Petri net of the protection is simulated; after the Petri net of the protection has finished operating, the transition cumulative trigger vector of the Petri net corresponding to the protection is obtained; and the protection action corresponding to the primary device is analyzed to see if it has been completed.

[0167] If the protection action is not completed, the transition accumulation trigger vector is used to find the untriggered transitions in the Petri net of the protection. Each input place of the transition is checked in turn. If the state value of an input place without a suppression arc is 0, it is determined that the transition was not triggered due to this input place, which causes the protection action corresponding to the Petri net to fail to complete, i.e., the Petri net is blocked. Then, using the coupling relation library, the Petri net of the subsequent protection related to the current Petri net is found. The state value of the output place of the current Petri net is assigned to the state value of the relevant input place of the Petri net of the subsequent protection, and the initial state of the Petri net of the subsequent protection is updated so that the Petri net of the subsequent protection can be started.

[0168] In one embodiment of this application, the invocation of the protected Petri net, based on the correlation matrix, involves deducing and analyzing each stage of the protected Petri net, including:

[0169] Step 401: Set the on / off status of each pressure plate in the Petri net corresponding to the primary equipment in case of a fault, and set the storage status vector of the Petri net corresponding to the primary equipment. M Configure settings;

[0170] Step 402: Based on the place state vectors of each transition M The system determines whether each transition meets the triggering conditions, performs behavior extrapolation for the current Petri net under protection, and calculates the transition trigger vector for this round. X ;

[0171] Step 403: If the transition trigger vector X If there is a non-zero value, indicating that a new transition has been triggered, then the correlation matrix is ​​used. W The storage status vector for this round Transition trigger vector X The state vector of the storage area after this round of simulation is calculated. Repeat step 402; when the transition triggers the vector X If all values ​​in the middle are 0, meaning no new transitions are triggered, then the state vector of the place after this round of deduction is... The final state value of the storage area marks the end of this Petri net simulation. It is a positive integer;

[0172] Step 404: After the Petri net simulation for the current protection is completed, the transition trigger vectors for each round are... X The elements in each column are summed to obtain the cumulative transition trigger vector of the Petri net. According to vectors Check whether the various transitions of the trip command and failure signal that the protection needs to issue have been triggered. If all transitions have been triggered, the protection action is completed; otherwise, the protection action is not completed.

[0173] Step 405: Using the coupling relationship library, find the Petri nets of each subsequent protection related to the current Petri net, store the state value of the output library of the current Petri net into the coupling state library, and assign it to the state value of the input library of the subsequent Petri net, so that the Petri nets of each subsequent protection can receive the state value sent by the superior and be started and perform deduction.

[0174] Step 406: For other protections in the smart substation, repeat steps 402 to 405 to realize the deduction and analysis of the Petri net for each protection and transmit instructions to the Petri net of the relevant protection.

[0175] In one embodiment of this application, step 401 includes:

[0176] If a pressure plate is engaged, the status value of the corresponding pressure plate storage area is set to 1; the Petri net of the protection corresponding to the primary fault device is used as the Petri net of the current protection; based on the storage area status vector required by the Petri net of the protection corresponding to the primary device and the engagement / disengagement status of a single pressure plate, the storage area status vector of the Petri net is set. M Initial state vector M 0.

[0177] In one embodiment of this application, step 402 includes:

[0178] If the first one does not contain the suppressor arc The first change, then the second Triggering state of each transition The calculation is as follows:

[0179] (3)

[0180] In the formula, n Indicates the first The number of input locations for each transition; It is the first n The status values ​​of each input library; It is a transition trigger vector X The first in One element;

[0181] The first arc can only be triggered when the state values ​​of all input libraries without suppression arcs are greater than 0. A transition, a transition trigger vector X The corresponding number in The value of the nth element is 1; otherwise, it is 0, i.e., the nth element is 0. One cannot be triggered;

[0182] If a transition involves an input place with a suppression arc, the transition can only be triggered if the state values ​​of all input places without suppression arcs are greater than 0, while the state values ​​of input places with suppression arcs are all less than 0. The first change, the Triggering state of each transition The calculation is as follows:

[0183] (4)

[0184] In the formula, For the first n The state value of an input library without a suppression arc. For the first k The state value of an input library containing a suppression arc. It is the number of the input location containing the suppression arc; It is a transition trigger vector X The first in One element;

[0185] When a place is the input place of multiple transitions, assuming the initial state value of the place is 1, after a transition pointed to by the output of the place is triggered, through the derivation of the transition, the state value of the place becomes 1-1 / k. Since the state value of the place is still greater than 0, other transitions can continue to be triggered.

[0186] Step 403 includes:

[0187] No. j The formula for calculating the state vector of a storage location in a given round is:

[0188] (6)

[0189] In the formula, For the first State vectors of each warehouse before the round of simulation; For the first The state vectors of each depot after round of simulation; Transition trigger vector; This is the correlation matrix between locations and changes.

[0190] In one embodiment of this application, after step 404 and before step 405, the method further includes:

[0191] If the protection action is completed, proceed to step 405, utilizing the final... Update the coupling state library; if the protection action is not completed, find the abnormal transition and the reason why the abnormal transition was not triggered; accumulate the trigger vector based on the transition. If the value of an element is 0, find the untriggered transition in the Petri net; first, judge the transition. If the parent transition of the untriggered transition is also not triggered, then there is no need to check the input library of the current transition; if a parallel transition of the current transition has been triggered, then there is no need to check the input library of the current transition.

[0192] For transitions that are not triggered after screening, check the status values ​​of each input location of the transition in sequence. If the status value of an input location without a suppression arc is 0, it means that the input location is abnormal. If the status value of an input location with a suppression arc is 1, it is determined that the input location is abnormal. The abnormal location is the reason why the protection of the primary device is blocked in this transition, thereby discovering the possible risk location of the protection, which helps to find the risk point of the protection.

[0193] In one embodiment of this application, the structure of the protected Petri net is represented as follows:

[0194] (1)

[0195] In the formula, Describes a finite set of places. A finite set representing change. F This represents the set of directed arcs between places and transitions; Indicates a suppression arc, X This represents the transition trigger vector. W The relation matrix representing places and changes. M This is the state vector of the place in the Petri net.

[0196] The present invention also provides an embodiment of a modeling device for the protection operation risk of a smart substation based on a distributed Petri net, comprising:

[0197] The first construction module is used to construct the Petri net of each protection according to the working principle of the protection corresponding to each primary equipment in the smart substation, using Petri net technology, and construct the corresponding transition and storage association matrix according to the structure of the Petri net of each protection.

[0198] The module adds relevant pressure plates as input spaces to the relevant transition spaces of the Petri net of each protection device using the pressure plate configuration of each protection device in the SCD file; the relevant pressure plates include functional pressure plates, SV receiving pressure plates and maintenance pressure plates;

[0199] The second construction module is used to construct a coupling relationship library for information transmission between protections based on the virtual loop connection information of each protection device in the SCD file. It is used to describe the coupling relationship between the output library of a protection’s Petri net and the input library of the Petri net of related protections, and to construct a coupling state library to store the state information transmitted by each primary device’s dual protection based on the coupling relationship structure to related protections.

[0200] The blocking module is used to set the activation / deactivation status of each pressure plate in the Petri net of the corresponding protection when a primary device fails. This involves setting the input state of the Petri net for that protection, calling the Petri net, and performing deduction and analysis of each stage of the Petri net based on the correlation matrix. According to the coupling relationship library, the module updates the coupling state library using the state values ​​of the output state of the Petri net for that protection, so that these values ​​can be assigned to the relevant input state values ​​of the Petri net for subsequent protections, thus starting the Petri net for subsequent protections. If the protection action corresponding to the primary device failure is not completed, the Petri net for that protection will be blocked.

[0201] In one embodiment of this application, the step of constructing a Petri net for each protection device based on the working principle of the protection corresponding to each primary device in the smart substation, using Petri net technology, and constructing a corresponding transition-storage correlation matrix based on the structure of the Petri net for each protection device, includes:

[0202] The Petri network creation module is used to construct corresponding Petri networks for a smart substation, specifically for the normal operation and blocking status of line protection on the high-voltage side, medium-voltage side, and low-voltage side; for the busbar, it creates Petri networks for busbar protection; it creates Petri networks for the protection of each circuit breaker; and it creates Petri networks for the normal operation of the main transformer protection and Petri networks for the failure tripping of the main transformer protection.

[0203] The correlation matrix construction module is used to construct the corresponding correlation matrix between transitions and places based on the structure of all protected Petri nets obtained from the Petri net construction module. W Correlation matrix W Used to represent the connection relationship between each change and each repository.

[0204] In one embodiment of this application, the association matrix construction module is used for:

[0205] In the association matrix, the element corresponding to an input library and its pointed-to transition is -1; the element corresponding to a transition and its output library is 1; if a library is not associated with any other transition, the element corresponding to that library and that other transition in the association matrix is ​​0; the association matrix... W The elements in the middle are defined as follows:

[0206] (2)

[0207] In the formula, Represented as from change t to the warehouse p The directed arc, Indicated as a warehouse p To change t A directed arc;

[0208] When a place is the input place for multiple transitions, the state of that place can only trigger one transition. To address this, all subsequent transitions from that place are weighted, allowing the place to trigger multiple subsequent transitions simultaneously in a single iteration. The weights are represented as follows:

[0209] (5)

[0210] In the formula, Represented as a directed arc The weight of the library; k When the input library is a change, then The value is 1 / k .

[0211] In one embodiment of this application, the adding module is used for:

[0212] In the Petri net corresponding to each primary device, the sampled value (SV) information of the merging unit is uploaded to the protection device. After receiving the SV information, the protection device issues a trip command and a failure signal. The trip command is transmitted to the intelligent terminal, and the failure signal is transmitted to the adjacent protection device. In the protection Petri net, the corresponding SV receiving pressure plate is used as a condition for uploading the merging unit information, i.e., an input location, to complete the triggering of the first round of transitions. The function pressure plate and the maintenance pressure plate are used as conditions for the protection device to operate, and together with the uploading of the merging unit information, they trigger the second round of transitions. The triggering of the third round of transitions requires that the trip command, the failure signal, and the corresponding GOOSE sending soft pressure plate be in the activated state.

[0213] In one embodiment of this application, the adding module is specifically used for:

[0214] For the Petri network protecting 500kV lines, in its "SV Reception" transition, two circuit breaker 5021 SV receiving pressure plates, 5022 SV receiving pressure plates, and a line SV receiving pressure plate are added as input locations. In the "Protection Function Trigger" transition, protection function pressure plates and maintenance pressure plates are added as input locations. Among them, the maintenance pressure plate location has an arc suppression function, meaning it can only participate in the triggering of this transition when its state value is 0. In the "Send 5021 Trip Command to Smart Terminal" and "Send 5022 Trip Command to Smart Terminal" transitions... In the transition of the "terminal", 5021 trip output pressure plate and 5022 trip output pressure plate are added respectively as their input locations; in the transition of "send 5021 failure signal output" and "send 5022 failure signal output", 5021 failure start pressure plate and 5022 failure start pressure plate are added respectively as their input locations; in this way, corresponding pressure plates are set in each link of the protection, including SV reception, protection action, trip signal transmission, and failure GOOSE signal start, so as to express the different roles of each pressure plate in the 500kV line protection action;

[0215] The addition of pressure plates in Petri networks for busbar protection, transformer protection, and circuit breaker protection is similar to the addition of pressure plates in Petri networks for 500kV line protection.

[0216] In one embodiment of this application, the second construction module is used for:

[0217] Parse the virtual loop connection information of each protection device from the SCD file, that is, the trip GOOSE message sent by a protection device to the smart terminal and the start failure GOOSE message sent to other related protections. Construct a coupling relationship structure to describe the coupling relationship between the output place of a protection Petri net and the input place of related protection Petri nets.

[0218] Based on the virtual loop connection information of each protection output, construct the corresponding coupling relationship structure, and then add them to the coupling relationship structure array to form a coupling relationship library;

[0219] A coupled state library is constructed to store the state information transmitted by the dual protection of each primary device based on the coupling relationship structure. The dual protection is set A protection and set B protection. For each coupling relationship structure, there is a corresponding row in the coupled state library. The first and second columns of the row store the state values ​​of the output library corresponding to set A protection and set B protection in the coupling relationship structure, respectively.

[0220] In one embodiment of this application, the blocking generation module is used to:

[0221] When a primary device malfunctions, the activation / deactivation status of each pressure plate in the Petri net corresponding to that primary device is set, the initial state of the Petri net of the corresponding protection is updated, and the operation of each stage of the Petri net of the protection is simulated; after the Petri net of the protection has finished operating, the transition cumulative trigger vector of the Petri net corresponding to the protection is obtained; and the protection action corresponding to the primary device is analyzed to see if it has been completed.

[0222] If the protection action is not completed, the transition accumulation trigger vector is used to find the untriggered transitions in the Petri net of the protection. Each input place of the transition is checked in turn. If the state value of an input place without a suppression arc is 0, it is determined that the transition was not triggered due to this input place, which causes the protection action corresponding to the Petri net to fail to complete, i.e., the Petri net is blocked. Then, using the coupling relation library, the Petri net of the subsequent protection related to the current Petri net is found. The state value of the output place of the current Petri net is assigned to the state value of the relevant input place of the Petri net of the subsequent protection, and the initial state of the Petri net of the subsequent protection is updated so that the Petri net of the subsequent protection can be started.

[0223] In one embodiment of this application, the blocking generation module includes a deduction and analysis unit; the deduction and analysis unit is used to invoke the Petri net of the protection and, based on the correlation matrix, perform deduction and analysis on each stage of the Petri net of the protection.

[0224] In one embodiment of this application, the deduction and analysis unit includes:

[0225] The configuration subunit is used to set the on / off status of each pressure plate in the Petri net corresponding to the primary equipment when a fault occurs, and to set the storage status vector of the Petri net corresponding to the primary equipment. M Configure settings;

[0226] The calculation sub-unit is used to calculate the place state vectors for each transition. M The system determines whether each transition meets the triggering conditions, performs behavior extrapolation for the current Petri net under protection, and calculates the transition trigger vector for this round. X ;

[0227] Inference subunit, used for transition trigger vector X If there is a non-zero value, indicating that a new transition has been triggered, then the correlation matrix is ​​used. W The storage status vector for this round Transition trigger vector X The state vector of the storage area after this round of simulation is calculated. Repeatedly execute the computation sub-unit; when the transition triggers the vectorX If all values ​​in the middle are 0, meaning no new transitions are triggered, then the state vector of the place after this round of deduction is... The final state value of the repository is given, marking the end of this Petri net simulation. It is a positive integer;

[0228] The inspection sub-unit is used to check the transition trigger vectors of each round after the current Petri net run simulation is completed. X The elements in each column are summed to obtain the cumulative transition trigger vector of the Petri net. According to vectors Check whether the various transitions of the trip command and failure signal that the protection needs to issue have been triggered. If all transitions have been triggered, the protection action is completed; otherwise, the protection action is not completed.

[0229] The assignment sub-unit is used to find the Petri nets of subsequent protections related to the Petri net of the current protection using the coupling relationship library, store the state value of the output library of the current Petri net into the coupling state library, and assign it to the state value of the input library of the subsequent Petri net so that the Petri nets of subsequent protections can receive the state value sent by the superior and be started and perform deduction.

[0230] The iterative subunit is used to repeatedly call the calculation subunit, deduction subunit, check subunit, and assignment subunit for other protections in the smart substation. This allows for the deduction and analysis of the Petri net for each protection, and the transmission of instructions to the Petri net of the relevant protection.

[0231] In one embodiment of this application, the setting subunit is used for:

[0232] If a pressure plate is engaged, the status value of the corresponding pressure plate storage area is set to 1; the Petri net of the protection corresponding to the primary fault device is used as the Petri net of the current protection; based on the storage area status vector required by the Petri net of the protection corresponding to the primary device and the engagement / disengagement status of a single pressure plate, the storage area status vector of the Petri net is set. M Initial state vector M 0.

[0233] In one embodiment of this application, the computing subunit is used for:

[0234] If the first one does not contain the suppressor arc The first change, then the second Triggering state of each transition The calculation is as follows:

[0235] (3)

[0236] In the formula, n Indicates the first The number of input locations for each transition; It is the first n The status values ​​of each input library; It is a transition trigger vector X The first in One element;

[0237] The first arc can only be triggered when the state values ​​of all input libraries without suppression arcs are greater than 0. A transition, a transition trigger vector X The corresponding number in The value of the nth element is 1; otherwise, it is 0, i.e., the nth element is 0. One cannot be triggered;

[0238] If a transition involves an input place with a suppression arc, the transition can only be triggered if the state values ​​of all input places without suppression arcs are greater than 0, while the state values ​​of input places with suppression arcs are all less than 0. The first change, the Triggering state of each transition The calculation is as follows:

[0239] (4)

[0240] In the formula, For the first n The state value of an input library without a suppression arc. For the first k The state value of an input library containing a suppression arc. It is the number of the input location containing the suppression arc; It is a transition trigger vector X The first in One element;

[0241] When a place is the input place of multiple transitions, assuming the initial state value of the place is 1, after a transition pointed to by the output of the place is triggered, through the derivation of the transition, the state value of the place becomes 1-1 / k. Since the state value of the place is still greater than 0, other transitions can continue to be triggered.

[0242] The deduction subunit is used for:

[0243] No. j The formula for calculating the state vector of a storage location in a given round is:

[0244] (6)

[0245] In the formula, For the first State vectors of each warehouse before the round of simulation; For the first The state vectors of each depot after round of simulation; Transition trigger vector; This is the correlation matrix between locations and changes.

[0246] In one embodiment of this application, a risk point identification unit is provided between the inspection subunit and the assignment subunit, the risk point identification unit being used for:

[0247] If the protection action is completed, then proceed to the assignment sub-unit and utilize the final... Update the coupling state library; if the protection action is not completed, find the abnormal transition and the reason why the abnormal transition was not triggered; accumulate the trigger vector based on the transition. If the value of an element is 0, find the untriggered transition in the Petri net; first, judge the transition. If the parent transition of the untriggered transition is also not triggered, then there is no need to check the input library of the current transition; if a parallel transition of the current transition has been triggered, then there is no need to check the input library of the current transition.

[0248] For transitions that are not triggered after screening, check the status values ​​of each input location of the transition in sequence. If the status value of an input location without a suppression arc is 0, it means that the input location is abnormal. If the status value of an input location with a suppression arc is 1, it is determined that the input location is abnormal. The abnormal location is the reason why the protection of the primary device is blocked in this transition, thereby discovering the possible risk location of the protection, which helps to find the risk point of the protection.

[0249] In one embodiment of this application, the structure of the protected Petri net is represented as follows:

[0250] (1)

[0251] In the formula, Describes a finite set of places. A finite set representing change. F This represents the set of directed arcs between places and transitions; Indicates a suppression arc, X This represents the transition trigger vector. W The relation matrix representing places and changes. M This is the state vector of the place in the Petri net.

[0252] For ease of understanding, the present invention provides a more specific embodiment:

[0253] Example 1:

[0254] Example 1 corresponds to the 500kV substation main wiring diagram as follows: Figure 2 As shown;

[0255] Specific experiments are designed to demonstrate the effectiveness of the proposed modeling method for the operational risk of smart substation protection based on distributed Petri nets. The details are as follows:

[0256] Distributed Petri nets for 500kV line protection, such as Figure 3 As shown.

[0257] (1) Based on the relationship between the Petri network database and the changes during normal operation of 500kV line protection, construct the correlation matrix W as follows:

[0258]

[0259] (2) Obtain the initial state of the corresponding warehouse.

[0260] Assuming a fault occurs in this line, and all pressure plates are correctly engaged and disengaged, then the Petri net of this line... as follows:

[0261]

[0262] (3) Based on the input state of each transition, formulate rules to determine whether each transition is triggered, as follows:

[0263]

[0264]

[0265]

[0266]

[0267]

[0268]

[0269]

[0270]

[0271] Therefore, based on the initial state of the warehouse... Obtain the transition trigger vector of the first round of the Petri net. :

[0272]

[0273] (4) Calculate the warehouse status after the first round according to the warehouse status calculation formula (6). :

[0274]

[0275] (5) After repeating the calculations in steps (3) and (4), the transition trigger vectors for the second and third rounds are obtained in sequence. , :

[0276]

[0277]

[0278] The results of the fourth round of reasoning are as follows:

[0279]

[0280]

[0281] (6) Use The transition trigger vector for round 5 is calculated. When it is a vector of all zeros, the Petri net can be obtained after running for 4 rounds. This represents the final state of each storage location; the cumulative transition trigger vector at this point is:

[0282]

[0283] Therefore, this Petri net simulation went through four rounds with no untriggered transitions. (Ku place state) middle This indicates that both circuit breakers in the circuit have tripped; This indicates that all protection failure signals have been transmitted to the relevant protection system, and the protection function has been completed.

[0284] (7) Based on the coupling relationship library The two structures that transmit trip and failure signals from the line protection to the adjacent circuit breaker protection are as follows:

[0285] P1=struct('AC','PL5021','ACNUM',28,'TR','PB5021','TRNUM',1,'ACtype','L','TRtype','S');

[0286] P1 indicates that the final state value of the storage unit numbered 28 in the Petri net (protection model type L) of the normal operation of the PL5021 line protection is transferred to the state of the storage unit numbered 1 in the Petri net (protection model type S) of the normal operation of the PB5021 circuit breaker protection.

[0287] P2=struct('AC','PL5021','ACNUM',29,'TR','PB5022','TRNUM',1,'ACtype','L','TRtype','S');

[0288] P2 indicates that the final state value of the storage unit numbered 29 in the Petri net (protection model type L) for normal operation of the PL5021 line protection is transferred to the state of the storage unit numbered 1 in the Petri net (protection model type S) for normal operation of the 5022 circuit breaker protection.

[0289] P5=struct('AC','PL5021','ACNUM',30,'TR','PB5021','TRNUM',5,'ACtype','L','TRtype','S');

[0290] P5 indicates that the final state value of the storage unit numbered 30 in the Petri net (protection model type L) for normal operation of the PL5021 line protection is transferred to the state of the storage unit numbered 5 in the Petri net (protection model type S) for normal operation of the PB5021 circuit breaker protection.

[0291] P6=struct('AC','PL5021','ACNUM',31,'TR','PB5022','TRNUM',5,'ACtype','L','TRtype','S');

[0292] P6 indicates that the final state value of the storage unit numbered 31 in the Petri net (protection model type L) for normal operation of the PL5021 line protection is transferred to the state of the storage unit numbered 5 in the Petri net (protection model type S) for normal operation of the PB5022 circuit breaker protection.

[0293] Based on the above coupling relationship library Update the coupled state library based on the state values ​​of the relevant output library in the Petri net execution results. ,as follows:

[0294]

[0295] exist middle, A value of 1 indicates that after the protection of line A is activated, the failure signal and trip information will be transmitted to the corresponding storage areas of the two adjacent circuit breaker A protection units via the GOOSE link.

[0296] Example 2:

[0297] Based on Example 1, if the 5021GOOSE outlet soft pressure plate in the line protection fails to activate, and the status of the other depots is normal, the initial state values ​​of each depot in the Petri network are as follows:

[0298]

[0299] Following the Petri net derivation steps in Example 1, the transition trigger vectors for each round can be obtained. and warehouse status for:

[0300] Round 1:

[0301]

[0302]

[0303] Round 2:

[0304]

[0305]

[0306] Round 3:

[0307]

[0308]

[0309] Round 4:

[0310]

[0311]

[0312] The Petri net simulation was completed in its fourth run, at which point the cumulative transition trigger vector was:

[0313]

[0314] because ,and for When transition 7's parent transition 3 is also not triggered, there is no need to determine the cause of transition 7's anomaly; therefore, it is only necessary to determine the cause of transition 3's failure to trigger. Checking the status of each input location of transition 3, it is found that the status value of input location number 15 is 0, i.e. (5021GOOSE output pressure plate not engaged) means that transition 3 was not triggered because the 5021GOOSE output pressure plate was not engaged, which in turn caused the protection operation to be incomplete.

[0315] Final round middle If the circuit breaker 5021 does not trip, then the circuit breaker 5022 will trip. If all protection failure signals are transmitted, then the line protection is not operating completely. The abnormal transition is transition 3, which was not triggered because the 5021GOOSE output pressure plate was not engaged, which is the cause of the Petri net blockage.

[0316] Update the coupling state library ,as follows:

[0317]

[0318] In the formula, A value of 1 indicates that after the protection of line A is activated, the failure signal and trip information will be transmitted to the protection of line 5022 circuit breaker A via the GOOSE link, and the failure signal will be transmitted to the protection of line 5021 circuit breaker A.

[0319] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the protection scope of the claims of the present invention.

Claims

1. A modeling method for the protection operation risk of smart substations based on distributed Petri nets, characterized in that, include: Based on the working principle of the protection corresponding to each primary device in the smart substation, Petri net technology is used to construct the Petri net for each protection. Based on the structure of the Petri net for each protection, the corresponding transition and storage correlation matrix is ​​constructed. Using the pressure plate configuration of each protection device in the SCD file, the relevant pressure plates are added as input places to the relevant transitions of the Petri net of each constructed protection. The relevant pressure plates include functional pressure plates, SV receiving pressure plates, and maintenance pressure plates. Parse the virtual loop connection information of each protection device from the SCD file, that is, the trip GOOSE message sent by a protection device to the smart terminal and the start failure GOOSE message sent to other related protections. Construct a coupling relationship structure to describe the coupling relationship between the output place of a protection Petri net and the input place of related protection Petri nets. Based on the virtual loop connection information of each protection output, construct the corresponding coupling relationship structure, and then add them to the coupling relationship structure array to form a coupling relationship library; A coupled state library is constructed to store the state information transmitted by the dual protection of each primary device based on the coupling relationship structure. The dual protection is set A and set B. For each coupling relationship structure, there is a corresponding row in the coupled state library. The first and second columns of the row store the state values ​​of the output library corresponding to set A protection and set B protection in the coupling relationship structure, respectively. When a primary device fails, the activation / deactivation status of each pressure plate in the Petri net corresponding to that primary device is set, the initial state of the Petri net of the corresponding protection is updated, and the operation of the Petri net of the protection at each stage is simulated. After the Petri net of the protection has finished running, obtain the transition cumulative trigger vector of the Petri net corresponding to the protection; analyze whether the protection action corresponding to the primary device has been completed; If the protection action is not completed, the transition that has not been triggered in the Petri net of the protection is found by the transition accumulation trigger vector. Each input place of the transition is checked in turn. If the state value of an input place without a suppression arc is 0, it is determined that the transition was not triggered because of the input place. The protection action corresponding to the Petri net has not been completed and the Petri net is blocked. Then, using the coupling relationship library, find the Petri nets for subsequent protection related to the current Petri net, assign the state value of the output library of the current Petri net to the state value of the input library of the Petri net for subsequent protection, update the initial state of the Petri net for subsequent protection, so that the Petri net for subsequent protection can be started.

2. The method according to claim 1, characterized in that, Based on the working principle of the protection corresponding to each primary device in the intelligent substation, Petri net technology is used to construct the Petri net for each protection. Based on the structure of the Petri net for each protection, the corresponding transition and storage location correlation matrix is ​​constructed, including: Step 11: For a smart substation, construct corresponding Petri networks for line protection on the high-voltage side, medium-voltage side, and low-voltage side; establish Petri networks for bus protection; establish Petri networks for circuit breaker protection; and establish Petri networks for main transformer protection. Step 12: Based on the structure of all the protected Petri nets obtained in Step 11, construct the corresponding transition-place correlation matrix. W Correlation matrix W Used to represent the connection relationship between each change and each repository.

3. The method according to claim 2, characterized in that, Step 12 includes: An input library and its corresponding transition in the association matrix have an element of -1; a transition and its corresponding output library have an element of 1; if a library is not associated with any other transition, the element corresponding to that library and that other transition in the association matrix is ​​0; the association matrix... W The elements in the middle are defined as follows: （2） In the formula, Represented as from change t to the warehouse p The directed arc, Indicated as a warehouse p To change t A directed arc; When a place is the input place for multiple transitions, the state of that place can only trigger one transition. To address this, all subsequent transitions from that place are weighted, allowing the place to trigger multiple subsequent transitions simultaneously in a single iteration. The weights are represented as follows: （5） In the formula, Represented as a directed arc The weight of the library; k When the input library is a change, then The value is 1 / k .

4. The method according to claim 1, characterized in that, The step of using the pressure plate configuration of each protection device in the SCD file to add the relevant pressure plates as input places to the relevant transitions of the constructed Petri net of each protection includes: In the Petri net corresponding to each primary device, the sampled value (SV) information of the merging unit is uploaded to the protection device. After receiving the SV information, the protection device issues a trip command and a failure signal. The trip command is transmitted to the intelligent terminal, and the failure signal is transmitted to the adjacent protection device. In the protection Petri net, the corresponding SV receiving pressure plate is used as a condition for uploading the merging unit information, i.e., an input location, to complete the triggering of the first round of transitions. The function pressure plate and the maintenance pressure plate are used as conditions for the protection device to operate, and together with the uploading of the merging unit information, they trigger the second round of transitions. The triggering of the third round of transitions requires that the trip command, the failure signal, and the corresponding GOOSE sending soft pressure plate be in the activated state.

5. The method according to claim 1, characterized in that, The step of using the pressure plate configuration of each protection device in the SCD file to add the relevant pressure plates as input places to the relevant transitions of the constructed Petri net of each protection specifically includes: For the Petri network protecting 500kV lines, in its "SV Reception" transition, two circuit breaker 5021 SV receiving pressure plates, 5022 SV receiving pressure plates, and a line SV receiving pressure plate are added as input locations; in the "Protection Function Trigger" transition, protection function pressure plates and maintenance pressure plates are added as input locations. The maintenance pressure plate location has an arc suppression feature, meaning it can only participate in triggering this transition when its state value is 0; in the "Send 5021 Trip Command to Smart Terminal" and "Send 5022 Trip Command to Smart Terminal" transitions... In the transition of the "power terminal", 5021 trip output pressure plate and 5022 trip output pressure plate are added respectively as their input locations; in the transition of "send 5021 failure signal output" and "send 5022 failure signal output", 5021 failure start pressure plate and 5022 failure start pressure plate are added respectively as their input locations; in each stage of the protection's SV reception, protection action, trip signal transmission, and failure GOOSE signal start, corresponding pressure plates are set to express the different roles of each pressure plate in the 500kV line protection action.

6. The method according to claim 1, characterized in that, The Petri net of this protection is invoked, and based on the correlation matrix, each stage of the Petri net is derived and analyzed, including: Step 401: Set the on / off status of each pressure plate in the Petri net corresponding to the primary equipment in case of a fault, and set the storage status vector of the Petri net corresponding to the primary equipment. M Configure settings. Step 402: Based on the place state vectors of each transition M The system determines whether each transition meets the triggering conditions, performs behavior extrapolation for the current Petri net under protection, and calculates the transition trigger vector for this round. X ; Step 403: If the transition trigger vector X If there is a non-zero value, indicating that a new transition has been triggered, then the correlation matrix is ​​used. W The storage status vector for this round Transition trigger vector X The state vector of the storage area after this round of simulation is calculated. Repeat step 402; when the transition triggers the vector X If all values ​​in the middle are 0, meaning no new transitions are triggered, then the state vector of the place after this round of deduction is... The final state value of the repository is given, marking the end of this Petri net simulation. It is a positive integer; Step 404: After the Petri net simulation for the current protection is completed, the transition trigger vectors for each round are... X The elements in each column are summed to obtain the cumulative transition trigger vector of the Petri net. According to vectors Check whether the various transitions of the trip command and failure signal that the protection needs to issue have been triggered. If all transitions have been triggered, the protection action is completed; otherwise, the protection action is not completed. Step 405: Using the coupling relationship library, find the Petri nets of each subsequent protection related to the current Petri net, store the state value of the output library of the current Petri net into the coupling state library, and assign it to the state value of the input library of the subsequent Petri net, so that the Petri nets of each subsequent protection can receive the state value sent by the superior and be started and perform deduction. Step 406: For other protections in the smart substation, repeat steps 402 to 405 to perform the deduction and analysis of the Petri net for each protection, and transmit instructions to the Petri net of the relevant protection.

7. The method according to claim 6, characterized in that, Step 401 includes: If a pressure plate is engaged, the status value of the corresponding pressure plate storage area is set to 1; the Petri net corresponding to the primary fault device is used as the current protection Petri net; based on the storage area status required for normal operation of the protection corresponding to the primary device, and the engagement / disengagement status of individual pressure plates, the initial status of each storage area in the Petri net is set. M 0.

8. The method according to claim 6, characterized in that, Step 402 includes: If the first If the input library of the nth transition does not contain a suppression arc, then the nth transition... Triggering state of each transition The calculation is as follows: （3） In the formula, n Indicates the first The number of input locations for each transition; It is the first n The status values ​​of each input library; It is a transition trigger vector X The first in One element; The first arc can only be triggered when the state values ​​of all input libraries without suppression arcs are greater than 0. The transition, the corresponding transition trigger vector in the transition _ ... The value of the nth element is 1; otherwise, it is 0, i.e., the nth element is 0. One cannot be triggered; If the first If the input library of a transition contains a suppression arc, then the state value of all input libraries without suppression arcs is greater than 0, while the state value of all input libraries containing suppression arcs is less than 0, to trigger the transition. The first change, the Triggering state of each transition The calculation is as follows: （4） In the formula, For the first n The state value of an input library without a suppression arc. For the first k The state value of an input library containing a suppression arc. It is the number of the input location containing the suppression arc; It is a transition trigger vector X The first in One element; When a place is the input place of multiple transitions, assuming the initial state value of the place is 1, after a transition pointed to by the output of the place is triggered, through the derivation of that transition, the state value of the place becomes 1-1 / k If the state value of this place is still greater than 0, then other transitions will continue to be triggered; Step 403 includes: No. j The formula for calculating the status of warehouses in each round is: （6） In the formula, For the first State vectors of each warehouse before the round of simulation; For the first The state vectors of each storage location after round of simulation; Transition trigger vector; This is the correlation matrix between locations and changes.

9. The method according to claim 6, characterized in that, After step 404 and before step 405, the method further includes: If the protection action is completed, proceed to step 405, using the final storage state vector. Update the coupling state library; if the protection action is not completed, find the abnormal transition and the reason why the abnormal transition was not triggered; if the transition cumulative trigger vector If the value of an element is 0, then find all untriggered transitions in the Petri net; first, judge the transition. If the parent transition of the untriggered transition is also untriggered, then there is no need to check the input library of the current transition; if a parallel transition of the current transition has been triggered, then there is no need to check the input library of the current transition. For transitions that are not triggered after screening, check the status values ​​of each input location of the transition in sequence. If the status value of an input location without a suppression arc is 0, it means that the input location is abnormal. If the status value of an input location with a suppression arc is 1, it is determined that the input location is abnormal. The abnormal location is the reason why the protection of the primary device is blocked in this transition.

10. The method according to any one of claims 1-9, characterized in that, The structure of the protected Petri net is represented as follows: （1） In the formula, Describes a finite set of places. A finite set representing change. This represents the set of directed arcs between places and transitions; Indicates a suppression arc, This represents the transition trigger vector. The relation matrix representing places and changes. This is the state vector of the place in the Petri net.

11. A modeling device for the operational risk of intelligent substation protection based on distributed Petri nets, characterized in that, include: The first construction module is used to construct the Petri net of each protection according to the working principle of the protection corresponding to each primary equipment in the smart substation, using Petri net technology, and construct the corresponding transition and storage association matrix according to the structure of the Petri net of each protection. The module adds relevant pressure plates as input spaces to the relevant transition spaces of the Petri net of each protection device using the pressure plate configuration of each protection device in the SCD file; the relevant pressure plates include functional pressure plates, SV receiving pressure plates and maintenance pressure plates; The second construction module is used to: parse the virtual loop connection information of each protection device from the SCD file, that is, the trip GOOSE message sent by a protection device to the intelligent terminal and the start failure GOOSE message sent to other related protections; construct a coupling relationship structure to describe the coupling relationship between the output library of a protection's Petri net and the input library of related protection's Petri net; construct the corresponding coupling relationship structure according to the virtual loop connection information of each protection output, and then add them to the coupling relationship structure array to form a coupling relationship library; A coupled state library is constructed to store the state information transmitted by the dual protection of each primary device based on the coupling relationship structure. The dual protection is set A and set B. For each coupling relationship structure, there is a corresponding row in the coupled state library. The first and second columns of the row store the state values ​​of the output library corresponding to set A and set B protection in the coupling relationship structure, respectively. The blocking module is used to: set the activation / deactivation status of each pressure plate in the Petri net corresponding to the primary equipment when a fault occurs, update the initial state of the Petri net of the corresponding protection, and perform simulation of the operation of the Petri net of the protection at each stage. After the Petri net of the protection is completed, the transition cumulative trigger vector of the Petri net corresponding to the protection is obtained; it is analyzed whether the protection action corresponding to the primary device is completed; if the protection action is not completed, the transition that has not been triggered in the Petri net of the protection is found by the transition cumulative trigger vector, and each input place of the transition is checked in turn. If the state value of an input place without a suppression arc is 0, it is determined that the transition was not triggered due to the input place, the protection behavior corresponding to the Petri net failed to be completed, and the Petri net is blocked. Then, using the coupling relationship library, find the Petri nets for subsequent protection related to the current Petri net, assign the state value of the output library of the current Petri net to the state value of the input library of the Petri net for subsequent protection, update the initial state of the Petri net for subsequent protection, so that the Petri net for subsequent protection can be started.

12. The apparatus according to claim 11, characterized in that, The first construction module includes: The Petri network creation module is used to construct corresponding Petri networks for line protection on the high-voltage side, medium-voltage side, and low-voltage side of a smart substation; to establish Petri networks for bus protection; to establish Petri networks for circuit breaker protection; and to establish Petri networks for main transformer protection. The correlation matrix construction module is used to construct the corresponding correlation matrix between transitions and places based on the structure of all protected Petri nets obtained from the Petri net construction module. W Correlation matrix W Used to represent the connection relationship between each change and each repository.

13. The apparatus according to claim 12, characterized in that, The correlation matrix construction module is used for: Let the element corresponding to an input library and its pointed-to transition in the association matrix be -1; the element corresponding to a transition and its pointed-to output library in the association matrix be 1; if a library is not associated with any other transition, then the element corresponding to that library and that other transition in the association matrix is ​​0; the association matrix... W The elements in the middle are defined as follows: （2） In the formula, Represented as from change t to the warehouse p The directed arc, Indicated as a warehouse p To change t A directed arc; When a place is the input place for multiple transitions, the state of that place can only trigger one transition. To address this, all subsequent transitions from that place are weighted, allowing the place to trigger multiple subsequent transitions simultaneously in a single iteration. The weights are represented as follows: （5） In the formula, Represented as a directed arc The weight of the library; k When the input library is a change, then The value is 1 / k .

14. The apparatus according to claim 11, characterized in that, The added module is used for: In the Petri net corresponding to the protection of each primary device, the sampled value (SV) information of the merging unit is uploaded to the protection device; after receiving the SV information, the protection device issues a trip command and a failure start signal; When a trip command is transmitted to the smart terminal and a failure signal is transmitted to the adjacent protection device, the corresponding SV receiving pressure plate in the protection Petri net is used as a condition for uploading the merged unit information, i.e., an input location, to complete the triggering of the first round of transitions. The function pressure plate and maintenance pressure plate are used as conditions for the protection device to operate, and together with the uploading of the merged unit information, they trigger the second round of transitions. The triggering of the third round of transitions requires that the trip command, failure information, and their corresponding GOOSE sending soft pressure plate be in the enabled state.

15. The apparatus according to claim 11, characterized in that, The added module is specifically used for: For the Petri network protecting 500kV lines, in its "SV Reception" transition, two circuit breaker 5021 SV receiving pressure plates, 5022 SV receiving pressure plates, and a line SV receiving pressure plate are added as input locations; in the "Protection Function Trigger" transition, protection function pressure plates and maintenance pressure plates are added as input locations. The maintenance pressure plate location has an arc suppression feature, meaning it can only participate in triggering this transition when its state value is 0; in the "Send 5021 Trip Command to Smart Terminal" and "Send 5022 Trip Command to Smart Terminal" transitions... In the transition of the "power terminal", 5021 trip output pressure plate and 5022 trip output pressure plate are added respectively as their input locations; in the transition of "send 5021 failure signal output" and "send 5022 failure signal output", 5021 failure start pressure plate and 5022 failure start pressure plate are added respectively as their input locations; in each stage of the protection's SV reception, protection action, trip signal transmission, and failure GOOSE signal start, corresponding pressure plates are set to express the different roles of each pressure plate in the 500kV line protection action.

16. The apparatus according to claim 11, characterized in that, The blocking module includes a deduction and analysis unit; the deduction and analysis unit is used to call the Petri net of the protection and, based on the correlation matrix, perform deduction and analysis on each stage of the Petri net of the protection.

17. The apparatus according to claim 16, characterized in that, The deduction and analysis unit includes: The configuration subunit is used to set the on / off status of each pressure plate in the Petri net corresponding to the primary equipment when a fault occurs, and to set the storage status vector of the Petri net corresponding to the primary equipment. M Configure settings; The calculation sub-unit is used to calculate the place state vectors for each transition. M The system determines whether each transition meets the triggering conditions, performs behavior extrapolation for the current Petri net under protection, and calculates the transition trigger vector for this round. X ; Inference subunit, used for transition trigger vector X If there is a non-zero value, indicating that a new transition has been triggered, then the correlation matrix is ​​used. W The storage status vector for this round Transition trigger vector X The state vector of the storage area after this round of simulation is calculated. Repeatedly execute the computation sub-unit; when the transition triggers the vector X If all values ​​in the middle are 0, meaning no new transitions are triggered, then the state vector of the place after this round of deduction is... The final state value of the repository is given, marking the end of this Petri net simulation. It is a positive integer; The inspection sub-unit is used to check the transition trigger vectors of each round after the current Petri net run simulation is completed. X The elements in each column are summed to obtain the cumulative transition trigger vector of the Petri net. According to vectors Check whether the various transitions of the trip command and failure signal that the protection needs to issue have been triggered. If all transitions have been triggered, the protection action is completed; otherwise, the protection action is not completed. The assignment sub-unit is used to find the Petri nets of subsequent protections related to the Petri net of the current protection using the coupling relationship library, store the state value of the output library of the current Petri net into the coupling state library, and assign it to the state value of the input library of the subsequent Petri net so that the Petri nets of subsequent protections can receive the state value sent by the superior and be started and perform deduction. The iterative subunit is used to repeatedly call the calculation subunit, deduction subunit, check subunit, and assignment subunit in sequence for other protections in the smart substation, so as to realize the deduction and analysis of the Petri net of each protection and pass the instructions to the Petri net of the relevant protection.

18. The apparatus according to claim 17, characterized in that, The setting subunit is used for: If a pressure plate is engaged, the status value of the corresponding pressure plate storage area is set to 1; the Petri net of the protection corresponding to the primary fault device is used as the Petri net of the current protection; based on the storage area status vector required by the Petri net of the protection corresponding to the primary device and the engagement / disengagement status of a single pressure plate, the storage area status vector of the Petri net is set. M Initial state vector M 0.

19. The apparatus according to claim 17, characterized in that, The computational subunit is used for: If the first If the input library of the nth transition does not contain a suppression arc, then the nth transition... Triggering state of each transition The calculation is as follows: （3） In the formula, n Indicates the first The number of input locations for each transition; It is the first n The status values ​​of each input library; It is a transition trigger vector X The first in One element; The first arc can only be triggered when the state values ​​of all input libraries without suppression arcs are greater than 0. A transition, a transition trigger vector X The corresponding number in The value of the nth element is 1; otherwise, it is 0, i.e., the nth element is 0. One cannot be triggered; If the first If the input library of a transition contains a suppression arc, then the state value of all input libraries without suppression arcs is greater than 0, while the state value of all input libraries containing suppression arcs is less than 0, to trigger the transition. The first change, the Triggering state of each transition The calculation is as follows: （4） In the formula, For the first n The state value of an input library without a suppression arc. For the first k The state value of an input library containing a suppression arc. It is the number of the input location containing the suppression arc; It is a transition trigger vector X The first in One element; When a place is the input place of multiple transitions, assuming the initial state value of the place is 1, after a transition pointed to by the output of the place is triggered, the state value of the place becomes 1-1 / k after the derivation of the transition. If the state value of the place is still greater than 0, other transitions are triggered. The deduction subunit is used for: Order No. j The formula for calculating the state vector of a storage location in a given round is: （6） In the formula, For the first State vectors of each warehouse before the round of simulation; For the first The state vectors of each storage location after round of simulation; Transition trigger vector; This is the correlation matrix between locations and changes.

20. The apparatus according to claim 17, characterized in that, A risk point identification unit is provided between the inspection subunit and the assignment subunit, and the risk point identification unit is used for: If the protection action is completed, the process moves to the assignment sub-unit, utilizing the final storage state vector. Update the coupling state library; if the protection action is not completed, find the abnormal transition and the reason why the abnormal transition was not triggered; if the transition cumulative trigger vector If the value of an element is 0, then an untriggered transition in the Petri net is found. First, the transition is judged. If the parent transition of the untriggered transition is also untriggered, then there is no need to check the input library of the current transition. If a parallel transition of the current transition has been triggered, then there is no need to check the input library of the current transition. For transitions that are not triggered after screening, check the status values ​​of each input location of the transition in sequence. If the status value of an input location without a suppression arc is 0, it means that the input location is abnormal. If the status value of an input location with a suppression arc is 1, it is determined that the input location is abnormal. The abnormal location is the reason why the protection of the primary device is blocked in this transition.

21. The apparatus according to any one of claims 11-20, characterized in that, The structure of the protected Petri net is represented as follows: （1） In the formula, Describes a finite set of places. A finite set representing change. F This represents the set of directed arcs between places and transitions; Indicates a suppression arc, X This represents the transition trigger vector. W The relation matrix representing places and changes. M This is the state vector of the place in the Petri net.

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