Method and system for online splicing of medium and low voltage network data based on power flow adjustment

Abstract

The application discloses a method and system for online splicing of medium and low voltage network data based on power flow adjustment. Through offline station identification and network topology analysis, each medium and low voltage network and its boundary branch in offline mode data are identified. Based on the correspondence between online equipment and offline equipment, the measured data is used to correct the node injection power of the medium and low voltage network, and the medium and low voltage network data to be spliced is obtained through power flow adjustment. By modifying the topology information of the boundary branch, the medium and low voltage network data after power flow adjustment and online data are spliced together to generate full network data meeting online security and stability analysis, thereby improving the completeness of online security and stability analysis basic data and the accuracy of online security analysis calculation results.

Description

Technical Field

[0001] This invention relates to a method for online splicing of medium and low voltage network data based on power flow adjustment, belonging to the field of power system safety and stability analysis technology. Background Technology

[0002] With the rapid development of ultra-high voltage AC / DC power grid construction, the large-scale development of renewable energy, and the gradual advancement of power market reform, regional power grids in my country are gradually becoming organically interconnected. The scale of the power grid is constantly expanding, the amount of new energy power generation and its proportion are both increasing, the power grid structure and operation mode are becoming increasingly complex, and various global safety and stability risks are constantly increasing. These changes have raised higher technical requirements for the automation and intelligence level of power grid dispatching and management.

[0003] To address the increasing potential risks to the safe and stable operation of the power grid, dispatch centers at all levels across the country and provinces have established online safety analysis applications for smart grid dispatching technology support systems, which have become crucial technical support for the safe and stable operation of the power grid. These online safety analysis applications can perform rolling scans based on real-time power grid operation data, promptly identifying safety and stability issues or potential hazards in the power grid, and providing corresponding auxiliary decision-making suggestions to improve the large-scale power grid management capabilities of dispatching personnel. However, the state estimation data modeling scope used in existing online safety analysis applications typically only covers networks at voltage levels of 220kV and above. A large number of new energy sources, small hydropower plants, and new loads in low-voltage networks at voltage levels of 110kV and below are treated as equivalent, resulting in significant deviations between online analysis results and actual power grid operation. Summary of the Invention

[0004] This invention addresses the technical problem that a large number of new energy sources, small hydropower plants, and new loads in current medium and low voltage networks are treated as equivalent, resulting in a large deviation between online analysis results and actual power grid operation. It provides an online data splicing method for medium and low voltage networks based on power flow adjustment.

[0005] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution.

[0006] In a first aspect, the present invention provides an online splicing method for medium and low voltage network data based on power flow adjustment, including: offline equipment modeling and offline plant identification based on offline typical mode data;

[0007] Based on the correspondence between online and offline power plants, medium and low voltage networks are identified for typical offline methods to obtain each medium and low voltage network and its boundary branches.

[0008] Based on the correspondence between online and offline devices, measured data from SCADA (Supervisory Control And Data Acquisition) / Safety and Stability Control System are used to correct data and adjust power flow in medium and low voltage networks, resulting in power flow-adjusted medium and low voltage network data.

[0009] Set the topology node number and topology island number of the main network side endpoint of the boundary branch of each medium and low voltage network to the topology node number and topology island number of the corresponding online equivalent equipment, and shut down the corresponding online equivalent equipment; combine the medium and low voltage network data after power flow adjustment with the online data to obtain the whole network data.

[0010] Furthermore, the generation process of the medium- and low-voltage network and its boundary branches is as follows:

[0011] Based on the correspondence between offline and online power plants, the associated online equivalent equipment set for each offline power plant is selected from the online data; the online equivalent equipment includes online equivalent loads and online equivalent generators.

[0012] From the set of associated equipment in the offline substation, select AC line segments and transformer windings with the same highest voltage level as the set of associated online equivalent equipment as the set of associated boundary branch equipment for the offline substation;

[0013] The associated boundary branch equipment set and associated online equivalent equipment set of offline power plants are sorted respectively to obtain the associated boundary branch equipment sorting table and associated online equivalent equipment sorting table of offline power plants;

[0014] The associated boundary branch equipment and associated online equivalent equipment of offline power plants are matched one by one to obtain the correspondence between the boundary branch equipment and the online equivalent equipment;

[0015] Based on offline data containing device models and topology relationships, starting from successfully matched boundary branch devices, a depth-first search algorithm is used to expand towards online unmodeled networks and low-voltage networks. Based on the nodes and branches that can be found through topology search, the medium and low-voltage networks are determined, and the boundary branches of the medium and low-voltage networks are identified.

[0016] Furthermore, the process for generating the offline power plant and its associated equipment set is as follows:

[0017] Based on online device modeling and naming rules, offline typical data is converted into offline data containing device models and topological relationships;

[0018] The switch branches, series capacitors, series reactors and transformer windings in the offline data are taken as branches, and the computing nodes are taken as nodes to perform topology analysis, so as to obtain the topology island and the topology nodes contained therein.

[0019] Each topology island is marked as an offline plant, and the set of associated devices of all topology nodes within the topology island is taken as the set of associated devices of the corresponding offline plant.

[0020] Furthermore, the generation process of the boundary branch equipment sorting table and the online equivalent equipment sorting table is as follows:

[0021] For boundary branch equipment, firstly, it is sorted according to the priority order of "three-winding transformers first, two-winding transformers second, and AC line segments last". Then, boundary branch equipment of the same priority is sorted according to the voltage level from high to low. Finally, boundary branch equipment of the same voltage level is sorted according to the rated capacity or rated current from large to small, forming a boundary branch equipment sorting table.

[0022] For online equivalent equipment, the priority order is first set according to the order of "three-winding transformer equivalent equipment first, two-winding transformer equivalent equipment second, and AC line segment equivalent equipment last". Then, online equivalent equipment of the same priority is sorted in the order of voltage level from high to low. Finally, online equivalent equipment of the same voltage level is sorted in the order of rated capacity or rated current from large to small, forming an online equivalent equipment sorting table.

[0023] The matching strategy between the boundary branch equipment and the online equivalent equipment is as follows:

[0024] First, for boundary branch equipment and online equivalent equipment, a matching process is carried out based on the principle that the equipment type, voltage level, rated current or rated capacity are the same.

[0025] Next, for the remaining unmatched boundary branch equipment and online equivalent equipment, a second matching process is performed based on the principle that the equipment type and voltage are the same.

[0026] Then, for the remaining unmatched boundary branch equipment and online equivalent equipment, three matching processes are performed according to the principle of the same equipment type;

[0027] Finally, unmatched boundary branches are removed from the associated boundary branch equipment set of offline substations, and unmatched online equivalent equipment is removed from the associated online equivalent equipment set of offline substations.

[0028] The data correction and power flow adjustment processes for each medium and low voltage network are as follows:

[0029] Based on the active power of power generation, active power of load, and active power of boundary branches in the typical offline low-voltage network, the active power loss rate of each low-voltage network is calculated.

[0030] Based on the correspondence between online and offline devices, the active power generation and active power load of the medium and low voltage network are replaced by the measured data of the data acquisition and monitoring control system SCADA or the safety and stability control system, so as to obtain the active power corrected data of the medium and low voltage network and its active power imbalance.

[0031] Based on the active power loss rate of the medium and low voltage network and the active power of the associated online equivalent equipment, the active power loss of each medium and low voltage network spliced ​​together is estimated.

[0032] Based on the online equivalent equipment type and power direction, adjustable generator equipment set and adjustable load equipment set are selected from the active power correction medium and low voltage network data to obtain the active power adjustment measure set for each medium and low voltage network.

[0033] The active power imbalance of each medium and low voltage network is statistically analyzed and allocated to the active power adjustment measures set of each medium and low voltage network to obtain the active power adjusted data of the medium and low voltage network.

[0034] Based on the principle of equal power factor as in typical mode, the reactive power of generation and the reactive power of load in medium and low voltage networks are adjusted to obtain the medium and low voltage network data after power flow adjustment.

[0035] The formula for calculating the network loss rate of the medium and low voltage network is as follows:

[0036]

[0037] In the formula, k is the network loss rate of low-voltage network i in the typical offline mode, and P gn.i For the total active power generated by low-voltage network i in a typical offline mode, P ti.i For the total boundary branch active power of low-voltage network i in the offline typical mode (with the direction of flow to the low-voltage network as a reference), P ld.i The total active power of low-voltage network i in the offline typical mode is the load.

[0038] The formula for estimating active power loss after splicing medium and low voltage networks is as follows:

[0039]

[0040] In the formula, P lo ′ ss.i Let P be the estimated active power loss of medium- and low-voltage network i, k be the network loss rate of medium- and low-voltage network i, and P be the active power loss of network i. eq.i P represents the total active power of the associated online equivalent equipment in the medium- and low-voltage network i. g ′ n.i P represents the total active power generated after the measured data is connected to the medium- and low-voltage network i. l ′ d.i The total active power load after the measured data is accessed to the medium and low voltage network i.

[0041] The process for generating the active power adjustment measures set for the medium and low voltage network is as follows:

[0042] Generators and positive loads that are not connected to SCADA / safety control measured data in medium and low voltage network data are selected as candidate active power adjustment measures.

[0043] When the active power imbalance in the low-voltage network is greater than zero, generators with no room for downward adjustment and loads with no room for upward adjustment are removed from the candidate active power adjustment measures.

[0044] When the active power imbalance in the medium and low voltage network is less than zero, generators with no room for upward adjustment and loads with no room for downward adjustment are removed from the candidate active power adjustment measures.

[0045] The active power adjustment process of the medium and low voltage network is as follows:

[0046] When the online equivalent equipment is an equivalent generator and its active power is greater than zero, or when the online equivalent equipment is an equivalent load and its active power is less than zero, the active power imbalance is first distributed proportionally to the generators in the active power adjustment mechanism concentration according to the generator's adjustable space; if the generator's active power adjustment mechanism space is insufficient, the remaining active power imbalance is then distributed proportionally to the loads in the active power adjustment mechanism concentration; if the load's active power adjustment mechanism space is insufficient, the remaining active power imbalance is then treated as an equivalent load and connected to the online equivalent point.

[0047] When the online equivalent equipment is an equivalent generator and its active power is less than zero, or when the online equivalent equipment is an equivalent load and its active power is greater than zero, the active power imbalance is first proportionally distributed to the loads in the active power adjustment mechanism. If the load active power adjustment mechanism space is insufficient, the remaining active power imbalance is then proportionally distributed to the generators in the active power adjustment mechanism. If the generator active power adjustment mechanism space is insufficient, the remaining active power imbalance is then treated as an equivalent load and connected to the online equivalent point.

[0048] Secondly, the present invention also provides an online data splicing system for medium and low voltage networks based on power flow adjustment, comprising: a medium and low voltage network and its boundary branch determination module, a data correction and power flow adjustment module, a topology information modification module, and a data splicing module;

[0049] The medium and low voltage network and its boundary branch determination module is used to model offline equipment and identify offline substations based on offline typical mode data; based on the correspondence between online and offline substations, it identifies medium and low voltage networks based on offline typical mode data, and generates each medium and low voltage network and its boundary branch.

[0050] The data correction and power flow adjustment module is used to perform data correction and power flow adjustment on the medium and low voltage network based on the correspondence between online and offline devices and using measured data to obtain the medium and low voltage network data after power flow adjustment.

[0051] The topology information modification module is used to set the topology node number and topology island number of the main network side endpoint of the boundary branch of each medium and low voltage network to the topology node number and topology island number of the corresponding online equivalent equipment, and to shut down the corresponding online equivalent equipment.

[0052] The data splicing module combines the adjusted medium- and low-voltage network data with online data to obtain the full network data.

[0053] Furthermore, the medium and low voltage network and its boundary branch determination module specifically performs the following steps: based on the correspondence between offline and online power plants, it filters out the associated online equivalent equipment set of each offline power plant from the online data, wherein the online equivalent equipment includes online equivalent loads and online equivalent generators;

[0054] From the set of associated equipment in the offline substation, select AC line segments and transformer windings with the same highest voltage level as the set of associated online equivalent equipment as the set of associated boundary branch equipment for the offline substation;

[0055] The associated boundary branch equipment set and associated online equivalent equipment set of offline substations are sorted respectively; based on the sorting results, the associated boundary branch equipment and associated online equivalent equipment of offline substations are matched one by one to obtain the correspondence between boundary branch equipment and online equivalent equipment;

[0056] Based on offline data containing device models and topology relationships, starting from successfully matched boundary branch devices, a depth-first search algorithm is used to expand towards online unmodeled networks and low-voltage networks. Based on the nodes and branches that can be found through topology search, the medium and low-voltage networks are determined, and the boundary branches of the medium and low-voltage networks are identified.

[0057] Furthermore, the data correction and power flow adjustment module performs the following steps: based on the active power of power generation, active power of load, and active power of boundary branches of the low-voltage network in the offline typical mode, calculate the active power loss rate of each low-voltage network.

[0058] Based on the correspondence between online and offline devices, the active power generation and active power load of the medium and low voltage network are replaced by the measured data of the data acquisition and monitoring control system SCADA or the safety and stability control system, so as to obtain the active power corrected data of the medium and low voltage network and its active power imbalance.

[0059] Based on the active power loss rate of the medium and low voltage network and the active power of the associated online equivalent equipment, the active power loss of each medium and low voltage network spliced ​​together is estimated.

[0060] Based on the online equivalent equipment type and power direction, adjustable generator equipment set and adjustable load equipment set are selected from the active power correction medium and low voltage network data to obtain the active power adjustment measure set for each medium and low voltage network.

[0061] The active power imbalance of each medium and low voltage network is statistically analyzed and allocated to the active power adjustment measures set of each medium and low voltage network to obtain the active power adjusted data of the medium and low voltage network.

[0062] Based on the principle of equal power factor as in typical mode, the reactive power of generation and the reactive power of load in medium and low voltage networks are adjusted to obtain the medium and low voltage network data after power flow adjustment.

[0063] The present invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the method provided in any possible embodiment of the above technical solutions.

[0064] The beneficial technical effects achieved by this invention are as follows: This invention converts offline data into a set of offline substations and their associated equipment through offline device modeling and offline substation identification; it identifies various medium- and low-voltage networks and their boundary branches in the offline data through network topology analysis; based on the correspondence between online and offline devices, it corrects the node injection power of the medium- and low-voltage network using SCADA / safety control measured data, and obtains the medium- and low-voltage network data to be spliced ​​through power flow adjustment; by modifying the boundary branch topology information, it splices the power flow-adjusted medium- and low-voltage network data with the online data to generate full-network data that meets the requirements of online safety and stability analysis, thereby improving the completeness of the basic data for online safety and stability analysis and the accuracy of the calculation results of online safety analysis. Attached Figure Description

[0065] Figure 1 This is a flowchart of a method for online splicing of medium and low voltage network data based on power flow adjustment, provided in a specific embodiment.

[0066] Figure 2 This is a flowchart illustrating the generation process of an offline power plant and its associated equipment set, provided in a specific embodiment.

[0067] Figure 3 This is a flowchart of the generation process of medium and low voltage networks and their boundary branches provided in a specific embodiment.

[0068] Figure 4 This is a flowchart of medium and low voltage network data correction and power flow adjustment provided in a specific embodiment. Detailed Implementation

[0069] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0070] like Figure 1As shown, a method for online splicing of medium and low voltage network data based on power flow adjustment is performed according to the following steps:

[0071] Step 1: Based on offline typical data, perform offline equipment modeling and offline plant identification to generate offline plant and its associated equipment set.

[0072] like Figure 2 As shown, the process for generating the offline power plant and its associated equipment set is as follows:

[0073] 11) Based on the online device modeling and naming rules, convert the offline typical data into offline data containing device models and topological relationships;

[0074] 12) Take the small branches (i.e., switch branches), series capacitors, series reactors and transformer windings in the offline data as branches, and the bus as nodes to perform topology analysis to obtain the topology island and the topology nodes it contains.

[0075] 13) Mark each topology island as an offline plant, and use the associated device set of all topology nodes in the topology island as the associated device set of the corresponding offline plant.

[0076] Step 2: Based on the correspondence between online and offline power plants, identify the medium and low voltage networks for typical offline methods to obtain each medium and low voltage network and its boundary branches.

[0077] like Figure 3 As shown, the generation process of the medium- and low-voltage network and its boundary branches is as follows:

[0078] 21) Based on the correspondence between offline and online power plants, filter out the associated online equivalent equipment set for each offline power plant from the online data; the online equivalent equipment includes online equivalent loads and online equivalent generators;

[0079] 22) Select AC line segments and transformer windings with the same highest voltage level as the associated online equivalent equipment set from the associated equipment set of the offline substation as the associated boundary branch equipment set of the offline substation;

[0080] 23) Sort the associated boundary branch equipment set and associated online equivalent equipment set of the offline power station respectively to obtain the associated boundary branch equipment sorting table and associated online equivalent equipment sorting table of the offline power station;

[0081] The process for generating the boundary branch equipment sorting table and the online equivalent equipment sorting table is as follows:

[0082] For boundary branch equipment, firstly, it is sorted according to the priority order of "three-winding transformers first, two-winding transformers second, and AC line segments last". Then, boundary branch equipment of the same priority is sorted according to the voltage level from high to low. Finally, boundary branch equipment of the same voltage level is sorted according to the rated capacity / rated current from large to small, forming a boundary branch equipment sorting table.

[0083] For online equivalent equipment, the priority order is first set according to the order of "three-winding transformer equivalent equipment first, two-winding transformer equivalent equipment second, and AC line segment equivalent equipment last". Then, online equivalent equipment of the same priority is sorted in the order of voltage level from high to low. Finally, online equivalent equipment of the same voltage level is sorted in the order of rated capacity / rated current from large to small, forming an online equivalent equipment sorting table.

[0084] 24) Match the associated boundary branch equipment and associated online equivalent equipment of the offline plant one by one to obtain the correspondence between the boundary branch equipment and the online equivalent equipment;

[0085] The matching strategy between the boundary branch equipment and the online equivalent equipment is as follows:

[0086] First, for boundary branch equipment and online equivalent equipment, a matching process is performed based on the principle that the equipment type, voltage level, and rated current / rated capacity are all the same.

[0087] Next, for the remaining unmatched boundary branch equipment and online equivalent equipment, a second matching process is performed based on the principle that the equipment type and voltage are the same.

[0088] Then, for the remaining unmatched boundary branch equipment and online equivalent equipment, three matching processes are performed according to the principle of the same equipment type;

[0089] 25) Based on offline data containing device models and topology relationships, starting from the successfully matched boundary branch devices, a depth-first search algorithm is used to expand towards the online unmodeled network and low-voltage network, and the nodes and branches that can be topologically searched are used as the associated low-voltage network data of the boundary branches.

[0090] Step 3: Based on the correspondence between online and offline devices, use SCADA / security control measured data to correct the data and adjust the power flow of the medium and low voltage network, and obtain the medium and low voltage network data after power flow adjustment.

[0091] like Figure 4 As shown, the process of data correction and power flow adjustment in the medium and low voltage network is as follows:

[0092] 31) Based on the active power generation, active power load, and active power of boundary branches of the low-voltage network in the offline typical mode, calculate the active power loss rate of each low-voltage network.

[0093] The formula for calculating the network loss rate of the medium and low voltage network is as follows:

[0094]

[0095] In the formula, k is the network loss rate of low-voltage network i in the typical offline mode, and P gn.i For the total active power generated by low-voltage network i in a typical offline mode, P ti.i For the total boundary branch active power of low-voltage network i in the offline typical mode (with the direction of flow to the low-voltage network as a reference), P ld.i The total active power of low-voltage network i in the offline typical mode is the load.

[0096] 32) Based on the correspondence between online and offline devices, replace the generator active power and load active power of the medium and low voltage network with SCADA / safety control measured data to obtain the active power corrected data of the medium and low voltage network and its active power imbalance.

[0097] 33) Based on the active power loss rate of the medium and low voltage network and the active power of the associated online equivalent equipment, estimate the active power loss of each medium and low voltage network after splicing.

[0098] The formula for estimating active power loss after splicing medium and low voltage networks is as follows:

[0099]

[0100] In the formula, P′ loss.i P is the estimated active power loss of medium- and low-voltage network i. eq.i P′ represents the total active power of the associated online equivalent equipment in the medium- and low-voltage network i. gn.i P′ represents the total active power generated after the measured data is connected to the medium- and low-voltage network i. ld.i The total active power load after the measured data is accessed to the medium and low voltage network i.

[0101] 34) Based on the online equivalent equipment type and power direction, select the adjustable generator equipment set and adjustable load equipment set from the active power correction medium and low voltage network data to obtain the active power adjustment measures set for each medium and low voltage network.

[0102] The process for generating the active power adjustment measures set for the medium and low voltage network is as follows:

[0103] Generators and positive loads that are not connected to SCADA / safety control measured data in medium and low voltage network data are selected as candidate active power adjustment measures.

[0104] When the active power imbalance in the low-voltage network is greater than zero, generators with no room for downward adjustment and loads with no room for upward adjustment are removed from the candidate active power adjustment measures.

[0105] When the active power imbalance in the medium and low voltage network is less than zero, generators with no room for upward adjustment and loads with no room for downward adjustment are removed from the candidate active power adjustment measures.

[0106] 35) Calculate the active power imbalance of each medium and low voltage network, distribute it to the active power adjustment measures set of each medium and low voltage network, and obtain the active power adjusted medium and low voltage network data.

[0107] The active power adjustment process of the medium and low voltage network is as follows:

[0108] When the online equivalent equipment is an equivalent generator and its active power is greater than zero, or when the online equivalent equipment is an equivalent load and its active power is less than zero, the active power imbalance is first distributed proportionally to the generators in the active power adjustment mechanism concentration according to the generator's adjustable space; if the generator's active power adjustment mechanism space is insufficient, the remaining active power imbalance is then distributed proportionally to the loads in the active power adjustment mechanism concentration; if the load's active power adjustment mechanism space is insufficient, the remaining active power imbalance is then treated as an equivalent load and connected to the online equivalent point.

[0109] When the online equivalent equipment is an equivalent generator and its active power is less than zero, or when the online equivalent equipment is an equivalent load and its active power is greater than zero, the active power imbalance is first proportionally distributed to the loads in the active power adjustment mechanism. If the load active power adjustment mechanism space is insufficient, the remaining active power imbalance is then proportionally distributed to the generators in the active power adjustment mechanism. If the generator active power adjustment mechanism space is insufficient, the remaining active power imbalance is then treated as an equivalent load and connected to the online equivalent point.

[0110] 36) Adjust the power generation reactive power and load reactive power of the medium and low voltage network according to the principle of equal power factor as in the typical mode to obtain the medium and low voltage network data after power flow adjustment.

[0111] Step 4: Modify the topology information of the boundary branches of the medium and low voltage network. The modification method is to set the topology node number and topology island number of the main network side endpoint of each boundary branch of the medium and low voltage network to the topology node number and topology island number of the corresponding online equivalent equipment.

[0112] The corresponding online equivalent equipment is shut down; the medium and low voltage network data after power flow adjustment and the online data are combined to obtain the full network data.

[0113] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0114] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0115] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0116] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0117] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A method for online splicing of medium and low voltage network data based on power flow adjustment, characterized in that, include: Offline equipment modeling and offline plant identification are based on offline typical data. Based on the correspondence between online and offline power plants, medium and low voltage networks are identified in the data of typical offline methods, and each medium and low voltage network and its boundary branches are generated; including: according to the correspondence between offline and online power plants, the associated online equivalent equipment set of each offline power plant is selected from the online data, wherein the online equivalent equipment includes online equivalent load and online equivalent generator; From the set of associated equipment in the offline substation, select AC line segments and transformer windings with the same highest voltage level as the set of associated online equivalent equipment as the set of associated boundary branch equipment for the offline substation; The associated boundary branch equipment set and associated online equivalent equipment set of offline substations are sorted respectively; based on the sorting results, the associated boundary branch equipment and associated online equivalent equipment of offline substations are matched one by one to obtain the correspondence between boundary branch equipment and online equivalent equipment; Based on offline data containing device models and topology relationships, starting from successfully matched boundary branch devices, a depth-first search algorithm is used to expand towards online unmodeled networks and low-voltage networks. Based on the nodes and branches that can be found through topology search, the medium and low-voltage networks are determined, and the boundary branches of the medium and low-voltage networks are also determined. Based on the correspondence between online and offline devices, measured data is used to correct and adjust the power flow of medium- and low-voltage networks, resulting in power flow-adjusted medium- and low-voltage network data. The data correction and power flow adjustment processes for each medium- and low-voltage network include: Based on the active power of power generation, active power of load, and active power of boundary branches in the typical offline low-voltage network, the active power loss rate of each low-voltage network is calculated. Based on the correspondence between online and offline devices, the active power generation and active power load of the medium and low voltage network are replaced by the measured data of the data acquisition and monitoring control system SCADA or the safety and stability control system, so as to obtain the active power corrected data of the medium and low voltage network and its active power imbalance. Based on the active power loss rate of the medium and low voltage network and the active power of the associated online equivalent equipment, the active power loss of each medium and low voltage network spliced ​​together is estimated. Based on the online equivalent equipment type and power direction, adjustable generator equipment set and adjustable load equipment set are selected from the active power correction medium and low voltage network data to obtain the active power adjustment measure set for each medium and low voltage network. The active power imbalance of each medium and low voltage network is statistically analyzed and allocated to the active power adjustment measures set of each medium and low voltage network to obtain the active power adjusted data of the medium and low voltage network. Based on the principle of equal power factor as in typical mode, the reactive power of generation and the reactive power of load in medium and low voltage networks are adjusted to obtain the medium and low voltage network data after power flow adjustment. Set the topology node number and topology island number of the main network side endpoint of the boundary branch of each medium and low voltage network to the topology node number and topology island number of the corresponding online equivalent equipment, and shut down the corresponding online equivalent equipment; combine the medium and low voltage network data after power flow adjustment with the online data to obtain the whole network data.

2. The online data splicing method for medium and low voltage networks based on power flow adjustment according to claim 1, characterized in that: Methods for sorting the associated boundary branch equipment set and associated online equivalent equipment set of offline substations include: For boundary branch equipment, firstly, it is sorted according to the priority order of "three-winding transformers first, two-winding transformers second, and AC line segments last". Then, boundary branch equipment of the same priority is sorted according to the voltage level from high to low. Finally, boundary branch equipment of the same voltage level is sorted according to the rated capacity or rated current from large to small, forming a boundary branch equipment sorting table. For online equivalent equipment, the priority order is first set according to "three-winding transformer equivalent equipment first, two-winding transformer equivalent equipment second, and AC line segment equivalent equipment last". Then, online equivalent equipment of the same priority is sorted in the second level according to voltage level from high to low. Finally, online equivalent equipment of the same voltage level is sorted in the third level according to rated capacity or rated current from large to small, forming an online equivalent equipment sorting table.

3. The online data splicing method for medium and low voltage networks based on power flow adjustment according to claim 1, characterized in that: The process of generating the associated equipment set for offline power plants includes: Based on online device modeling and naming rules, offline typical data is converted into offline data containing device models and topological relationships; The switch branches, series capacitors, series reactors and transformer windings in the offline data are taken as branches, and the bus is taken as a node for topology analysis to obtain the topology island and the topology nodes it contains. Each topology island is marked as an offline plant, and the set of associated devices of all topology nodes within the topology island is taken as the set of associated devices of the corresponding offline plant.

4. The online data splicing method for medium and low voltage networks based on power flow adjustment according to claim 1, characterized in that: Matching strategies for boundary branch equipment and online equivalent equipment include: For boundary branch equipment and online equivalent equipment, a single matching process shall be carried out based on the principle that the equipment type, voltage level, rated current or rated capacity are the same. For the remaining unmatched boundary branch equipment and online equivalent equipment, a second matching process will be conducted based on the principle that the equipment type and voltage are the same. For the remaining unmatched boundary branch equipment and online equivalent equipment, three matching processes will be conducted based on the principle that the equipment types are the same. Unmatched boundary branches are removed from the associated boundary branch equipment of offline power plants, and unmatched online equivalent equipment is removed from the associated online equivalent equipment of offline power plants.

5. The online data splicing method for medium and low voltage networks based on power flow adjustment according to claim 1, characterized in that: The formula for calculating the network loss rate of medium and low voltage networks is as follows: （1） In the formula, k represents the low-voltage network in the typical offline mode. Network loss rate, For offline typical low-voltage networks Total active power generation, For offline typical low-voltage networks The total boundary branch active power with reference to the direction of flow to the medium and low voltage network. For offline typical low-voltage networks The total load is active power.

6. The online data splicing method for medium and low voltage networks based on power flow adjustment according to claim 1, characterized in that: The formula for estimating active power loss after splicing medium and low voltage networks is as follows: （2） In the formula, For medium and low voltage networks The estimated active power loss of the network, where k is the value for medium and low voltage networks. Network loss rate, For medium and low voltage networks The total active power of the associated online equivalent equipment, For medium and low voltage networks Total active power generation after incorporating measured data For medium and low voltage networks The total active power load after accessing the measured data.

7. The online data splicing method for medium and low voltage networks based on power flow adjustment according to claim 1, characterized in that: The process of generating the active power regulation measures set for medium and low voltage networks includes: Generators and positive loads in the medium and low voltage network data that are not connected to the data acquisition and monitoring control system SCADA or the safety and stability control system are used as the candidate active power adjustment measures set. When the active power imbalance in the low-voltage network is greater than zero, generators with no room for downward adjustment and loads with no room for upward adjustment are removed from the candidate active power adjustment measures. When the active power imbalance in the medium and low voltage network is less than zero, generators with no room for upward adjustment and loads with no room for downward adjustment are removed from the candidate active power adjustment measures. The final set of candidate active power adjustment measures will be used as the active power adjustment measure set for medium and low voltage networks.

8. The online data splicing method for medium and low voltage networks based on power flow adjustment according to claim 1, characterized in that: The active power adjustment process of medium and low voltage networks is as follows: When the online equivalent equipment is an equivalent generator and its active power is greater than zero, or when the online equivalent equipment is an equivalent load and its active power is less than zero, the active power imbalance is first distributed proportionally to the generators in the active power adjustment mechanism. If the generator active power adjustment mechanism is insufficient, the remaining active power imbalance is then distributed proportionally to the loads in the active power adjustment mechanism. When there is insufficient space for active power adjustment measures, the remaining active power imbalance is then treated as an equivalent load and attached to the online equivalent point. When the online equivalent equipment is an equivalent generator and its active power is less than zero, or when the online equivalent equipment is an equivalent load and its active power is greater than zero, the active power imbalance is first proportionally distributed to the loads where the active power adjustment measures are concentrated. When the space for active power adjustment measures is insufficient, the remaining active power imbalance is distributed proportionally to the generators with concentrated active power adjustment measures according to the generator's adjustable space; when the space for generator active power measures is insufficient, the remaining active power imbalance is treated as an equivalent load and connected to the online equivalent point.

9. A medium- and low-voltage network data online splicing system based on power flow adjustment, characterized in that, include: The module includes a medium- and low-voltage network and its boundary branch determination module, a data correction and power flow adjustment module, a topology information modification module, and a data splicing module. The medium- and low-voltage network and its boundary branch determination module is used to model offline equipment and identify offline substations based on offline typical mode data; based on the correspondence between online and offline substations, it identifies medium- and low-voltage networks in the offline typical mode data to generate various medium- and low-voltage networks and their boundary branches; the medium- and low-voltage network and its boundary branch determination module specifically performs the following steps: according to the correspondence between offline and online substations, it filters out the associated online equivalent equipment set of each offline substation from the online data, wherein the online equivalent equipment includes online equivalent loads and online equivalent generators; From the set of associated equipment in the offline substation, select AC line segments and transformer windings with the same highest voltage level as the set of associated online equivalent equipment as the set of associated boundary branch equipment for the offline substation; Sort the associated boundary branch equipment set and associated online equivalent equipment set of offline substations respectively; Based on the sorting results, the associated boundary branch equipment and associated online equivalent equipment of offline power plants are matched one by one to obtain the correspondence between boundary branch equipment and online equivalent equipment; Based on offline data containing device models and topology relationships, starting from successfully matched boundary branch devices, a depth-first search algorithm is used to expand towards online unmodeled networks and low-voltage networks. Based on the nodes and branches that can be found through topology search, the medium and low-voltage networks are determined, and the boundary branches of the medium and low-voltage networks are also determined. The data correction and power flow adjustment module is used to perform data correction and power flow adjustment on the medium and low voltage network based on the correspondence between online and offline devices and using measured data to obtain the power flow adjusted medium and low voltage network data. The data correction and power flow adjustment module performs the following steps: calculate the active power loss rate of each medium and low voltage network based on the power generation active power, load active power and boundary branch active power of the offline typical medium and low voltage network. Based on the correspondence between online and offline devices, the active power generation and active power load of the medium and low voltage network are replaced by the measured data of the data acquisition and monitoring control system SCADA or the safety and stability control system, so as to obtain the active power corrected data of the medium and low voltage network and its active power imbalance. Based on the active power loss rate of the medium and low voltage network and the active power of the associated online equivalent equipment, the active power loss of each medium and low voltage network spliced ​​together is estimated. Based on the online equivalent equipment type and power direction, adjustable generator equipment set and adjustable load equipment set are selected from the active power correction medium and low voltage network data to obtain the active power adjustment measure set for each medium and low voltage network. The active power imbalance of each medium and low voltage network is statistically analyzed and allocated to the active power adjustment measures set of each medium and low voltage network to obtain the active power adjusted data of the medium and low voltage network. Based on the principle of equal power factor as in typical mode, the reactive power of generation and the reactive power of load in medium and low voltage networks are adjusted to obtain the medium and low voltage network data after power flow adjustment. The topology information modification module is used to set the topology node number and topology island number of the main network side endpoint of the boundary branch of each medium and low voltage network to the topology node number and topology island number of the corresponding online equivalent equipment, and to shut down the corresponding online equivalent equipment. The data splicing module combines the adjusted medium- and low-voltage network data with online data to obtain the full network data.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as claimed in any one of claims 1 to 8.

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