Distribution network system protection configuration method and system in whole county photovoltaic power supply scene

Abstract

The invention discloses a distribution network system protection configuration method and system in a whole county photovoltaic power supply scene. The method comprises the steps of obtaining first photovoltaic access information in a target range, and performing first preprocessing on the first photovoltaic access information; establishing a first network according to the first preprocessing result, wherein the first network is used for fault detection and fault isolation; and recovering power supply of the plurality of areas after fault isolation is completed, and adjusting the setting value of the protection device in real time according to the operation data of the plurality of areas. Differential protection configuration for different permeability areas is achieved, distribution network faults can be accurately detected, fault areas can be rapidly isolated, normal power supply of non-fault areas is prevented from being affected, the setting value of a protection device can be adjusted in real time according to a power flow optimization algorithm, and the problems of delay and misoperation in a traditional protection strategy are solved.

Description

Technical Field

[0001] The present invention relates to the field of distribution network protection technology, and in particular to a distribution network system protection configuration method and system in a whole-county photovoltaic power supply scenario. Background Art

[0002] With the rapid development of renewable energy technology, photovoltaic power generation, as a green and low-carbon energy form, has been widely used around the world. Especially in my country, with the gradual strengthening of national support for renewable energy policies and subsidies, the scale of photovoltaic power generation systems has continued to expand, especially at the county and regional levels, where distributed access has been gradually realized.

[0003] In recent years, the proportion of photovoltaic power generation in the power grid has increased year by year, especially the promotion of photovoltaic power supply scenarios in the whole county. In this process, the impact of photovoltaic power on the distribution network has gradually emerged. The access of photovoltaic systems has changed the power supply mode and power flow of traditional power systems, making the power flow of distribution networks more complex and dynamic.

[0004] Therefore, how to efficiently and accurately configure the protection measures of the distribution network to cope with the challenges of grid operation after large-scale photovoltaic access has become an urgent task in distribution network management. Summary of the invention

[0005] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0006] In view of the above existing problems, the present invention is proposed.

[0007] Therefore, the present invention provides a distribution network system protection configuration method and system in a whole-county photovoltaic power supply scenario, which can solve the problems mentioned in the background technology.

[0008] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0009] In a first aspect, the present invention provides a method for configuring distribution network system protection in a whole-county photovoltaic power supply scenario, comprising:

[0010] Acquire first photovoltaic access information within a target range, and perform first preprocessing on the first photovoltaic access information;

[0011] Establishing a first network according to the first preprocessing result, wherein the first network is used for fault detection and fault isolation;

[0012] Restore power supply to several areas after fault isolation is completed, and adjust the setting values ​​of protection devices in real time based on the operating data of several areas.

[0013] As a preferred solution of the distribution network system protection configuration method in the whole-county photovoltaic power supply scenario described in the present invention, wherein: the first preprocessing at least includes:

[0014] Acquire a first penetration rate according to the first photovoltaic access information;

[0015] Regional division is performed according to the first permeability combined with a first regional division criterion.

[0016] As a preferred solution of the distribution network system protection configuration method in the whole-county photovoltaic power supply scenario described in the present invention, wherein: the establishment of the first network according to the first preprocessing result includes:

[0017] Obtaining first target parameters and second target parameters of target key points in a plurality of regions after region division;

[0018] Establishing a network status matrix for a plurality of areas according to the first target parameter and the second target parameter;

[0019] A first integration is performed on the network status matrices of the plurality of regions to obtain a first network.

[0020] As a preferred solution of the distribution network system protection configuration method in the whole-county photovoltaic power supply scenario described in the present invention, the power supply of several areas after the fault isolation is completed includes:

[0021] Obtaining load importance in a plurality of areas, and performing a first priority sorting on the loads in the plurality of areas according to the load importance;

[0022] The power supply to the corresponding areas is restored in order according to the first priority ranking.

[0023] As a preferred solution of the distribution network system protection configuration method in the whole-county photovoltaic power supply scenario described in the present invention, wherein: the real-time adjustment of the protection device setting value according to the operating data of several regions includes:

[0024] Calculating a first set of setting values ​​for each protection line in the area one by one according to a number of area operation data;

[0025] The first set of setting values ​​is sent to the corresponding protection device, and the setting values ​​of the protection device are adjusted in real time.

[0026] As a preferred solution of the distribution network system protection configuration method in the whole-county photovoltaic power supply scenario described in the present invention, wherein: obtaining the first penetration rate according to the first photovoltaic access information includes:

[0027] Acquire the first photovoltaic access information of the photovoltaic access point within the target range;

[0028] Acquire the preliminary power generation capacity and regional total load capacity of the photovoltaic access points within the target range according to the first photovoltaic access information;

[0029] The first penetration rate is calculated according to the preliminary power generation capacity of the photovoltaic access points within the target range and the total load capacity of the region.

[0030] As a preferred solution of the distribution network system protection configuration method in the whole-county photovoltaic power supply scenario described in the present invention, the first area division criteria include:

[0031] Setting a first partition threshold and a second partition threshold;

[0032] Establishing a first area division criterion based on the first division threshold and the second division threshold;

[0033] Regional division is performed according to the first permeability combined with a first regional division criterion.

[0034] In a second aspect, the present invention provides a distribution network system protection configuration system in a whole-county photovoltaic power supply scenario, comprising:

[0035] A data acquisition and processing module, used for acquiring first photovoltaic access information within a target range, and performing first preprocessing on the first photovoltaic access information;

[0036] A network establishing module, used to establish a first network according to the first preprocessing result, wherein the first network is used for fault detection and fault isolation;

[0037] The setting module is used to restore power supply to several areas after fault isolation is completed, and to adjust the setting values ​​of protection devices in real time according to the operating data of several areas.

[0038] In a third aspect, the present invention provides a computer device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the above-mentioned method when executing the computer program.

[0039] In a fourth aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program implements the steps of the method described above when executed by a processor.

[0040] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention proposes a distribution network system protection configuration method and system in the scenario of photovoltaic power supply in the whole county, obtains the first photovoltaic access information within the target range, and performs the first preprocessing on the first photovoltaic access information; establishes the first network according to the first preprocessing result, and the first network is used for fault detection and fault isolation; restores the power supply of several areas after the fault isolation is completed, and adjusts the setting value of the protection device in real time according to the operation data of several areas. Differentiated protection configuration for different penetration areas is realized, distribution network faults can be accurately detected, and the fault area can be quickly isolated to avoid affecting the normal power supply of non-fault areas. The setting value of the protection device can be adjusted in real time according to the flow optimization algorithm, and the performance of the distribution network protection device can be optimized to make it more adaptable to the fluctuation of the power grid after the photovoltaic power supply is connected, ensuring efficient operation in a complex photovoltaic power generation environment, and being able to respond to changes in the power grid status in a timely manner, avoiding the delay and false operation problems in traditional protection strategies. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0042] Figure 1 A method flow chart of a distribution network system protection configuration method and system in a whole-county photovoltaic power supply scenario provided by an embodiment of the present invention;

[0043] Figure 2 An internal structure diagram of a computer device of a distribution network system protection configuration method and system in a whole-county photovoltaic power supply scenario provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0044] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0045] Example 1

[0046] Reference Figure 1-Figure 2 , which is the first embodiment of the present invention, and provides a distribution network system protection configuration method and system in a whole-county photovoltaic power supply scenario, including:

[0047] There are some problems in the existing related technologies. For example, when facing large-scale photovoltaic power access, the traditional distribution network protection configuration method is often unable to effectively cope with the dynamic changes in the operation of the power grid, resulting in the setting value of the protection device being difficult to adapt to the actual operating conditions, thus affecting the stability and reliability of the power grid.

[0048] This application provides a method that can effectively solve the above-mentioned problems. Next, we will combine multiple embodiments to explain in detail how to implement the distribution network system protection configuration method in the whole county photovoltaic power supply scenario;

[0049] Figure 1 A method flow chart of a distribution network system protection configuration method and system in a whole-county photovoltaic power supply scenario is shown, including:

[0050] S101, acquiring first photovoltaic access information within a target range, and performing first preprocessing on the first photovoltaic access information;

[0051] In the embodiment of the present application, the first preprocessing at least includes:

[0052] Acquire a first penetration rate according to the first photovoltaic access information;

[0053] Regional division is performed according to the first permeability combined with a first regional division criterion.

[0054] In an optional embodiment, the first photovoltaic access information may include but is not limited to the access location, access capacity, access mode, voltage level of the access point, etc. of the photovoltaic power source, which is crucial for the subsequent network status matrix establishment and fault detection.

[0055] In another optional embodiment, after obtaining the first photovoltaic access information, it is crucial to perform a first preprocessing step. The purpose of the preprocessing is to better understand and utilize the information, so as to facilitate subsequent network status analysis and formulation of fault isolation strategies.

[0056] In another optional embodiment, different calculation models and algorithms may be used to obtain the first penetration rate according to different first photovoltaic access information. For example, a statistical analysis method based on historical data may be used, or a dynamic simulation method based on real-time data may be used. Selecting a suitable calculation model and algorithm can ensure that the calculation result of the penetration rate is both accurate and real-time, thereby providing reliable data support for distribution network protection configuration.

[0057] It should be noted that obtaining the first permeability is a key step in the preprocessing process. Permeability refers to the degree of access of photovoltaic power sources to the distribution network, which directly affects the power flow distribution and protection strategy setting of the distribution network. By calculating the permeability, the impact of photovoltaic power sources on the distribution network can be more accurately evaluated, providing a scientific basis for subsequent protection configuration.

[0058] In the embodiment of the present application, the first photovoltaic access information is the preliminary voltage and line impedance and short-circuit fault current of the photovoltaic access point;

[0059] In the embodiment of the present application, acquiring the first penetration rate according to the first photovoltaic access information includes:

[0060] Acquire the first photovoltaic access information of the photovoltaic access point within the target range;

[0061] Acquire the preliminary power generation capacity and regional total load capacity of the photovoltaic access points within the target range according to the first photovoltaic access information;

[0062] The first penetration rate is calculated according to the preliminary power generation capacity of the photovoltaic access points within the target range and the total load capacity of the region.

[0063] Exemplarily, a synchronized phasor measurement unit is used to collect preliminary voltage, line impedance and short-circuit fault current of a photovoltaic access point, and a SCADA (Supervisory Control and Data Acquisition) system is used to collect preliminary power generation capacity and regional total load capacity of each photovoltaic access point. The collected data is preprocessed, photovoltaic access points and power generation capacity are sorted according to geographical location and administrative divisions, and the regional total load is matched by division. The photovoltaic penetration rate Z of each region is calculated according to the total power generation capacity of the photovoltaic access points in the region and the regional total load capacity:

[0064]

[0065] In the formula, G1 is the power generation capacity of the photovoltaic access point, and G2 is the total load capacity of the region;

[0066] In an optional embodiment, the first regional division criterion may use geographic information system (GIS) technology to ensure the accuracy and practicality of regional division. Through GIS technology, the geographical location information of the photovoltaic access point can be superimposed on the regional load distribution layer, so as to achieve accurate matching of the photovoltaic access point and the load. In addition, GIS technology can also help identify and analyze the load characteristics of different areas, such as residential areas, commercial areas and industrial areas, so as to facilitate the subsequent distribution network protection configuration and optimization.

[0067] In another alternative embodiment, the first area division criterion can also use an existing optimization algorithm based on load characteristics to further improve the operating efficiency of the distribution network system. This algorithm dynamically adjusts the power generation capacity allocation of the PV access points by analyzing the load characteristics of different areas, such as the load changes during peak and valley periods and seasonal load fluctuations. For example, in residential areas, considering the peak and valley characteristics of residential electricity consumption, PV power sources that can provide stable output can be preferentially configured, while in commercial areas, more PV power sources with fast response can be configured to meet the fluctuating demand for commercial electricity.

[0068] In another alternative embodiment, the first area division criterion can also preset the division criterion, and the threshold division can be performed according to the actual needs of the user.

[0069] In the embodiment of the present application, the first area division criterion includes:

[0070] Set a first division threshold and a second division threshold;

[0071] Establish a first area division criterion based on the first division threshold and the second division threshold;

[0072] Perform area division according to the first penetration rate in combination with the first area division criterion.

[0073] Exemplarily, summarize the PV penetration rate results calculated for each area to generate a penetration rate distribution table. By collecting long-term power load data and PV power generation data, use statistical methods to evaluate the impact of different PV penetration rates on the operation of the power grid. Set the penetration rate thresholds as A and B, where A < B. If the penetration rate is less than or equal to threshold A, it is a low penetration area; if the penetration rate is greater than threshold A and less than or greater than threshold B, it is a medium penetration area; if the penetration rate is greater than threshold B, it is a high penetration area;

[0074] In an alternative embodiment, use GIS to visualize the penetration rate results and generate an area penetration rate distribution map;

[0075] In an alternative embodiment, the area penetration rate distribution map refers to color-coding the penetration rate, with low penetration in green, medium penetration in yellow, and high penetration in red, and marking each PV access point and power generation capacity on the map;

[0076] In an alternative embodiment, assign a primary agent node and a standby agent to each area. The primary agent and the standby agent communicate with low latency through the MQTT protocol. Assign a unique identifier to each agent node and record the PV access points and load information under its jurisdiction;

[0077] In an alternative embodiment, the primary agent is responsible for data collection of all PV access points and load nodes within the partition, and the standby agent is responsible for taking over the tasks when the primary agent fails.

[0078] It should be noted that by calculating the PV penetration rate of each region, it is possible to identify which regions have a greater impact on the power grid with PV power generation. High penetration areas may cause frequent fluctuations in the power grid or voltage instability, so different protection strategies and load dispatching methods are needed. Through accurate penetration rate calculation, regions with different PV penetration rates can be optimized and managed, and power generation resources can be dispatched in a targeted manner to avoid load fluctuations caused by excessive or insufficient PV power generation. Real-time monitoring and zoning management of PV penetration rates help the system to identify vulnerable links in the power grid in a timely manner, so as to carry out targeted enhancements and improve the safety and stability of the distribution network. Through GIS visualization of the penetration rate distribution map, it is possible to clearly see the impact of PV power generation in different regions on the distribution network, which helps power dispatchers to make decisions quickly and implement flexible dispatching and protection measures. Distribution network managers can adjust protection strategies, load dispatching and energy storage management according to the characteristics of different penetration rate areas (such as low penetration, medium penetration and high penetration), thereby improving overall operation efficiency. The penetration rate distribution map provides detailed spatial data, allowing power system operators to rationally plan resources and facilities according to regional characteristics and energy demand, further optimize power grid operation, and ensure efficient operation of data collection, processing and coordination by allocating primary and backup agents to each region. The main agent is responsible for data collection and protection coordination of all photovoltaic access points and load nodes in the area. The backup agent ensures that it takes over the task when the main agent fails, thereby improving the reliability of the system. The main agent and the backup agent communicate in real time through the low-latency MQTT protocol. When a failure or abnormal situation occurs, the backup agent can quickly take over to ensure the continuous operation of the power grid in the entire area. The low-latency communication between the main agent and the backup agent is achieved through the MQTT protocol, ensuring that the operation and data collection of each agent node can reflect the operation status of the power grid in real time, greatly improving the efficiency and accuracy of data transmission. The setting of the backup agent ensures that when the main agent fails or fails, the backup agent can quickly take over the task to prevent data loss or interruption of the power grid protection function, thereby improving the stability and reliability of the system.

[0079] S102, establishing a first network according to the first preprocessing result, where the first network is used for fault detection and fault isolation;

[0080] In an embodiment of the present application, establishing the first network according to the first preprocessing result includes:

[0081] Obtaining first target parameters and second target parameters of target key points in a plurality of regions after region division;

[0082] Establishing a network status matrix for a plurality of areas according to the first target parameter and the second target parameter;

[0083] A first integration is performed on the network status matrices of the plurality of regions to obtain a first network.

[0084] In an optional embodiment, the first target parameter and the second target parameter of the target key point can be selected according to the actual needs of relevant technical personnel. For example, when selecting the first target parameter, the voltage, current and other electrical quantities of the key point can be considered. These parameters are directly related to the stable operation of the power grid. For example, the fluctuation range of voltage and the continuous load capacity of current are important indicators for evaluating the state of the power grid.

[0085] In another optional embodiment, the second target parameter may focus on environmental factors and equipment status, such as temperature, humidity, equipment aging, etc. Although these factors do not directly reflect electrical quantities, they have a significant impact on the long-term stable operation of power grid equipment.

[0086] In another optional embodiment, when establishing the network status matrix, these parameters are comprehensively analyzed to form a multi-dimensional data model that can fully reflect the state of the power grid. Through the integration of the matrix, potential risk points in the power grid can be more accurately identified, thereby providing a scientific basis for fault detection and isolation.

[0087] In the embodiment of the present application, the real-time node voltage, current, phase angle and short-circuit current (i.e., the first target parameter) are collected at the key nodes in each partition, and the real-time regional total load and the power generation capacity of each photovoltaic access point (i.e., the second target parameter) of each partition are collected;

[0088] In an optional embodiment, the key nodes may be substations, transformers, important load access points, etc., which are essential for the stable operation of the power grid. By real-time monitoring of the parameters of these key nodes, abnormal conditions in the operation of the power grid can be discovered in a timely manner, providing accurate data support for fault detection and isolation.

[0089] In the embodiment of the present application, photovoltaic access points and load nodes are selected as key nodes.

[0090] In an optional embodiment, the network state matrix can be designed in different ways. For example, a graph theory-based method can be used to abstract the nodes in the power grid and the lines connecting them into vertices and edges in the graph, thereby constructing a network state matrix reflecting the topological structure of the power grid. The matrix can not only represent the electrical connection relationship between nodes, but also include the electrical parameters of the nodes, such as voltage, current, etc., to provide a basis for subsequent fault analysis and isolation.

[0091] In another optional embodiment, the network state matrix can also be optimized by an algorithm based on machine learning. Using historical data to train the model, the network state matrix can dynamically adjust its parameters to adapt to changes in the operating state of the power grid. This method can improve the accuracy of fault prediction, reduce false positives and false negatives, and thus improve the reliability and efficiency of the entire distribution network system.

[0092] In another optional embodiment, the design of the network status matrix can also be combined with an expert system to use expert knowledge to analyze and judge abnormal conditions in the operation of the power grid. By combining the expert system with the machine learning algorithm, intelligent monitoring and management of the power grid status can be achieved, further improving the efficiency of fault detection and isolation.

[0093] It should be noted that the construction and optimization of the network status matrix is ​​an ongoing process. It is necessary to continuously collect and analyze grid operation data to ensure that the matrix can accurately reflect the real-time status of the grid. At the same time, it is also necessary to regularly check and adjust the matrix to adapt to changes in grid structure and operation mode.

[0094] In the embodiment of the present application, the following specific steps are used to establish the first network:

[0095] In the master agent node, the collected data is preprocessed and then integrated to form a partitioned raw data matrix;

[0096] Furthermore, within each partition, the voltage optimization objective function of each partition is constructed based on the node voltage data in the partition original data matrix:

[0097] F h (U) = ∑ i∈a [(U i -U ref ) 2 +β·Var(U i )]

[0098]

[0099] In the formula, F h (U) is the objective function of high permeability area, F m (U) is the objective function of the medium penetration region, F l (U) is the objective function of low permeability area, U i is the node voltage, U ref is the reference voltage, Var(U i) is the variance of voltage fluctuation, P1 is the normalized load power, P2 is the normalized PV power, β is the weight factor of fluctuation suppression in the high penetration area, γ is the weight factor of power balance in the medium penetration area, a, a1 and a2 are the high penetration area, medium penetration area and low penetration area respectively;

[0100] Furthermore, the objective functions of different partitions are weighted and summed to obtain the global objective function F(U);

[0101] Furthermore, the gradient descent method is used to optimize F(U) and adjust the node voltages in different regions respectively;

[0102] Furthermore, the impedance of each line in the distribution network is extracted and the connection relationship between nodes and lines in each partition is loaded using GIS data to form a node-line topology table. The admittance Y of each line is calculated based on the line impedance. ij :

[0103]

[0104] In the formula, R ij is the resistance of line ij, X ij is the reactance of line ij, l is the imaginary unit;

[0105] Furthermore, based on the network topology and line admittance, the node admittance matrix Y of partition k is constructed k :

[0106]

[0107] Where Y ii is the self-admittance of node i, which is equal to the sum of the admittances of all lines connected to the node, Y′ ij The calculated node admittance matrix is ​​stored as the network parameter of partition k;

[0108] Furthermore, the optimized node phase angles are extracted from the partitioned raw data matrix and the phase angle differences between nodes are calculated;

[0109] Furthermore, the active power balance equation and reactive power balance equation are constructed based on the node voltage, admittance matrix and phase angle difference:

[0110]

[0111] Where P k,i is the active power output of node i in partition k, V k,i is the voltage amplitude of node i in partition k, obtained through PMU data collection, V k,j is the voltage amplitude of the adjacent node j connected to node i in partition k, G ijis the real part of the admittance matrix between node i and node j, derived from the network topology calculation, and represents the conduction capacity of the line. ij is the imaginary part of the admittance matrix between node i and node j, derived from the network topology calculation, representing the capacitance effect of the line, θ ij is the phase angle difference between node i and node j, Q k,i is the reactive power output of node i in partition k, N k is the total number of nodes that need to be calculated in partition k;

[0112] Furthermore, for each node i in the partition, P is calculated cyclically. k,i and Q k,i , P of all nodes in the partition k,i and Q k,i Integrate into a power distribution matrix;

[0113] Taylor expansion is performed on active power and reactive power, retaining only the first-order terms:

[0114]

[0115] Furthermore, the linearized node active power and reactive power are integrated to form a partitioned linearized power distribution matrix

[0116]

[0117] Furthermore, the partition sensitivity matrix S is constructed based on the linearization results. PQ,k :

[0118]

[0119] Where P k is the active power injected by the nodes in partition k, Q k is the node reactive power injection in partition k, V k is the node voltage amplitude in partition k, δ k is the node voltage phase angle in partition k;

[0120] Furthermore, the target power is set and the deviation ΔP / Q between the actual power and the target power is calculated. k ;

[0121] Calculate the node voltage and phase angle correction Δx using the sensitivity matrix and power imbalance k :

[0122]

[0123] Furthermore, according to the correction value Δx k Iteratively update node voltage and phase angle;

[0124] Furthermore, a threshold value U is set according to the rated voltage range of the power grid until the power imbalance is less than or equal to the threshold value U, and the iteration ends to obtain the final power flow distribution matrix;

[0125] Furthermore, the optimized node voltage and power flow distribution matrix are integrated into the whole network state matrix W.

[0126] It should be noted that real-time data acquisition provides accurate and real-time input for the dynamic analysis of the distribution network. Combined with network modeling, the operating state of the distribution network under different load and photovoltaic power generation conditions can be simulated. The effectiveness of this process directly affects the accuracy and response speed of subsequent fault detection and protection strategies. By calculating the photovoltaic penetration rate and using it as the basis for dividing the area, targeted protection strategies can be set according to the photovoltaic penetration rate of different areas. More flexible protection settings can be adopted in high-penetration areas, while medium and low-penetration areas may only require conventional protection measures. This strategy improves the adaptability and flexibility of the protection system. The voltage optimization objective function helps the power grid optimize the voltage configuration under different operating conditions based on the relationship between voltage fluctuations, load power and photovoltaic power generation. Through iterative optimization by gradient descent method, the optimal voltage distribution can be achieved, especially to solve the problem of voltage instability after photovoltaic access. This process can greatly improve the reliability of the power grid, especially in the operation of high-penetration photovoltaic areas. The use of sensitivity matrix can accurately quantify the impact of power changes between nodes on the entire system and provide an accurate calculation basis for power balance. By performing Taylor expansion on active and reactive power, complex power calculations can be simplified and the efficiency of the power grid optimization process can be improved. By combining the fault detection module with the sensitivity matrix, the fault point can be quickly identified and the fault area can be isolated to ensure that the power supply to the non-fault area is not affected. At the same time, the location of the fault point can be accurately calculated using the wave travel time difference method, which can efficiently and accurately cut off the fault line and improve the fault recovery speed of the system. During the power supply restoration process, important loads are restored first to ensure the power supply to key users. After the power supply is restored, by adjusting the setting value of the protection device in real time, it is possible to avoid false operations or inappropriate protection triggering caused by fluctuations in photovoltaic power generation and ensure the stability of the power grid.

[0127] In an optional embodiment, distribution network fault detection and fault isolation based on network modeling refers to extracting node voltage from the whole network state matrix, traversing node voltage, setting voltage threshold, if the node voltage is greater than the voltage threshold, then the node is judged to be an abnormal node, the abnormal node short-circuit current is calculated according to the source terminal voltage and the abnormal node voltage and impedance, the calculated short-circuit current and the protection setting value of the distribution network are compared, if the short-circuit current is greater than or equal to the protection setting value, then the current node is a short-circuit fault, determine the line number where the fault node is located, and calculate the fault current, and use the wave travel time difference method to calculate the distance between the fault point and the measurement point:

[0128]

[0129] Where d is the distance between the fault point and the measurement point, v is the wave propagation velocity, and t1 and t2 are the times for the wave propagation to reach the two measurement points;

[0130] In an optional embodiment, the objective function is set to minimize the outage load in the non-fault area:

[0131]

[0132] In the formula, I z is the current in the zth circuit, R z is the impedance of the zth line, N represents the number of all considered lines in the network;

[0133] In an optional embodiment, the location of the fault point is obtained based on the distance, and the power flow distribution after each line is cut off is calculated with the fault point as the center, and the minimum number of non-critical lines connected to the fault line is determined to cut off the fault line to ensure that the power outage load is minimized. The main agent sends a cut-off instruction to the disconnector, isolates the fault line according to the determined operation sequence, and verifies the state matrix of the entire network after the isolation is completed and stores the isolation results to ensure that the current of the fault line drops to zero, the power flow and voltage distribution in the non-fault area are as expected, and the isolation does not affect the power supply of other areas.

[0134] It should be noted that by extracting node voltages in real time through the whole network state matrix and analyzing them one by one, nodes with abnormal voltages can be quickly located. This matrix-based analysis method avoids the inefficiency of node-by-node collection and analysis in traditional methods, and provides support for efficient fault detection. By setting the voltage threshold, normal nodes can be quickly filtered out to reduce unnecessary calculation burden. At the same time, the setting of the voltage threshold can flexibly adapt to the operating characteristics of different power grids. The voltage data and line impedance of abnormal nodes are used to quickly calculate the short-circuit current, providing a basis for judging whether a short-circuit fault occurs at the node. The location of the fault point can be accurately located by the wave travel time difference method, especially in long-distance lines with high positioning accuracy. The isolation strategy is optimized through the objective function to avoid cutting off key lines and minimize the power outage load in non-fault areas. The isolation operation is centrally managed by the agent system, which can realize fast command issuance and execution, while avoiding delays and errors in human operations. After the isolation is completed, the whole network state matrix is ​​verified to ensure that the isolation does not affect the power flow and voltage distribution in the non-fault area. The verification results are stored in the database to provide data support for subsequent analysis and optimization.

[0135] S103, restoring power supply to several areas after fault isolation is completed, and adjusting setting values ​​of protection devices in real time according to operating data of several areas.

[0136] In the embodiment of the present application, the power supply of the plurality of areas after the fault isolation is completed is restored includes:

[0137] Obtaining load importance in a plurality of areas, and performing a first priority sorting on the loads in the plurality of areas according to the load importance;

[0138] Power supply to corresponding areas is restored in order according to the first priority ranking.

[0139] In an optional embodiment, the load importance is determined based on the operating requirements of key facilities and equipment in the area. For example, the loads of key facilities such as hospitals, fire stations, and data centers will be given higher priority because they have higher requirements for the continuity and stability of power supply. In addition, the importance of the load may also take into account factors such as population density and economic activity intensity to ensure that during the power restoration process, areas with greater social and economic impacts can get priority in power supply.

[0140] In an optional embodiment, after the power supply of the corresponding areas is restored in order according to the first priority, the system will monitor the voltage and current data of these areas to ensure that the power supply quality meets the standards. If any abnormality is detected during the restoration process, the system will immediately take measures, such as adjusting the power supply strategy or starting the backup power supply, to prevent the spread of the fault and the expansion of its impact.

[0141] In the embodiment of the present application, the real-time adjustment of the setting value of the protection device according to the operating data of several areas includes:

[0142] Calculating a first set of setting values ​​for each protection line in the area one by one according to a number of area operation data;

[0143] The first set of setting values ​​is sent to the corresponding protection device, and the setting values ​​of the protection device are adjusted in real time.

[0144] In an embodiment of the present application, restoring power supply to non-fault areas after isolation is completed means prioritizing all loads in non-fault areas according to the load importance of the distribution network, and the master agent closes the circuit breakers in the corresponding areas in sequence according to the load priority to restore power supply to the non-fault areas.

[0145] It should be noted that priority should be given to restoring loads that have a significant impact on society and the economy, such as hospitals, communication base stations, and traffic lights. Through scientific sequencing, the negative impact of power outages on residents' lives and industrial production can be minimized as much as possible. Circuit breakers are closed gradually to avoid instantaneous overload problems caused by large-scale loads being connected to the grid at the same time. The main agent flexibly adjusts the circuit breaker closing sequence based on monitoring to ensure that power supply is restored quickly and safely. The real-time adjustment mechanism adapts to the complex load demand and instability of photovoltaic power generation in non-fault areas, discovers potential problems in a timely manner through operating status monitoring, avoids secondary power outages, analyzes historical recovery data, improves circuit breaker closing algorithms and load importance ranking methods, and provides detailed recovery process data for the grid dispatching center and relevant departments for further optimization of grid management.

[0146] Furthermore, real-time adjustment of the setting value of the protection device means that after the power supply is restored, the operation data of each area after power supply is collected in real time, and the setting value of the protection device is dynamically adjusted according to the operation data after pre-processing the data:

[0147] I=I1×(1+J)

[0148] Where I1 is the basic setting current value, and J is the setting margin, which is obtained by subtracting the minimum value from the maximum value of the short-circuit current and dividing it by the maximum value of the short-circuit current;

[0149] The setting value (i.e., the first setting value set) is calculated for each protection line one by one, and after updating, the new setting value (the first setting value set) is sent to the corresponding protection device.

[0150] It should be noted that real-time adjustment of the setting value of the protection device can dynamically optimize the sensitivity of the protection device according to the actual operating status of the power grid, so that it can better adapt to the current fluctuations that may occur after photovoltaic access. After the power supply is restored, the system pre-processes the real-time operating data of each area and dynamically adjusts the setting value of the protection device, thereby avoiding the malfunction or delayed reaction of the traditional protection system under the fluctuation of photovoltaic power generation. Real-time adjustment of the setting value enhances the adaptability of the distribution network to load fluctuations and short-circuit faults. The sensitivity of the protection device can be dynamically optimized as the power grid status changes, and the setting value is calculated for each line one by one to achieve differentiated protection configuration and ensure priority protection of key lines. Through this technology, the power grid can respond to various loads and power grid changes more accurately, and improve the efficiency of fault diagnosis and isolation. The setting value of the protection device can be quickly updated to ensure that the latest calculation results can take effect immediately.

[0151] In summary, the present invention proposes a method for configuring distribution network system protection in a whole-county photovoltaic power supply scenario, obtaining first photovoltaic access information within a target range, and performing first preprocessing on the first photovoltaic access information; establishing a first network based on the first preprocessing result, and the first network is used for fault detection and fault isolation; restoring power supply to several areas after fault isolation is completed, and adjusting the setting value of the protection device in real time based on the operating data of several areas. Differentiated protection configurations are implemented for areas with different penetration rates, distribution network faults can be accurately detected, and the faulty area can be quickly isolated to avoid affecting the normal power supply of non-faulty areas. The setting value of the protection device can be adjusted in real time according to the flow optimization algorithm, and the performance of the distribution network protection device can be optimized to make it more adaptable to the fluctuation of the power grid after the photovoltaic power supply is connected, ensuring efficient operation in a complex photovoltaic power generation environment, and being able to respond to changes in the power grid status in a timely manner, avoiding delays and false operations in traditional protection strategies.

[0152] Example 2

[0153] In a preferred embodiment, the distribution network system protection configuration results can also be displayed and stored in a database;

[0154] Specifically, displaying the distribution network system protection configuration result means obtaining the distribution network system protection configuration result and then obtaining the whole network state matrix, and displaying the distribution network system protection configuration result and the whole network state matrix in correspondence.

[0155] Displaying the distribution network system protection configuration results in correspondence with the whole network status matrix can greatly improve the response accuracy of the distribution network protection system. When a power grid fault occurs, the system can dynamically adjust the setting value of the protection device according to the power grid status matrix in real time, and quickly display the fault location, protection strategy and recovery measures through visualization means to ensure that the distribution network can restore normal power supply in the shortest time. After displaying the distribution network system protection configuration in correspondence with the whole network status matrix, the distribution network operator can accurately adjust the configuration of the protection device according to the real-time operation status of the power grid. Through this display method, the working status and settings of each protection device can be clearly understood, and potential problems can be discovered in time. For example, in areas with high photovoltaic penetration rates, photovoltaic power generation fluctuates greatly. The system can automatically adjust the protection configuration according to voltage fluctuations and power changes, thereby avoiding false operation or leakage protection and improving the reliability of the system.

[0156] Furthermore, storing in a database means storing the distribution network data and the corresponding setting values ​​of the distribution network system protection device in the database, and classifying and storing them according to partitions. The database synchronizes the stored data to the cloud for backup.

[0157] Through unified storage and classification management, the management difficulty of distribution network operation data is simplified, making the query and call of massive data more efficient. The set value is updated in real time as the grid operation status changes, and is stored in the database to facilitate subsequent algorithm model calls, providing basic support for dynamic protection configuration. Partitioned storage realizes regional management of data, making it easy to formulate personalized protection strategies for areas with different penetration rates.

[0158] Example 3

[0159] This embodiment also provides a distribution network system protection configuration system in a whole-county photovoltaic power supply scenario, including:

[0160] A data acquisition and processing module, used for acquiring first photovoltaic access information within a target range, and performing first preprocessing on the first photovoltaic access information;

[0161] A network establishing module, used to establish a first network according to the first preprocessing result, wherein the first network is used for fault detection and fault isolation;

[0162] The setting module is used to restore power supply to several areas after fault isolation is completed, and to adjust the setting values ​​of protection devices in real time according to the operating data of several areas.

[0163] The above-mentioned unit modules may be embedded in or independent of a processor in a computer device in the form of hardware, or may be stored in a memory in a computer device in the form of software, so that the processor can call and execute operations corresponding to the above-mentioned modules.

[0164] This embodiment also provides a computer device, which may be a terminal, and its internal structure diagram may be as shown in FIG. Figure 2 As shown. The computer device includes a processor, a memory, a communication interface, a display screen and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be achieved through WIFI, an operator network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, a distribution network system protection configuration method for the entire county photovoltaic power supply scenario is implemented. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covered on the display screen, or a button, trackball or touchpad set on the housing of the computer device, or an external keyboard, touchpad or mouse.

[0165] This embodiment further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the following steps are implemented:

[0166] Acquire first photovoltaic access information within a target range, and perform first preprocessing on the first photovoltaic access information;

[0167] Establishing a first network according to the first preprocessing result, wherein the first network is used for fault detection and fault isolation;

[0168] Restore power supply to several areas after fault isolation is completed, and adjust the setting values ​​of protection devices in real time based on the operating data of several areas.

[0169] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

[0170] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of complete hardware embodiments, complete software embodiments, or embodiments in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code. The scheme in the embodiments of the present application can be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0171] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0172] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0173] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0174] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0175] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A distribution network system protection configuration method in a whole-county photovoltaic power supply scenario, characterized in that: include: Acquire first photovoltaic access information within a target range, and perform first preprocessing on the first photovoltaic access information; Establishing a first network according to the first preprocessing result, wherein the first network is used for fault detection and fault isolation; Restore power supply to several areas after fault isolation is completed, and adjust the setting values ​​of protection devices in real time based on the operating data of several areas.

2. The method for configuring distribution network protection in a whole-county photovoltaic power supply scenario according to claim 1, characterized in that: The first preprocessing at least includes: Acquire a first penetration rate according to the first photovoltaic access information; Regional division is performed according to the first permeability combined with a first regional division criterion.

3. The method for configuring distribution network protection in a whole-county photovoltaic power supply scenario as claimed in claim 2, characterized in that: The establishing of the first network according to the first preprocessing result comprises: Obtaining first target parameters and second target parameters of target key points in a plurality of regions after region division; Establishing a network status matrix for a plurality of areas according to the first target parameter and the second target parameter; A first integration is performed on the network status matrices of the plurality of regions to obtain a first network.

4. The method for configuring distribution network protection in a whole-county photovoltaic power supply scenario as claimed in claim 3, characterized in that: The power supply of the plurality of areas after the fault isolation is completed includes: Obtaining load importance in a plurality of areas, and performing a first priority sorting on the loads in the plurality of areas according to the load importance; Power supply to corresponding areas is restored in order according to the first priority ranking.

5. The method for configuring distribution network protection in a whole-county photovoltaic power supply scenario as claimed in claim 4, characterized in that: The real-time adjustment of the setting value of the protection device according to the operating data of several areas includes: Calculating a first set of setting values ​​for each protection line in the area one by one according to a number of area operation data; The first set of setting values ​​is sent to the corresponding protection device, and the setting values ​​of the protection device are adjusted in real time.

6. The method for configuring distribution network protection in a whole-county photovoltaic power supply scenario as claimed in claim 5, characterized in that: The acquiring the first penetration rate according to the first photovoltaic access information includes: Acquire the first photovoltaic access information of the photovoltaic access point within the target range; Acquire the preliminary power generation capacity and regional total load capacity of the photovoltaic access points within the target range according to the first photovoltaic access information; The first penetration rate is calculated according to the preliminary power generation capacity of the photovoltaic access points within the target range and the total load capacity of the region.

7. The method for configuring distribution network protection in a whole-county photovoltaic power supply scenario as claimed in claim 6, characterized in that: The first area division criteria include: Setting a first partition threshold and a second partition threshold; Establishing a first area division criterion based on the first division threshold and the second division threshold; Regional division is performed according to the first permeability combined with a first regional division criterion.

8. A distribution network system protection configuration system in a whole-county photovoltaic power supply scenario, characterized in that: include: A data acquisition and processing module, used for acquiring first photovoltaic access information within a target range, and performing first preprocessing on the first photovoltaic access information; A network establishing module, used to establish a first network according to the first preprocessing result, wherein the first network is used for fault detection and fault isolation; The setting module is used to restore power supply to several areas after fault isolation is completed, and to adjust the setting values ​​of protection devices in real time according to the operating data of several areas.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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