Partition power grid toughness planning method based on important load differentiation guarantee supply principle

Abstract

The invention provides a partition power grid toughness planning method based on an important load differentiation guarantee supply principle. The method comprises the steps of setting an important load differential supply guarantee principle and a multi-level power supply guarantee principle in a partitioned power grid, analyzing an existing component upgrading demand in the partitioned power grid, determining a newly added component position, and constructing a planning model based on the important load differential supply guarantee principle, the multi-level power supply guarantee principle and the newly added component position, and solving the planning model to obtain a toughness planning strategy. According to the embodiment of the invention, the urban power grid toughness planning method is put forward from the perspective of improving the important load capability of the urban power grid under extreme events by ensuring basic operation of the city and reducing social influence as far as possible.

Description

Technical Field

[0001] The present invention relates to the technical field of power grid boundary demarcation, and in particular to a regional power grid resilience planning method based on the principle of differentiated supply guarantee of important loads. Background Art

[0002] The load density in cities is high, and there are many important loads such as key infrastructure. Once a power outage occurs, a series of chain reactions will occur, causing huge losses. In addition, due to factors such as space limitations, there are relatively few power sources in cities, and the proportion of external power supply is high. Once the external power supply channel is destroyed, the risk of power outage in the city is high. Therefore, it is urgent to improve the resilience of urban power grids. By upgrading or adding new transmission lines, substations and generators, the resilience planning measures can enhance the defense and recovery capabilities of urban power grids in the face of extreme events, provide continuous power supply to important loads, and reduce losses.

[0003] At present, the grid resilience planning methods in the existing technology are mainly carried out for large power grids or medium and low voltage distribution networks. The relevant methods mainly include heuristic methods, stochastic optimization and robust optimization. The uncertainty faced in the planning problem mainly comes from the uncertainty of the frequency and intensity of extreme events during the planning period and the uncertainty of the damage caused by extreme events to the power system. The general idea of ​​the heuristic method is to evaluate the candidate planning schemes based on the proposed resilience assessment model, so as to select the planning scheme. Among them, the main process of resilience assessment includes constructing a spatiotemporal evolution model of the main characteristics of a certain disaster (such as wind speed, peak acceleration of seismic motion, etc.), a vulnerability probability model of power components under this disaster, obtaining the failure state of system components, and then obtaining the performance of the system through power flow calculation, such as load shedding or key load power failure as resilience assessment indicators. The stochastic optimization method mainly generates representative extreme scenarios by assuming the probability distribution of random parameters, and makes decisions by optimizing the performance indicators of the system under representative scenarios. The main idea of ​​the robust optimization method is to minimize the system cost in the worst case, and its consideration of uncertainty lies in constructing an uncertainty set of random variables. At present, the consideration of extreme events is mainly based on the generation of extreme accidental event sets or historical extreme scenarios; the consideration of the impact of extreme events on the power grid mainly assumes that the number of system fault components in the worst case is not less than n, and is considered based on the Cardinality uncertainty set.

[0004] The shortcomings of the grid resilience planning methods in the above-mentioned prior art include: the above methods all make assumptions and deal with the uncertainty of extreme events and the uncertainty of damage to the system. However, both types of uncertainties belong to extreme uncertainties, and their characteristics cannot be objectively and accurately characterized using probability model methods. For example, it is difficult to represent the possible future degradation state of the system using limited extreme representative scenarios, and the failure probability calculated by the fragility curve may have large errors because these curves are formulated under assumptions that may not be applicable to actual conditions. Inaccurate probability models will affect the effectiveness of investment decisions. Due to the unknown nature of extreme events, limited extreme scenarios are difficult to represent extreme scenarios that may occur in the future, and the probability of occurrence of each scenario is also subjective. Summary of the invention

[0005] An embodiment of the present invention provides a method for planning resilience of a regional power grid based on the principle of differentiated supply guarantee of important loads, so as to effectively optimize resource allocation of the regional power grid.

[0006] In order to achieve the above object, the present invention adopts the following technical scheme.

[0007] According to one aspect of the present invention, a method for planning resilience of a regional power grid based on the principle of differentiated supply guarantee of important loads is provided, comprising:

[0008] Set up the principle of differentiated supply guarantee for important loads in the zoned power grid and the principle of multi-level power supply guarantee;

[0009] Analyze the upgrade requirements of existing components in the sub-grid and determine the location of new components;

[0010] A planning model is constructed based on the principle of differentiated supply of important loads, the principle of multi-level power supply guarantee and the location of new components, and the planning model is solved to obtain a resilience planning strategy.

[0011] Preferably, the principle of setting differentiated supply guarantee for important loads in the zoned power grid and the principle of multi-level power supply guarantee include:

[0012] The principle of differentiated supply guarantee for important loads in the zoned power grid includes: the guaranteed power supply for super-important loads is located at the level where the load is located; the guaranteed power supply for first-level important loads is located at the level where the load is located and the level above; the guaranteed power supply for second-level important loads is located at the level above the level where the load is located;

[0013] The principles for setting up multi-level power supply guarantees in zoned power grids include: important loads cannot be guaranteed by lower-level power supplies, that is, the loads cannot be guaranteed through lines at the next voltage level, and the power supply cannot be guaranteed through lines at the previous voltage level.

[0014] Preferably, the constraints corresponding to the principle of differentiated supply guarantee for important loads and the principle of multi-level power supply guarantee are as follows:

[0015]

[0016] In the formula, represents the number of guaranteed power sources for load l at level c, is a binary variable, indicating whether the load l is protected by the power source s. They represent the super important load set, the first important load set, and the second important load set respectively; c is the level index;

[0017] This constraint indicates the number of guaranteed power sources for load l at level c. It is equal to the sum of the protection conditions of all power sources for the load at this level, and according to the principle of power supply planning for important loads of different levels, it ensures that any important load can obtain at least one guaranteed power source.

[0018] Preferably, the analyzing the upgrade requirements of existing components in the sub-area power grid and determining the locations of new components includes:

[0019] Analyze the existing grid structure, substation conditions and power supply security, analyze the existing component upgrade needs based on the types of extreme disasters that may occur in the corresponding areas, determine the line, substation, power supply upgrade plan and budget, refer to historical experience data based on heuristic methods combined with geographical constraints of line planning and network connectivity indicators, identify weak links, and determine the location of new components, which includes new line corridors, substation locations and power supply locations.

[0020] Preferably, the planning model is constructed based on the principle of differentiated supply guarantee of important loads, the principle of multi-level power supply guarantee and the location of newly added components, and the planning model is solved to obtain a resilience planning strategy, including:

[0021] The objective function of the planning model is set based on the differentiated supply guarantee principle of important loads and the multi-level power supply guarantee principle, and the multi-level guarantee constraints, planning variable logic and budget constraints of important loads are set;

[0022] Based on the multi-level protection constraints of the important loads, the planning variable logic and the budget constraints, a solver is used to solve the objective function of the planning model to obtain a resilience planning strategy, which includes the capacity, location and type of new power sources at each voltage level, status information of line upgrades / reinforcement, and the protection relationship between each power source and the important loads.

[0023] Preferably, the objective function of the planning model is:

[0024] max RpL Lp C C (3)

[0025]

[0026]

[0027] Among them, R represents the weighted sum of the number of guaranteed power sources, that is, the number of power sources guaranteed for the load, p L 、p C is the weight coefficient, which indicates the importance of the final planning scheme to the power supply path and budget cost; L indicates the total length of the power supply path; C indicates the total budget cost required for planning; represents the length of the power supply path for load l guaranteed by power source s; w l Indicates the importance level of the load node; Indicates the new construction cost of lines, guaranteed power sources and substations; Indicates the upgrade costs of lines, guaranteed power supplies, and substations; They are all binary variables, indicating whether the resource is newly added; They are all binary variables, indicating whether the resource is upgraded;

[0028] The multi-level protection constraints of the important loads are as follows:

[0029]

[0030] Among them, l is the load index, s is the power index, and i / j / k is the node index; represents the active power flowing through the line supplied by the power source s to the load l; p l represents the active power of load l; Indicates the active power supplied by power source s to load l; a ij is a binary variable, indicating whether line (i, j) is in an upgraded state, that is, whether line (i, j) has been upgraded / built; c l 、c s 、c ij Indicates the voltage level to which the component belongs; s is a binary variable, indicating whether the power supply s is added / upgraded; L i，j Indicates the length of the line; is a binary variable, indicating whether line (i, j) is energized when load l is powered by power source s; i，j Indicates that if line (i, j) is in the upgraded state, the weight of the line length is 1, otherwise it is 0;

[0031] The planning variable logic and budget constraints are as follows:

[0032]

[0033] Among them, ε C , S C , Respectively represent the new line, power source, and substation set to be built; ε0, S0, They represent the sets of lines, power sources and substations that do not need to be newly built; ε up , S up , Respectively represent the upgraded lines, power sources, and substations; β b It is a binary variable, indicating whether substation b is upgraded.

[0034] According to another aspect of the present invention, a zoned power grid resilience planning device based on the principle of differentiated supply guarantee of important loads is provided, comprising:

[0035] The supply guarantee principle and security principle setting module is used to set the differentiated supply guarantee principle and multi-level power supply security principle for important loads in the zoned power grid;

[0036] A new component location determination module is used to analyze the upgrade requirements of existing components in the zoned power grid and determine the location of new components;

[0037] The resilience planning strategy determination module is used to build a planning model based on the differentiated supply guarantee principle of important loads, the multi-level power supply guarantee principle and the location of new components, solve the planning model, and obtain a resilience planning strategy.

[0038] Preferably, the supply guarantee principle and guarantee principle setting module are used to set the differentiated supply guarantee principle of important loads in the zoned power grid, including: the guaranteed power supply of the super important load is located at the level where the load is located; the guaranteed power supply of the first important load is located at the level where the load is located and the previous level; the guaranteed power supply of the second important load is located at the level above the level where the load is located;

[0039] The principles for setting up multi-level power supply guarantees in zoned power grids include: important loads cannot be guaranteed by lower-level power supplies, that is, the loads cannot be guaranteed through lines at the next voltage level, and the power supply cannot be guaranteed through lines at the previous voltage level.

[0040] Preferably, the module for determining the location of new components is used to analyze the existing grid structure, substation conditions and power supply conditions, analyze the upgrade needs of existing components based on the types of extreme disasters that may occur in the corresponding areas, determine the line, substation, power supply upgrade plan and budget, refer to historical experience data based on heuristic methods combined with geographical constraints of line planning and network connectivity indicators, identify weak links, and determine the location of new components, which includes new line corridors, substation locations and power supply locations.

[0041] Preferably, the resilience planning strategy determination module is used to set the objective function of the planning model based on the differentiated supply guarantee principle of important loads and the multi-level power supply guarantee principle, and to set the multi-level guarantee constraints, planning variable logic and budget constraints of important loads;

[0042] Based on the multi-level protection constraints of the important loads, the planning variable logic and the budget constraints, a solver is used to solve the objective function of the planning model to obtain a resilience planning strategy, which includes the capacity, location and type of new power sources at each voltage level, status information of line upgrades / reinforcement, and the protection relationship between each power source and the important loads.

[0043] It can be seen from the technical solutions provided by the above-mentioned embodiments of the present invention that the embodiments of the present invention take ensuring the basic operation of the city and minimizing the social impact as the starting point, and propose a method for urban power grid resilience planning from the perspective of improving the ability of the urban power grid to ensure important loads under extreme events.

[0044] Additional aspects and advantages of the present invention will be given in part in the following description, which will become obvious from the following description, or may be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0046] Figure 1 A schematic diagram of multi-level protection and island operation provided by an embodiment of the present invention.

[0047] Figure 2 A flow chart of a method for planning the resilience of a multi-level strong local partitioned power grid based on the principle of differentiated supply of important loads provided by the present invention.

[0048] Figure 3 The present invention provides a topological diagram of a regional power grid in a domestic city.

[0049] Figure 4 A schematic diagram of a multi-level strong local power grid planning strategy provided by the present invention;

[0050] Figure 5 A structural diagram of a zoned power grid resilience planning device based on the principle of differentiated supply guarantee for important loads provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0051] The embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be interpreted as limiting the present invention.

[0052] It will be understood by those skilled in the art that, unless expressly stated, the singular forms "one", "said", and "the" used herein may also include plural forms. It should be further understood that the term "comprising" used in the specification of the present invention refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof. It should be understood that when we refer to an element as being "connected" or "coupled" to another element, it may be directly connected or coupled to the other element, or there may be intermediate elements. In addition, the "connection" or "coupling" used herein may include wireless connection or coupling. The term "and / or" used herein includes any unit and all combinations of one or more associated listed items.

[0053] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those generally understood by those skilled in the art in the art to which the present invention belongs. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with the meanings in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless defined as herein.

[0054] To facilitate understanding of the embodiments of the present invention, several specific embodiments will be further explained below with reference to the accompanying drawings, and each embodiment does not constitute a limitation on the embodiments of the present invention.

[0055] Urban power grids are generally load centers with high load density. In order to limit system short-circuit current and other reasons, urban power grids are generally operated in sections. Sections refer to a network structure that uses one or more 500kV substations as the center to drive the 220kV regional load to operate in sections, that is, the 220kV power grids in different sections are operated in a decoupled manner. Sectioned power grids are generally receiving-end power grids that receive power from 500kV power grids and transmit power through the main 220kV transmission channels. They have the following characteristics:

[0056] 1. The area forms a structure with 220kV ring network as the main grid, and there are generator sets of certain capacity in the sub-areas, and the intervals have certain mutual supply capabilities;

[0057] 2. Due to the high load density, the area usually contains multiple voltage levels, and power generation resources are connected to different voltage levels. Generally speaking, the higher the voltage level, the larger the power scale, and the higher the reliability of the line and power supply;

[0058] 3. A large number of interconnection lines are built between the substations of the same level in the high-voltage distribution network. Each substation is connected to the power supply point of the 220kV transmission network through multiple power supply paths, and the grid topology is flexible.

[0059] Example 1

[0060] Figure 1 A schematic diagram of multi-level protection and island operation provided for an embodiment of the present invention. Considering the huge impact of extreme events, the present invention cuts in from the perspective of important load supply guarantee and proposes an urban power grid resilience planning method for the extreme survival of important loads. There are two key aspects to the supply guarantee of important loads in extreme situations: power generation resources and corresponding power transmission corridors. By selectively upgrading or adding strong lines, substations and power sources, the "lifeline" of important loads is constructed to ensure resistance to invasion under extreme events, and the source grid load forms an electrical island to achieve uninterrupted power supply or rapid recovery of important loads, thereby achieving extreme survival. In addition, considering that the low-voltage level power grid is closer to the important load, the load power supply can be guaranteed faster under extreme events; and the high-voltage level facilities have stronger ability to resist extreme events and are more reliable under extreme events. Therefore, a multi-level protection scheme for important loads is proposed, and each level of local power grid has the ability to operate independently, and the multi-voltage level guarantees are redundant with each other. When an extreme event causes a serious failure, it switches to the island operation mode at a certain level according to the actual situation.

[0061] The flowchart of a method for implementing a multi-level strong local partition power grid boundary division and resource allocation optimization method based on the principle of differentiated supply guarantee of important loads provided by an embodiment of the present invention is as follows: Figure 2 As shown, the following processing steps are included:

[0062] Step S1: Determine the principle of differentiated supply of important loads and the principle of multi-level power supply guarantee.

[0063] Step S2: Analyze the upgrade requirements of existing components and determine the location of new components. The new components include a collection of lines, power supplies and substations to be built. Clarify the existing grid structure (multiple voltage levels, interconnection lines, cables / overhead lines and corresponding disaster resistance levels), substation conditions (indoor / outdoor, design standards and disaster resistance), and guaranteed power supply conditions (type, capacity, whether it has black start capability or island operation capability, etc.). Based on the types of extreme disasters that may occur in the corresponding areas, determine the upgrade plan and budget for lines, substations, and power supplies. For areas that are often affected by wind disasters or ice storms, upgrade measures may include undergrounding overhead lines. Considering factors such as urban space constraints, determine the location of new line corridors, substations, and power sources. New components are upgraded with resilience enhancement measures.

[0064] The strong local power grid is aimed at extreme power system failures caused by serious natural disasters that exceed the defense standards. It takes ensuring the basic operation of the city and minimizing the social impact as the starting point, and takes special-grade, part-grade and second-grade important loads as the protection objects. The city's relevant substations, lines and local security power supplies are selected for differentiated construction and maintenance to ensure that important loads and security loads are not shut down, and non-security loads are quickly restored to power. The minimum-scale grid also has the ability to operate on an isolated island.

[0065] Considering that low-voltage power grids are closer to important loads, they can ensure power supply to loads more quickly in extreme events; and high-voltage facilities have stronger resistance to extreme events and are more reliable in extreme events. Therefore, a multi-level strong local power grid is introduced, and each level of local power grid has the ability to operate independently. Multiple voltage levels are mutually redundant. When an extreme event causes a serious failure, it switches to the island operation mode at a certain level according to the actual situation.

[0066] With reference to historical experience data, based on heuristic methods, combined with geographical constraints of line planning and indicators such as network connectivity, weak links are identified to determine the location of new components.

[0067] Step S3: Formulate a resilience planning scheme. Based on the above, consider planning principles, budget constraints, etc., and formulate a resilience planning scheme with the goal of maximizing the survivability of important load limits.

[0068] Specifically, the above step S1 includes:

[0069] 1: Principle of differentiated supply guarantee for important loads: The power supply for super-important loads is located at the level where the load is located; the power supply for first-level important loads can be located at the level where the load is located and the level above; the power supply for second-level important loads can be located at the level above the level where the load is located.

[0070] 2: Multi-level power supply guarantee principle: important loads cannot be guaranteed by the lower-level power supply, that is, the load cannot be guaranteed by the line of the next voltage level, and the power supply cannot be guaranteed by the line of the previous voltage level.

[0071] The constraints corresponding to the principle of differentiated supply guarantee for important loads and the principle of multi-level power supply guarantee are as follows:

[0072]

[0073]

[0074] In the formula, It represents the number of guaranteed power sources for load l at level c; is a binary variable, indicating whether the load l is guaranteed by the power source s; They represent the super important load set, the first important load set, and the second important load set respectively; c is the hierarchical index.

[0075] This constraint indicates the number of guaranteed power sources for load l at level c. It is equal to the sum of the protection of all power sources for the load at this level. And according to the principle of power supply planning for important loads of different levels, it is ensured that any important load can obtain at least one guaranteed power source.

[0076] Specifically, the above step S2 includes: Figure 3 A topological diagram of a subdistrict power grid in a certain city in China provided by the present invention. The subdistrict power grid includes voltage levels such as 220kV, 110kV, 35kV and 10kV, with a total of 4 levels. There is a power plant connected to 220kV in the original subdistrict, which is a black start unit and does not need to be upgraded; 6 220kV substations, 15 110kV substations, and for the convenience of analysis, only 35kV and 10kV substations containing important loads are displayed, with 5 and 22 respectively. The system contains 1 special load, 3 first-level loads, and 4 second-level loads, which are connected to different substations. It can be seen that the communication between the various levels within the urban subdistrict power grid is rich and the reliability is high. It is worth noting that during normal operation, each substation is only electrically connected to one upper-level substation. For example, for 110kV substation 7, under normal operation, only one line 1-7 or 2-7 is closed. Assuming that all lines and substations can be upgraded, and considering the urban space limitations, there are 7 locations for power supply access.

[0077] Specifically, the above step S3 includes: the extreme survivability of important loads depends on the power supply and power transmission channel that can supply power to them in extreme scenarios, that is, the number of power supplies that guarantee their power supply. Therefore, the main goal is to maximize the number of guaranteed power supplies for the load, considering the importance of the load as a weight. In addition, the closer the electrical distance between the guaranteed power supply and the load, the higher the power supply reliability in extreme events. Therefore, the power supply distance is taken as a secondary goal. At the same time, minimizing the budget is also considered as a secondary goal.

[0078] The objective function of the planning model is:

[0079] max Rp L Lp C C (3)

[0080]

[0081]

[0082] Where R represents the weighted sum of the number of guaranteed power sources, that is, the number of power sources guaranteed for the load; p L 、p C is the weight coefficient, which indicates the importance of the final planning scheme to the power supply path and budget cost; L indicates the total length of the power supply path; C indicates the total budget cost required for planning; represents the length of the power supply path for load l guaranteed by power source s; w l Indicates the importance level of the load node; Indicates the new construction cost of lines, guaranteed power sources and substations; Indicates the upgrade costs of lines, guaranteed power supplies, and substations; They are all binary variables, indicating whether the resource is newly added; Both are binary variables, indicating whether the resource is upgraded.

[0083] The multi-level protection constraints of important loads are as follows:

[0084]

[0085] Among them, 1 is the load index, s is the power index, and i / j / k is the node index; represents the active power flowing through the line supplied by the power source s to the load l; p l represents the active power of load l; Indicates the active power supplied by power source s to load l; a ij is a binary variable, indicating whether line (i, j) is in an upgraded state, that is, whether line (i, j) has been upgraded / built; c l 、c s 、c ijIndicates the voltage level to which the component belongs; s is a binary variable, indicating whether the power supply s is added / upgraded; L i，j Indicates the length of the line; is a binary variable, indicating whether line (i, j) is energized when load l is powered by power source s; i，j It means that if the line (i, j) is in the upgraded state, the weight of the line length is 1, otherwise it is 0.

[0086] The planning variable logic and budget constraints are as follows:

[0087]

[0088] C≤C max (twenty two)

[0089] Among them, ε C , δ C , Respectively represent the new line, power source, and substation set to be built; ε0, δ0, They represent the sets of lines, power sources and substations that do not need to be newly built; ε up , δ up , Respectively represent the upgraded lines, power sources, and substations; β b is a binary variable, indicating whether substation b is upgraded. After the location of the new component is determined, the corresponding parameters can be determined.

[0090] The above planning model is solved by the mature solver Gurobi. The resilience planning strategy obtained includes the capacity, location and type of new power sources at each voltage level, the status information of line upgrade / reinforcement, and the protection relationship between each power source and important loads. The proposed method is used to solve the example and obtain the planning strategy as follows: Figure 4 As shown, three 10kV local grids, one 35kV local grid, one 110kV and one 220kV local grid are formed. The R in the objective function is 2910, and the total budget is 840.24 million yuan.

[0091] from Figure 4It can be seen that the primary load at 7 is connected to 110kV, and is protected by the 110kV power supply at 39 and the 220kV power supply at 38, and is protected by the local and upper-level local power grids, meeting the planning principles. The 10kV secondary load at 27 is protected by the most 4-level local power grids. The reason is that it is close to other important loads, such as 28 and 20, in electrical distance. Under the current planning rules, 28 and 20 both need at least this level of protection, and the three loads share part of the "lifeline". In contrast, the tertiary important load at bus 46, due to its long electrical distance from other important loads, meets the protection needs of this level under a limited budget and forms a strong local power grid.

[0092] The urban power grid planning principle based on multi-layer protection of important loads in the present invention can be determined by actual operating conditions, and the calculation examples tested in the invention can be replaced by other multi-layer urban power grid calculation examples.

[0093] Example 2

[0094] The structure of a partitioned power grid resilience planning device based on the principle of differentiated supply guarantee of important loads provided in this embodiment is as follows: Figure 5 As shown, it includes the following modules:

[0095] The supply guarantee principle and security principle setting module is used to set the differentiated supply guarantee principle and multi-level power supply security principle for important loads in the zoned power grid;

[0096] A new component location determination module is used to analyze the upgrade requirements of existing components in the zoned power grid and determine the location of new components;

[0097] The resilience planning strategy determination module is used to build a planning model based on the differentiated supply guarantee principle of important loads, the multi-level power supply guarantee principle and the location of new components, solve the planning model, and obtain a resilience planning strategy.

[0098] The above-mentioned supply guarantee principle and guarantee principle setting module are specifically used to set the differentiated supply guarantee principle of important loads in the zoned power grid, including: the guaranteed power supply of the super-important load is located at the level where the load is located; the guaranteed power supply of the first-level important load is located at the level where the load is located and the level above; the guaranteed power supply of the second-level important load is located at the level above the level where the load is located;

[0099] The principles for setting up multi-level power supply guarantees in zoned power grids include: important loads cannot be guaranteed by lower-level power supplies, that is, the loads cannot be guaranteed through lines at the next voltage level, and the power supply cannot be guaranteed through lines at the previous voltage level.

[0100] The constraints corresponding to the principle of differentiated supply guarantee for important loads and the principle of multi-level power supply guarantee are as follows:

[0101]

[0102] In the formula, represents the number of guaranteed power sources for load l at level c, is a binary variable, indicating whether the load l is protected by the power source s. They represent the super important load set, the first important load set, and the second important load set respectively; c is the level index;

[0103] This constraint indicates the number of guaranteed power sources for load l at level c. It is equal to the sum of the protection conditions of all power sources for the load at this level, and according to the principle of power supply planning for important loads of different levels, it ensures that any important load can obtain at least one guaranteed power source.

[0104] The above-mentioned module for determining the location of new components is specifically used to analyze the existing grid structure, substation conditions and power supply conditions, analyze the upgrade needs of existing components based on the types of extreme disasters that may occur in the corresponding areas, determine the line, substation, power supply upgrade plan and budget, refer to historical experience data based on heuristic methods combined with geographical constraints of line planning and network connectivity indicators, identify weak links, and determine the location of new components. The location of new components includes new line corridors, substation locations and power supply locations.

[0105] The above-mentioned resilience planning strategy determination module is specifically used to set the objective function of the planning model based on the differentiated supply guarantee principle of important loads and the multi-level power supply guarantee principle, and set the multi-level guarantee constraints, planning variable logic and budget constraints of important loads;

[0106] Based on the multi-level protection constraints of the important loads, the planning variable logic and the budget constraints, a solver is used to solve the objective function of the planning model to obtain a resilience planning strategy, which includes the capacity, location and type of new power sources at each voltage level, status information of line upgrades / reinforcement, and the protection relationship between each power source and the important loads.

[0107] The objective function of the planning model is:

[0108] max Rp L Lp C C (3)

[0109]

[0110]

[0111] Among them, R represents the weighted sum of the number of guaranteed power sources, that is, the number of power sources guaranteed for the load, p L 、p Cis the weight coefficient, which indicates the importance of the final planning scheme to the power supply path and budget cost; L indicates the total length of the power supply path; C indicates the total budget cost required for planning; represents the length of the power supply path for load l guaranteed by power source s; w l Indicates the importance level of the load node; Indicates the new construction cost of lines, guaranteed power sources and substations; Indicates the upgrade costs of lines, guaranteed power supplies, and substations; They are all binary variables, indicating whether the resource is newly added; They are all binary variables, indicating whether the resource is upgraded;

[0112] The multi-level protection constraints of the important loads are as follows:

[0113]

[0114] Among them, l is the load index, s is the power index, and i / j / k is the node index; represents the active power flowing through the line supplied by power supply s to load 1; p l represents the active power of load l; Indicates the active power supplied by power source s to load l; a ij is a binary variable, indicating whether line (i, j) is in an upgraded state, that is, whether line (i, j) has been upgraded / built; c l 、c s 、c lj Indicates the voltage level to which the component belongs; s is a binary variable, indicating whether the power supply s is added / upgraded; L i，j Indicates the length of the line; is a binary variable, indicating whether line (i, j) is energized when load 1 is powered by power source s; i，j Indicates that if line (i, j) is in the upgraded state, the weight of the line length is 1, otherwise it is 0;

[0115] The planning variable logic and budget constraints are as follows:

[0116]

[0117] C≤C max (twenty two)

[0118] Among them, ε C , S C , Respectively represent the new line, power source, and substation set to be built; ε0, S0, They represent the sets of lines, power sources and substations that do not need to be newly built; εup , S up , Respectively represent the upgraded lines, power sources, and substations; β b It is a binary variable, indicating whether substation b is upgraded.

[0119] The specific process of using the device of the embodiment of the present invention to carry out regional power grid resilience planning based on the principle of differentiated supply guarantee of important loads is similar to the aforementioned method embodiment and will not be repeated here.

[0120] To sum up, the embodiment of the present invention is a multi-level strong local power grid boundary division and resource allocation optimization method based on the principle of differentiated supply guarantee for important loads, which takes into account two resilience improvement measures: grid reinforcement and power supply point configuration and capacity determination. At the same time, after a large power shortage occurs, the local power grid continues to supply power to important loads, thereby reducing the economic losses and social impacts caused by power outages. The method is easy to deploy and implement, and has strong autonomy and practicality.

[0121] Those skilled in the art can understand that the accompanying drawings are only schematic diagrams of an embodiment, and the modules or processes in the accompanying drawings are not necessarily required to implement the present invention.

[0122] It can be known from the description of the above implementation methods that those skilled in the art can clearly understand that the present invention can be implemented by means of software plus a necessary general hardware platform. Based on such an understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which can be stored in a storage medium such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in the various embodiments of the present invention or certain parts of the embodiments.

[0123] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device or system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. The device and system embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0124] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for planning resilience of a regional power grid based on the principle of differentiated supply guarantee of important loads, characterized in that: include: Set up the principle of differentiated supply guarantee for important loads in the zoned power grid and the principle of multi-level power supply guarantee; Analyze the upgrade requirements of existing components in the sub-grid and determine the location of new components; A planning model is constructed based on the principle of differentiated supply of important loads, the principle of multi-level power supply guarantee and the location of new components, and the planning model is solved to obtain a resilience planning strategy.

2. The method according to claim 1, characterized in that: The principle of differentiated supply guarantee for important loads in the zoned power grid and the principle of multi-level power supply guarantee include: The principle of differentiated supply guarantee for important loads in the zoned power grid includes: the guaranteed power supply for super-important loads is located at the level where the load is located; the guaranteed power supply for first-level important loads is located at the level where the load is located and the level above; the guaranteed power supply for second-level important loads is located at the level above the level where the load is located; The principles for setting up multi-level power supply guarantees in zoned power grids include: important loads cannot be guaranteed by lower-level power supplies, that is, the loads cannot be guaranteed through lines at the next voltage level, and the power supply cannot be guaranteed through lines at the previous voltage level.

3. The method according to claim 2, characterized in that The constraints corresponding to the principle of differentiated supply guarantee for important loads and the principle of multi-level power supply guarantee are as follows: In the formula, represents the number of guaranteed power sources for load l at level c, is a binary variable, indicating whether the load l is protected by the power source s. They represent the super important load set, the first important load set, and the second important load set respectively; c is the level index; This constraint indicates the number of guaranteed power sources for load l at level c. It is equal to the sum of the protection conditions of all power sources for the load at this level, and according to the principle of power supply planning for important loads of different levels, it ensures that any important load can obtain at least one guaranteed power source.

4. The method according to claim 2, characterized in that: The analysis of the upgrade requirements of existing components in the zoned power grid and determination of the locations of new components include: Analyze the existing grid structure, substation conditions and power supply security, analyze the existing component upgrade needs based on the types of extreme disasters that may occur in the corresponding areas, determine the line, substation, power supply upgrade plan and budget, refer to historical experience data based on heuristic methods combined with geographical constraints of line planning and network connectivity indicators, identify weak links, and determine the location of new components, which includes new line corridors, substation locations and power supply locations.

5. The method according to claim 4, characterized in that The planning model is constructed based on the differentiated supply guarantee principle of important loads, the multi-level power supply guarantee principle and the location of new components, and the planning model is solved to obtain a resilience planning strategy, including: The objective function of the planning model is set based on the differentiated supply guarantee principle of important loads and the multi-level power supply guarantee principle, and the multi-level guarantee constraints, planning variable logic and budget constraints of important loads are set; Based on the multi-level protection constraints of the important loads, the planning variable logic and the budget constraints, a solver is used to solve the objective function of the planning model to obtain a resilience planning strategy, which includes the capacity, location and type of new power sources at each voltage level, status information of line upgrades / reinforcement, and the protection relationship between each power source and the important loads.

6. The method according to claim 5, characterized in that The objective function of the planning model is: max R-p L L-p C C (3) Among them, R represents the weighted sum of the number of guaranteed power sources, that is, the number of power sources guaranteed for the load, p L 、p C is the weight coefficient, which indicates the importance of the final planning scheme to the power supply path and budget cost; L indicates the total length of the power supply path; C indicates the total budget cost required for planning; represents the length of the power supply path for load l guaranteed by power source s; w l Indicates the importance level of the load node; Indicates the new construction cost of lines, guaranteed power sources and substations; Indicates the upgrade costs of lines, guaranteed power supplies, and substations; They are all binary variables, indicating whether the resource is newly added; They are all binary variables, indicating whether the resource is upgraded; The multi-level protection constraints of the important loads are as follows: Among them, l is the load index, s is the power index, and i / j / k is the node index; represents the active power flowing through the line supplied by the power source s to the load l; p l represents the active power of load l; Indicates the active power supplied by power source s to load l; a ij is a binary variable, indicating whether line (i, j) is in an upgraded state, that is, whether line (i, j) has been upgraded / built; c l 、c s 、c ij Indicates the voltage level to which the component belongs; s is a binary variable, indicating whether the power supply s is added / upgraded; L i，j Indicates the length of the line; is a binary variable, indicating whether line (i, j) is energized when load l is powered by power source s; i，j Indicates that if line (i, j) is in the upgraded state, the weight of the line length is 1, otherwise it is 0; The planning variable logic and budget constraints are as follows: C≤C max (22) Among them, ε C , S C , Respectively represent the new line, power source, and substation set to be built; ε0, S0, They represent the sets of lines, power sources and substations that do not need to be newly built; ε up , S up , Respectively represent the upgraded lines, power sources, and substations; β b It is a binary variable, indicating whether substation b is upgraded.

7. A zoned power grid resilience planning device based on the principle of differentiated supply guarantee for important loads, characterized in that: include: The supply guarantee principle and security principle setting module is used to set the differentiated supply guarantee principle and multi-level power supply security principle for important loads in the zoned power grid; A new component location determination module is used to analyze the upgrade requirements of existing components in the zoned power grid and determine the location of new components; The resilience planning strategy determination module is used to build a planning model based on the differentiated supply guarantee principle of important loads, the multi-level power supply guarantee principle and the location of new components, solve the planning model, and obtain a resilience planning strategy.

8. The device according to claim 7, characterized in that The supply guarantee principle and guarantee principle setting module are used to set the differentiated supply guarantee principle of important loads in the zoned power grid, including: the guaranteed power supply of the super important load is located at the level where the load is located; the guaranteed power supply of the first important load is located at the level where the load is located and the level above; the guaranteed power supply of the second important load is located above the level where the load is located; The principles for setting up multi-level power supply guarantees in zoned power grids include: important loads cannot be guaranteed by lower-level power supplies, that is, the loads cannot be guaranteed through lines at the next voltage level, and the power supply cannot be guaranteed through lines at the previous voltage level.

9. The device according to claim 8, characterized in that The module for determining the location of new components is used to analyze the existing grid structure, substation conditions and power supply conditions, analyze the upgrade needs of existing components based on the types of extreme disasters that may occur in the corresponding areas, determine the line, substation, power supply upgrade plan and budget, refer to historical experience data based on heuristic methods combined with geographical constraints of line planning and network connectivity indicators, identify weak links, and determine the location of new components. The location of new components includes the location of new line corridors, substations and power sources.

10. The device according to claim 9, characterized in that The resilience planning strategy determination module is used to set the objective function of the planning model based on the differentiated supply guarantee principle of important loads and the multi-level power supply guarantee principle, and to set the multi-level guarantee constraints, planning variable logic and budget constraints of important loads; Based on the multi-level protection constraints of the important loads, the planning variable logic and the budget constraints, a solver is used to solve the objective function of the planning model to obtain a resilience planning strategy, which includes the capacity, location and type of new power sources at each voltage level, status information of line upgrades / reinforcement, and the protection relationship between each power source and the important loads.

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