Water pressure management planning system, method and program

Abstract

To ensure hydraulic stability while minimizing the increase in the number of pressure reducing valves installed.SOLUTION: A water pressure management planning system 1 includes a storage device 10 and a processor 20 and creates a plan for managing water pressure in a water pipe network. The storage device stores a program, pipe network data 11 of a water pipe network, and demand data 12. The processor executes the program to function as a pressure reducing plan creating unit 21 that drafts a pressure reducing valve installation plan for installing a pressure reducing valve in the water pipe network. The pressure reducing plan creating unit has a water pressure increase area extraction unit 23 that extracts water pressure increase areas in the water pipe network where water pressure will increase in the future based on the pipe network data and the demand data, and a pressure reducing valve installation optimization unit 24 that determines the position to install a pressure reducing valve in a boundary pipe that connects the inside and outside of the water pressure increase area.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a water pressure management planning system, method, and program. [Background technology]

[0002] Among water pipe networks (hereafter referred to as "pipe networks"), there are some that use gravity flow systems to distribute water by utilizing the potential energy of elevated water reservoirs without using pumps. The water pressure at the end of a gravity flow system pipe network depends on the amount of demand (the amount of flow in the pipes). Even if water pressure is currently managed appropriately up to the end of the pipe network, if the population of some of the areas where the pipe network is installed decreases in the future, there is a concern that water pressure will increase in the areas with reduced population as demand decreases.

[0003] In this way, with existing facilities, the water pressure balance assumed for each facility is disrupted, and it may be necessary to install new pressure reducing valves to adjust the water pressure balance, or to reconstruct the pipe network by resetting existing pressure reducing valves.

[0004] Patent Document 1 describes a main line search system that extracts the main route between a specified water supply point and a water source as a main line. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2001-329575 A Summary of the Invention [Problem to be solved by the invention]

[0006] The main line search system in Patent Document 1 cannot extract a framework that takes into account the hydraulic characteristics of the entire pipeline. Furthermore, Patent Document 1 does not mention any technology for utilizing the extracted main lines, such as the installation of pressure reducing valves in the main lines.

[0007] Therefore, the present invention has been made in consideration of the above problems, and an object of the present invention is to provide a technique for ensuring hydraulic stability while suppressing an increase in the number of pressure reducing valves installed. [Means for solving the problem]

[0008] In order to achieve the above object, the present invention provides a water pressure management planning system comprising a storage device and a processor, which plans to manage the water pressure of a water pipe network, wherein the storage device stores a program, pipe network data of the water pipe network, and demand data, and the processor executes the program to function as a pressure reducing planning unit that plans a pressure reducing valve installation plan to install a pressure reducing valve in the water pipe network, and the pressure reducing planning unit comprises a water pressure increase area extraction unit that extracts water pressure increase areas in the water pipe network where water pressure will increase in the future based on the pipe network data and the demand data, and a pressure reducing valve installation optimization unit that determines the location to install the pressure reducing valve in a boundary pipe connecting the inside and outside of the water pressure increase area. Effect of the Invention

[0009] According to the present invention, hydraulic stability can be ensured while suppressing an increase in the number of pressure reducing valves installed. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a configuration diagram of a water pressure management plan formulation system in a first embodiment. [Diagram 2] FIG. 4 is a diagram showing a table storing pipeline (link) data in the first embodiment. [Diagram 3] FIG. 2 is a diagram showing a table storing pipeline (node) data in the first embodiment. [Figure 4] FIG. 4 is a diagram showing a table storing demand data in the first embodiment. [Diagram 5] 5 is a flowchart showing a pressure reduction plan formulation process in the first embodiment. [Figure 6] 5 is a flowchart showing a pipeline model generation process in the first embodiment. [Figure 7] 5 is a flowchart showing an increased water pressure area extraction process in the first embodiment. [Figure 8] 5 is a flowchart showing an increased water pressure area extraction process in the first embodiment. [Figure 9] 5A to 5C are diagrams for explaining the process of searching for an area of ​​increased water pressure in the first embodiment. [Figure 10] 6A to 6C are diagrams showing calculation results of the water pressure increase area extraction process in the first embodiment. [Figure 11] 4 is a flowchart showing an optimization model construction process in the first embodiment. [Figure 12] 4 is a flowchart showing an optimization process in the first embodiment. [Figure 13] FIG. 4 is a diagram for explaining details of an optimization process in the first embodiment. [Figure 14] FIG. 4 is a screen configuration diagram of an input / output unit in the first embodiment. [Figure 15] FIG. 11 is a configuration diagram of a water pressure management plan formulation system in a second embodiment. [Figure 16] 10 is a flowchart showing a pressure reduction plan formulation process in a second embodiment. [Figure 17] 10 is a flowchart showing a contracted pipe network generation process in the second embodiment. [Figure 18] FIG. 11 is a diagram for explaining a contracted pipe network in a second embodiment. [Figure 19] FIG. 11 is a screen configuration diagram of an input / output unit in the second embodiment. [Figure 20] 13 is a flowchart showing a pressure reduction plan formulation process in a third embodiment. [Figure 21] FIG. 13 is a diagram showing a method for calculating a water pressure ratio in the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, specific examples of the water pressure management planning system and method according to the embodiment of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the examples, but is defined by the claims. EXAMPLES

[0012] FIG. 1 is a configuration diagram of a water pressure management plan formulation system in the first embodiment.

[0013] The water pressure management planning system 1 includes a storage device 10, a processor 20, and an input / output unit 30. The water pressure management planning system 1 creates a plan to manage the water pressure of a water pipe network (hereinafter also referred to as a pipe network) that distributes water by utilizing the potential energy of an elevated water reservoir without using a pump.

[0014] The storage device 10 stores a program, pipe network data 11 of the pipe network, and demand data 12. The storage device 10 is, for example, a hard disk drive or a solid state drive (SSD). The storage device 10 may include a memory. The pipe network data 11 will be described later with reference to Figs. 2 and 3. The demand data 12 will be described later with reference to Fig. 4. The recording device (storage medium) 10 non-temporarily stores computer programs or data. At least a portion of the computer programs and data stored in the memory or storage unit can be stored in the recording device 10.

[0015] The processor 20 executes a program stored in the storage device 10 to function as a pressure reducing plan planning unit 21 that plans to install pressure reducing valves in a pipeline, and a pipeline calculation unit 22. The processor 20 may be configured with, for example, an FPGA (Field Programmable Gate Array) or a GPU (Graphic Processing Unit).

[0016] The pressure reduction plan formulation unit 21 has a water pressure increase area extraction unit 23 and a pressure reducing valve installation optimization unit 24.

[0017] The water pressure increase area extraction unit 23 extracts, based on the pipe network data 11 and the demand data 12, areas in the pipe network where the future water pressure will increase with a similar tendency.

[0018] The pressure reducing valve installation optimization unit 24 develops a pressure reducing valve installation plan for installing pressure reducing valves in boundary pipelines connecting the inside and outside of an area with increased water pressure.

[0019] The pipe network calculation unit 22 executes a pipe network model generation process for generating a pipe network model for calculation based on the pipe network data 11, and executes pipe network calculations.

[0020] The input / output unit 30 has an input unit to which data is input from a user, and an output unit to which various output data is output to the user. The input unit may be, for example, a keyboard, a touch panel, or a mouse. The output unit may be, for example, a display or a printer.

[0021] FIG. 2 is a diagram showing a table storing pipeline (link) data in the first embodiment.

[0022] The pipe network data 11 may include various data on pipelines, pressure reducing valves, pumps, connection points, and water facilities (reservoirs or supply sources). The pipe network data 11 is displayed as a graph network on the screen of the input / output unit 30. Of the pipe network data 11, the pipelines, pressure reducing valves, and pumps are displayed as links. The pipe network data 11 includes at least one water facility, pipelines, and connection points.

[0023] The pipeline data includes IDs of the start and end points, the length indicating the specifications of the pipeline, the diameter, the pipeline resistance, and the open / closed state attributes. Furthermore, the pipeline data may include the coordinates of the midpoints so that the pipeline can be represented as a broken line when drawn.

[0024] The data for the pressure reducing valve includes the IDs of the start and end points, as well as the valve diameter and secondary pressure, which indicate the specifications of the pressure reducing valve. The secondary pressure is the water pressure at the node set on the end side during the pipe network calculation.

[0025] The pump data includes IDs of the start point and end point, and discharge pressure and flow rate indicating specifications. The pipe network data 11 does not necessarily need to include pump data.

[0026] FIG. 3 is a diagram showing a table storing pipe network (node) data in the first embodiment.

[0027] The pipe network data 11 may further include various data on connection points and water facilities. In the pipe network data 11, demand points, water reservoirs, and supply sources are displayed as nodes.

[0028] The data of the connection point indicates the customer (or customer group) to which water demand is assigned, or the connection point between pipelines. The data of the connection point includes the elevation, demand amount, and coordinates as attributes. The initial value of the demand amount is the value for the period t=0 described later.

[0029] A water facility includes a reservoir or a source. Each facility has a common ID. The data required for the calculation of the pipe network include at least the reservoir elevation (head in case of a source), the lower limit water level, the upper limit water level, and the capacity.

[0030] FIG. 4 is a diagram showing a table storing demand data in the first embodiment.

[0031] The demand data 12 includes node names and demand data for each period. The periods are managed by integers starting from 0. A correspondence table with fiscal years may be stored in the storage device 10, with "0" representing 2020, "1" representing 2035, etc.

[0032] FIG. 5 is a flowchart showing the pressure reduction plan formulation process in the first embodiment.

[0033] The pipe network calculation unit 22 reads the pipe network data 11 and executes a pipe network model generation process for generating a pipe network model for calculation (pipe network model generation process, S501). The process contents will be described later with reference to FIG.

[0034] Next, the water pressure increase area extraction unit 23 extracts an area of ​​increased water pressure (water pressure increase area extraction process, S502). Specifically, the water pressure increase area extraction unit 23 constructs an area of ​​increased water pressure consisting of multiple nodes that is to be subjected to pressure reduction. Each area of ​​increased water pressure is expressed as a set of nodes. The i-th area of ​​increased water pressure is defined as Ai={v_x|v_x is a node showing a similar water pressure increase trend}. The processing contents will be described later with reference to Figs. 7 and 8.

[0035] Next, the pressure reducing valve installation optimization unit 24 constructs a pressure reducing valve installation optimization model (S503). Specifically, the pressure reducing valve installation optimization unit 24 constructs an optimization problem for determining whether or not to install a pressure reducing valve on a pipeline connecting the inside and outside of an area with increased water pressure, and stores the problem in memory. The processing content will be described later with reference to FIG. 11.

[0036] Next, the pressure reducing valve installation optimization unit 24 solves the constructed optimization problem and creates a future pressure reducing valve installation plan (S504). The processing content will be described later with reference to FIG.

[0037] Next, the input / output unit 30 outputs the pipeline network data 11 and the demand data 12 at the time when the optimization process is completed (S505). The output format may be the table format shown in Figs.

[0038] FIG. 6 is a flowchart showing a pipeline model generation process in the first embodiment.

[0039] The pipeline calculation unit 22 reads node data (connection points, reservoirs, and supply sources) for pipeline calculation into memory (S601).

[0040] The pipeline calculation unit 22 reads link data (pipes, pressure reducing valves, pumps) for pipeline calculation into the internal memory (S602).

[0041] The pipe network calculation unit 22 converts the node data and link data read into the memory into a pipe network model format (S603). The conversion is performed by generating data in which the values ​​in the tables shown in Figs. 2 to 4 have been rearranged so that the data conforms to the input format of existing pipe network calculation software such as EPANET. The data is converted into a text file format in which items (such as connection points) and attribute values ​​(such as elevation and / or demand) correspond to each other for each data item, such as JUNCTIONS for connection points and TANKS for water reservoirs. The specifications are in accordance with those that have been made public. The conversion process is not described here because it only involves converting the corresponding attribute values ​​into a default order and does not involve any complicated processing.

[0042] The pipeline calculation unit 22 outputs the pipeline model (S604). The pipeline model may be stored as a text file in the storage device 10, or may be stored in the internal memory in text format. The model created according to the current demand is defined as the current demand pipeline model.

[0043] FIG. 7 is a flowchart showing the process of extracting an area of ​​increased water pressure in the first embodiment.

[0044] The water pressure increase area extraction unit 23 sets various conditions for the water pressure increase area extraction process (S701). The set of various conditions may be stored in the storage device 10 in a format such as a text file. The set of various conditions includes at least a threshold value (real number), a current period, and a future period for calculation. The threshold value (real number) includes a threshold value (real number) for determining that the water pressure increase trend is similar, and a threshold value (real number) for determining that there is a water pressure increase. The current period and the future period may be the current period (t=0 as a reference) and the future period (t=1, 2, ...) for calculating the amount of water pressure increase.

[0045] Next, the water pressure increase area extraction unit 23 reads the pipe network model created in S604 of FIG. 6 (S702).

[0046] Next, the water pressure increase area extraction unit 23 inputs the pipe network models of current demand and future demand to the pipe network calculation unit 22 and causes it to execute a pipe network calculation (S703). The pipe network calculation unit 22 constructs the current demand pipe network model created in S603 of Fig. 6, and a future demand pipe network model in which only the demand amount is replaced with the data for the future period of Fig. 4, performs pipe network calculations for each, and stores the results (water pressure at each connection point, flow rate of the pipeline, etc.) in internal memory. Existing pipe network calculation software (such as EPANET) may be used for the pipe network calculation.

[0047] Next, the water pressure increase area extraction unit 23 stores the amount of water pressure increase (S704). Specifically, the water pressure increase area extraction unit 23 calculates the amount of increase in water pressure (pressdiff(v_i)) between the current demand pipe network model and the future demand pipe network model for each connection point v_i. The water pressure increase area extraction unit 23 stores this in an internal memory as a table with the connection point ID as a key and the amount of increase in water pressure as a value.

[0048] Next, the water pressure increase area extraction unit 23 generates an undirected graph G=(V,E) for the search process on the graph (S705). At this time, "V" may be generated from node data of the pipe network data, and "E" may be generated from link data. Each connection relationship is set based on the start point and end point included in the link data.

[0049] FIG. 8 is a flowchart showing the process of extracting an area of ​​increased water pressure in the first embodiment.

[0050] Next, the water pressure increase area extraction unit 23 lists search start point candidates (S801). The water pressure increase area extraction unit 23 may set all nodes where the water pressure increase is equal to or greater than the threshold set in S701 as search start point candidates. Note that the behavior during search (the range indicated by the dashed line in FIG. 8) will be explained further in FIG. 9.

[0051] Next, the water pressure increase area extraction unit 23 selects one search starting point (S802).

[0052] Next, the water pressure increase area extraction unit 23 generates an area of ​​increased water pressure using only the initial value search starting point (S803).

[0053] Next, the water pressure increase area extraction unit 23 acquires the amount of water pressure increase at the adjacent point (S804).

[0054] Next, the water pressure increase area extraction unit 23 determines whether the water pressure increase trends are similar (S805). The water pressure increase area extraction unit 23 may determine whether the water pressure increase amount is equal to or greater than a threshold. If the determination result of S805 is false (S805: NO), the water pressure increase area extraction unit 23 proceeds to S807.

[0055] If the determination result in S805 is true (S805: YES), the water pressure increase area extraction unit 23 adds the area to the water pressure increase area and removes it from the search start point candidates (S806), and proceeds to S807.

[0056] Next, the water pressure increase area extraction unit 23 judges whether there is an adjacent point (S807). If the judgment result of S807 is true (S807: YES), the water pressure increase area extraction unit 23 sets the adjacent point as the starting point of the next search (S808).

[0057] If the result of the determination in S807 is false (S807: NO), the water pressure increase area extraction unit 23 generates water pressure increase area data (S809). The format of the area data will be described later with reference to FIG.

[0058] Next, the water pressure increase area extraction unit 23 determines whether there is a search start point candidate (S810). If the determination result of S810 is true (S810: YES), the water pressure increase area extraction unit 23 returns to S802. If the determination result of S810 is false (S810: NO), the water pressure increase area extraction unit 23 ends the water pressure increase area extraction process.

[0059] FIG. 9 is a diagram for explaining the process of searching for an area with increased water pressure in the first embodiment.

[0060] As an example, a case will be described where the threshold for determining a water pressure increase is 8 m. As shown in FIG. 9(a), the water pressure increase area extraction unit 23 sets nodes where the water pressure increase is 8 m or more as search start point candidates V'. Note that V' is a subset of V.

[0061] Next, the water pressure increase area extraction unit 23 arbitrarily selects one search starting point vi∈V′ as shown in Fig. 9(b) to generate an area of ​​increased water pressure. The generated area of ​​increased water pressure is denoted by a set {vi}.

[0062] Next, the water pressure increase area extraction unit 23 checks the water pressure increase amount of adjacent points, and if the increase trends are similar, adds them to the water pressure increase area, as shown in Figure 9 (c). Here, the equation for determining whether the water pressure increase trends of node vi and node vj are similar is the following equation (1). In equation (1), a "small value" is used to make the determination, but any value may be stored in the storage device 10 and used. |press diff (vi)-press diff (vj)|≦small value …(1)

[0063] The water pressure increase area extraction unit 23 extracts the water pressure increase area {vi, v 3 i, ...}, and the points added to the area of ​​increased water pressure are removed from the search starting point candidates. Note that it is also possible to add points whose water pressure increase is equal to or greater than the threshold without performing the similarity judgment.

[0064] Next, the water pressure increase area extraction unit 23 ends the search when there are no points with similar water pressure increase trends among the adjacent points, as shown in Fig. 9(d). If there are search start point candidates remaining, the water pressure increase area extraction unit 23 arbitrarily selects one new search start point and executes the same process.

[0065] FIG. 10 is a diagram showing the calculation results of the water pressure increase area extraction process in the first embodiment.

[0066] Figure 10(a) is an example of a table that stores the water pressure increase for each fiscal year, with node names as keys. For example, if the period number is "2", the water pressure increase (unit: m) from period 0 to period 2 of node "j00001" is "5", and the water pressure increase (unit: m) from period 0 to period 2 of node "j00002" is "10".

[0067] 10(b) is an example of a table in which the key is the increased water pressure area number (the number is an arbitrary integer) and the value is a set of node IDs belonging to that increased water pressure area. For example, when the increased water pressure area number is "1", the set of node IDs belonging to the increased water pressure area is {j10100, j10101, ...}.

[0068] FIG. 11 is a flowchart showing the optimization model construction process in the first embodiment.

[0069] The pressure reducing valve installation optimization unit 24 sets conditions for the optimization model construction process (S1101). Specifically, the pressure reducing valve installation optimization unit 24 reads the upper and lower limits of the water pressure and the upper limit of the water pressure increase amount stored in the storage device 10 as constraints for optimization.

[0070] Next, the pressure reducing valve installation optimization unit 24 reads the pipe network model generated in FIG. 6 into the memory (S1102).

[0071] Next, the pressure reducing valve installation optimization unit 24 reads the water pressure increase area data and the water pressure increase data generated in FIG. 8 into memory (S1103).

[0072] Next, the pressure reducing valve installation optimization unit 24 extracts pipelines that connect the inside and outside of the area of ​​increased water pressure (hereinafter referred to as boundary pipelines) and sets them as candidates for installing a pressure reducing valve (S1104). At this time, the pipeline data is read line by line, and for each end point (start point or end point), a pipeline ID is extracted in which one end point belongs to any area of ​​increased water pressure and the other end point does not belong to any area of ​​increased water pressure.

[0073] Next, the pressure reducing valve installation optimization unit 24 constructs an optimization model (decision variables, objective function, constraints) shown in FIG. 12 (to be described later) (S1105). Specifically, the pressure reducing valve installation optimization unit 24 sets, as a decision variable, a variable that determines whether the pipeline is used, the pressure reducing valve (forward direction), the pressure reducing valve (reverse direction), or closed for each extracted boundary pipeline. The pressure reducing valve (forward direction) may be the direction in which the pipeline moves from the start point to the end point, and the pressure reducing valve (reverse direction) may be the direction in which the pipeline moves from the end point to the start point. Furthermore, the pressure reducing valve installation optimization unit 24 sets, as a decision variable, the initial period in which the pressure reducing valve is installed (remains until the end after installation). Furthermore, the pressure reducing valve installation optimization unit 24 sets, as a decision variable, the secondary pressure at the time of installing the pressure reducing valve (water pressure after pressure reduction).

[0074] The pressure reducing valve installation optimization unit 24 sets upper and lower limit constraints on the water pressure in the future pipeline model for nodes that do not belong to any water pressure increase area. The pressure reducing valve installation optimization unit 24 sets an objective function consisting of a weighted sum of the pressure reducing valve installation cost, the amount of flow direction change, and the amount of water pressure increase.

[0075] The pressure reducing valve installation optimization unit 24 determines, as a decision variable, the following x for each boundary pipeline (a pipeline having one end point that is a node in the area of ​​increased water pressure and the other end point that is a node outside the area of ​​increased water pressure): pi ~s tpi Set x pi For ∈{0,1}, "0" means closed and "1" means pipeline is in use. x pif For ∈{0,1}, "0" means no pressure reducing valve is installed (pipe is used as is), and "1" means a pressure reducing valve is installed in the forward direction (same diameter as the pipe). pib For ∈{0,1}, "0" means no pressure reducing valve is installed (pipe is used as is), and "1" means a pressure reducing valve is installed in the reverse direction (same diameter as the pipe). pi ∈{0,1,2,…} indicates the period during which the pressure reducing valve is installed (remains until the end after installation). For example, as a result of the optimization calculation, t pi If the calculation is x = 1, the pressure reducing valve is not installed until period 0, and x from period 1 onwards pi , x pif , x pib A pressure reducing valve is installed in accordance with the conditions shown in s. t ∈R+ In the case of , the secondary pressure setting value in period t after the pressure reducing valve is installed in the pipeline pi. However, R + is the set of any positive real numbers.

[0076] The pressure reducing valve installation optimization unit 24 restricts the selection of only one of the following for the pipeline pi: closed, pipeline only (without pressure reducing valve), installation of a forward pressure reducing valve, or installation of a reverse pressure reducing valve. To express this, a constraint equation is determined in which the value of each decision variable is 1 or less. This is the following equation (2). x pi +x pif +x pib ≦1 …(2)

[0077] Furthermore, the pressure reducing valve installation optimization unit 24 uses, as a constraint, the water pressure press of a node vi that does not belong to the water pressure increase area in a period t, which is obtained by calculating the water network in the future water network model. future Set the upper and lower limits of (vi, t) (real numbers press_LB and press_UB), as shown in the following equation (3). press_LB≦press future (vi, t)≦press_UB …(3)

[0078] The pressure reducing valve installation optimization unit 24 sets a weighted sum of the water pressure increase, the amount of reverse flow change, and the pressure reducing valve installation cost (or the number of installations) as an objective function.

[0079] The pressure reducing valve installation optimization unit 24 adds a penalty when the future water pressure of a node vi belonging to any water pressure increase area is higher than the current water pressure by a threshold or more as the water pressure increase amount. This is shown in the following equation (4). weight×Σ t Σ vi max(press future (vi, t)-press init (vi)-Threshold, 0) …(4) In addition, weight is the weight (real number), press future (vi,t) is the future water pressure of vi in ​​period t, init(vi) shows the current water pressure at vi.

[0080] The pressure reducing valve installation optimization unit 24 adds a penalty when the signs of the future flow rate and the current flow rate of any pipeline p are different as the amount of flow direction change. This is shown in the following equation (5). -1×weight×Σ t Σ p min(flow future (p, t)-flow init (p),0) …(5) Furthermore, flow future (p, t) is the flow rate of pi during period t, init (p) indicates the current flow rate of pi. For example, if the future flow rate is a positive flow rate (the sign is positive) and the current flow rate is a reverse flow (the sign is negative), the min function will be a negative value, so it will be multiplied by -1 to become a penalty.

[0081] The pressure reducing valve installation optimization unit 24 adds up the cost according to the number of installed pressure reducing valves as the pressure reducing valve installation cost (or the number of installations), as shown in the following formula (6). weight×Σ xpif (x pif ·cost(PRV pi ))+Σ xpib (x pib ·cost(PRV pi )) …(6) Furthermore, x pif indicates whether a forward pressure reducing valve is installed, cost(PRV pi ) is a pressure reducing valve PRV i The unit price of x (stored in a table format from diameter to cost. When the unit price = 1, it is evaluated by the number of installations). pib indicates whether a reverse pressure reducing valve is installed, cost (PRV pi ) indicates whether or not a reverse pressure reducing valve is installed.

[0082] FIG. 12 is a flowchart showing the optimization process in the first embodiment.

[0083] The pressure reducing valve installation optimization unit 24 provisionally sets decision variables based on the behavior of the optimization algorithm (S1301). The optimization algorithm may be an existing algorithm capable of nonlinear optimization, such as a genetic algorithm.

[0084] Next, the pressure reducing valve installation optimization unit 24 sets an evaluation target period (S1302). Specifically, the pressure reducing valve installation optimization unit 24 calculates an objective function for all input periods (t=0, 1, 2, ...).

[0085] Next, the pressure reducing valve installation optimization unit 24 sets the demand amount according to the period t in the pipeline model (S1303). For example, when t=1, the demand amount of each node in the period t=1 is set in the connection point data based on the table in FIG.

[0086] Next, the pressure reducing valve installation optimization unit 24 calculates the decision variable (x pi ,x pif ,x pib ) and corrects the pipeline model (updates the link data) (S1304). pi If =1, do not process and x pi If x = 0, the open / close setting of the pipeline is changed to CLOSED. pif = 1 and t ≦ t pi In the case of x, the pipeline pi is deleted, and a pressure reducing valve having the same start point and end point is created and added to the pressure reducing valve data. pib = 1 and t ≦ t pi In this case, the pipe pi is deleted, and a pressure reducing valve with the start and end points reversed is created and added to the pressure reducing valve data. Here, the secondary pressure of the pressure reducing valve is s tpi The value of x pi Set the value to be the same as.

[0087] Next, the pressure reducing valve installation optimization unit 24 causes the pipe network calculation unit 22 to execute a pipe network calculation (S1305).

[0088] Next, the pipe network calculation unit 22 calculates the objective function (S1306). Based on the above-mentioned formulas (2) to (6), the objective function for each period t is calculated, and the sum is obtained.

[0089] Next, the pressure reducing valve installation optimization unit 24 judges whether the optimization process is completed (S1307). The judgment condition may be either that the loop is performed a predetermined number of times, or that the improvement amount of the objective function value at the time of the previous loop continues to be equal to or less than a predetermined value N times. If the judgment result of S1307 is false (S1307: NO), the pressure reducing valve installation optimization unit 24 returns to S1301, and if the judgment result of S1307 is true (S1307: YES), the optimization process is terminated.

[0090] FIG. 13 is a diagram for explaining details of the optimization process in the first embodiment.

[0091] As shown in (a), in the initial state before the optimization process is performed, i.e., in the state where the boundary pipeline' (position of the black valve) is extracted, the pressure reducing valve installation optimization unit 24 determines whether or not to install a pressure reducing valve at the position of the black valve, and searches for a combination of pressure reducing valves that minimizes the objective function (S1301 to S1306 in FIG. 12).

[0092] Next, as shown in (b), the pressure reducing valve installation optimization unit 24 sets the pipeline model for period t=1 generated by the optimization process. In this example, the pressure reducing valve installation optimization unit 24 installs pressure reducing valves in pipelines connecting to areas j2 and j5.

[0093] Next, the pressure reducing valve installation optimization unit 24 sets the pipeline model for period t=2 determined by the optimization process, as shown in (c). In this example, the pressure reducing valve installation optimization unit 24 installs additional pressure reducing valves in pipelines connected to areas (j4 and j7) where demand is significantly reduced.

[0094] FIG. 14 is a diagram showing the screen configuration of the input / output unit in the first embodiment.

[0095] The screen of the input / output unit 30 displays a pipe network layout 31 for each period and each indicator 32. The pipe network layout 31 may include a pipe network layout 33 showing the positions of pressure reducing valves and a pipe network layout 34 showing areas of increased water pressure. The indicators 32 may include a Pareto solution (a trade-off between cost and hydraulics).

[0096] A condition input field 35 in which various conditions for calculation are input by the user may be displayed on the screen of the input / output unit 30. For example, the conditions input in the condition input field 35 may be constraint conditions (a similarity judgment of a water pressure increase tendency, and a threshold value for judging a water pressure increase).

[0097] According to this configuration, the water pressure management plan making system 1 includes a storage device 10 and a processor 20, and makes a plan for managing the water pressure of a water pipe network. The storage device 10 stores a program, pipe network data 11 of the water pipe network, and demand data 12. The processor 20 executes the program to function as a pressure reducing plan making unit 21 that makes a pressure reducing valve installation plan for installing a pressure reducing valve in the water pipe network. The pressure reducing plan making unit 21 includes a water pressure increase area extraction unit 23 and a pressure reducing valve installation optimization unit 24. The water pressure increase area extraction unit 23 extracts water pressure increase areas in the water pipe network where water pressure will increase in the future, based on the pipe network data 11 and the demand data 12. The pressure reducing valve installation optimization unit 24 determines the position for installing a pressure reducing valve in a boundary pipe that connects the inside and outside of the water pressure increase area.

[0098] This makes it possible to extract areas of increased water pressure based on the pipeline data 11 and the demand data 12, and determine the locations at which pressure reducing valves should be installed in boundary pipelines. This makes it possible to ensure hydraulic stability while suppressing an increase in the number of pressure reducing valves installed.

[0099] The water pressure increase area extraction unit 23 extracts, as an area of ​​increased water pressure, a set of points where the difference between the current and future water pressures is equal to or greater than a predetermined threshold and where the water pressure increase trends are similar, based on the pipe network data 11 and the demand data 12. This makes it possible to appropriately extract areas of increased water pressure.

[0100] The pressure reducing valve installation optimization unit 24 determines the location where the pressure reducing valve should be installed in the boundary pipeline based on an optimization model including a decision variable that determines whether to close the boundary pipeline, install a pressure reducing valve, or maintain the pipeline, an objective function consisting of a weighted sum of the current and future water pressure increase amount, flow direction change amount, and the number of pressure reducing valves to be installed, and constraints that determine the upper and lower limits of water pressure. This makes it possible to determine the location where the pressure reducing valve should be installed based on the optimization model. EXAMPLES

[0101] Example 2 is an example in which the pipe network model is reduced. Hereinafter, Example 2 will be described with reference to the drawings, focusing only on the differences from Example 1.

[0102] FIG. 15 is a configuration diagram of a water pressure management plan formulation system in the second embodiment.

[0103] The processor 20 executes the program stored in the storage device 10 to function as a reduced pressure planning unit 21, a pipe network calculation unit 22, and also as a reduced pipe network generation unit 25.

[0104] The contracted pipe network generation unit 25 has a large diameter pipe selection unit 26, a skeleton pipe candidate extraction unit 27, and a skeleton pipe selection unit .

[0105] The large diameter pipe selection unit 26 extracts pipe networks having a predetermined diameter or more as large diameter pipe networks based on the pipe network data 11.

[0106] The skeleton pipeline candidate extraction unit 27 extracts skeleton pipeline candidates that are candidates for connecting large diameter pipe networks.

[0107] The skeleton pipeline selection unit 28 selects skeleton pipelines to be included in the contracted pipe network from among the skeleton pipeline candidates and stores them in the storage device 10 as contracted pipe network data (pipe network data 11).

[0108] FIG. 16 is a flowchart showing the pressure reduction plan formulation process in the second embodiment.

[0109] The contracted pipe network generation unit 25 executes a contracted pipe network generation process (S1700) to contract the pipe network between S501 and S502 in the first embodiment. Specifically, the contracted pipe network generation unit 25 contracts the pipe network model, leaving only the trunk line among the large diameter pipes and branch pipes. In the process after S502, the pressure reduction plan formulation process is executed using the contracted pipe network. Details of the contraction process will be described in FIG. 17.

[0110] FIG. 17 is a flowchart showing the contracted pipe network generation process in the second embodiment, and FIG. 18 is a diagram for explaining the contracted pipe network in the second embodiment.

[0111] The water pressure increase area extraction unit 23 reads the pipe network model output in S604 of FIG. 6 and the pipe network data 11, and creates a search graph (hereinafter referred to as initial graph G) by the same process as in S705 of FIG. 7 (S1801).

[0112] Next, the large-diameter pipe selection unit 26 selects a large-diameter pipe (S1802). Specifically, the large-diameter pipe selection unit 26 deletes pipelines with diameters less than a preset threshold (such as the lower limit of the diameter of the water distribution main), and for the remaining pipelines, sets each connection portion as a partial pipe network pn_i.

[0113] Next, the skeleton pipeline candidate extraction unit 27 generates skeleton pipeline candidates (S1803). Specifically, the skeleton pipeline candidate extraction unit 27 calculates the distance for each of the partial pipe networks pn_i and pn_j. At this time, the distance is the shortest distance on the initial graph G that connects vi∈Vpn_i and vj∈Vpn_j. Here, Vpn_i is a set of nodes that constitute the partial pipe network pn_i.

[0114] When calculating the shortest distance, the skeleton pipeline candidate extraction unit 27 may use a value in which the length is weighted by the inverse of the diameter, such as "length ÷ diameter", instead of the pipeline length. This makes the value smaller as the diameter increases, making it easier to select the route as the shortest route.

[0115] The skeleton pipeline candidate extraction unit 27 extracts the shortest path as a skeleton candidate pn_i_j (a pipeline on the shortest route connecting pn_i and pn_j).

[0116] Next, the skeleton pipeline selection unit 28 selects a skeleton pipeline (S1804). Specifically, the skeleton pipeline selection unit 28 selects a skeleton candidate of the shortest route connecting all partial pipe networks, and constructs a graph G' in which the partial pipe network pn_i is node Npn_i, and the link corresponding to the skeleton candidate npn_i_j is Epn_i_j. At this time, the distance of the link Epn_i_j is the same as the distance of the skeleton candidate npn_i_j. The skeleton pipeline selection unit 28 derives a minimum spanning tree in the graph G', and the links included in the minimum spanning tree are set as skeleton pipelines to be ultimately left after contraction.

[0117] Next, the input / output unit 30 outputs a pipe network model that leaves only the pipes included in the partial pipe network and the skeleton pipe network (S1805). At this time, the demand of a connection point that is not included in the contracted pipe network may be added to the demand of the closest connection point.

[0118] FIG. 19 is a diagram showing the screen configuration of the input / output unit in the second embodiment.

[0119] In addition to the pipeline layout 31 for each period and the indicators 32, the screen of the input / output unit 30 may further display the results of the pipeline contraction.

[0120] The results of the pipe network reduction may include an initial pipe network 36 before reduction, a skeleton pipe network 37 after reduction, and a scatter plot 38 (water pressure distribution, etc.) that visualizes the accuracy (evaluation) of the reduction result.

[0121] A selection condition input field 39 in which the user inputs the selection conditions may be displayed on the screen of the input / output unit 30. For example, the conditions input in the selection condition input field 39 may be a diameter threshold value.

[0122] According to this configuration, the processor 20 executes a program to further function as a reduced pipe network generating unit 25 that generates a reduced pipe network by reducing a water pipe network. The reduced pipe network generating unit 25 has a large diameter pipe network extracting unit 26, a skeleton pipeline candidate extracting unit 27, and a skeleton pipeline selecting unit 28. The large diameter pipe network extracting unit 26 extracts a pipe network having a predetermined diameter or more as a large diameter pipe network based on the pipe network data 11. The skeleton pipeline candidate extracting unit 27 extracts skeleton pipeline candidates that are candidates for connecting large diameter pipe networks. The skeleton pipeline selecting unit 28 selects skeleton pipelines to be included in the reduced pipe network from the skeleton pipeline candidates.

[0123] This makes it possible to reduce the size of the water pipe network and shorten the calculation time. EXAMPLES

[0124] Example 3 is an example in which the method of setting the cost function is changed from Example 2. Hereinafter, Example 3 will be described with reference to the drawings, focusing only on the differences from Example 2.

[0125] FIG. 20 is a flowchart showing the pressure reduction plan formulation process in the third embodiment, and FIG. 21 is a diagram showing a method of calculating the water pressure ratio in the third embodiment.

[0126] The pipeline calculation unit 22 executes pipeline calculations using a future pipeline model (S2101).

[0127] Next, the pressure reducing valve installation optimization unit 24 extracts the water pressure on the end point side of the boundary pipeline (S2102).

[0128] Next, the pressure reducing valve installation optimization unit 24 calculates the water pressure ratio (maximum water pressure / minimum water pressure for one day) for each boundary pipeline (S2103). For example, the pressure reducing valve installation optimization unit 24 determines whether the water pressure ratio is equal to or greater than the threshold value, as shown in FIG.

[0129] Next, the pressure reducing valve installation optimization unit 24 sets a cost function according to the water pressure ratio (S2104). At this time, the installation cost of a pressure reducing valve to be installed in a pipeline pi whose water pressure ratio is equal to or greater than a threshold value is calculated by cost' in the following formula (7). weight×Σ xpif,xpib (x pif ·cost´(PRV pi )+x pib ·cost´(PRV pi )) …(7) The installation cost of a pressure reducing valve to be installed in a pipeline pi whose water pressure ratio is equal to or greater than a threshold value is calculated using cost'' in the following formula (8). weight×Σ xpif,xpib (x pif ·cost´´(PRV pi )+x pib ·cost´´(PRV pi )) …(8) In addition, cost' is the installation cost of a pressure reducing valve for remote monitoring and control as a "remote monitoring and control pressure reducing valve", and cost'' is the installation cost of a pressure reducing valve with a fixed secondary pressure as a "fixed set value pressure reducing valve".

[0130] According to this configuration, the objective function includes the installation costs of the remote monitoring and control reducing valve and the fixed set value reducing valve, which allows the installation locations of the reducing valves to be appropriately determined.

[0131] The present invention is not limited to the above-mentioned embodiment, but includes various modified examples. For example, the above-mentioned embodiment has been described in detail to clearly explain the present invention, and is not necessarily limited to those including all of the configurations described. Also, it is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. Also, it is possible to add, delete, or replace a part of the configuration of each embodiment with another configuration. [Explanation of symbols]

[0132] 1...water pressure management planning system, 10...storage device, 11...pipe network data, 12...demand data, 20...processor, 21...pressure reduction planning section, 23...water pressure increase area extraction section, 24...pressure reducing valve installation optimization section, 25...contracted pipe network generation section, 26...large diameter pipe selection section, 27...skeletal pipe candidate extraction section, 28...skeletal pipe selection section

Claims

1. A water pressure management planning system comprising a storage device and a processor, which plans to manage water pressure in a water pipe network, The storage device stores a program, pipe network data of the water pipe network, and demand data, The processor executes the program to function as a pressure reducing plan developing unit that develops a pressure reducing valve installation plan for installing pressure reducing valves in the water pipe network; The pressure reduction plan formulation unit a water pressure increase area extraction unit that extracts an area in the water pipe network where water pressure will increase in the future based on the pipe network data and the demand data; a pressure reducing valve installation optimization unit that determines a position where the pressure reducing valve is installed in a boundary pipe that connects the inside and outside of the water pressure increase area; A water pressure management planning system having the above structure.

2. The processor further functions as a reduced pipe network generation unit that generates a reduced pipe network by executing the program, The contracted pipe network generation unit includes: a large-diameter pipe network extraction unit that extracts a pipe network having a diameter equal to or larger than a predetermined diameter as a large-diameter pipe network based on the pipe network data; a skeleton pipeline candidate extraction unit that extracts skeleton pipeline candidates that are candidates for connecting the large diameter pipe networks; A skeleton pipeline selection unit that selects skeleton pipelines to be included in the contracted pipeline network from among the skeleton pipeline candidates. The water pressure management planning system according to claim 1 .

3. The water pressure increase area extraction unit extracts, based on the pipe network data and the demand data, a set of points where the current and future water pressure difference is equal to or greater than a predetermined threshold, or a set of points where the water pressure increase trend is similar, as the water pressure increase area. The water pressure management planning system according to claim 1 or 2.

4. The pressure reducing valve installation optimization unit determines a position to install the pressure reducing valve in the boundary pipeline based on an optimization model including a decision variable that determines whether to close the boundary pipeline, install the pressure reducing valve, or maintain the pipeline, an objective function consisting of a weighted sum of the current and future water pressure increase amount, the flow direction change amount, and the number of pressure reducing valves to be installed, and a constraint that determines the increase or decrease in water pressure. The water pressure management planning system according to claim 1 or 2.

5. The objective function includes the installation cost of the remotely monitored and controlled pressure reducing valve and the fixed set point pressure reducing valve. The water pressure management planning system according to claim 4.

6. A water pressure management planning method in which a water pressure management planning system plans a plan for managing water pressure in a water pipe network, comprising: a reduced pipe network generating step of generating a reduced pipe network by reducing the water pipe network; A pressure reducing plan formulation step of formulating a pressure reducing valve installation plan for installing a pressure reducing valve in the water pipe network, The contracted pipe network generating step includes: a large-diameter pipe network extraction unit that extracts a pipe network having a predetermined diameter or more as a large-diameter pipe network based on the pipe network data; a skeleton pipeline candidate extraction unit that extracts skeleton pipeline candidates that are candidates for connecting the large diameter pipe networks; a skeleton pipeline selection unit that selects skeleton pipelines to be included in the contracted pipeline network from among the skeleton pipeline candidates; The pressure reduction plan formulation step includes: a water pressure increase area extraction step of extracting a water pressure increase area in the water pipe network where water pressure will increase in the future based on the pipe network data and the demand data; a pressure reducing valve installation optimization step of determining a position where the pressure reducing valve is installed in a boundary pipe that connects the inside and outside of the water pressure increase area; A method for developing a water pressure management plan that includes:

7. A water pressure management plan development program executed by a computer to develop a plan for managing water pressure in a water pipe network, comprising: Based on the pipe network data, a pipe network having a predetermined diameter or more is extracted as a large-diameter pipe network; Extracting candidate skeletal pipelines that are candidates for connecting the large-diameter pipe networks; Selecting skeleton pipelines to be included in a contracted pipe network obtained by contracting the water pipe network from the skeleton pipeline candidates to generate the contracted pipe network; Extracting water pressure increase areas in the water pipe network where water pressure will increase in the future based on the pipe network data and the demand data; A water pressure management plan formulation program that determines the location to install a pressure reducing valve in a boundary pipeline connecting the inside and outside of the area of ​​increased water pressure, and formulates a pressure reducing valve installation plan for installing the pressure reducing valve in the water pipe network.

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