JPWO2017073007A1 - Water distribution operation system, water distribution operation method, and recording medium - Google Patents

Abstract

Create a pump operation plan that can reduce both power consumption of the pump and fluctuations in pump operation patterns. The water distribution operation system (200) includes an information input unit (201) that provides plan creation information used for creating a water distribution plan in a water distribution network including one or more facilities and a pipeline connecting the facilities; Based on the plan creation information, by finding a solution to an optimization problem including at least the power consumption cost of the pumps installed in one or more of the facilities and the cost of changing the operation pattern of the pumps in the facilities, A water distribution plan creation unit (202) for creating a pump operation plan including the operation pattern of the pump and the amount of water output from the pump;

Description

  The present invention relates to a water distribution operation system and the like capable of creating an appropriate water distribution plan.

  In recent years, a technique for creating a water distribution plan capable of realizing appropriate water distribution control in a large-scale water distribution network (for example, a water network) has been demanded. When creating a water distribution plan, it may be required to determine the flow rate of each pipeline or the operation plan of a water distribution control device (such as a pump) so as to reduce power consumption. Techniques related to the creation of such a water distribution plan are disclosed in the following patent documents.

  Patent Document 1 considers the relationship between the water flow rate of each pipeline and the operation cost of each pump facility, and relates to a device for creating a water supply operation plan for the purpose of minimizing the operation cost. Is disclosed. The apparatus disclosed in Patent Document 1 approximates a function representing the power consumption of a pump using a piecewise linear model, and creates a pump operation plan for reducing the power consumption.

  Patent Document 2 discloses a technique relating to a water distribution control device for the purpose of suppressing a short-term fluctuation in the number of operating pumps in a water distribution station. The apparatus disclosed in Patent Document 2 does not change the number of pumps operating at a water distribution station when the water distribution flow rate associated with demand fluctuation in a short cycle is close to the threshold flow rate at which the number of pumps operating at a certain water station increases or decreases. In the same way, the amount of drainage at other water distribution stations is controlled.

  Patent Document 3 discloses a technique relating to a water supply operation support device that calculates the number of operating pumps in consideration of fluctuations in the water level of a distribution reservoir. The device disclosed in Patent Literature 3 extracts all operation patterns of the pump, and calculates the difference between the predicted water distribution amount and the planned water supply amount, the number of pump switching times, the power consumption amount, and the power charge for each operation pattern. To do. The apparatus disclosed in Patent Document 3 narrows down the operation patterns according to items preferentially selected by the operator among all the operation patterns.

  Patent Document 4 discloses a technique related to a water distribution control system for the purpose of minimizing power consumption in the entire transmission and distribution type. The system disclosed in Patent Document 4 is a water distribution plan optimization problem that minimizes the power consumption of a pump in a water distribution station at each time, and water that minimizes the power consumption used for water transmission from a water treatment plant and a water reservoir. Set operational planning optimization problems. Based on the solutions of these optimization problems, the system sets a mathematical optimization problem that reduces power consumption in the entire transmission and distribution system, and corrects the flow rate of each drain pipe by solving the problem.

JP 2012-197629 A JP 2013-151833 A Japanese Patent Laid-Open No. 2004-244942 JP-A-2015-114804

  In the water distribution plan, it may be required to reduce the switching (change) of the operation pattern of the pump as well as reducing the power consumption. That is, there are cases where it is required to reduce the load on the pump while reducing the human cost associated with the control of the pump by reducing the switching of operation or stoppage of the pump.

  It is difficult for the techniques described in the above patent documents to sufficiently satisfy such a requirement. That is, the techniques disclosed in Patent Document 1 and Patent Document 4 are merely techniques for minimizing power consumption. In addition, the technology disclosed in Patent Document 2 is a technology for controlling the amount of drainage at each water distribution station based on the threshold value of the amount of water distribution in which the number of operating pumps increases or decreases. It is not always possible to improve. In addition, the technique disclosed in Patent Document 3 can only set the number of pump switching as an item to be preferentially considered during operation, and can be optimized including power consumption. Not exclusively. Moreover, since the technique disclosed in Patent Document 3 needs to calculate the operation pattern of all the pumps, when a pump operation plan is frequently created in a large-scale water distribution network, the calculation load is high.

  The present invention has been made in view of the above circumstances. That is, the main object of the present invention is to provide a water distribution operation system and the like capable of creating a pump operation plan that can reduce both power consumption and change in pump operation pattern.

  In order to achieve the above object, a water operation system according to an aspect of the present invention is a plan creation used for creating a water distribution plan in a water distribution network including one or more facilities and a pipeline connecting the facilities. Optimum including the information input unit that provides information, the power consumption cost of the pumps installed in one or more of the facilities, and the cost of changing the operation pattern of the pumps in the facility based on the plan creation information A water distribution plan creation unit that creates a pump operation plan including the operation pattern of the pump and the amount of water output from the pump by obtaining a solution to the conversion problem.

  Further, the water distribution operation method according to one aspect of the present invention is based on plan creation information used for creating a water distribution plan in a water distribution network including one or more facilities and a pipeline connecting the facilities. By obtaining a solution to an optimization problem including the power consumption cost of a pump installed in one or more of the facilities and the switching cost of the operation pattern of the pump in the facility, the operation pattern of the pump and the pump A pump operation plan including the output water volume from

  In addition, the same purpose is achieved by a computer program for realizing the water distribution operation system or the water distribution operation method having the above-described configuration by a computer, a computer-readable recording medium storing the computer program, and the like. Achieved.

  ADVANTAGE OF THE INVENTION According to this invention, the pump operation plan which can reduce both the power consumption of a pump and the change of the operation pattern of a pump can be created.

FIG. 1 is a block diagram (part 1) illustrating a functional configuration of a water distribution operation system 100 according to the first embodiment of the present invention. FIG. 2 is a block diagram (part 2) illustrating the functional configuration of the water distribution operation system 100 according to the first embodiment of the present invention. FIG. 3 is an explanatory diagram schematically showing a power consumption curve that models the relationship between the water flow rate and the power consumption for each operation pattern of the pump. FIG. 4 is an explanatory view schematically showing a specific example of a water distribution network. FIG. 5 is an explanatory diagram illustrating an example of an operation pattern of the pump. FIG. 6 is an explanatory diagram schematically illustrating the amount of water stored in the tank at each time interval. FIG. 7 is a flowchart showing an example of the operation of the water distribution operation system 100 according to the first embodiment of the present invention. FIG. 8 is an explanatory diagram schematically illustrating an example of a water distribution network assumed in the specific example according to the first embodiment of the present invention. FIG. 9 is an explanatory diagram illustrating data representing the amount of water demand in each time interval in the specific example according to the first embodiment of the invention. FIG. 10 is a graph showing a change in the amount of water demand in each time interval in the specific example according to the first embodiment of the present invention. FIG. 11 is an explanatory diagram illustrating pump operation pattern data in the specific example of the first embodiment of the invention. FIG. 12 is an explanatory diagram (part 1) illustrating a power consumption model for each operation pattern of the pump in the specific example according to the first embodiment of the invention. FIG. 13 is an explanatory diagram (part 2) illustrating a power consumption model for each operation pattern of the pump in the specific example according to the first embodiment of the invention. FIG. 14 is an explanatory diagram illustrating data representing a power consumption model for each operation pattern of the pump in the specific example according to the first embodiment of the invention. FIG. 15 is an explanatory diagram illustrating data representing the amount of purified water for each water purification plant in the specific example according to the first embodiment of the present invention. FIG. 16 is an explanatory diagram showing the output water amount of the pump in each time interval obtained as a solution to the optimization problem in the specific example according to the first embodiment of the present invention. FIG. 17 is an explanatory diagram (part 1) illustrating a pump operation pattern in each time interval obtained as a solution to the optimization problem in the specific example according to the first embodiment of the present invention. FIG. 18 is an explanatory diagram (No. 2) illustrating the pump operation pattern in each time interval obtained as a solution to the optimization problem in the specific example according to the first embodiment of the present invention. FIG. 19 is an explanatory diagram (part 3) illustrating the operation pattern of the pump in each time interval obtained as a solution to the optimization problem in the specific example according to the first embodiment of the present invention. FIG. 20 is an explanatory diagram showing the flow rate of the pipeline in each time interval obtained as a solution to the optimization problem in the specific example according to the first embodiment of the present invention. FIG. 21 is a block diagram illustrating a functional configuration of a water distribution operation system 200 according to the second embodiment of the present invention. FIG. 22 is a block diagram illustrating a hardware configuration of an information processing apparatus that can realize a water distribution operation system or its components in each embodiment of the present invention.

  Prior to the description of each embodiment of the present invention, technical considerations in the present invention will be described in more detail.

  As described above, when creating a water distribution plan, it may be required to determine the flow rate of each pipeline so as to reduce power consumption in the water distribution network. In this case, in the water distribution operation system, for example, a water distribution plan is created by the following method. That is, the water distribution operation system sets a mathematical optimization problem that employs power consumption in the distribution network (for example, power consumption of pumps in water purification plants and water supply stations) as an objective function. Then, the water distribution operation system creates a water distribution plan that can reduce power consumption by solving the set mathematical optimization problem.

  When the mathematical optimization problem is set as described above, the water discharge amount (discharge amount output from the pump) in each pump and the power consumption of the pump are expressed by a non-linear relationship. From this, it is technically examined how to set (formulate) a function (hereinafter referred to as “power consumption function”) that represents the relationship between power consumption and flow rate in the pump. It becomes a matter. Since the power consumption function of the pump shows a different convex function shape for each specific flow rate range, it is not always easy to model the objective function using the power consumption function.

  Further, as described above, when operating an actual water distribution plan, it may be required to reduce the number of times of switching the pump operation pattern (for example, the pump operation and stop patterns). Thus, it is a technical consideration to set an optimization problem in a format that includes the cost required for switching the operation pattern of the pump (hereinafter sometimes referred to as “switching cost”) in addition to the power consumption. . In this case, how to set (formulate) the switching cost is a technical consideration. In general, mathematical optimization is difficult when the switching cost is represented by discrete values. The water distribution operation system in each of the following embodiments enables mathematical optimization by appropriately approximating the optimization problem including discrete values as described above.

  The water distribution operation system described using each embodiment below sets a mathematical optimization problem that incorporates information related to the water distribution network (information on the network topology of the water distribution network). And the solution which reduces simultaneously the power consumption of a pump and the frequency | count of switching of the operation pattern of a pump is calculated | required by solving the optimization problem which concerns. Thus, the water distribution operation system can derive a water distribution plan for each pipeline constituting the water distribution network and a pump operation plan. Further, the optimization problem set by the water distribution operation system is reduced to sequential optimization that can execute the optimization process per time at high speed. Thus, the water distribution operation system can derive an appropriate water distribution plan for each large time distribution network every short time.

  Hereinafter, an embodiment of the present invention capable of realizing such a water distribution operation system will be specifically described. The configurations described in the following embodiments are exemplifications, and the technical scope of the present invention is not limited thereto. The water distribution operation system described below may be configured using a single device (physical or virtual device). Such a water distribution operation system may be realized using a plurality of separated devices (physical or virtual devices). In this case, the water distribution operation system is realized as a system including a plurality of devices. The plurality of devices constituting the water distribution operation system may be communicably connected via a wired network, a wireless network, or a communication network (communication line) appropriately combining them. Such a communication network may be a physical communication network or a virtual communication network.

  The water distribution operation system may be realized using a cloud system configured by using a plurality of physical or virtual information processing apparatuses and a communication network. In this case, such a water distribution operation system can be provided in the cloud system in the SaaS (Software as a Service) format.

<First Embodiment>
DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments capable of implementing the present invention will be described in detail with reference to the drawings.

<Configuration>
FIG. 1 is a block diagram illustrating a functional configuration of a water distribution operation system of the present invention. The water distribution operation system 100 includes a water distribution network information input device 101, a parameter information input device 102, and a water distribution plan creation device 103. Further, the water distribution operation system 100 may include an output device 104. These components constituting the water distribution operation system 100 are communicably connected using an appropriate communication method.

  First, the outline of the water distribution operation system 100 will be described. The water distribution operation system 100 includes a demand amount (may be a predicted value) for each time unit (time section) at each demand point included in the water distribution network, a fresh water production amount at each water treatment plant, and a water distribution network. The configuration information (described later) is acquired as an input. The water distribution operation system 100 obtains a solution to an optimization problem including at least the change cost (switching cost) required for switching (changing) the pump operation pattern and the power consumption of the pump based on the input. Thereby, the water distribution operation system creates a pump operation plan capable of reducing the pump switching cost and the power consumption. In addition, the water distribution operation system 100 creates a water distribution plan for each pipe line (a flow rate plan representing the water flow rate of the pipe) that can reduce the cost of changing the operation pattern of the pump and the power consumption of the pump. For example, the water distribution operation system 100 creates a plan for an operation pattern or a pump output (output water flow rate) for each time section (for example, 15 minutes) for a pump installed in a facility constituting the distribution network. May be. Moreover, the water distribution operation system 100 may create a water distribution plan (flow rate plan) for each certain time section (for example, 15 minutes) for each pipe constituting the water distribution network, for example.

  Next, each component which comprises the water distribution operation system 100 is demonstrated. The water distribution network information input device 101 is a device that inputs information (plan creation information) used to create a water distribution plan in the water distribution network to the water distribution plan creation device 103. Information used for creating a water distribution plan includes, for example, information (distribution network configuration information) representing the configuration of the water distribution network. Information representing the structure of the water distribution network includes, for example, the characteristics of the facilities that make up the water distribution network, such as water pipes, water supply stations, water treatment plants, branch points, and demand points, and the equipment (pumps, valves, etc.) installed in those facilities. It may include information to represent. Further, the information representing the configuration of the water distribution network may include information representing the connection relationship between the facilities constituting the water distribution network. Moreover, the information used for preparation of a water distribution plan may also contain information, such as the demand forecast in a demand point, or the amount of purified water in a water purification plant, for example. In addition, the information used for creation of a water distribution plan may be input (set) to the water distribution network information input device by a user (not shown) of the water distribution operation system 100, for example. Moreover, the distribution network information input device 101 may acquire plan creation information stored in an external information processing device (such as a server) connected via a communication network.

  Specifically, the water distribution network information input device 101 includes a network topology input unit 101a, a demand prediction unit 101b, and a purified water amount determination unit 101c, as illustrated in FIG.

  The network topology input unit 101 a provides information on the network topology of the piping network to the water distribution plan creation device 103. For example, the network topology input unit 101 a may provide the water distribution plan creation device 103 with the water distribution network configuration information described above. In addition, the network topology input unit 101a includes, for example, upper and lower limit values of the flow rate of each pipeline, upper and lower limit values of the change amount of the flow rate output from each facility, upper and lower limit values of the water storage amount, and a pump installed in each facility Various conditions relating to the water distribution network, such as the characteristics of the water distribution, are input to the water distribution plan creation device 103.

  The network topology input unit 101a also provides the water distribution plan creation device 103 with information representing the power consumption for each operation pattern of each pump in a facility such as a water purification plant or a water supply station. For example, the network topology input unit 101a models the relationship between the water flow rate in the pump and the power consumption for each operation pattern of each pump, and provides the water distribution plan creation apparatus 103 with information on the model (power consumption model). May be.

  The pump operating pattern represents, for example, a combination of pumps operating at a certain timing (or time interval). For example, assume a case where two pumps (referred to as P1 and P2) are arranged in a certain facility. If the pump operating pattern in this case is “l”, “l” is “{P1}” (only P1 is operating), “{P2}” (only P2 is operating), “{P1, P2}” (P1, P2 is active), and each pattern is expressed as “l = 1, 2, 3”. The operation pattern of the pump indicates whether the pump to which a certain pipeline is connected (flowing water through the pipeline) is P1, P2, or P1 and P2. Further, for example, if a pump including “0” in the flow rate range is P1, a state where the operation pattern is “1 = 1” and the discharge amount from the pump P1 is “0” is a state where there is no pump to be operated. To do. Note that even if the operation pattern is “l = 1” and the flow rate from the pump P1 becomes “0”, the pump connected to the pipeline remains P1, so that the switching cost does not occur. deal with.

  In the power consumption model, for example, for each operation pattern of each pump, a power consumption curve representing the relationship between the water flow rate in the pump and the power consumption is modeled using a simulator or the like, and the small power curve is approximated piecewise linearly. May be created. In this case, the network topology input unit 101a may provide the coefficient value of the piecewise linear approximation straight line to the water distribution plan creation device 103.

  Hereinafter, an outline of the creation of the power consumption model will be described. In the following, for convenience of explanation, a mode in which the network topology input unit 101a creates a power consumption model will be described, but the present embodiment is not limited to this. For example, as illustrated in FIG. 2, the model creation device 105 that is communicably connected to the water network information input device 101 creates a power consumption model, and the network topology input unit 101 a refers to the power consumption model. Also good. Further, for example, the water distribution plan creation device 103 to be described later may create a power consumption model based on pump characteristic information provided from the water distribution network information input device 101.

The network topology input unit 101a first determines a pump pressure necessary to apply a desired water pressure to the demand point. Next, the network topology input unit 101a calculates the power consumption necessary to distribute a certain water flow rate with the determined pressure by simulation while changing the combination of pumps. At this time, as an example of a model equation of each pump used in the simulation, for example, the following equation (1) may be used.

“A” and “η _Q ” in the equation (1) are obtained from the standard value of the pump and the like. By using the model equations of the above pumps, it is possible to obtain a combination of pumps that is power efficient with respect to the water flow rate by simulation. The simulation result is obtained, for example, as the power consumption curve of FIG. FIG. 3 is a diagram illustrating the relationship between the water flow rate (the amount of water output from the pump according to each operation pattern) and the power consumption for each operation pattern (pattern 1, pattern 2, and pattern 3) of the pump. A power consumption model can be obtained by piecewise linear approximation of the power consumption curve (piecewise linear approximation in FIG. 3).

  The demand prediction unit 101b provides the water distribution plan creation device 103 with a predicted value of the demand amount at a certain timing (for example, time or time interval) of each demand point. The predicted value of the demand amount may be given by, for example, a user of the water distribution operation system 100 or may be appropriately created by the demand prediction unit 101b based on the past demand record.

  The purified water amount determination unit 101c provides the water distribution plan creation device 103 with the purified water amount (for example, the amount of fresh water produced per day) created by the water purification plant. The amount of water purification concerned may be calculated | required based on the capability, driving | running condition, etc. of each water purification plant, for example, and may be given by the user of the water distribution operation system 100, etc.

  The parameter information input device 102 provides the water distribution plan creation device 103 with various parameters used for setting an optimization problem (described later) in the water distribution plan creation device 103 (particularly, the optimization problem setting unit 103a). The parameter information input device 102 includes a weight parameter setting unit 102a, an approximate parameter setting unit 102b, and a convergence determination parameter setting unit 102c.

  The weight parameter setting unit 102a provides the water distribution plan creation device 103 with parameters (weight parameters) for determining the importance of power consumption and switching cost in the objective function included in the optimization problem. The approximate parameter setting unit 102b provides a parameter (approximate parameter) for controlling the approximation accuracy when approximating the set optimization problem to the water distribution plan creating apparatus 103. The convergence determination parameter setting unit 102 c provides a parameter (convergence determination parameter) related to the end condition in the optimization process of the optimization problem to the water distribution plan creation device 103. Specific examples of the above parameters will be described later.

  The water distribution plan creation device 103 sets an optimization problem that can reduce the operation cost of the water distribution network including at least switching of the operation pattern of the pump and power consumption of the pump, and obtains a solution to the optimization problem. The water distribution plan creation device 103 creates a water distribution plan using the obtained solution. The water distribution plan creation device 103 includes an optimization problem setting unit 103a and an optimization processing unit 103b. The optimization problem setting unit 103a sets an optimization problem that can reduce both the operation pattern switching of the pump and the power consumption of the pump. Specifically, the optimization problem setting unit 103a sets the objective function of the optimization problem and the constraint conditions. The optimization processing unit 103b obtains a solution to the optimization problem set by the optimization problem setting unit 103a. The optimization processing unit 103b approximates the optimization problem using an appropriate method, and obtains a solution by executing mathematical optimization processing.

  First, the optimization problem set by the optimization problem setting unit 103a will be described.

  In the following description, as illustrated in FIG. 4, a water distribution network including one or more water purification plants, one or more water stations, one or more branch points, and one or more demand points is assumed. A water purification plant is, for example, a facility that produces purified water from water taken from a water intake facility. The water treatment plant has water storage facilities (tanks, reservoirs, etc.) and a pump. A water supply station is a facility that distributes water sent from a water purification plant or the like to a specific area, for example. A water storage facility (tank, reservoir, etc.) and a pump are installed at the water supply station. The demand point is a facility of a consumer (for example, an office, a home, a factory, a store) that uses the distributed water. A branch point is a facility that branches pipes. Each component (facility) of the water distribution network is connected by a pipe (pipe). FIG. 4 is a diagram showing one specific example for explanation, and the present embodiment is not limited to the configuration illustrated in FIG. 4.

  In this embodiment, the water distribution network is expressed using a directed graph. Each facility in the distribution network corresponds to a node in the directed graph, and the piping corresponds to an edge (link) in the directed graph. In addition, when the piping between a certain facility X and another facility Y can flow water in either direction, the piping is represented as a separate unidirectional link for each direction.

Assume that a set of nodes of facilities (assuming “n” places) constituting the water distribution network is V (V = {1, 2,..., N}). A water treatment plant node set is represented as “F”, a water supply node set as “S”, a branch point node set as “B”, and a demand point node set as “D”. 2) is established.

Further, assuming that the water purification plant and the water supply station exist together in “K” locations, a set of these nodes is expressed as follows.

Identification information that can identify the pipeline is given to each pipeline. Specifically, for example, a number that can identify the pipeline from “1” to “m” may be assigned to each pipeline. In the time interval “t” (“t = 1,..., T”), the water flow rate “q _i (t)” flowing through the pipe number “i” is expressed by the following equation (4). The

The demand amount “d _i (t)” in the time section “t” at the demand point “d _i (i∈D)” included in the set D of demand point nodes is expressed by the following equation (5). Is done.

Next, formulation of the pump operation pattern will be described. As described above, the operation pattern of the pump represents, for example, a pump that operates at a certain timing (or time interval). When there are “L _k ” patterns as the pump operation pattern “l” in a certain facility (water purification plant F or water station S), the operation state of the pump operation pattern in the time interval “t” is expressed by the following equation (6 ).

The optimization problem setting unit 103a in the present embodiment introduces “P _{k, l} (t)” represented by the above equation (6) as a variable representing the operation state of each operation pattern of the pump. More specifically, the optimization problem setting unit 103a uses the discrete variable (for example, a binary variable representing “0” or “1”) represented by the above formula (6) to determine each operation pattern of the pump. Indicates the operating status. For example, when “P _{k, l} (t) = 1”, the operation pattern of the pump in the facility “k” (“k∈K∪S)” is “l” (that is, the operation state of the pump is the operation pattern “l”). ")". In this case, since the pump is operated according to the operation pattern “l”, the other operation patterns are “P _{k, l ′} (t) = 0, (l ≠ l ′)”. By setting the following expression (7) as a constraint condition (described later), the pump operation pattern in the facility “k” (“kεK∪S”) is determined in one way in a certain time section “t”.

This will be described using a specific example illustrated in FIG. FIG. 5 shows a pump operation pattern “l” (“l = 1”, “l = 2”, “l = 3” three patterns) in a certain facility for each time interval (“t”, “t + 1”, It is a specific example showing a change (switching) of “t + 2”). In the specific example shown in FIG. 5, the pump operation pattern “l (= 2)” in the time interval “t” is “P _{k, 1} (t) = 0”, “P _{k, 3} (t) = 0”. , “P _{k, 2} (t) = 1”. Similarly, the pump operation pattern “l (= 2)” in the time interval “t + 1” is “P _{k, 1} (t + 1) = 0”, “P _{k, 3} (t + 1) = 0”, “P _{k, 2} (t + 1) = 1 ″. The operation pattern “l (= 3)” of the pump in the time interval “t + 2” is “P _{k, 1} (t + 2) = 0”, “P _{k, 2} (t + 2) = 0”, “P _{k, 3} (T + 2) = 1 ″.

  The water distribution plan creation device 103 (in particular, the optimization problem setting unit 103a) in the present embodiment incorporates the pump operation pattern formulated as described above into the objective function in the optimization problem. By obtaining a solution to the optimization problem, the water distribution plan creation device 103 can create a pump operation plan that reduces changes in the pump operation pattern.

The optimization problem setting unit 103a calculates the output water amount from the water purification plant or water supply station (facility “k” (“k∈K∪S)”) whose pump operation pattern is “l” in the time interval “t”. And represented by the following formula (8).

As described above, in a certain time interval “t”, the operation pattern of the pump in the facility “k” (“k∈K∪S”) is determined in one way, and the restrictions on the pumping area (described later) are taken into consideration. Then, the following equation (9) is established for a certain operation pattern “l ′ (l ′ ≠ l)”. That is, when the pump is operating with the operation pattern “l ′” in the facility “k”, the output with the other pattern “l” is not generated.

  The optimization problem setting unit 103a models the cost in the water distribution network using the above equations. That is, the optimization problem setting unit 103a models the cost in the water distribution network using a model that represents the switching cost of the pump, a model that represents the power consumption cost of the pump, and a model that represents the cost of the water distribution network. . More specifically, the optimization problem setting unit 103a formulates a function representing the cost for each of the three models.

The optimization problem setting unit 103a represents the pump switching cost using, for example, a model representing the operation state of the pump operation pattern in each facility. More specifically, the optimization problem setting unit 103a uses a variable (in this case, a binary variable) that represents the operation state of the pump operation pattern to determine the pump switching cost as shown in the following equation (10). Turn into. In the following, the following expression (10) may be described as a first cost model or a first cost function.

In the above formula (10), “|| x || ₀ ” represents the “L ₀ ” (elzero) norm of “x”. Specifically, "|| x || _0" represents the number of satisfying the _{"x i ≠ 0""x} i". The “L ₀ ” norm represents whether or not the operation pattern of the pump has been changed between a certain time interval (timing) and another time interval (timing). Expression (10) represents that when the time interval changes from “t” to “t + 1”, the number of operation patterns of the pump that have changed is aggregated for all time intervals and all operation patterns. For example, in the facility “k”, when the time interval is changed from “t” to “t + 1”, if the operation pattern of the pump is not changed, “L ₀ ” norm in the equation (10) becomes “0”. . For example, in the facility “k”, when the time interval changes from “t” to “t + 1”, if the pump operation pattern is changed, “L ₀ ” norm in equation (10) is non- “0”. Become. In other words, the optimization problem setting unit 103a measures the difference (change) in the operation pattern for each time interval using the “L ₀ ” norm and adopts the value as the pump switching cost. If the switching cost of the pump expressed as described above can be reduced, the number of changes in the pump operation pattern is reduced.

The optimization problem setting unit 103a represents, for example, the power consumption cost of the pump using the power consumption model described above (a model obtained by piecewise linear approximation of the power consumption curve). More specifically, the optimization problem setting unit 103a formulates the power consumption cost of the pump as follows. In the following, the following expression (11) may be described as a second cost model or a second cost function.

In the above equation (11), “α _k2,1 ” and “β _k2,1 ” are coefficients of a piecewise linear model representing the relationship between the water flow rate and the power consumption for each pump operation pattern. These coefficients may be provided from the water distribution network information input device 101 as described above.

Further, the optimization problem setting unit 103a formulates, for example, the water distribution network cost as follows. In the following, the following expression (12) may be described as a third cost model or a third cost function.

The above equation (12), for coming out of a certain property k ₃ Zenkanro, indicating that aggregate the water flow flowing through the pipe for the entire time interval. The cost of the water distribution network is introduced to prevent the water distribution route from reaching the demand point from being detoured. By reducing the cost of the water distribution network, the water distribution route to the point of demand is relatively short.

The optimization problem setting unit 103a formulates the objective function in the optimization problem as shown in the following expression using each of the formulated cost functions. The following formula (13) can be considered to represent the total cost including each cost formulated above.

  The parameters “A” and “B” in the objective function are parameters given by the parameter information input device 102 (in particular, the weight parameter setting unit 102a).

  Next, the optimization problem setting unit 103a sets a constraint condition in the optimization problem. Hereinafter, such constraint conditions will be described.

First, the optimization problem setting unit 103a sets a flow conservation rule at a demand point as a constraint condition. The flow conservation law at the demand point is expressed by the following equation.

  The flow conservation law at the demand point indicates that the sum of the water flow rate of water entering and the sum of the water flow rates of water flow out or used match at a certain demand point. More specifically, the sum of the flow rate of water discharged from the demand point and the demand amount (use amount) at the demand point corresponds to the flow rate of water entering a certain demand point.

In addition, the optimization problem setting unit 103a sets a flow conservation rule at a branch point as a constraint condition. The flow conservation law at the branch point is expressed by the following equation.

  The flow conservation law at the branch point indicates that, at a certain branch point, the sum total of the water flow rate into which the water enters and the sum total of the water flow rate at which the water flows out match.

In addition, the optimization problem setting unit 103a sets a pumpable area as a constraint condition. The water dischargeable area of the pump is expressed by the following formula.

In the above equation (16), “Q _{k, l} ^L ” represents the lower limit of the pump water intake when the pump operation pattern at the facility “k” is “l”. “Q _{k, l} ^U ” represents the upper limit of the pump water intake amount when the pump operation pattern at the facility “k” is “l”. “Q _{k, l} ^L ” and “Q _{k, l} ^U ” may be provided from the distribution network information input device 101 (network topology input unit 101a). Alternatively, the optimization problem setting unit 103a determines “Q _{k, l} ^L ” and “Q _{k, l} ^U ” based on the pump characteristics provided from the distribution network information input device 101 and the pump operation patterns in each facility. "May be calculated.

In addition, the optimization problem setting unit 103a sets the following constraints on the pump as constraint conditions.

Expressions (17) and (18) are constraint conditions indicating that the operation pattern of the pump in a certain facility “k” is determined in a certain manner in a certain time section “t”. That is, when the time interval “t” and the facility “k” are fixed, the operation pattern of the pump is determined in one way (for example, “P _{k, 1} (t) = 1”). It can also be considered as a constraint that secures the establishment of equation (9).

  Expression (19) is a constraint representing that the amount of water output from the pump at a certain facility “k” matches the water flow rate of the pipe that discharges from the facility.

Further, the optimization problem setting unit 103a sets the flow rate restriction of each pipeline as a restriction condition. The flow restriction of each pipe line is expressed by the following equation.

The flow rate restriction of each pipeline represented by the equation (17) represents an upper limit value and a lower limit value of the water flow rate that can flow through each pipeline. Since there are cases where the direction of the flow of water flowing through each pipe line is limited depending on the time zone, the upper and lower limit values (“L _i (t)”, “U _i (t)” “Is expressed in a format depending on time“ t ”.

In addition, the optimization problem setting unit 103a sets a change restriction on the total water flow output from each facility (that is, a change restriction on the water flow output from a pump installed in a certain facility) as a restriction condition. The flow rate change constraint is expressed by the following equation.

In addition, the optimization problem setting unit 103a sets the water discharge restriction from the water purification plant as a restriction condition. The water discharge restriction from the water treatment plant is expressed by the following equation.

“G _k ” in Expression (22) represents the amount of purified water produced in a certain period (for example, one day) in the water purification plant “k”. Such “G _k ” is set by the water distribution network information input device 101 based on, for example, the optimal amount of water purified per day at the water purification plant. The water discharge restriction from the water purification plant expressed by the equation (22) indicates that the sum of the amount of water purified at the water purification plant and the water flow rate flowing into the water purification plant matches the water flow rate flowing out from the water purification plant.

Moreover, the optimization problem setting part 103a sets the water storage restrictions of the tank in a water purification plant and a water supply station to a constraint condition. The tank water storage constraint is expressed by the following equation.

Storage volume _"Vo k (t)" of the tank at a certain time interval "t", the initial water storage tank with _{( "Vo k (0)"} ), until the time interval t, the water flow rate which has flowed into the tank And the sum of the differences from the water flow rate flowing out of the tank. For example, if you 96 dividing one day at 15-minute intervals, water volume in at a certain time interval _{"t""Vo k (t} )" it is conceptually represented as shown in FIG. Water restrictions tank represented by the formula (23), in each time interval "t", water storage tank facilities "k" is a specific lower limit value ( _"Vo ^k L") and the upper limit value ( "Vo _k ^U ″).

  Hereinafter, for convenience of explanation, an optimization problem including the objective function and each constraint condition (Expression (14) to Expression (23)) set by the optimization problem setting unit 103a as described above is referred to as an “original problem”. There is a case. In addition, each constraint condition (Expression (14) to Expression (23)) may be described as “original constraint” or “original constraint condition”. The original problem set by the optimization problem setting unit 103a as described above is a mixed integer programming problem.

The optimization processing unit 103b continuously relaxes the original problem set as described above, and adds a penalty function to the objective function (Formula (13)). The objective function with the added penalty function is expressed as follows. The coefficient “M” of the penalty function in the following equation (24) is set by the approximate parameter setting unit 102b.

Further, the constraint condition is a constraint condition obtained by relaxing the original constraint condition as follows. Hereinafter, all relaxed constraint conditions may be referred to as “relaxation constraint conditions”.

Further, the optimization processing unit 103b calculates the “L ₀ ” norm (discrete variable) of the switching cost (one item of the equations (10) and (13)) of the pump taking discrete values as shown in the following equation: Approximate by continuous function. The coefficient “α” in the following equation (26) is set by the approximate parameter setting unit 102b.

When the above approximation is applied to the equation (10), the following equation is obtained.

Summarizing the above, the optimization processing unit 103b mathematically calculates an optimization problem expressed by the following equation, which is approximated by continuously relaxing the original problem (hereinafter sometimes referred to as “approximate optimization problem”). Perform optimization processing.

The first half of the objective function represented by the above equation (28) (the following equation (29)) is a convex function.

The latter half of the objective function represented by the above equation (28) (the following equation (30)) is also a convex function.

  From the above, the approximated optimization problem expressed by the above equation (25) is expressed in the form of a DC planning (Difference of Convex Functions Programming) problem that is a problem of minimizing the difference between two convex functions. .

  The optimization processing unit 103b may solve the approximated optimization problem using, for example, DCA (Difference of Convex functions Algorithm) described in Reference Document 1 below. In this case, the solution of the approximated optimization problem ultimately results in iterative solving of the linear programming problem. That is, the approximated optimization problem is reduced to sequential optimization in which optimization per one time can be performed at high speed. Thus, the optimization processing unit 103b can derive an optimal solution for each short time interval even when the distribution network is large.

  Even if the optimization processing unit 103b finishes the iterative process when the difference between the solution obtained in one iteration and the solution obtained in the next iteration is lower than the threshold in the process of solving the linear programming problem, Good. Note that the difference between the solutions may be expressed using, for example, the Euclidean distance between the two solutions. The end condition of the above iterative process (for example, the threshold of the difference between two solutions) is set by the convergence determination parameter setting unit 102c. The optimization processing unit 103b may employ a solution other than the following reference as a solution of the DC planning problem. Since a well-known technique can be adopted as a specific method for solving the DC planning problem, a detailed description thereof will be omitted.

[Reference 1]
Pham Dinh, T .; and Le Thi, H .; A. “Recent advance in DC programming and DCA.”, Transactions on Computational Collective Intelligence, 2014, 8342, p. p. 1-37.
Through the processing described above, the optimization processing unit 103b can obtain a solution including the following contents as a solution of the approximated optimal problem. That is, the solution to the optimization problem includes the pump operation pattern in each facility and the pump output (output water amount) in the operation pattern for each time interval (for example, every 15 minutes). In addition, the solution of the optimization problem includes the water flow rate in each pipeline in each time interval.

  The output device 104 outputs the following content from the optimal solution obtained in the water distribution plan creation device 103. That is, the output device 104 outputs a water distribution plan for each time section (a flow plan for each time section) in each pipeline. Further, the output device 104 outputs a pump operation plan (pump operation pattern and output water amount for each time section) in each facility. The output device 104 may display these on a display screen such as a display device (not shown), or may transmit the data to an operation facility of a water distribution network as electronic data in an appropriate format.

  Based on the water distribution plan output from the output device 104 and the operation plan of the pump, the operator of each facility appropriately adjusts the equipment installed in each facility, such as adjustment of valve opening / closing amount and operation control of the pump. You may operate. In addition, when each facility can be remotely operated, equipment installed in each facility may be remotely operated based on each plan. Thereby, based on the water distribution plan calculated | required by the water distribution plan preparation apparatus 103, and a pump operation plan, a water distribution network is operated appropriately.

  In addition, in this embodiment, the component which comprises the water distribution operation system 100 demonstrated above may be implement | achieved using one or more independent physical or virtual apparatuses. Moreover, one or more components among these components constituting the water distribution operation system 100 may be realized by using one common physical or virtual device. For example, the water distribution network information input device 101 and the parameter information input device 102 may be collectively realized as one physical or virtual information input device.

<Operation>
Next, operation | movement of the water distribution operation system 100 in this embodiment comprised as mentioned above is demonstrated with reference to the flowchart illustrated in FIG.

  First, the water distribution network information input device 101 provides information related to the water distribution network to the water distribution plan creation device 103 (step S701). As described above, the information related to the water distribution network includes, for example, information representing the configuration of the water distribution network. Information representing the configuration of the water distribution network includes, for example, information representing the characteristics of facilities such as water distribution pipes, water supply stations, water purification plants, branch points, demand points, and equipment (pumps, valves, etc.) installed in the facilities. Moreover, the information showing the structure of a water distribution network contains the information showing the connection relation between the facilities which comprise a water distribution network. Moreover, the information used for preparation of a water distribution plan contains information, such as the demand forecast in a demand point, or the amount of purified water in a water purification plant, for example.

  Next, the parameter information input device 102 provides various parameters used for setting the optimization problem to the water distribution plan creation device 103 (step S702).

  The water distribution plan creation device 103 (in particular, the optimization problem setting unit 103a) is an optimization problem that reduces power consumption and switching cost based on inputs from the water distribution network information input device 101 and the parameter information input device 102. Is set (step S703).

  Next, the optimization problem setting unit 103a sets an optimization problem approximated by continuously relaxing the optimization problem set in step S703 (S704). Specifically, for example, the optimization problem setting unit 103a approximates the optimization problem set in step S703 in the form of a Difference of Convex functions Programming (DC planning problem).

  The water distribution plan creation device 103 (in particular, the optimization processing unit 103b) optimizes the optimization problem approximated in step S704 (S705). Specifically, the optimization processing unit 103b may obtain a solution to the optimal problem by using the DCA disclosed in the above-mentioned reference 1. The optimization processing unit 103b can obtain an optimal solution by repeatedly solving the linear programming problem until the termination condition provided in step S702 is satisfied.

  The output device 104 outputs the optimal solution obtained in step S705 (S706).

  The water distribution operation system 100 according to the present embodiment configured as described above can derive a pump operation plan that can reduce both the power consumption of the pump and the number of times the pump operation pattern is switched. In addition, the water distribution operation system 100 according to the present embodiment can also derive a pump water consumption, the number of times the pump operation pattern is switched, and a pipe water distribution plan (flow rate plan) that can be reduced. This is because the water distribution operation system 100 sets an optimization problem (mathematical optimization problem) including the power consumption cost of the pump and the switching cost related to the switching of the operation pattern of the pump as a target to be minimized. This is because the solution is obtained using a mathematical optimization method. That is, the water distribution operation system 100 sets the mathematical optimization problem including the power consumption cost of the pump and the cost of changing the operation pattern of the pump, and optimizes (minimizes) them using the mathematical optimization method. This is because a solution is required.

  Specifically, the water distribution operation system 100 formulates a switching cost related to switching of the operation pattern by introducing a model (variable) representing an operation state of each operation pattern of the pump. The water distribution operation system 100 formulates the water distribution optimization problem as a mixed integer programming problem including the switching cost and the power consumption of the pump as objective functions. And the water distribution operation system 100 performs the optimization process regarding the said optimization problem by performing a specific approximation process.

  The solution resulting from the optimization process is optimized to minimize pump switching costs. That is, since the switching function is included in the objective function to be minimized, in the optimum solution obtained as a result of the optimization process, the number of switching of the pump operation pattern is small. Thus, the water distribution operation system 100 can create a pump operation plan that can reduce the number of times the pump operation pattern is switched. When the pump is operated based on such a pump operation plan, the pump operation pattern does not need to be frequently switched in a short time, so that the operation cost (human cost) is reduced. Further, it is possible to reduce the load generated on the pump as the pump is operated and stopped.

  Further, as described above, the optimization problem set by the water distribution operation system 100 (particularly, the water distribution plan creation device 103) results in iterative optimization of the linear programming problem that can execute the optimization process once. Is done. As a result, even when the distribution network is large, it is possible to derive the optimum solution at high speed. Therefore, it is possible to derive a water distribution plan and a pump operation plan every short time for a large-scale distribution network.

  From the above, according to the water distribution operation system 100 in the present embodiment, it is possible to create a pump operation plan that can reduce both the power consumption of the pump and the change of the operation pattern of the pump.

<Specific example>
Hereinafter, the specific example at the time of applying the water distribution operation system 100 in this embodiment to the specific water distribution network illustrated in FIG. 8 is demonstrated. The specific example illustrated in FIG. 8 is an example for explanation, and the present embodiment is not limited to this.

  First, for each facility illustrated in FIG. 8, for example, an identification number is assigned as follows. That is, “{water purification plant F1, water purification plant F2, water supply plant S1, branch point B1, demand point D1, demand point D2} = {1, 2, 3, 4, 5, 6}”. In this case, the set of facilities is represented as “V = {1, 2, 3, 4, 5, 6}”. Moreover, the number which can identify each piping is provided to piping which connects each facility so that it may illustrate in FIG. In this case, a set of pipes is represented as “E = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12}”. For example, the water distribution network information input device 101 (network topology input unit 101a) provides the water distribution plan creation device 103 with data representing the connection status of each facility and pipe.

  In the specific example shown in FIG. 8, it is assumed that the data illustrated in FIG. 9 is given as data representing the time change of the demand amount at the demand point D1 and the demand point D2. FIG. 10 is a graph of FIG. In addition, the time change of the said demand amount may be the predicted value derived | led-out based on various conditions (a weather condition, a seasonal variation condition, a day of the week, a time zone), the past track record value, etc., for example. The time change of the demand amount is set in the water distribution plan creation device 103 by the water distribution network information input device 101 (demand prediction unit 101b). In the specific examples shown in FIGS. 9 and 10, the time interval is, for example, 15 minutes. The data representing the change in demand over time may include, for example, data for one day (96 sections at 15-minute intervals). For example, an appropriate value other than 15 minutes may be set as the time interval value. The data representing the change in demand over time may include, for example, data for an appropriate period other than one day.

  An example of the operation pattern of the pumps arranged in the water purification plant F1, the water purification plant F2, and the water supply station S1 in the specific example shown in FIG. 8 is illustrated in FIG. As illustrated in FIG. 11, two pumps (pump A and pump B) are installed in the water purification plant F1 and the water purification plant F2, and one pump (pump C) is installed in the water supply station. Is assumed. For example, the pump A and the pump C may be small pumps, and the pump B may be a large pump (rather than the pumps A and C). In the specific example shown in FIG. 11, “Pattern 1” in the water purification plant F1 represents a pattern in which only the pump A operates, and “Operation pattern 2” represents a pattern in which only the pump B operates. The same applies to water purification plant F2. “Pattern 1” in the water supply station S1 represents a pattern in which only the pump C operates. In addition, the specific example shown in FIG. 11 is only one example, and the number of pumps installed in each facility and the operation pattern (combination of operating pumps) may be set as appropriate.

  The water distribution network information input device 101 (network topology input unit 101a) includes, for example, the configuration of the pump of each facility as illustrated in FIG. 11 and its operation pattern as a part of information representing the facility in each facility. The data is provided to the water distribution plan creation device 103.

  In this specific example, the power consumption model representing the relationship between the water flow rate and the power consumption for each operation pattern of each pump is a straight line that is piecewise linearly approximated as illustrated in FIGS. 12 and 13. Assume that it is given. FIG. 12 represents a power consumption model for each operation pattern of each pump in the water purification plant F1 and the water purification plant F2. FIG. 13 shows a power consumption model for each operation pattern of each pump in the water supply station S1. The water distribution network information input device 101 (network topology input unit 101a) may provide data representing the power consumption model (for example, FIG. 14) to the water distribution plan creation device 103. Note that the network topology input unit 101a may provide the water distribution plan creation apparatus 103 with a coefficient representing the power consumption model (for example, the slope and intercept of the piecewise linear line). The network topology input unit 101a creates, for example, a power consumption model for each facility by executing a simulation based on the characteristics of each pump (such as pump specifications) and the pump operation pattern. Also good.

  Moreover, in the specific example illustrated in FIG. 8, it is assumed that the amount of purified water per day of the water purification plant F1 is given as data shown in FIG. In this specific example, the water distribution network information input device 101 (water purification amount determination unit 101c) provides the water distribution plan creation device 103 with a water purification amount for each water purification plant as exemplified in FIG. In addition, the purified water amount determination part 101c may create the data of the purified water amount based on demand prediction etc., for example.

Regarding the specific example illustrated in FIG. 8, the water distribution plan creation device 103 formulates, for example, the pump switching cost as follows.

Moreover, the water distribution plan preparation apparatus 103 formulates the power consumption cost of a pump as follows, for example.

Moreover, the water distribution plan preparation apparatus 103 formulates a water distribution network cost cost as follows, for example.

In the above equation, “q _i (t)” represents the flow rate of water flowing through the pipe number “i”.

In this specific example, the following values are set for the original constraint conditions. First, the following values are set for the constraint condition (formula (16)) of the pumpable area.

Further, the following values are set for the flow rate restriction (Equation (20)) of each pipeline. In this specific example, a common value is set for each pipeline (1 to 12).

Moreover, the following values are set for the restriction (formula (21)) on the flow rate change.

Further, the following values are set for the tank water storage constraint (Formula (23)).

  Each of the constraint conditions may be set based on data provided from the water distribution network information input device 101, or may be set in advance in the water distribution plan creation device 103.

The water distribution plan creation device 103 sets the objective function of the approximated optimization problem corresponding to the above equation (28) as the following equation.

  “A”, “B”, “M”, and “α” in the above equation are provided from the parameter information input device 102 to the water distribution plan creation device 103, respectively.

The water distribution plan creation device 103 (optimization processing unit 103b) solves the set optimization problem using, for example, the method described in Reference Document 1. From the solution of the optimization problem, as illustrated in FIG. 16, the output (output water amount) of the pump in each facility (water purification plant F1, water purification plant F2, and water supply station S1) for each time interval (for example, every 15 minutes). Is obtained. Note that the solution to the above optimization problem includes the output of all the operation patterns of the pumps of each facility for each time interval, but each facility has only one operation pattern of pumps operating in a specific time interval. Determined. Therefore, FIG. 16 represents the output water amount by the operation pattern of the pump which is operating in each time interval. When FIG. 10 is compared with FIG. 16, the output water amount of the pump from the water purification plant F2 and the water supply station S1 decreases as the demand at the demand point D1 and the demand point D2 decreases. In the time interval “1” to “4”, it is larger than “8” ([m ³ / (15 min)], hereinafter omitted units) which is the upper limit of the flow rate of the operation pattern (“pattern 1”) in the water purification plants F1 and F2. Demand is occurring. In this case, since the water supply station discharges water from the tank, the amount of water discharged from the water purification plant F1 is less than or equal to “8” (the upper limit of “Pattern 1”). In the time sections “6” and “7”, a demand of “9” is generated that exceeds the upper limit of the flow rate of the operation pattern (“Pattern 1”) in the water purification plants F1 and F2. However, also in this case, the operation pattern of the water purification plants F1 and F2 is maintained as “pattern 1” by discharging water from the tank of the water supply station. As described above, although there are many time intervals in which the demand is larger than the upper limit (“8”) of the flow rate of the operation pattern (“Pattern 1”) in the water purification plants F1 and F2, as a result, the number of pump switchings in all time intervals is Only once. This is because not only the power consumption but also the switching cost is explicitly included in the objective function to minimize the objective function.

  Moreover, from the solution of the optimization problem, as illustrated in FIGS. 17 to 19, the operation pattern of the pump in each facility (water purification plant F1, water purification plant F2, and water supply station S1) is obtained. From FIG. 10 and FIGS. 16 to 19, during the time interval “t = 1” to “t = 10”, the operation pattern of the pumps in the water purification plant F1 and the water supply station S1 remains “pattern 1”. Therefore, even when the demand amount changes (decreases in this specific example), it is not necessary to change the operation pattern of the pump in these facilities. For the water purification plant F2, the pump operation pattern fluctuates only once at the timing when the demand falls below "8" which is the upper limit of the flow rate of "Pattern 1" at the water purification plants F1 and F2 (time interval "t = 5"). To do. However, even if the demand at the demand point D2 increases in the time intervals “t = 6” and “t = 7”, the operation pattern of the pump does not change. That is, it is considered that the water distribution plan creation device 103 in the present embodiment can reduce fluctuations in the pump operation pattern in each facility. Moreover, from FIG. 16, about the water purification plant F1 which is not directly connected to a demand point, the output water amount of a pump is not linked with the fluctuation | variation of a demand amount, and is smooth. That is, about the water purification plant F1, since the output water amount of the pump is smoothed, it is possible to reduce the power consumption of the pump. That is, it is considered that the water distribution plan creation device 103 in this embodiment can reduce the power consumption of the pump in each facility.

Furthermore, as illustrated in FIG. 20, the water flow rate (flow rate plan) in each pipeline for each time interval is obtained from the solution of the optimization problem. Each graph shown in FIG. 20 represents a change over time in the water flow rate of a pipe that flows out from each facility. More specifically, each graph illustrated in FIG. 20 represents a change over time in the water flow rate of a pipeline that flows out of the facility for each facility that is the starting point of each pipeline. That is, the graph of (A) of FIG. 20 represents the time change of the water flow rate of the pipe line discharged from the water purification plant F1. Moreover, the graph of (B) of FIG. 20 represents the time change of the water flow rate of the pipe line which discharges from the water purification plant F2. Moreover, the graph of (C) of FIG. 20 represents the time change of the water flow rate of the pipe line which discharges from water supply station S1. Moreover, the graph of (D) of FIG. 20 represents the time change of the water flow rate of the pipe line which flows out from the branch point B1. Moreover, the graph of (E) of FIG. 20 represents the time change of the water flow rate of the pipe line which flows out from the demand point D1. Moreover, the graph of (F) of FIG. 20 represents the time change of the water flow rate of the pipe line which flows out from the demand point D2. The horizontal axis of each graph shown in FIG. 20 represents the time interval (1 interval = 15 [min]), and the vertical axis represents the water flow rate (unit: [m ³ / (15 min)]) output from each facility. Represent. From the constraint condition of Expression (19), the total water flow amount flowing out from each facility coincides with the output water amount of the pump.

  In this specific example, the water distribution plan creation device 103 can create a pump operation plan that has, for example, the pump output and operation pattern illustrated in FIGS. 16 to 19. Moreover, the water distribution plan preparation apparatus 103 can create the flow rate plan of each pipeline based on the optimal water flow rate of each pipeline illustrated in FIG. 20, for example.

  Based on the water distribution plan and the operation plan of the pump, the operator of each facility may appropriately operate the equipment installed in each facility, for example, adjusting the opening / closing amount of the valve and controlling the operation of the pump. Accordingly, the water distribution network is appropriately operated based on the water distribution plan (flow rate plan) obtained by the water distribution plan creation device 103 and the pump operation plan.

<Second Embodiment>
Next, a second embodiment that is a basic embodiment of the present invention will be described. FIG. 21 is a block diagram illustrating a functional configuration of the water distribution operation system 200 in the present embodiment. As illustrated in FIG. 21, the water distribution operation system 200 in the present embodiment includes an information input unit (information input unit) 201 and a water distribution plan creation unit (water distribution plan creation unit) 202. These components constituting the water distribution operation system 100 are communicably connected using an appropriate communication method.

  In this embodiment, the component which comprises the water distribution operation system 200 may be implement | achieved using one or more independent physical or virtual apparatuses. In addition, among these constituent elements constituting the water distribution operation system 200, one or more constituent elements may be realized using one common physical or virtual device.

  The information input unit 201 provides plan creation information used for creating a water distribution plan in a water distribution network including one or more facilities and a pipeline connecting the facilities.

  The plan creation information may be the same as the plan creation information provided to the water distribution plan creation device 103 by the water distribution network information input device 101 in the first embodiment, for example.

  Further, the plan creation information may include, for example, various parameters used in formulation of an optimization problem described later or a solution thereof. Such parameters may be the same as the parameters (weight parameters, approximation parameters, convergence determination parameters) provided by the parameter information input device 102 to the water distribution plan creation device 103 in the first embodiment, for example.

  The information input unit 201 may have the same configuration as the water network information input device 101 and the parameter information input device 102 in the first embodiment, for example. The information input unit 201 may have the same functions as the water network information input device 101 and the parameter information input device 102 in the first embodiment, for example.

  Based on the plan information provided from the information input unit 201, the water distribution plan creation unit 202 switches the power consumption cost of the pumps installed in at least one of the facilities and the operation pattern of the pumps in the facility. (Change) Find solutions to optimization problems including costs. And the water distribution plan preparation part 202 produces the pump operation plan containing the operation pattern of the said pump, and the output water amount from the said pump using the calculated | required solution.

  The optimization problem may be a mathematical optimization problem similar to the optimization problem described in the first embodiment, for example. Moreover, the water distribution plan preparation part 202 may solve the said optimization problem using the solution similar to the said 1st Embodiment.

  In addition, the water distribution plan preparation part 202 may be provided with the structure similar to the water distribution plan preparation apparatus 103 in the said 1st Embodiment, for example. Moreover, the information input part 201 may be provided with the function similar to the water distribution plan preparation apparatus 103 in the said 1st Embodiment, for example.

  The water distribution operation system 200 (water distribution plan creation unit 202) in the present embodiment configured as described above sets an optimization problem that reduces both the power consumption cost of the pump and the cost of changing the operation pattern of the pump. By solving the optimization problem, the water distribution operation system 200 can derive a pump operation plan in which not only the power consumption cost but also the change cost of the pump operation pattern is optimized (minimized). That is, the water distribution operation system 200 sets the mathematical optimization problem including the power consumption cost of the pump and the cost of changing the operation pattern of the pump, and optimizes (minimizes) them using the mathematical optimization method. ) To find a solution.

  As mentioned above, according to the water distribution operation system 200 in this embodiment, the pump operation plan which can reduce the power consumption of a pump and the fluctuation | variation of the operation pattern of a pump can be created.

<Configuration of hardware and software program (computer program)>
Hereinafter, a hardware configuration capable of realizing each of the above-described embodiments will be described.

  In the following description, the water distribution operation systems (100, 200) described in the above embodiments are collectively referred to as “water distribution operation system”. Each component included in the water distribution operation system is simply referred to as “component of the water distribution operation system”.

  The water distribution operation system described in the above embodiments may be configured by one or a plurality of dedicated hardware devices. In that case, each component shown in each of the above figures (FIGS. 1, 2, and 21) uses hardware (an integrated circuit or a storage device on which processing logic is mounted) that is partially or fully integrated. It may be realized.

  When the water distribution operation system is realized by dedicated hardware, the constituent elements of the water distribution operation system may be realized by, for example, an electric circuit capable of providing each function. Such an electric circuit may be constituted by a single device or a plurality of devices. The electric circuit may be mounted using an integrated circuit such as SoC (System on a Chip). In addition, the electric circuit may be a chip set mounted using one or more integrated circuits. In this case, the data held by the components of the water distribution operation system is, for example, a RAM (Random Access Memory) area integrated as an integrated circuit, a flash memory area, or a storage device (semiconductor storage device) connected to the integrated circuit Etc.). Such data includes, for example, information on the water distribution network provided by the water distribution network information input device 101, information on the parameters provided by the parameter information input device 102, plan information provided by the information input unit 201, and the like.

  In addition, when the water distribution operation system is realized by dedicated hardware, a communication line connecting each component of the water distribution operation system may be a known communication bus. Also, the communication line connecting each component is not limited to bus connection, and each component may be connected by peer-to-peer. When the water distribution operation system is configured by a plurality of hardware devices, the respective hardware devices may be communicably connected by appropriate communication means (wired, wireless, or a combination thereof).

  The above-described water distribution operation system or its components may be configured by general-purpose hardware as exemplified in FIG. 22 and various software programs (computer programs) executed by the hardware. In this case, the water distribution operation system may be configured by one or more appropriate numbers of general-purpose hardware devices and software programs. That is, an individual hardware device may be assigned to each component configuring the water distribution operation system, and a plurality of components may be realized using one hardware device.

  The arithmetic device 1 in FIG. 22 is an arithmetic processing device such as a general-purpose CPU (Central Processing Unit) or a microprocessor. The arithmetic device 1 reads various software programs stored in, for example, a non-volatile storage device 3 to be described later to the storage device 2 and executes processing according to the software programs. For example, the constituent elements of the water distribution operation system in each of the above embodiments may be realized as a software program executed by the arithmetic device 1.

  The storage device 2 is a memory device such as a RAM that can be referred to from the arithmetic device 1 and stores software programs, various data, and the like. Note that the storage device 2 may be a volatile memory device.

  The nonvolatile storage device 3 is a nonvolatile storage device such as a magnetic disk drive or a semiconductor storage device using a flash memory. The non-volatile storage device 3 can store various software programs and data. For example, information related to the water distribution network provided by the water distribution network information input device 101, information related to the parameters provided by the parameter information input device 102, plan information provided by the information input device 101, etc. may be stored in the nonvolatile storage device 3. Good.

  The network interface 6 is an interface device connected to a communication network. For example, a wired and wireless LAN (Local Area Network) connection interface device, a SAN connection interface device, or the like may be employed.

  The drive device 4 is, for example, a device that processes reading and writing of data with respect to a recording medium 5 described later.

  The recording medium 5 is a recording medium capable of recording data, such as an optical disk, a magneto-optical disk, and a semiconductor flash memory.

  The input / output interface 7 is a device that controls input / output with an external device.

  The water distribution operation system (or its constituent elements) in the present invention described by taking each embodiment described above as an example can realize the functions described in each embodiment above, for example, with respect to the hardware device illustrated in FIG. It may be realized by supplying a software program. More specifically, for example, the present invention may be realized by the arithmetic device 1 executing a software program supplied to such a device. In this case, an operating system running on the hardware device, database management software, network software, middleware such as a virtual environment platform, etc. may execute part of each process.

  In each embodiment described above, each unit illustrated in each of the above drawings can be realized as a software module, which is a function (processing) unit of a software program executed by the hardware described above. However, the division of each software module shown in these drawings is a configuration for convenience of explanation, and various configurations can be assumed for implementation.

  When each component of the water distribution operation system illustrated in FIGS. 1, 2, and 21 is realized as a software module, for example, these software modules are stored in the nonvolatile storage device 3. And when the arithmetic unit 1 performs each process, these software modules are read to the memory | storage device 2. FIG.

  In addition, these software modules may be configured to transmit various data to each other by an appropriate method such as shared memory or inter-process communication. With such a configuration, these software modules can be connected so as to communicate with each other.

  Further, the software program may be recorded on the recording medium 5. In this case, the software program may be configured to be stored in the nonvolatile storage device 3 through the drive device 4 as appropriate at the shipping stage or the operation stage of the water distribution operation system.

  In the above case, the method of supplying various software programs to the hardware is installed in the apparatus using an appropriate jig in the manufacturing stage before shipment or the maintenance stage after shipment. A method may be adopted. As a method for supplying various software programs, a general procedure may be adopted at present, such as a method of downloading from the outside via a communication line such as the Internet.

  In such a case, the present invention can be considered to be configured by a code that constitutes the software program or a computer-readable recording medium on which the code is recorded. In this case, the recording medium is not limited to a medium independent of the hardware device, but includes a recording medium in which a software program transmitted via a LAN or the Internet is downloaded and stored or temporarily stored.

  Further, the water distribution operation system described above includes a virtual environment (for example, a cloud computing environment) in which the hardware device illustrated in FIG. 22 is virtualized, and various software programs (computer programs) executed in the virtual environment. ). In this case, the components of the hardware device illustrated in FIG. 22 are provided as virtual devices in the virtual environment. In this case as well, the present invention can be realized with the same configuration as the case where the hardware device illustrated in FIG. 22 is configured as a physical device.

  In the above, this invention was demonstrated as an example applied to exemplary embodiment mentioned above. However, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various modifications and improvements can be made to such embodiments. In such a case, new embodiments to which such changes or improvements are added can also be included in the technical scope of the present invention. Furthermore, the embodiments described above, or embodiments obtained by combining the new embodiments with such changes or improvements can also be included in the technical scope of the present invention. This is clear from the matters described in the claims.

  This application claims the priority on the basis of Japanese application Japanese Patent Application No. 2015-209603 for which it applied on October 26, 2015, and takes in those the indications of all here.

DESCRIPTION OF SYMBOLS 1 Computation device 2 Storage device 3 Non-volatile storage device 4 Drive device 5 Recording medium 6 Network interface 7 Input / output interface 100 Water distribution operation system 101 Water distribution network information input device 102 Parameter information input device 103 Water distribution plan creation device 104 Output device 105 Model creation Device 200 Water distribution operation system 201 Information input unit 202 Water distribution plan creation unit

Claims (13)

Information input means for providing plan creation information used for creating a water distribution plan in a water distribution network including one or more facilities and a pipeline connecting the facilities;
Based on the plan creation information, by obtaining a solution of an optimization problem including at least the power consumption cost of the pumps installed in one or more of the facilities and the cost of changing the operation pattern of the pumps in the facilities, A water distribution operation system comprising: a water distribution plan creation means for creating a pump operation plan including an operation pattern of the pump and an output water amount from the pump. The water distribution operation system according to claim 1, wherein the water distribution plan creation means represents a change cost of the pump operation pattern using a model representing an operation state of the pump operation pattern. The water distribution planning means is
The operating state of the pump operating pattern is represented using a variable indicating whether the pump is operating according to the operating pattern of the pump,
The change cost of the pump operation pattern is expressed using a first cost function that is a function that takes the variable as an input and increases an output value according to a change in the variable,
The water distribution operation system according to claim 2, wherein the optimization problem that minimizes an objective function including at least the first cost function is set. The water distribution planning means is
When the variable representing the operating state of the pump operating pattern in the optimization problem is a discrete variable, an optimization problem approximating the optimization problem is set by approximating the discrete variable using a continuous function The water distribution operation system according to claim 3. The water distribution planning means is
The discrete variable representing the operating state of the pump operating pattern, the variable representing the operating state of the pump operating pattern in a certain time interval, and the variable representing the operating state of the pump operating pattern in another time interval Expressed using the L ₀ norm of the difference from
The water distribution operation system according to claim 4. The water distribution planning means is
Using the second cost function that approximates the power consumption of the pump using the output water amount for each operation pattern of the pump as an input, and the function that outputs the power consumption in the operation pattern using a piecewise linear function Represent,
The water distribution operation system according to any one of claims 3 to 5, wherein the optimization problem that minimizes the objective function further including the second cost function is set. The said water distribution plan preparation means is a water distribution operation system in any one of Claim 4 thru | or 6 which represents the said 1st cost function using following Formula (S1).

The water distribution operation system according to claim 6 or 7, wherein the water distribution plan creation means represents the second cost function using the following equation (S2).

The water distribution operation according to claim 7 or 8, wherein the water distribution plan creation means further sets the optimization problem that minimizes the objective function further including a third cost function represented by the following equation (S3). system.

The water distribution planning means is
The optimization problem for minimizing the objective function represented by the following equation (S4) including the first cost function, the second cost function, the third cost function, and a penalty function Set an approximate DC (Difference of Convex Functions) planning problem,
An optimal solution of the optimization problem is obtained by solving the DC planning problem using DCA (Difference of Convex functions Algorithm),
The water distribution operation system according to claim 9, wherein the pump operation plan is created based on the optimum solution.

The said water distribution plan creation means creates the flow rate plan for every certain time section regarding the said pipe line which connects between the said facilities by solving the DC plan problem which approximated the said optimization problem. Water distribution operation system. Based on plan creation information used for creating a water distribution plan in a water distribution network including one or more facilities and a pipeline connecting the facilities, at least power consumption of pumps installed in the one or more facilities Water distribution that creates a pump operation plan including the operation pattern of the pump and the amount of output water from the pump by obtaining a solution to the optimization problem including the cost and the switching cost of the operation pattern of the pump in the facility Operation method. A process for providing plan creation information used for creating a water distribution plan in a water distribution network including one or more facilities and a pipeline connecting the facilities;
Based on the plan creation information, timing is obtained by finding a solution of an optimization problem including at least the power consumption cost of the pumps installed in the one or more facilities and the switching cost of the operation pattern of the pumps in the facility. A recording medium on which a computer program for causing a computer to execute a pump operation plan including an operation pattern of the pump and an output water amount from the pump is recorded.

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