JP6847606B2 - Water distribution pump control device, water distribution pump control method, water distribution pump control system and computer program - Google Patents

Description

Embodiments of the present invention relate to a water distribution pump control device, a water distribution pump control method, a water distribution pump control system, and a computer program.

In the water distribution network of the water supply, the water distribution pump distributes water at an appropriate pressure so that water is not sent out and all consumers can use the water. However, an excessively high distribution pressure may lead to an increase in power consumption by the distribution pump and an increase in the amount of water leakage from the distribution pipe. Therefore, the pressure of the water distribution pipe network is maintained at the minimum necessary pressure at the point where the pressure is the lowest (hereinafter referred to as "terminal") in each small distribution area (hereinafter referred to as "water distribution block"). It is desirable to be adjusted so as to. The pressure at the point where the pressure becomes the lowest in each water distribution block is called the terminal pressure, and the control method for appropriately maintaining the pressure of the water distribution pipe network by controlling the terminal pressure as described above is generally referred to as terminal pressure control. Are known. In general, terminal pressure control is often performed independently for each distribution block.

On the other hand, when considering the operation of all distribution blocks, it is desirable to provide a connecting pipe between each distribution block so that water can be interchanged between each distribution block. However, the inflow and outflow of water between the distribution blocks interferes with the end pressure control for each distribution block, and can be a factor that reduces the accuracy of the control. Therefore, when controlling the distribution pump based on the terminal pressure in a distribution pipe network in which each distribution block exchanges water with each other, consideration is given to the balance of the entire distribution pipe network and interference between each distribution block. There is a need to. Several control methods have been proposed to solve such problems, but none of them has a high affinity with the existing system that controls the end pressure for each water distribution block, and it is not always easy. It may not be applicable to existing systems.

Japanese Unexamined Patent Publication No. 58-82317 JP-A-59-174094 Japanese Unexamined Patent Publication No. 6-2800 Japanese Unexamined Patent Publication No. 6-306893

The problem to be solved by the present invention is to more easily realize the control of the water distribution pump based on the terminal pressure in the water distribution pipe network configured so that the water distribution blocks can exchange water with each other. It is to provide a water distribution pump control device, a water distribution pump control method, a water distribution pump control system, and a computer program that can be used.

The water distribution pump control device of the embodiment includes a pressure information acquisition unit and a control unit. The pressure information acquisition unit measures or estimates the pressure at a predetermined position in the water distribution pipe network in the first water distribution block among the plurality of water distribution blocks in the water distribution pipe network of the distribution area divided into a plurality of water distribution blocks. The first pressure information indicating the value and the second pressure information indicating the measured value or the estimated value of the pressure at a predetermined position in the water distribution pipe network in the second water distribution block adjacent to the first water distribution block are provided. get. The control unit has the pressure indicated by the first pressure information based on the first and second pressure information and the control target given to the first water distribution pump that distributes water in the first water distribution block. The control target is corrected so that the difference between the pressure and the pressure indicated by the second pressure information becomes small. The control unit corrects the control target and determines the operation amount of the first water distribution pump by distributed cooperative control with the adjacent water distribution block, and realizes the distributed cooperative control by the consensus gradient algorithm.

The figure which shows the specific example of the distribution area in which the distribution pump is controlled by the distribution pump control device of embodiment. The block diagram which shows the specific example of the functional structure of the water distribution pump control device 1 of embodiment. The flowchart which shows the flow of the process performed by the water distribution pump control device 1 of embodiment. The figure which shows the outline of the PID control in an embodiment.

Hereinafter, the water distribution pump control device, the water distribution pump control method, the water distribution pump control system, and the computer program of the embodiment will be described with reference to the drawings.

(Embodiment)
FIG. 1 is a diagram showing a specific example of a distribution zone in which a distribution pump is controlled by the distribution pump control device of the embodiment. The distribution zone A shown in FIG. 1 includes five small distribution zones of distribution blocks B1 to B5. A closed water pipe network Wi (i = 1, 2, ..., 5) is laid in each water distribution block Bi (i = 1, 2, ..., 5). Each water pipe network Wi is connected to the water pipe network of the adjacent water distribution block by a connecting pipe Cij (i = 1, 2, ..., 5, j = 1, 2, ..., 5). Here, Cij represents a connecting pipe connecting the water distribution block Bi and the water distribution block Bj.

A water storage facility Ti (i = 1, 2, ..., 5) for storing water supplied in each water distribution block is installed in each water distribution block Bi, and the water stored in the water storage facility Ti is stored in the water storage facility Ti. It is sent to the water distribution pipe network Wi by the water distribution pump Pi (i = 1, 2, ..., 5) provided in. Further, at the end of each water pipe network Wi, a pressure gauge Si (i = 1, 2, ..., 5) for measuring the water pressure (terminal pressure) of the water pipe is installed. The pressure gauge Si measures the terminal pressure at a predetermined cycle, and the discharge pressure of the water distribution pump Pi is controlled based on the terminal pressure of the water distribution pipe network Wi measured by the pressure gauge Si. Although FIG. 1 shows one water distribution pump for each water distribution block for convenience of explanation, there may be a plurality of water distribution pumps for each water distribution block.

FIG. 2 is a block diagram showing a specific example of the functional configuration of the water distribution pump control device 1 of the embodiment. The water distribution pump control device 1 includes a CPU (Central Processing Unit), a memory, an auxiliary storage device, and the like connected by a bus, and executes a water distribution pump control program. The water distribution pump control device 1 functions as a device including a storage unit 101, an input unit 102, a communication unit 103, a terminal pressure information acquisition unit 104 (pressure information acquisition unit), and a control unit 105 by executing a water distribution pump control program. Even if all or part of each function of the water distribution pump control device 1 is realized by using hardware such as ASIC (Application Specific Integrated Circuit), PLD (Programmable Logic Device), and FPGA (Field Programmable Gate Array). Good. The distribution pump control program may be recorded on a computer-readable recording medium. The computer-readable recording medium is, for example, a flexible disk, a magneto-optical disk, a portable medium such as a ROM or a CD-ROM, or a storage device such as a hard disk built in a computer system. The distribution pump control program may be transmitted via a telecommunication line.

The storage unit 101 is configured by using a storage device such as a magnetic hard disk device or a semiconductor storage device. The storage unit stores information such as various setting information and measurement data necessary for controlling the water distribution pump.

The input unit 102 is configured by using an input device such as a mouse, a keyboard, and a touch panel. The input unit 102 receives the user's information input to the own device and outputs the input information to another function unit that requires the input information.

The communication unit 103 includes a communication interface for connecting the own device to the network. The communication unit 103 communicates with the pressure gauge and the water distribution pump of the water distribution block (hereinafter referred to as “own block”) under the control of the own device, and communicates with the water distribution block adjacent to the own block (hereinafter referred to as “adjacent block”). Communicate with the pressure gauge.

The terminal pressure information acquisition unit 104 acquires the self-terminal pressure information indicating the terminal pressure in the own block and the adjacent terminal pressure information indicating the terminal pressure in the adjacent block. These end pressure information is generated by the pressure gauge of each distribution block measuring the end pressure of each distribution block. The end pressure information acquisition unit 104 acquires the own end pressure information and the adjacent end pressure information from each pressure gauge by communicating with the pressure gauges of the own block and the adjacent block via the communication unit 103. The terminal pressure information acquisition unit 104 stores the acquired terminal pressure information in the storage unit 101.

The terminal pressure information acquisition unit 104 has a water demand estimation function and a terminal pressure estimation function, and the terminal pressure estimated as necessary may be included in the own terminal pressure information or the adjacent terminal pressure information. For example, the terminal pressure information acquisition unit 104 estimates the terminal pressure in the following cases.

(1) When a large number of pressure gauges are installed in the water distribution pipe network Fig. 1 illustrates the case where the pressure gauges are installed at predetermined predetermined terminal points, but in reality, the water distribution pipes are installed. Pressure gauges may be installed at multiple points in the network. In such a case, the terminal pressure information acquisition unit 104 may select the smallest value among the plurality of measured pressure values as the terminal pressure. Further, the terminal pressure information acquisition unit 104 may estimate the terminal pressure by using a plurality of measured pressure values and information on the water distribution pipe network. For example, if the pressure is measured in the middle of a water pipe, the pressure should drop further beyond that point. In such a case, if the information on the distribution pipe network can be obtained, the pressure loss due to the pipes beyond that point can be estimated. If the pressure corresponding to this loss is estimated, the pressure of the terminal candidate existing before the measurement point can be estimated. In this way, the end pressure information acquisition unit 104 can estimate the pressure of the end candidate for each water pipe and acquire the minimum value of the estimated end candidate pressure as the end pressure.

(2) When the pressure gauge is not installed but the water demand can be measured in detail Even if the pressure gauge is not installed in the water distribution pipe network, the detailed water demand can be measured due to the spread of smart meters and the like. It may be possible to measure. In such a case, the terminal pressure can be estimated by performing a pipe network analysis using the measured value of the water demand amount and the measured value of the discharge pressure of the water distribution pump. Specifically, the pressure distribution of the distribution pipe network is calculated by the pipe network analysis, and the end pressure can be obtained by setting the point where the pressure is the lowest as the end.

(3) When the pressure and the water demand amount are partially measured In this case, first, the terminal pressure information acquisition unit 104 holds in advance a time-series water demand pattern for each water consumer. In addition, the terminal pressure information acquisition unit 104 indicates that for each water consumer in the distribution block, the total water demand of each water consumer is the average ratio of the total water demand in the water distribution block (hereinafter referred to as “)”. It is called "consumption ratio"). The terminal pressure information acquisition unit 104 acquires the measured value of the total water demand in each water distribution block at a predetermined frequency (for example, at a rate of several hours to once a day). The terminal pressure information acquisition unit 104 can estimate the amount of water demand for each water consumer by apportioning the acquired measured value according to the above water demand pattern and consumption ratio. The water demand of each consumer may be estimated by a method other than the above. For example, a more complex algorithm may be used to estimate water demand with high accuracy.

The terminal pressure information acquisition unit 104 can estimate the terminal pressure by performing a pipe network analysis using the estimated value of the water demand of each consumer acquired as described above. Here, the point where the pressure is the lowest may be set as the end from the result of the tube network analysis, but if the pressure can be measured at several points, the end pressure can be corrected by using the measured value. .. For example, the end pressure can be corrected based on the error between the result of the tube network analysis and the measured value. Alternatively, the terminal pressure can be obtained based on the pressure distribution estimated to minimize the error at the pressure measurement point by performing the tube network analysis by including the measured value of the pressure in the input by a method such as data assimilation. Is also possible.

The control unit 105 determines the indicated value of the discharge pressure of the water distribution pump of the own block based on the own terminal pressure information and the adjacent terminal pressure information. The control unit 105 notifies the water distribution pump of the own block of the determined indicated value by communicating with the water distribution pump of the own block via the communication unit 103.

Specifically, the control unit 105 determines the discharge pressure instructed to the water distribution pump of the own block by using the method of distributed cooperative control. Generally, the water distribution pump is independently distributed and controlled for each water distribution block that the water distribution pump is in charge of. However, when water is exchanged between distribution blocks via a connecting pipe, it is difficult to consider the influence of water flowing in and out through the connecting pipe with independent control for each distribution block. Therefore, the control unit 105 controls the water distribution pump of the own block by the distributed cooperative control between the own block and the adjacent block. Specifically, the control unit 105 controls the water distribution pump of its own block by the consensus gradient algorithm shown in the following equation (1).

The consensus gradient algorithm of equation (1) includes a gradient method that uses information about the gradient of a function to search for an optimal solution and an agreement algorithm that realizes consensus control that converges multiple controlled objects to the same state in an optimization problem. It is a combination. The first term on the right side of the equation (1) is a term based on the gradient method (hereinafter referred to as "gradient term"), and the second term is a term based on the consensus algorithm (hereinafter referred to as "agreement term"). Also, the set M _i represents a set of identifiers of its own block i and its adjacent blocks j.

Hereinafter, the gradient term and the consensus term in the equation (1) will be described. First, the gradient term will be described. P _i included in the gradient term represents the measured value of the end pressure of the self block i (or the estimated value), f i _{(P i)} denotes the evaluation function used in the search of the optimal solution by a gradient method. _{Specifically,} f i _{(P i)} is expressed by the following equation (2).

In the formula (2), _{Pi_ref} represents the target value of the terminal pressure of the own block i. That is, the equation (2) represents an evaluation function of an optimization problem for the purpose of minimizing the sum of squares of the error between the target value of the terminal pressure and the measured value. Incidentally, in such a terminal pressure optimization problem needs to be a _{P i> P i_ref} reasons described below. The purpose of control by the water distribution pump control device 1 of the embodiment is to keep the terminal pressure at the required minimum value, and the required minimum value is set as a target value of _{Pi_ref.} Evaluation function of formula (2) _is a cost function that minimizes the square error _{P i_ref} and _{P i, P i} that is not allowed to be smaller than _{P i_ref.} Therefore, the end pressure optimization problem as a constraint condition for the evaluation function of equation _(2), it is necessary to consider the _{P i>} P _{i_ref.} However, in distributed control, it is often difficult to incorporate constraints directly into the evaluation function. _Therefore, the penalty term penalizing in the case of P _{i <P i_ref} may be added to equation (1). The method of adding a penalty term to the evaluation function in this way is generally called the penalty function method, and is known as one of the methods for solving a constrained optimization problem.

In addition to the purpose of minimizing the error between the target value of the terminal pressure and the measured value, the evaluation function of the equation (2) may incorporate a term for optimizing other evaluation indexes. For example, the evaluation function may include a term aimed at minimizing the energy consumption of the water distribution pump while minimizing the error between the target value and the measured value of the terminal pressure. The evaluation function in this case is expressed by, for example, the following equation (3).

_{Q i} in the formula (3) is the energy consumption of the water distribution pump or the amount that can be converted into the energy consumption. For example, q _i may be the discharge pressure. λ is a coefficient that weights the energy consumption against the squared error of the terminal pressure. A penalty term may be added to the equation (3) as in the equation (2).

On the other hand, P _j included in the consensus term represents a measured value (or an estimated value) of the terminal pressure of the _{adjacent block j, and bij} is a parameter (hereinafter, may be an estimated value) that realizes consensus control of the own block i with respect to the adjacent block j. It is called "agreement parameter"). Specifically, the consensus parameter _bij realizes the control objective represented by the following equations (4) and (5).

Equation (4) expresses the control purpose of minimizing the squared error of the terminal pressure in each distribution block in the entire distribution zone. In the formula (4), _{w i} is the water distribution block (i = 1,2, ..., 5 ) is a parameter representing the weight for the evaluation function. Incidentally, importance of each water distribution block is the same, or when there is no need to distinguish between the importance of each water distribution block, may be set for every water distribution block i and w _{i =} 1. Equation (5) expresses the control purpose of reducing (approaching zero) the pressure difference between the terminal pressure of the own block i and the terminal pressure of the adjacent block j.

That agreement term represents the sum of the contribution of the terminal pressure P _j of the adjacent blocks j over end pressure P _i of the self block i.

The conditions for the consensus gradient algorithm to converge are shown in, for example, the following references.
Reference 1: Hatanaka et al., Distributed cooperative optimization and potential game for systems science and technology, measurement and control = Journal of the Society of Instrument and Control Engineers 51 (1), 49-54, 2012-01-10 Automatic measurement Control Society Reference 2: Iino et al., Sensor Network and Control Theory, Measurement and Control = Journal of the Society of Instrument and Control Engineers 47 (8), 649-656, 2008-08-10 Measurement and Control Society Reference 3: East other, control of the multi-agent system (system control Engineering Series), III consensus control (1), corona Publishing e.g., consensus gradient algorithm shown in equation (1) is, _b ij = 1 as an example / | _{M i} | a It can be converged by doing.

The control unit 105 calculates _Pi that realizes the control objectives shown in the equations (4) and (5) by solving the optimization problem by the consensus gradient algorithm of the equation (1). That is, in other words, by solving the optimization problem of the equation (1), _{the cooperative operation of the target value Pi_ref,} which is originally determined only by the gradient term, with the adjacent block is considered. It is equivalent to correcting to the target value.

The control unit 105 calculates the indicated value of the discharge pressure to the water distribution pump by using the _{Pi i} calculated in this way as a new target value Pi_ref of the terminal pressure. Specifically, the control unit 105 calculates the indicated value of the discharge pressure by applying the equation (1) to the control law of the water distribution pump (for example, the feedback control law).

In this case, in order to construct the control law of the distribution pump, a terminal pressure model showing the relationship between the discharge pressure of the distribution pump and the terminal pressure is required. In the present embodiment, the terminal pressure model is not limited to a specific model, but for example, the terminal pressure model represented by the following equation (6) is assumed.

In equation (6), g _i (P _i , P _j ) is a function represented by the terminal pressure of the water distribution block i and the terminal pressure of the adjacent block j. u _i represents the discharge pressure of the distribution pump of a water distribution block i, b _i is a coefficient parameter for converting the discharge pressure at the end pressure. For example, the function g _i is to construct a pipe network analysis model representing the dynamic pressure change in the water distribution network, enter the discharge pressure of the water distribution pumps for the pipe network analysis models as the operation amount, the step response It can be obtained by obtaining. In addition, the derivation of the function g _i, simplified tube network analysis model may be used. The following equation (7) is an equation showing an example of such a pipe network analysis model.

In the formula (7), i and j are identifiers of the nodes of the pipe network, and are different from the identifiers i and j of the water distribution block described above. p _i (t) represents the pressure [Pa] at the node i at time t. ν _ij (t) represents the flow velocity [m / s] at time t of the node i and the pipeline connecting the nodes j. H _i represents the elevation of the node i [m]. ρ represents the density [kg / m ³ ] of the fluid flowing through the pipeline. g represents the gravitational acceleration [m / s ² ]. _Lij represents the length [m] of the node i and the pipeline connecting the nodes j. D _ij represents the diameter [m] of the node i and the pipeline connecting the nodes j. λ _ij represents the friction loss coefficient of the node i and the pipeline connecting the nodes j. In equation (7), the first term on the right side represents the pressure loss due to the effective water pressure difference, the second term on the right side represents the pressure loss due to the difference in altitude, and the third term on the right side represents the friction between the fluid and the pipeline wall surface. Represents the pressure loss due to.

When the pipe network analysis model is expressed by the following equation (7), the control rule of the discharge pressure of the distribution pump is expressed by the following equation (8).

Control unit 105 transmits the discharge pressure u _i of distribution pump which is calculated based on the equation (8) as an instruction value to the distribution pump P _i.

FIG. 3 is a flowchart showing a flow of processing performed by the water distribution pump control device 1 of the embodiment. First, the terminal pressure information acquisition unit 104 acquires the terminal pressure of the own block (step S101). As described above, the terminal pressure information acquisition unit 104 may acquire the minimum pressure value indicated by the self-terminal pressure information as the terminal pressure, or may acquire the terminal pressure by estimation. Similarly, the terminal pressure information acquisition unit 104 acquires the terminal pressure of the adjacent block (step S102).

The terminal pressure information acquisition unit 104 corrects the target value of the terminal pressure of the own block based on the acquired terminal pressure of the own block, the terminal pressure of the adjacent block, and the target value of the terminal pressure of the own block ( Step S103). The terminal pressure information acquisition unit 104 determines the indicated value of the discharge pressure of the water distribution pump of the own block based on the corrected target value of the terminal pressure (step S104). When the consensus gradient algorithm is incorporated into the control law of the water distribution pump as in Eq. (8), step S103 and step S104 are not necessarily executed as separate steps, and even if they are executed in one step. Good.

The water distribution pump control device 1 of the embodiment configured in this way disperses and coordinates the target value of the end pressure of the own block for the purpose of reducing the difference between the end pressure of the own block and the end pressure of the adjacent block. It has a control unit that corrects by control and calculates the indicated value of the discharge pressure of the water distribution pump of its own block based on the corrected target value of the terminal pressure. By providing the water distribution pump control device 1 with such a configuration, it is easier to control the water distribution pump based on the terminal pressure in the water distribution pipe network configured so that the water distribution blocks can exchange water with each other. Can be realized.

Specifically, since the water distribution pump control method of the embodiment is a distributed cooperative control method, it does not require a central control device that controls the entire distribution area, and each distribution block has at least terminal pressure information of adjacent distribution blocks. Should be obtained. Further, since the water distribution pump control method of the embodiment has a good affinity with the gradient method generally used in the past, it can be more easily adapted to the distributed cooperative control.

The distribution pump of each distribution block performs distributed coordinated control with the adjacent distribution block by the distribution pump control device 1 of the embodiment, thereby reliably supplying the required amount of water to all consumers in all distribution zones. At the same time, it is possible to control the water distribution pump so as to minimize the power consumption and the amount of water leakage in the entire distribution area. Further, by performing such distributed cooperative control, even if the water distribution pump fails in any of the water distribution blocks, it is possible to supply water from the water distribution block adjacent to the water distribution block. Become. Therefore, the risk of water outage can be reduced.

<First modification>
In the first modification, when various actuators are installed in each distribution block in addition to the water distribution pump, a method of calculating the indicated value of the operation amount for the water distribution pump and these various actuators by the consensus gradient algorithm will be described. To do. For example, the actuator may be an electric valve that controls the flow rate of each connecting pipe, or may be a pressurizing pump that more positively controls the flow rate of each connecting pipe.

Under such a situation, in the control method in which the end pressure follows the target value as in the above embodiment, the number of manipulated variables is larger than the number of pressure gauges for measuring the controlled variables, which is redundant. Therefore, in such a case, the same control as in the above embodiment can be performed by appropriately installing the same number or more pressure gauges as the actuators other than the water distribution pump in the distribution area. If it is difficult to additionally install a pressure gauge, an estimated pressure value calculated by the same method as in the above embodiment may be obtained instead of the measured pressure value.

In this case, by incorporating the target value corresponding to each of the additionally acquired pressure values into the equation (1), the indicated value of the actuator operation amount can be acquired by the same method as that of the above embodiment. In this case, the evaluation function considering the power consumption of the actuator may be used as in the equation (2).

According to such a first modification, since the flow rate of the connecting pipe can be controlled, finer control than in the above embodiment is possible. In particular, when the water distribution pump of a certain water distribution block fails, the actuator can be operated so that water is supplied from the adjacent block to the water distribution block, so that the risk of water outage can be further reduced. become.

<Second modification>
In the second modification, in each water distribution block, a pressure gauge is installed at least at a point where the pressure is expected to be low (for example, a point at a high altitude or a point far away from the water distribution pump). A method of calculating the indicated value of the operation amount for the water distribution pump of each water distribution block by the agreed gradient algorithm will be described.

In the above embodiment, an example of realizing distributed cooperative control by a consensus gradient algorithm based on the terminal pressure measured by a pressure gauge installed at a point considered to be the end or the terminal pressure estimated at the point considered to be the end. As explained, in reality, it is assumed that the point where the terminal pressure is taken changes from moment to moment according to the amount of water demand of the consumer. In such a case, by transforming the evaluation function of the equation (1) as in the following equation (9), the consensus gradient algorithm can be made to correspond to the ever-changing end.

In the formula (9), j is an identifier of the pressure gauge installed in the water distribution block i. The number j of the pressure gauges installed for each water distribution block may be different. Further, restriction of _{P i_ref> P ij} between the formula (1) as well as _{P i_ref} and _{P ij} are present. This restriction also applies to the case where the evaluation function as in Eq. (2) is used.

According to such a second modification, by adding a constraint to select the end to the evaluation function, the end estimation that changes from moment to moment according to the water demand is performed independently of the distributed cooperative control. It is not necessary, and the same effect as that of the above embodiment can be obtained by simply changing the evaluation function as shown in the equation (9).

<Third modification example>
As described above, when performing distributed cooperative control using the equation (7), it is premised that the terminal pressure model has been constructed in advance. However, a lot of labor is required to construct a terminal pressure model representing the pressure distribution of the distribution area. On the other hand, the conventional control of the water distribution pump is often realized by PID (Proportional-Integral-Differential) control.

FIG. 4 is a diagram showing an outline of PID control. FIG. 4 shows a PID control device 20 that executes PID control for the controlled process 10. For example, the controlled process 10 corresponds to the end pressure control for each water distribution block. In this case, the manipulated variable of the controlled process 10 is the discharge pressure of the water distribution pump 30, and the controlled variable is the terminal pressure of each water distribution block measured by the pressure gauge 40. The PID control device 20 calculates a new discharge pressure that acts to bring the terminal pressure closer to the target value based on the measured value of the terminal pressure, and sets it in the water distribution pump 30. Since such PID control can be realized with a relatively simple configuration, it is a control method that is widely and generally used in the industrial world. In the third modification, the distributed cooperative control that extends the conventional PID control is realized by transforming the equation (7) as shown in the following equation (10).

The first term on the right side of the equation (10) is a term representing P control (proportional control) among PID controls, and K _p is a constant representing proportional gain. The second term represents the I control (integral control), K _i is a constant representing an integral gain. On the other hand, the third term represents an agreement term in distributed cooperative control.

Here, when a quadratic form evaluation function such as Eq. (1) is assumed as the evaluation function and a model called a first-order lag system is assumed as the terminal pressure model, Eq. (10) matches Eq. (5). .. From this, it can be seen that the distributed cooperative control (PI control + consensus control) according to the equation (10) is similar to the distributed cooperative control by the consensus gradient algorithm under certain specific conditions. Equation (10) does not necessarily match the consensus gradient algorithm when the form of the evaluation function is different or the assumption for the terminal pressure model does not hold, but it is expressed in the form of adding the consensus term to the conventional PI control. , It is considered that the affinity with the conventional PID control is high. Therefore, it is considered that the PID control performed for each water distribution block can be more easily made to correspond to the distributed cooperative control.

<Fourth modification>
In the third modification, a method of realizing distributed cooperative control by adding an agreement term to the conventional PI control was described, but in the fourth modification, extreme value control was used instead of the conventional PI control. A method for realizing distributed cooperative control will be described. The distributed cooperative control law in this case is expressed by the following equation (11).

A term representing the control system the first term of formula (11) is called the extreme control (Extremum Men Seeking Women Control) (also referred to as extreme search control), E _S is the extreme value control based on P _{i_ref} and P _i is a function for calculating a portion of the contribution of the control quantity u _i by. Since the details of extreme value control are described in various documents, the description thereof is omitted here (see, for example, the reference "Ariyur and Kristic," Real Time Optimization by Eextemum Seeking Control ", Wiley"). Extreme value control is a control method that searches for the extreme value (minimum point or maximum point) of an unknown evaluation function based on the value of the evaluation quantity acquired for each control cycle. Extreme value control does not require a model of the controlled process, so it can be applied to control a wide variety of processes.

The second term on the right side of the equation (11) is the same consensus term as the third modification. In this way, by adding the consensus term in the distributed cooperative control to the control term (first term on the right side) for each water distribution block, it is possible to make the individual control for each water distribution block correspond to the distributed cooperativeness.

<Fifth variant>
In the fifth modification, a control method for dynamically changing the adjacent block to be the target of the distributed cooperative control will be described according to the value of the evaluation function. In the embodiments and modifications described above, as a condition for the optimization, but was required to be a P _i> P _{i_ref,} and if the distribution pump of a water distribution block fails, there the water at a specific water distribution block In the event of an abnormality such as a sudden increase in demand, a large amount of water leaking from a pipeline in a specific water distribution block, or a break in a pipeline in a specific water distribution block, the terminal pressure will be as described above. It is assumed that the conditions cannot be satisfied.

The fifth modification is a control method that assumes such a case and changes the range of adjacent blocks to be subject to distributed cooperative control according to the situation of the own block. Hereinafter, the water distribution block B1 shown in FIG. 1 will be described as an example. The water distribution block B1 is connected to the water distribution block B2, the water distribution block B3, and the water distribution block B5 by a connecting pipe. _{Therefore, in the normal state, the set N 1} of the identifiers representing the water distribution blocks adjacent to the water distribution block B1 _{is expressed as N 1} = {2, 3, 5}. In this case, the adjacent block is changed as follows, for example.

(1) In the case of _{P 1} > P _{1_ref N 1} = {2, 3, 5}
(2) In the case of _{P 1} <P _{1_ref N 1} = {2,3,4,5}

That is, when the terminal pressure of the water distribution block B1 falls below the target value (in the case of (1) above), not only the water distribution block directly connected by the connecting pipe but also the water distribution block B2 and the water distribution block B3 are used. The indirectly connected water distribution block B4 is also defined as an adjacent block. In FIG. 1, since the distribution zone is composed of only five distribution blocks, all distribution blocks are defined as adjacent blocks when the terminal pressure is significantly lower than the target value, but this is not necessarily all distribution. It does not mean that the block is defined as an adjacent block. In general, it means that a water distribution block adjacent to an adjacent block is added to a new adjacent block when the end pressure is significantly below the target value.

When the range of the adjacent block is changed according to the situation of the own block as described above and it becomes impossible to secure the minimum necessary terminal pressure in some water distribution blocks for some reason, the water distribution block is subjected to. It will be possible to back up the water supply throughout the distribution area.

According to at least one embodiment described above, the measured value or estimated value (first pressure information) of the pressure at a predetermined position in the water distribution pipe network in the own block and the predetermined position in the water distribution pipe network in the adjacent block. Based on the pressure information acquisition unit that acquires the measured or estimated pressure value (second pressure information), the pressure information of the own block and the adjacent block, and the control target given to the water distribution pump of the own block. By having a control unit that corrects the control target, it is easier to control the water distribution pump based on the terminal pressure in the water distribution pipe network configured so that the water distribution blocks can exchange water with each other. It can be realized.

Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, as well as in the scope of the invention described in the claims and the equivalent scope thereof.

1 ... Water distribution pump control device, 101 ... Storage unit, 102 ... Input unit, 103 ... Communication unit, 104 ... Terminal pressure information acquisition unit, 105 ... Control unit, 10 ... Control target process, 20 ... Control device, 30 ... Water distribution pump , 40 ... pressure gauge, A ... distribution area, B1 to B5 ... water distribution block, Bi, Bj ... water distribution block, Cij ... connecting pipe, Pi ... water distribution pump, Si ... pressure gauge, Wi ... water distribution pipe network

Claims (10)

In the water distribution pipe network of the distribution area divided into a plurality of water distribution blocks, the first one showing the measured value or the estimated value of the pressure at a predetermined position in the water distribution pipe network in the first water distribution block among the plurality of water distribution blocks. A pressure information acquisition unit that acquires pressure information and second pressure information indicating a measured value or an estimated value of pressure at a predetermined position in a water pipe network in a second water distribution block adjacent to the first water distribution block. When,
Based on the first and second pressure information and the control target given to the first water distribution pump that distributes water in the first water distribution block, the pressure indicated by the first pressure information and the first. A control unit that corrects the control target so that the difference from the pressure indicated by the pressure information of 2 becomes small,
Equipped with a,
The control unit corrects the control target and determines the operation amount of the first water distribution pump by distributed cooperative control with an adjacent water distribution block, and realizes the distributed cooperative control by a consensus gradient algorithm. apparatus. The predetermined position is the minimum pressure point in the distribution pipe network in the first distribution block or the second distribution block.
The water distribution pump control device according to claim 1. The pressure information acquisition unit acquires pressure information in time series at a plurality of positions in the first water distribution block or the second water distribution block.
The control unit selects the pressure minimum point at that time from a plurality of positions in the first water distribution block or the second water distribution block based on the pressure information, and the pressure information of the selected pressure minimum point. Correct the control target based on
The water distribution pump control device according to claim 2. The pressure information acquisition unit estimates the pressure at the minimum pressure point in the first water distribution block or the second water distribution block by water demand forecast or pipe network analysis, and obtains information indicating the estimated pressure. The first pressure information or the second pressure information.
The water distribution pump control device according to claim 2 or 3. The control unit corrects the control target and determines the operation amount of the first water distribution pump by distributed cooperative control with an adjacent water distribution block, and the distributed cooperative control is combined with PID control and consensus control. Realized by algorithm,
The water distribution pump control device according to any one of claims 1 to 4. The control unit corrects the control target and determines the operation amount of the first water distribution pump by distributed cooperative control with an adjacent water distribution block, and the distributed cooperative control is combined with extreme value control and consensus control. Realized by the algorithm
The water distribution pump control device according to any one of claims 1 to 4. The control unit changes the second water distribution block to another water distribution block based on a predetermined condition.
The water distribution pump control device according to any one of claims 1 to 6. The water distribution pump control device according to any one of claims 1 to 7 is provided.
Each of the water distribution pump control devices corrects the control target based on the first and second pressure information and the control target given to the first water distribution pump that distributes water in the first water distribution block. To do
Water distribution pump control system. In the water distribution pipe network of the distribution area divided into a plurality of water distribution blocks, the first one showing the measured value or the estimated value of the pressure at a predetermined position in the water distribution pipe network in the first water distribution block among the plurality of water distribution blocks. Pressure information acquisition step of acquiring pressure information and second pressure information indicating a measured value or an estimated value of pressure at a predetermined position in a water pipe network in a second water distribution block adjacent to the first water distribution block. When,
Based on the first and second pressure information and the control target given to the first water distribution pump that distributes water in the first water distribution block, the pressure indicated by the first pressure information and the first. It is a step of correcting the control target so that the difference from the pressure indicated by the pressure information of 2 becomes small, and the correction of the control target and the determination of the operation amount of the first water distribution pump are performed with the adjacent water distribution block. The control step that realizes the distributed cooperative control by the agreed gradient algorithm, and
Water distribution pump control method having. In the water distribution pipe network of the distribution area divided into a plurality of water distribution blocks, the first one showing the measured value or the estimated value of the pressure at a predetermined position in the water distribution pipe network in the first water distribution block among the plurality of water distribution blocks. Pressure information acquisition step of acquiring pressure information and second pressure information indicating a measured value or an estimated value of pressure at a predetermined position in a water pipe network in a second water distribution block adjacent to the first water distribution block. When,
Based on the first and second pressure information and the control target given to the first water distribution pump that distributes water in the first water distribution block, the pressure indicated by the first pressure information and the first. It is a step of correcting the control target so that the difference from the pressure indicated by the pressure information of 2 becomes small, and the correction of the control target and the determination of the operation amount of the first water distribution pump are performed with the adjacent water distribution block. A control step that is performed by the distributed cooperative control of the above and realizes the distributed cooperative control by the agreed gradient algorithm, and
A computer program that lets a computer run.

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