JP2601895B2 - Water distribution network controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a water distribution pipe network control device in a drainage facility such as a water supply system.

(Prior art) In general, in water distribution facilities, water pressure in the distribution network changes due to fluctuations in the flow rate in the distribution network. Need to be kept.

Therefore, in the conventional water distribution network control device, the water pressure in the water distribution network is controlled by measuring the water pressure at a specific point and comparing it with the reference pressure, and controlling the discharge pressure of the pressure source and the water pressure at the pressure reduction point. Like that.

In addition, the water pressure in the distribution pipe network is calculated using a pipe network model created based on the actual piping diagram and a water supply model simulating the outflow at the water supply point, and the pressure source is adjusted so that this water pressure falls within the allowable range. The control of the water pressure is also performed by determining the rotation speed of the pump and the opening degree of the control valve as the pressure reducing point.

(Problems to be Solved by the Invention) However, in such a conventional water distribution network control device, since the entire water pressure is controlled by checking the water pressure at a certain specific point, the water pressure at other points is not controlled. In some cases, the upper and lower limits may be deviated from the allowable range, and there is a problem that the water pressure becomes too low or conversely becomes too high.

Also, it is difficult to accurately simulate a pipe network model or a water supply model, and there has been a problem that depending on the accuracy of the model, it may not be possible to achieve proper water pressure in a distribution pipe network.

An object of the present invention is to provide a water distribution network control device capable of performing stable water pressure management of a water distribution network at an appropriate water pressure in view of such conventional problems.

[Structure of the Invention] (Means for solving the problem) A water distribution network control device of the present invention includes a pressure gauge, a flow meter, and control points (pumps and valves) installed at each point in a water distribution network.
Knowledge of the target model consisting of a database of the actual process values from the system and the relationship between the operation of each control point and the pressure change at each point for this operation, the change in water supply in the distribution network and the pressure at each point for this change Knowledge base on the demand model consisting of the relationship with the change, and knowledge for controlling the pressure in the water distribution network, which is constructed with knowledge about the control in consideration of the guidelines of the water distribution network operation bill, and the database, Means for inferring the correction amount of the operation amount of the control point based on the data from the knowledge base; and water pressure for adjusting the water pressure of each point based on the correction amount of the operation amount of the control point determined by the inference means. Control means.

(Operation) In the water distribution network control device of the present invention, the inference means
It consists of process data such as water pressure and flow rate in the water distribution network and information on control points (pumps and valves), knowledge on the target model and demand model, and knowledge on control, as well as knowledge on guidelines for the water distribution network operation bill. Infer the correction amount of the control point operation amount based on the knowledge base, and control the water pressure at each point by correcting the operation amount of the control point based on the correction amount by the water pressure control means. Optimize water pressure at each point.

Then, even if there is a change in the distribution system or distribution pipe network operation plan, etc., the knowledge base is modified and rebuilt based on the changed feeder know-how to flexibly respond to changes in plant characteristics. To

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, and FIG. 2 is a flowchart for explaining the operation. This embodiment relates to a water distribution network of a water supply system, and water is distributed from a reservoir 1 to a water distribution network 3 through a water distribution pipe 2. Control valves 4a and 4b are installed at various places in the distribution network 3 as means for controlling the distribution pressure.

The reservoir 1 is provided with a water level detector 5 for detecting the water level, and the water distribution pipe 2 is provided with a water distribution flow rate detector 6.

On the secondary side of the control valves 4a, 4b, control valve secondary pressure detectors 7a, 7b are provided. Further, at various points in the water distribution network 3, water pressure detectors 8a, 8b, 8c, 8d and flow rate detectors 9a, 9b, 9c, 9d in the distribution pipe network are provided.

For each of the control valves 4a and 4b, valve opening detectors 10a and 10b for detecting the valve opening are installed, and further, control valve control devices 11a and 11b for adjusting the valve opening are installed. .

A control system for controlling the control valve control devices 11a and 11b and controlling the valve opening degree of the control valves 4a and 4b includes a parameter setting device.
It comprises an input device 13, an operation control device 14, and an output device 15.

The parameter setting device 12 is for setting parameters such as a water pressure upper limit value δ ₁ , a water pressure lower limit value δ _{2 and the} like.
These parameters are input to the arithmetic and control unit 14 via 3.

The input device 13 further controls the reservoir water level detector 5, the distribution flow rate detector 6, the control valve secondary pressure detectors 7a and 7b, the distribution pipe network water pressure detectors 8a, 8b, 8c, 8d, and the distribution pipe network flow rate. Detector 9a, 9
Various process values H, Q, h, q, u detected by b, 9c, 9d and the control valve opening detectors 10a, 10b are taken in, and these various parameters and process values are sent to the arithmetic and control unit 14. It is entered and stored as a database.

The arithmetic and control unit 14 includes an inference unit 14a, a database 14b, and a knowledge base 14c, and stores a process value detected from each detector at regular intervals τ.
The inference unit 14a infers the correction amount of the control valve opening based on the data from the qualitative model for the object, the qualitative model for the demand, and the knowledge base 14c storing the knowledge about the control, and corrects the correction amount of the control valve opening, and corrects the correction amount to the output device 15. The operation amount of the control valve is output.

Note that the knowledge base 14c in the present embodiment includes, as knowledge data relating to control, information that includes guidelines based on a water distribution system, a water distribution network operation plan, and the like by the processing shown in FIG. 3 as described later.

Next, the operation of the water distribution network control device having the above configuration will be described. Water is distributed from the reservoir 1 to the distribution network 3 via the distribution pipe 2.

The water level H of the reservoir 1, the flow rate Q of water distribution from the reservoir 1 by the water distribution pipe 2, the water pressure h and the water supply q at each point in the distribution pipe network 3, and the valve opening u of the control valves 4 a and 4 b are water level detection. Vessel 5,
Water distribution flow detector 6, control valve secondary pressure detectors 7a, 7b, water distribution network water pressure detectors 8a, 8b, 8c, 8d, distribution pipe network flow detector 9
a, 9b, 9c, 9d and detected by the control valve opening 10a, 10b,
The data is input to the arithmetic and control unit 14 via the input device 13.

Further, to the arithmetic and control unit 14, the pressure upper limit value Δ ₁ and the pressure lower limit value Δ ₂ are input as necessary parameters from the parameter setting device 12 via the input device 13.

The arithmetic and control unit 14 calculates the valve opening target value of each of the control valves 4a and 4b by the arithmetic operation shown in the flowchart of FIG. 2, and outputs the control valve control unit 11a of each of the control valves 4a and 4b via the output device 15. , 11b. Then, each control valve control device 11a, 1
1b, the control valves 4a, 4a
By controlling the valve opening of b, the water pressure in the water distribution pipe network 3 is optimized.

Next, the arithmetic operation in the arithmetic and control unit 14 is described as a second example.
This will be described with reference to the flowchart in FIG.

The arithmetic and control unit 14 receives the setting parameters δ ₁ and δ ₂ from the parameter setting unit 12 and stores them in the database 14b. If there is a change in the set value of the parameter in the parameter setting device 12, the change is taken in and stored in the database 14b (step 100).

Next, a function that operates periodically will be described. First, various process values H, Q, h, q, u are input from the detectors via the input device 13 and stored in the database 14b (step 110).

Next, the inference unit 14a calculates the process reservoir water level H,
The corrected control valve opening target value is inferred from the total water distribution flow rate Q, the distribution pipe network flow rate q, the pipe network pressure h, and the control valve opening u (step 120). In the inference unit 14a, the control valve 4a , 4b, a knowledge base constructed based on the influence of the pressure in the distribution network on the distribution volume and the effect of the pressure in the distribution network on the change of the water supply volume at the water supply point, and the knowledge of operation The corrected control valve opening target value is determined in accordance with the data of (1).

Here, the contents of the knowledge base 14c include knowledge on control in consideration of guidelines based on a water distribution system and a water distribution network operation plan, and knowledge on an object, and are constructed according to the procedure shown in the flowchart of FIG.

In FIG. 3, in step 201, the operation plan of the water distribution network is input. As this operation plan, the following plan serving as a control guide is input.

The water pressure in the distribution network is the water pressure upper limit δ ₁ and the water pressure lower limit δ ₂
Must be kept within the range.

If water pressure points of the distribution network is lower than the pressure lower limit value [delta] _2, when you try to hold the pressure lower limit, when there is point exceeds the pressure limit at other points will not exceed pressure upper range Operate the control valve opening with.

If water pressure points of the water distribution network exceeds the pressure upper limit value [delta] _1, when you try to hold the pressure limit, when there is point falls below the pressure limit at other points is not less than the water pressure lower limit range Operate the control valve opening with.

In step 202, the plant characteristic data is
Enter more. The following data is input as the plant characteristic data.

Piping system data (information on which pipes are connected to which pipes) Piping data (information on pipe lengths, diameters, and flow velocity coefficients) Water supply data (how much water is supplied from which water supply points Data on control valve (Characteristics and diameter of control valve) Data on water level measurement point installed in water distribution network In step 203, sensitivity analysis is performed based on the input plant characteristic data. This sensitivity analysis is to examine the characteristics of water pressure and flow rate in the distribution pipe network, and is performed using a pipe network calculation method. Then, how the water pressure at each measurement point changes when the operation amount of the control valve is changed several times is analyzed by a pipe network calculation method to obtain a qualitative model for the target. Also, how the water pressure at each measurement point changes when the water supply amount at the water supply point is changed in several steps is analyzed by the pipe network calculation method to obtain a qualitative model for demand. Based on the result analyzed in 203, an influence table between the control valve and the measurement point and an influence table between the water supply point and the measurement point are created. For example, the amount of operation of the control valve 4a affects the pressure in the pipe network water pressure detectors 8a, 8b, 8d.

The operation amount of the control valve 4b affects the pressures of the pipe network water pressure detectors 8b and 8c.

The change in the water supply amount qa of the water supply point A block affects the pressure of the pipe network water pressure detector 8a.

The change in the water supply amount qd of the water supply point D block affects the pressure of the pipe network water pressure detector 8d.

In step 206, knowledge on control based on the water distribution network operation plan is incorporated into the knowledge base 14c. This knowledge is incorporated into the knowledge base 14c as knowledge 14c- ₁ regarding control, and for example, the following rules are used.

Rule 300: IF “Hold pressure source” and “Some points are below the lower pressure limit” THEN “Modify control valves affecting points below the lower pressure source in the opening direction” Rule 310: IF “ The lower pressure limit is maintained and "there is a point above the upper pressure limit." THEN "The control valve affecting the point above the upper pressure limit is closed in a direction not lower than the lower pressure limit." Rule 400: IF “No point exceeds the lower pressure limit” and “No point exceeds the upper pressure limit” THEN “Since control is normal, keep the current status without modifying the current control valve opening.” Rule 510: IF “ Correct the control valve in the opening direction. "THEN" Calculate the correction amount of the control valve that affects the point below the lower pressure limit.

Rule 600: IF “correction amount kilo” THEN “control valve opening target value = current control valve opening + correction amount” These knowledges are not changed unless the operation plan is changed, but are changed to the distribution network operation plan. In the case where the above occurs, a control guideline based on a new operation plan is input as a rule.

On the other hand, the knowledge obtained in steps 204 and 205 is incorporated into the knowledge base 14c as the knowledge 14c-2 on the object, for example, according to the following rule.

Rule 700: IF “Control valve 4a is on” THEN “The water pressure measurement points in the distribution pipe network that affect the operation amount of control valve 4a are 8a, 8b, and 8d” Rule 800: IF “Measurement of water pressure in the distribution pipe network The water pressure change at the point 8a is large. "THEN" The water supply amount at the water supply point A block may have changed significantly. "Knowledge 14c-2 on these objects can be attributed to changes in plant characteristics, such as maintenance of distribution pipes and distribution systems. If there is no change, it is not changed, but if there is a change in the plant characteristics, it is reconstructed based on steps 201 to 205.

The control valve opening target value corrected by the inference of the inference unit 14a in this way is given to the output device 15, and the output device
15 gives a command output to the control valve control devices 11a and 11b for the control valves 4a and 4b, and delays by the control period (step 130 in FIG. 2).

Therefore, each of the control valve control devices 11a, 11b includes the control valve 4a,
Control the valve opening of 4b based on a command from the output device 15,
The water pressure h in the distribution pipe network 3 is within the operating range as much as possible (δ ₂ <
h <δ ₁ ).

In this manner, in this embodiment, the arithmetic and control unit 14 obtains a correction amount of the control valve opening by an inference operation based on the knowledge base 14c at regular intervals from fluctuations of the actual flow rate and water pressure to perform the valve opening control. It implements more detailed water pressure control.

The present invention is not limited to the above embodiment, but can be applied to water pressure control in a water distribution network by a water distribution pump, instead of water pressure control in a water distribution network by a control valve. In this case, the relationship between the rotation speed of the water distribution pump and the water pressure at each point in the distribution pipe network is converted into a knowledge base, and the pump rotation speed is controlled so that the water pressure at each point operates within the allowable upper and lower limits. To control.

Further, the present invention is not limited to the above embodiment, and various modifications can be made within the scope of the concept described in the claims.

[Effects of the Invention] As described above, according to the present invention, knowledge on control including a control guideline of a water distribution network operation plan is made based on a knowledge base of the movement of a complicated water distribution network process in the form of a target model and a demand model. By creating a knowledge base,
More flexible and detailed water pressure control becomes possible, and water pressure control according to the policy of operating the water distribution network becomes possible. In addition, since the construction of the knowledge base is based on the water distribution system and water distribution network operation plan, it is possible to flexibly respond to changes in plant characteristics and operation plan, and to optimize the hydraulic pressure without deteriorating control performance. Control becomes possible.

[Brief description of the drawings]

FIG. 1 is a system diagram of one embodiment of the present invention, FIG. 2 is a flowchart for explaining the operation of the above embodiment, and FIG. 3 is a flowchart for explaining a procedure for constructing knowledge data in a knowledge base in the above embodiment. It is. 1 ... distribution reservoir, 2 ... distribution pipe 3 ... distribution pipe network, 4a, 4b ... control valve 5 ... water level detector, 6 ... flow rate detector 7a, 7b ... control valve secondary pressure detector 8a, 8b, ... Water pressure detector in distribution network 9a, 9b, ... Flow detector in distribution network 10a, 10b ... Control valve opening detector 11a, 11b ... Control valve controller 12 ... Parameter Setting device 13 ... Input device, 14 ... Calculation device 14a ... Inference unit, 14b ... Database 14c ... Knowledge base, 15 ... Output device

Claims (1)

(57) [Claims] 1. A pressure gauge installed at each point in a distribution network,
A database of actual process values from flow meters and control points, knowledge of the target model consisting of the relationship between the operation of each control point and the pressure change at each point for this operation, changes in water supply in the distribution network and this change Knowledge base on the demand model consisting of the relationship with the pressure change at each point and the knowledge for controlling the pressure in the distribution network and the knowledge on the control in consideration of the guidelines of the distribution network operation bill Means for inferring the correction amount of the operation amount of the control point based on the data from the database and the knowledge base; and, based on the correction amount of the operation amount of the control point determined by the inference means, A water distribution network control device, comprising: water pressure control means for adjusting water pressure.