JPH0480804A - Rainwater pump controller - Google Patents

Abstract

PURPOSE:To automate the control of the number of pumps that is approximate to the intuition of an operator by performing the integrated decision based on the quantitative decision and the experiential decision and controlling the start or stop of the pump operation. CONSTITUTION:At a quantitative decision part 13, a knowledge base 18 is obtained based on a water level and an inflow rate and the quantitative decision in terms of a fact that the water level and the inflow rate are obtained from the numerical operations. At an experiential decision part 15, the number of operating pumps are adjusted based on the pump well level and the rainfall as well as the water level trend calculated by a water level trend calculation part 14. An integrated deciding part 16 performs the integrated decision based on the quantitative decision result of the part 13 and the experiential decision result of the part 15 and then outputs a start or stop command for operation of the pumps.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention is used in a pumping facility in which rainwater stored in a pump well in a rainwater drainage process is sucked up by a plurality of rainwater pumps and discharged into a river. The present invention relates to a system for controlling the number of pumps, and particularly to a system for controlling the number of pumps that can automatically control the number of pumps, reflecting the operator's empirical judgment and close to the operator's intuition.

(Prior art) Generally, a pumping facility in a sewerage system consists of a pump well and a plurality of rainwater pumps (hereinafter referred to as a pump group), and the pump well is connected to a plurality of underground pipes or conduits. This allows sewage including rainwater to flow into the area. In addition, the suction side of each pump in the pump group is connected to this pump well, so that the rainwater sucked up is discharged into the river. In this case, the discharge flow rate of the pump group can be changed in stages by changing the combination of pumps being operated.
Alternatively, it is partially adjusted continuously by speed control or discharge valve opening control.

By the way, sewage includes general drainage from homes, buildings, bathhouses, etc., as well as rainwater and groundwater. Of these, general drainage has a certain standard depending on whether it changes over time or on a weekly or daily basis. However, since rainwater and groundwater change depending on the region, weather, day of the week, time of the day, etc., even if we capture the amount of rainfall in each region or the flow rate flowing into a pump well through a pipe as a time-series change, the flow rate will not be the same. It changes each time and has poor reproducibility. Therefore, in order to make a daily pump operation plan, the predicted flow rate into the pump well is calculated over a sufficiently long period, but as mentioned above, the reproducibility is poor. , it is very difficult to obtain predicted values.

Therefore, pump operation control is normally performed by directly correlating the pump well water level with the total discharge flow rate of the pump group.

However, such operation control may not be able to cope with a sudden change in the water level of the pump well due to a large change in the flow rate, making it difficult to operate the pump unmanned. In addition, due to the poor reproducibility of the inflow flow rate as described above, skill is required to control the operation of the pump group, and accurate and reliable control cannot be performed without specialized knowledge. This fact also makes unmanned driving difficult.

Recently, in order to solve such problems, the present applicant has published, for example, "Japanese Patent Application Laid-open No. 1-175613".
A method of controlling the number of pumps in operation based on predicted water levels has been proposed, as shown in . That is, this method:
Sewage water such as sewage and rainwater flowing from pipes is stored in pump wells and then discharged to sewage treatment equipment by pump groups.In order to control the number of pump groups, water level gauges installed in pump wells and water level gauges installed on the discharge side of pump groups are used to control the number of pump groups. means for sequentially inputting the water level and total discharge flow rate respectively detected by the discharge flowmeter; means for estimating the inflow flow rate to the pump well by an autoregressive model based on the input water level and total discharge flow rate; Means for determining the maximum and minimum values of the discharge flow rate of a pump group based on a pump operation/stop command and a preset pump discharge flow rate versus water level characteristic; means for predicting and calculating the maximum and minimum values of the water level for a predetermined period of time based on the estimated inflow flow rate value and the current water level; A means for determining the number of operating units, a means for calculating a water level target value according to the determined number of operating units, and a means for executing flow rate control based on the number of operating units and the water level target value, In this method, the pump well water level after a certain period of time is predicted using the total discharge flow rate calculation value, and the number of pumps is controlled by comparing the predicted water level with the operation/stop water level.

However, this method of controlling the number of devices has the following problems. In other words, experienced operators at pump stations have operational know-how, such as how to use rainwater pumps of different capacities and how to set the pump start timing, in response to changes in the amount of inflowing sewage over time. For example, during heavy rain, we look at the rising trend of the pump well water level (hereinafter referred to as the trend), and if it shows the same rising trend, we start the pump a little earlier than during light rain to prevent a sudden rise in water level. try

However, the timing of turning on the pumps based on the operator's judgment of the situation cannot be controlled by the conventional system of controlling the number of pumps using the re-hell inch method (a method in which the relationship between the water level of the pump well and the number of pumps in operation is determined in advance). , could not be realized.

In addition, in the method of controlling the number of units using the predicted water level method described above,
Because pump well water level trends were not taken into account, the pump start/stop timing often did not match the operator's intuition. In this case, the operator may feel uneasy about the automatic operation of the pump, and may require manual intervention. Therefore, in recent years, there has been a strong demand for an automatic control system to control the number of pumps that reflects the know-how of operators as much as possible.

(Problems to be Solved by the Invention) As described above, the conventional control method has the problem that it is possible to achieve unmanned operation by controlling the number of pumps, but it is not possible to perform control that matches the intuition of the operator. Ta.

An object of the present invention is to provide an extremely reliable rainwater pump control device that can automatically control the number of pumps based on the operator's empirical judgment and is close to the operator's intuition. be.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the rainwater pump control device according to the present invention collects rainwater flowing into a pump well of a sewage pump station or a treatment plant by controlling multiple rainwater pumps. A pump well water level gauge installed in a pump well and a pump well water level gauge installed on the discharge side of a pump group is used in a pump facility that discharges water into a river by pumps, and determines the timing of starting or stopping a group of pumps and the increase or decrease in the number of pumps in operation. an inflow flow rate calculation means for calculating the inflow flow rate into the pump well based on the water level and total discharge flow rate respectively detected by the discharge flow meter; and a water level and total discharge a detected by the pump well water level meter and the discharge flow meter, respectively. A predicted water level calculation means predicts the water level of the pump well at a predetermined time based on the predicted water level, and an operator Based on the quantitative judgment means that determines whether to increase or decrease the number of pumps in operation by making quantitative judgments using knowledge-based rules that have accumulated empirical judgment knowledge as rules, and the water level detected by the pump well water level meter, Empirical determination using knowledge-based rules based on the water level trend calculation means that calculates the water level trend of the pump well, the water level trend calculated by the water level trend calculation means, the pump well water level, and the amount of rainfall if necessary. an empirical determination means for determining an increase or decrease in the number of pumps in operation;
Comprehensive determination means for making a comprehensive determination and outputting a command to start or stop pump operation based on the quantitative determination result by the quantitative determination means and the empirical determination result by the empirical determination means. are doing.

(Function) Therefore, in the rainwater pump control device of the present invention, in the quantitative determination, the inflow flow rate of the pump well is calculated from the pump well water level and the total discharge flow rate, for example, by an autoregressive model, and the total discharge flow rate of the pump group is calculated. The maximum and minimum values of the water level are calculated, and the maximum and minimum values of the water level for a predetermined time ahead are predicted from the maximum and minimum values of the discharge flow rate, the estimated inflow flow rate, and the current water level. Then, based on the obtained maximum predicted water level value and minimum predicted water level value, it is determined whether the number of pumps in operation should be increased or decreased.

On the other hand, in the empirical determination, the amount of change in the water level at the current time (water level trend) is calculated from the pump well water level a predetermined time ago, and the pump well water level and, if necessary, the rainfall intensity are observed. Based on these three factors, an increase or decrease in the number of pumps in operation is determined.

Next, the results of the quantitative judgment determined in this way,
The results of the empirical determination are comprehensively determined, and the final command for the number of pumps in operation (start or stop) is output.

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

FIG. 1 is a schematic diagram showing an example of the overall configuration when a rainwater pump control device according to the present invention is applied to a rainwater drainage pumping station.

In Figure 1, sewage such as sewage and rainwater flows from a pipe 1 buried underground at a rainwater pumping station, passes through a settling basin 2 and a screen 3 to remove solid matter, and then flows into a pump well 4. do. Rainwater out of the sewage stored in the pump well 4 is pumped and discharged into the river 6 by pump groups 5-1 to 5-n.

Further, the pump well 4 is provided with a pump well water level gauge 7, which sequentially detects the water level of the pump well 4.

Here, the water level of the pump well 4 has an upper limit value and a lower limit value. Further, a discharge flow meter 8 is provided on the discharge side of the pump groups 5-1 to 5-n.
The total discharge flow rate of n is sequentially detected. Furthermore, an above-ground rain gauge O is installed near the rainwater drainage pumping station to detect the amount of rainfall sequentially.

Then, the water level detected by the pump well water level gauge 7, the total discharge flow rate detected by the discharge flow meter 8, and the amount of rainfall detected by the ground rain gauge 0 are taken into the process interface 9.

On the other hand, the rainwater pump control device 10 of the present embodiment includes an inflow flow rate calculation section 11, a predicted water level calculation section 12, and a quantitative determination section 1.
3, a water level trend calculation section 14, an empirical judgment section 15, a comprehensive judgment section 16, and a man-machine interface 17.
and a knowledge base 18.

Here, the inflow flow rate calculation unit 11 uses the pump well water level and total discharge flow rate detected by the pump well water level meter 7 and the discharge flow meter 8 and taken in through the process interface 9 as human power, and calculates the pump well water level and total discharge flow rate. Based on this, the inflow flow rate to the pump well 4 is calculated. In addition, the predicted water level calculation unit 12 manually calculates the water level of the pump well 4 for a predetermined time based on the pump well water level and total discharge flow rate, which are also taken in through the process interface 9. It is a prediction. Furthermore, the quantitative determination unit 13
Based on the inflow flow rate calculated by the inflow flow rate calculation unit 11 and the predicted water level calculated by the predicted water level calculation unit 12, a quantitative judgment is made using the rules of the knowledge base 18, and an increase or decrease in the number of pumps in operation is determined. It is something to do.

On the other hand, the water level trend calculation part 4 manually calculates the pump well water level taken in through the process interface 9.
Based on this pump well water level, the time change in the water level, that is, the water level trend of the pump well 4 is calculated.

Furthermore, the empirical determination unit 15 performs an empirical determination using the rules of the knowledge base 18 based on the water level trend calculated by the water level trend calculation unit 14 and the pump well water level and rainfall amount taken in through the process interface 9. This will determine whether to increase or decrease the number of pumps in operation. Further, the comprehensive determination unit 16 determines based on the results of the quantitative determination by the quantitative determination unit 13 (increase or decrease in the number of pumps in operation) and the result of the empirical determination by the empirical determination unit 15 (increase or decrease in the number of pumps in operation). , performs comprehensive judgment and outputs a command to start or stop pump operation. Furthermore, the knowledge base 18 is either the experiential judgment knowledge of the operator regarding pump operation or the knowledge that has been summarized and stored as rules. It is now possible to enter the number of employees.

Next, the operation of the rainwater pump control device of this embodiment configured as described above will be explained using FIGS. 2 to 7.

In FIG. 1, first, the inflow flow rate calculation unit 11 calculates the inflow flow rate to the pump well 4 based on the pump well water level and the total discharge flow rate taken in through the process interface 9.

That is, the time is 1Δt, t-2Δt.

From the inflow flow rate calculation value of t-3Δ[, the estimated inflow flow rate Qi,(t) at time t is determined by the following autoregressive model.

Q. (t)-al・Q,. (t-Δt)+82 ・Q
;,, (t-2Δt) 10a3・Ql, (t-3Δt) ... (1) Q,,, (t) ・Estimated inflow flow rate Q at time t
1° (t-nΔt): Inflow flow rate calculation unit (n −1, 2, 3) at time t-nΔt, control period al, a2. a3: Autoregressive model parameter Further, the predicted water level calculation unit 12 predicts the water level of the pump well 4 a predetermined time ahead based on the pump well water level and the total discharge flow rate taken in through the process interface 9.

That is, the predicted water level after 61 seconds upper limit L□, (1+ΔT), lower limit L-,. (t+ΔT) is determined by the following equation.

L , , (t+ΔT) = f'(L , (L), Q :n(t), Q a+n
(t), ΔT)L, , , (t+ΔT) = r(L , (t), Q , , (t), Q , , (
t), ΔT)... (3) L, (t): Actual measured value of pump well water level Q at time t, (t): Upper limit Q of controllable range of pump total discharge flow rate at time t. , ゎ(t): Lower limit of pump total discharge flow rate controllable range at time t f: Water level prediction function Next, the quantitative determination unit 13 uses the inflow flow rate and predicted water level calculated in this way to calculate the following: The number of pumps in operation can be increased or decreased using methods such as the following.

That is, assuming that the current estimated inflow flow rate is constant over the predicted time and that there is no increase/decrease in the number of vehicles, the water level will be within the range of the predicted water level lower limit L□1o to the upper limit L□8.

Therefore, this L□at+Lmln is compared with the operation/stop water level for the number of pumps currently in operation, and L. If 1o is above the operating water level, it is determined that additional activation is required. However, L
m: If n is below the operating water level and L, , 8 is above the operating water level, it cannot necessarily be determined whether additional activation is necessary.

On the other hand, compare the estimated inflow flow rate with the pump total discharge flow rate controllable range upper limit Q□at and lower limit Qa+In,
If the estimated inflow flow rate is greater than Ql, 8, the water level is increasing, and Q m l. If it is smaller than , there is a decreasing trend. Therefore, if "the water level is on an increasing trend" is taken into consideration as a determination condition, it is considered appropriate to determine that additional activation is required.

In this way, a knowledge base based on water level and inflow flow rate18
By constructing a system, quantitative judgments can be made in the sense of calculating the water level and inflow flow rate through numerical calculations.

Next, in the empirical determination unit 15, the water level trend calculation unit 14
Based on the calculated water level trend, pump well water level, and rainfall amount, the following method is used to determine whether to increase or decrease the number of pumps in operation.

In other words, the factors that determine whether to start or stop the pump based on the operator's experience are: - The current water level is close to the upper or lower limit; - The trend of the water level is rising or falling; and - The amount of rainfall.

Therefore, ・Water level ・Water level trend ・Rainfall intensity Build a rule base for the following three judgment items.

For example, as shown in Figure 2, the water level is set at 0% as the stop water level for the number of pumps currently in operation, and as the starting water level for the next pump at 10%.
It is divided into 7 levels: bulky, high, slightly high, medium, slightly low, low, and low-low.

Similarly, the water level trend is divided into six stages as shown in Figure 3: steep rise, upper, slightly higher, slightly lower, lower, and lower, and the rainfall intensity is divided into 6 stages as shown in Figure 4: heavy rain, medium rain, It is divided into three stages: rain and light rain.

In addition, the operator's empirical judgment based on water level, water level trend, and rainfall intensity is basically based on the following ideas.

■If the water level is higher than the next unit starting water level, it will start regardless of the water level trend or rainfall intensity.

■If the water level is below the water level or the stop water level, the water level trend,
It will be suspended regardless of the intensity of rainfall.

■During heavy rain, depending on the water level and water level trend, start the system early and wait until the last minute before stopping.

■Start earlier and stop later in the order of heavy rain - medium rain - light rain.

■If it cannot be determined empirically, follow quantitative determination.

Taking the above five things into consideration, an empirical judgment table can be created. This table can be changed according to the aircraft location.

here, Increase: 1-layer Pon unit increase Decrease: Pump decrease by 11 Maintenance: Maintain the status quo Responsibility: Follow quantitative judgment shall be.

Next, the empirical determination is performed using a rule as shown in FIG. 5, for example, and inference is made in a 1f-then format.

For example, if the rainfall intensity is heavy, the water level trend is medium-high, and the water valve level is medium, then increase the number of pumps in operation.

In this way, if judgments can be described using an expert system, rules can be easily added or modified.

Next, as shown in FIG. 6, the comprehensive judgment unit 16 makes a comprehensive judgment based on the quantitative judgment result by the quantitative judgment unit 13 and the empirical judgment result by the empirical judgment unit 15. A command to start or stop pump operation is output. In addition, in this comprehensive judgment, in order to realize prompt drainage, if the results of each judgment are different, the rule is to give priority to the increase judgment.

FIGS. 7(a) to 7(d) are diagrams showing the difference between the control by the rainwater pump control device of this embodiment and the control by the conventional method by simulation. In Figure 7,
In the control by the rainwater pump control device of this embodiment, the pump is turned on early in response to a sudden inflow of rainwater, and the water level is suppressed to a level far lower than the warning water level (-dangerous water level).

As described above, the rainwater pump control device of this embodiment includes a pump well water level meter that detects the water level of the pump well 4, and a discharge flow meter 8 that detects the total discharge flow rate of the pump groups 5-1 to 5-n. , the pump well water level gauge 7, the discharge a flow meter 8, and the ground rain gauge 0, respectively, and the process interface 9
Input the pump well water level, total discharge flow rate, and rainfall taken in through the pump well water level, total discharge flow rate,
The inflow flow rate calculation unit 11 calculates the inflow flow rate to the pump well 4 based on the amount of rainfall and the amount of water, and the pump well water level and total discharge flow rate taken in through the process interface 9 are input, and the pump well water level and total discharge flow rate are calculated. Based on the predicted water level calculation unit 12 that predicts the water level of the pump well 4 a predetermined time ahead based on the inflow flow rate calculated by the inflow flow rate calculation unit 11, and the predicted water level calculated by the predicted water level calculation unit 12. , a quantitative determination unit 13 that makes a quantitative determination using the rules of the intelligence base 18 and determines an increase or decrease in the number of pumps in operation, and a pump well water level taken in through the process interface 9 as input, and based on this pump well water level. , a knowledge base 18 based on the water level trend calculation unit 14 that calculates the water level trend of the pump well 4, the water level trend calculated by the water level trend calculation unit 14, and the water level pump well and rainfall amount taken in through the process interface 9. The results of the quantitative determination by the empirical determination unit 15, which determines the increase or decrease in the number of pumps in operation by making an empirical determination using the rules of the quantitative determination unit 13, and the results of the empirical determination by the empirical determination unit 15. A comprehensive judgment unit 16 makes a comprehensive judgment based on the above and outputs a command to start or stop pump operation, and the operator's experiential judgment knowledge regarding pump operation is stored in advance as rules. It is composed of 18 knowledge bases.

Therefore, the increase or decrease in the number of pumps in operation is determined by adding the operator's empirical judgment to numerically backed quantitative judgment.In other words, the increase or decrease in the number of pumps in operation is determined by considering the water level trend of pump well 4. Therefore, it is possible to automatically control the number of pumps by reflecting the operator's empirical judgment, that is, by controlling the number of pumps close to the operator's actual experience regarding pump start/stop timing. This eliminates the need for operators to intervene manually due to concerns about the automatic operation of the pump, as was the case in the past, and the reliability of automated rainwater drainage pump control can be significantly improved.

In the above embodiment, the empirical determination unit 15 calculates the water level trend calculated by the water level trend calculation unit 14,
Although we have described a case in which an increase or decrease in the number of pumps in operation is determined based on empirical judgment based on the water level of the pump well and the amount of rainfall, this is not the only case. It is also possible to make an empirical judgment based on the water level and decide whether to increase or decrease the number of pumps in operation.

Further, in the above embodiment, the empirical determination unit 15 makes an empirical determination based on the water level trend calculated by the water level trend calculation unit 14, the pump well water level, and the amount of rainfall, and increases or decreases the number of operating pumps. This is not limited to the case where the water level trend calculated by the water level trend calculation unit 14, the pump well water level, the amount of rainfall,
In addition to these, the type of pump (e.g. pump capacity,
(fixed-speed pumps, variable-speed pumps, etc.) and the operating status of the pumps (e.g., pumps are available for use, pumps are out of service due to maintenance, etc.) to determine whether to increase or decrease the number of pumps in operation. It is okay to do so.

[Effects of the Invention] As explained above, according to the present invention, a comprehensive determination is made based on the increase/decrease in the number of pumps in operation determined by quantitative determination and the increase/decrease in the number of pumps in operation determined by empirical determination. Since the start or stop of pump operation is controlled, the number of pumps can be automatically controlled based on the operator's intuition, reflecting the operator's empirical judgment, making it extremely reliable. A rainwater pump control device can be provided.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram showing an example of applying the rainwater pump control device according to the present invention to a rainwater drainage pump station, and Fig. 2 is a classification of pump well water levels used for empirical judgment of number control in the same example. Figure 3 is a diagram showing the classification of water level trends in the same example. Figure 4 is a diagram showing the classification of rainfall intensity in the same example. Figure 5 is the basis of the knowledge base in the example. A diagram showing an example of the number control increase/decrease rule, FIG. 6 is a diagram showing an example of the knowledge base that is the basis for making a comprehensive judgment from quantitative judgment and empirical judgment in the same example, and Fig. 7 is an example of the operation in the same example. It is a simulation diagram for explaining the effect. 0 Ground rain gauge, 1...pipe culvert, 2...sand basin, 3...
...Screen, 4...Pump well, 5-1 to 5-n.
... Pump group, 6... River 7... Pump well water level meter, 8... Discharge flow meter, 9... Process interface, 10... Rainwater pump control device, 11... Inflow flow rate calculation Part, 12... Forecast water level calculation part, 13... Quantitative determination part, 14... Water level trend calculation part, 15...
Empirical judgment unit, 16... Comprehensive judgment unit, 17... Man-machine interface, 18... Knowledge Heas. Applicant's agent Patent attorney Takehiko Suzue Diagram △ Min diagram Diagram Rule table (heavy rain mode) Comprehensive judgment matrix

Claims (1)

[Scope of Claims] A number control device that is used in a pump facility that discharges rainwater flowing into a pump well into a river using a plurality of rainwater pumps, and that determines the timing of starting or stopping the pump group and an increase or decrease in the number of pumps in operation, Based on the water level and total discharge flow rate detected by a pump well water level meter provided in the pump well and a discharge flow meter provided on the discharge side of the pump group,
Predicting the water level of the pump well at a predetermined time point based on the water level and total discharge flow rate respectively detected by the pump well water level meter and the discharge flow meter; a predicted water level calculation means to calculate the predicted water level; and knowledge in which the operator's experiential judgment knowledge is stored as a rule based on the inflow flow rate calculated by the inflow flow rate calculation means and the predicted water level calculated by the predicted water level calculation means. a quantitative determination means for determining an increase or decrease in the number of pumps in operation by making a quantitative determination using a base rule, and based on the water level detected by the pump well water level meter,
a water level trend calculation means for calculating the water level trend of the pump well; and based on the water level trend calculated by the water level trend calculation means, the pump well water level, and the amount of rainfall if necessary,
an empirical determination means for determining an increase or decrease in the number of pumps in operation by making an empirical determination using the knowledge-based rules; and based on the quantitative determination result by the quantitative determination means and the empirical determination result by the empirical determination means. 1. A rainwater pump control device comprising: comprehensive determination means for making a comprehensive determination and outputting a command to start or stop pump operation.