JPS5837240A - Flow control device in water distribution reservoir - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] This invention relates to a flow rate joint system in water distribution reservoirs such as water and sewage systems. The present invention relates to a flow rate adjustment method for

Conventionally, this type of flow rate Section II method has been known as a method in which when the water level of reservoir 1 exceeds the upper and lower allowable limits, the inflow flow to the reservoir is shut off and the outflow flow from reservoir 1 or reservoir is shut off. However, this has the following drawbacks:

(1) II Sudden shutoff may cause large fluctuations in water pressure (this fluctuation in water pressure extends to other bonding processes and has a considerable influence).

B) One cutoff control may be activated due to a relatively instantaneous flow rate difference between one inflow and one outflow, resulting in the phenomenon (1) above.

This invention was made in order to eliminate the drawbacks of the conventional system as described above, and therefore, the purpose of this invention is to avoid sudden changes in the inflow and outflow flow rates and to avoid instantaneous inflow and outflow flow differences. The purpose of the present invention is to provide a flow rate adjustment method in a water distribution reservoir that does not cut off the inflow or outflow even if the inflow or outflow is interrupted, but can absorb it by slightly adjusting the flow rate. When adjusting the flow rate to control the water level in a distribution reservoir, if the water level exceeds the upper limit and is about to rise further, or if it is about to fall further below the lower limit, the By creating a target value based on certain rules, taking into account the actual water level, inflow amount, outflow amount, etc. at that time, and setting it in the flow controller, it is possible to maintain the specified value without causing sudden fluctuations in flow rate. The key point is that it makes it possible to control the water level.

Next, the present invention will be described in detail with reference to the drawings.

First, in the present invention, when the water level of the water distribution reservoir reaches around IJtt, a characteristic curve indicating the maximum allowable flow rate corresponding to the water level 11f(H) is determined in advance, and the allowable flow rate range is previously set in accordance with the water level using this curve. This relationship is shown in FIG.

FIG. 1 is a graph showing limit tune II (upper limit monitoring limit tune 1 [) representing the limit of the allowable inflow flow rate with respect to the water level. In the figure, K is the upper limit monitoring limit curve. The vertical axis represents the inflow flow rate Q, and the horizontal axis represents the water level H. The area below the limit song IIIK (the 8M area in the figure) shows the allowable flow rate range corresponding to the water level.

For example, in FIG. 1, when the water level is Hl, it is shown that a flow rate exceeding Ql must not be allowed to flow as the inflow flow rate. This limit song! IK has properties that are required in light of the intended purpose, depending on the characteristics of the water distribution reservoir.

[Figure 2 is a system configuration diagram showing an embodiment of the invention. In the figure, water flows into the water distribution reservoir 7 from an inflow pipe 8 and is distributed to consumers from an outflow pipe 9.

In j12WJ, upper ** viewing device 4, flow rate controller 1,
The water level in the distribution reservoir 7 is monitored and controlled so as not to exceed the upper limit by the flow control valve 3, the flow rate needle 2, and the water level needle 6, and the lower limit monitoring device 4A, the flow rate controller IA, the flow rate $2A, and the water level meter are used. 6 monitors and controls the water level of the water distribution reservoir 7 so that it does not exceed the lower limit. Note that 5 is a flow rate target value setting device.

The above S monitoring control will be explained. The upper WA monitoring device 4 stores an upper limit monitoring kit curve K shown in the first wJ.

Currently, a setting device (generally a computer is used, but
When the flow rate target value is given from (not limited to this) 5), the upper limit monitoring device 4) calculates the allowable maximum value from the water level H at that point given from water level ti6 and the stored upper limit monitoring IJ 41. Determine the flow rate ◇If the target flow rate given from the setting device 5 is within the range of the maximum allowable flow rate, it is output as is to the controller 1 as the target value.

If the allowable maximum flow rate is exceeded, the target value given from the setting device 5 is automatically compressed and changed to the allowable maximum flow rate value, and then provided to the controller 1. Due to the action of the upper limit monitoring device 4, sudden rises and falls in the water level near IJ due to the instantaneous flow rate difference between the inflow and outflow to the water distribution reservoir 7 are avoided, and the stability of the water distribution process is maintained. The regulator 1 compares the target value given via the upper limit monitoring device 4 with the actual flow rate value given from the flow meter 2, and adjusts the flow rate regulating valve 3 so that the difference becomes zero. It goes without saying that it is a thing.

Next, lower limit monitoring control will be explained. Lower limit monitoring device 14
A stores the lower limit monitoring IJ J) curve u shown in 3rd g (note that K is also shown at 113 m because of the relative positional relationship between the 1 lower limit monitoring limit song 11u and the upper limit monitoring limit song IIK). (This is to gain understanding.) As before, when the flow rate target value is given from the setting device 5, the water level H given from the water level gauge 6 at that point is
The maximum allowable flow rate is determined from the stored lower limit monitoring limit song 11u. If the flow rate target value given from the setting device 5 is within the range of the allowable maximum flow rate, it is output as is to the controller IA as the target value, but if it is outside the range, the compression 1 is changed to the allowable maximum flow value. 1m11t1 total I
Give to A. The effect is the same as in the case of upper limit monitoring 1IlIll.

The embodiment shown in the second wI was an example in which the upper limit monitoring control of the 1st water level was carried out at node 11 of the inflow flow rate, and the lower limit monitoring control was carried out by adjusting the outflow flow rate.
As shown in Figure 1, the upper and lower limits are monitored and controlled at 11 of the inflow flow rate.
It can also be implemented by doing it in sections.

111411. In the figure, IO is an upper and lower limit monitoring device, and 11 is a pump. Upper and lower limit monitoring device 1
A song that monitors the upper and lower limits to 0! I[[It's fine if you're afraid, but the action itself is the same as what was explained in 1112m.

The fifth wI is a system configuration diagram showing still another embodiment of the present invention. In the embodiment shown in the figure, the upper and lower limit monitoring device 1
0, the inflow flow rate measured by the flow meter 2, the outflow flow rate measured by the two flow meters, and the water level measured by the water level needle 6 are input, and upper and lower limit monitoring control is performed as follows.

First, the upper and lower limit monitoring device 10 newly stores a limit weight curve as shown in No. 6H, as in the case of the previous embodiment, and performs necessary correction calculations based on this curve. IJ (as shown in Figure 6, the weight curve consists of the upper limiter 1 weight dki* and the lower limit weight curve IIu, the horizontal axis represents the water level H, and the vertical axis represents the dimensionless 0 to 1001i.Explaining the upper limit curve K, this is the upper limit water level HK
01g between LiMiT and nearby water level HK
It is a curve that changes from to 100s, and is a function g of 1 water level H.
It can be expressed as (HK). Tsuyari Seki 11g (HK) is
This is the weight Rwk for the water level between the water level HK and the upper limit water level HKL i -T. The same is true for the lower limit curve U, 1rR'llt g (Hu)
are the lower limit water level H, and the lower water level HuLj.
This is the weight interval for the water level between Mi'l' and i'.

Upper limit monitoring control will be explained first. The conditions for upper limit monitoring control are (inflow flow rate) > (outflow flow rate) and (water level)
>HK. When these two conditions are satisfied, the device 10 stores the upper limit weight 14I (HK
) to perform the following correction calculation to obtain the corrected flow rate f' (H
).

The sum of the amounts is set as a new flow rate target value in the I1 metering weight. The water level is the upper limit water level HKL! Assuming the point when MjT is reached, since g(Hx)=100, it represents the outflow flow rate, and since the inflow flow rate and the outflow flow rate match, it is calculated that the water level will not rise any further.

The conditions for performing the lower limit monitoring control are: - (inflow flow rate) - outflow flow rate, and (water level) < Hu. The rest is the same as in the upper limit monitoring control described above, so no further explanation will be provided. It goes without saying that the limit weight curve is determined in such a way as to obtain the optimum one in terms of performance, taking into account the capacity, surface area, etc. of each pond.

Further, when the conditions for performing monitoring control are not satisfied, the device 10 makes the set value from the flow rate target value setting device 5 valid and passes it to the weight controller 1.

In the embodiment shown in FIG. 5, upper and lower limit monitoring control is performed on the inflow side of the pond, but it is of course possible to perform this on the outflow side.

In the example of the 4th H, the amount of outflow was not monitored, so when the fluctuation in the amount of outflow was large, the control performance was insufficient, but in the example of FIG. Since the flow rate is also monitored, even if the fluctuation is large, the influence does not greatly affect the adjustment of the inflow flow rate, and the first adjustment operation is always good.

4th A[ is a graph showing the control results of the upper limit monitoring control in the embodiments of ~4th wA, where (a) shows the case where the flow rate is small and S (b)) shows the case where the flow rate is large. In Fig. 4A h), the water level started to rise further from point P, so we started the upper III monitoring control and changed the setting of the electric controller weight 1 to control the water intake, which had been constant until then, for a period R. This means that there are 11 verses. It can be seen that the water reception curve is relatively smooth and control is well performed compared to the case of flow holes shown in j14AwJ (b). Figure 4A (
In the case of (b), where the flow rate is a hole, if upper limit monitoring control is implemented in the same way, the water reception curve in period B will fluctuate greatly, and the control performance will not be as good as in case (a), where the flow rate is small. I can't say it.

The jlSA diagram is a graph showing the control results of the upper limit monitoring control in the embodiment of FIG. 5, where (a) shows the case where the flow rate is small, and (main) shows the case where the flow rate is large. In both (a) and (b), the fluctuation of the water receiving curve in period B is the 4th AIm
It is smoother than that in (b), and this point is particularly noticeable in the case of the flow hole (b).

It seems that the good control performance of the actual example of jl151iff has been understood.

As explained above, according to the present invention, sudden changes in the flow rate near the upper and lower limits of the water level in one distribution reservoir can be avoided, and the water level can be kept within the limit by relatively gentle flow rate correction, which is not possible in the conventional method. This has the advantage that it is possible to avoid problems that may cause large horizontal fluctuations and adversely affect other bonding processes.

This invention is applicable to all water accesses, such as water distribution reservoirs, that have inflows and outflows.

For example, water supply, sewerage process reservoirs, etc.

[Brief explanation of the drawing]

1st IW is a graph showing an upper limit monitoring limit curve representing the limit of allowable inflow flow rate with respect to water level, Fig. 2 is a system configuration diagram showing an embodiment of the present invention, and Fig. 3 is a lower limit and upper limit monitoring limit curve. 4 is a system configuration diagram showing another embodiment of the present invention, and 4th Ag is *
A graph showing the control results of the upper limit monitoring control in the embodiment of 4WJ, and FIG. 5 is a system configuration diagram showing yet another embodiment of the present invention. The graph No. 6N is a graph showing a limit weighting curve for the pressure accumulation calculation performed in the fifth wI embodiment. Symbol explanation 1...Flow rate controller, 2...Flow rate needle,
3...Flow control valve, 4...Upper (lower) I
I monitoring device, 5...Flow rate target value setting device, 6.
...Water level needle, 7...Water reservoir, 8...
...Inflow pipe, 9...Outflow pipe, lO...
...Upper/lower limit monitoring device, 11... Pump agent Patent attorney Akio Namiki Attorney Patent attorney Kiyoshi Matsuzaki Figure 4A-1!4Itl Temporary m 15All -phase-apr*

Claims (1)

[Claims] 1) An 11-point flow rate needle for adjusting the inflow and/or outflow to the water distribution reservoir, and a predetermined tolerance for the inflow and/or outflow with respect to the water level in the water distribution reservoir. It consists of a water level limit monitoring device that stores a range limit, and a flow rate target value setting device that outputs a flow rate target value for the flow rate adjustment needle, and the monitoring device reads the flow rate target value outputted from the setting device. Check whether the actual water level of the distribution reservoir at that time and the inflow flow rate and/or outflow flow rate are within the allowable am. A flow rate adjustment method in a water distribution reservoir characterized in that when the adjustment needle is set to a value outside the permissible range, the value is changed to the permissible @ pronation value and then set. 2) A flow rate controller to adjust the inflow (or outflow) to the water distribution reservoir, and a correction calculation for monitoring the inflow, outflow, and water level in the water distribution reservoir and keeping the water level within a predetermined range. A water level limit monitoring device that stores a weighting coefficient of 1, and a flow rate target value setting device that outputs a flow rate target value for the flow rate intermittent needle. Set the value as is to the flow rate adjustment needle as it is, and when the water level rises above a certain limit and the inflow exceeds the outflow, or the water level falls below a certain limit and the inflow falls below the outflow. When the flow rate is reached, a new flow rate target value is determined from the pressure flow rate calculated by multiplying the difference between the outflow rate and the inflow rate by the weighting coefficient that is stored, and the inflow rate (inflow or outflow rate) at that time. A flow rate adjustment method in a water distribution reservoir characterized by reducing fluctuations in flow rate by setting a flow rate adjustment needle.