JPH01113814A - Correcting method for measurement of level changing rate - Google Patents

Abstract

PURPOSE:To obtain the level changing rate data to the pump operation control by checking the fall/rise phenomena of a pump well level caused when the pump is started and stopped based on the change of the pump discharge amount to eliminate the level changes during said check and applying a smoothed arithmetic operation to obtain the level changing rate. CONSTITUTION:A transient period is checked for the pump discharge amount Q0 when the level of a pump well changes to the fall from the rise and vice versa. The level data on the transient period is deleted out of the level data for pump control. Then the changing rate of the level H is obtained is obtained at a sufficient time interval larger than the sampling cycle of the data input. Thus a smoothed continuous level changing rate is calculated and therefore the suited data is obtained to the pump control.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to measuring the rate of change in water level of a pump in a rainwater drainage pumping station, and in particular, accurately measures the rate of change in water level as the difference between inflow and discharge, which is basic data for pump control. Regarding how to correct measurements.

[Conventional technology]

Conventionally, regarding pump # water level drop/rise phenomena when the pump is started or stopped, transient phenomena are monitored for a certain period of time at the timing of pump start/stop, and the pump is controlled based on the subsequent water level change data, making it more accurate. In order to control the situation, it was necessary to allow sufficient monitoring time. In addition, related methods for avoiding the influence of disturbances such as partial water level vibrations or partial changes in water level are disclosed in Japanese Patent Application Laid-Open No. 62-8071.
No. 3 is mentioned.

[Problem that the invention seeks to solve]

However, with the above-mentioned conventional technology, when starting multiple pumps in succession, it takes a sufficient monitoring time of several minutes or more for the pump started first to reach its rated operation, resulting in poor start-up characteristics of the discharge amount. There was a problem that pump operation could not keep up with the sudden increase in the amount of rainwater flowing in after the onset of rain. Also,
If the monitoring time is shortened, there is a problem that water level changes include errors and the accuracy of pump control deteriorates. Therefore, the setting of this monitoring time is important and must be adjusted according to the characteristics of each individual pump.

An object of the present invention is to determine this monitoring time based on changes in pump discharge amount and pump #water level, and to measure and correct the water level change rate suitable for pump control, excluding water level fluctuations during this transitional period.

[Means for solving problems]

The above purpose is to reduce the pump #water level drop when starting and stopping the pump.
This is achieved by verifying the rising phenomenon by the change in the pump discharge amount, excluding the water level change during this period, and further calculating the rate of water level change by smoothing.

[Effect]

Pump # When the water level switches from rising to falling or from falling to rising, the transition period of the pump discharge amount is verified, and the water level data for this transition period is deleted from the water level data for pump control. Then, by determining the water level change rate at sufficient time intervals equal to or longer than the data input sampling period, the water level change rate is measured as a smoothed and continuous water level change rate, so data suitable for pump control can be provided.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. The purpose of the water level change rate calculation device 1 according to the present invention is to collect rainwater during rainfall into a pipe and drain it using a pump in order to prevent flooding. At the rainwater drainage pumping station 2, the pump #water level 3 and pump discharge amount 4 are inputted at fixed time intervals via the process data input/calculation device 6, and the pump #3 is input in chronological order.
Stored in the water level file 7 and pump discharge amount file 5,
For the pump #water level file 7, a water level sampling verification process 11 is performed to create a water level sampling file 12 in which the effects of temporary water level fluctuations at the time of starting and stopping the large capacity pump are removed. At this time, the pump operation signal 5 is taken in to detect the timing of temporary water level fluctuations when the pump starts and stops, and the event detection process 9 captures the timing of the pump start and stop. Timer monitoring process 10 Event detection process 9 generates an interlock signal for a preset monitoring timer time when an event is detected. The water level sampling verification process 11 executes water level sampling verification processing while this interlock signal is being generated. Next, the water level change rate smoothing calculation process 13 performs a water level change rate smoothing process on the water level sampling file 12 at regular intervals to create a water level change rate smoothing file 14 and provide the data to the pump control device 15. . The relationship between the inflow amount Q and the pump discharge amount Qo at a rainwater drainage pump station is (1
), the inflow amount Q due to the equipment structure of the rainwater drainage pump station
Since s cannot be measured, the pump control that controls the pump discharge amount Qo by following the fluctuation of the inflow amount Q1 is based on the water level change rate ΔH.
This can be achieved by accurately measuring /Δt.

Q s −Q o = A (H) ・ΔH/ΔT
-(1) Here, Ql: Inflow amount Qo: Pump discharge amount A (H): Pump #・Sand basin area ΔH/Δt: Pump #Water level change rate H: Pump #Water level Figure 2 shows the pump in Figure 1. # Processing details of the water level sampling verification process 11 that verifies the timing of the pump discharge amount file 8 that removes water level fluctuations at the time of pump start/stop and the timer monitoring process 10 against the water level file 7 to obtain the water level sampling deal 12 shows. Figure 2 (,)
Pump #water level H before treatment is directly affected by pump operation near the measurement location, and when the pump starts, the water level due to the vortex around the suction port may be pulled by the water suction of the pump and drop temporarily; When the pump is stopped, the water level may rise temporarily due to the elimination of the vortex.

When starting and stopping the pump, the timer monitoring process 10 controls execution and termination of the transient phenomenon test deletion process of the water level sampling test process 11 for a predetermined monitoring timer time T. In this process, when the pump #water level H switches from rising to falling or from falling to rising, pump discharge amount Q
o, and if the absolute value of the discharge rate change rate ΔQo/Δt is large within the range of the upper limit Qo and the lower limit QL, the data storage in the water level sampling file 12 is stopped as a transition period Tz, and the result is As shown after the processing in FIG. 2(b), a file 12 is created using the sampling water level H' for detecting the water level change rate.

Therefore, the pump #water level H6 at time to is removed from the water level sampling file 12.

Then, as shown in FIG. 3, a water level change rate smoothing file 14 is created from the water level sampling file 12 by a water level change rate smoothing calculation process 13. Pump #water level H' for which transient phenomenon has been verified is filed at time intervals of sampling period τ. By setting a sufficient time width ΔT for detecting the water level change rate and calculating the sampling period τ, accurate measurement is possible without time delay, as shown in Figure 3 (a).
As shown in the case of smoothing calculation processing, the water level change rate is smoothed to take a continuous value, so it becomes good data for pump control. FIG. 2(b) is a graph of arithmetic processing using non-smoothing sampling τ when the water level change rate is determined in the time width of the sampling period τ, which is not preferable as control data because it fluctuates greatly over time. Also,
By adding this smoothing process, it is possible to absorb the wave motion of the pump # during pump operation, so the data becomes data for realizing stable pump control.

〔Effect of the invention〕

According to the present invention, the rate of change in water level can be accurately measured as the difference between the amount of rainwater inflow and the amount of pump discharge, taking into account the water level drop phenomenon at the start of pump operation, so it is suitable for pump operation control. water level change rate data can be provided.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is an explanatory diagram of water level sampling verification processing, and FIG. 3 is an explanatory diagram of water level change rate smoothing calculation processing. DESCRIPTION OF SYMBOLS 1...Water level change rate calculating device, 2...Rainwater drainage pump station, 3...Pump #water level gauge, 4...Pump discharge amount needle, 5...Pump operation signal, 6...Process Data input/calculation device, 7... Pump #water level file, 8...
・Pump discharge amount file, 9...Event detection processing,
10...Timer monitoring process, 11...Water level sampling verification process, 12...Water level sampling file,
13...Water level change rate smoothing calculation process, 14...Water level change rate smoothing file, 15...Pump control device. , Agent Patent attorney Katsuma Ogawa High School 3rd figure 1z Bo ° (bJIL name Junzan Su) Prubute LSR Roshi Funujinsu 1 person.

Claims (1)

[Claims] 1. In a water level change rate calculation device consisting of a data calculation processing mechanism and a process data file at a rainwater drainage pump station, the phenomenon of water level drop and rise at the start and stop of pump operation is verified by changes in pump discharge amount, and hop control is performed. A water level sampling verification process is provided to delete the relevant abnormal data from the water level data, extract only the water level fluctuation data necessary for pump control, smooth the water level change rate at the input sampling period of the process data, and calculate the data for pump control. A water level change rate measurement correction method characterized by creating a water level change rate data file with minimal error.