Pipe network leakage prewarning method and system

Abstract

The invention discloses a pipe network leakage prewarning method and a system. The method comprises the steps of: obtaining daily minimum night flows MNFi and daily average flows Fi of water inlets of independent metering subareas; determining an average minimum night flow MNFi-6, i of MNFi within seven days on the ith day and an average minimum night flow MNF1, i of all MNFi up to the ith day; determining an average flow Fi-6, i of Fi within seven days at the ith day and an average flow F1, i of all Fi up to the ith day; calculating a difference value delta Fi of Fi-6, i subtracting F1, i and a difference value delta MNFi of MNFi-6, 1 subtracting MNF1, i; and judging if delta Fi and delta MNFi are both higher than a prewarning threshold, if so, generating prewarning information, and otherwise, giving no prewarning. The method and the system can accurately judge if newly added leakage points exist, so that the judging accuracy is improved.

Description

technical field [0001] The invention relates to the field of water supply pipe network leakage detection, in particular to a pipe network leakage early warning method and system. Background technique [0002] The leakage of the water supply pipe network wastes a lot of water resources, which has become a very serious social problem. In order to realize the efficient use of water resources, the leakage of the pipe network must be reduced. Among them, the first problem to be solved is the detection of the leakage of the pipe network. In the prior art, there are already some methods for detecting whether the pipe network is leaking, such as designing an independent metered area (DMA, district metered area), and continuously monitoring the flow of the DMA water inlet, generally set at every 15 minutes or longer Monitor a flow value at a time, know the real-time change process of the flow in the DMA, take the minimum night flow (MNF, minimal night flow) between one o’clock and fi...

AI Technical Summary

Problems solved by technology

Since the detection period of the flowmeter at the water inlet of the DMA is generally 15 minutes or longer, normal water is inevitably included in the MNF; at the same time, since the water pressure in the pipe network changes in real time, the number and size of the leakage points remain unchanged In some cases, the amount of water loss also changes in real time. Therefore, the fluctuation of normal water consumption and the fluctuation of water loss will cause the MNF to fluctuate up and down, which will reduce the accuracy of judging the abnormal change of flow rate, and then make the ability to identify the newly added loss point reduce

On the other hand, by using MNF time series data to judge whether a new leakage point occurs, a threshold needs to be determined. When the MNF exceeds this value, an early warning signal will be given. The threshold is usually set to add a Fixed value or fixed ratio, but this method of determining the threshold is highly subjective and lacks scientific basis, which further reduces the accuracy of judging the newly added missing points

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