Design method for performing PMA partition optimization and DMA partition optimization synchronously on water supply network

Abstract

The invention discloses a design method for carrying out PMA partition optimization and DMA partition optimization synchronously on a water supply pipe network. The design method comprises the following steps: firstly, simulating a daily pipe network operation state by a hydraulic model; generating a pipe network topographic map in combination with the ground elevation, and preliminarily determining a partition structure by determining the maximum value range of the ground elevation difference; calculating the shortest path from any node of the pipe network to the central point of the pressure point of each partition to obtain a new partition structure; the pressure center point of the new partition structure is recalculated, and a partition scheme is obtained through optimization calculation and special point adjustment; on the basis of the determined PMA scheme, the range is further narrowed to refine the DMA scheme, and DMA partitions are determined by adopting the same algorithm and adjustment mode; and a DIJKSTRA algorithm is adopted, and the positions of partition flow monitoring equipment, a pressure control device and a valve are determined. And a plurality of evaluation indexes are calculated through hydraulic simulation to determine an optimal PMA and DMA overall partitioning scheme. And carrying out transverse comparison on the optimized PMA partition scheme by utilizing a pipe network energy surplus ratio, sorting the PMA partitions, and determining the priority of pressure management.

Description

Technical Field

[0001] The invention relates to the field of water supply network design, and in particular to a design method for optimizing PMA partitions of a water supply network and simultaneously optimizing DMA partitions. Background Art

[0002] As an important part of the urban water supply system, the water supply network is the link between users and water resources. Pipeline leakage is still a key concern of the water supply system and an urgent problem to be solved. Although the leakage of the pipeline network has shown a downward trend year by year, there is still a significant gap from the expected target, especially in areas with poor urban planning. Pipeline leakage management is still in the exploratory and initial stages. There are mainly problems such as lack of systematic leakage management solutions, unclear zoning metering solutions, and fragmented information engineering.

[0003] Zoning metering is a refined management model for quantifying water supply network leakage zones and effectively controlling leakage. Zoning management can quantify the spatial distribution of leakage water, which is conducive to the implementation of targeted leakage control measures.

[0004] At present, there are three main modes of zoning metering management technology, namely independent metering area (DMA), pressure zone (PMA) and management zone (MA). The primary task of zoning metering management is the design of the zoning scheme. However, in the actual zoning scheme design process, since DMA zones have entrances and exits, but pressure zones generally adopt a single area entrance and a closed perimeter, it is difficult to comprehensively consider pressure zones on the basis of optimizing DMA zones. Summary of the invention

[0005] In order to solve the technical problems that the leakage of the current water supply network is high and it is difficult to comprehensively consider the metering and pressure in the zoning management, the present invention proposes a design method for PMA zoning optimization of the water supply network and simultaneous DMA zoning optimization.

[0006] In order to achieve the above technical purpose, the technical solution of the present invention is:

[0007] A design method for optimizing the PMA partition of a water supply network and simultaneously optimizing the DMA partition includes the following steps:

[0008] Step 1: Establish a hydraulic model of the water supply network for simulating the daily operation status of the network and calibrate it according to the monitoring data;

[0009] Step 2: Generate a topographic map of the water supply network based on the ground elevation data of the network, and then set the maximum allowable height difference Δh for the terrain height difference used for zoning based on the topographic map. max , and the terrain height difference Δh around the pipe network is set at Δh maxThe pipe network within the range is classified into a zone, thus initially forming a PMA zone; then the average pressure of each PMA zone is calculated and find the The closest pipe network node is used as the pressure center point of this PMA zone;

[0010] Step 3: Count the shortest paths between all nodes and the pressure center of each PMA partition, and then calculate the weight according to the pressure and the shortest path. Finally, adjust all nodes that are not divided into the PMA partition where the pressure center with the smallest weight is located to the corresponding PMA partition.

[0011] Step 4: recalculate the average pressure of the partition obtained in step 3, find the pressure center point of the new partition again, and then return to step 3 and re-execute until the repetition of the nodes contained in the previous and next partitions reaches a preset threshold. When the repetition is greater than the threshold, re-execute the partition before step 3 and record it as an alternative solution.

[0012] Step 5: Based on the PMA partition obtained in step 4, reduce Δh max value to repeat step 2, so as to form multiple DMA partitions with smaller ranges in the PMA partition, and then calculate the average pressure of each DMA partition again, and find the pressure center point closest to the average pressure of the DMA partition, and perform the same process as steps 3-4 to optimize the DMA partition;

[0013] Step 6: Determine the flow monitoring equipment, pressure control device and valve location according to the partition:

[0014] For PMA zones: Calculate the water supply path weight ω from the water source point to the zone pressure center point H1 ω H1 The smallest pipe section is used as the main water supply path; flow monitoring equipment is set on the pipe section of the shortest water supply path and pressure control equipment is reserved. If, when calculating the main water supply path, the pressure center points of different PMA partitions share a water supply path, all PMA partitions sharing the water supply path are merged into a large PMA partition, and steps 3-4 are repeated to optimize the PMA partitions to form new PMA partitions; then the energy loss path weight ω of the boundary pipe section from the water source point to the PMA partition is calculated. E1 , in ω E1 Add valves to the smallest pipeline that has the least number of passes from the water source point to the boundary section of the PMA zone;

[0015] For DMA partitioning: Use and calculate ω H1 The same method is used to calculate the water supply path weight ω of the pipe section from the water source to the pressure center point of the DMA partition. H2 , and then use and calculate ω E1The energy loss path weight ω on the boundary pipe segment of the DMA partition structure is calculated in the same way E2 ; Weight of water supply path ω H2 Add flow monitoring equipment to the smallest pipeline, and set the energy loss weight ω E2 Add valves to the least number of pipelines; if the DMA partition boundary coincides with the PMA partition boundary to which it belongs, select ω E1 In small pipelines, valves are installed in the pipelines with the least number of passes from the water source point to the boundary pipe section of the PMA zone;

[0016] Step 7: Use the hydraulic model to calculate the evaluation indicators of the PMA partition and the DMA partition and their respective alternatives. The evaluation indicators include the pressure balance of the pipe network PEC, the number of nodes that meet the water quality requirements U mq and the cost of the pipe network zoning renovation project C;

[0017] Step 8: Under the premise of ensuring the most balanced pressure and the largest number of nodes that meet the water quality requirements in the zone, select the zone with the lowest zone renovation project cost as the final PMA and DMA zone plan;

[0018] Step 9: Calculate the network energy surplus ratio E for each PMA partition in the final PMA partition scheme. sr , so according to E sr The size of the pressure is used to determine the priority of stress management. sr Larger PMA partitions.

[0019] In the design method, in step 2, the average pressure is calculated by the following formula:

[0020]

[0021] in, is the average pressure of a PMA partition, P i is the pressure of any node i in the pipeline network, and n is the total number of corresponding nodes in the PMA partition.

[0022] In the design method, in step 3, the function formula of the weight is:

[0023]

[0024] Among them, ω is the weight coefficient, and l is the pipe length from any node to the pressure center.

[0025] The design method, after the step 3 is executed, further comprises the following steps:

[0026] When all the surrounding nodes of a certain node are in the same PMA partition, but the node is divided into other PMA partitions, the node is re-divided into the same PMA partition as the surrounding nodes.

[0027] In the design method, in step 4, the threshold of repeatability is 95%-100%.

[0028] In the design method, in step 6,

[0029] Weight of main water supply path ω H1 The smaller it is, the more important the pipe section is in the water supply network. The calculation formula is as follows:

[0030]

[0031] Among them, ω H1 is the water supply path weight of pipe segment k; l k is the length of pipe section k; q k is the flow rate of pipe section k; d is the diameter of pipe section k;

[0032] The energy loss weight ω E1 represents energy consumption, ω E1 The smaller it is, the less important the pipeline is. The calculation formula is as follows:

[0033]

[0034] Among them, ω E1 is the energy loss path weight of pipe segment k; γ is the density of water; s k is the friction coefficient of pipe section k; m is the flow index, the value of the water supply and distribution pipeline and water distribution network adjustment is 1.852, and the value of the water supply pipeline is 2.

[0035] In the design method, in step 7, the calculation process of the pipe network pressure equalization PEC includes:

[0036] The network pressure balance PEC is used to indicate the degree of dispersion of the node pressure of the partition where the partition flow accounts for the weight of the entire water supply network flow and the average pressure of the partition. The smaller the value, the closer the node pressure is to the average pressure, indicating that the partition pressure is more balanced; the calculation formula is:

[0037]

[0038] Where M is the number of pipe network partitions, n is the total number of nodes contained in the mth partition; P i is the pressure of the ith node in the mth partition; is the average pressure of nodes in the mth partition, Q m is the sum of the water demand of the nodes in the mth partition, Q总 It is the total water consumption of the system.

[0039] In the design method, in step 7, the pipe network zoning reconstruction project cost C is calculated by the following formula:

[0040]

[0041] in, Cost of purchasing the nth flow equipment; Installation costs for the nth flow device; The purchase cost of the nth valve; Installation cost for the nth valve; The cost of purchasing the nth pressure control device; Installation cost for the nth pressure control device; K f is the total number of flow devices; K v is the total number of valves; K p is the total number of pressure control devices.

[0042] The design method, in step 7, the number of nodes that meet the water quality requirements is U mq Calculated by the following formula:

[0043]

[0044] Among them, T i is the water age of the i-th node in the pipe network; T max U is the maximum water age allowed at the node when the free chlorine at the end of the pipe network meets the national water quality standards; j is the upstream node connected to node i; q ki is the pipe flow rate of pipe k connected to node i; T k is the water age of the upstream node connected to node i; t ki is the water flow time of pipe section ki; U mq is the total number of nodes where water quality meets water quality requirements. i ≤T max The value is 1, when T i >T max The value is 0.

[0045] In the design method, in step 9, the network energy surplus ratio E sr The calculation process includes:

[0046] Pipeline network energy surplus ratio E sr Indicates the size of the node's surplus energy. The larger the value, the larger the surplus voltage reduction space. The calculation formula is as follows:

[0047]

[0048] Among them, E1 is the surplus energy of nodes within each PMA partition; E e is the effective energy of nodes within each PMA partition; E t is the total node energy within each PMA partition; γ is the water density; Q i is the traffic volume of node i within the region; H min Minimum service head of the i-th node of the pipe network; H i is the actual service water head of node i; n is the total number of nodes in each PMA partition

[0049] The technical effect of the present invention is that the present invention comprehensively considers the PMA and DMA zoning schemes, performs PMA zoning in large areas, arranges DMA zoning reasonably, proposes a method of optimizing PMA zoning and DMA zoning simultaneously, takes into account the dual effects of pressure management and zoning management, and maximizes the advantages of different zoning modes. The present invention sets evaluation indicators such as pressure balance, the number of nodes that meet water quality requirements, the cost of zoning transformation projects, and the energy surplus ratio of the pipeline network, and performs scheme optimization comparison, which solves the problems that the zoning in the engineering design stage cannot guarantee the hydraulic performance of the zoning, cannot consider energy saving and energy consumption, cannot reduce the cost of zoning transformation projects, and improve the operating efficiency of the pipeline network system. The present invention adopts an intelligent algorithm to determine the flow monitoring equipment, pressure control device, and valve position, and determines the optimal zoning scheme according to the evaluation index, so that the zoning scheme is more scientific and reasonable, which is conducive to guiding engineering designers to determine the final zoning scheme. The present invention uses the DIJKSTRA algorithm for optimizing zoning and determining the equipment installation location. The algorithm is the most mature greedy heuristic strategy. The algorithm is simple in idea, relatively easy to use, suitable for a wide range of scenarios, and more conducive to application in actual engineering. The present invention adopts the pipeline network energy surplus ratio index to determine the pressure management priority in the final optimization plan, providing technical support for subsequent pressure management. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a schematic diagram of the process of the present invention. DETAILED DESCRIPTION

[0051] See also Figure 1 The present embodiment discloses a design method for optimizing PMA partitions of a water supply network and simultaneously optimizing DMA partitions. The general process includes:

[0052] First, the daily operation status of the pipeline network is simulated by the hydraulic model, and the data is checked and calibrated. Then, the GIS tool is used to generate a 3D topographic map of the pipeline network in combination with the ground elevation, and the PMA partition structure is preliminarily determined by determining the maximum range of the ground elevation difference. Next, the DIJKSTRA algorithm is used to calculate the shortest path from any node of the pipeline network to the center point of each partition pressure point based on the weight, and the belonging area of ​​individual points with higher service head is adjusted to obtain a new PMA partition structure. The pressure center point of the new PMA partition structure is recalculated, and the optimization calculation is repeated many times until the repetition rate requirements of the front and rear partition nodes are met. The PMA partition scheme is considered to be stable. On the basis of the stable PMA partition scheme, the partition range is further narrowed to form a DMA partition, and the DMA scheme is further refined. The DIJKSTRA algorithm and special point adjustment method are also used to determine the DMA partition. The DIJKSTRA algorithm is used again for the PMA and DMA partition schemes to determine the partition flow monitoring equipment, pressure control device and valve position. The optimal PMA and DMA overall partition scheme is determined based on multiple evaluation indicators calculated based on hydraulic simulation. For the optimized PMA zoning scheme, the network energy surplus ratio is used for horizontal comparison, and the PMA zones are sorted to determine the priority of pressure management.

[0053] Based on the above general process, this embodiment specifically includes the following steps:

[0054] 1. Establish a hydraulic model of the water supply network to hydraulically simulate the daily operation status of the network, and then calibrate the hydraulic model of the network by combining the data including pressure and flow monitored by the SCADA system.

[0055] 2.PMA preliminary zoning: obtain the ground elevation data of the pipeline network, use GIS tools to generate a 3D topographic map of the pipeline network, and set the maximum allowable height difference Δh of the terrain height difference in different areas based on the topographic map max In specific implementation, Δh max The following two methods can be considered: one is to determine it according to the water supply range of different water plants and pumping stations. The other is to divide it according to the high and low areas of the city terrain. For example, if there are mountains in the city, then the height difference is calculated by looking at the maximum and minimum ground elevations around the mountains as the Δh of this area. max If the terrain is relatively flat, check the maximum and minimum ground elevations, and use the difference between the two as Δh max These two forms are commonly used. In specific implementation, other methods that can achieve PMA partitioning can also be used to determine Δh max .

[0056] Control the terrain height difference Δh around the pipeline network within Δh max The pipe network in the area is classified into a PMA zone, thus initially forming a PMA zone. Then the average pressure of each PMA zone is calculated. And find the PMA partition with The closest pipe network node is taken as the pressure center point of the area.

[0057] Where: Average pressure calculation formula

[0058]

[0059] In the above formula, is the average pressure in the area, in MPa. i is the pressure of node i in the pipe network, calculated by the hydraulic model, in MPa. n is the total number of nodes in each partition, in units.

[0060] 3. Take the pressure center point of each partition as the end point, and the minimum pressure difference and pipe length between two nodes of the pipeline as the weight. Use the DIJKSTRA algorithm to calculate the shortest path weight value from any node in the pipeline network to each pressure center point, and adjust the node with the smallest weight from the pressure center point of each partition to the partition. Repeat this step for all nodes one by one until all nodes are traversed.

[0061] The weight function formula is as follows:

[0062]

[0063] Where ω is the weight coefficient, l is the pipe length from any node to the pressure center, in meters.

[0064] After the adjustment is completed, for individual points whose service head is significantly higher than the surrounding ones, fine-tuning should be performed and the belonging area should be determined according to the actual terrain characteristics and surrounding conditions, and finally a new partition structure is obtained. Specifically, when the surrounding nodes of a certain node are all in the same PMA partition, but this node is divided into other PMA partitions, this node will be re-divided into the same PMA partition as the surrounding nodes.

[0065] 4. Recalculate the average pressure for the new partition structure, find the pressure center point of the new partition again, and repeat step 3 until it is determined that the repetition of the nodes of the front and rear partitions is at a high level. In this embodiment, when the node repetition is set at ≥95%, the partition is considered stable, and the partition with the repetition of the nodes of the front and rear partitions ≥95% is used as an alternative scheme, which is used for the calculation and comparison of subsequent evaluation indicators.

[0066] 5. Form a refined DMA partition based on PMA: Reduce Δh based on the determined PMA solution maxvalue to further narrow the range, thereby forming multiple DMA partitions with smaller ranges in the PMA partition, and then calculating the average pressure of each DMA partition, and finding the closest pressure center point, and then refer to steps 3-4 to optimize the DMA partition.

[0067] 6. Determine the flow monitoring equipment, pressure control devices and valve locations for the zoning scheme, including the following two situations:

[0068] PMA zoning: The DIJKSTRA algorithm is used to calculate the main water supply path from the water source point to the pressure center point of the new zone. The pipe section with the smallest water supply path weight is used as the main water supply path, and a flow monitoring device is installed as the zone entrance. At the same time, a pressure control device is reserved to facilitate later pressure management. If, in the calculation of the water supply path weight, the pressure center points of multiple PMA zones share a main water supply path, that is, the same main water supply path passes through the pressure center points of more than one PMA zone, then multiple PMA zones are merged into a large PMA, and then steps 3-4 are repeated and the PMA is optimized to form a new PMA zone. Then the DIJKSTRA algorithm is used to calculate the path with the least energy loss weight from the water source point to the boundary pipe section of the PMA area, and valves are added to the pipeline with the smallest energy loss weight and the smallest number of passes in the boundary pipe section from the water source point to the PMA zone.

[0069] DMA zoning: The same method as PMA zoning is used to calculate the main water supply path from the water source to the pressure center point of the DMA zoning, calculate the path with the least energy loss weight on the boundary pipe section of the new refined zoning structure, add flow monitoring equipment on the shortest water supply path, and add valves to the pipeline on the path with the least energy loss. If the DMA zoning boundary coincides with part of the PMA zoning boundary, the valve should be set on the pipeline with the least number of passes from the water source point to the PMA zoning boundary in the path with the least energy loss in the PMA zoning.

[0070] In this embodiment, the water supply path weight ω H The smaller it is, the more important the pipe section is in the water supply network. The calculation formula is as follows:

[0071]

[0072] Among them, ω H is the water supply path weight of pipe segment k. k is the length of pipe section k, in meters. k is the flow rate of pipe section k, in m 3 / s. d is the diameter of pipe section k, in m.

[0073] The weight of the energy loss path ω EThe smaller the value, the smaller the energy consumption, which means the pipeline is less important and can be regarded as a redundant pipeline. Setting a valve on the pipeline can minimize the impact on the system after the valve is closed. The formula is as follows:

[0074]

[0075] Among them, ω E is the energy loss path weight of pipe segment k. γ is the density of water, unit is 9800N / m 3 .s k is the friction coefficient of pipe section k, in s 2 / m 5 m is the flow index, which is 1.852 in water distribution pipelines and water distribution networks, and 2 in water distribution pipelines.

[0076] 7. Combine the results of the hydraulic model to obtain the evaluation indicators of multiple zoning schemes, and use the hydraulic model to calculate the evaluation indicators of the preliminary zoning and multiple optimized zoning. The evaluation indicators include the pressure balance of the pipe network PEC, the number of nodes that meet the water quality requirements U mq and pipeline network zoning renovation project costs C.

[0077] The pipe network pressure balance PEC is used to indicate the degree of dispersion of the partition node pressure and the partition average pressure of the partition flow weighted by the entire system flow, that is, the sum of the pipe network partition node balance coefficients. The smaller the pressure balance coefficient, the closer the node pressure is to the average pressure, indicating that the partition pressure is more balanced. The formula is as follows:

[0078]

[0079] Where: M is the number of pipe network partitions, and n is the total number of nodes contained in the mth partition. i is the pressure of the ith node in the mth partition, in MPa. is the average pressure of the nodes in the mth partition, in MPa, Q m is the sum of the water demand of the nodes in the m partition, in L / s, Q 总 It is the total water consumption of the system, in L / s.

[0080] The cost of the pipeline zoning renovation project C is used to represent the engineering cost required for the zoning scheme renovation, and is an indicator for determining whether the engineering scheme design is economically reasonable. The formula is as follows:

[0081]

[0082] Among them: C is the cost of pipeline network zoning renovation project. It is the purchase cost of the nth flow equipment, in Yuan. It is the installation cost of the nth flow device, in Yuan. is the purchase cost of the nth valve, in Yuan. is the installation cost of the nth valve, in Yuan. is the purchase cost of the nth pressure control device, in Yuan. K is the installation cost of the nth pressure control device, in yuan. f is the total number of traffic devices. K v is the total number of valves. K p is the total number of pressure control devices.

[0083] The number of nodes that meet water quality requirements U mq It indicates the number of nodes that meet the water quality requirements after the pipe network is partitioned, which is an important basis for judging the changes in water quality after partitioning. The formula is as follows:

[0084]

[0085] Where: T i is the water age of the i-th node in the pipe network, in h. T max It is the maximum water age allowed at the node when the free chlorine at the end of the pipe network meets the national water quality standards, in h. j is the upstream node connected to node i. ki is the flow rate of pipe segment k connected to node i, in L / s. k is the water age of the upstream node connected to node i, in h. t ki U is the water flow time of pipe section ki, in h. mq is the total number of nodes where water quality meets water quality requirements. i ≤T max The value is 1, when T i >T max The value is 0.

[0086] 8. Taking into account the current status of the system, the operation and maintenance needs of the water company and the evaluation index results, the zone with the lowest zone renovation project cost is selected as the final PMA and DMA zone plan, while ensuring the most balanced pressure and the largest number of nodes that meet water quality requirements within the zone.

[0087] 9. Calculate the network energy surplus ratio E for each PMA partition in the determined zoning scheme sr , according to E sr The size of the pressure can be used to determine the priority of pressure management, which is convenient for guiding pressure management during the operation and maintenance phase and assisting in identifying leakage areas.

[0088] The network energy surplus ratio E srThe larger the surplus energy of the node, the larger the surplus pressure reduction space. This area is used as the priority area for pressure management and is the basis for judging the priority of pressure management in each partition. The formula is as follows:

[0089]

[0090] Where: E sr E is the network energy surplus ratio, %. E1 is the node surplus energy within each PMA partition, Kw. e E is the effective energy Kw of nodes within each PMA partition. t is the total node energy within each PMA partition, Kw. γ is the density of water, 9800N / m 3 .Q i is the traffic volume of node i within the region, L / s; H min Minimum service head of the i-th node in the pipe network, m. G i is the actual service water head of node i. n is the total number of nodes in each PMA partition.

Claims

1. A design method for optimizing the PMA partition of a water supply network and simultaneously optimizing the DMA partition, characterized in that: The following steps are involved: Step 1: Establish a hydraulic model of the water supply network for simulating the daily operation status of the network and calibrate it according to the monitoring data; Step 2: Generate a topographic map of the water supply network based on the ground elevation data of the network, and then set the maximum allowable height difference Δh for the terrain height difference used for zoning based on the topographic map. max , and the terrain height difference Δh around the pipe network is set at Δh max The pipe network within the range is classified into a zone, thus initially forming a PMA zone; then the average pressure of each PMA zone is calculated. and find the The closest pipe network node is used as the pressure center point of this PMA zone; Step 3: Count the shortest paths between all nodes and the pressure center of each PMA partition, and then calculate the weight according to the pressure and the shortest path. Finally, adjust all nodes that are not divided into the PMA partition where the pressure center with the smallest weight is located to the corresponding PMA partition. Step 4: recalculate the average pressure of the partition obtained in step 3, find the pressure center point of the new partition again, and then return to step 3 and re-execute until the repetition of the nodes contained in the previous and next partitions reaches a preset threshold. When the repetition is greater than the threshold, re-execute the partition before step 3 and record it as an alternative solution. Step 5: Based on the PMA partition obtained in step 4, reduce Δh max value to repeat step 2, so as to form multiple DMA partitions with smaller ranges in the PMA partition, and then calculate the average pressure of each DMA partition again, and find the pressure center point closest to the average pressure of the DMA partition, and perform the same process as steps 3-4 to optimize the DMA partition; Step 6: Determine the flow monitoring equipment, pressure control device and valve location according to the partition: For PMA zones: Calculate the water supply path weight ω from the water source point to the zone pressure center point H1 , and with ω H1 The smallest pipe section serves as the main water supply path; Flow monitoring equipment is set up on the pipe section of the shortest water supply path and pressure control equipment is reserved. If, when calculating the main water supply path, the pressure center points of different PMA partitions share a water supply path, all PMA partitions sharing the water supply path are merged into a large PMA partition, and steps 3-4 are repeated to optimize the PMA partitions to form new PMA partitions; then the energy loss path weight ω of the boundary pipe section from the water source point to the PMA partition is calculated. E1 , in ω E1 Add valves to the pipelines that are small and have the least number of passes from the water source to the boundary section of the PMA zone; For DMA partitioning: Use and calculate ω H1 The same method is used to calculate the water supply path weight ω of the pipe section from the water source to the pressure center point of the DMA partition H2 , and then use and calculate ω E1 The energy loss path weight ω on the boundary pipe segment of the DMA partition structure is calculated in the same way E2 ; Weight of water supply path ω H2 Add flow monitoring equipment to the smallest pipeline, and set the energy loss weight ω E2 Add valves to the least number of pipelines; if the DMA partition boundary coincides with the PMA partition boundary to which it belongs, select ω E1 In small pipelines, valves are installed in the pipelines with the least number of passes from the water source point to the boundary pipe section of the PMA zone; Step 7: Use the hydraulic model to calculate the evaluation indicators of the PMA partition and the DMA partition and their respective alternatives. The evaluation indicators include the pressure balance of the pipe network PEC, the number of nodes that meet the water quality requirements U ma and the cost of the pipe network zoning renovation project C; Step 8: Under the premise of ensuring the most balanced pressure and the largest number of nodes that meet water quality requirements in the zone, select the zone with the lowest zone renovation project cost as the final PMA and DMA zone plan; Step 9: Calculate the network energy surplus ratio E for each PMA partition in the final PMA partition scheme. sr , so according to E sr The size of the pressure is used to determine the priority of stress management. sr Larger PMA partitions.

2. The design method according to claim 1, characterized in that: In step 2, the average pressure is calculated by the following formula: in, is the average pressure of a PMA partition, P i is the pressure of any node i in the pipeline network, and n is the total number of corresponding pipeline network nodes in the PMA partition.

3. The design method according to claim 2, characterized in that: In step 3, the function formula of the weight is: Among them, ω is the weight coefficient, and l is the pipe length from any node to the pressure center.

4. The design method according to claim 2, characterized in that: After the step 3 is completed, the following steps are also included: When all the surrounding nodes of a certain node are in the same PMA partition, but the node is divided into other PMA partitions, the node is re-divided into the same PMA partition as the surrounding nodes.

5. The design method according to claim 2, characterized in that: In step 4, the threshold of repeatability is 95%-100%.

6. The design method according to claim 1, characterized in that: In step 6, Weight of main water supply path ω H1 The smaller it is, the more important the pipe section is in the water supply network. The calculation formula is as follows: Among them, ω H1 is the water supply path weight of pipe segment k; l k is the length of pipe section k; q k is the flow rate of pipe section k; d is the diameter of pipe section k; The energy loss weight ω E1 represents energy consumption, ω E1 The smaller it is, the less important the pipeline is. The calculation formula is as follows: Among them, ω E1 is the energy loss path weight of pipe segment k; γ is the water density; s k is the friction coefficient of pipe section k; m is the flow index.

7. The design method according to claim 3, characterized in that: In step 7, the calculation process of the pipe network pressure equalization PEC includes: The network pressure balance PEC is used to indicate the degree of dispersion of the node pressure of the partition where the partition flow accounts for the weight of the entire water supply network flow and the average pressure of the partition. The smaller the value, the closer the node pressure is to the average pressure, indicating that the partition pressure is more balanced; the calculation formula is: Where M is the number of pipe network partitions, n is the total number of nodes contained in the mth partition; P i is the pressure of the i-th node in the m-th partition; is the average pressure of nodes in the mth partition, Q m is the sum of the water demand of the nodes in the mth partition, W 总 It is the total water consumption of the system.

8. The design method according to claim 3, characterized in that: In step 7, the pipe network zoning reconstruction project cost C is calculated by the following formula: in, Cost of purchasing the nth flow equipment; Installation costs for the nth flow device; The purchase cost of the nth valve; Installation cost for the nth valve; The cost of purchasing the nth pressure control device; Installation cost for the nth pressure control device; K f is the total number of flow devices; K v is the total number of valves; K p is the total number of pressure control devices.

9. The design method according to claim 3, characterized in that: In step 7, the number of nodes that meet the water quality requirements is U mq Calculated by the following formula: U mq =∑[T i ≤T max ] Among them, T i is the water age of the i-th node in the pipe network; T max U is the maximum water age allowed at the node when the free chlorine at the end of the pipe network meets the national water quality standards; j is the upstream node connected to node i; q ki is the pipe flow rate of pipe k connected to node i; T k is the water age of the upstream node connected to node i; t ki is the water flow time of pipe section ki; U mq is the total number of nodes whose water quality meets the water quality requirements. i ≤T max The value is 1, when T i >T max The value is 0.

10. The design method according to claim 3, characterized in that: In step 9, the network energy surplus ratio E sr The calculation process includes: Pipeline network energy surplus ratio E sr Indicates the size of the node's surplus energy. The larger the value, the larger the surplus voltage reduction space. The calculation formula is as follows: Among them, E1 is the surplus energy of nodes within each PMA partition; E e is the effective energy of nodes within each PMA partition; E t is the total node energy within each PMA partition; γ is the water density; Q i is the traffic volume of node i within the region; H min Minimum service head of the i-th node of the pipe network; H i is the actual service water head of node i; n is the total number of nodes in each PMA partition.

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