CN114912291A

CN114912291A - Newly-added monitoring point arrangement method and device serving water supply network hydraulic model checking

Info

Publication number: CN114912291A
Application number: CN202210622119.7A
Authority: CN
Inventors: 周华; 俞亭超; 韩万玉; 林犇; 王蕾; 邵煜; 翁晓丹
Original assignee: Zhejiang University ZJU; PowerChina Huadong Engineering Corp Ltd
Current assignee: Zhejiang University ZJU; PowerChina Huadong Engineering Corp Ltd
Priority date: 2022-06-01
Filing date: 2022-06-01
Publication date: 2022-08-16

Abstract

The invention discloses a method for arranging newly added monitoring points serving for water supply pipe network hydraulic model checking, which comprises the following steps: step 1, calculating and obtaining a pressure sensitivity matrix and a measurement node set of each node of the water supply network under a standard working condition of the water supply network hydraulic model; step 2, constructing a target function for calculating the monitoring effect distance between the node to be arranged and the existing monitoring point, and taking the node corresponding to the minimum solution of the target function as a newly added monitoring point; and 3, after adding the newly added monitoring points into the existing monitoring points, repeating the process in the step 2 until the arrangement state of the newly added monitoring points meets the termination condition. The invention also provides a newly added monitoring point arrangement device based on the method. According to the method provided by the invention, the measurement node set is introduced, so that the monitoring points of the scheme are finally arranged, the monitoring capability of the original monitoring points is considered, the defects of the original monitoring points are overcome, and the checking precision of the whole water supply network is improved.

Description

Newly-added monitoring point arrangement method and device serving water supply network hydraulic model checking

Technical Field

The invention belongs to the technical field of urban water supply pipe network arrangement, and particularly relates to a method and a device for arranging newly added monitoring points serving for water supply pipe network hydraulic model checking.

Background

In recent years, intelligent management of urban water supply networks has become a major trend. In order to better understand the current operating conditions of a pipe network, water supply network real-time hydraulic models are increasingly widely used in practice. The high-precision and high-efficiency real-time hydraulic model of the pipe network is established and effectively utilized, so that the safety of urban water supply can be effectively guaranteed. In order to improve the accuracy of the water supply network hydraulic model, data such as node water demand and the like in the model need to be checked at a certain frequency by relying on monitoring data of monitoring points arranged in a pipe network. Therefore, the accuracy of the final hydraulic model is greatly related to the quality of the arrangement scheme of the monitoring points.

In the actual operation of a water supply network, the existing sensors are generally not completely removed or replaced by laying new sensors. Therefore, how to arrange a new monitoring point and consider the original monitoring point at the same time, so that the newly arranged monitoring point can be complementary with the monitoring data of the old monitoring point, and the method is a problem worthy of research. In view of the above, the invention provides a method for arranging the newly added monitoring points serving for the water supply network hydraulic model checking, which can effectively arrange the new monitoring points in the monitoring blind areas of the original monitoring points and improve the hydraulic model checking precision.

Patent document CN106870955B discloses a monitoring point optimal arrangement method for water demand inversion of water supply network nodes, which includes: 1. selecting a reference working condition to carry out pipe network adjustment to obtain node pressure and pipeline flow, obtaining a pressure sensitivity matrix and establishing a pressure influence coefficient matrix; 2. inverting the node water demand by using the monitoring values of the existing monitoring points, adjusting to obtain the node pressure and the pipeline flow, and establishing an error matrix; 3. multiplying the pressure influence coefficient matrix by a pressure error matrix, setting a node corresponding to the maximum element of the product as a new pressure monitoring point, and setting a pipeline corresponding to the maximum element of the flow error matrix as a new flow monitoring point; 4. and terminating iteration when the number of the monitoring points reaches the upper limit, otherwise, continuing to calculate, and increasing the monitoring points. The method reduces the error of the inversion algorithm by improving the traditional pressure sensitivity matrix. However, in the method, iterative calculation is still required in the monitoring point arrangement process, and the generation efficiency of the arrangement scheme is not changed.

Patent document CN114429034A discloses a pressure monitoring point moving arrangement method for water quantity checking of a water supply network hydraulic model, which includes: dividing a checking period according to the total number of the nodes of the pipe network and the number of the pressure monitoring sensors; obtaining a Jacobian matrix of the node pressure relative to the node water quantity based on the initialized pipe network hydraulic model; solving a monitoring point moving arrangement scheme according to a Jacobian matrix and an improved implicit enumeration optimization method; according to the monitoring data obtained by the monitoring point position deployment scheme in each checking period, the node water quantity parameters of the water supply network hydraulic model are checked and calculated, and the calculation accuracy is improved. This method introduces perturbation parameters into the pressure sensitivity matrix to simplify the calculation process, but reduces the accuracy of the final result.

Disclosure of Invention

In order to solve the problems, the invention provides a newly added monitoring point arrangement method serving for water supply pipe network hydraulic model checking, which introduces a concept of measuring a node set on the basis of a traditional pressure sensitivity matrix, constructs a target function for calculating the monitoring effect distance between a node to be arranged and the existing monitoring point by combining the node set and the existing monitoring point set, and takes the minimum solution of each time of the target function as the newly added monitoring point, so that the monitoring points of a final arrangement scheme not only consider the monitoring capability of the original monitoring point, but also enable the newly added monitoring point to be in synergistic action with the original monitoring point, simultaneously make up the defects of the original monitoring point, and improve the checking precision of the whole water supply pipe network and a specific area.

A newly-added monitoring point arrangement method for service water supply network hydraulic model checking is provided, the water supply network hydraulic model comprises a topological relation of a water supply network, pipeline information of each pipeline and water demand of each node, and the newly-added monitoring point arrangement method comprises the following steps:

step 1, calculating and obtaining a pressure sensitivity matrix and a measurement node set of each node of the water supply network under a standard working condition of the water supply network hydraulic model, wherein the measurement node set comprises K adjacent node sets nearest to the node, and the K value is set manually;

step 2, according to the pressure sensitivity matrix and the measurement node set obtained in the step 1, constructing a target function for calculating the monitoring effect distance between the node to be arranged and the existing monitoring point, and taking the node corresponding to the minimum solution of the target function as a newly added monitoring point;

and 3, after adding the newly added monitoring points into the existing monitoring points, repeating the process in the step 2 until the arrangement state of the newly added monitoring points meets the termination condition.

Because the transformation of the traditional water supply network is completed by replacing or adding a new sensor, the original monitoring range can be changed by simple removal or replacement, and the problems of overlapping monitoring ranges or blind monitoring points can be caused. On the basis of the traditional pressure sensitivity matrix, the concept of measuring the node set is introduced, the target function of the monitoring effect distance between the node to be arranged and the existing monitoring points is constructed, and the newly added monitoring points are obtained by solving the minimum solution of the target function, so that the monitoring range blind area between each newly added monitoring point and the original monitoring point is minimum.

Specifically, the pipeline information of each pipeline includes the pipeline length, the pipeline diameter and the friction coefficient of each pipeline.

Preferably, the pressure sensitivity matrix in the step 1 is calculated and obtained by an analytical method based on the topological relation of the water supply network hydraulic model and the water demand of each node, and the matrix data obtained by the method is high in accuracy, so that the checking accuracy of the new and old monitoring points in the final arrangement area is improved.

Specifically, the pressure sensitivity matrix is constructed by the following steps:

according to the condition that any node in the water supply network meets the condition that the inflow water quantity is equal to the outflow water quantity, a continuity equation of the node is constructed:

q _i +∑Q _i,j ＝0(i,j∈N)

in the formula, q _i Node Water demand, Q, for node i _i,j The flow of the pipeline with the node i as a starting node and the node j as a tail end node is shown, namely the flow of the pipeline is a negative value when flowing out, and the flow of the pipeline is a positive value when flowing in; n is a node set in the water supply network model;

merging continuity equations corresponding to all nodes, and outputting in a node matrix form:

AQ-q＝0

in the formula (I), the compound is shown in the specification,

an incidence matrix representing the topological relation of the pipe network, n represents the number of nodes in the hydraulic model, p represents the number of pipelines in the hydraulic model,

is the flow vector of the pipeline and is,

is the water demand vector of the node;

meanwhile, the water head difference of nodes at two ends of any pipeline in the water supply network is equal to the water head loss of the pipeline, so that an energy equation of the pipeline is constructed:

H _i,j ＝h _i -h _j

in the formula, H _i,j Head loss, h, for a pipeline having node i as the starting node and node j as the end node _i And h _j Node water heads of a node i and a node j respectively;

and merging energy equations of all pipelines and outputting in a pipeline matrix form:

A ^T h+H＝0

in the formula, A ^T Is a transpose of the correlation matrix and,

is a head vector of the node point and is,

is the head loss vector of the pipeline;

modifying the node matrix and the pipeline matrix according to the change rule of the water demand of the nodes in the water supply network:

a node change matrix: a (Q + Δ Q) - (Q + Δ Q) ═ 0

A pipeline change matrix: a. the ^T (h+Δh)+(H+ΔH)＝0

In the formula (I), the compound is shown in the specification,

is a vector of the change of the flow of the pipeline,

is a change vector of the water demand of the node,

is a vector of the variation of the node water head,

the variation vector of the pipeline head loss is obtained;

according to the obtained matrix and the change matrix, calculating the head loss of the pipeline in the pipe network through the Haiziki formula, and calculating the head loss H of the single pipeline _f Flow Q of pipeline _s Differentiation of (d):

in the formula, H _f Head loss for a certain pipe, Q _s The flow rate of the pipeline, L the length of the pipeline, C the friction coefficient of the pipeline and D the pipe diameter of the pipeline;

the equation containing all the pipeline head losses is as follows:

ΔH＝B ^-1 ΔQ

in the formula, Q _d Conduit flow rate for conduit d, H _d The head loss of the pipeline d is shown, and p is the total number of the pipelines in the hydraulic model;

and (3) carrying out simultaneous and integrated on the formulas to obtain a pressure sensitivity matrix:

specifically, the measurement node set in step 2 is specifically represented by the following formula:

in the formula, J _i Is a set of measurement nodes of the node i, N is a set of all nodes of the water supply network, Dist _i,a And Dist _i,b Respectively representing the hydraulic distances from node i to nodes a and b, Junc _j Representing nodes j in a water supply networkI.e. satisfy Junc ₁ ，Junc ₂ …Junc _K Is the K nodes closest to node i, i and j representing the node numbers.

Specifically, the specific construction process of the measurement node set is as follows:

the distance matrix dist of the initialization node is as follows:

traversing all the relay nodes to update the shortest distance between all the nodes, namely if the relay nodes can reduce the distance between two nodes by going through, updating the distance between two nodes to a new value, and when the traversed node is k, the expression can be rewritten as:

dist _i,j ＝min(dist _i,j ,dist _i,k +dist _k,j )

and finally, searching K nodes with the nearest distance of each node, wherein the nodes form a measurement node set of the node.

Specifically, the hydraulic distance is the shortest distance between two nodes along the pipe section, and is calculated and obtained through a Floyd algorithm based on the topological relation of the water supply network and the pipe section data.

Specifically, the objective function in step 2 has the following specific expression:

wherein G denotes a node at which a monitoring point is to be arranged, G _i Indicating a set of existing watch points, MED _g,i The monitoring effect distance of the monitoring point i relative to the node g is obtained.

Specifically, the expression of the monitoring effect distance is as follows:

in the formula, J _i ∪J _j Measuring the union of node sets for node i and node j, S _i,Junc And representing the sensitivity of the node i node to the target node Junc. S. the _j,Junc Representing the sensitivity of node j to the target node Junc.

Preferably, the termination condition includes:

1. when the number of the arranged monitoring points reaches a preset value;

2. when the monitoring effect distance of the monitoring points to be arranged reaches a threshold value;

any of the above conditions is satisfied, i.e., the operation is terminated.

The invention also provides a newly-added monitoring point arrangement device which comprises a computer memory, a computer processor and a computer program which is stored in the computer memory and can be executed on the computer processor, wherein the computer memory adopts the newly-added monitoring point arrangement method serving for water supply network hydraulic model checking; the computer program when executed by the computer processor implements the steps of: and selecting a standard working condition of the water supply network hydraulic model, inputting the total number of the newly added monitoring points, and outputting an arrangement scheme of the newly added monitoring points through analysis and calculation.

Compared with the prior art, the invention has the beneficial effects that:

the sensitivity vectors are reduced in dimension when the node monitoring capacity is compared, the nodes which can reflect the monitoring effect most are focused, the interference of a large number of nodes with long distance and low sensitivity is eliminated, different monitoring effects and ranges among the nodes can be accurately reflected, the monitoring capacity of original monitoring points can be considered by finally arranged monitoring points, the newly arranged monitoring points and an original sensor system are enabled to act in a synergistic mode, the defects of the original system are overcome, and the checking precision of the whole pipe network and a specific area is improved.

Drawings

FIG. 1 is a schematic flow chart of a method for arranging newly added monitoring points serving for water supply network hydraulic model checking according to the present invention;

fig. 2 is a schematic diagram of the topological relation of the water supply pipe network and the positions of the pressure monitoring points according to the embodiment;

fig. 3 is a diagram of an arrangement scheme output by the newly added monitoring point arrangement device provided in this embodiment;

FIG. 4 is a graph of mean absolute error of nodal pressure versus absolute error provided by the present embodiment;

fig. 5 is a pressure absolute error cumulative probability density distribution diagram provided in this embodiment.

Detailed Description

As shown in fig. 1, a method for arranging newly added monitoring points serving for water supply network hydraulic model verification includes:

step 1, calculating and obtaining a pressure sensitivity matrix and a measurement node set of each node of a water supply network under a standard working condition of a water supply network hydraulic model;

as shown in fig. 2, a pressure sensitivity matrix is constructed according to the topological relation of the water supply pipe network and the position of the pressure monitoring point:

in the water supply network model, there are 3 water plants in total, 4242 nodes (i.e. n is 4242), 4841 pipes (i.e. p is 4841), the total length of the pipe sections is 1576.98 km, there are 48 pressure monitoring points, wherein, the incidence matrix B of the topological relation of the pipe network is as follows:

solving the incidence matrix B by a matrix inversion algorithm to obtain a pressure sensitivity matrix S of the node:

calculating the hydraulic distance between every two nodes in the pipe network by using a Floyd algorithm, and constructing a measurement node set:

initializing the dist matrix according to the starting node, the tail end node and the length data of the pipeline in the model, and then beginning to enumerate the relay nodes to continuously update the dist matrix. An example of the partial values of the hydraulic distance dist matrix calculated using the Floyd algorithm is as follows:

because the index sequence numbers of the nodes in the water supply network model are not greatly related to the positions of the nodes, even the nodes with similar index sequence numbers have large hydraulic distances. Sorting each column of the hydraulic distance matrix dist from small to large, and then intercepting the first K rows (K is 20 in this embodiment), a weighted node set of each node can be obtained, where a weighted node set of a part of nodes is given:

each column in the table is a set of measured nodes of each node, and since the hydraulic distance of a node to itself is the minimum value of 0, the node itself is always included in the set of measured nodes of a node.

Step 2, according to the pressure sensitivity matrix and the measurement node set obtained in the step 1, constructing a target function for calculating the monitoring effect distance between the node to be arranged and the existing monitoring point, and taking the node corresponding to the minimum solution of the target function as a newly added monitoring point:

calculating a monitoring capacity difference value MED between every two nodes in the pipe network according to the sensitivity matrix S and the calculated measurement node set of the nodes, wherein the examples of partial values are as follows:

and 3, after adding the newly added monitoring points into the existing monitoring points, repeating the process in the step 2 until the arrangement state of the newly added monitoring points meets a termination condition, wherein the termination condition comprises the following steps:

1. when the number of the arranged monitoring points reaches a preset value;

any one of the above conditions is satisfied, i.e., the operation is terminated.

The embodiment also provides a newly-added monitoring point arrangement device which comprises a computer memory, a computer processor and a computer program which is stored in the computer memory and can be executed on the computer processor, wherein the computer memory adopts the newly-added monitoring point arrangement method serving for water supply network hydraulic model checking;

the computer program when executed by a computer processor implements the steps of: selecting a standard working condition of the water supply network hydraulic model, inputting the total number of the newly added monitoring points, and outputting the arrangement scheme of the newly added monitoring points through analysis and calculation.

As shown in fig. 3, as a final arrangement scheme, the termination condition at this time is that the number of the newly added monitoring points is 10.

And the water demand of the simulation node at a certain moment is generated by reasonably distributing the total water consumption of the pipe network. And (3) obtaining the pressure value of the node where the sensor is located in the pipe network through adjustment calculation, and adding a noise subject to the conditions that the mean value is 0 and the standard deviation is 1m as a monitoring error to generate the simulation monitoring values of all the monitoring points. The hydraulic model is then checked using the simulated monitoring values. And after the hydraulic model is checked, obtaining a check pressure value of each node in the pipe network, comparing the check pressure value with the real pressure value of the simulation data to obtain an absolute error of the checked pressure, and counting to measure the improvement degree of the checking precision of the new arrangement scheme.

As shown in fig. 4, the node pressure mean absolute error comparison graph includes the original monitoring points, the system random arrangement scheme and the arrangement scheme generated by the method:

according to the arrangement method of the newly added monitoring points, the improvement on the checking precision of the original model is obvious, so that the average absolute error of the nodes is reduced from 1.09m to 0.91 m; if new monitoring points are randomly arranged, even if 10 monitoring points are added under the condition that more monitoring points exist in the pipe network, the improvement of the checking precision is limited.

As shown in fig. 5, in order to draw the pressure absolute error cumulative probability density distribution diagram, the distribution of the node pressure absolute errors can be better observed:

according to the arrangement method of the newly added monitoring points, the improvement on the checking precision of the hydraulic model of the pipe network is very obvious, the pressure absolute error of 80% of the nodes is less than 1.50m, the pressure absolute error of 90% of the nodes is less than 1.83m, and the pressure absolute error of 95% of the nodes is less than 2.00 m. The optimized arrangement scheme also has better performance than the random arrangement scheme, the maximum value of the pressure absolute error is reduced from 2.68m to 2.43m, and the pressure absolute error of each branch point is reduced to a certain degree.

The method provided by the invention can measure the monitoring capability of the existing monitoring points, and arranges the new sensor in the area which is not concerned by the previous monitoring points, thereby having obvious optimization effect on the original nodes with large checking error.

In conclusion, the arrangement method of the newly added monitoring points provided by the invention can consider the monitoring capability of the existing sensor, reduce the blind area of monitoring, improve the checking precision and have practical value.

Claims

1. A newly-added monitoring point arrangement method for service check of a water supply network hydraulic model, wherein the water supply network hydraulic model comprises a topological relation of a water supply network, pipeline information of each pipeline and water demand of each node, and the newly-added monitoring point arrangement method is characterized by comprising the following steps of:

2. The method as claimed in claim 1, wherein the pipeline information of each pipeline includes the length of each pipeline, the diameter of each pipeline, and the friction coefficient.

3. The method as claimed in claim 1, wherein the pressure sensitivity matrix in step 1 is calculated by an analytical method based on the topological relation of the water supply network hydraulic model and the water demand of each node.

4. The method as claimed in claim 1, wherein the set of measurement nodes in step 2 is represented by the following formula:

in the formula, J _i Is a set of measurement nodes of the node i, N is a set of all nodes of the water supply network, Dist _i,a And Dist _i,b Respectively representing the hydraulic distances from node i to nodes a and b, Junc _j Indicating a node j in the water supply network, i.e. meeting Junc ₁ ，Junc ₂ …Junc _K Is the K nodes closest to node i, i and j representing the node numbers.

5. The method as claimed in claim 4, wherein the hydraulic distance is the shortest distance between two nodes along the pipeline, and is calculated by Floyd algorithm based on the topological relation of the hydraulic model of the water supply network and the pipeline data of each pipeline.

6. The method as claimed in claim 1, wherein the objective function in step 2 is expressed as follows:

7. The method as claimed in claim 6, wherein the distance between monitoring effects is expressed as follows:

in the formula, J _i ∪J _j Measuring the union of node sets for node i and node j, S _i,Junc And representing the sensitivity of the node i node to the target node Junc. S _j,Junc Representing the sensitivity of node j to the target node Junc.

8. The method of claim 1, wherein the termination condition comprises:

1. when the number of the arranged monitoring points reaches a preset value;

9. A new monitoring point placement device comprising a computer memory, a computer processor and a computer program stored in said computer memory and executable on said computer processor, wherein said computer memory is adapted to perform the new monitoring point placement method of any of claims 1-8 for use in water supply network hydraulic model verification; the computer program when executed by the computer processor implements the steps of: and selecting a standard working condition of a water supply network hydraulic model, inputting the total number of the newly added monitoring points, and outputting an arrangement scheme of the newly added monitoring points through analysis and calculation.