CN-121981436-A - Combined optimization energy-saving scheduling method and system for raw water and clear water lifting pump station of water plant

CN121981436ACN 121981436 ACN121981436 ACN 121981436ACN-121981436-A

Abstract

Aiming at the problems that the traditional pump station scheduling depends on manual experience, lacks global optimization, has serious energy waste and the like, the invention provides a water plant raw water and clear water lifting pump station combined optimization energy-saving scheduling method and system. The method comprises the steps of establishing a flow-lift and flow-efficiency relation model, deriving a performance formula under any frequency by a variable frequency pump based on a similarity law, carrying out first-stage optimization scheduling, adopting a dynamic programming algorithm to target the minimum total work of the system, determining the optimal flow of a water taking pump station in each period and the optimal water storage level of a clean water tank, meeting the conditions of flow balance, water level constraint and the like, carrying out second-stage optimization scheduling, adopting a genetic algorithm to target the minimum total power of a pump set, optimizing the combination and the operation frequency of the water pump in each period, and introducing a flow and lift deviation punishment item. The invention realizes the whole flow collaborative optimization of water intake, water storage and water supply, has the energy saving rate of more than 10 percent, reduces the operation cost, adapts the dynamic change of the water source tide level and the water demand, and improves the dispatching intelligence level.

Inventors

ZENG WU
LIU HAIHUA
SHI ZHAN
CAI ZHENYIN
WANG XUAN
ZHAO YAN
HE JUNGUO

Assignees

江苏江南水务股份有限公司
广州大学

Dates

Publication Date: 20260505
Application Date: 20251223

Claims (10)

1. The combined optimization energy-saving scheduling method for the raw water and clear water lifting pump station of the water plant is characterized by comprising the following steps of: s1, modeling water pump performance, collecting operation data of each water pump in a water intake pump station and a water supply pump station in a water plant under different working conditions, and establishing a flow-lift relation model and a flow-efficiency relation model of each water pump; s2, first-stage optimized scheduling, namely dividing a preset scheduling period into a plurality of operation periods, and carrying out optimizing calculation according to the minimum total work done by the system in the scheduling period based on the predicted user water demand and the predicted water source liquid level of each period, so as to determine the optimal target water supply flow of the water intake pump station in each period and the optimal target water storage level of the clean water tank in each period; S3, second-stage optimal scheduling, namely determining a specific water pump combination which needs to be started in a water intake pump station and a water supply pump station in a certain period and the optimal operation frequency of starting the water pumps by taking the minimum total power of the pump groups started in the certain period as a target.
2. The method of claim 1, wherein the acquiring the operation data of each water pump in the water intake pump station and the water supply pump station in the water plant under different working conditions comprises: through historical operation data or field test, the water pump is collected at different operation frequencies Lower multiple sets of flow rates Lift of lift And efficiency of Data.
3. The method of claim 2, wherein the building of the flow-head relationship model and the flow-efficiency relationship model for each water pump comprises: the second order polynomial least square method is adopted to respectively establish the flow of the pump under the rated frequency -Head Fitting formula and flow rate Efficiency of Fitting a formula; Flow rate -Head The formula adopts , Wherein , And , The coefficient is calculated by a least square method; for variable frequency pumps, the ratio at any frequency can be deduced from the law of similarity of the pumps The following performance formula.
4. The method of claim 1, wherein the objective function of the first level of optimized schedule is: ; ; = ; Wherein, the The total work of the water taking pump house and the water supply pump house is performed, Is the density of water, g is the gravitational acceleration, In order to get the water pump lift at the t hour of the pump house, For taking the water supply flow of the pump house at the t hour, For supplying water to pump lift for Fang Di t hours, To supply water to the water supply pump Fang Di t hours, Is the pipeline friction of the water taking pump house.
5. The method of claim 4, wherein the constraint on the first level optimized schedule objective function comprises: The daily water supply flow balance constraint, Wherein Taking 0.03 as a self-water consumption coefficient of a water plant; The water supply capacity of the water taking pump house is restricted, , Wherein 、 The lowest water supply flow and the highest water supply flow of the water taking pump house per hour are respectively adopted; clear water tank water level constraint , Wherein 、 The lowest water level and the highest warning water level are safely produced for the clean water tank respectively.
6. The method of claim 5, wherein the first level of optimized scheduling further comprises: Firstly giving an initial water level of the clean water tank at the beginning of a scheduling period, then carrying out distribution optimization of water supply flow of a water taking pump house time by time, and ending the water level of the clean water tank at the end of the scheduling period to be the same as the initial water level; the day is taken as a dispatching cycle, the dispatching cycle is divided into 24 operation time periods, the operation time periods are taken as phase variables, the water level of the clean water tank is discretized, and the highest water level of the clean water tank is obtained And the lowest water level Equally dividing the mixture into n parts; the adjustable liquid level section of the clean water tank of the water plant is 2.4-3.4m, and is equally divided into 10 parts, i=0.1m; the clean water tank water level at the end of each stage is set as a state variable, and the clean water tank water level at the end of any stage can be +( - ) N+1 cases in total; the state transition equation is: ; According to Bottom area of clean water basin And Solving the corresponding water supply flow of the water taking pump house Solving according to a sequential method, wherein a recurrence equation of the dynamic programming model is as follows: ; =0; Wherein, the To be from the initial water level of the clean water tank Clear water pool water level to the end of the t stage Is used to determine the cumulative minimum objective function value of (1), To be from the initial water level of the clean water tank The accumulated minimum objective function value of the clean water tank water level Zt-1 to the end of the t-1 stage, The water level of the clean water tank at the end of the t-1 stage is Zt-1, and the water supply flow of the water taking pump house is Stage objective function values at that time; And the optimal flow distribution scheme of each operation period of the water taking pump house all day and the optimal water level process line of the clean water tank can be obtained through solving.
7. The method of claim 1, wherein the second level of optimized scheduling includes establishing a second scheduling model and solving the second scheduling model, wherein establishing the second scheduling model includes: Solving the pump set collocation problem of the water taking pump house and the water supply pump house by using a genetic algorithm, and taking the total power of the minimum system as a target ; In order to ensure that the scheduling result of the pump house has both energy conservation and hydraulic working condition rationality, a scheduling optimization principle and operation constraint are introduced on the basis of electricity consumption calculation: Minimizing the head deviation, so that the operation head Hi (Q) of each pump is as close to the system head as possible; The running flow of a single pump of the water supply pump room is controlled to be in the range of 40% -130% of the rated flow; Variable frequency pump operating frequency ranges {36,50 Step size of 0.01 ; = { Qtarget±qtarget x 1% }, Is the flow of the ith water pump.
8. The method of claim 7, wherein the second level of optimized scheduling includes building a second scheduling model and solving the second scheduling model, wherein solving the second scheduling model includes: and (3) taking the weighted sum of the total operation energy consumption and the penalty term as a target, and constructing an objective function: ; Wherein, the Is the flow rate of the ith water pump, Is the pump lift, is determined by the combination of pump type and frequency, For the efficiency of the operation of the pump, For the purpose of motor efficiency, =9810N/m 3, gravitational potential energy constant, To penalize the deviation of the total flow from the target water supply flow, Punishment for pump outlet head exceeding the required head portion of the system; the flow deviation penalty term adopts a piecewise function form, is set to be linear in an allowable error range, and is converted into nonlinear weighting after exceeding.
9. The method according to claim 8, wherein the solving the second scheduling model is performed by a genetic algorithm, comprising the steps of: s31, adopting a heuristic and random mixing initialization strategy, wherein the heuristic part estimates reasonable pump combination and frequency based on the target flow; s32, adopting a tournament selection mechanism, randomly selecting two individuals from the population each time, and reserving a better fitness person; s33, performing fixed point crossing on the gene layer, and performing structure-retaining recombination only between the gene pairs; S34, combining two variation mechanisms, namely pump replacement variation, and replacing the number and frequency of a pump at a certain position; Frequency creep variation, wherein the current frequency is disturbed in a frequency list, so that local searching capability is enhanced; If the adaptation degree is not improved for 50 continuous generations, the mutation rate is improved; S35, fixedly reserving the optimal individual with the fitness of 2 before each generation; S36, in order to improve the reliability of the solution, the genetic algorithm is repeatedly operated for preset times in each hour, the optimal solution meeting the deviation requirement is screened, and if no feasible solution exists, the suboptimal solution is selected as a reference, so that the implementation in engineering practice is ensured.
10. A water plant raw water and clean water lift pump station joint optimization energy saving dispatch system for operating the method of any one of claims 1 to 9, comprising: The performance modeling module is used for acquiring operation data of each water pump in a water intake pump station and a water supply pump station in the water plant under different working conditions and establishing a flow-lift relation model and a flow-efficiency relation model of each water pump; The first-stage optimization module divides a preset scheduling period into a plurality of operation periods, performs optimization calculation according to the minimum total work done by the system in the scheduling period based on the predicted user water demand and the predicted water source liquid level of each period, and determines the optimal target water supply flow of the water intake pump station in each period and the optimal target water storage level of the clean water tank in each period; The second-stage optimizing module is used for determining a specific water pump combination which is required to be started in a water taking pump station and a water supply pump station in a certain period and the optimal operation frequency of starting the water pumps by taking the minimum total power of the pump group started in the certain period as a target; And the control module is used for sending a control instruction to the control unit of the pump station according to the water pump combination and the operating frequency output by the second-stage optimization module.

Description

Combined optimization energy-saving scheduling method and system for raw water and clear water lifting pump station of water plant Technical Field The invention belongs to the field of energy-saving control of water supply systems of water plants, and relates to a method and a system for jointly optimizing energy-saving scheduling of raw water and clear water lifting pump stations of a water plant. Background Many water plants, especially along the river and coastal water plants, have water levels of water sources (such as the Yangtze river) which can show periodic and large-amplitude fluctuation due to tide and other factors. The water supply system of such water plants generally includes a water intake pump station (primary pump station) for taking water from a water source, a clean water tank for regulation and a water supply pump station (secondary pump station) for supplying water to a user pipe network. In actual operation, the actual lift of the water intake pump station is directly affected by the change of the water level of the water source, and the load of the water supply pump station is changed depending on the water demand of the user side. At present, the scheduling of such pump stations is mostly dependent on the experience of the operators, and is manually and independently adjusted. For example, the water pump is started and stopped simply according to the water level of the clean water tank, or the frequency of the water supply pump is regulated according to the pipe network pressure. This scheduling approach has significant drawbacks: 1. The lack of global optimization is that the water intake pump station and the water supply pump station are regarded as independent systems, and the water intake pump station and the water supply pump station cannot be considered jointly with the regulation capacity of the clean water tank, so that the system integrally operates in a non-optimal state. 2. The energy waste is serious, namely, the water taking time cannot be planned according to the change rule of the water source liquid level, and the water supply requirements of all time periods cannot be accurately matched, so that the water pump unit often deviates from the high-efficiency working area to operate, and huge electric energy waste is caused. 3. The operation cost is high, the power consumption is one of the most important operation costs of the water plant, and the unreasonable scheduling mode directly leads to the high operation cost. Disclosure of Invention In order to solve the problems in the background technology, the invention provides a method and a system for jointly optimizing energy-saving scheduling of raw water and clear water lifting pump stations of a water plant. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: A water plant raw water and clear water lifting pump station combined optimization energy-saving scheduling method comprises the following steps: s1, modeling water pump performance, collecting operation data of each water pump in a water intake pump station and a water supply pump station in a water plant under different working conditions, and establishing a flow-lift relation model and a flow-efficiency relation model of each water pump; s2, first-stage optimized scheduling, namely dividing a preset scheduling period into a plurality of operation periods, and carrying out optimizing calculation according to the minimum total work done by the system in the scheduling period based on the predicted user water demand and the predicted water source liquid level of each period, so as to determine the optimal target water supply flow of the water intake pump station in each period and the optimal target water storage level of the clean water tank in each period; S3, second-stage optimal scheduling, namely determining a specific water pump combination which needs to be started in a water intake pump station and a water supply pump station in a certain period and the optimal operation frequency of starting the water pumps by taking the minimum total power of the pump groups started in the certain period as a target. Further, the operation data of each water pump in the water intake pump station and the water supply pump station in the water plant under different working conditions comprises: through historical operation data or field test, the water pump is collected at different operation frequencies Lower multiple sets of flow ratesLift of liftAnd efficiency ofData. Further, the establishing a flow-lift relation model and a flow-efficiency relation model of each water pump comprises the following steps: the second order polynomial least square method is adopted to respectively establish the flow of the pump under the rated frequency -HeadFitting formula and flow rateEfficiency ofFitting a formula; Flow rate -HeadThe formula adopts,Wherein,And,The coefficient is calculated by a least square method; for variable frequency