CN1974958A - Intelligent pressure regulating water supply controlling method - Google Patents

Intelligent pressure regulating water supply controlling method Download PDF

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Publication number
CN1974958A
CN1974958A CNA2006101476612A CN200610147661A CN1974958A CN 1974958 A CN1974958 A CN 1974958A CN A2006101476612 A CNA2006101476612 A CN A2006101476612A CN 200610147661 A CN200610147661 A CN 200610147661A CN 1974958 A CN1974958 A CN 1974958A
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China
Prior art keywords
water pump
water
water supply
pressure
controller
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CNA2006101476612A
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CN100511068C (en
Inventor
贾书洪
刘钢
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Shanghai Lianda energy Polytron Technologies Inc
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SHANGHAI LIANDA ENERGY-SAVING SCIENCE TECHNOLOGY Co Ltd
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Priority to CNB2006101476612A priority Critical patent/CN100511068C/en
Publication of CN1974958A publication Critical patent/CN1974958A/en
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    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02ATECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A20/00Water conservation; Efficient water supply; Efficient water use

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Abstract

The present invention belongs to the field of electronic and control technology. In the concrete, it relates to an intelligent pressure-regulated water supply energy-saving control method. Said method includes the following several steps: water pump unit can be used for pumping water and supplying water to user, the pressure gauge positioned in main pipeline can be used for transferring the detected pressure to the controller, and said controller can adopt PID regulation combined fuzzy control method and can utilize control box to control water pump operation and its operation frequency. Said invention also provides the working principle of said water supply control method and its concrete operation steps.

Description

A kind of intelligent pressure regulating water supply controlling method
Technical field
The invention belongs to electronics and control technology field, be specifically related to a kind of intelligent pressure regulating water supply controlling method.
Background technology
It is closely related with people's activity in production of living to supply water, and a large amount of electric energy use aspect water supply.Because all multifactor influences such as designing requirement, variation in plant parameters, demand end demand uncertainty make waste of electric energy serious.Cutting the waste is the active demand of social benefit, economic benefit.
At present, water works water is after treatment generally pumped to it in reservoir by small pump and stores.When the terminal use needs water, start supply-water pump water is transported to each user terminal.Traditional water system is regulated output and adopted two kinds of methods: 1, many parameters, water pump parallel running that model is identical increase or reduce water pump according to demand at any time; 2, adopt the watt level difference, the water pump parallel running that lift is close or identical is driven different water pumps according to different demands, makes pump characteristic and pipe network curve fitting, reaches purpose of energy saving.For guaranteeing pressure balance in the water pipe, adopt pressure in outfall sewer setting pressure table monitoring system.When hypertonia, pass through the aperture of the pressure valve of adjustment bypass valve or end, to guarantee that hydraulic pressure is in certain safe pressure scope in the water pipe.Though such regulative mode has played the effect of keeping security of system pressure in a sense, this is to be prerequisite with the water supply power that increases water pump and waste great lot of water resources.
Generally speaking, every day, there were three peak periods in water supply volume, promptly was morning, noon and night, and the other times water supply volume is not very big.Except that water use peak, the most of the time flow is less during water supply.But water pump design is the maximum load design during by power frequency operation, because load end actual demand pressure is to be in the variation that does not stop, and the feed pump of traditional power frequency operation at a time between the section in power output constant, the phenomenon of pressure of supply water greater than actual demand pressure often appears.When the water low ebb, above phenomenon is particularly evident, has so not only wasted a large amount of electric energy, simultaneously when the water low ebb, because the excessive danger that also causes pipeline breaking easily of pressure.Traditional energy-conservation, safeguard measure are regulated the water supply except increase and decrease supply-water pump quantity, also pass through to change the aperture of valve on the supply channel to regulate flow.Open big valve, flow increases; Close minor valve, flow reduces.Though controlled the supply of flow like this, because control accuracy is lower, lot of energy consumption has directly caused the reduction of water application efficiency in throttling.
Water pump design is the maximum load design during by power frequency operation, in design, all leave the surplus about 20%, in the peak period of water (the maximum load phase of water pump output) so, also can only reach about 80% of its rated power, in water low ebb period, because the load of water pump alleviates, the power of consumption is also corresponding thereupon to be reduced, and can reach original about 70%.
Traditional constant pressure water supply is big more according to the water supply volume of water system, its pressure is more little these characteristics just, by certain technological means, only need pressure with system maintain in the scope of pressure of its required maximum water supply volume, make it keep constant pressure water supply, just can realize the bigger energy saving space.
Above characteristic at water system, constant pressure water supply and energy saving equipment, normally by being installed in the teletransmission pressure meter on the water pump water outlet house steward, the discharge pressure information translation is become the 0-5V voltage signal, through the inner PID computing of intelligent controller, draw the analog quantity that changes with condition of loading constantly and send switch board to, and then the rotating speed of control of pump.With the tap water supply system is example, and when the system water amount was big, the pressure in the pipe network was less, and we increase the rotating speed of water pump, to keep the required minimum pressure of system.When the system water amount hour, the pressure in the pipe network is bigger, we just reduce the rotating speed of water pump, the required flow of minimizing system reaches purpose of energy saving.Whole adjustment process all is to be final purpose with the constant of the pressure of keeping system, but we find in practical application and research, and tap water supply system is not a constant voltage.
At the watering supply characteristic of tap water, the someone has proposed the thought of constant pressure water supply at times.Promptly set the different pressures values at the different periods, make water pump institute consumed power can be with the variation of water supply volume dynamic adjustments.So not only can satisfy the working condition requirement of water system, and can be more effectively, energy-saving excavation space fully, make its energy saving space maximization.For example when the water low ebb we only need to provide the pressure of 0.18MPa just to be enough to satisfy system required, the pressure of 0.2MPa kilogram is provided with the little water supply volume peak at noon in the morning, and we just provide system required maximum pressure the water supply volume maximum time when evening.Just saved a large amount of electric energy again with respect to common constant pressure frequency conversion Energy Saving Control mode like this.Though constant pressure water supply has satisfied certain energy-conservation demand at times, because changes of seasons (as summer and winter) and the variation on date (as working day and day off), the same time water supply volume of every day also can be different.In addition, when water supply volume is big,, will cause user side hydraulic pressure deficiency because the increase of water velocity in the pipeline can add large pipeline hydraulic pressure and fall.So, when water use peak, also need replenish certain water pressure and fall to remedy the hydraulic pressure that on pipeline, produces.
Summary of the invention
The object of the present invention is to provide a kind of intelligent pressure regulating water supply and energy saving control method.
The intelligent pressure regulating water supply and energy saving control method that the present invention proposes, adopt intelligent pressure regulating water supply and energy saving control device intelligent pressure regulating to supply water, intelligent pressure regulating water supply and energy saving control device is made up of water pump group 1, pressure meter 3, controller 6, switch board 7, and its structure as shown in Figure 1.Wherein, one end of water pump group 1 connects pond 5 by pipeline, the other end connects user side by main water supply pipe 4, main water supply pipe 4 between water pump group 1 and the user side is provided with pressure meter 3, pressure meter 3 connects controller 6, the other end of controller 6 connects switch board 7, and switch board 7 connects water pump group 1.Water pump group 1 is formed in parallel by N water pump, and wherein, N is the 1-6 group; Its concrete steps are as follows: water pump group 1 is extracted the water in the pond 5 out and is sent to the user by main water supply pipe, the pressure meter 3 that is arranged in trunk line is delivered to controller 6 to detected pressure, controller 6 adopts PID to regulate in conjunction with fuzzy (Fuzzy) control method, adopt water pump output sum frequency to come estimated flow percentage, promptly control by the start and stop and the operating frequency of water pump in 7 pairs of water pump groups 1 of switch board, when the main water supply pipe total flow is 60% when following, can adopt the traditional PID adjustment constant pressure water supply, when output surpasses 60% of total flow, to add up to the individual water pump of N (N 〉=2) is example, by first water pump of frequency conversion soft start M1, when first water pump M1 running at full capacity is still under-voltage, second water pump M2 of frequency conversion soft start, with first water pump M1 switch to power frequency or with second water pump M2 with operation frequently, and the like, when need use the 3rd water pump M3, the switching of the 3rd water pump M3 is second water pump M2 together, and the like, until last water pump.
The present invention judges when what of hourly water consumption, to increase or to reduce the pressure target value of this period by the method for pump motor output sum frequency estimated flow.Main purpose has two, and the one, according to the power output of the big I real-time monitoring of water supply volume motor, promptly adjust the frequency converter output frequency, to satisfy the urban water demand of different periods; The 2nd, the pipeline hydraulic pressure that produces on pipeline when replenishing water use peak falls.Compare with constant voltage control at times, this method real-time is better, and the energy saving space is bigger.
The present invention adopts the method for judging flow by the total operating frequency of pump motor indirectly, because the size of water supply flow and motor speed and frequency of supply are approximated to linear relationship.So, the size that can come the approximate estimation flow by the sum frequency value of motor operation.
What the inventive method adopted is that traditional PID adjustment is in conjunction with fuzzy (Fuzzy) control algolithm.Conventional PID controllers is simple in structure, has certain robustness, realizes that easily steady-state error is little, and the control accuracy height can satisfy the requirement of most of Industry Control.But, in a lot of Industry Control in various degree have non-linear, large time delay, parameter time varying and a model uncertainty, thereby common PID controller is difficult to obtain satisfied control effect.The advantage of fuzzy control is to access the better dynamic response characteristic, and need not to know the Mathematical Modeling of controlled device, and compliance is strong, and the rise time is fast, and robustness is good.But also there is intrinsic shortcoming in fuzzy control, is subjected to the restriction of the limited grade of fuzzy rule easily and causes error.This method has adopted the compound control of Fuzzy-PID.Remedied the deficiency of simple employing pid algorithm.
The method that the present invention adopts water pump output sum frequency to come estimated flow is to replace the use of flow meter.
In the water system of the present invention, quasi real time regulate and control to upgrade to the intelligent pressure regulating real-time monitoring at times, control to adjust the supply-water pump power output in real time according to traffic demand by original constant voltage.
Beneficial effect of the present invention:
1. compare with constant voltage control at times, this method is not limited by the period, but goes the goal of regulation and control force value according to the actual used water amount, so real-time is better, the energy saving space is bigger.
2. adopted the method that PID controls and fuzzy control combines, remedied the deficiency of simple employing PID control method, the control effect more fast, steadily.
3. the method that adopts water pump output sum frequency to come estimated flow has avoided installing at trunk line the inconvenience of flow meter, simultaneously, has also saved fund.
Description of drawings
Fig. 1 is a structural diagrams of the present invention.
Fig. 2 is the pressure regulation curve of embodiment 1.
Fig. 3 is embodiment 1 a compensatory pressure fuzzy control curve.
Number in the figure: 1 is the water pump group, and 2 is water pump controllable electric power line, and 3 is pressure meter, and 4 is main water supply pipe, and 5 is the pond, and 6 is controller, and 7 is switch board, and 8 is the pressure detecting signal line.
The specific embodiment
Further specify the present invention below by embodiment.
Embodiment 1: be made up of 75KW water pump group, 1MPa pressure meter, LDJ-3000 controller, LDJ-2900 switch board, its structure as shown in Figure 1.Wherein, an end of water pump group connects the pond by pipeline, and the other end connects user side by main water supply pipe, main-supply between water pump group and the user side is provided with pressure meter, pressure meter connects controller, and the other end of controller connects switch board, and switch board connects the water pump group.
As shown in Figure 2, less in water supply volume, when water supply flow is low, promptly, can adopt PID adjusting constant pressure water supply at 60% when following of total flow.When reaching water use peak, output will be above 60% of total flow, establishes that the water pump number is N in the water pump group, and each water pump highest frequency is that 50Hz calculates 3 the highest output of water pump 150Hz.In addition, the switching mode of each water pump adopts soft the opening of circulation, promptly when the highest frequency that reaches of first water pump, this water pump is switched to power frequency, and next water pump from the 0Hz frequency conversion soft start, is increased the 3rd pump if desired, and order is the same.When needs subtract pump, subtract pump according to the principle of at first stopping earlier.Before back increase pump did not reach 30Hz, because the counter-pressure that main frequency water pump produces its, its role was very little, so in this scope, the compensatory pressure amplitude is little.In view of the above, it is as shown in table 1 to draw fuzzy control table.
Table 1 compensatory pressure percentage fuzzy control table
3 water pump sum frequencys (Hz) <80 80-85 85-90 90-95 95-100 100-120
Compensatory pressure percentage (%) 0 10 20 30 40 45
3 water pump sum frequencys (Hz) 120-125 125-130 130-135 135-140 140-145 145-150
Compensatory pressure percentage (%) 50 55 60 75 90 100

Claims (1)

1, a kind of intelligent pressure regulating water supply and energy saving control method, it is characterized in that adopting intelligent pressure regulating water supply and energy saving control device intelligent pressure regulating to supply water, intelligent pressure regulating water supply and energy saving control device is by water pump group (1), pressure meter (3), controller (6), switch board (7) is formed, wherein, one end of water pump group (1) connects pond (5) by pipeline, the other end connects user side by main water supply pipe (4), main water supply pipe (4) between water pump group (1) and the user side is provided with pressure meter (3), pressure meter (3) connects controller (6), the other end of controller (6) connects switch board (7), and switch board (7) connects water pump group (1); Water pump group (1) is formed in parallel by N water pump, and wherein, N is the 1-6 group; Its concrete steps are as follows: water pump group (1) is extracted the water in pond (5) out and is sent to the user by main water supply pipe, the pressure meter (3) that is arranged in trunk line is delivered to controller (6) to detected pressure, controller (6) adopts PID to regulate in conjunction with fuzzy Fuzzy control method, adopt water pump output sum frequency to come estimated flow percentage, promptly the start and stop and the operating frequency of water pump in the water pump group (1) are controlled by switch board (7), when the main water supply pipe total flow is 60% when following, can adopt the traditional PID adjustment constant pressure water supply, when output surpasses 60% of total flow, at first by first water pump of frequency conversion soft start M1, when first water pump M1 running at full capacity is still under-voltage, second water pump M2 of frequency conversion soft start then, with first water pump M1 switch to power frequency or with second water pump M2 with operation frequently, and the like, when need used the 3rd water pump M3, the switching of the 3rd water pump M3 was with second water pump M2, and the like, until last water pump.
CNB2006101476612A 2006-12-21 2006-12-21 Intelligent pressure regulating water supply controlling method Expired - Fee Related CN100511068C (en)

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Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102080643A (en) * 2009-11-27 2011-06-01 株式会社日立产机系统 Water supply device and water level controlling means
CN102269978A (en) * 2010-06-07 2011-12-07 上海熊猫机械(集团)有限公司 Time interval optimizing water supply controller
CN103981923A (en) * 2014-05-30 2014-08-13 李英杰 Compensation energy-saving water supply system
CN104563212A (en) * 2014-07-22 2015-04-29 上海大众祥源动力供应有限公司 Variable-frequency constant-pressure make-up water control system on basis of PI (Proportional-Integral) regulation
EP2890002A3 (en) * 2013-12-31 2015-10-14 LSIS Co., Ltd. Method for controlling inverter
CN105492772A (en) * 2013-04-12 2016-04-13 滨特尔泵集团公司 Water booster control system and method
CN106523339A (en) * 2016-12-22 2017-03-22 杭州杭开新能源科技股份有限公司 Direct-connection pressurizing water supply unit and pump-adding same-frequency operation control method
CN107893751A (en) * 2017-11-25 2018-04-10 蚌埠市鑫源机电设备有限公司 A kind of pump operation based on the linkage of more pumps regulates and controls method
CN107989781A (en) * 2017-11-25 2018-05-04 蚌埠市鑫源机电设备有限公司 A kind of pump operation regulator control system of multistage linking
CN109307316A (en) * 2018-09-21 2019-02-05 中冶东方工程技术有限公司 Energy-saving control method and heat exchange station for frequency conversion pump group
CN111322231A (en) * 2020-03-06 2020-06-23 上海英威腾工业技术有限公司 Multi-pump linkage control method and system
CN111764469A (en) * 2020-09-03 2020-10-13 成都同飞科技有限责任公司 Remote intelligent constant-pressure water supply system
CN114413360A (en) * 2021-12-31 2022-04-29 威乐(中国)水泵系统有限公司 Hydraulic module
CN118273933A (en) * 2024-05-08 2024-07-02 江苏派力克流体科技有限公司 Intelligent pressure compensation control system and method for pump body

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101982620A (en) * 2010-10-21 2011-03-02 中国市政工程东北设计研究总院 Energy-saving control method for water supply project
CN104532906A (en) * 2014-12-02 2015-04-22 长沙新顺昌水净化设备有限公司 Automatic water supply device and method

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102080643A (en) * 2009-11-27 2011-06-01 株式会社日立产机系统 Water supply device and water level controlling means
CN102269978A (en) * 2010-06-07 2011-12-07 上海熊猫机械(集团)有限公司 Time interval optimizing water supply controller
CN105492772A (en) * 2013-04-12 2016-04-13 滨特尔泵集团公司 Water booster control system and method
EP2890002A3 (en) * 2013-12-31 2015-10-14 LSIS Co., Ltd. Method for controlling inverter
US9798296B2 (en) 2013-12-31 2017-10-24 Lsis Co., Ltd. Method for controlling inverter
CN103981923B (en) * 2014-05-30 2015-05-13 李英杰 Compensation energy-saving water supply system
CN103981923A (en) * 2014-05-30 2014-08-13 李英杰 Compensation energy-saving water supply system
CN104563212A (en) * 2014-07-22 2015-04-29 上海大众祥源动力供应有限公司 Variable-frequency constant-pressure make-up water control system on basis of PI (Proportional-Integral) regulation
CN106523339A (en) * 2016-12-22 2017-03-22 杭州杭开新能源科技股份有限公司 Direct-connection pressurizing water supply unit and pump-adding same-frequency operation control method
CN107893751A (en) * 2017-11-25 2018-04-10 蚌埠市鑫源机电设备有限公司 A kind of pump operation based on the linkage of more pumps regulates and controls method
CN107989781A (en) * 2017-11-25 2018-05-04 蚌埠市鑫源机电设备有限公司 A kind of pump operation regulator control system of multistage linking
CN107893751B (en) * 2017-11-25 2019-06-04 蚌埠市鑫源机电设备有限公司 A kind of pump operation regulation method based on more pump linkages
CN109307316A (en) * 2018-09-21 2019-02-05 中冶东方工程技术有限公司 Energy-saving control method and heat exchange station for frequency conversion pump group
CN109307316B (en) * 2018-09-21 2020-07-17 中冶东方工程技术有限公司 Energy-saving control method for variable-frequency pump set and heat exchange station
CN111322231A (en) * 2020-03-06 2020-06-23 上海英威腾工业技术有限公司 Multi-pump linkage control method and system
CN111764469A (en) * 2020-09-03 2020-10-13 成都同飞科技有限责任公司 Remote intelligent constant-pressure water supply system
CN114413360A (en) * 2021-12-31 2022-04-29 威乐(中国)水泵系统有限公司 Hydraulic module
CN118273933A (en) * 2024-05-08 2024-07-02 江苏派力克流体科技有限公司 Intelligent pressure compensation control system and method for pump body

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Address after: 200433 No. 11, Lane 100, Yangpu District, Shanghai (Centralized Registration Place)

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