CN106499009A - A kind of intelligent water supply device and method - Google Patents
A kind of intelligent water supply device and method Download PDFInfo
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- CN106499009A CN106499009A CN201611073119.7A CN201611073119A CN106499009A CN 106499009 A CN106499009 A CN 106499009A CN 201611073119 A CN201611073119 A CN 201611073119A CN 106499009 A CN106499009 A CN 106499009A
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- hydraulic pressure
- converter
- threshold value
- pressure threshold
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- E—FIXED CONSTRUCTIONS
- E03—WATER SUPPLY; SEWERAGE
- E03B—INSTALLATIONS OR METHODS FOR OBTAINING, COLLECTING, OR DISTRIBUTING WATER
- E03B7/00—Water main or service pipe systems
- E03B7/07—Arrangement of devices, e.g. filters, flow controls, measuring devices, siphons or valves, in the pipe systems
- E03B7/075—Arrangement of devices for control of pressure or flow rate
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- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Hydrology & Water Resources (AREA)
- Public Health (AREA)
- Water Supply & Treatment (AREA)
- Control Of Positive-Displacement Pumps (AREA)
Abstract
The invention discloses a kind of intelligent water supply device.Intelligent water supply device of the present invention is specific as follows to the startup of converter, the control method for stopping：Start hydraulic pressure threshold value less than default first and maintain a period of time T when side hydraulic pressure sampled value is discharged1, and a period of time T thereafter2Interior, the maximum for discharging side hydraulic pressure sampled value starts hydraulic pressure threshold value not less than default second, then control converter starts, and otherwise, converter does not start；In converter running, such as there is discharge side hydraulic pressure sampled value and close down hydraulic pressure threshold value and continue for some time T higher than default3, or the running frequency of converter is less than default minimum running frequency and continuing for some time T4, then control converter stopping；First starts hydraulic pressure threshold value<Second starts hydraulic pressure threshold value<Close down hydraulic pressure threshold value.The invention also discloses a kind of intelligent water supply method.The present invention to the startup of converter and stops control mode and is optimized, can extension device to a certain extent normal service life.
Description
Technical field
The present invention relates to a kind of intelligent water supply device and method.
Background technology
The master that pressurized water supply has been increasingly becoming production, living water is carried out to backend user using the water pump of transducer drive
Mode, this kind of way of supplying water is wanted generally using the Frequency Converter Control strategy of constant pressure water supply, i.e., to keep permanent with water pump water outlet side hydraulic pressure
Being set to target carries out PI or PID control to converter.For example, in dyeing, vapor and water be two requisite
Key element.Enterprise is for energy-conservation, the consideration of reduces cost, it will usually which building a tank will be carried out back using the vapor after complete
Receive and utilize, the water of liquefaction for now reclaiming in tank is that have uniform temperature, in some techniques, the water that reclaimed using these,
Not only water quality is good, and can reduce the heating energy consumption of water, and the expense of certain water is also have saving, exists in economic benefit
Higher feasibility.The scheme for generally adopting is to increase a booster water pump, after being pressurized to the water outlet of tank to the back-end
Supply water, generally according to the output that actual demand controls booster water pump using converter.Fig. 1 shows a kind of adoptable intelligence
Water system, in figure, 1 is tank, 2 is water pipe, 3 is converter, 4 is pressure-detecting device, 5 is booster water pump, 6 is water outlet
Mouth control valve, 3 built-in pi regulator of converter.4 real-time detection water outlet side hydraulic pressure P of pressure-detecting device is simultaneously transferred to PI regulations
Device, as shown in Fig. 2 after water outlet side hydraulic pressure P is compared with default command pressure value Pref by pi regulator as value of feedback
Corresponding frequency instruction f is exported to converter 3, the rotating speed respective change of booster water pump 5, the hydraulic pressure so as to control water outlet side keep
Constant or water flow keeps constant.
At present, research worker is fast for the research of intelligent water supply method is concentrated mainly on the operating control targe of converter
Speed is realized exactly.For converter startup and stop operation that research is less, water of the prior art substantially by arranging
Pressure upper and lower limit is controlled come the startup and stopping for realizing converter, when water outlet side water pressure monitoring value is less than hydraulic pressure lower limit, is then started and is become
Frequency device, when water outlet side water pressure monitoring value is higher than the hydraulic pressure upper limit, then stops converter.
Under actual use environment, the startup of above-mentioned converter and stop control mode tending to cause converter,
The frequent starting of water pump, close down, the normal service life of equipment can be reduced.
Content of the invention
The technical problem to be solved is to overcome prior art not enough, there is provided a kind of intelligent water supply device, pin
Practical situation to the startup of converter and is stopped by control mode is optimized, extension device normally can make to a certain extent
Use the life-span.
The present invention specifically employs the following technical solutions solution above-mentioned technical problem：
A kind of intelligent water supply device, including：
Pump, for conveying after water is pressurized；
Converter, for driving the pump variable-speed operation；
Pressure transducer, samples for the discharge side hydraulic pressure to the pump；
Control unit, for being controlled to the converter, its startup to converter, the control method for stopping are concrete such as
Under：
Start hydraulic pressure threshold value less than default first and maintain a period of time T when side hydraulic pressure sampled value is discharged1, and thereafter
Section time T2Interior, the maximum for discharging side hydraulic pressure sampled value starts hydraulic pressure threshold value not less than default second, then control converter
Start, otherwise, converter does not start；
In converter running, such as there is discharge side hydraulic pressure sampled value and close down hydraulic pressure threshold value and continue one section higher than default
Time T3, or the running frequency of converter is less than default minimum running frequency and continuing for some time T4, then control converter
Stop；
First starts hydraulic pressure threshold value<Second starts hydraulic pressure threshold value<Close down hydraulic pressure threshold value.
Preferably, in converter running, control unit is so that the side hydraulic pressure of discharging of the pump keeps constant pre-
If pressure is controlled to converter for target.
Preferably, described control unit is PI or PID control unit.
Technical scheme below can also be obtained according to identical invention thinking：
A kind of intelligent water supply method, does variable-speed operation by transducer drive pump to convey after water is pressurized；The converter
Startup, method for controlling stopping are specific as follows：
When the discharge side hydraulic pressure sampled value of pump less than the default first startup hydraulic pressure threshold value and maintains a period of time T1, and thereafter
A period of time T2Interior, the maximum for discharging side hydraulic pressure sampled value starts hydraulic pressure threshold value not less than default second, then control becomes
Frequency device starts, and otherwise, converter does not start；
In converter running, the discharge side hydraulic pressure sampled value for pump such as occur is closed down hydraulic pressure threshold value and continues higher than default
A period of time T3, or the running frequency of converter is less than default minimum running frequency and continuing for some time T4, then control change
Frequency device stops；
First starts hydraulic pressure threshold value<Second starts hydraulic pressure threshold value<Close down hydraulic pressure threshold value.
Preferably, in converter running, so that the constant preset pressure of side hydraulic pressure holding of discharging of the pump is
Target is controlled to converter.
Preferably, PI controls or PID control are carried out to converter.
Compared to existing technology, the invention has the advantages that：
The present invention is carried out to the startup of pump variable frequency device in intelligent water supply device and stopping control mode for practical service environment
Optimize, be effectively reduced the startup of unnecessary converter, water pump, so as to the normal use of extension device to a certain extent
Life-span.
Description of the drawings
Fig. 1 is intelligent water supply system example, and wherein, 1 is tank, 2 is water pipe, 3 is converter, 4 is that pressure detecting is filled
Put, 5 be booster water pump, 6 be outlet control valve；
Fig. 2 is pi regulator principle schematic；
Fig. 3 be opened with the penstock short time after again close in the case of water outlet side hydraulic pressure situation of change；
Fig. 4 be with penstock open just commonly use water in the case of water outlet side hydraulic pressure situation of change；
Fig. 5 is the startup of converter and stopping control flow chart in intelligent water supply device of the present invention.
Specific embodiment
Below in conjunction with the accompanying drawings technical scheme is described in detail：
By taking intelligent water supply device shown in Fig. 1 as an example, it is assumed that its used existing converter automatic control program, i.e.,
Discharge side hydraulic pressure sampled value P that the sampling of pressure-detecting device 4 is obtained by control unit and default startup hydraulic pressure threshold value PminCompare
Compared with, once detecting discharge side hydraulic pressure sampled value P is less than Pmin（Or side hydraulic pressure sampled value P is discharged less than PminState reach
Default a period of time）, then control converter startup, and then drive starting mode of pump operating.
But find there is a kind of phenomenon in actual use using the intelligent water supply device of such scheme through numerous studies：
When user opens outlet control valve, and rapid closing, the water pump discharge side hydraulic pressure sampled by its pressure-detecting device is such as
Shown in Fig. 3；It can be seen that according to conventional decision method, then converter and motor can be started, pressurized water supply is carried out,
That is, again rapid after user opens outlet control valve close, converter and motor are activated this moment.At this
Kind in the case of, user be not intended in fact start motor, in order to avoid this kind of the occurrence of, by researching and analysing, contrast
When user opens outlet control valve, water is just being commonly used（The operation of rapid closing is not carried out）Pressure change（Such as Fig. 4 institutes
Show）.It was found that there is a feature：When user opens the difference of the turn-off time of outlet control valve, its pressure transducer institute
The discharge lateral pressure of sampling is also different, and its concrete rule is the time interval and pressure between outlet control valve open and close
The peak point Pp of force transducer sampling is relevant（The two is inversely proportional to, shut-off faster, in pipeline, highest hydraulic pressure point Pp is higher）.
The present invention based on this kind of feature, devises the start-up criterion of pump variable frequency device：When the discharge side hydraulic pressure of pump is sampled
Value less than the default first startup hydraulic pressure threshold value and maintains a period of time T1（In order to prevent hydraulic pressure momentary fluctuation from doing detection
Disturb, preferably T1It is more than or equal to 1ms）And a period of time T thereafter2Interior（T2It is preferred that 0.1s～5s）, discharge side hydraulic pressure sampled value
Maximum not less than default second start hydraulic pressure threshold value, then control converter start, otherwise, converter does not start.So
The problems referred to above can be effectively avoided, so as to reduce the startup of unnecessary converter, water pump, extension device to a certain extent
Normal service life.
In intelligent water supply device of the present invention, the startup of converter and stopping control flow are as shown in figure 5, specific as follows：
When user opens outlet control valve, first by the effect of the current water storage static pressure of tank, start water outlet, now press
Sampling pressure of supply water value P of force transducer can decline rapidly, when minimum less than tank for hydrostatic pressure Pmin when and continue one
Section preset time T1, and in a period of time T afterwards2Interior, the maximum Pp of the sampling pressure of supply water of pressure transducer is less than PL
(PL be default second start hydraulic pressure threshold value), also just explanation during this period of time, is not turned off valve or turns down valve
Action（Because the action for closing valve will cause the hydraulic pressure increase in pipeline), then start the operation of transducer drive booster water pump；
If in stipulated time T2Interior, Pp is more than PL, then the action for having shutoff valve door or turning down valve, in such cases frequency conversion are described
Device does not start.
After converter starts, constant pressure water supply is realized by continuous PI or PID dynamic regulations.Can specifically adopt existing each
Control strategy is planted, here is omitted.
When user's water demand amount reduces, the static energy in pipeline meets water demand or without the need for, when using water, using
Family turns down or closes outlet control valve, and now as converter continues to drive booster water pump work, valve is turned down or is closed
Close, therefore the pressure of supply water value in the pipeline of the sampling of pressure-detecting device becomes larger, i.e. the feedback pressure of PI or PID controller
Power becomes larger, when feedback pressure force value is more than command pressure value Pref for setting, the output frequency instruction of PI or PID controller
F starts to reduce, and the rotating speed of booster water pump starts to reduce, and when hydraulic pressure value continuation increase is fed back, frequency instruction f continues to reduce, and works as f
Less than the time T for setting minima fmin and keep setting4Afterwards（Wherein T4Preferably greater than or equal to 1s）, then control converter and stop
Machine.Or, in booster water pump high power work, when user need not use water, outlet valve is closed, then in pipeline
Hydraulic pressure can rise rapidly, now PI or PID controller also have not enough time to by output frequency instruction adjust to minima fmin with
Under, and the hydraulic pressure in pipeline has breached maximum pressure setting value, then tie up more than the situation of maximum pressure setting value in hydraulic pressure
The time T of one section of setting is held3Afterwards（Wherein T3Preferably 1ms～1s, it is the transient wave in order to prevent hydraulic pressure that lower limit chooses 1ms
The dynamic impact produced by detection, it is then in order to be able to the rapid reaction of overpressure situation that the upper limit takes 1s）, intelligence shutdown converter.
Claims (6)
1. a kind of intelligent water supply device, it is characterised in that include：
Pump, for conveying after water is pressurized；
Converter, for driving the pump variable-speed operation；
Pressure transducer, samples for the discharge side hydraulic pressure to the pump；
Control unit, for being controlled to the converter, its startup to converter, the control method for stopping are concrete such as
Under：
Start hydraulic pressure threshold value less than default first and maintain a period of time T when side hydraulic pressure sampled value is discharged1, and thereafter
Section time T2Interior, the maximum for discharging side hydraulic pressure sampled value starts hydraulic pressure threshold value not less than default second, then control converter
Start, otherwise, converter does not start；
In converter running, such as there is discharge side hydraulic pressure sampled value and close down hydraulic pressure threshold value and continue one section higher than default
Time T3, or the running frequency of converter is less than default minimum running frequency and continuing for some time T4, then control converter
Stop；
First starts hydraulic pressure threshold value<Second starts hydraulic pressure threshold value<Close down hydraulic pressure threshold value.
2. intelligent water supply device as claimed in claim 1, it is characterised in that in converter running, control unit so that
The side hydraulic pressure of discharging of the pump keeps constant preset pressure to be controlled converter for target.
3. intelligent water supply device as claimed in claim 1 or 2, it is characterised in that described control unit is PI or PID control list
Unit.
4. a kind of intelligent water supply method, it is characterised in that do variable-speed operation by transducer drive pump to convey after water is pressurized；
The startup of the converter, method for controlling stopping are specific as follows：
When the discharge side hydraulic pressure sampled value of pump less than the default first startup hydraulic pressure threshold value and maintains a period of time T1, and thereafter
A period of time T2Interior, the maximum for discharging side hydraulic pressure sampled value starts hydraulic pressure threshold value not less than default second, then control becomes
Frequency device starts, and otherwise, converter does not start；
In converter running, the discharge side hydraulic pressure sampled value for pump such as occur is closed down hydraulic pressure threshold value and continues higher than default
A period of time T3, or the running frequency of converter is less than default minimum running frequency and continuing for some time T4, then control change
Frequency device stops；
First starts hydraulic pressure threshold value<Second starts hydraulic pressure threshold value<Close down hydraulic pressure threshold value.
5. intelligent water supply method as claimed in claim 4, it is characterised in that in converter running, so that the pump
Discharging side hydraulic pressure keeps constant preset pressure to be controlled converter for target.
6. intelligent water supply method as described in claim 4 or 5, it is characterised in that PI controls or PID control are carried out to converter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611073119.7A CN106499009B (en) | 2016-11-29 | 2016-11-29 | A kind of intelligent water supply device and method |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201611073119.7A CN106499009B (en) | 2016-11-29 | 2016-11-29 | A kind of intelligent water supply device and method |
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| CN106499009A true CN106499009A (en) | 2017-03-15 |
| CN106499009B CN106499009B (en) | 2019-05-24 |
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ID=58329124
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108894285A (en) * | 2018-07-26 | 2018-11-27 | 浙江达峰科技有限公司 | A kind of constant pressure Floating Ball Liquid Level reaches the determination method of setting value |
| CN109231316A (en) * | 2018-11-28 | 2019-01-18 | 杭州和利时自动化有限公司 | A kind of control system of sewage disposal system |
| CN110836746A (en) * | 2018-08-16 | 2020-02-25 | 宁波方太厨具有限公司 | Method and device for safely detecting water flow in closed pipeline |
| CN111219856A (en) * | 2019-12-30 | 2020-06-02 | 上海真聂思楼宇科技有限公司 | Air treatment equipment intelligent optimization group control device and method based on 5G communication |
| CN113757091A (en) * | 2020-06-05 | 2021-12-07 | 浙江大元泵业股份有限公司 | Control method for reducing frequent starting of pressure control type water pump |
| CN114281119A (en) * | 2021-12-23 | 2022-04-05 | 无锡汇田水务科技有限公司 | Water pressure control method, secondary water supply system, electronic device, and storage medium |
| CN114483558A (en) * | 2022-01-04 | 2022-05-13 | 威乐(中国)水泵系统有限公司 | A state control method, device and system for a water pump |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108894285A (en) * | 2018-07-26 | 2018-11-27 | 浙江达峰科技有限公司 | A kind of constant pressure Floating Ball Liquid Level reaches the determination method of setting value |
| CN110836746A (en) * | 2018-08-16 | 2020-02-25 | 宁波方太厨具有限公司 | Method and device for safely detecting water flow in closed pipeline |
| CN109231316A (en) * | 2018-11-28 | 2019-01-18 | 杭州和利时自动化有限公司 | A kind of control system of sewage disposal system |
| CN111219856A (en) * | 2019-12-30 | 2020-06-02 | 上海真聂思楼宇科技有限公司 | Air treatment equipment intelligent optimization group control device and method based on 5G communication |
| CN113757091A (en) * | 2020-06-05 | 2021-12-07 | 浙江大元泵业股份有限公司 | Control method for reducing frequent starting of pressure control type water pump |
| CN114281119A (en) * | 2021-12-23 | 2022-04-05 | 无锡汇田水务科技有限公司 | Water pressure control method, secondary water supply system, electronic device, and storage medium |
| CN114281119B (en) * | 2021-12-23 | 2022-11-04 | 无锡汇田水务科技有限公司 | Water pressure control method, secondary water supply system, electronic device, and storage medium |
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| CN114483558A (en) * | 2022-01-04 | 2022-05-13 | 威乐(中国)水泵系统有限公司 | A state control method, device and system for a water pump |
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