CN104595168A - Method for controlling water pump frequency conversion based on tail end constant impedance - Google Patents
Method for controlling water pump frequency conversion based on tail end constant impedance Download PDFInfo
- Publication number
- CN104595168A CN104595168A CN201410728977.5A CN201410728977A CN104595168A CN 104595168 A CN104595168 A CN 104595168A CN 201410728977 A CN201410728977 A CN 201410728977A CN 104595168 A CN104595168 A CN 104595168A
- Authority
- CN
- China
- Prior art keywords
- tail end
- frequency conversion
- resistance value
- pump
- constant impedance
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Abstract
The invention discloses a method for controlling water pump frequency conversion based on tail end constant impedance. According to the main technical scheme, the water pump frequency conversion is controlled by keeping a tail end impedance value St constant, the impedance is the ratio of differential pressure to the flow square, and the impedance value is obtained by monitoring the tail end pressure value and the flow value; then, according to the obtained impedance value, when the actual-running tail end impedance value is larger than the maximum value within the set section, the rotating speed of a frequency conversion pump is reduced so as to turn down the flow; when the actual-running tail end impedance value is smaller than the minimum value within the set section, the rotating speed of the frequency conversion pump is increased so as to turn up the system flow. According to frequency conversion adjustment, working points are changed by means of a characteristic curve changing method, the method is an ideal adjustment method, and meanwhile the working frequency of a power source is changed through a frequency converter so that stepless speed regulation of an alternating current motor can be achieved.
Description
Technical field:
[the present invention relates to the method for controlling frequency conversion of water pump, especially control the method for pump variable frequency based on end constant impedance.
Background technique:
[as one of current consuming apparatus that China's industrial or agricultural field is main, water pump is widely used in the fields such as building, urban water supply and sewerage, petrochemical industry, power industry, thermal power generation, shipping industry and metallurgical mining, and its power consumption accounts for about 20% of national gross generation.In the actual measurement of large public building heat supplying air conditioning power consumption, the power consumption of water Pumps & Fans accounts for about 60% ~ 70%.The peak efficiency of current water pump generally can reach 75% ~ 85%, but in running, the efficiency of most of water pump is between 30% ~ 50%, more much lower than developed country water pump efficiency, and energy consumption waste is relatively more serious, and operational efficiency has larger room for promotion.
The basic principle of variable-frequency control technique is the relation be directly proportional to working power incoming frequency according to motor speed: n=60 f (1-s)/p, (in formula, n, f, s, p represent rotating speed, incoming frequency, motor slip ratio, motor pole logarithm respectively); The object changing motor speed is reached by changing motor working power frequency.Known by hydromechanical fundamental law: pump apparatus all belongs to asquare torque load, its rotating speed n and flow Q, pressure H and air horsepower P has following relation: Q ∝ n, H ∝ n
2, P ∝ n
3; That is, flow is directly proportional to rotating speed, square being directly proportional of pressure and rotating speed, cube being directly proportional of air horsepower and rotating speed.Adopt variable frequency adjustment simultaneously, can wearing and tearing be alleviated, reduce the noise of pump, increase the service life.
The control mode of current pump variable frequency enclosed variable flow pumping system mainly contains temperature difference control mode, pressure reduction control mode, minimum resistance control mode and other control modes etc.The differential pressure control method of pump variable frequency compares fast and stable, most widely used general; Confession backwater main constant pressure difference control mode is simple but energy consumption is comparatively large, and constant pressure at the end circle control mode energy consumption is less but end and pressure difference are not easily fixed, and adjustability is poor; Minimum resistance control method energy consumption is minimum, but requires higher to end valve, and need monitor most of valve, higher to control overflow; Therefore, under current situation, a kind of blanket control is simple, energy consumption is lower new pump variable frequency control technique is proposed and unit number control technology very necessary.
Summary of the invention:
[for the situation that present pump variable frequency controls, the present invention proposes a kind of method controlling pump variable frequency based on end constant impedance, its technological scheme is at input end resistance value St given in advance, then pump motor is regulated by the controller of connection adjustor according to given resistance value St, pump motor is through the rotating speed of variable frequency adjustment motor, obtain final current, at end, differential pressure pickup and flow transducer are set, pass through measurements and calculations, obtain actual resistance value St ', again feed back to input end and regulate.
Frequency variator installs power frequency shunting device additional simultaneously, is controlled to disconnect and close, ensure system reliability by high voltage isolator group.
Regulator can carry out closed-loop adjustment according to feeding back the resistance value obtained, and enables system reach self adaption state.
Can add up the flow of water pump in multiple frequency conversion situation and energy consumption data, draw the interval of optimum resistance value, make the input of resistance value given in advance more have basis.
Beneficial effect:
Variable frequency adjustment is exactly that the method for utility curve change is to change operation point, it is more satisfactory a kind of regulating method, change by frequency variator the stepless speed regulation that the frequency of okperation of power supply can realize AC motor simultaneously, and based on the method that end constant impedance controls pump variable frequency control simple, energy consumption is lower.
Accompanying drawing illustrates:
Fig. 1 is end constant impedance control mode control flow chart.
Fig. 2 is power frequency Bypass Control schematic diagram.
Embodiment:
[for better the present invention to be described, be convenient to understand technological scheme of the present invention, typical but non-limiting embodiment of the present invention is as follows.
At the resistance value S that input end is given in advance
t, then pass through the controller of connection adjustor according to given resistance value S
tregulate pump motor, pump motor, through the rotating speed of variable frequency adjustment motor, obtains final current.
Differential pressure pickup and flow transducer are set at end, by measurements and calculations, obtain actual resistance value S
t', again feed back to input end and regulate.
By Fig. 2, for frequency variator installs power frequency shunting device additional simultaneously, when frequency variator is abnormal, frequency variator is out of service, runs under motor straight can being allowed to connect be manually switched to power frequency.Power frequency bypass is made up of S1, S2 and S3 tri-high voltage isolators.Require that S2 can not close with S3 simultaneously, mechanically realize interlocking.During converting operation, S1 and S2 closes, and S3 disconnects; During power frequency operation, S3 closes, S1 and S2 disconnects, and fully can ensure the reliability of system.
Claimant states, above content is in conjunction with concrete preferred implementation further description made for the present invention, can not assert that specific embodiment of the invention is confined to these explanations.For general technical staff of the technical field of the invention, without departing from the inventive concept of the premise, some simple deduction or replace can also be made, all should be considered as belonging to protection scope of the present invention.
Claims (4)
1. control a method for pump variable frequency based on end constant impedance, it is characterized in that: at the resistance value S that input end is given in advance
t, then pass through the controller of connection adjustor according to given resistance value S
tregulate pump motor, pump motor, through the rotating speed of variable frequency adjustment motor, obtains final current, arranges differential pressure pickup and flow transducer at end, by measurements and calculations, obtains actual resistance value S
t', again feed back to input end and regulate.
2. the method controlling pump variable frequency based on end constant impedance according to right 1, is characterized in that: frequency variator installs power frequency shunting device additional simultaneously, is controlled to disconnect and close, ensure system reliability by high voltage isolator group.
3. the method controlling pump variable frequency based on end constant impedance according to right 1, is characterized in that: regulator can carry out closed-loop adjustment according to feeding back the resistance value obtained, and enables system reach self adaption state.
4. the method controlling pump variable frequency based on end constant impedance according to right 1, it is characterized in that: can add up the flow of water pump in multiple frequency conversion situation and energy consumption data, draw the interval of optimum resistance value, make the input of resistance value given in advance more have basis.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410728977.5A CN104595168A (en) | 2014-12-03 | 2014-12-03 | Method for controlling water pump frequency conversion based on tail end constant impedance |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410728977.5A CN104595168A (en) | 2014-12-03 | 2014-12-03 | Method for controlling water pump frequency conversion based on tail end constant impedance |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN104595168A true CN104595168A (en) | 2015-05-06 |
Family
ID=53121148
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410728977.5A Pending CN104595168A (en) | 2014-12-03 | 2014-12-03 | Method for controlling water pump frequency conversion based on tail end constant impedance |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104595168A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107305055A (en) * | 2016-04-18 | 2017-10-31 | 上海统力控制技术有限公司 | A kind of frequency-changing control system of water pump of central air conditioner |
| WO2020007309A1 (en) * | 2018-07-05 | 2020-01-09 | 濮阳市百福瑞德石油科技有限公司 | Monitoring, prevention and management method for preventing drill pump from pump suffocation and misoperation, and pump pressure protection system therefor |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6019988A (en) * | 1983-07-12 | 1985-02-01 | Toshiba Corp | Pump control device |
| JPH11270488A (en) * | 1998-03-24 | 1999-10-05 | Kawamoto Pump Mfg Co Ltd | Automatic water supply system |
| CN102383466A (en) * | 2011-11-10 | 2012-03-21 | 渤海大学 | High-efficiency cluster type water pump system with constant pressure and variable flow and operation control method |
| CN202266398U (en) * | 2011-09-28 | 2012-06-06 | 河南宝舜化工科技有限公司 | Frequency conversion adjustment device for high-pressure ammonia water pump |
| CN202298755U (en) * | 2011-11-10 | 2012-07-04 | 渤海大学 | Efficient cluster water pump system for constant-voltage converting quantities |
-
2014
- 2014-12-03 CN CN201410728977.5A patent/CN104595168A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6019988A (en) * | 1983-07-12 | 1985-02-01 | Toshiba Corp | Pump control device |
| JPH11270488A (en) * | 1998-03-24 | 1999-10-05 | Kawamoto Pump Mfg Co Ltd | Automatic water supply system |
| CN202266398U (en) * | 2011-09-28 | 2012-06-06 | 河南宝舜化工科技有限公司 | Frequency conversion adjustment device for high-pressure ammonia water pump |
| CN102383466A (en) * | 2011-11-10 | 2012-03-21 | 渤海大学 | High-efficiency cluster type water pump system with constant pressure and variable flow and operation control method |
| CN202298755U (en) * | 2011-11-10 | 2012-07-04 | 渤海大学 | Efficient cluster water pump system for constant-voltage converting quantities |
Non-Patent Citations (2)
| Title |
|---|
| 俞震华: "GW级机组凝结水泵变频运行性能分析", 《中国电力》 * |
| 孟娜: "并联水泵变频运行的效率保障技术研究", 《中国优秀硕士学位论文全文数据库 工程科技II辑》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107305055A (en) * | 2016-04-18 | 2017-10-31 | 上海统力控制技术有限公司 | A kind of frequency-changing control system of water pump of central air conditioner |
| CN107305055B (en) * | 2016-04-18 | 2019-09-20 | 上海统力控制技术有限公司 | A kind of frequency-changing control system of water pump of central air conditioner |
| WO2020007309A1 (en) * | 2018-07-05 | 2020-01-09 | 濮阳市百福瑞德石油科技有限公司 | Monitoring, prevention and management method for preventing drill pump from pump suffocation and misoperation, and pump pressure protection system therefor |
| US11391103B2 (en) | 2018-07-05 | 2022-07-19 | Puyang Baifu Reide Petroleum Science And Technology Company Limited | Monitoring, prevention and management method for preventing drilling pump from pump suffocation and misoperation, and pump pressure protection system therefor |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102367793A (en) | Efficient method and pump valve integrated energy-saving device for water pump | |
| CN102116043A (en) | Frequency conversion constant-pressure water supply system and control method thereof | |
| CN104153425A (en) | Constant-pressure water supply system | |
| CN103452824A (en) | Fan and water pump energy saving system adopting minimum power algorithm based on flow-power curve | |
| CN202001348U (en) | Frequency conversion control system of fan | |
| CN104534628A (en) | Control method and system for variable-frequency cooling water pump | |
| CN103266646A (en) | Variable frequency variable pressure water supply implementation method and variable frequency variable pressure water supply implementation device | |
| CN105157177B (en) | Method for controlling outlet water temperature of cooling tower according to outdoor air state | |
| CN202579138U (en) | Variable frequency power-saving control system of circulating pump | |
| CN104595168A (en) | Method for controlling water pump frequency conversion based on tail end constant impedance | |
| CN203857618U (en) | Self-adaptive throttle control equipment for water cooling unit freezing pump of central air conditioner | |
| CN103195522B (en) | Frequency conversion control method of circulating water pumps of two steam turbine generator sets | |
| CN102661284A (en) | Energy-saving running control system and method for tunnel construction ventilation system | |
| CN203081721U (en) | Water pump energy-saving system | |
| CN203362480U (en) | Direct-cooling cycle-type variable-frequency speed control system | |
| CN203256848U (en) | Water supply network integrated control system | |
| CN203560068U (en) | Constant flow intelligent power-saving protection control system based on three water pumps | |
| CN205332903U (en) | Industry refrigeration cycle water system | |
| CN109191018A (en) | A kind of more pump energy saving management methods of water factory | |
| CN203948272U (en) | A kind of pump energy saving arrangements for speed regulation | |
| CN101363446B (en) | Power-saving device of blower fan water pump | |
| CN204620659U (en) | Cooling recirculation system | |
| CN103398370A (en) | 2*55MW utility boiler feed water system | |
| CN106989478B (en) | Isobaric frequency conversion control method and device applied to large and small parallel chilled water pumps in hospital | |
| CN207795314U (en) | A kind of online indirect air cooling high back pressure thermal power plant unit backpressure control system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20150506 |