Foreword:
In the fuel depot management production process, the feeding pump in the entire production system is the daily average frequency of use highest equipment, but the majority of fuel depots feeding pump starts the way all to use the star triangle to start, because the star triangle start way enlarges to the electrical machinery and the oil pump impact, creates the oil pump bearing to touch damages the acceleration and the noise increases and so on many weakness, below for this company when transformation coal Qinhangdao storage and transport center Austria fuel depot oil transfer, obtained arrives field data.
Essential character: Frequency changer feeding pump energy conservation
First, Austria fuel depot 37KW feeding pump present movement condition
Melts the Austria fuel depot feeding pump to be composed by 4 37KW vertical oil pump, mainly undertakes 4 to work Taichung's 8 attires oils spot to come to the tank truck to carry on the measurement to install the oil work. Each attire oil pipeline design delivery rate for each hour 60 cubic, 37KW feeding pump each hour current capacity is 180 cubic, a feeding pump undertakes a work table 2 attires oils 注油 work duty (respectively is 1st valve and 2nd valve, valve opens to tank truck 注油); But actual produces in the operation the major part time only to open a delivery valve gate, two attires oil cars are very few with the fashionable clothing oil, originally designs 37KW when the feeding pump is at the same time two attires oil cars the work designs, when opens a valve, also must completely shoulder the work, completely shoulders when the work the oil pump delivery rate can arrive each hour 180 cubic, finally when actual use only then needs its 1/3 current capacity to be able to satisfy the production request, through to the entire oil transfer system principle of work analysis, the original feeding pump movement principle has following several problems:
1st, 37KW feeding pump delivery rate oversized, when opens a delivery valve only needs the feeding pump 1/3 current capacity, the feeding pump each time opens all the full load 180 cubic outputs movements, such oil pump and the pipeline have the very big differential pressure, forms 涡the pressure, the pipeline differential pressure enlarges when causes the electrical machinery load to increase, the electric current rise, creates the electrical energy waste.
2nd, the oil pump big and the actual pipeline transports the volume as a result of the output volume to be small, under such working conditions, in the feeding pump movement has had the massive useless power losses, also greatly reduced the feeding pump electrical machinery service life, enlarges the maintenance of equipment cost.
Above synthesis work background, it is necessary to carry on the energy conservation movement to the feeding pump electrical machinery system to promote, moves the feeding pump using the frequency changer velometer, by obtains the current capacity and the pressure may move, comes the automatic control feeding pump system according to the actual demand current capacity and the pressure.
Second, the feeding pump system uses the frequency conversion velocity modulation movement the energy conservation technology principle
The oil pump starts in the original operational factor for the electrical machinery take the 50Hz revolution, the rotational speed as the 1420r/min extension, the delivery rate 180 cubic, the rotational speed and the current capacity pressure has the direct ratio, like the chart shows:

Chart 1: Feeding pump principle of work minute booklet

We may see from on chart, through the oil pump electrical machinery rotational speed change, the current capacity also reduces along with the rotational speed reduces, therefore only has the use frequency changer to be able to cause the oil pump electrical machinery the rotational speed to turn freely may move, simultaneously also causes the oil pump the current capacity and the pressure may move, achieves the existing production technological requirement through the frequency conversion adjustment. We use in Beijing to reach the water chestnut branch LK600P series oil pump special-purpose frequency changer which the water chestnut branch electricity limited company produces, enhances the feeding pump the operational factor, moreover fully realizes the current capacity and the pressure using the frequency changer velocity modulation function may move, to wilfully adjusts the electricity saving turning point 速来 to achieve the goal, simultaneously also gets up saves the electrical energy, the seat of monarchical government long oil pump electrical machinery service life, the environmental protection energy conservation is this project original intention.
Feeding pump through frequency conversion movement energy conservation basis? --- The frequency conversion principle of work does not make the detailed introduction in this, we carry on the contrast through the under graph to be allowed to see, time frequency conversion movement electrical machinery rotational speed change, electrical machinery load current also along with change. Certainly because the electrical machinery rotational speed reduces the frequency conversion output voltage also immediately to reduce, through stepping down of voltage, the oil pump load current also similarly reduces. Under states the data is this company the actual data which measured in the scene electrical machinery movement. Chart 2: The table is 37KW loses time the oiler frequency movement electrical machinery load current, table 1: For 37KW feeding pump in frequency conversion movement time oil pump electrical machinery rotational speed, electrical machinery running current as well as in free rotational speed time current capacity change.

Chart 2: 37KW loses time the oiler frequency movement electrical machinery load current

Table 1: 37KW feeding pump in frequency conversion movement time different speed load current and current capacity change value.
When oil pump electrical machinery model labor frequency movement electric current
(A) when frequency conversion movement the electrical machinery transfers intensively
(Hz. r/min) oil pump net load electric current
(A) oil pump delivery rate
(Cube)



Y225M-4
37KW


74A 50Hz-1420r/min 74A 173
45Hz-1278r/min 61A 158
40Hz-1136r/min 51A 123
37Hz-1050r/min 49.5A 117
35Hz-994r/min 48A 110
33Hz-937r/min 47.5A 107
30Hz-852r/min 45A 90
25Hz-710r/min 43A 71
20Hz-568r/min 43A 40

Field data: Melts a Austria fuel depot 37KW oil pump to supply a work table two notes oil valves work, a note oil valve design delivery rate is 60 cubic, when two simultaneously open, the current capacity can satisfy the production request in 120 cubic, how realizes a note oil valve to open, the frequency changer only must output 60 cubic accurate current capacities? In below solution detailed explanation. When is a tank truck carries on 注油 the work, the frequency changer take the 25Hz revolution, the electrical machinery electric current as 43A, may save electric current 51A, the electricity saving rate below 60%. When turns on two notes oil valves is two tank trucks 注油, the frequency changer operating frequency is 35Hz, electrical machinery electric current 48A, saves electric current 26A, the electricity saving rate below 40%.
Tabulates from on with the field data comes the minute compromise coal Qinhangdao storage and transport center Austria fuel depot existing feeding pump principle of work, I may see frequency changer when movement oil pump the function, controls the feeding pump through the frequency conversion the electrical machinery rotational speed, causes the oil pump to output a reasonable current capacity and the pressure satisfies the production request, simultaneously also greatly falls the bottom electrical machinery the load current, the energy conservation is extremely obvious.
Third, frequency changer control mode
The frequency changer function is provides the variable frequency for the electrical machinery the power source, realizes the electrical machinery stepless speed regulation, thus causes the pipe network flowing tubing head pressure continuously to change. The pressure changes the delivering duty is examines the pipe network the current capacity and the pressure, current capacity and the pressure hypothesis unit provides meets the user need for the system the current capacity and the pressure expected value. The current capacity and the pressure hypothesis signal signal input the frequency changer after 4-20mA current feedback to pass through the frequency changer interior PID control procedure again the computation, outputs for a frequency changer speed control signal, the frequency changer receives when the 4-20mA electric current signal starts to work, first starts the feeding pump electrical machinery, enables the pipe network current capacity flowing tubing head pressure to achieve supposes the definite value, afterwards the frequency changer output frequency when arrives the apex along with the current capacity and the pressure, the frequency changer rotational speed starts to drop, until the maintenance pipe network pressure and the current capacity transportation in conforms to the production requirement to need in the predetermined value. When loses the oil mass increases or opens two delivery valves the pipe network pressure to weaken, the pressure changes delivering to send in this signal processing 4-20mA signal the frequency changer, (note: The frequency changer is according to the 4-20mA magnitude of current size decided the output frequency the size, the frequency size is electrical machinery rotational speed Gao Yudi), the frequency changer frequency starts to rise again, causes the frequency changer the output frequency rise, the oil pump rotational speed enhancement, the current capacity and the pressure corresponding rise, if 注油 the delivery rate increases very much, the frequency changer output frequency maximizing 50Hz, the above will rest on, will set at the PID control through frequency conversion in to be able to cause the entire wrap oil supply system operational to be stronger, greatly will reduce the work density.
Because the entire Austria fuel depot electrical system uses on the position machine collection control, the feeding pump electrical machinery selects the soft start method to start, the feeding pump start, stops, respectively and machine side controls be the common control, the control desk is two government officials misses solenoid valve, undertakes using the solenoid valve switch for the tank truck 注油 work, the government official miss solenoid valve has the current capacity measurement and the pressure changes delivers the function, can provide 4 - 20MA for the frequency changer to change delivers the signal output, the pressure changes delivers the value to be possible freely to establish the size, establishes changes delivers the value to correspond the 4-20MA output. When the water chestnut branch frequency changer 4-20mA signal input connection receives the pressure changes the delivering transmission the electric current signal, according to the supply oscillator size again the PID control computation which sets through the frequency changer in, can automatically completely cause the feeding pump in the current capacity pressure which prearranges to work, achieves this production line the production technological requirement.
Fourth, system plan
In the fuel depot management production process, the feeding pump belongs to the count for much production equipment in the overall system, requests the frequency changer to be able the long time continuous working, should have outside the performance must have the extremely high reliability, in understood the scene the production craft characteristic and unifies this design proposal, when this system design should have adapts the scene serviceability, combines versatile and the original electrical system mutually compatible, achieves is invariable according to the original control characteristic; Below when this system design has the function:
1st, the frequency conversion system and the driving force cabinet labor frequency soft starter system can manual freely cut. Once the frequency conversion system appears some kind of breakdown, may manual cut the driving force cabinet the labor frequency soft start, when frequency conversion system service period, the original soft starter system can normally safeguard the feeding pump the movement work, satisfies the fuel depot the regular production.
2nd, the frequency conversion system revolution frequency adjustment selects the PID closed-loop control link method, changes according to the current capacity pressure delivers 4-20mA the letter to decide the frequency changer the output frequency, safeguards the oil transfer system the safe operation to cause the entire wrap system like this more convenient operational, the intelligent automation to be stronger.

Chart 3: Frequency conversion feeding pump wiring diagram

3rd, considered the scene the working conditions and the equipment security, the frequency conversion control cabinet kneading board not suitably establishes the excessively many graphic display device, only disposes the soft starter and the frequency conversion change-over switch, the movement indicating lamp, the frequency conversion movement breakdown lights, the frequency conversion operation demonstration kneading board, causes the frequency changer the movement parameter, the electrical machinery electric current, the electrical machinery rotational speed to be clear, enormously has facilitated the scene operator's operation and to the equipment running status monitoring.
4th, the frequency conversion system establishes 6 passwords, may the frequency changer movement parameter locking protection, guarantee the frequency conversion oil transfer system not to create under the artificial misoperation the feeding pump engine off, the realization system continuously steadily moves.
5th, the frequency changer uses independently matches the line power supply, ceases the electromagnetism mutually to disturb to the equipment, guarantees the equipment the safe operation.
6th, the frequency conversion system implemented to the feeding pump electrical machinery softly opens, softly stops, reduces in the start process to the electrical network impact, at the same time the improvement power supply quality also lengthened the feeding pump electrical machinery maintenance maintenance cycle, after because the use frequency conversion with originally compared the electrical machinery rpm drop, the low speed movement to the oil pump shaft, the bearing attrition degree reduced, this greatly will lengthen the feeding pump the bearing, the mechanical seal and so on the vulnerable life.

Fifth, project construction cost
This project is composed by 4 37KW feeding pump, the frequency changer selects 4 37KW the water chestnut branch LK600P series oil pump special-purpose frequency changer, entire project construction cost following table:
Serial number product model quantity unit price RMB total amount RMB project total construction cost RMB
1 water chestnut branch LK600P-037T4
37KW frequency changer 417800.0071200.00


129900.00
2 frequency conversion cabinets GPT 44300.0017200.00
3 air switches, the contact device, demonstrate the kneading board,
Change-over switch, indicating lamp, intelligent feedback card 45300.0021200.00
4 pilot wires and host electrical machinery electric cables 112000.0012000.00
5 scenes wiring execute labor cost 18300.008300.00

Sixth, investment cost 收回�?br> 4 feeding pumps according to work every day 12 hours computations, according to the actual average electricity saving rate 40% (this data for other projects 实�, does not represent this project accurate data) 4 months to be possible to recycle all investments.

Seventh, concluding remark
Has managed in the entire fuel depot production center, the feeding pump is the entire system main production link, also is in the entire operation system with the TV University household, carries on the energy conservation to the feeding pump to fall consumes has the certain necessity, current carries on the effective technical way to the feeding pump which the energy conservation falls consumes uses the frequency changer, improves the feeding pump efficiency using the frequency conversion velocity modulation function. In the overall system implementation movement process, the frequency changer not only carries on a time of intelligence to the overall system to rise extremely outside, causes the entire production operation process to manifest the human nature, the intelligent automation, simultaneously also has the huge economic efficiency, for instance the oil pump use cycle seat of monarchical government is long, maintenance cost reduction and so on, believed this project 受益�?has the experience compared to the project implementation.

Author: Open Xiaolian
Position: Electrical engineer
Presently is in office to: In Beijing reaches the water chestnut branch electricity science and technology limited company
Telephone: 010-52200133
Mailbox: 3365115@163.com