CN201083194Y - Air compressor frequency conversion energy-saving device - Google Patents
Air compressor frequency conversion energy-saving device Download PDFInfo
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- CN201083194Y CN201083194Y CNU200720074646XU CN200720074646U CN201083194Y CN 201083194 Y CN201083194 Y CN 201083194Y CN U200720074646X U CNU200720074646X U CN U200720074646XU CN 200720074646 U CN200720074646 U CN 200720074646U CN 201083194 Y CN201083194 Y CN 201083194Y
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- saving device
- frequency variator
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Abstract
The utility model relates to a frequency conversion energy-saving device for an air compressor, comprising a frequency transformator, a pressure transducer, a pressure regulator and a pressure given potentiometer; an input terminal of a main circuit of the frequency transformator is connected with a power frequency power supply, an output terminal of the main circuit is connected with a primary starting unit of the air compressor; the pressure given potentiometer is connected to the frequency transformator, the pressure transducer is connected with the pressure regulator which is also respectively connected with the frequency transformator and the pressure given potentiometer. In addition, a single-pole double-throw isolating knife switch is further arranged between the output terminal of the main circuit of the frequency transformator and the primary starting unit of the air compressor. Therefore, the frequency conversion energy-saving device for an air compressor of the utility model can automatically regulate the operating frequency of a main motor of the air compressor according to a pressure signal and ensure that the rotating speed of the main motor varies with the load, thereby having the advantages of reducing the energy consumption of the air compressor and guaranteeing the safe operation of the system.
Description
Technical field
The utility model relates to the control gear of air compressor, relates in particular to a kind of air compressor frequency converting and energy saving device.
Background technique
At present, most of air compressor unit adopt ac three-phase asynchronous motor to drive, and power supply frequency is the 50Hz power frequency, and the Starting mode of main motor is " star-triangle " reduced-voltage starting mode.Balance between main motor output power and the load power adopts the load or unload mode to be achieved.The characteristics of this mode are to control air compressor work according to the variation of air pressure.In case promptly air pressure is lower than the setting value of rebound pressure, air compressor enters the load operating mode, and the stepper motor in the unit cuts out bleed valve just with INO at this moment, and air compressor just puts into high gear full tolerance to system's air feed.If air pressure is higher than the setting value of release pressure, air compressor will enter the unloading running state, and the interior stepper motor of unit this moment just cuts out suction valve, will separate the cylindrical shell blowdown piping by bleed valve and open, its pressure is descended, and air compressor continues with zero tolerance operation.
The load or unload control mode makes the pressure of pressurized gas fluctuate back and forth between maximum value and minimum value.Minimum value is the minimum that guarantees ordinary production.But, for the continuity that guarantees to use, present control mode be frequently with the pressure-loaded of air compressor to maximum value.The energy that difference consumed is so between the two wasted fully.When pressure reached maximum value, the air compressor unloading was higher than peaked pressure portion and falls to airborne release by pressure-relief valve in the system, cause waste of energy.Load variations is big more, it is frequent more to add unloading, and energy consumption is just big more.
For a long time, the difficult problem of air compressor high energy consumption, low output is never solved effectively.By the frequency-changing pressure stabilizing speed regulating control, can realize cutting down the consumption of energy 20%, and can avoid unit frequently to be hit, prolong the working life of unit.But the original action relationships with the protection that contains the electric control system that microprocessor controller is a basic design and the operating conditions of unit, main motor overheating protection, Pressure testing, temperature control, abnormal state, pressure control valve of air compressor is close.Its core technology is that manufacturing firm is proprietary, can not be open to the user.Therefore, how under the situation that does not change original control system, the relation of handling both well will be extremely important.
The model utility content
The purpose of this utility model is for providing a kind of air compressor frequency converting and energy saving device, this device can be regulated the frequency of okperation of air compressor master motor automatically under the condition of the original intelligent control system of complete reservation air compressor, main motor speed is changed, to reduce the energy consumption of air compressor with load variations.
To achieve these goals, air compressor frequency converting and energy saving device of the present utility model adopts following technological scheme:
A kind of air compressor frequency converting and energy saving device comprises frequency variator, pressure transducer, pressure regulation instrument, pressure given potentiometer; The main circuit input end of described frequency variator connects power frequency supply, and the main circuit output terminal connects the former start unit of air compressor; Described pressure given potentiometer is connected on the frequency variator, and described pressure transducer is connected with pressure regulation instrument, and pressure regulation instrument is connected with the pressure given potentiometer with frequency variator respectively again.
Like this, when the pressure signal that pressure transducer detects is regulated through pressure regulation instrument, and relatively form the frequency adjustment signal in the back with the pressure given potentiometer, the frequency adjustment signal is input in the frequency variator, frequency variator then according to the power supply of frequency adjustment signal output corresponding frequencies, is made corresponding variation thereby control main rotating speed of motor with the load number.Therefore, adopt technique scheme, this air compressor frequency converting and energy saving device will be regulated the frequency of okperation of air compressor master motor automatically according to pressure signal, and main motor speed is changed with load variations, thereby have the advantage of the energy consumption that reduces air compressor.
In addition, in order to make pneumatics function switch operating under frequency conversion and power frequency dual mode, in the described further improvement of the utility model, connect by the single-pole double throw disconnection switch between the main circuit output terminal of described frequency variator and the former start unit of air compressor, two closing positions of described single-pole double throw disconnection switch mains side connect the main circuit output terminal of power frequency supply and frequency variator respectively, and single-pole double throw disconnection switch load side connects the former start unit of air compressor.Like this,, can be manually switched to the power frequency mode, air compressor is worked under the power frequency condition if frequency-changing control system breaks down.
Automatically cut off the electricity supply when overcurrent fault occurring in frequency variator inside and cut off the electricity supply at on-load just often, described the utility model connects by three-phase breaker between described main circuit of converter input end and the power frequency supply in further improving.
In order to realize the variable frequency starting of air compressor frequency converting and energy saving device, described frequency variator also is connected by the auxiliary contact of often opening of the corner connection tentaculum in the former start unit of converting operation throw over switch and air compressor.
For to the cooling of air compressor master motor, also include the main frame cooling fan, described main frame cooling fan is connected with power supply by A.C. contactor.
Because frequency variator is when low-frequency operation, heat is bigger, for to the frequency variator cooling, to guarantee the normal operation of frequency variator, also includes the frequency variator cooling fan, and described this frequency variator cooling fan is connected with the 220V power supply by single-phase circuit breaker.
In order to realize the demonstration of main signal, described frequency variator also is connected with two auxiliary reclays, and frequency conversion trouble signal tutorial light and converting operation signal lamp, and described two auxiliary reclays are connected with power supply by single-phase circuit breaker.
Adopt technique scheme, air compressor frequency converting and energy saving device of the present utility model has following advantage:
1, regulates the control function automatically, air compressor adopts frequency-changing pressure stabilizing control, and promptly the pressure signal that provides according to the pressure regulation instrument automatic regulating system is regulated the output speed of frequency variator, holding torque, rotating speed stable, the basic operating mode of eliminating load or unload has the advantage of saving energy consumption.
2, have frequency conversion, two kinds of methods of operation of power frequency, when frequency-changing control system breaks down, can by frequency variator cashier's office in a shop the single-pole double throw disconnection switch switch to the power frequency operation mode rapidly reliably.
3, the double-throw disconnection switch has been stopped the possibility that causes the major loop of power frequency or frequency conversion dual mode to be connected simultaneously because of the control system misoperation.
4, intactly keep original power frequency star-triangle reduced-voltage starting mode, satisfied the condition of frequency variator soft start simultaneously.
Description of drawings
Below in conjunction with the drawings and specific embodiments the utility model is elaborated:
Fig. 1 is a circuit diagram of the present utility model;
Fig. 2 is the schematic representation of frequency variator cabinet;
Fig. 3 is the rear view of Fig. 2;
Embodiment
In the present embodiment, described air compressor adopts the phase asynchronous main motor driving of 380V, 132KW, and power supply frequency is the 50Hz power frequency, and main motor adopts " star-triangle " reduced-voltage starting mode.The output power of main motor and the balance between the load power adopt by intelligent controller control, realize in the load or unload mode.
In order to realize that this air compressor is carried out variable frequency energy saving reforming, (the interior equipment of frame of broken lines is existing equipment among the figure) as shown in Figure 1, in conjunction with Fig. 2 and Fig. 3, air compressor frequency converting and energy saving device of the present utility model, comprise frequency variator 100, pressure transducer 200, pressure regulation instrument 300, pressure given potentiometer 400, three-phase breaker 500, single-pole double throw disconnection switch 600.
Wherein, frequency variator 100 adopts the frequency variator of built-in direct current reactor, and such frequency variator 100 has quick response function, can satisfy the fast-changing requirement of system pressure.And this frequency variator 100 also has overcurrent, overvoltage, overheated, under-voltage, open-phase protection function, and promptly when above-mentioned fault took place in system, frequency variator 100 can be out of service automatically immediately.In addition, this frequency variator 100 also has the fault reset function, and promptly frequency variator 100 is detecting external fault or frequency variator when self breaking down, and frequency variator will be blocked, and stop output, and report to the police by fault indicating lamp; The maintenance man then can find failure cause and remove fault according to failure code.The detent torque of this frequency variator 100 is 220%, can bear 150% overcurrent 1 minute, and the working environment limiting temperature is 60 degree, can satisfy the requirement of air compressor Environmental Conditions fully.This frequency variator 100 is installed in the frequency variator cabinet.
The L1 of frequency variator 100 main circuit input ends, L2, L3 terminal are connected with the 380V ac power supply by three-phase breaker 500, the three-phase breaker 500 of present embodiment employing be the production of Schneider company, model is NSC250D.The effect of three-phase breaker 500 is major loops of control frequency variator 100, can cut off the power supply of frequency variator 100 when overcurrent fault appears in frequency variator 100 inside with this circuit breaker automatically, also can be used for the power supply of the frequency variator 100 of on-load cut-out just often.The U of frequency variator 100 main circuit output terminals, V, the W terminal is connected with single-pole double throw disconnection switch 600.The model of this single blade double-throw disconnection switch 600 is HS11B-400A/48, and its effect is to be used to provide power frequency or two kinds of different major loop passages of frequency conversion.The mains side of this single-pole double throw disconnection switch 600 has two closing positions, and one of them closing position is the power frequency position, is connected with the 380V ac power supply; Another closing position is the frequency conversion position, and with the U of frequency variator 100 main circuit output terminals, V, the W terminal connects.The load side of single-pole double throw disconnection switch 600 is connected with the main contact of A.C. contactor 1M, 2M in the former start unit 001 of air compressor.The feature of single-pole double throw disconnection switch 600 is that blade of tool and two can not simultaneous closing positions, thereby has stopped the possibility that the main circuit of two kinds of different control modes is connected simultaneously. A.C. contactor 1M, 2M, 1S are the major loop control unit in the former start unit of air compressor master motor, and the utility model is kept, and its objective is the function of master's motor reduced-voltage starting when keeping the power frequency operation mode.If frequency-changing control system breaks down, can be manually switched to the power frequency mode, air compressor is worked under the power frequency condition.
The constant voltage process of this air compressor frequency converting and energy saving device is achieved in that the pressure signal of pressure transducer 200 detections is through pressure regulation instrument 300 adjustings, and relatively form the frequency adjustment signal in the back with pressure given potentiometer 400, the frequency adjustment signal is by the 11# (AI3) of frequency variator 100,12# (COM) terminal is input in the frequency variator 100, frequency variator 100 is according to the power supply of frequency adjustment signal output corresponding frequencies, thereby the rotating speed of the main motor (1MTR) of control air compressor is made corresponding variation with the load number.The frequency variator frequency of okperation raise when the realization delivery pressure was low, and the frequency variator frequency of okperation then reduced when delivery pressure was high.Its working procedure is, when system's gas consumption hour, the outlet pressure of air compressor improves, the resistance of pressure transducer 200 reduces, the power supply of pressure regulation instrument 300 changes the resistance signal of pressure transducer 200 into current signal, its electric current to the input signal of pressure regulation instrument 300 is increased, the increased pressure that pressure regulation instrument 300 shows, simultaneously with the force value that sets by pressure given potentiometer 400 relatively after, to the current signal of frequency variator 100 input inverse change, this signal reduces the corresponding power supply frequency of output after frequency variator 100 inter-process, the corresponding reduction of main motor speed of air compressor, the air compressor air displacement reduces.Air demand and gas consumption balance, frequency variator then maintain the frequency operation of this point.When system's gas consumption was big, course of action was opposite, equally also can obtain wanting the frequency that adapts to load.
In order to realize the variable frequency starting of air compressor frequency converting and energy saving device, the 5# of frequency variator 100 (LI1), 8# (+24V) terminal after 101 series connection of converting operation throw over switch with former start unit in the auxiliary contact 2M-1 that often opens of corner connection tentaculum 2M connect mutually.Described corner connection tentaculum is an electric controling element that is used for main motor star-triangle start system in the original control of air compressor.Its effect is main motor (being that 1M, 1S main contact are connected) behind star-like reduced-voltage starting, through the set time-delay of former intelligent control system, starts corner connection tentaculum 2M, makes main motor total head operation (being that 1M, 2M main contact are connected).Main electric motor starting feature of the present utility model is, when air compressor is chosen in frequency conversion mode state following time, aforesaid start-up course has just been finished the course of action of the control loop of start-up part in original control system, does not cause the substantial startup of main motor.
The start-up course of the main motor under the converting operation mode is: three-phase breaker 500 closes, single-pole double throw disconnection switch 600 is switched to the frequency conversion position, converting operation throw over switch 101 closes, press the initiate key on the former intelligence operation screen of air compressor, main contactor 1M, star contactor 1S adhesive respectively, after time-delay a period of time (length of delay time is by former intelligent control system setting), corner connection tentaculum 2M adhesive, the auxiliary contact 2M-1 of corner connection tentaculum 2M provides the actuating signal of frequency variator, and frequency variator 100 starts.
Can stop VFC frequency conversion cashier's office in a shop during parking earlier and stop throw over switch 102, and then press the parking key on the former intelligence operation screen on the air compressor, to avoid main contactor 1M, the disjunction of corner connection tentaculum 2M on-load.Also can directly press the stop key on the former intelligence operation screen of air compressor, make corner connection tentaculum 2M dead electricity.By the 2M dead electricity, frequency variator 100 is stopped.In addition, frequency variator also has the fault rest button 112 that is connected with frequency variator 100, resetting when being used to break down cashier's office in a shop.
The demonstration of the main signal of this air compressor frequency converting and energy saving device realizes by auxiliary reclay 103,104,9# (R1C) terminal of the coil one termination frequency variator of auxiliary reclay 103, and the other end connects the 220V ac power supply by single-phase circuit breaker 105; 10# (R2A) terminal of the coil one termination frequency variator of auxiliary reclay 104, the other end connects the 220V ac power supply by single-phase circuit breaker 105.After middle relay 103 coils were subjected to electricity, its junction closure, frequency variator frequency conversion trouble signal tutorial light 106 cashier's office in a shop was luminous; After middle relay 104 coils were subjected to electricity, its junction closure, frequency variator converting operation signal lamp 107 cashier's office in a shop was luminous.The operating current of air compressor and voltage are obtained by ammeter 108 and voltmeter 109.The frequency change of frequency variator 100 shows by the frequency display instrument 111 that is connected with frequency variator 100, the 14# terminal of its medium frequency display instrument 111 connects 12# (COM) terminal of frequency variator 100, and the 16# terminal of frequency display instrument 111 connects 15# (AO1) terminal of frequency variator 100.
In addition, be to ensure that the main frame cooling fan in the unit, former intelligent control system can proper functioning under the frequency conversion operating mode, the circuit of the main motor (1MTR) of the circuit of described components and parts or power supply and unit should be separated fully.Described circuit directly is connected on the mains side of three-phase breaker.An A.C. contactor 700 (model is Schneider LC1-D2401M7C) is installed separately, the major loop that is used for main control system cooling fan 002, main frame cooling fan 002 (2MTR) is connected with the 380V ac power supply by this A.C. contactor 700, A.C. contactor 700 control system are provided by the control system of former air compressor, the utility model just changes the primary circuit of main frame cooling fan (2MTR), does not relate to its secondary circuit.Frequency variator 100 is when low-frequency operation, and heat is bigger, in order to give frequency variator 100 coolings, increases a cooling fan 800 again, and this cooling fan 800 links to each other with the 220V ac power supply by single-phase circuit breaker 110.
More than be exactly air compressor frequency converting and energy saving device described in the utility model, by above-mentioned detailed introduction, air compressor energy saving device of the present utility model as can be seen has following advantage:
1, have frequency conversion, two kinds of methods of operation of power frequency, when frequency-changing control system breaks down, can by frequency variator cashier's office in a shop the single-pole double throw disconnection switch switch to the power frequency operation mode rapidly reliably.
2, the double-throw disconnection switch has been stopped the possibility that causes the major loop of power frequency or frequency conversion dual mode to be connected simultaneously because of the control system misoperation.
3, function is controlled in adjusting automatically, and air compressor adopts frequency-changing pressure stabilizing control, and promptly the pressure signal that provides according to the pressure regulation instrument automatic regulating system is regulated the output speed of frequency variator, and the operating mode of load or unload is eliminated in stablizing of holding torque, rotating speed substantially.
4, intactly keep original power frequency star-triangle reduced-voltage starting mode, satisfied the condition of frequency variator soft start simultaneously.
5, selected Schneider frequency variator also makes device have, fast response function, fault reset function and overcurrent, overvoltage, overheated, under-voltage, open-phase protection function.
But, those of ordinary skill in the art will be appreciated that, above embodiment is used for illustrating the utility model, and be not to be used as qualification of the present utility model, as long as in connotation scope of the present utility model, all will drop on claim scope of the present utility model to the above embodiment's variation, modification.
Claims (7)
1. an air compressor frequency converting and energy saving device is characterized in that: comprise frequency variator, pressure transducer, pressure regulation instrument, pressure given potentiometer; The main circuit input end of described frequency variator connects power frequency supply, and the main circuit output terminal connects the former start unit of air compressor; Described pressure given potentiometer is connected on the frequency variator, and described pressure transducer is connected with pressure regulation instrument, and pressure regulation instrument is connected with the pressure given potentiometer with frequency variator respectively again.
2. air compressor frequency converting and energy saving device according to claim 1, it is characterized in that: connect by the single-pole double throw disconnection switch between the main circuit output terminal of described frequency variator and the former start unit of air compressor, two closing positions of described single-pole double throw disconnection switch mains side connect the main circuit output terminal of power frequency supply and frequency variator respectively, and single-pole double throw disconnection switch load side connects the former start unit of air compressor.
3. air compressor frequency converting and energy saving device according to claim 1 and 2 is characterized in that: connect by three-phase breaker between described main circuit of converter input end and the power frequency supply.
4. air compressor frequency converting and energy saving device according to claim 3 is characterized in that: described frequency variator also is connected by the auxiliary contact of often opening of the corner connection tentaculum in the former start unit of converting operation throw over switch and air compressor.
5. air compressor frequency converting and energy saving device according to claim 3 is characterized in that: also include the main frame cooling fan, described main frame cooling fan is connected with power frequency supply by A.C. contactor.
6. air compressor frequency converting and energy saving device according to claim 3 is characterized in that: also include the frequency variator cooling fan, described this frequency variator cooling fan is connected with the 220V power supply by single-phase circuit breaker.
7. air compressor frequency converting and energy saving device according to claim 3, it is characterized in that: described frequency variator also is connected with two auxiliary reclays and frequency conversion trouble signal tutorial light and converting operation signal lamp, and described two auxiliary reclays are connected with power supply by single-phase circuit breaker.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU200720074646XU CN201083194Y (en) | 2007-09-13 | 2007-09-13 | Air compressor frequency conversion energy-saving device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU200720074646XU CN201083194Y (en) | 2007-09-13 | 2007-09-13 | Air compressor frequency conversion energy-saving device |
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| CN201083194Y true CN201083194Y (en) | 2008-07-09 |
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| CNU200720074646XU Expired - Fee Related CN201083194Y (en) | 2007-09-13 | 2007-09-13 | Air compressor frequency conversion energy-saving device |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102220961A (en) * | 2010-04-19 | 2011-10-19 | 深圳市汇川技术股份有限公司 | Air compressor energy-saving and pressure-stabilizing controlling system and air compressor |
| CN101901014B (en) * | 2009-05-27 | 2012-02-22 | 宝山钢铁股份有限公司 | Method for controlling forecast pressure regulation in air compression stations |
| CN102364108A (en) * | 2011-05-12 | 2012-02-29 | 上海英格索兰压缩机有限公司 | Frequency conversion type screw air compressor electric cabinet |
| CN102436773A (en) * | 2011-09-15 | 2012-05-02 | 宁波市鄞州供电局 | Analog circuit breaker |
| CN101725515B (en) * | 2009-11-12 | 2013-08-07 | 厦门市万树科技有限公司 | Air compressor energy-saving control method |
| CN103334913A (en) * | 2013-07-25 | 2013-10-02 | 河南省通信电缆有限公司 | Control system of air compressor |
| CN105782047A (en) * | 2015-12-30 | 2016-07-20 | 无锡市迪卡瑞控制技术有限公司 | Controller and control method for fuzzy control over screw air compressor |
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2007
- 2007-09-13 CN CNU200720074646XU patent/CN201083194Y/en not_active Expired - Fee Related
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101901014B (en) * | 2009-05-27 | 2012-02-22 | 宝山钢铁股份有限公司 | Method for controlling forecast pressure regulation in air compression stations |
| CN101725515B (en) * | 2009-11-12 | 2013-08-07 | 厦门市万树科技有限公司 | Air compressor energy-saving control method |
| CN102220961A (en) * | 2010-04-19 | 2011-10-19 | 深圳市汇川技术股份有限公司 | Air compressor energy-saving and pressure-stabilizing controlling system and air compressor |
| CN102364108A (en) * | 2011-05-12 | 2012-02-29 | 上海英格索兰压缩机有限公司 | Frequency conversion type screw air compressor electric cabinet |
| CN102436773A (en) * | 2011-09-15 | 2012-05-02 | 宁波市鄞州供电局 | Analog circuit breaker |
| CN102436773B (en) * | 2011-09-15 | 2014-03-12 | 宁波市鄞州供电局 | Analog circuit breaker |
| CN103334913A (en) * | 2013-07-25 | 2013-10-02 | 河南省通信电缆有限公司 | Control system of air compressor |
| CN103334913B (en) * | 2013-07-25 | 2016-05-18 | 河南省通信电缆有限公司 | A kind of control system of air compressor |
| CN105782047A (en) * | 2015-12-30 | 2016-07-20 | 无锡市迪卡瑞控制技术有限公司 | Controller and control method for fuzzy control over screw air compressor |
| CN105782047B (en) * | 2015-12-30 | 2019-02-12 | 无锡市艾克特电气股份有限公司 | A kind of controller and control method of blurring control screw air compressor |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20080709 Termination date: 20140913 |
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| EXPY | Termination of patent right or utility model |