CN103671055B - The intelligence control system of piston reciprocating type air-compressor set and control method - Google Patents
The intelligence control system of piston reciprocating type air-compressor set and control method Download PDFInfo
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- CN103671055B CN103671055B CN201310683675.6A CN201310683675A CN103671055B CN 103671055 B CN103671055 B CN 103671055B CN 201310683675 A CN201310683675 A CN 201310683675A CN 103671055 B CN103671055 B CN 103671055B
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Abstract
The invention discloses the intelligence control system of a kind of piston reciprocating type air-compressor set and control method, wherein control system to include: central controller and all connected frequency conversion control unit and on off control unit, frequency conversion control unit is connected with the multiple stage frequency conversion air compressor of air-compressor set, and on off control unit is connected with other non-frequency air compressor machines in air-compressor set;This intelligence control system also includes the temperature transmitter and the pressure transmitter that are connected with central controller, and temperature transmitter is all connected with all air compressor machines in air-compressor set, and pressure transmitter is connected with air accumulator, and air accumulator is connected with all air compressor machines in air-compressor set.The present invention controls operation and the stopping of frequency conversion air compressor and other non-frequency air compressor machine by frequency conversion control unit and on off control unit, air-compressor set to be carried out the adjustment of associating tolerance, large-scale step-less adjustment can be carried out according to the actual air consumption consuming gas equipment under user's difference operating mode, significantly reduce energy consumption.
Description
Technical field
The present invention relates to the Based Intelligent Control of piston reciprocating type air-compressor set, particularly relate to intelligence control system and the control method of a kind of piston reciprocating type air-compressor set.
Background technology
During the work of piston reciprocating type air-compressor set; the air demand consuming gas equipment in production procedure often has bigger fluctuation; when the capacity of equipment air consumption Yu air-compressor set is incompatible; just need air-compressor set is carried out tolerance adjustment; so that the capacity of air-compressor set adapts to the requirement of air consumption change, keep the pressure stability in pipe network.Therefore, the air-compressor set of production scene configuration is designed with changing the air volume regulating device of air-compressor set capacity.
At present, piston reciprocating type air-compressor set realizes rough tolerance adjustment often through the mode of start-stop air compressor machine, opens air-compressor set according to currently maximum air demand and supplies, unnecessary gas emptying.Although this control method is simple and reliable, but the air compressor machine opened is in all the time and operates at full capacity, and therefore consumes energy huge.Simultaneously, it is necessary to manual intervention, automaticity is low.
In prior art, have, by monitoring module, the pressure in air-compressor set output to pipeline is monitored detection, and after the data monitored are processed by middle control module send instruction air-compressor set is adjusted control, but its tolerance range of accommodation is very limited, there is blind spot in control process, it is impossible to meets the requirement that tolerance regulates under all working conditions.
Summary of the invention
The technical problem to be solved in the present invention is in that for tolerance range of accommodation in prior art very limited, there is the defect of blind spot in control process, there is provided a kind of and can carry out large-scale step-less adjustment according to the actual air consumption consuming gas equipment under user's difference operating mode, and the intelligent control method of the piston reciprocating type air-compressor set of energy consumption can be significantly reduced.
The technical solution adopted for the present invention to solve the technical problems is:
The intelligence control system of a kind of piston reciprocating type air-compressor set is provided, including: central controller and all connected frequency conversion control unit and on off control unit, described frequency conversion control unit is connected with the multiple stage frequency conversion air compressor of air-compressor set, and described on off control unit is connected with other non-frequency air compressor machines in air-compressor set;
This intelligence control system also includes the temperature transmitter and the pressure transmitter that are connected with described central controller, described temperature transmitter is all connected with all air compressor machines in air-compressor set, described pressure transmitter is connected with air accumulator, and described air accumulator is connected with all air compressor machines in air-compressor set.
In control system of the present invention, described central control unit includes data storage cell and data processing unit, described data storage cell is connected with described temperature transmitter and described pressure transmitter, and described data processing unit is connected with described frequency conversion control unit and described on off control unit.
In control system of the present invention, this control system also includes display, is connected with described data processing unit.
In control system of the present invention, this control system also includes alarm, is connected with described central controller.
In control system of the present invention, described frequency conversion control unit is connected with at least three frequency conversion air compressors of air-compressor set.
The present invention also provides for the intelligent control method of a kind of piston reciprocating type air-compressor set, comprises the following steps:
When equipment is properly functioning, by pressure transmitter, the pressure in air accumulator is monitored, and pressure information is sent to central controller;
When the gas pressure in air accumulator is constant or fluctuates in default little scope, central controller is failure to actuate, and system keeps current state to run;
When pressure continues to change in Preset Time, according to pressure information, central controller judges that pressure changes whether within the scope of variable frequency adjustment, if within the scope of variable frequency adjustment, central controller sends instructions to frequency conversion control unit, frequency conversion air compressor in air-compressor set is carried out VFC, regulate its working speed and then regulate its capacity, until gas pressure reaches setting value in air accumulator;
If reservoir pressure situation of change is beyond variable frequency adjustment scope, then central controller sends control instruction on off control unit, control to open or stop the frequency conversion air compressor in air-compressor set or other non-frequency air compressor machines by off control unit, and send control instruction to frequency conversion control unit, regulated the capacity of frequency conversion air compressor by frequency conversion control unit, the capacity making air-compressor set total reaches poised state with user's air consumption.
In control method of the present invention, described on off control unit adopts the mode of soft start to control the non-frequency air compressor machine in air-compressor set.
In control method of the present invention, the pressure transmitter of acquisition and the detection data of temperature transmitter are shown over the display by described central controller after treatment.
In control method of the present invention, when abnormal state occurs in system operation, described central controller sends alarm signal to alarm.
The beneficial effect comprise that: the multiple air compressors in piston reciprocating type air-compressor set is carried out VFC by the present invention, rather than all of air compressor machine all carries out VFC, and improvement cost is not high.Unlatching and the stopping of frequency conversion air compressor and other non-frequency air compressor machine is controlled by off control module, air-compressor set to be carried out the adjustment of associating tolerance, the present invention can carry out large-scale step-less adjustment according to the actual air consumption consuming gas equipment under user's difference operating mode, can significantly reduce energy consumption.Additionally the present invention adopts Based Intelligent Control, and automaticity is high, greatly reduces artificial dependency degree, also makes stability that system runs and reliability be greatly improved simultaneously.
Accompanying drawing explanation
Below in conjunction with drawings and Examples, the invention will be further described, in accompanying drawing:
Fig. 1 is the structural representation of the intelligence control system of embodiment of the present invention piston reciprocating type air-compressor set;
Fig. 2 is the flow chart of the intelligent control method of embodiment of the present invention piston reciprocating type air-compressor set.
Detailed description of the invention
In order to make the purpose of the present invention, technical scheme and advantage clearly understand, below in conjunction with drawings and Examples, the present invention is further elaborated.Should be appreciated that specific embodiment described herein is only in order to explain the present invention, is not intended to limit the present invention.
As it is shown in figure 1, the intelligence control system of embodiment of the present invention piston reciprocating type air-compressor set includes: central controller and all connected frequency conversion control unit and on off control unit, frequency conversion control unit is connected with the multiple stage frequency conversion air compressor of air-compressor set.The present invention receives pressure transmitter by central controller and the data signal of coming is transmitted in temperature sensor, process by analysis, frequency conversion control unit and on off control unit are controlled, adjust the running status of frequency conversion air compressor and other non-frequency air compressor machines, the tolerance realizing air-compressor set regulates, and meets the demand of user's air consumption change.
In one embodiment of the invention three air compressor machines in air-compressor set are carried out Frequency Conversion Modification, become frequency conversion air compressor by common air compressor retrofit, it is possible to be controlled by frequency variation signal.On off control unit is connected with other non-frequency air compressor machines (namely without the common air compressor machine of Frequency Conversion Modification) in air-compressor set.Run through air compressor machine and other expense frequency conversion air compressor do not transformed of Frequency Conversion Modification by controlling multiple stage, to meet the demand of user's air consumption change simultaneously.
This intelligence control system also includes the temperature transmitter and the pressure transmitter that are connected with central controller, and temperature transmitter is all connected with all air compressor machines in air-compressor set, and pressure transmitter is connected with air accumulator, and air accumulator is connected with all air compressor machines in air-compressor set.In piston reciprocating type air-compressor set running, central controller, by the gas pressure change in pressure transmitter monitoring air accumulator, utilizes the axle temperature of the compressor in temperature transmitter monitoring air compressor machine and motor.
In one embodiment of the present of invention, central control unit includes data storage cell and data processing unit, and data storage cell is connected with temperature transmitter and pressure transmitter, and data processing unit is connected with frequency conversion control unit and on off control unit.When user's air consumption changes, if the capacity of air-compressor set remains in that constant, causing tolerance unbalanced supply-demand, in air accumulator, gas pressure can produce change.Now, the pressure changing monitored is passed to the data storage cell of central controller by pressure transmitter as electronic signals that be connected with air accumulator, by the data processing unit of central controller, data are processed again, and the control instruction of generation is sent to frequency conversion control unit and on off control unit, by the two functional unit, compressor bank is controlled, making air-compressor set air demand automatically adapt to user and consume the air demand of gas equipment, in maintenance air accumulator, gas pressure stablizes.
This control system also includes display, is connected with data processing unit.Data processing unit generates system state data after the detection data of temperature transmitter and pressure transmitter are processed, and is shown by display.
In one embodiment of the present of invention, this control system also includes alarm, is connected with central controller.When system state data is beyond set point, central controller sends alarm signal to alarm.
The intelligent control method of embodiment of the present invention piston reciprocating type air-compressor set, as in figure 2 it is shown, comprise the following steps:
When equipment is properly functioning, by pressure transmitter, the pressure in air accumulator is monitored, and pressure information is sent to central controller;
When the gas pressure in air accumulator is constant or fluctuates in default little scope, central controller is failure to actuate, and system keeps current state to run;
When pressure continues to change in Preset Time, according to pressure information, central controller judges that pressure changes whether within the scope of variable frequency adjustment, if within the scope of variable frequency adjustment, central controller sends instructions to frequency conversion control unit, frequency conversion air compressor in air-compressor set is carried out VFC, regulate its working speed and then regulate its capacity, until gas pressure reaches setting value in air accumulator;
If reservoir pressure situation of change is beyond variable frequency adjustment scope, then central controller sends control instruction on off control unit, control to open or stop the frequency conversion air compressor in air-compressor set or other non-frequency air compressor machines by off control unit, and send control instruction to frequency conversion control unit, regulated the capacity of frequency conversion air compressor by frequency conversion control unit, the capacity making air-compressor set total reaches poised state with user's air consumption.As in figure 2 it is shown, in one embodiment of the present of invention, if reservoir pressure situation of change is beyond variable frequency adjustment scope, be specially when force value is lower than the lower limit of frequency conversion adjustable extent, close a frequency conversion or common (i.e. non-frequency) compressor;When force value is not less than the lower limit of frequency conversion adjustable extent, open a frequency conversion or common (i.e. non-frequency) compressor, until pressure reaches setting.
On off control unit adopts the mode of soft start to control the non-frequency piston reciprocating type air compressor machine in air-compressor set.
The pressure transmitter of acquisition and the detection data of temperature transmitter are shown over the display by central controller after treatment.
When abnormal state occurs in system operation, central controller sends alarm signal to alarm.
In one particular embodiment of the present invention, certain enterprise utilizes above-mentioned control system that piston reciprocating type air-compressor set is carried out Based Intelligent Control.The piston reciprocating type air compressor machine structure air-compressor set that certain enterprise uses 10 power to be 132KW, opens seven for three during normal operation.In seven properly functioning air compressor machines three can be carried out Frequency Conversion Modification by the present invention, and the gamut being realized air-compressor set capacity by intelligent control method is regulated.
Following table one realizes the operation control strategy of air-compressor set when each operating mode capacity regulates for air-compressor set.If the capacity at full capacity of separate unit air compressor machine is set to unit 1, then the maximum air consumption of this enterprise is 7, when actual air consumption changes in 5.8 ~ 7 scopes, takes the scheme simultaneously run with the logical air compressor machine of 4 Daeporis and three frequency conversion air compressors to carry out actual production.When actual air consumption is lower than 5.8, it is necessary to turn off a number of common air compressor machine or frequency conversion air compressor.If actual air consumption is 6.5, the logical air compressor machine full load of 4 Daeporis runs the tolerance providing 4 units, remain 2.5 tolerance to supply with three frequency conversion air compressors, then the average tolerance of every supply is 2.5/3=0.833, central controller controls frequency conversion control unit after data process, three electric machine frequencies being adjusted to the 83.3% of rated frequency respectively, makes air demand and air consumption balance each other, system pressure keeps constant.
Table one: air-compressor set runs control strategy
Operation control strategy according to table one, if actual air consumption is 5.5, intelligence control system automatically turns off a frequency conversion air compressor by off control unit or the logical air compressor machine of a Daepori regulates capacity.The logical air compressor machine of the first scheme 4 Daepori and 2 frequency conversion air compressors run simultaneously, range of accommodation is 5.2 ~ 6.0, common air compressor machine full load runs the tolerance providing 4 units, and the tolerance of 1.5 units of residue is supplied by two frequency conversion air compressors, then every quantity delivered is 1.5/2=0.75;Three common compressor of first scheme and three frequency-changeable compressors run simultaneously, and range of accommodation is 4.8 ~ 6, then the air demand of every frequency-changeable compressor is (5.5-3)/3=0.833.Intelligence control system adopts fuzzy control method to automatically select one of which scheme according to air-compressor set ruuning situation and is adjusted.
To sum up, the present invention is by transforming the part air compressor machine in piston reciprocating type air-compressor set, rather than air compressor machine all of in piston reciprocating type air-compressor set is all carried out Frequency Conversion Modification, and improvement cost is low.Carry out associating tolerance by the air compressor machine of start and stop Frequency Conversion Modification and other air compressor machine to regulate, it is possible to the actual air consumption according to consuming gas equipment under user's difference operating mode carries out large-scale step-less adjustment, significantly reduces energy consumption.The present invention adopts Based Intelligent Control, and automaticity is high, greatly reduces artificial dependency degree, also makes stability that system runs and reliability be greatly improved simultaneously.
It should be appreciated that for those of ordinary skills, it is possible to improved according to the above description or converted, and all these are improved and convert the protection domain that all should belong to claims of the present invention.
Claims (9)
1. the intelligence control system of a piston reciprocating type air-compressor set, it is characterized in that, including: central controller and all connected frequency conversion control unit and on off control unit, described frequency conversion control unit is connected with the multiple stage frequency conversion air compressor of air-compressor set, and described on off control unit is connected with other non-frequency air compressor machines in air-compressor set;
This intelligence control system also includes the temperature transmitter and the pressure transmitter that are connected with described central controller, described temperature transmitter is all connected with all air compressor machines in air-compressor set, described pressure transmitter is connected with air accumulator, and described air accumulator is connected with all air compressor machines in air-compressor set;Central controller receives pressure transmitter and temperature transmitter transmits the data signal of coming, and processes by analysis, frequency conversion control unit and on off control unit are controlled;
If reservoir pressure situation of change is beyond variable frequency adjustment scope, then central controller sends control instruction on off control unit, control to open or stop the frequency conversion air compressor in air-compressor set or other non-frequency air compressor machines by off control unit, and send control instruction to frequency conversion control unit, regulated the capacity of frequency conversion air compressor by frequency conversion control unit, the capacity making air-compressor set total reaches poised state with user's air consumption.
2. control system according to claim 1, it is characterized in that, described central control unit includes data storage cell and data processing unit, described data storage cell is connected with described temperature transmitter and described pressure transmitter, and described data processing unit is connected with described frequency conversion control unit and described on off control unit.
3. control system according to claim 2, it is characterised in that this control system also includes display, is connected with described data processing unit.
4. control system according to claim 1, it is characterised in that this control system also includes alarm, is connected with described central controller.
5. control system according to claim 1, it is characterised in that described frequency conversion control unit is connected with at least three frequency conversion air compressors of air-compressor set.
6. the intelligent control method of a piston reciprocating type air-compressor set, it is characterised in that comprise the following steps:
When equipment is properly functioning, by pressure transmitter, the pressure in air accumulator is monitored, and pressure information is sent to central controller;
When the gas pressure in air accumulator is constant or fluctuates in default little scope, central controller is failure to actuate, and system keeps current state to run;
Central controller receives pressure transmitter and temperature transmitter transmits the data signal of coming, and processes by analysis, frequency conversion control unit and on off control unit are controlled;When pressure continues to change in Preset Time, according to pressure information, central controller judges that pressure changes whether within the scope of variable frequency adjustment, if within the scope of variable frequency adjustment, central controller sends instructions to frequency conversion control unit, frequency conversion air compressor in air-compressor set is carried out VFC, regulate its working speed and then regulate its capacity, until gas pressure reaches setting value in air accumulator;
If reservoir pressure situation of change is beyond variable frequency adjustment scope, then central controller sends control instruction on off control unit, control to open or stop the frequency conversion air compressor in air-compressor set or other non-frequency air compressor machines by off control unit, and send control instruction to frequency conversion control unit, regulated the capacity of frequency conversion air compressor by frequency conversion control unit, the capacity making air-compressor set total reaches poised state with user's air consumption.
7. control method according to claim 6, it is characterised in that described on off control unit adopts the mode of soft start to control the unlatching of non-frequency air compressor machine in air-compressor set.
8. control method according to claim 6, it is characterised in that the pressure transmitter of acquisition and the detection data of temperature transmitter are shown over the display by described central controller after treatment.
9. control method according to claim 6, it is characterised in that when abnormal state occurs in system operation, described central controller sends alarm signal to alarm.
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