KR101744578B1 - Method and system of controlling multi air compressor - Google Patents
Method and system of controlling multi air compressor Download PDFInfo
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- KR101744578B1 KR101744578B1 KR1020150073763A KR20150073763A KR101744578B1 KR 101744578 B1 KR101744578 B1 KR 101744578B1 KR 1020150073763 A KR1020150073763 A KR 1020150073763A KR 20150073763 A KR20150073763 A KR 20150073763A KR 101744578 B1 KR101744578 B1 KR 101744578B1
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- pressure
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- air compressor
- virtual
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
- F04B49/007—Installations or systems with two or more pumps or pump cylinders, wherein the flow-path through the stages can be changed, e.g. from series to parallel
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C28/00—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Control Of Positive-Displacement Pumps (AREA)
Abstract
A multi-air compressor control method and system capable of effectively controlling the operating conditions of a multi-air compressor. A method of controlling operation of a multiple air compressor system in which a plurality of air compressors are connected in parallel comprises the steps of: measuring a target pressure of compressed air at a specific location by an air compressor; Comparing the measured target pressure measurement value with a preset target pressure setting value; Calculating an imaginary virtual pressure value that is different from or different from an individual discharge pressure value of the air compressor according to a result of comparison between the target pressure measurement value and the target pressure setting value; And controlling the individual operating conditions of the air compressor on the basis of the virtual pressure value, wherein the air compressor includes independent controls for independently controlling operating conditions, The individual operating conditions are controlled.
Description
The present invention relates to a multi-air compressor control method and system, and more particularly, to a multi-air compressor control method and system capable of effectively controlling the operating conditions of a plurality of air compressors.
When a plurality of air compressors are connected in parallel in an industrial field in various fields, in order to supply a constant pressure without waste of energy, it is necessary to maintain uniform pressure through load control of a plurality of air compressors.
As one of the methods for maintaining the target pressure by the plurality of air compressors at a uniform set value, it is necessary to provide a separate control panel for each air compressor, , The intake valve of each air compressor is opened and closed to regulate the total amount of compressed air to adjust the target pressure.
A control system of a conventional multi-air compressor using a plurality of air compressors connected to each other uses an integrated controller for uniformly controlling each air compressor to maintain a target pressure, and controls the discharge pressure of each air compressor through an integrated controller can do.
However, in many cases, when a plurality of air compressors are connected and used, different types or manufacturers' air compressors are used in many cases. Since the control panels are different according to the types and manufacturers of the respective air compressors, It is inevitably required to replace the control panel installed in each air compressor with the same model.
That is, even if each of the air compressors connected to each other is uniformly controlled through the integrated control unit, if the control panel of each air compressor is different depending on the type and manufacturer, it is difficult to uniformly control the air compressors by the integrated control unit. There is a problem that the control panel of each air compressor needs to be replaced with a control panel of the same model. Furthermore, since the control panel of each air compressor is very expensive, there is a problem that the cost of replacing the control panel increases as the number of connections of different air compressors increases.
On the other hand, conventionally, the control panel is not replaced, the discharge valve is installed in the discharge pipe of each air compressor, and the integrated control unit opens and closes the discharge valve, so that the target pressure by a plurality of air compressors can be maintained at a uniform set value A technique has been disclosed.
However, in the conventional method of opening and closing the discharge valve of each air compressor and maintaining the set value of the target pressure, there is a problem in that there is a risk factor according to the valve control.
That is, in the case of the conventional control system using the discharge valve, a surge occurs during excessive control of the discharge valve, causing vibration, and the air compressor may be stopped. In addition, there is a problem that a change in the discharge pressure due to the operation of the discharge valve is very sensitive, resulting in an uncontrollable state.
Further, in order to continuously control using the discharge valve, a constant differential pressure is always applied to the discharge valve, so there is a problem that energy loss is caused by the valve differential pressure and operating efficiency is lowered.
In recent years, a variety of studies have been made on an air compressor control method capable of performing stable and efficient integrated control, simplifying the structure and reducing the cost, but the development of the air compressor control method is insufficient have.
The present invention provides a multi-air compressor control method and system capable of effectively controlling the operating conditions of a plurality of air compressors.
In particular, according to the present invention, it is possible to perform integrated control of a multi-air compressor without replacing a control panel or installing a separate valve by using a virtual pressure signal value, To provide a multi-air compressor control method and system.
In addition, the present invention provides a multi-air compressor control method and system capable of maximizing energy savings as well as having a wide control range and a high response speed.
The present invention also provides a multi-air compressor control method and system that can simplify the structure and reduce cost.
The present invention also provides a multi-air compressor control method and system that can improve compatibility of different types and manufacturers of air compressors.
According to a preferred embodiment of the present invention, there is provided a method of controlling operation of a multi-air compressor system in which a plurality of air compressors are connected in parallel, comprising the steps of: Measuring a target pressure; Comparing the measured target pressure measurement value with a preset target pressure setting value; Calculating an imaginary virtual pressure value that is different from or different from an individual discharge pressure value of the air compressor according to a result of comparison between the target pressure measurement value and the target pressure setting value; And controlling the individual operating conditions of the air compressor on the basis of the virtual pressure value, wherein the air compressor includes independent controls for independently controlling operating conditions, The individual operating conditions are controlled.
The present invention controls the operation of the air compressor by simply manipulating the pressure signal transmitted to the individual control unit with a virtual pressure signal without having to replace the control panel or attach the valve in order to perform integrated control of the multi air compressor .
For reference, it is possible to judge whether or not the integrated value of the current value and the pressure value of the air compressor has been set in the preset state. If the integrated control of the air compressor is determined, It is possible to measure the target pressure in the main piping to which the piping is joined.
The virtual pressure value can be calculated by calculating the pressure increase / decrease value by comparing the target pressure measurement value with the target pressure setting value, and by adding / subtracting the pressure increase / decrease value to the pressure signal value (individual discharge pressure value).
The virtual pressure value can be calculated in various ways depending on the result of comparison between the target pressure measurement value and the target pressure setting value. For example, when the target pressure measurement value is higher than the target pressure setting value as a result of comparing the target pressure measurement value and the target pressure setting value, the virtual pressure value input to the individual control unit may be calculated to be higher than the individual discharge pressure value . As another example, when the target pressure measurement value is lower than the target pressure setting value as a result of comparing the target pressure measurement value and the target pressure setting value, the virtual pressure value input to the individual control section may be calculated to be lower than the individual discharge pressure value have. On the other hand, when the target pressure measurement value is equal to the target pressure setting value as a result of comparing the target pressure measurement value and the target pressure setting value, the virtual pressure value can be calculated to be equal to the individual discharge pressure value.
On the other hand, if the target pressure measurement value is lower than the target pressure setting value, a step of comparing the current measurement value measuring the current supplied to the air compressor with a preset current setting value may be added, Can be calculated according to the result of comparison between the value and the current set value. For example, when the current measurement value is higher than the current setting value, the virtual pressure value input to the individual control section can be calculated to be higher than the individual discharge pressure value. In another example, when the current measurement value is lower than the current setting value, the virtual pressure value input to the individual control section can be calculated to be lower than the individual discharge pressure value.
The individual control unit can control the individual operating conditions of the air compressor based on the virtual pressure value. For example, when the target pressure measurement value is higher than the target pressure setting value, the virtual pressure value can be calculated to be higher than the individual discharge pressure value, and when a virtual pressure value higher than the individual discharge pressure value is transmitted to the individual control unit, It is determined that the current state is a high load state and the discharge pressure of the air compressor can be lowered. In contrast, when the target pressure measurement value is lower than the target pressure setting value, the virtual pressure value can be calculated to be lower than the individual discharge pressure value, and when a virtual pressure value lower than the individual discharge pressure value is transmitted to the individual control unit, The controller may determine that the current state of the load is low and increase the discharge pressure of the air compressor.
The manner in which the individual control unit controls the individual operating conditions of the air compressor based on the virtual pressure value can be appropriately changed according to the required conditions and design specifications. For example, controlling the individual operating conditions of the air compressor based on the virtual pressure value may include: inputting a virtual pressure value to the individual controller; Comparing the hypothetical pressure value with an individual pressure preset value preset in the individual control unit; And controlling an inlet guide vane (IGV) that adjusts an individual suction capacity of the air compressor according to a result of comparison between the virtual pressure value and the individual pressure set value. For example, when the virtual pressure value is higher than the individual pressure set value, the individual control may control the inlet guide vane to reduce the individual discharge pressure of the air compressor. In another example, when the virtual pressure value is lower than the individual pressure set value, the individual control may control the inlet guide vane to increase the individual discharge pressure of the air compressor.
According to another preferred embodiment of the present invention, a multiple air compressor system in which a plurality of air compressors are connected, each of which is provided with a separate control unit for independently controlling the operating conditions, calculates a target pressure of the compressed air at a specific position by the air compressor A target pressure sensor to measure; An integrated controller for integrally controlling the individual control units and calculating the pressure increase / decrease value according to a result of comparing the target pressure measurement value measured by the target pressure sensor with a predetermined target pressure setting value; And a pressure signal controller for transmitting a virtual pressure value added or subtracted in accordance with the pressure increase / decrease value calculated by the integrated controller to the individual controller, wherein the integrated controller controls the air compressor .
According to the multi-air compressor control method and system of the present invention, it is possible to effectively control the integrated operating conditions of the multi-air compressor without waste of energy.
Particularly, according to the present invention, it is possible to control the individual operating conditions of the air compressor by using virtual virtual pressure values which are added or subtracted from the actual individual discharge pressure values of the air compressor, So that the integrated control of the multi-air compressor can be performed more effectively regardless of the maker.
As described above, conventionally, in order to perform integrated control of the multi-air compressor, the control panel must be replaced or the valve must be installed for each air compressor. Particularly, in the case of using the valve, there is a problem in that many risk factors are accompanied by the valve control.
However, according to the present invention, since the operation of the air compressor can be controlled by simply manipulating the pressure signal transmitted to the individual control unit with the virtual pressure signal without having to replace the control panel or attach the valve, Installation time can be reduced.
Furthermore, according to the present invention, since the operation of the air compressor can be controlled by the electrical control for virtually operating the pressure signal, the response speed is high and the control range can be further expanded.
Further, according to the present invention, not only a uniform target pressure control is possible, but also energy saving efficiency can be maximized.
In addition, according to the present invention, it is possible to improve the compatibility of different types and manufacturers of air compressors, and to reduce maintenance and repair costs.
1 and 2 are views for explaining a multi-air compressor control system according to the present invention.
FIG. 3 is a diagram for explaining the relationship between the integrated controller and the pressure signal controller in the multi-air compressor control system according to the present invention.
4 is a view for explaining a method of controlling a multi-air compressor according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments. For reference, the same numbers in this description refer to substantially the same elements and can be described with reference to the contents described in the other drawings under the above-mentioned rules, and the contents which are judged to be obvious to the person skilled in the art or repeated can be omitted.
1 and 2 are views for explaining a multi-air compressor control system according to the present invention. FIG. 3 is a diagram for explaining a relationship between an integrated controller and a pressure signal controller, which is a multi air compressor control system according to the present invention .
As shown in these drawings, the multi-air compressor control system according to the present invention includes an
The plurality of
An
The
The
As the inlet guide vane, a usual inlet guide vane usable in a
In addition, a passive control panel may be used as the
Particularly, as the control panel constituting the
The
As the
The
For example, when the target pressure measured by the
In addition, the target pressure set value may be set in advance according to the number and configuration of the
The
For example, in the present invention, the pressure
As the
More specifically, the
In this way, the
The virtual pressure value by the
In the above-described embodiment of the present invention, the pressure signal control unit is configured to convert the pressure signal into a state of being added or subtracted and output. However, in some cases, Or the like.
If the target pressure measurement value is lower than the target pressure setting value, a step of comparing the current measurement value, which measures the current supplied to the
Hereinafter, a method of controlling a multi-air compressor according to the present invention will be described with reference to FIG.
4 is a view for explaining a method of controlling a multi-air compressor according to the present invention. In addition, the same or equivalent portions as those in the above-described configuration are denoted by the same or equivalent reference numerals, and a detailed description thereof will be omitted.
Referring to FIG. 4, a method for controlling a multi-air compressor according to the present invention includes: measuring a target pressure of compressed air at a specific position by an
First, a current value applied to the
Next, when the integrated control participation of the
Then, the measured target pressure measurement value is compared with the target pressure set value previously set in the
Next, a hypothetical virtual pressure value which is added or subtracted from the individual discharge pressure value of the
As described above, the virtual pressure value is calculated by comparing the target pressure measurement value with the target pressure measurement value in the
The virtual pressure value may be calculated in various manners according to the result of comparison between the target pressure measurement value and the target pressure setting value.
For example, when the target pressure measurement value is higher than the target pressure setting value as a result of comparing the target pressure measurement value with the target pressure setting value, The virtual pressure value input to the
Meanwhile, as described above, when the target pressure measurement value is lower than the target pressure setting value, a step of comparing the current measurement value measured with the current supplied to the
The virtual pressure value according to the current value comparison result can be calculated in various ways according to the required conditions. For example, when the current measurement value is higher than the current setting value, the virtual pressure value input to the
Next, the individual operating conditions of the
A virtual virtual pressure value reflecting the pressure increase / decrease value calculated by the
For example, when the target pressure measurement value is higher than the target pressure setting value, the virtual pressure value may be calculated to be higher than the individual discharge pressure value, and a virtual pressure value higher than the individual discharge pressure value may be transmitted to the
On the contrary, when the target pressure measurement value is lower than the target pressure setting value, the virtual pressure value can be calculated to be lower than the individual discharge pressure value, and the virtual pressure value lower than the individual discharge pressure value is transmitted to the
The manner in which the
Hereinafter, the step of controlling the individual operation conditions of the
For example, when the virtual pressure value is higher than the individual pressure set value, the
Meanwhile, when the target pressure set value and the target pressure measurement value become equal to each other, the
Also, when unloading or stopping the facility, the
Also, when the actual pressure of the equipment rises to the upper limit pressure set value level, the
Although the present invention has been described with reference to the preferred embodiments thereof, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention as defined in the following claims. It can be understood that
10: air compressor 12: individual pressure sensor
100: Individual control unit 200: Target pressure sensor
300: Integrated controller 400: Pressure signal controller
Claims (18)
Measuring a target pressure of compressed air at a specific position by the air compressor;
Comparing the measured target pressure measurement value with a predetermined target pressure setting value;
Calculating an imaginary virtual pressure value that is different from or different from an individual discharge pressure value of the air compressor according to a comparison result between the target pressure measurement value and the target pressure setting value; And
And controlling the individual operating conditions of the air compressor based on the virtual pressure value,
Wherein the air compressor includes an independent control unit that independently controls operation conditions, and the individual control unit controls individual operation conditions of the air compressor based on the virtual pressure value.
Wherein the step of controlling the individual operating conditions of the air compressor based on the virtual pressure value comprises:
Inputting the virtual pressure value to the individual control unit;
Comparing the virtual pressure value and a predetermined individual pressure setting value; And
Controlling an inlet guide vane (IGV) for adjusting an individual suction capacity of the air compressor according to a result of comparison between the virtual pressure value and the individual pressure setting value;
Wherein the control unit is operable to control the air compressor.
Wherein when the virtual pressure value is higher than the individual pressure set value, the individual discharge pressure of the air compressor is reduced by the inlet guide vane.
Wherein the inlet pressure of the air compressor is increased by the inlet guide vane if the virtual pressure value is lower than the individual pressure set value.
Calculating a virtual virtual pressure value which is added or subtracted from the individual discharge pressure value of the air compressor according to the comparison result of the target pressure measurement value and the target pressure setting value,
Wherein when the target pressure measurement value is higher than the target pressure setting value, the virtual pressure value input to the individual control unit is calculated to be higher than the individual discharge pressure value.
Calculating a virtual virtual pressure value which is added or subtracted from the individual discharge pressure value of the air compressor according to the comparison result of the target pressure measurement value and the target pressure setting value,
Wherein when the target pressure measurement value is lower than the target pressure setting value, the virtual pressure value input to the individual control unit is calculated to be lower than the individual discharge pressure value.
And comparing the measured current value with the predetermined current setting value when the target pressure measurement value is lower than the target pressure setting value,
Wherein the virtual pressure value is calculated according to a result of comparison between the current measurement value and the current setting value.
Wherein when the current measurement value is higher than the current setting value, the virtual pressure value input to the individual control unit is calculated to be higher than the individual discharge pressure value.
Wherein when the current measurement value is lower than the current setting value, the virtual pressure value input to the individual control unit is calculated to be lower than the individual discharge pressure value.
Calculating a virtual virtual pressure value which is added or subtracted from the individual discharge pressure value of the air compressor according to the comparison result of the target pressure measurement value and the target pressure setting value,
Wherein when the target pressure measurement value is equal to the target pressure setting value, the virtual pressure value input to the individual control unit is calculated to be equal to the individual discharge pressure value.
Determining whether or not to participate in the integrated control of the air compressor in a state in which a set value for a current value and a pressure value of the air compressor are set in advance,
Wherein the target pressure measurement value is measured when participation of the air compressor in the integrated control is determined.
A target pressure sensor for measuring a target pressure of the compressed air at a specific position by the air compressor;
An integrated control unit for integrally controlling the individual control unit and calculating a pressure increase / decrease value according to a result of comparing the target pressure measurement value measured by the target pressure sensor with a preset target pressure setting value; And
And a pressure signal controller for transmitting a virtual pressure value to the individual control unit according to the pressure increase / decrease value calculated by the integrated controller,
Wherein the integrated control unit controls the individual control unit to operate the air compressor based on the virtual pressure value transmitted from the pressure signal control unit.
The pressure-
A first input terminal to which an individual discharge pressure value is input from an individual pressure sensor of the air compressor;
A first output terminal for outputting the individual discharge pressure value to the integrated controller;
A second input terminal to which the pressure increase / decrease value calculated by the integrated control unit is inputted; And
A second output terminal for outputting the virtual pressure value obtained by adding or subtracting the pressure increase / decrease value to the individual discharge pressure value to the individual control section;
And a second air compressor.
Wherein the individual control unit controls an inlet guide vane (IGV) that adjusts an individual suction capacity of the air compressor according to a result of comparison between the virtual pressure value and an individual pressure set value predetermined by the individual control unit,
And the individual discharge pressure of the air compressor is adjusted by suction capacity control of the inlet guide vane.
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KR1020150073763A KR101744578B1 (en) | 2015-05-27 | 2015-05-27 | Method and system of controlling multi air compressor |
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KR1020150073763A KR101744578B1 (en) | 2015-05-27 | 2015-05-27 | Method and system of controlling multi air compressor |
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KR101744578B1 true KR101744578B1 (en) | 2017-06-12 |
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Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2003097451A (en) | 2001-09-25 | 2003-04-03 | Haruo Orihashi | Compressor parallel operation control device and method |
KR101127571B1 (en) | 2011-12-23 | 2012-03-23 | 에어파워코리아(주) | Control system of multiple compressor |
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Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2003097451A (en) | 2001-09-25 | 2003-04-03 | Haruo Orihashi | Compressor parallel operation control device and method |
KR101127571B1 (en) | 2011-12-23 | 2012-03-23 | 에어파워코리아(주) | Control system of multiple compressor |
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