JP4974843B2 - Compressed air control device - Google Patents

Description

  The present invention relates to a compressed air control device, and more particularly, to a compressed air control device that reduces equipment by increasing the operating rate of an air compressor.

  A gas turbine power generator installed in a plant such as a power plant has a configuration in which fuel is burned in compressed air to generate a gas, and the generator is turned using the expansion force of the gas. In plants such as power plants, many facilities and equipment that are operated by compressed air are installed in addition to gas turbine power generators. Therefore, this type of plant requires a compressed air control device that stably supplies a large amount of compressed air. In addition, in a power plant or the like, a generator is duplicated in order to improve the reliability of the generator, and when one generator fails, a spare generator is operated instead. Therefore, in order to maintain the operation of these generators, the compressed air control device is also required to have high reliability. Therefore, in the conventional compressed air control apparatus, each power generation unit is provided with a regular machine and a spare machine.

  FIG. 10 is a diagram showing a schematic configuration of a conventional compressed air control device. The compressed air control device 100 will be described with respect to the case where there are three power generation units, for example, with respect to the No. 1 unit 53 as an air compressor (hereinafter simply referred to as a compressor) 50, an output valve 51, air, A tank 52 is provided, and a compressor 54, an output valve 55, and an air tank 56 are provided as spare units. That is, one unit requires two compressors, two output valves, and two air tanks. Similarly, the No. 2 unit 60 and the No. 3 unit 67 each require three compressors, three output valves, and three air tanks, and the compressed air control device 100 requires six compressors, output valves, and six air tanks. It becomes. In this compressed air control device 100, since each unit is completely independent, it is possible to control each unit independently. On the other hand, the number of facilities increases, the facility cost increases, and those units There is a problem that the maintenance cost required for the equipment becomes high. Also, the operating rate of each compressor is not always high, and when viewed from the whole system, the required air pressure amount may not always be balanced against the number of compressors, and the compressor is not operating effectively. There is a problem.

As a conventional technique, Patent Document 1 discloses that a plurality of low-pressure side compressors and a plurality of high-pressure side compressors are operated by setting the number of operating units according to consumption amounts of the low-pressure and high-pressure air. In the method for controlling the number of compressors that supply low-pressure and high-pressure air respectively, the number of low-pressure compressors is set for the total consumption of low-pressure air and the low-pressure compressor is operated under load. Is used to control the number of operating compressors so that any one of the high-pressure compressors is capacity-controlled.
JP-A-5-60077

However, the conventional technique disclosed in Patent Document 1 is effective in reducing the power cost by efficient operation of the compressor, but has a problem that it does not contribute to the reduction in the number of installed compressors.
The present invention has been made in view of such problems, and in order to supply compressed air to a unit with a minimum compressor, the compressor is operated at the highest possible operation rate and the compressed air is stored. Provided is a compressed air control device that reduces the number of installed compressors and reduces the equipment cost and maintenance cost by supplying common compressed air to a plurality of units with the air tank outlets in parallel. For the purpose.

In order to solve such a problem, the present invention provides a compressed air control device that performs control related to starting and stopping of at least one unit constituting a plant system by air pressure, and compresses air to a predetermined pressure. Air compressor, switching means for switching an output path of the air compressor, a first air tank for storing air compressed by the air compressor, and a path side switched by the switching means. A second air tank, a pressure detection means for detecting the pressure in the first air tank, and a control means for controlling the switching means based on the pressure of the pressure detection means. When the output path of the air tank and the output path of the second air tank are respectively connected in parallel, the control means detects that the pressure detected by the pressure detection means has reached a predetermined pressure, Serial and controlling said switching means to switch the output path of the air compressor while the air compressor was continued driving of the second air chamber side.
The compressor stops supplying compressed air when the pressure in the air tank connected to the compressor reaches a predetermined pressure. As a stopping method, there are a method of stopping the motor of the compressor and a method of idling while the motor is driven. In the former case, the motor repeatedly rotates and stops each time. Depending on the frequency, however, mechanical damage to the motor or inrush current that occurs when the motor is driven frequently occurs on the power side. There is a risk of becoming. In the present invention, in order to avoid this, idle operation is performed even when the pressure in the air tank reaches a predetermined pressure, and the compressed air generated at that time is stored in the second air tank and supplied to the unit. Is. Thereby, the compressed air at the time of idling can be used effectively without wasting it.

A second aspect of the present invention provides a compressed air control apparatus that controls the start and stop of at least one unit constituting a plant system by air pressure, the air compressor compressing air to a predetermined pressure, and the air compressor Switching means for switching the output path, a first air tank for storing the air compressed by the air compressor, a second air tank provided on the path side switched by the switching means, and the first A pressure detection means for detecting the pressure in the air tank, and a control means for controlling the switching means based on the pressure of the pressure detection means, and a plurality of the air compressors are provided. When each of the first air tanks is provided, and the output path of each of the first air tanks and the output path of the second air tank are respectively connected in parallel, the control means is configured to control each of the first air tanks. The pressure from When the pressure detected by means out to detect the first air tank reaches a predetermined pressure, said output path while said air compressor was continuously driven air compressor connected with the first air tank first The switching means is controlled to switch to the second air tank side.
The present invention comprises a plurality of first air tanks and a second air tank. The second air tank is configured by collecting excess compressed air during empty operation from each of the plurality of first air tanks. It is to be stored. Thereby, the excess compressed air generated from the first air tank can be efficiently stored without waste, and the margin of the air tank can be increased.

  According to the present invention, there is provided a compressed air control device that controls the start and stop of at least one unit constituting a plant system by air pressure, the air compressor compressing air to a predetermined pressure, and the air compressor And a control unit for controlling start / stop of the air compressor, and at least one of the air compressors is operated during operation of the plant system. When at least one of the air compressors is a spare machine that replaces when the normal machine fails, and the output side of each air tank is connected in parallel, the control means operates the normal machine. Every time it detects that the predetermined time has passed, the operation is resumed by replacing the regular machine and the spare machine, so the number of compressors installed can be reduced, and the equipment cost and maintenance cost can be reduced. It is possible to reduce the number of bets.

Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings. However, the components, types, combinations, shapes, relative arrangements, and the like described in this embodiment are merely illustrative examples and not intended to limit the scope of the present invention only unless otherwise specified. .
FIG. 1 is a schematic configuration diagram of a compressed air control device according to a first embodiment of the present invention. In this example, in order to simplify the explanation, the units constituting the plant system are assumed to be three units, and the performance rate of each compressor is the same, and the operating rate required for one compressor to operate one unit is 50%. Will be described.
The compressed air control device 70 is provided with compressors (air compressors) 2, 6, 10 for compressing air to a predetermined pressure, and an output for opening and closing a compressed air path provided at the outlets of the compressors 2, 6, 10. Control units (controls) for controlling the start and stop of the valves 3, 7, 11, the air tanks 4, 8, 12 for storing the air compressed by the compressors 2, 6, 10, and the compressors 2, 6, 10 Means).

In this example, the compressors 2 and 6 are regular machines that operate while the plant system is in operation, the compressor 10 is a spare machine that substitutes when the regular machines 2 and 6 break down, and each air tank 4, 8, A case where 12 output sides are connected in parallel through a path 14 will be described. When the output valves 3, 7, and 11 are always opened and the compressors 2, 6, and 10 are allowed to be driven by the control unit 1, the pressure in the connected air tank reaches a preset pressure. Then, the operation is automatically stopped. In this example, it is only necessary to supply a compressed air amount of 150% in total for the three units. Therefore, in order to operate with two compressors as a regular machine, each unit is operated at an operating rate of 75%. Then, every time the control unit 1 detects that the operation time of the compressors 2 and 6 as the regular machines has passed a predetermined time, the controller 1 switches between the compressors 2 and 6 and the compressor 10 as the spare machine. To resume driving.
That is, this embodiment is provided with two regular machines and one spare machine, and the outlets of the air tanks 4, 8, 12 for storing the compressed air of the compressors 2, 6, 10 are connected in parallel. When it is set as the structure supplied to the unit of No. 1-No. 3, if it detects having reached the preset time from a driving | operation start, it will replace a regular machine and a spare machine, and will restart driving | operation. This makes it possible to average the frequency of use of the regular machine that is always operated and the spare machine that is almost stopped and waiting.

  Further, with the same configuration, when it is detected that there is a regular machine that has reached a preset usage time (integrated usage time) from the start of operation, the regular machine and the spare machine are replaced to resume the operation. As a result, it is possible to average the frequency of use of the regular machine that is always operated and the spare machine that is almost stopped and waiting, and to estimate the maintenance time from the usage time. The power source of the compressor is generally a motor. The maintenance time and life of the motor are determined by how long the motor has been driven. Therefore, in this embodiment, the switching time between the regular machine and the spare machine is determined by the accumulated usage time of the air compressor. Thereby, the exact maintenance time and lifetime can be estimated.

FIG. 2 is a schematic configuration diagram of a compressed air control device according to a second embodiment of the present invention. The same constituent elements are denoted by the same reference numerals as those in FIG. This compressed air control device 71 is different from FIG. 1 in that a pressure gauge (pressure detection means) 16 for detecting the pressure of the line 14 in which the output sides of the air tanks 4, 8, 12 are arranged in parallel is provided. .
That is, when all the three installed compressors 2, 6, 10 are used as regular machines, the control unit 1 determines the operating number of the compressors 2, 6, 10 based on the pressure detected by the pressure gauge 16. It is something to control. More specifically, the operation states of the output side units 5, 9, and 13 are not always constant but fluctuate one by one. The fluctuation state is possible by checking the air pressure on the output side. That is, when the pressure is high, the amount of compressed air supplied to the output side is at least good, and conversely, when the pressure drops, a large amount of compressed air supplied to the output side is required. Each compressor is designed so that the compressed air can be sufficiently supplied at a predetermined pressure even when the load on the output side is maximum. Accordingly, not all compressors need to be operated depending on the load on the output side. Therefore, in the present embodiment, the number of compressors 2, 6, 10 is controlled based on the pressure detected by the pressure gauge 16. Thereby, unnecessary driving of the compressor can be suppressed, and power consumption can be reduced. The pressure gauge 16 can be used by using a sensor whose resistance, voltage, etc. are variable according to the pressure.

FIG. 3 is a schematic configuration diagram of a compressed air control device according to a third embodiment of the present invention. The compressed air control device 72 stores the compressors 21 and 25 that compress air to a predetermined pressure, a switcher (switching unit) 31 that switches an output path of the compressor 25, and air compressed by the compressor 21. The air tanks (first air tanks) 23 and 29, the empty operation air tank (second air tank) 30 provided on the path side switched by the switch 31, and the pressure in the air tank 29 are detected. A pressure gauge (pressure detection means) 24 and a control unit (control means) 20 that controls the switch 31 based on the pressure of the pressure gauge 24 are provided. The switch 31 includes output valves 26 and 28 that can be opened and closed by a signal 32 from the control unit 1 and an inverter 27 that inverts the signal 32. The operation of the switch 31 is configured such that the output valve opens when the signal is positive and closes when the signal is negative. Therefore, when the signal 32 is positive, the output valve 28 is open and the output valve 26 is closed. In this embodiment, the operation rate of the compressor 21 is 100%, and the operation rate of the compressor 25 is 50%.
When the output path of the air tanks 23 and 29 and the output path 14 of the idle air tank 30 are connected in parallel, the control unit 20 detects that the pressure detected by the pressure gauge 24 has reached a predetermined pressure. Then, control is performed so that the output path is switched to the idling air tank 30 side while driving the compressor 25 is continued.

  That is, the compressor 25 stops supplying compressed air when the pressure in the air tank 29 connected thereto reaches a predetermined pressure. As a stopping method, there are a method of stopping the motor of the compressor 25 and a method of idling while the motor is driven. In the former case, the motor repeatedly rotates and stops each time. Depending on the frequency, however, mechanical damage to the motor or inrush current that occurs when the motor is driven frequently occurs on the power side. There is a risk of becoming. In the present embodiment, in order to avoid this, the idling operation is performed even when the pressure in the air tank 29 becomes a predetermined pressure, and the compressed air generated at that time is stored in the idling air tank 30 to store the unit 5. , 9 and 13. Thereby, the compressed air at the time of idling can be used effectively without wasting it.

FIG. 4 is a schematic configuration diagram of a compressed air control device according to the fourth embodiment of the present invention. The compressed air control device 73 includes compressors 36, 42, and 48 that compress air to a predetermined pressure, switches (switching means) 65, 66, and 67 that switch output paths of the compressors 36, 42, and 48, and compression. Air tanks 38, 44, 60 for storing air compressed by the machines 36, 42, 48, an empty operation air tank 64 provided in the path 68 switched by the switchers 65, 66, 67, and the air tank 38. , 44, 60, pressure gauges (pressure detection means) 37, 43, 49, and a control unit (control) for controlling the switches 65, 66, 67 based on the pressures of the pressure gauges 37, 43, 49 Means) 35. The configuration of the switch is the same as that of the switch 31 in FIG. The operating rate of each compressor is 75%.
The compressors 36, 42, and 48 are provided, and each compressor is provided with an air tank 38, 44, and 60. The output path 14 of the air tanks 38, 44, and 60 and the output path 69 of the idle operation air tank 64 are provided. In the case where each of them is connected in parallel, when the control unit 35 detects the air tank 38 in which the pressure detected by the pressure gauge 37 has reached a predetermined pressure from the air tanks 38, 44, 60, for example, The switch 65 is controlled so that the output path is switched to the empty operation air tank 64 while the drive of the compressor 36 is continued.
That is, this embodiment is provided with a plurality of air tanks and one empty operation air tank 64, so that excess compressed air at the time of empty operation is collectively stored in the empty operation air tank 64 from each of the plurality of air tanks. Is. Thereby, the excess compressed air generated from each air tank can be efficiently stored without waste, and the margin of the air tank can be increased.

  FIG. 5 is a flowchart for explaining the operation of the compressed air control apparatus according to the first embodiment of the present invention. A description will be given with reference to FIG. First, the compressors 2 and 6 are set as regular machines, and the compressor 10 is set as a spare machine (S1). Then, the compressors 2 and 6 which are regular machines are started to operate (S2), and the control unit 1 checks whether or not a predetermined time set in advance from the start of the operation is reached (S3), and the predetermined time must be reached. If the predetermined time has been reached (YES in S3), for example, the compressor 2 that is a regular machine and the compressor 10 that is a spare machine are switched to perform compression. The machine 2 is a spare machine, and the compressor 10 is a regular machine (S4). Thereafter, the process returns to step S2 and repeats.

  FIG. 6 is a flowchart for explaining the operation of the compressed air control apparatus according to the second embodiment of the present invention. A description will be given with reference to FIG. First, the compressors 2 and 6 are set as regular machines, and the compressor 10 is set as a spare machine (S10). Then, operation of the compressors 2 and 6 which are regular machines is started (S11), and the control unit 1 checks the cumulative use time of each compressor and there is a regular machine whose cumulative use time has reached a preset switching time. If there is no regular machine that has reached the switching time (NO in S12), the process returns to step S11 to repeat the operation, and there is a regular machine that has reached the switching time. For example (YES in S12), for example, if the regular machine that has reached the switching time is the compressor 2, it is replaced with the compressor 10 that is a spare machine, the compressor 2 is a spare machine, and the compressor 10 is a regular machine. (S13). Thereafter, the process returns to step S11 and repeats.

  FIG. 7 is a flowchart for explaining the operation of the compressed air control apparatus according to the third embodiment of the present invention. This will be described with reference to FIG. First, all the compressors 2, 6, and 10 are used as regular machines, and no spare machine is set (S20). And operation of all the compressors 2, 6, and 10 which are regular machines is started (S21), and the control part 1 monitors the pressure of the pressure gauge 16, and when required air pressure is large (it is large at S23), 3 When the compressors 2, 6 and 10 are operated (S24) and the required air pressure is medium (middle at S23), the two compressors 2 and 6 are operated (S25) and the required air pressure is small. (S23 is small) One compressor 2 is operated (S26), and when a predetermined time has elapsed (YES in S27), the process returns to step S22 to repeat. In the case of two units or one unit, which compressor is selected may be determined in advance or may be selected by the method described with reference to FIGS.

  FIG. 8 is a flowchart for explaining the operation of the compressed air control apparatus according to the fourth embodiment of the present invention. This will be described with reference to FIG. First, the compressors 21 and 25 are set as regular machines, and the compressor 21 is set to operate at an operation rate of 100% and the compressor 25 is operated at an operation rate of 50% (S30). The control part 20 makes the signal 32 negative, opens the output valve 26, and stores compressed air in the air tank 29 (S31). Then, the control unit 20 monitors the pressure of the pressure gauge 24 (S32). If the pressure is lower than the predetermined pressure, the control unit 20 continues to store the compressed air in the air tank 29 (S37). The output valve 26 is closed and the output valve 28 is opened (S33). At this time, the compressor 25 is idling, and the compressed air is stored in the idling air tank 30 (S34). Thereafter, when the pressure of the pressure gauge 24 becomes equal to or lower than the predetermined pressure (YES in S35), the control unit 20 makes the signal 32 negative again, opens the output valve 26, closes the output valve 28 (S36), and air tank 29 Store compressed air.

FIG. 9 is a flowchart for explaining the operation of the compressed air control apparatus according to the fifth embodiment of the present invention. This will be described with reference to FIG. First, the compressors 36 and 42 are set as regular machines, and the compressor 48 is set as a spare machine (S40). The control unit 35 starts the operation of the compressors 36 and 42 (S41), makes the signals 75 and 76 negative, opens the output valves 39 and 46, and stores the compressed air in the air tanks 38 and 44 (S42). The control unit 35 monitors the pressures of the pressure gauges 37 and 43 (S43). If the pressure is below a predetermined pressure, the control unit 35 continues to store the compressed air in the air tanks 38 and 44. The output valves 39 and 46 are closed and the output valves 41 and 47 are opened (S44). At this time, the compressors 36 and 42 are idling, and the compressed air is stored in the idling air tank 64 (S45). Thereafter, when the pressure of the pressure gauges 37 and 43 becomes equal to or lower than the predetermined pressure (YES in S46), the control unit 35 makes the signals 75 and 76 negative again, opens the output valves 39 and 46, and closes the output valves 41 and 47. (S47) The compressed air is stored in the air tanks 38 and 44.
In addition, since the pressures of the pressure gauges 37 and 43 do not always become the same value at the same time, the timings at which the signals 75 and 76 are output are different. When the spare compressor 48 is activated, one of the compressors 36 and 42 is stopped and the same operation as described above is repeated.

It is a schematic block diagram of the compressed air control apparatus which concerns on the 1st Embodiment of this invention. It is a schematic block diagram of the compressed air control apparatus which concerns on the 2nd Embodiment of this invention. It is a schematic block diagram of the compressed air control apparatus which concerns on the 3rd Embodiment of this invention. It is a schematic block diagram of the compressed air control apparatus which concerns on the 4th Embodiment of this invention. It is a flowchart explaining operation | movement of the compressed air control apparatus which concerns on the 1st Embodiment of this invention. It is a flowchart explaining operation | movement of the compressed air control apparatus which concerns on the 2nd Embodiment of this invention. It is a flowchart explaining operation | movement of the compressed air control apparatus which concerns on the 3rd Embodiment of this invention. It is a flowchart explaining operation | movement of the compressed air control apparatus which concerns on the 4th Embodiment of this invention. It is a flowchart explaining operation | movement of the compressed air control apparatus which concerns on the 5th Embodiment of this invention. It is a figure which shows schematic structure of the conventional compressed air control apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Control part, 2, 6, 10 Compressor 3, 7, 11 Output valve 4, 8, 12 Air tank, 5 Unit 1, 92 Unit 2, 133 Unit, 70 Compressed air control apparatus

Claims (2)

A compressed air control device that performs control related to starting and stopping of at least one unit constituting a plant system by air pressure,
An air compressor that compresses air to a predetermined pressure, a switching unit that switches an output path of the air compressor, a first air tank that stores air compressed by the air compressor, and the switching unit. A second air tank provided on the path side, a pressure detection means for detecting the pressure in the first air tank, a control means for controlling the switching means based on the pressure of the pressure detection means, With
When the output path of the first air tank and the output path of the second air tank are respectively connected in parallel,
When the control means detects that the pressure detected by the pressure detection means has reached a predetermined pressure, the control means moves the output path of the air compressor to the second air tank side while continuing to drive the air compressor. The compressed air control device, wherein the switching means is controlled to switch to A compressed air control device that performs control related to starting and stopping of at least one unit constituting a plant system by air pressure,
An air compressor that compresses air to a predetermined pressure, a switching unit that switches an output path of the air compressor, a first air tank that stores air compressed by the air compressor, and the switching unit. A second air tank provided on the path side, a pressure detection means for detecting the pressure in the first air tank, a control means for controlling the switching means based on the pressure of the pressure detection means, With
A plurality of the air compressors are provided, each air compressor is provided with the first air tank, and the output path of each first air tank and the output path of the second air tank are respectively connected in parallel. If
When the control means detects the first air tank in which the pressure detected by the pressure detection means has reached a predetermined pressure from among the first air tanks, the air compression connected to the first air tank compressed air control device, characterized in that the output path while said air compressor was continued for controlling said switching means to switch to the second air chamber side drive of the machine.

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