JP4496886B2 - Operation method of turbo compressor system - Google Patents

Description

  The present invention relates to a method for operating a turbo compressor system using a plurality of turbo compressors.

  An example of performing unit control operation using a plurality of turbo compressors is described in Patent Document 1. The system described in this publication aims to prevent the pressure of the pumped air from fluctuating even if a tank for storing compressed air is omitted in the compressor equipment. To achieve this objective, the compressor equipment selects the flow meter that detects the pumping flow rate and the number of compressors required according to the pumping flow rate, and loads, unloads, or starts and stops each compressor. It has a unit control panel. Each compressor has a suction throttle valve, and by adjusting the opening of the suction throttle valve, constant pressure control is possible. Further, in a capacity where the suction throttle control cannot be used, a part of the pumping gas is discharged to keep the pumping pressure substantially constant.

  In Patent Document 2, the number of turbo compressors is controlled by combining one turbo compressor and a plurality of positive displacement compressors. When the turbo compressor is controlled at a constant wind pressure, the rotational speed control pressure of the turbo compressor is controlled by the positive displacement compressor. It is described that the pressure is lower than the set pressure for opening the vent valve, and the set pressure for opening the vent valve of the turbo compressor is set higher than the set pressure for opening the vent valve of the positive displacement compressor.

JP-A-6-249190

Japanese Patent Laid-Open No. 11-303792

  In the compressor system described in Patent Document 1, an optimum operating unit is selected from a plurality of compressors having different capacities and detected gas flow rates, and the operation is stopped. When one compressor cannot be operated due to unforeseen circumstances, the entire system must be stopped. In addition, since the compressor to be operated for each flow rate is determined, the compressor must be frequently started or stopped according to the increase or decrease of the flow rate.

  However, frequent start and stop as a characteristic of the turbo compressor causes a failure and a decrease in life. On the contrary, when the load hardly changes, that is, when the flow rate is constant, only a specific compressor operates, a compressor that does not operate at all occurs, and the operation time changes between the compressors. This is undesirable because it significantly shortens the maintenance period of the compressor system.

  The compressor system described in Patent Document 2 uses a compressor having different characteristics such as a turbo type and a volume type. In general, the discharge pressure of a turbo compressor is low, and the discharge pressure of a positive displacement compressor is high. Therefore, it is difficult to form the best combination according to the pressure level of the demand source.

  The present invention has been made in view of the above-mentioned problems of the prior art, and its purpose is to use a suction valve and a vent valve to control the number of turbo compressors in a system in which a malfunction occurs in the operating turbo compressor. The purpose is to provide a highly reliable system that can support expansion and the like. Another object is to improve reliability by reducing the number of times the turbo compressor is started and stopped.

A feature of the present invention for achieving the above object is that a plurality of turbo compressors each having a variable flow rate suction valve on the suction side and a turbo compressor having a discharge valve capable of discharging working gas on the discharge side are connected in parallel. In an operation method of a turbo compressor system in which capacity control is performed only by a plurality of turbo compressors, each of the plurality of turbo compressors includes a maximum operation mode, a suction throttle operation mode, a minimum operation mode, and a partial load operation mode. And the unload operation mode are combined, and the maximum operation mode is an operation mode in which the suction valve is at a maximum angle or fully opened and the discharge valve is fully closed, and the suction throttle operation mode is It is an operation mode in which the valve opening of the suction valve is changed and the discharge valve is fully closed, and the minimum operation mode is a minimum angle at which the opening of the suction valve does not cause surging. And the partial load operation mode is a mode in which a new compressor is additionally operated in addition to the operating compressor, and the additional operation of the compressor is performed. It is an operation mode in which the suction valve is set to a minimum angle that does not cause surging and the discharge valve of the compressor is opened, and the unload operation mode is set to a minimum angle that does not cause surging. In addition, in each of these operation modes, the suction valve and the air discharge valve are subjected to PI control or PID control so that each turbo compressor has a predetermined discharge pressure. If one of a plurality of turbo compressors is set as a flow controller, and the flow rate required for this flow controller is equal to or greater than the maximum operation mode, the number of units is controlled. If the other turbo compressor in operation is in the minimum operation mode, the turbo compressor in this minimum operation mode is newly set as a flow controller and the flow rate up to that time is checked. If the controller is set to the maximum operation mode and all other operating turbo compressors are in the maximum operation mode, the stopped turbo compressor is started in the maximum operation mode and the flow controller is set to the partial load operation mode or The operation is performed in the suction throttle operation mode.

Another feature of the present invention that achieves the above object is that a plurality of turbo compressors each having a variable flow rate suction valve on the suction side and a plurality of turbo compressors having a discharge valve capable of discharging working gas on the discharge side are connected in parallel. In the operation method of the turbo compressor system in which the capacity is controlled only by the plurality of turbo compressors, each of the plurality of turbo compressors includes a maximum operation mode, a suction throttle operation mode, a minimum operation mode, and a partial load. The operation mode is combined with an unload operation mode, and the maximum operation mode is an operation mode in which the suction valve is at a maximum angle or fully opened and the discharge valve is fully closed, and the suction throttle operation mode Is an operation mode in which the opening degree of the suction valve is changed and the ventilating valve is fully closed. In the minimum operation mode, the opening degree of the suction valve does not cause surging. It is an operation mode in which the air discharge valve is fully closed while the angle is set, and the partial load operation mode is a mode in which a new compressor is additionally operated in addition to an operating compressor, and the compressor is additionally operated. The suction valve is set to a minimum angle that does not cause surging and the discharge valve of the compressor is opened, and the unload operation mode is set to a minimum angle that does not cause surging. In addition, in each of these operation modes, the suction valve and the discharge valve are subjected to PI control or PID control, and a predetermined discharge pressure predetermined for each turbo compressor is set. If one of the multiple turbo compressors is set as the flow controller, and the flow required for this flow controller becomes the flow in the partial load operation mode that opens the ventilating valve, The control panel checks the operating status of the other turbo compressors, and if the other turbo compressors in operation are in the minimum operating mode, all turbo compressors in the minimum operating mode are set to the maximum operating mode and the flow controller is turned on. The partial load operation mode or the unload operation mode is set to stop the operation if there is a turbo compressor in which the unload operation has continued for a predetermined time.

Still another feature of the present invention that achieves the above object is that a plurality of turbo compressors each having a variable flow rate suction valve on the suction side and a turbo compressor having a discharge valve capable of discharging working gas on the discharge side are connected in parallel. In the operation method of the turbo compressor system in which the capacity is controlled only by the plurality of turbo compressors, each of the plurality of turbo compressors includes a maximum operation mode, a suction throttle operation mode, a minimum operation mode, and a part The load operation mode and the unload operation mode are combined to operate, and the maximum operation mode is an operation mode in which the suction valve is set to a maximum angle or fully opened, and the discharge valve is fully closed, and the suction throttle operation is performed. The mode is an operation mode in which the opening degree of the suction valve is changed and the discharge valve is fully closed, and the minimum operation mode causes surging of the opening degree of the suction valve. The partial load operation mode is a mode in which a new compressor is additionally operated in addition to the operating compressor, and the additional operation is performed. It is an operation mode in which the suction valve of the compressor is set to a minimum angle that does not cause surging and the discharge valve of the compressor is opened, and the unload operation mode is a minimum that does not cause surging of the opening of the suction valve. It is an operation mode in which the air discharge valve is fully opened while the angle is set, and in each of these operation modes, the suction valve and the air discharge valve are PI-controlled or PID-controlled and predetermined for each turbo compressor. Control the discharge pressure so that one of the multiple turbo compressors is a flow controller, and the flow required for this flow controller is the flow in the unload operation mode where the vent valve is fully open. The unit control panel checks the operation status of the other turbo compressors. If the other turbo compressor in operation is in the maximum operation mode or the minimum operation mode, the turbo compressor is determined as the flow controller and The flow controller is set to the unload operation mode, and if there is a turbo compressor in which the unload operation has continued for a predetermined time, the operation is stopped.

  According to the present invention, since the turbo compressor to be started or stopped can be arbitrarily set without corresponding to the used flow rate, it is possible to easily cope with a failure or expansion of the turbo compressor. In addition, the number of starting and stopping can be reduced. Furthermore, since the target pressure of the compressor operating at the maximum opening is the allowable maximum pressure, even if the demand source's required flow rate decreases and the demand source's pressure increases rapidly, the luck point at the maximum opening Simply reducing the target pressure of the compressor is reducing the pressure at the demand source.

  Hereinafter, an embodiment of a compressor system 100 according to the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of the compressor system 100. In the present embodiment, the compressor system 100 includes three turbo compressors 10, 20, and 30 having the same specifications. On the suction side of each turbo compressor body 13, 23, 33, inlet guide vanes (hereinafter referred to as suction valves) 12, 22, 32 are attached. Branching from the discharge pipes 17, 27, and 37 of the turbo compressor bodies 13, 23, and 33, the air discharge valves 14, 24, and 34 are attached. Check valves 15, 25, and 35 are interposed in the discharge pipes 17, 27, and 37, and downstream sides of the check valves 15, 25, and 35 are connected to the collective pipe 41. On the downstream side of the check valves 15, 25, 35 and upstream of the collecting pipe 41, a pressure detection device that detects the pressure of the gas discharged from each turbo compressor body 13, 23, 33 is attached. Yes. Furthermore, a discharge pressure detector that detects the overall discharge pressure of the gas discharged from the compressor system 100 is provided in the middle of the collective pipe 41 and downstream of the connecting portion with the discharge pipe 37 of the turbo compressor 30. It is attached.

  Each turbo compressor 10, 20, 30 is provided with a compressor control panel 11, 21, 31 that controls the turbo compressor body 13, 23, 33. Each compressor control board 11, 21, 31 has a turbo compressor detected by pressure detection devices 16, 26, 36 corresponding to the turbo compressor 10, 20, 30 to which the compressor control board 11, 22, 33 belongs. The discharge gas pressure of the main bodies 13, 23, 33 is input. The compressor control panels 11, 21, 31 output opening commands to the suction valves 12, 22, 32 and the air discharge valves 14, 24, 34.

  The compressor control panels 11, 21, and 31 are connected to the number control panel 1, and the discharge pressure of the compressor system 100 detected by the discharge pressure detector 2 provided in the collective piping 41 is input to the number control panel 1. Is done. As shown in FIG. 2, the operation state of each of the turbo compressors 10, 20, and 30 during the air discharge operation, the maximum opening operation, the minimum operation, etc. from the compressor control panels 11, 21, and 31 is the number control panel. 1 is transmitted. On the other hand, commands such as an operation or stop command, unloading, target pressure switching, and minimum operation of each turbo compressor 10, 20, and 30 are transmitted from the unit control panel 1 to the compressor control panels 11, 21, and 31. .

  In the compressor system 100 of this embodiment configured as described above, the working gas sucked through the suction valves 12, 22, 32 is compressed by the turbo compressor body 13 to become high pressure, and the check valves 15, 25, 35 to the demand source via the collective pipe 41. The pressure of the demand source is detected by the discharge pressure detector 2 of the collecting pipe 41. The discharge pressures of the turbo compressor bodies 13, 23, and 33 detected by the pressure detection devices 16, 26, and 36, and the targets that will be described in detail later. PI control or PID control is performed from the pressure deviation to adjust the pumping amount of the working gas.

  When the amount of pumping gas is small, the opening degree of the suction valves 12, 22, 32 is kept at the minimum opening degree where surging does not occur. And the opening amount of the ventilating valves 14, 24, and 34 is adjusted, the amount of surplus gas discarded is adjusted, and the gas amount pumped to the demand source is controlled. When the amount of gas consumed at the demand source exceeds a predetermined amount, the blow-off valves 16, 26, 36 are held in a fully closed state, the opening degree of the suction valves 12, 22, 32 is adjusted, and the turbo compressor body 13 , 23, 33 to adjust the amount of working gas sucked. When ventilating control is performed by opening the ventilating valves 14, 24, 34, the power is constant regardless of the pumping flow rate of the working gas sent to the demand source. When suction throttle control is performed to change the suction valves 12, 22, and 32 from a minimum opening degree where surging does not occur to a fully open position, the power is in accordance with the pumping flow rate of the working gas sent to the demand source. Therefore, in order to perform an energy saving operation, the operation time of the air discharge control is reduced as much as possible.

In FIG. 3, the example of the operation mode of the turbo compressors 10, 20, and 30 is shown. The horizontal axis represents the reference flow rate Qc of the working gas consumed in the turbo compressor system 100, and the vertical axis represents the flow rate Qg of the working gas discharged from the turbo compressor bodies 13, 23, 33. In the horizontal axis, ULD indicates the unload operation described below. MIN is the minimum operation at the operating point on the surge line (actually slightly higher flow rate side than the surge line with a margin), and MAX is the maximum air flow. Driving. Between ULD and MIN is PLD, and between MIN and MAX is CC. Each of these operation modes will be described below.
(1) Unload operation (ULD)
In this mode, the consumption gas amount of the demand source is small, and the compressed gas generated in the turbo compressor 10 (20, 30) is thrown away with the vent valve 14 (24, 34) fully opened. Since the turbo compressor main body 13 (23, 33) takes a longer time from the start-up to a stable operation as compared with a capacity-type compressor or the like, it is desirable to reduce the number of start-ups as much as possible. For this reason, the turbo compressor main body 13 (23, 33) is continuously operated even when the amount of gas consumed by the compressor system 100 is reduced.

However, since the compressor main body 13 (23, 33) must be operated at a flow rate that is equal to or greater than the surging limit, the pressure of the compressor system 100 increases excessively when the vent valve 14 (24, 34) is closed. Therefore, in order to prevent an increase in pressure, the vent valve 14 (24, 34) is fully opened. At this time, the opening degree β of the suction valve 12 (22, 32) is set to the allowable minimum opening degree βmin. The unload operation (ULD) is an operation in which all the work performed by the turbo compressors 10, 20, and 30 is wasted, so it is desirable to avoid it as much as possible. Therefore, when the unload operation (ULD) is continued for a predetermined time, in this embodiment, for 10 minutes or more, the turbo compressor main body 13 (23, 33) is stopped.
(2) Partial load operation (PLD)
Even if a turbo compressor that is performing capacity adjustment operation described later reaches maximum capacity operation, when starting a turbo compressor that still has a large amount of gas consumption, or when one compressor is activated There is no mode to start the first compressor. However, this mode is not necessarily required when starting the first machine. When the newly started turbo compressor 10 (20, 30) is operated at the maximum capacity, if the generated flow rate is too high and the pressure of the compressor system 100 may rise abnormally, the additionally started turbo compressor Only a part of the compressed gas discharged from 10 (20, 30) is supplied to the demand source. In this case, the blower valve 14 (24, 34) of the additionally activated turbo compressor 10 (20, 30) is opened by an appropriate amount, and the amount of compressed gas generated by the turbo compressor 10 (20, 30) and the consumption gas Balance the amount and the amount of breezes. The opening β of the suction valve 12 (22, 32) at this time is β = βmin.
(3) Minimum operation (MIN)
Although the amount of gas consumption is not so much, it is a mode in which the generated gas amount becomes smaller than the consumed gas amount when one turbo compressor 10 (20, 30) in operation is stopped or unloaded. . The opening degree β of the suction valve 12 (22, 32) is set to a minimum opening degree βmin at which surging does not occur, and the air discharge valve 14 (24, 34) is fully closed.
(4) Suction throttle operation (CC)
Gas consumption by changing the valve opening β of the suction valve 12 (22, 32) provided on the suction side of the turbo compressor main body 13 (23, 33) in operation in a larger flow rate range than the operating point causing surging. This is an operation mode for generating compressed gas corresponding to the amount. The amount of gas consumed by the demand source is relatively large. The vent valve 14 (24, 34) is fully closed.
(5) Maximum operation (MAX)
This is the upper limit of the suction throttle operation. The valve opening β of the suction valve 12 (22, 32) is set to the maximum opening β = βmax or fully open. The vent valve 14 (24, 34) is fully closed. Even if the gas consumption of the demand source increases, the compressor 10 (20, 30) that has reached the maximum operation (MAX) cannot generate more compressed gas. In such a case, the operation mode of the other turbo compressor 20 (30, 10) is changed.

The compressor system 100 sets such five operation modes and stop modes in the respective turbo compressors 10, 20, and 30, and corresponds to the consumption gas amount of the demand source. A procedure for switching the operation mode of the turbo compressors 10, 20, and 30 in the embodiment shown in FIG. 1 in which three turbo compressors 10, 20, and 30 are connected in parallel will be described with reference to FIGS. To do. FIG. 4 is a flowchart of the operation of the compressor system 100, and FIG. 5 is a diagram showing the operating state of each turbo compressor 10, 20, 30. In FIG. 5, the mode change when two turbo compressors are in operation will be described. The turbo compressor that mainly adjusts the capacity is No. I, the turbo compressor that is currently maintained in a constant state is No. II, and the stopped compressor is No. III. As described above, the No. I machine does not necessarily correspond to the turbo compressor 10, and the turbo compressor 10 can be a No. II machine or an No. III machine depending on the situation. Also, the compressor that is stopped next when the amount of consumed gas is reduced is called Unit II.
(Case A)
Two turbo compressors 10 and 20 (30) are operating. Any one of the turbo compressors 10 and 20 (30) is in a suction throttle operation. This compressor is referred to as Unit I. Unit I apparently acts as a capacity adjustment (CC) machine. Unit II is either unloaded (ULD), minimum (MIN), or maximum (MAX). Unit III has stopped. In this state, when the gas consumption of the demand source increases, the capacity regulator No. I increases the opening β of the suction valve 12 (22, 32), and finally reaches the maximum opening βmax (maximum operation ( Max) (step A1).

  Furthermore, since it is required to increase the amount of compressed gas generated, the unit control panel 1 checks the operating state of the No. II and No. III units. It is checked whether Unit II or Unit III is in minimum operation (MIN) (Step A2). If Unit II is in minimum operation (MIN), Unit I is held at maximum operation (MAX) (Step A3). ), II is set as a capacity adjuster (step A4). In the subsequent control of the turbo compressor, this II machine is treated as a new I machine.

  In Step A2, when the No. II machine is not in the minimum operation (MIN), it is checked whether the No. II machine is in the maximum operation (MAX) (Step A6). If it is the maximum operation (MAX) (step A7), it is checked whether the state of the No. III machine is an unload operation (ULD) (step A9). Since Unit III is set to stop, it jumps to Step A12 and starts Unit III. On the other hand, if Unit II is not in maximum operation (MAX) or minimum operation (MIN), it is assumed that Unit II is activated, so in Step A9 it is determined that it is unloading (ULD), and there is a margin in compressed gas generation capacity. A certain Unit II is operated at maximum (MAX). Then, Unit I is operated as a capacity adjuster.

When the compressed gas amount is insufficient with the capacity of Units I and II, Unit III is started. At the start of Unit III, the Unit II that is already operating at its maximum capacity (MAX) maintains the maximum operation (MAX) and the Unit III is also operated at the maximum (MAX). Unit I, which is a capacity adjuster, reduces the discharge flow rate to correspond to the consumption gas amount of the demand source. That is, at the initial stage of capacity adjustment, the No. I machine is partially loaded (PLD), and thereafter capacity adjusted (CC). Thereby, the fluctuation | variation of the discharge pressure which the discharge pressure detector 2 of the compressor system 100 resulting from a rapid flow rate change detects is prevented.
(Case B)
The gas consumption of the demand source is reduced, and the suction valve opening β of the No. I machine that has been operating as a capacity regulator has reached βmin and is in a minimum operation (MIN) (step B1). Unit I is set to the minimum operation (MIN) machine (step B2). The number control panel 1 checks whether the No. II machine is operating at maximum (MAX) (step B3). If Unit II is operating at its maximum (MAX), set Unit II as the capacity adjuster for suction throttle operation (CC) and set it as the new Unit I (step B4). If Unit II is not operating at the maximum (MAX), the suction throttle operation (CC), the minimum operation (MIN), or the unload operation (ULD) is set as the capacity adjuster. At that time, a set operation mode is determined in accordance with the operation state of Unit II until then (step B6).
(Case C)
In the case B, the consumption gas flow rate is further reduced, and the partial load operation (PLD) is performed by reducing the flow rate of the No. I machine that is the capacity regulator. Since the flow rate required for Unit I is a flow rate below the minimum operation (MIN) with the discharge valve 14 (24, 34) fully closed, the opening β of the suction valve 12 (22, 32) is set to β = βmin, the vent valve 14 (24, 34) is opened, and the ventilating operation is performed (step C1). In this embodiment, the surging start flow rate is 70% of the maximum flow rate. That is, the gas consumption of the demand source is reduced, and the amount of compressed gas required for the turbo compressor body 13 (23, 33) is less than 70% of the maximum compressed gas flow rate of the turbo compressor body 13 (23, 33). Then, the turbo compressor main body 13 (23, 33) is partially loaded.

  By the way, the partial load operation (PLD) is to discard a part of the compressed gas generated in the turbo compressor body 13 (23, 33), and the unload operation (ULD) is to discard all of the generated compressed gas. Therefore, it is desirable to shorten the operation time of partial load operation (PLD) and unload operation (ULD) as much as possible. As described above, when the unload operation (ULD) is started, the turbo compressor main body 13 (23, 33) is stopped if the state continues for 10 minutes or longer, so the partial load operation (PLD) is continued for a long time. If the turbo compressor body 13 (23, 33) is stopped by entering the unload operation (ULD) as soon as possible, the power consumption can be reduced.

  In this embodiment, the turbo compressor main body 23 (33, 13) of the operating No. II or III is operated at the maximum capacity, the flow rate required for the No. I unit is reduced as much as possible, and the unload operation (ULD) state is achieved. To be. The unit control panel 1 checks whether the No. II machine is operating at the maximum (MAX) (step C2). If Unit II is in maximum operation (MAX) (step C3), the discharge flow rate of the other compressors in operation cannot be increased any more. Therefore, the unit control panel 1 checks whether the No. III machine is in the minimum operation (MIN) (step C5).

  If the No. II machine is not at the maximum operation (MAX) in Step C2, the unit control panel 1 checks whether the No. II machine is operating at the minimum (Step C5). If Unit II is not operating at the minimum in Step C5, Unit II is unloading (ULD) and is waiting to stop, so the flow control of the turbo compressor bodies 13 and 23 (33) cannot be performed any more. End the flow control.

  If Unit II is in minimum operation (MIN), the discharge flow rate of Unit II can be increased and the discharge flow rate of Unit I can be decreased. Therefore, the maximum operation (MAX) of Unit II is performed, the opening degree of the discharge valve 14 (24, 34) of the Unit I is increased, and the amount of discharge is increased (Step C6). In this case C operation, the increase in the flow rate of Unit II and the increase in the air discharge amount of Unit I are synchronized to prevent sudden flow rate changes.

For example, when the flow rate required for Unit I is 30% of the maximum flow rate and Unit II is in the minimum operation (MIN), the current flow rate of Unit II is 70% of the maximum flow rate. Therefore, if the Unit II is set to the maximum operation (MAX), the flow rate of the Unit I becomes 0% and the operation can be shifted to the unload operation (ULD). In the present embodiment, since it is assumed that three turbo compressors 10, 20, and 30 having the same capacity are used, the rate at which unload operation (ULD) and partial load operation (PLD) can be avoided by case C. There is little and the reduction effect of the power consumption by case C is few. However, when four or more turbo compressors are used, the generation ratio of the compressors to be unloaded (ULD) is remarkably increased, so that power consumption can be reduced.
(Case D)
This is a case where the amount of gas consumed by the demand source is reduced and the amount of gas required for the compressor body 13 (23, 33) is further reduced than in the case C. The No. I machine, which is a capacity adjuster, has shifted to the unload operation (ULD) in which the discharge valve 14 (24, 34) is fully opened beyond the partial load operation (PLD) (step D1). Therefore, the No. I machine is set as an unloading machine (step D2), and the unit control panel 1 checks whether the No. II machine is operating at the maximum (MAX) (step D3). If Unit II is in maximum operation (MAX), Unit II is set as a new Unit I as a capacity adjuster (step D4). If Unit II is not operating at the maximum (MAX), it is a minimum operation (MIN) or an unload operation (ULD) waiting for a stop. If it is the minimum operation (MIN), the capacity controller is set as the new I machine (step D6). If it is an unload operation (ULD), the unload operation (ULD) is continued as it is, and when the unload operation (ULD) is started for 10 minutes, the No. II machine is stopped.
(Case E)
When the unload operation (ULD) continues for a predetermined time or longer, the turbo compressor body 13 (23, 33) is stopped. Regardless of whether or not it is a capacity adjuster, when the unload operation (ULD) of all the turbo compressor bodies 13, 23, 33 continues for 10 minutes (step E1), the unload operation (ULD) is performed. The turbo compressor main body 13 (23, 33) that has continued for 10 minutes or more is stopped. Thereby, while reducing the amount of discharged gas, power consumption is reduced.

  As described above, when three units of equal capacity turbo compressors are connected in parallel to control the number of units, by operating in combination with the operation mode of each turbo compressor, reducing the amount of discharged air and reducing power consumption Stated. It goes without saying that the present invention can be applied not only to the case where the capacities of the respective turbo compressors are equal, but also to combinations of turbo compressors having different capacities. In that case, according to the compressed gas usage pattern of a demand source, each operation mode can be combined so that starting / stopping of each compressor becomes comparable, and the maintenance time of each compressor can be adjusted. As a result, maintenance can be performed in the same cycle for each compressor.

  The present invention can also be applied to a compressor system having four or more turbo compressors or only two turbo compressors. As described above, the larger the number of compressors, the more advantageous the case C operation mode setting can be, and the power consumption can be reduced. Furthermore, although the limit of the unload operation duration is set to 10 minutes, it is desirable to determine this time as appropriate according to the usage pattern of the compressed gas at the demand source. In any case, since the turbo compressor is unsuitable for frequent start / stop, the operation pattern may be set so as to suppress start / stop as much as possible.

1 is a block diagram of an embodiment of a turbo compressor system according to the present invention. The figure explaining the signal transmission of a control system. The figure explaining the operation mode of a turbo compressor. The operation | movement flowchart of the turbo compressor system shown in FIG. The figure explaining the operation mode state of each turbo compressor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Number control panel, 2 ... Discharge pressure detector, 10 ... Turbo compressor, 11 ... Compressor control panel, 12 ... Suction valve, 13 ... Compressor main body, 14 ... Air discharge valve, 15 ... Check valve, 16 DESCRIPTION OF SYMBOLS ... Pressure detection device, 20 ... Turbo compressor, 21 ... Compressor control panel, 22 ... Suction valve, 23 ... Compressor body, 24 ... Air discharge valve, 25 ... Check valve, 26 ... Pressure detection device, 30 ... Turbo Compressor, 31 ... compressor control panel, 32 ... suction valve, 33 ... compressor body, 34 ... venting valve, 35 ... check valve, 36 ... pressure detection device.

Claims (3)

Turbos that each have a plurality of turbo compressors connected in parallel, each with a suction valve with variable flow rate on the suction side and a discharge valve that can discharge the working gas on the discharge side. In the operation method of the compressor system,
Each of the plurality of turbo compressors is operated by combining a maximum operation mode, a suction throttle operation mode, a minimum operation mode, a partial load operation mode, and an unload operation mode ,
The maximum operation mode is an operation mode in which the suction valve is at a maximum angle or fully opened, and the discharge valve is fully closed,
The suction throttle operation mode is an operation mode in which the opening degree of the suction valve is changed and the discharge valve is fully closed,
The minimum operation mode is an operation mode in which the opening degree of the suction valve is set to a minimum angle that does not cause surging and the discharge valve is fully closed,
The partial load operation mode is a mode in which a compressor is additionally operated in addition to the operating compressor, and the suction valve of the compressor to be additionally operated is set to a minimum angle that does not cause surging and the compressor is operated. An operation mode for opening the vent valve,
The unload operation mode is an operation mode in which the opening degree of the suction valve is set to a minimum angle that does not cause surging and the discharge valve is fully opened.
In each of these operation modes, PI control or PID control is performed on the suction valve and the discharge valve to control each turbo compressor so as to have a predetermined discharge pressure ,
If one of the multiple turbo compressors is set as a flow controller, and the flow rate required for this flow controller is equal to or greater than the flow in the maximum operation mode, the unit control panel will operate the other turbo compressors. Check
If the other turbo compressor in operation is in the minimum operation mode, the turbo compressor in this minimum operation mode is newly set as a flow controller, and the previous flow controller is set to the maximum operation mode.
When all other turbo compressors in operation are in the maximum operation mode, the stopped turbo compressor is started in the maximum operation mode and the flow controller is operated in the partial load operation mode or the suction throttle operation mode. The operation method of the turbo compressor system.
Turbos that each have a plurality of turbo compressors connected in parallel, each with a suction valve with variable flow rate on the suction side and a discharge valve that can discharge the working gas on the discharge side. In the operation method of the compressor system,
  Each of the plurality of turbo compressors is operated by combining a maximum operation mode, a suction throttle operation mode, a minimum operation mode, a partial load operation mode, and an unload operation mode,
  The maximum operation mode is an operation mode in which the suction valve is at a maximum angle or fully opened, and the discharge valve is fully closed,
  The suction throttle operation mode is an operation mode in which the opening degree of the suction valve is changed and the discharge valve is fully closed,
  The minimum operation mode is an operation mode in which the opening degree of the suction valve is set to a minimum angle that does not cause surging and the discharge valve is fully closed,
  The partial load operation mode is a mode in which a compressor is additionally operated in addition to the operating compressor, and the suction valve of the compressor to be additionally operated is set to a minimum angle that does not cause surging and the compressor is operated. An operation mode for opening the vent valve,
  The unload operation mode is an operation mode in which the opening degree of the suction valve is set to a minimum angle that does not cause surging and the discharge valve is fully opened.
  In each of these operation modes, PI control or PID control is performed on the suction valve and the discharge valve to control each turbo compressor so as to have a predetermined discharge pressure,
  One of the multiple turbo compressors is set as a flow controller, and when the flow rate required for this flow controller reaches the flow rate of the partial load operation mode that opens the vent valve, the unit control panel is set to another turbo compressor. Check the driving status of
  If other turbo compressors in operation are in the minimum operation mode, all turbo compressors in the minimum operation mode are set to the maximum operation mode and the flow controller is set to the partial load operation mode or the unload operation mode.
  An operation method of a turbo compressor system, characterized in that the operation is stopped if there is a turbo compressor that has been unloaded for a predetermined time.
Turbos that each have a plurality of turbo compressors connected in parallel, each with a suction valve with variable flow rate on the suction side and a discharge valve that can discharge the working gas on the discharge side. In the operation method of the compressor system,
  Each of the plurality of turbo compressors is operated by combining a maximum operation mode, a suction throttle operation mode, a minimum operation mode, a partial load operation mode, and an unload operation mode,
  The maximum operation mode is an operation mode in which the suction valve is at a maximum angle or fully opened, and the discharge valve is fully closed,
  The suction throttle operation mode is an operation mode in which the opening degree of the suction valve is changed and the discharge valve is fully closed,
  The minimum operation mode is an operation mode in which the opening degree of the suction valve is set to a minimum angle that does not cause surging and the discharge valve is fully closed,
  The partial load operation mode is a mode in which a compressor is additionally operated in addition to the operating compressor, and the suction valve of the compressor to be additionally operated is set to a minimum angle that does not cause surging and the compressor is operated. An operation mode for opening the vent valve,
  The unload operation mode is an operation mode in which the opening degree of the suction valve is set to a minimum angle that does not cause surging and the discharge valve is fully opened.
  In each of these operation modes, PI control or PID control is performed on the suction valve and the discharge valve to control each turbo compressor so as to have a predetermined discharge pressure,
  If one of the multiple turbo compressors is set as a flow controller, and the flow required for this flow controller becomes the flow in the unload operation mode that fully opens the vent valve, the unit control panel will switch to another turbo Check the operating condition of the compressor,
  If the other turbo compressor in operation is in the maximum operation mode or the minimum operation mode, the turbo compressor is set as the flow controller and the previous flow controller is set in the unload operation mode.
  An operation method of a turbo compressor system, characterized in that the operation is stopped if there is a turbo compressor that has been unloaded for a predetermined time.

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