JP2013117168A - Rotating machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the generation of "surge", in a rotating machine in which a plurality of compression stages are arranged in an axial direction of a rotor, the compression stages being configured of a moving vane and a stator vane provided on a channel to be next to one another in the axial direction.SOLUTION: The rotating machine 1 includes: an angle adjustment mechanism 60 that varies an angle of the stator vane 40 to the axis C1 direction of the rotor 20; a pressure sensor 70 that detects a pressure of the channel FP; and a control device that controls the angle adjustment mechanism 60 on the basis of a pressure value output from the pressure sensor 70. The plurality of compression stages 50 are divided into a front stage side positioned at the upstream of the channel FP and a rear stage side positioned at the downstream of the channel FP. The pressure sensor 70 is located at at least the rear stage side.

Description

  The present invention relates to a rotary machine such as a compressor or a blower.

Conventionally, when starting a rotary machine such as an axial-flow compressor or blower (at the time of startup), a rotor (impeller) having rotor blades attached to a rotor body (hub) is rotated. A predetermined time is required until the rotational speed reaches a predetermined rotational speed (rated rotational speed). In addition, when the rotating machine is stopped (when stopped), a predetermined time is similarly required until the rotational speed of the rotor becomes zero (stopped state) from the rated rotational speed.
When starting and stopping the rotating machine, a phenomenon called “spinning stall” is likely to occur in the flow path of the rotating machine with the rotor attached. There arises a problem that the entire rotating machine including a rotating body, a stationary body such as a stationary blade or a casing vibrates.

  As a conventional technique for suppressing the occurrence of “turning stall”, for example, as described in Patent Document 1, a stationary blade is provided so that the stationary blade angle with respect to the axial direction of the rotor is variable, and It has been considered to provide a pressure sensor (pressure transmitter) for detecting the pressure in the flow path in a portion near the inlet of the flow path. Then, the angle of the stationary blade is adjusted based on the detection result of the pressure sensor so that the pressure fluctuation detected by the pressure sensor does not become the pressure fluctuation that causes the turning stall phenomenon described above.

Japanese Utility Model Publication No. 61-18239

By the way, in a rotating machine such as a compressor or a blower, when the rotor rotates at the rated rotational speed (at the time of rated operation), for example, the piping shape connected to the outlet of the flow path of the rotating machine, or this piping For example, as shown in FIG. 5, the pressure P, temperature, and humidity of the fluid on the channel outlet X1 side are likely to vary depending on the opening degree of the valve attached to the valve. Since the fluid is sucked into the flow path from the outside through the flow path inlet X0, the pressure P, temperature, and humidity of the fluid at the flow path inlet X0 depend on the state outside the flow path, and the operating state of the rotary machine Not affected.
When the pressure P on the channel outlet X1 side increases excessively, there is a problem that a malfunction phenomenon called “surge” occurs on the channel outlet X1 side.

Here, “surge” generated during rated operation will be described. In a rotating machine during rated operation, for example, as shown in FIG. 6, when the pressure P on the flow path outlet side increases (in the direction indicated by the arrow in FIG. 6), from the flow path outlet of the rotary machine to the outside per unit time. In other words, the flow rate Q flowing out of the shaft body decreases, in other words, the flow velocity of the fluid flowing in the axial direction of the shaft body decreases at or near the flow path outlet.
During rated operation, the speed at which the rotor blades move in the circumferential direction of the shaft body (rotational speed of the rotor) is constant, so that the flow rate in the axial direction of the fluid is reduced as described above. The incident angle of the fluid with respect to the moving blade (the chord) disposed on the blade increases, in other words, the relative angle of attack of the moving blade with respect to the fluid flow direction increases. As a result, “separation” occurs in which the fluid does not flow along the blade surface of the rotor blade. Note that this separation phenomenon occurs when the relationship between the flow rate Q and the pressure P in FIG. 6 moves to the B point side from the A point (the maximum value of the pressure P).

“Surge” is a phenomenon in which the moving blade and the shaft body vibrate greatly on the outlet side of the flow channel due to the above-described peeling phenomenon. In FIG. 6, the point B indicates the occurrence point of “surge”. When such a large vibration occurs, the rotating machine may fall into an inoperable state. Therefore, there is a demand for a method capable of suppressing the occurrence of “surge” in a rotating machine.
In the configuration described in Patent Document 1, since the angle of the stationary blade can be adjusted, the flow rate of the fluid flowing in the axial direction can be adjusted, but the pressure sensor is flowed for the purpose of avoiding the rotating stall phenomenon. Since the pressure sensor is provided on the path inlet side, the pressure sensor cannot detect a pressure suggesting the occurrence of “surge” on the channel outlet side. That is, the occurrence of “surge” cannot be suppressed.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a rotating machine capable of suppressing the occurrence of “surge”.

  In order to solve this problem, the rotating machine of the present invention includes a plurality of compression stages arranged in the axial direction, each composed of a moving blade and a stationary blade provided in a flow path so as to be adjacent to each other in the axial direction of the rotor. An angle adjusting mechanism that changes the angle of the stationary blade with respect to the axial direction, a pressure sensor that detects the pressure of the flow path, and a pressure value output from the pressure sensor. A control device that controls the angle adjusting mechanism, and the plurality of compression stages are divided into a front stage located on the upstream side of the flow path and a rear stage side located on the downstream side of the flow path. The pressure sensor is arranged at least on the rear stage side.

In addition, the said back | latter stage side is an area | region on the flow-path exit side rather than the intermediate position of the sequence direction (axial direction) of a some compression stage, for example. Moreover, the said front | former stage side is an area | region on the flow-path inlet side rather than the intermediate position of the sequence direction of a some compression stage, for example.
For example, when the number of stages of the compression stages is an odd number, the intermediate position is a position between a moving blade and a stationary blade constituting one compression stage located in the middle in the arrangement direction. On the other hand, when the number of compression stages is an even number, the intermediate position is a position between two adjacent compression stages in the middle of the arrangement direction.

According to the rotary machine, during the rated operation of the rotary machine, a pressure sensor arranged on the rear stage side is supplied with a pressure indicating a “surge” that is likely to occur on the rear stage side (channel outlet side) among the plurality of compression stages. Therefore, the occurrence of “surge” during rated operation of the rotating machine can be suppressed.
That is, the occurrence of “surge” is caused by the pressure increase on the rear stage side (flow path outlet side) of the plurality of compression stages. Therefore, in the rotary machine, the pressure value detected by the rear stage pressure sensor is “surge”. When the control device determines that the pressure is equal to or greater than a predetermined pressure value (surge generation pressure value; pressure value stored in advance in the control device) that indicates the occurrence of The angle of the stationary blade (its chord) may be adjusted.

More specifically, when the controller determines as described above, the flow rate of the fluid flowing in the axial direction in the flow channel (especially the flow rate flowing on the flow channel outlet side) is increased, The control device may control the angle adjusting mechanism to reduce the angle of the stationary blade with respect to the axial direction so that the detected pressure value becomes smaller than the surge generation pressure value.
By adjusting the angle of the stationary blade as described above, the occurrence of “surge” can be suppressed.

  In the rotating machine, it is preferable that a plurality of the pressure sensors arranged on the rear stage side are arranged in the axial direction.

  In the rotating machine, the pressure indicating “surge” can be detected at a plurality of positions in the axial direction on the rear stage side of the plurality of compression stages by the plurality of rear stage pressure sensors. Therefore, even if the axial length of the flow path on the rear stage side is long, the pressure that suggests the occurrence of “surge” can be easily detected and the occurrence of “surge” can be suppressed, improving reliability. can do.

In the rotating machine, the pressure sensor may be arranged on the front side.
In the above rotating machine, the pressure suggesting the occurrence of “surge” can be detected by the pressure sensor (front pressure sensor) arranged on the front side during the rated operation. It is also possible to suppress the occurrence of “surge” in FIG.

Further, in the above rotating machine, when starting or stopping, the pressure fluctuation indicating the occurrence of “rotation stall” that is likely to occur on the front side (channel inlet side) among the plurality of compression stages is caused by the front side pressure sensor. Since it can be detected, the occurrence of “turning stall” at the time of starting or stopping can be suppressed.
In order to suppress the occurrence of “turning stall”, the pressure fluctuation detected by the pressure sensor on the front stage is a predetermined pressure fluctuation (stall occurrence pressure data; suggesting the occurrence of “turning stall”). When the control device determines that the level is equal to or higher than the pressure fluctuation, the angle adjustment mechanism may be controlled by the control device to adjust the angle of the stationary blade.

More specifically, when the control device determines as described above, the upstream side pressure is increased by increasing the flow rate of the fluid flowing in the axial direction in the flow channel (particularly, the flow rate flowing on the flow channel inlet side). The control device may control the angle adjusting mechanism to reduce the angle of the stationary blade with respect to the axial direction so that the pressure fluctuation detected by the sensor becomes smaller than the stall generation pressure data.
By adjusting the angle of the stationary blade as described above, occurrence of “turning stall” can be suppressed.

  In addition, the conditions for the occurrence of “spinning stall” vary depending on the pressure, temperature, and humidity of the fluid sucked into the flow path from the flow path inlet. However, in the rotating machine configured as described above, the occurrence of “swing stall” is suggested. Since the occurrence of “turning stall” is suppressed based on the pressure fluctuation, it is possible to suppress the occurrence of “turning stall” regardless of the change in the condition for generating “turning stall”.

  Furthermore, according to the rotating machine having the above-described configuration, the “rotation stall” is prevented from being generated based on the pressure fluctuation detected by the pressure sensor at the time of starting or stopping. The power to rotate can be reduced, and the running cost of the rotating machine can be reduced accordingly. Furthermore, it is possible to shorten the time required to start and stop the rotating machine.

  In the rotating machine, it is preferable that the pressure sensor is provided between the moving blade and the stationary blade arranged at intervals in the axial direction.

  In the rotary machine configured as described above, the pressure sensor is not disposed opposite to the tip portion of the rotor blade in the radial direction of the rotor. For this reason, it can suppress that a pressure sensor detects the pressure fluctuation | variation based on the local disturbance of the fluid which arises in the front-end | tip part of a moving blade. Therefore, the pressure of the fluid compressed by the compression stage can be detected with high accuracy. In other words, it is possible to reliably detect a pressure value or pressure fluctuation that suggests the aforementioned “surge” or “turning stall”.

  According to the present invention, it is possible to detect the pressure value that suggests the occurrence of “surge” during the rated operation of the rotary machine by the pressure sensor provided on the rear side of the plurality of compression stages, and output from the pressure sensor. The angle of the stator blades can be adjusted based on the pressure value detected by the pressure sensor so that the pressure value detected by the pressure sensor is less than or equal to the surge generation pressure value. it can.

It is a schematic sectional drawing which shows the rotary machine which concerns on one Embodiment of this invention. FIG. 2 is a schematic view showing a circumferential arrangement of moving blades and stationary blades constituting the same compression stage in the rotary machine of FIG. 1. It is a block diagram which shows the relationship between the pressure sensor, control apparatus, and actuator which comprise the rotary machine of FIG. It is a graph which shows the turning stall limit at the time of starting and a stop of the rotary machine of FIG. It is a graph which shows the pressure distribution of the axial direction of a flow path at the time of the rated operation of a general rotary machine. It is a graph which shows the relationship between the pressure and flow volume in the flow-path exit side at the time of rated operation of a general rotary machine.

Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
A compressor (rotary machine) 1 according to the present embodiment is an axial-flow compressor that compresses a gas (fluid) W by using lift of a moving blade 30 and is installed in, for example, a gas turbine. In addition, when providing the compressor 1 in a gas turbine, in a gas turbine, the compressed gas W and fuel are mixed, the turbine is rotated by the combustion gas which burned, and this is made into the motive power of the compressor 1.
As shown in FIG. 1, the compressor 1 includes a casing 10 that is formed in a cylindrical shape, a rotor 20 that is rotatably provided inside the casing 10, a stationary blade 40 that is attached to the inner periphery of the casing 10, and It has. The rotor 20 includes a rotor main body 21 formed in a columnar shape, and a moving blade 30 attached to the outer peripheral portion of the rotor main body 21.

The rotor body 21 is rotatable around the axis C <b> 1 of the rotor body 21 in the casing 10. The axis of the casing 10 coincides with the axis C1 of the rotor body 21. The rotor main body 21 is connected to a prime mover such as the turbine described above and is rotated by the driving force of the prime mover.
And between the inner peripheral part of the casing 10 and the outer peripheral part of the rotor main body 21, the flow path FP through which the gas W flows in the direction of the axis C1 (the direction from the left side to the right side in FIG. 1) is defined. In FIG. 1, the left end of the casing 10 is an inlet (flow path inlet X0) of the flow path FP that sucks the gas W, and the right end is an outlet (flow path) of the flow path FP that flows the gas W to the outside. Exit X1). The flow path FP is formed so that the cross-sectional area of the flow path FP orthogonal to the direction of the axis C1 gradually decreases as it goes from the flow path inlet X0 side (upstream side) to the flow path outlet X1 side (downstream side). Yes. In the present embodiment, the flow path FP is formed by forming the casing 10 such that the inner diameter dimension of the casing 10 decreases from the upstream side toward the downstream side. However, the present invention is not limited to this. Absent.

The moving blade 30 extends radially outward from the rotor main body 21, and the distal end portion of the moving blade 30 in the extending direction is opposed to the inner peripheral portion of the casing 10 through a radial gap. A plurality of the moving blades 30 are arranged at equal intervals in the circumferential direction of the rotor body 21 to constitute an annular moving blade group (see FIG. 2). In addition, a plurality (five in the illustrated example) of annular blade groups including a plurality of blades 30 are arranged in the direction of the axis C1.
The rotor blade 30 thus arranged moves in the circumferential direction of the rotor body 21 (direction C in FIG. 2) as the rotor body 21 rotates. As a result, the gas W on the upstream side of the moving blade 30 flows and is compressed on the downstream side.

  The stationary blade 40 extends radially inward from the casing 10, and the distal end portion of the stationary blade 40 in the extending direction is opposed to the outer peripheral portion of the rotor body 21 with a gap. A plurality of the stator blades 40 are arranged at equal intervals in the circumferential direction of the casing 10 on the downstream side of each annular rotor blade group to constitute an annular stator blade group (see FIG. 2). Similar to the annular blade group, a plurality (five in the illustrated example) of annular stator blade groups are arranged in the direction of the axis C1. As described above, the moving blade 30 and the stationary blade 40 are provided adjacent to each other in the direction of the axis C1.

As shown in FIGS. 1 and 2, each stationary blade 40 has a radial direction of the casing 10 as a central axis so that the angle of the chord 41 of the stationary blade 40 with respect to the direction of the axis C1 changes within a predetermined range. The casing 10 is swingably attached.
The stator blade 40 (annular stator blade group) provided in this way adjusts the flow direction of the gas W that has passed through the rotor blade 30 (annular rotor blade group) adjacent to the upstream side of the stator blade 40 to the downstream side of the stator blade 40. It plays the role which flows in efficiently with respect to the moving blade 30 which adjoins, or the role which flows out efficiently from the flow-path exit X1.

In the compressor 1 configured as described above, one compression stage 50 that compresses the gas W is configured by one annular moving blade group and an annular stationary blade group that are arranged at intervals in the direction of the axis C1. . A plurality of compression stages 50 are arranged in the direction of the axis C1. The plurality of compression stages 50 include a front stage side located on the flow path inlet X0 side with respect to the intermediate position X2 (see FIG. 1) in the arrangement direction, and a rear stage side located on the flow path outlet X1 side with respect to the intermediate position X2. It is divided into.
Further, in the compressor 1 of the present embodiment, since the number of compression stages 50 is an odd number (five stages in the illustrated example), the compression stages 50A and 50B on the front stage side and the compression stages 50D and 50E on the rear stage side are included. One compression stage 50C (middle compression stage 50C) is located between them. For this reason, the intermediate position X2 in the arrangement direction described above indicates the position between the moving blade 30 and the stationary blade 40 constituting the middle compression stage 50C.

  Although not shown, in the flow path FP of the compressor 1, the rotation direction of the rotor 20 is the same as that of the rotor 20 with respect to the gas W flowing from the flow path inlet X0 upstream of the plurality of compression stages 50 described above. An inlet guide vane that improves the efficiency of the compressor 1 by adding a pre-turn to the direction may be provided.

Furthermore, the compressor 1 includes an angle adjusting mechanism 60 that changes the angle of the stationary blade 40 with respect to the direction of the axis C1.
The angle adjustment mechanism 60 includes a movable cylindrical member 61 formed in a cylindrical shape, a link mechanism 62 that connects the stationary blade and the movable cylindrical member 61, an actuator 63 (see FIG. 3) that drives the movable cylindrical member 61, It has.

The movable cylinder member 61 is arranged so as to cover the casing 10 from the radially outer side, and is movable in the direction of the axis C1. The link mechanism 62 converts the movement of the movable cylinder member 61 in the direction of the axis C <b> 1 into the swing of the stationary blade 40. Further, the actuator 63 drives the movable cylinder member 61 to move in the direction of the axis C1 in accordance with a control signal output from a control device 80 (see FIG. 3) described later.
In the configuration of the present embodiment, all the stationary blades 40 are connected to the same movable cylinder member 61 by the link mechanism 62. Thereby, when the movable cylinder member 61 moves by a predetermined distance in the direction of the axis C1, all the stationary blades 40 swing by the same angle in the same direction. That is, in the configuration of the present embodiment, all the stationary blades 40 swing synchronously.

Moreover, the compressor 1 of this embodiment is provided with the pressure sensor 70 which is provided in the inner peripheral part of the casing 10 and detects the pressure of the flow path FP.
A plurality of pressure sensors 70 are arranged in the direction of the axis C1, and the plurality of pressure sensors 70 are adjacent to the downstream side of the stationary blades 40 arranged in the direction of the axis C1 (the rear edge of the stationary blades 40). In other words, it is arranged at a position adjacent to the downstream side of each compression stage 50. In addition, the pressure sensors 70A to 70D other than the pressure sensor 70E arranged on the most downstream side are between the compression stages 50 and 50 adjacent in the direction of the axis C1, that is, the trailing edge of the stationary blade 40 located on the upstream side. And the leading edge of the moving blade 30 located on the downstream side.

Thereby, a plurality of pressure sensors 70C, 70D, and 70E (rear-stage pressure sensors 70C, 70D, and 70E) are arranged in the direction of the axis C1 on the rear side of the plurality of compression stages 50. A plurality of pressure sensors 70A and 70B (front-stage pressure sensors 70A and 70B) are also arranged in the direction of the axis C1 on the front stage side of the plurality of compression stages 50.
Note that only one pressure sensor 70 may be arranged in the circumferential direction of the casing 10 at the same position in the direction of the axis C1, for example, but a plurality of pressure sensors 70 may be arranged in the circumferential direction, for example.

As shown in FIG. 3, the compressor 1 includes a control device 80 that controls the operation of the actuator 63 of the angle adjustment mechanism 60 based on the pressure values output from the plurality of pressure sensors 70.
The control device 80 has a predetermined pressure value (surge generated pressure value) that indicates the occurrence of “surge” in the compressor 1 and a predetermined pressure fluctuation (shutdown generated pressure data) that indicates the occurrence of “swing stall”. Is stored. The pressure fluctuation is a temporal fluctuation (pressure waveform) of the pressure value, and includes values such as the amplitude and frequency of the pressure waveform. Accordingly, the stall-generated pressure data stored in the memory unit 81 includes values such as a pressure waveform and its amplitude and frequency when the “turning stall” is generated.

These surge generation pressure values and stall generation pressure data are, for example, pressure values and pressure fluctuations measured by performing a test (trial operation) that intentionally generates “surge” or “swing stall” in the compressor 1. For example, it is set to a level lower than the measured pressure value or pressure fluctuation.
In the present embodiment, the surge generation pressure value and the stall generation pressure data stored in the memory unit 81 are a plurality of pressure values and pressure fluctuations measured by the plurality of pressure sensors 70 during the trial operation of the compressor 1. It is set based on the lowest level pressure value and pressure fluctuation.

  Then, the control device 80 detects the pressure sensor 70 (particularly, the rear side pressure sensors 70C, 70D, and 70E) in a state where the rotor 20 of the compressor is rotating at a rated rotational speed (for example, 3600 rpm) (at the time of rated operation). When the detected pressure value is equal to or greater than the surge generation pressure value, the actuator 63 is controlled to compare the angle of the stationary blade 40. Configured to adjust. That is, the control device 80 is configured to adjust the angle of the stationary blade 40 when a sign of “surge” is detected based on the detected pressure value. At this time, the angle adjustment of the stationary blade 40 is performed so that the angle of the stationary blade 40 with respect to the direction of the axis C1 decreases.

  Further, the control device 80 detects the pressure fluctuation detected by the pressure sensor 70 (particularly, the front side pressure sensors 70A and 70B) when the compressor 1 is started or stopped, and the stall generation pressure data stored in the memory unit 81. And the actuator 63 is controlled when the detected pressure fluctuation is equal to or higher than the stall-generated pressure data (for example, the detected pressure fluctuation amplitude is equal to or greater than the stall-generated pressure data amplitude). The angle of the stationary blade 40 is adjusted. In other words, the control device 80 is configured to adjust the angle of the stationary blade 40 when detecting a sign of “turning stall” based on the detected pressure fluctuation. At this time, the angle adjustment of the stationary blade 40 is performed so that the angle of the stationary blade 40 with respect to the direction of the axis C1 decreases.

Next, a method for adjusting the angle of the stationary blade 40 during the rated operation of the compressor 1 having the above configuration will be described.
At the rated operation of the compressor 1, for example, the control device indicates that the pressure value detected by any one of the plurality of pressure sensors 70 (particularly, the rear pressure sensors 70C, 70D, 70E) is equal to or greater than the surge generation pressure value. When 80 is determined, the control device 80 controls the actuator 63 to adjust the angle of the stationary blade 40 (blade chord 41).

The angle adjustment at this time is performed so that the angle of the stationary blade 40 with respect to the direction of the axis C1 decreases. As a result, the flow rate of the gas W flowing in the direction of the axis C1 in the flow path FP increases, so that the pressure value detected by the plurality of pressure sensors 70 decreases. Then, when the control device 80 determines that the detected pressure value is smaller than the surge generation pressure value, the control device 80 may stop the oscillation of the stationary blade 40, that is, the above-described stationary blade 40. What is necessary is just to complete angle adjustment.
The occurrence of “surge” can be prevented by adjusting the angle of the stationary blade 40 as described above.

Next, a method for adjusting the angle of the stationary blade 40 at the time of starting the compressor 1 will be described (see FIG. 4).
In the graph of FIG. 4, the design mounting angle of the stationary blade 40 is used as a reference for the angle of the stationary blade 40 (θ = 0 °). Further, the horizontal axis of the graph shown in FIG. 4 represents a deviation from the design mounting angle (θ = 0 °) of the stationary blade 40. Further, the horizontal axis positive direction (right direction in FIG. 4) of this graph is a direction in which the angle θ of the stationary blade 40 with respect to the axis C1 decreases, that is, a direction in which the flow rate of the gas W passing through the flow path FP increases. It has become.

The design mounting angle of the stationary blade 40 is a state in which the rotational speed R of the rotor 20 is set between 0 (rpm) and idling rotational speed R0 (rpm). The angle is set so as not to place an excessive burden on the rotor blade 30 or the like even if it does not occur. In addition, the chord 41 of the stationary blade 40 set to the design mounting angle is inclined with respect to the axis C1, as shown in FIG.
In addition, the “swing stall generation region” indicated by hatching in the graph of FIG. 4 indicates a region where “swing stall” occurs due to the relationship between the angle θ of the stationary blade 40 and the rotation speed R of the rotor 20. Then, the position of the boundary line 1 of the “spinning stall generation region” changes depending on atmospheric conditions such as pressure, temperature, and humidity of the atmosphere (the gas W upstream of the flow path inlet X0 of the compressor 1). .

  Then, at the time of starting the compressor 1 that increases the rotational speed R of the rotor 20 from the state in which the rotation of the rotor 20 is completely stopped to the rated rotational speed R1 (rpm) (see FIG. 4), first, “swing stall” The rotation speed R of the rotor 20 is gradually increased from 0 (rpm) to the idling rotation speed R0 (rpm) so as not to occur. At this time, the angle θ of the stationary blade 40 is kept at the design mounting angle.

  After the rotational speed R of the rotor 20 reaches the idling rotational speed R0, the rotational speed R of the rotor 20 is increased from the idling rotational speed R0 to the rated rotational speed R1. As described above, when the rotational speed R of the rotor 20 is increased, the axis line is set so that the flow rate of the gas W flowing through the flow path FP is not increased unnecessarily, that is, the power for rotating the rotor 20 is not increased unnecessarily. The angle θ of the stationary blade 40 (blade 41) with respect to the C1 direction is increased from the mounting design angle (θ = 0 °) to the angle during rated operation (for example, θ = −θ1, −θ2). The angle adjustment of the stationary blade 40 is performed by the control device 80.

  Furthermore, in the compressor 1 of the present embodiment, while increasing from the idling rotational speed R0 to the rated rotational speed R1, pressure fluctuations are detected by the plurality of pressure sensors 70 (particularly, the front-side pressure sensors 70A and 70B), and a plurality of pressure sensors 70 are detected. When the control device 80 determines that the pressure fluctuation detected by any one of the pressure sensors 70 is equal to or higher than the stall generation pressure data, the control device 80 controls the actuator 63. Then, the angle θ of the stationary blade 40 (the chord 41) is adjusted.

The angle adjustment at this time is performed so that the angle θ of the stationary blade 40 with respect to the direction of the axis C1 decreases. As a result, the flow rate of the gas W flowing in the direction of the axis C1 in the flow path FP increases, so that the level of pressure fluctuation detected by the plurality of pressure sensors 70 decreases. Then, when the control device 80 determines that the detected pressure fluctuation is smaller than the level of the stall generation pressure data, the control device 80 stops the oscillation of the stationary blade 40 or the angle θ of the stationary blade 40. What is necessary is just to rock | fluctuate the stationary blade 40 in the direction which increases.
By adjusting the angle of the stationary blade 40 as described above, it is possible to prevent the “turning stall” from occurring. In other words, it is possible to prevent the relationship between the angle θ of the stationary blade 40 and the rotation speed R of the rotor 20 from entering the “turning stall region” shown in FIG.
The above-described adjustment of the angle θ of the stationary blade 40 at the time of starting is performed in the same manner when the compressor 1 is stopped.

As described above, according to the compressor 1 of the present embodiment, during the rated operation, the pressure indicating “surge” is detected by the plurality of pressure sensors 70 (particularly, the rear stage side pressure sensors 70C, 70D, and 70E). can do. In particular, since the pressure indicating “surge” can be detected at a plurality of locations in the direction of the axis C1 of the plurality of compression stages 50, the length of the flow path FP in the direction of the axis C1 (particularly the length on the rear stage side) is long. However, the pressure suggesting the occurrence of “surge” can be easily detected, and the reliability can be further improved.
Further, based on the pressure values output from the pressure sensors 70, the angle θ of the stationary blade 40 is adjusted so that the pressure value detected by the pressure sensor 70 is equal to or less than the surge generation pressure value. It is possible to prevent the occurrence of “surge” during rated operation.

Moreover, according to the compressor 1 of this embodiment, the pressure fluctuation which suggests "rotation stall" is detected by the several pressure sensor 70 (especially front side pressure sensor 70A, 70B) at the time of starting or stopping. In addition, based on the pressure fluctuations output from the pressure sensors 70, the angle θ of the stationary blade 40 is adjusted so that the pressure fluctuations detected by the pressure sensors 70 are equal to or lower than the stall generation pressure data. It is possible to prevent the “turning stall” from occurring at the time of starting or stopping of 1.
Furthermore, as described in the description of the boundary line 1 shown in FIG. 4, the generation conditions of the “turning stall” are the pressure, temperature, and humidity (atmospheric conditions) of the gas W sucked into the flow path FP from the flow path inlet X0. However, in this embodiment, since the “turning stall” is prevented based on the pressure fluctuation that suggests the occurrence of “turning stall”, the “turning” It is possible to prevent the occurrence of “stall”.

  Further, in the compressor 1 according to the present embodiment, the pressure sensor 70 disposed between the stationary blades 40 adjacent to each other in the direction of the axis C1 is moved on the downstream side and the trailing edge of the stationary blade 40 located on the upstream side. It is located between the leading edges of the blades 30, that is, does not oppose the rotor 20 in the radial direction with respect to the tip of the blade 30. For this reason, it can suppress that the pressure sensor 70 detects the pressure fluctuation based on the disturbance of the local gas W produced in the front-end | tip part of the moving blade 30. FIG. Therefore, the pressure of the gas W compressed by the compression stage 50 can be detected with high accuracy. In other words, it is possible to reliably detect a pressure value or pressure fluctuation that suggests the aforementioned “surge” or “turning stall”.

  Further, according to the compressor 1 of the present embodiment, the “turning stall” is prevented from being generated based on the pressure fluctuation detected by the pressure sensor 70 at the time of starting or stopping. Therefore, the power for rotating the rotor 20 can be reduced, and the running cost of the compressor 1 can be reduced accordingly. Furthermore, it is possible to shorten the time required to start and stop the compressor 1.

Hereinafter, the two effects obtained when the compressor 1 is started or stopped will be described in detail with reference to the graph shown in FIG.
In the compressor 1 of the present embodiment, as described above, since the “turning stall” is prevented from being generated based on the pressure fluctuation detected by the pressure sensor 70, the compressor 1 shown in FIG. As described above, the angle θ of the stationary blade 40 is increased in correspondence with the rotational speed R of the rotor 20 so that the relationship between the rotational speed R of the rotor 20 and the angle θ of the stationary blade 40 does not enter the “spinning stall generation region”. Alternatively, there is no need to preset the angle change schedule S1 to be decreased.
In other words, regardless of the magnitude of the change in the rotational speed R of the rotor 20 (increase or decrease in the rotational speed R per unit time), the angle θ of the stationary blade 40 changes greatly in a short time (increases during startup, and during stoppage). Decrease).

More specifically, for example, when the compressor 1 is started, the angle θ of the stationary blade 40 approaches the boundary line l from the mounting design angle as in the angle change schedule S2 illustrated in the graph of FIG. Since the occurrence of the “turning stall” is prevented as described above even if the angle is changed (even if the movement from the point E to the point F in the angle change schedule S2 is performed), the “turning stall generation region” is entered. There is nothing.
Since the angle adjustment of the stationary blade 40 is performed based on the pressure fluctuation detected by the pressure sensor 70, the angle θ of the stationary blade 40 is increased along the boundary line 1 in a region near the boundary line l. be able to. That is, it is possible to move from the point F to the point G in the angle change schedule S2.

As described above, when the compressor 1 is started or stopped, the angle θ of the stationary blade 40 can be changed in a region close to the boundary line l, so that the rotor 20 can be compared with the angle change schedule S1. The power for rotating can be reduced. As is clear from the graph of FIG. 4, the angle θ of the stationary blade 40 can be changed to a position close to the boundary line 1 even during rated operation (rated rotational speed R1). Can be greatly changed, that is, a wide operating range can be secured.
Further, at the time of starting or stopping, the angle θ of the stationary blade 40 can be greatly changed in a short time, so that the time required for starting and stopping the compressor 1 can be shortened.

Although the details of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.
For example, in the memory unit 81, only the lowest level surge generation pressure value and stall generation pressure data are stored. However, for example, surge generation pressure values and stall generation pressure data for each of the plurality of pressure sensors 70 are stored. May be. In this case, the control device 80 compares the pressure value and the pressure fluctuation detected by the one pressure sensor 70 with the surge generation pressure value and the stall generation pressure data corresponding to the one pressure sensor 70, so that the above-described embodiment. Similarly to the above, it may be determined whether or not the angle adjustment of the stationary blade 40 is necessary.

Further, the pressure sensors 70A to 70D other than the pressure sensor 70E arranged on the most downstream side are not limited to the positions shown in the above embodiment, but at least the stationary blades 40 adjacent in the direction of the axis C1. What is necessary is just to be arranged in between.
Therefore, the pressure sensors 70 </ b> A to 70 </ b> D may be disposed, for example, between the trailing edge of the moving blade 30 located on the upstream side and the leading edge of the stationary blade 40 located on the downstream side. In addition, the magnitude of the pressure fluctuation based on the local disturbance of the gas W generated between the tip of the rotor blade 30 and the inner peripheral portion of the casing 10 as the rotor 20 rotates causes the occurrence of “surge”. In a case where the pressure sensor 70 is sufficiently small compared with the suggested pressure or the magnitude of the pressure fluctuation that suggests the occurrence of the “turning stall”, the pressure sensor 70 faces, for example, the tip of the moving blade 30 in the inner peripheral portion of the casing 10. It may be arranged in a position.

  As described above, when the pressure sensors 70 </ b> A to 70 </ b> D are arranged between the trailing edge of the moving blade 30 and the leading edge of the stationary blade 40, one pressure sensor 70 is an intermediate position X <b> 2 of the plurality of compression stages 50. Will be placed. In this case, the pressure sensor 70 disposed at the intermediate position X2 may function as a rear-stage pressure sensor that detects a pressure that indicates “surge”, or a front-stage pressure sensor that indicates the occurrence of “swing stall”. May function as Moreover, you may make it function as both these sensors.

In the above embodiment, a plurality of pressure sensors 70 are arranged in the direction of the axis C1 on the front side or the rear side of the plurality of compression stages 50. For example, only one pressure sensor 70 is arranged. But you can.
Furthermore, in the above embodiment, the pressure sensors 70 are arranged on both the front and rear sides of the plurality of compression stages 50. However, if the compressor of the present invention can detect at least only the pressure suggesting "surge". Therefore, it is only necessary to be disposed at least on the rear side of the plurality of compression stages 50.

The angle adjusting mechanism 60 is not limited to the movable cylinder member 61, the link mechanism 62, and the actuator 63, and may be any configuration that is controlled by the control device 80 so that at least the angle of the stationary blade 40 changes. Good.
Furthermore, the angle adjusting mechanism 60 is not limited to being configured to synchronously swing all the stationary blades 40, and for example, to synchronously swing only the stationary blades 40 that constitute the same annular stationary blade group, The plurality of annular stator blade groups may be configured to swing independently of each other. Further, for example, the movable cylinder member 61 and the link mechanism 62 may not be provided, and all the stationary blades 40 may be configured to swing independently by individual actuators.

  Thus, the plurality of stationary blades 40 swing independently of each other, and as described above, a plurality of surge generation pressure values and stall generation pressure data are stored in the memory unit 81 in association with the plurality of pressure sensors 70. In this case, for example, when the pressure value or pressure fluctuation detected by one pressure sensor 70 reaches a level higher than the surge generation pressure value or stall generation pressure data corresponding to the one pressure sensor 70, the control device 80 In addition, only the angle of the stationary blade 40 (one annular stationary blade group) corresponding to one pressure sensor 70 may be adjusted.

Moreover, in the compressor 1 of the said embodiment, although the stage number of the compression stage 50 is set to the odd number, you may set to an even number, for example. In this case, there is no middle compression stage 50C as in the above embodiment, and the position between the compression stage 50 on the front stage side and the compression stage 50 on the rear stage side is in the arrangement direction of the plurality of compression stages 50. Intermediate position.
Further, in the above embodiment, the present invention is applied to the axial flow type compressor 1, but the mixed flow type compressor, the compressor combining the axial flow type and the mixed flow type, the axial flow type or the mixed flow type. The present invention can also be applied to other blowers.

DESCRIPTION OF SYMBOLS 1 ... Compressor (rotary machine), 10 ... Casing, 20 ... Rotor, 30 ... Moving blade, 40 ... Stator blade, 50, 50A, 50B, 50C, 50D, 50E ... Compression stage, 60 ... Angle adjustment mechanism, 70, 70A, 70B, 70C, 70D, 70E ... pressure sensor, 80 ... control device, C1 ... axis, FP ... channel, W ... gas (fluid), X0 ... channel inlet, X1 ... channel outlet, X2 ... intermediate position

Claims (4)

A rotary machine configured by arranging a plurality of compression stages composed of moving blades and stationary blades provided in a flow path so as to be adjacent to each other in the axial direction of the rotor, in the axial direction,
An angle adjusting mechanism for changing an angle of the stationary blade with respect to the axial direction;
A pressure sensor for detecting the pressure of the flow path;
A control device for controlling the angle adjustment mechanism based on a pressure value output from the pressure sensor,
The plurality of compression stages are divided into a front stage located on the upstream side of the flow path and a rear stage side located on the downstream side of the flow path,
The rotary machine, wherein the pressure sensor is arranged at least on the rear stage side.   The rotating machine according to claim 1, wherein a plurality of the pressure sensors arranged on the rear stage side are arranged in the axial direction.   The rotary machine according to claim 1, wherein the pressure sensor is arranged on the front stage side.   4. The pressure sensor according to claim 1, wherein the pressure sensor is provided between the moving blade and the stationary blade arranged at intervals in the axial direction. 5. Rotating machine.

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