WO2019052734A1

WO2019052734A1 - Method for detecting a misalignment of the angular position of a compressor guide vane arranged in a compressor and which can swivel about the longitudinal axis thereof

Info

Publication number: WO2019052734A1
Application number: PCT/EP2018/070387
Authority: WO
Inventors: Stephan Klumpp; Ulrich Waltke
Original assignee: Siemens Aktiengesellschaft
Priority date: 2017-09-14
Filing date: 2018-07-27
Publication date: 2019-03-21
Also published as: DE102017216279A1

Abstract

The invention relates to a method for detecting a misalignment of the angular position of a compressor guide vane (19) arranged in a compressor (5) and which can swivel about the longitudinal axis (23) thereof, wherein the compressor (5) is part of a gas turbine (1), which additionally comprises a combustion chamber (6), wherein a compressor outlet temperature (T) is measured via a plurality of temperature sensors (33) arranged in the region between a compressor outlet (29) and a combustion chamber inlet (31), wherein, considered in the circumferential direction, the temperature sensors (33) have different positions and each temperature sensor (33) supplies a measurement signal (M1, M2, M3, M4), when a sudden, step-like change (S) of at least one measurement signal (M3) is detected, while at least one other measurement signal (M1, M2, M4) remains unchanged, a misalignment is detected. By means of the method according to the invention, it is possible to detect a misalignment of the angular position of a compressor guide vane (19) during operation of the compressor (5) without additional design effort.

Description

description

Method for detecting a misalignment of the angular position of a compressor guide vane arranged in a compressor and pivotable about its longitudinal axis

The present invention relates to a method for Erfas ^¬ sung a malposition of the angular position of a arranged in a compressor, pivotable about its longitudinal axis

Compressor stator. The invention further relates to a system for detecting a malposition of the angular position of a compressor arranged in a compressor, pivotable about its longitudinal axis Verdichterleitschaufel.

It is known that in the assembly of adjustable about its longitudinal axis ^¬ compressor guide vanes and the associated adjustment drive these are individually aligned renznut means of a pre ^¬ direction to a guide vane arranged on the refer-. This is necessary so that al ^¬ le blades of the Verdichterleitschaufelrings always have identical staggering angles in order to ensure a synchronous flow of the following Verdichterlaufschau ^¬ blades during operation. An asynchronous flow of the compressor blades could result in vibratory excitation of individual blades of the blades. In the worst case, this could have a damaging effect on the running ^blades . The angular position of the guide vanes is known to measure by means of a Universal protractor and an auxiliary device of au ^¬ SEN on the housing of the compressor. The Hilfsvorrich ^¬ tion, which was applied to the reference groove on the guide vane, serves as a stop for the one measuring leg of the angle blade. The rear side surface of an adjusting lever arranged on the ver ^¬ rotatable compressor guide blade serves as a stop surface for the second measuring leg of the protractor on which then the angular position of the guide vane could be read. Due to the cramped space conditions on the compressor and depending on the position of the compressor vane to be checked on the circumference can lead to Ablese ^¬ errors and not exactly applied measuring legs. This may be the case in particular when the fitter has to work overhead. By faulty control, it can not be detected be ^¬ mög Lich that correctly adjusted blades unnecessarily adjusted into an incorrect position or incorrect Stel ^¬ ments of compressor. Overall, this can thus lead to partially unevenly set staggering angles of the blades of rotatable vanes over the circumference. Another source of error which may result in a slightly asymmetrical position of the compressor vanes ^¬ A, the tolerances through the use of the auxiliary device are.

It is also possible that the connection of individual compressor guide vanes to the adjusting device dissolves during operation. As a result, the position of this compressor guide vane is no longer controlled and may differ significantly from the position of the remaining compressor guide vanes in the corresponding row.

The angular position can also be detected by means of a transportable, but expansive laser measuring device, as suggested, for example, by EP 1 895 267 A1. Although the known measuring device works contactlessly with respect to the measuring surface, in the cramped environment this is only possible with the use of a deflecting mirror, which in the harsh industrial environment of such machines is not sufficiently robust and thus susceptible to damage. Consequently, the laser measuring device requires a comparatively gentle handling in order not to impair the availability of the measuring device.

Further, from US 4,597,187 A a the constructive features of the preamble of claim 1 corresponding

Measuring device for measuring the angle of attack of rigid compressor blades known. This is mounted on a table to a pre-assembled, but not yet assembled Measure ring with blades of the compressor. The measuring device comprises a first contact point, which is applied to the leading edge or trailing edge of the blade to be examined. A rotatable cam disc with a measuring arm is then to be pivoted so that two further, arranged on the measuring arm contact points on the airfoil on the suction side or pressure side. The swivel angle of the cam disk is then detected by means of a sensor, which then indicates the angle of attack of the relevant airfoil. The disadvantage here is that the measurement of Anstell ^¬ angle takes place directly on the blade. This requires access of a person to the airfoil. The known device is thus not suitable for determining the angular position ^¬ a arranged in a compressor about its longitudinal axis pivotable compressor guide from the outside.

However, the methods described in the above-mentioned prior art do not allow the detection of an operating -. B. by damage to the mechanical fasteners of Versteilvorrichtung - resulting misalignment of individual vanes within a row of vanes. Object of the present invention is therefore to detect a malposition of the angular position of a compressor vane without additional design effort in the operation of the compressor.

The object is achieved by a method for detecting a malposition of the angular position of a arranged in a compressor, pivotable about its longitudinal axis Verdichterleitschaufel, wherein the compressor is part of a gas turbine, which further comprises a combustion chamber, in which:

a compressor outlet temperature over several, in the area between a compressor outlet and a

Combustion chamber inlet disposed temperature sensors will measure ^¬ ge, wherein the temperature sensors in the circumferential direction viewed different positions aufwei ^¬ sen and each temperature sensor provides a measurement signal,

- when an abrupt step-like change of at least ^¬ is detected in a measurement signal, while zumin- at least one other measurement signal remains unchanged, a malposition is detected.

The object is further achieved according to the invention by a system for detecting a malposition of the angular position of a compressor disposed in a compressor, about its longitudinal axis pivotable Verdichterleitschaufel, wherein the compressor is part of a gas turbine, which further comprises a combustion chamber, comprising ^¬ send:

a plurality of temperature sensors arranged in the region between a compressor outlet and a combustion chamber inlet for measuring a compressor outlet temperature, wherein the temperature sensors have different positions in the circumferential direction, and each temperature sensor supplies a measuring signal,

- And an evaluation unit, which is adapted to evaluate the measurement signals and in a sudden gradarti ^¬ gen change of at least one measurement signal, while ^{¬ at} least one other measurement signal remains unchanged, to detect a faulty position.

The advantages and preferred embodiments set out below with respect to the method can be applied analogously to the system.

The invention is based on the idea of using the measurement signals of the temperature sensors already present for measuring the compressor outlet temperature in order to detect misalignments of the angular position of adjustable guide vanes of the compressor. Such temperature sensors are usually in immersion sleeves or in removable probes built-in thermocouples in the flow channel of the compressor outlet diffuser or in a position between the

Compressor outlet diffuser and the burner inlet are introduced into the flow. For this, a ent ^¬ speaking evaluation or interpretation of the measured signals is required. For gas turbines, the compressor discharge temperature is measured by default during operation. This is done by several measuring points that are distributed in the area of the compressor outlet. Such a measurement of the compressor outlet temperature with regard to stable operation on hot days is provided, for example, in WO 2015/121035 A1. The measured compressor outlet temperature is compared with a desired compressor outlet temperature and in the event of a deviation, the compressor temperature of the flow medium at the compressor inlet or in the compressor is changed using a cooling device.

The measuring signals of all temperature sensors are in normal operation at about the same course, only minimal differences UN of not more than 4 K are between the Messsig ^¬ tional usual. However, there is a guide vane of a vane row of the compressor adjustable ^¬ cash different from the rest of the routing shovel ^¬, this affects the local temperature downstream structure. The measuring signal of the closest temperature sensor detects a sudden increase in temperature or a sudden drop in temperature, the temperature change being maintained over time. Thus, an excessively ^¬ least one of the measurement signals a stepped profile with a single stage. The level in the course is immediately visible. It can therefore be generated after a few seconds a warning. The further from the compressor vane in the Fehlstel ^¬ ment temperature sensors will display a smaller level in the course of the measurement signal or no change (that is, still a steady measurement signal).

A sudden step-like change here means an unexpected change in the measuring signal, which deviates from a desired value and / or represents a deviation from the remaining measuring signals.

A misalignment of the angular position of a compressor guide vane can thus be achieved by continuously monitoring the compressor outlet temperature and, in particular, the b

Detect differences between the individual measurement signals. The monitoring is carried out in particular automatically. As a result, a warning can be generated at an early stage and damage can be prevented by, in particular, bringing the gas turbine down and the angular position of all the swiveling ones

Compressor vanes are checked and corrected if necessary.

For the correct interpretation of the measurement signals, it is also important to check whether the measurement signal of at least one of the other temperature sensors remains unchanged. In this way, evaluation reliability can be increased and the risk of misinterpretation of the measurement minimized. If at least one of the temperature sensors (usually the one closest to the displaced compressor vane) provides a measurement signal having an unexpected stage profile and at the same time at least one other temperature sensor (usually the farthest from the displaced compressor vane) does not significantly change the temperature Having course of the measurement signal, the measurement signals indicate a malposition of the angular position of one of the pivotable compressor guide vanes.

According to a further preferred embodiment, the misalignment is detected when the step-like change of the at least one measurement signal exceeds a predetermined threshold, in particular a threshold value of 2 K exceeds ^¬ . Changes in the measuring signal of +/- 2 K are classified as fluctuations within a permissible tolerance range. This is interpreted as a vane misalignment and, if necessary, a message is issued only if the temperature increase continues or if the temperature drop continues to exceed 2 K.

With regard to a particularly reliable measurement, at least three temperature sensors are preferably used for measuring the compressor outlet temperature, since the use of only one or two temperature sensors is not sufficient for a qualitatively evaluable result. Conceivable is the set of four, five or more temperature sensors, however, in practice, the number of temperature sensors used is limited by the available space. Preferably, the compressor outlet temperature is measured continuously, in particular is measured at a distance of a few seconds, in particular one time per second. It can thus be determined directly a deviation of the temperature profile.

Advantageously, the temperature sensors are unevenly distributed in the circumferential direction, i. it is not always the same distance or not always the same angle between each two adjacent temperature sensors. In this way, the spatial conditions and the available space for attaching the temperature sensors are optimally used.

Conveniently, the temperature sensors are distributed around the circumference of a downstream of the compressor diffuser. Due to its close proximity to the compressor and its annular design, the diffuser is ideal for placing the temperature sensors around its circumference. According to a preferred embodiment variant is based on the

Position of the at least one temperature sensor whose measuring ^¬ signal has the step-like change, a sector be ^¬ true, in which the ^{Verdichterleitschaufel} is in the wrong ^¬ position. If the measurement signal from one of the temperature sensors has a spread or jump and the circumferential position of the temperature sensor is known, the circumferential position of the displaced guide blade can be limited to the area between the said temperature sensor and the two adjacent sensors. If one of the adjacent temperature sensors shows similar abnormalities in the measurement signal, the vane can be expected in the circumferential direction between these two temperature sensors. An embodiment of the invention will be described with reference to a

Drawing explained in more detail. Herein show:

1 shows a gas turbine in a longitudinal partial section, comprising temperature sensors for detecting a

Compressor outlet temperature, and

FIG 2 shows the course of the temperature T over the time t gemes ^¬ sen by the temperature sensors according to FIG 1. The same reference numerals have the same meaning in the various figures.

1 shows a gas turbine 1 in a longitudinal partial section. The gas turbine 1 has inside a rotatably mounted about a machine axis 2 rotor 3. Along the rotor 3 follow one another an intake housing 4, a compressor 5, an annular combustion chamber 6 with a plurality of rotationally symmetrical mutually arranged burners 7, an expansion turbine 8 and an exhaust housing 9. The annular combustion chamber 6 forms a combustion chamber 17, which communicates with an annular hot gas channel 18 , There, for four successive Turbi ^¬ nenstufen 10, the expansion turbine 8. Each turbine stage 10 is formed from two blade or vane rings. GeSe hen in the flow direction of a hot gas generated in the annular combustion chamber 6 11, followed in the hot gas channel 18 each having a row of guide vanes 13 a row formed from rotor blades 15 14. The managing ^¬ blades 12 are mounted on the stator, whereas the rotor blades 15 of a row 14 by means of a turbine disk are attached to the rotor 3. On the rotor 3, a generator or a working machine (not shown) is coupled.

At the suction-side housing entrance of the compressor 5 adjustable compressor guide vanes 19 are provided. The compressor guide vanes 19 are arranged in the annular flow channel of the compressor 5 and can be rotated by a Antriebsvor ^¬ direction 21 about its respective longitudinal axis 23, for example, to set the gas turbine 1 flowing through Mas ^¬ senstrom. Depending on the angle of attack, a special ders large or small mass flow to flow through the gas turbine 1 as needed. In order to reduce flow losses in the direction ^¬ intake ambient air and a vibration ^¬ stimulus from immediately downstream of the Verdichterleit- blades 19 rotating blades 20 to prevent, which takes place at a seen over the circumference uneven flow against the blades 20, all Verdichterleit be shovel ^¬ 19 synchronously adjusted with constant retention of the same angle by means of the drive device 21.

The compressor 5 includes a compressor outlet 29 to which a diffuser is connected downstream of 25, delayed in which the flow and kinetic flow energy into pressure is umgewan ^¬ punched. The diffuser 25 opens into a plenum 27. In the area between the compressor outlet 29 and a combustion chamber inlet 31, ie in the region of the diffuser 25 or the plenum 27, a plurality of temperature sensors 33 are provided for measuring the compressor outlet temperature. In the embodiment shown, a temperature sensor 33 is shown symbolically, however, four temperature sensors 33 are arranged around the circumference of the diffuser 25, wherein they all have the same axial position and differ only by their position in the circumferential direction. A uniform distribution around the circumference of the diffuser 25 is not mandatory and not provided. The tempera ^¬ tursensoren 33 communicate with an evaluation unit 35, which evaluates the measurement signals Mi to M ₄ and diener out are for a loading, in particular in the form of a graphical representation of the course of the measurement signals Mi to M. ₄

Each temperature sensor 33 supplies a measurement signal Mi to M ₄ for the temperature profile of the compressed air after the compressor. In the example according to FIG. 1, four temperature sensors 33 are provided whose measurement signals Mi to M ₄ for the temperature T are shown over the time t in FIG. The single ^¬ NEN measurement signals Mi to M ₄ follow substantially the same course and differed only in minimal amount of ge ^¬ measured temperature T. The temperature measurement at Compressor outlet 31 takes place continuously, in particular, each temperature sensor 33 outputs about one measurement per second ei ^¬ NEN measurement. As can be seen from FIG. 2, one of the measurement signals M _{3 has} a jump in the course from time to, the ^further three temperature sensors 33 not detecting such a temperature jump. After the time to the measurement signal M ₃ remains at the higher temperature level, so that there is a gradual change S, wherein the level S is a height ΔΤ> 2 K.

Since the measurement signals Mi, M2 and _M4 of the three further temperature ^¬ sensors 33 also Lie a steady temperature profile remotely and also the step S exceeds a predetermined threshold value of 2 K, the measurement results indicate that only in one sector after the compressor a temperature deviation takes place. This is considered a misalignment of the angular position of at least one of the pivotable

Verdichterleitschaufeln 19 interpreted and a message is issued. The interpretation of the measurement results as well as the message can be done manually as well as automatically. With regard to a high degree of automation and increased security, it is provided, in particular, that the interpretation of the measurement signals Mi to M ₄ takes place via the evaluation unit 35, which also generates the message.

If the operator of the gas turbine 1 would like to obtain information about the position of the guide blade 19 in the misalignment, these can likewise be obtained via the measurement signals Mi to M _{4 of} the temperature sensors, because the displaced compressor guide blade 19 is generally approximately in the circumferential direction in a sector can be determined from the sector of the temperature sensor 33, which supplies the step-like ge measurement signal M3, and the mean change in circumferential position of a power line from the Verdichterleitschau ^¬ felreihe 13 to the plane of the measuring point 33rd By the method described above, it is possible to detect a malposition of the angular position of a ^{Verdichterleit ¬} blade 19 without additional design effort in the operation of the compressor 5.

Claims

claims

A method for detecting a malposition of the angular position of a in a compressor (5) arranged to their

A longitudinal axis (23) pivotable compressor guide vane (19), wherein the compressor (5) is part of a gas turbine (1), which also comprises a combustion chamber (6), in which:

- a compressor discharge temperature (T) over a plurality, in the region between a compressor outlet (29) and ei ^¬ nem combustion chamber inlet (31) arranged Temperatursen ^¬ sensors (33) is measured, wherein the temperature sensors (33) in the circumferential direction, are different Po ^¬ sitions have and each temperature sensor (33) delivers a measurement signal (M _lr M ₂ , M ₃ , M ₄ ),

- If a sudden step-like change (S) of at least one measurement signal (M3) is detected while at least one other measurement signal (Mi, M ₂ , M ₄ ) remains unverän ^¬ changed, a malposition is detected.

2. The method according to claim 1,

wherein the misalignment is detected when the step-like change (S) exceeds a predetermined threshold, in particular exceeds a threshold value of 2 K.

3. The method according to any one of the preceding claims, wherein at least three temperature sensors (33) are used for measuring the compressor outlet temperature (T).

4. The method according to any one of the preceding claims, wherein the compressor ^outlet temperature (T) is measured continuously, in particular, is measured at a distance of a few seconds ^¬ customer, in particular one time per second.

5. The method according to any one of the preceding claims, wherein the temperature sensors (33) viewed in the circumferential direction are distributed unevenly.

6. The method according to any one of the preceding claims, wherein the temperature sensors (33) are distributed around the circumference of the compressor (5) downstream of the diffuser (25).

7. The method according to any one of the preceding claims, wherein based on the position of the at least one temperature sensor (33) whose measurement signal (M3), the step-like Variegated ^¬ tion, a sector is determined in which the Verdichterleitschaufel (19) is in the misalignment ,

8. A system (33, 35) for detecting a malposition of the angular position of a compressor (5) arranged about its longitudinal axis (23) pivotable Verdichterleitschaufel (19), wherein the compressor (5) is part of a gas turbine (1) also comprising a combustion chamber (6), comprising:

- Several, in the region between a compressor outlet (29) and a combustion chamber inlet (31) arranged Temperatursen ^¬ sensors (33) for measuring a compressor outlet temperature (T), wherein the temperature sensors (33) in the circumferential direction have considered different positions, and each

Temperature sensor (33) provides a measurement signal (Mi, M ₂ , M ₃ , M ₄ ),

- And an evaluation unit (35) which is adapted to evaluate the measurement signals (Mi, M ₂ , M ₃ , M ₄ ) and at a sudden step-like change (S) of at least one measurement signal (M3), while at least one other measurement signal

(Mi, M ₂ , M ₄ ) remains unchanged, a malposition to erken ^¬ NEN.

9. System (33, 35) according to claim 8,

wherein the evaluation unit (35) is designed for, the

Detect malposition when the step-like change (S) exceeds a predetermined threshold, ^{insbesonde ¬} re exceeds a threshold value of 2 K.

10. System (33, 35) according to any one of claims 8 or 9, comprising at least three temperature sensors (33) for measuring the compressor outlet temperature.

11. System (33, 35) according to any one of claims 8 to 10, wherein the temperature sensors (33) are adapted to continuously measure the compressor outlet temperature (T), in particular at a distance of a few seconds, in particular once per second.

12. System (33, 35) according to any one of claims 8 to 11, wherein the temperature sensors (33) are arranged unevenly in the circumferential direction.

13. System (33, 35) according to any one of claims 8 to 12, wherein the temperature sensors (33) around the circumference of the compressor (5) downstream of the diffuser (35) are arranged.

14. System (33, 35) according to one of claims 8 to 13, wherein based on the position of the at least one temperature sensor (33) whose measurement signal (M3) the step-like change (S), the evaluation unit (35) determines a sector, in which the compressor guide vane (19) is in the ^{default position} .