EP2999857A1

EP2999857A1 - Method for operating a turbo-machine, wherein an efficiency characteristic value of a stage is determined, and turbo-machine having a device for carrying out the method

Info

Publication number: EP2999857A1
Application number: EP14771526.2A
Authority: EP
Inventors: Hans-Gerd Brummel; Dirk Grieshaber; Uwe Pfeifer; Huub DE BRUYN
Original assignee: Siemens AG
Current assignee: Siemens Energy BV
Priority date: 2013-09-30
Filing date: 2014-09-05
Publication date: 2016-03-30
Also published as: WO2015043916A1; KR20160045868A; KR101833865B1; US10018070B2; US20160138418A1

Abstract

The invention relates to a turbo-machine, which can be operated in an optimized driving range. To this end, a method for operating a turbo-machine having at least one turbo-machine stage, which has at least one rotary shaft is disclosed. According to the method, the following method steps are carried out: a) determining a desired efficiency characteristic value ηsoll of the turbo-machine stage; b) determining an actual efficiency characteristic value ηist of the turbo-machine-stage; c) determining a comparison efficiency characteristic value of the turbo-machine stage by comparing the actual efficiency characteristic value ηist and the desired efficiency characteristic value ηsoll to one another; and d) changing at least one operating parameter of the turbo-machine stage subject to the comparison efficiency characteristic value ηvgl, wherein in order to determine the actual efficiency characteristic value ηist, a measuring of a torque of the rotary shaft of the turbo-machine-stage is carried out. The torque applied to the rotary shaft during the operation of the turbo-machine is measured. Preferably, the torque is measured in a magneto-elastic manner. The invention further relates to a turbo-machine comprising at least one turbo-machine stage, which is has at least one rotary shaft, wherein the turbo-machine has a device for carrying out the method. The turbo-machine is a turbo compressor, for example, which comprises a plurality of compressor stages (turbo-machine stages). Each of the compressor stages can be controlled separately.

Description

description

METHOD FOR OPERATING A FLOW MACHINE IN WHICH

EFFECTIVENESS VALUE OF ONE STAGE IS DETERMINED,

AND FLOW MACHINE WITH A DEVICE FOR IMPLEMENTING THE PROCESS

The invention relates to a method for operating a turbomachine having at least one turbomachine stage, which has at least one rotary shaft, and a turbomachine with a device for carrying out the method.

The turbomachine is, for example, a turbocompressor (turbo compressor) or a hydroturbine. At a

Turbomachine transfers energy through a flowing fluid (gas or liquid). The energy transfer takes place via an impeller with a rotary shaft. On the rotary shaft (drive or driven shaft) are

Rotor blades, vanes or blades arranged, which are shaped so that in the fluid flow (volume flow) results in a pressure difference (Δρ) between the front and back of the impeller.

The power or the power consumption or the

Power output of the turbomachine (or individual

Turbomachine levels) are determined via several measured process parameters (operating parameters). There are problems in measuring accuracy of instruments used to measure the process parameters and the often lack of knowledge of a gas composition or the lack of knowledge of other operating parameters. In many cases, it must be measured over a longer period of time at constant load. As a result, the turbomachine very often can not be driven in the optimum efficiency range. Object of the present invention is to show how a turbomachine can be operated flexibly in an optimal operating range.

To achieve the object, a method for operating a turbomachine with at least one turbomachine stage is specified, the at least one rotation shaft

having. According to the method, the following

Process steps performed:

a) determining a target efficiency characteristic η ₃₀ ιι the

Turbomachinery level,

b) determining an actual efficiency value r | i _St the

Turbomachinery level,

c) determining a comparative efficiency characteristic value of the turbomachine stage by comparing the actual efficiency parameter r | i _St and the target efficiency characteristic value η ₃₀ ιι together and

d) changing at least one operating parameter of

Turbomachine stage as a function of the comparative efficiency characteristic T | _V gi, where

for determining the actual efficiency value r i i _St , measuring a torque of the rotary shaft of the turbomachine stage is performed. The torque applied to the rotary shaft is measured.

To solve the problem, a turbomachine with at least one turbomachine stage is specified, which has at least one rotary shaft, wherein the

Turbomachine has a device for carrying out the method. The turbomachine is, for example, a turbocompressor, which has several compressor stages

(Turbomachine stages).

The basic idea of the invention is, during operation of the turbomachine on the rotation shaft of the

Turbomachine stage to measure applied torques. Based on the measured torques is on the actual efficiency r | i _St (current efficiency characteristic) of the Turbomachine stage of turbomachine closed.

The current actual efficiency parameter r | i _St the

Turbomachine stage is with the target efficiency characteristic r | _so ii the turbomachine stage compared. The target efficiency characteristic value η ₃₀ ιι is determined separately, for example, for the respective flow machine stage after their completion or after completion of the turbomachine. Also conceivable is the use of a

predetermined, standardized target efficiency value r | _so ii (default).

From the comparison of the actual efficiency characteristic value r | η i _St and the target efficiency characteristic value ₃₀ ιι each other results of the comparative efficiency characteristic value , Based on the

Comparative efficiency factor i ~ | _V gi will at least become one

Operating parameters (process parameters) of the turbomachine stage regulated. The operating parameter is in particular an extent of the voltage applied to the turbomachine stage

Volume flow of the fluid or a speed at which the rotary shaft of the turbomachine stage is driven. With the invention, the turbomachine stage is optimized during operation.

The method can be used for a single-stage turbomachine. The turbomachine has only one turbomachine stage.

In a particular embodiment, a multistage turbomachine with at least one further turbomachine stage, which has at least one further rotary shaft, is used as turbomachine. The turbomachine has at least one further turbomachine stage with at least one further rotary shaft. In this case, for example, the rotation shaft and the further rotation shaft are identical. There is only one common rotary shaft of the turbomachine stages. For example, one is Such multi-stage turbomachine a multi-stage turbocompressor.

The following further method steps are preferably carried out:

a ') determining a further desired efficiency parameter r | _so ii ^Λ the other turbomachine stage,

b ¹ ) determining a further actual efficiency characteristic value ηι _3ί ^{Λ of} the further _turbomachine stage,

ο ^Λ ) Determining a further comparative efficiency parameter r | _vg i ^Λ the other _turbomachine stage by comparing the other actual efficiency characteristic ηι _3ί ^Λ and the other target efficiency characteristic η ₃₀ ιι ^Λ each other and

cP) changing at least one further operating parameter of the further turbomachine stage as a function of the further comparative efficiency characteristic value r | _vg i ^Λ .

In particular, another further measuring a torque of the other rotary shaft of the further flow machines stage performed _St i ^Λ | this case is to determine the further actual efficiency-characteristic value r. It will be another, applied to the other rotation shaft

Torque measured.

In a multistage turbomachine, the method for determining the comparative efficiency characteristic value is carried out for a plurality of turbomachine stages. This is preferably done separately and / or separately for each of the turbomachine stages. Based on the respectively determined comparative efficiency characteristics are

respective operating parameters of the respective

Turbomachine level varies or adjusted. The result is a turbomachine that is optimal

Operating range can be operated with optimized overall efficiency. For the individual, independent determination of the comparative degrees of effectiveness, a torque sensor for determining the actual efficiency characteristic value r | i _{St of} the turbomachine stage and / or at the further rotational shaft is a torque sensor on the rotary shaft. Sensor for determining the further actual efficiency characteristic ηι _3ΐ > the

Turbomachine stage arranged.

Preferably, a non-contact measuring method is performed to measure the torque of the rotary shaft and / or to measure the additional torque of the further rotary shaft. The torque sensor and / or the further torque sensor are non-contact torque sensors.

As a non-contact measuring method, for example, an optical measuring method is performed. The non-contact measuring method is preferably carried out with the aid of a magnetoelastic torque sensor. Of the

non-contact torque sensor is a magneto-elastic torque sensor. A magneto-elastic torque sensor is preferably arranged directly on the respective rotation shaft.

Magnetoelasticity is based on a change in the

magnetic permeability of a ferroelectric material due to mechanical forces acting on the

act ferromagnetic material. By using magneto-elastic torque sensors, it is possible to measure directly during operation of the turbomachine torques and to determine therefrom a corresponding efficiency characteristic value of the respective turbomachine stage of the turbomachine.

With regard to the magneto-elastic measuring principle, it is particularly advantageous to use a rotation shaft of the

Turbomachine stage to use, which consists entirely of ferroelectric material. It is also conceivable that the rotation shaft only partially off ferroelectric material. For example, there is a ferroelectric coating of the rotary shaft fixedly connected to the rotary shaft

ferroelectric material. This ensures that the torque of the rotary shaft can be transferred to the ferroelectric coating by the connection of the ferroelectric coating and the rotary shaft. By the transmission of torque changes the

Permeability of the ferroelectric coating. It

results in a detectable signal that allows a conclusion on the voltage applied to the rotary shaft torque.

According to a particular embodiment, the

Turbomachine selected from the group gas turbine, steam turbine, turbocharger, pump, compressor and hydroturbine. The turbomachine is preferably a compressor, in particular a turbocompressor. Under turbo compressor here are both mechanically driven compressors in the oil and gas sector and combined machines for

Energy conversion understood as gas turbines.

Preferably, an actual efficiency parameter r | i _St and / or a further actual efficiency parameter r | i _St ^Λ

used, which result from the following equation:

Here r i is the respective efficiency characteristic value of

Turbomachinery stage. Pli is the product of the above the respective turbomachine stage i adjacent

Volume flow and applied to the turbomachine stage i pressure difference Δι. P2i is a product of the torque applied to the rotary shaft of the respective turbomachine stage i and the rotational speed of the rotary shaft of the turbomachine stage i.

As operating parameters of the turbomachine various sizes are conceivable. In a particular embodiment is as Operating parameters and / or as a further operating parameter at the turbomachine level applied flow rate of fluid, with which the turbomachine stage is operated, and / or a speed is used, with which the rotary shaft of the turbomachine stage is driven. These operating parameters are dependent on

Comparative efficiency characteristic value changed. Further

Operating parameter is, for example, a position of valves and baffles for the fluid with which the

Turbomachine stage is operated.

With reference to several embodiments and the associated figures, the invention will be described in more detail below. The figures are schematic and represent none

true to scale illustrations.

FIG. 1 shows a single-stage single-shaft compressor. FIG. 2 shows a multi-stage single-shaft compressor.

FIG. 3 shows a transmission compressor.

Given is a turbomachine 1 in the form of a

Turbo compressor with at least one compressor stage

(Turbomachine Stage) 11. The compressor stage 11 has a rotary shaft 111.

On the rotary shaft 111, a torque sensor 112 for determining the actual efficiency characteristic r i _{St of} the compressor stage 11 is arranged. The torque sensor 112 is a magneto-elastic torque sensor.

The turbocompressor 1 has a device 100 for

Carrying out an operating procedure with the following

Procedural steps on:

a) determining the target efficiency characteristic η ₃₀ ιι the

Compressor stage 11, b) determining the actual efficiency value r | i _St the

Compressor stage 11,

c) determining the comparison efficiency characteristic value the compressor stage 11 by comparing the actual efficiency parameter r | i _St and the target efficiency characteristic η ₃₀ ιι each other and

d) changing at least one operating parameter of

Compressor stage 11 as a function of the comparative efficiency characteristic value T |

For determining the actual efficiency characteristic r | i _St , measuring a torque of the rotary shaft 111 of FIG

Compressor stage 11 using the magneto-elastic

Torque sensor 112 performed. There is the

Rotary shaft 111 made of ferroelectric material. In an alternative embodiment, the rotary shaft 111 has a fixed to the rotary shaft 111 connected

ferroelectric coating on. The actual efficiency parameter r i i _{t of} the compressor stage 11 is determined according to equation (1). Likewise, the target efficiency value r | _so ii determined more or less immediately after completion of the turbocompressor 1. The volume flow over the compressor stage 11 to be measured for PI (according to equation (1)) is measured by means of a volumetric flow meter 114.

Furthermore, the necessary for PI pressure difference Δρ 115 between front 116 and back 117 of the compressor stage 11 is measured.

For P2 (according to equation (1)), the torque at the

Rotation shaft 111 measured as described above. The

Speed 113 of the rotary shaft 111 of the compressor stage 11 is known in each case. From the comparison of the actual efficiency characteristic r i _St and the desired efficiency characteristic value η ₃₀ ιι together results in the comparative efficiency characteristic value the compressor stage 11.

Depending on the comparative efficiency value At least one operating parameter of the compressor stage 11 is varied. For this purpose, a pump control 118 is used. The operating parameter is the rotational speed 115 of the rotary shaft 111, which is variable via the control of the motor 13 and / or the volume flow of the fluid, over the

Volumetric flow meter is changeable.

Example 1 :

The turbocompressor 1 is a (axially or radially operated) single-shaft compressor (compressor with only one rotary shaft, Figure 1). Example 2:

In contrast to Example 1, the turbocompressor 1 is a multi-stage single-shaft compressor (Figure 2). Of the

Turbo compressor 1 has a turbocompressor stage 11 and at least one further turbocompressor stage 12.

The rotary shaft 111 of the compressor stage 11 and the further rotary shaft 121 of the further compressor stage 12 form a common rotary shaft.

At the further compressor stage 12, a further magneto ^¬ elastic torque sensor 122 is arranged. With the help of the further torque sensor 122, the further torque in the region of the further rotation shaft 121 is tapped.

The torque sensor 112 and the further torque sensor 122 are operated independently of each other. The

Travel range optimization for the further compressor stage 12 takes place in accordance with the driving range optimization for the compressor stage 11 described above.

Example 3:

The turbocompressor 1 is a transmission compressor (FIG. 3). The compressor stage 11 and the further compressor stage 12 are connected to each other via a gear 14. About the motor 13, the rotary shaft 111 is driven. About the gear 14, the further rotation shaft 12 to the

Rotary shaft 111 coupled.

The torque of the rotary shaft 11 is over the

Torque sensor 112 and the further torque of the further rotation shaft 12 via the further torque sensor 122 measured.

Via the adjustable inlet guide apparatus (ELA) 310 and the adjustable outlet guide apparatus (ALA) 320, the fluid to be compressed is introduced into the gear compressor or the compressed fluid is removed from the gear compressor again.

Other components include a flow meter 330 and devices for measuring the individual

Compressor stages 11 and 12 applied pressure differences 340 and 350th

Claims

claims

1. A method for operating a turbomachine (1) with at least one turbomachine stage (11), the

has at least one rotation shaft (111), wherein the following method steps are carried out:

a) determining a target efficiency characteristic η ₃₀ ιι the

Turbomachine stage (11),

b) determining an actual efficiency value r | i _St the

Turbomachine stage (11),

c) determining a comparative efficiency characteristic value the flow machine stage (11) by comparing the actual efficiency characteristic r | i _St and the target efficiency characteristic r | _so ii with each other and

d) changing at least one operating parameter of

Turbomachine stage (11) as a function of the comparison efficiency characteristic value r | vgi, where

for determining the actual efficiency value r i _St measuring the torque of the rotary shaft (111)

Turbomachine stage (11) is performed.

2. The method of claim 1, wherein as a turbomachine, a multi-stage turbomachine with at least one further turbomachine stage (12) is used, which has at least one further rotation shaft (121).

3. The method of claim 2, wherein the following further

Procedural steps are carried out:

a ') determining a further desired efficiency parameter r | _so ii ^Λ the other turbomachine stage (12),

b ¹ ) determining a further actual efficiency characteristic value r | i _St ^{Λ of} the further turbomachine stage (12),

ο ^Λ ) Determining a further comparative efficiency parameter r | _vg i ^{Λ of} the further turbomachine stage (12) by comparing the further actual efficiency parameter r | i _St ^Λ and the further target efficiency characteristic value η ₃₀ ιι ^Λ with each other and cP) changing at least one further operating parameter of the further turbomachine stage (12) as a function of the further comparative efficiency characteristic value ^Λ .

4. The method of claim 3, wherein

for determining the further actual efficiency characteristic value r | i _St ^Λ measuring a further torque the further rotation (121) of the further flow machine stage (12) is carried out shaft.

5. The method according to any one of claims 1 to 4, wherein for measuring the torque of the rotary shaft (111) and / or for measuring the further torque of the further rotary shaft (121) a non-contact measuring method is performed.

6. The method of claim 5, wherein the non-contact measuring method using at least one magneto-elastic torque sensor (112) is performed.

7. The method according to any one of claims 1 to 6, wherein the turbomachine (1) from the group gas turbine,

Steam turbine, turbocharger, pump, compressor and hydroturbine is selected.

8. The method according to claim 6, wherein as the turbomachine (1), a compressor is used and an actual efficiency characteristic r i _St and / or a further actual efficiency characteristic r i _St ^Λ are used, which from the following equation

result:

Pli = volumetric flow over the respective turbomachine stage i x pressure difference Δι at the turbomachine stage i

P2i = torque on the rotation shaft of the

Turbomachine Stage ix Turbomachine Stage Rotary Shaft Speed i

9. The method according to any one of claims 1 to 8, wherein as an operating parameter and / or as a further Betriebssparamenter an adjoining the turbomachine flow rate of a fluid with which the turbomachine stage is operated, and / or a speed is used with the the rotary shaft of the turbomachine stage is driven.

10. Turbomachine (1) with at least one

Turbomachine stage (11) having at least one rotary shaft (111), wherein the turbomachine (1) comprises a device (100) for performing the method according to one of claims 1 to 9.

11. Turbomachine according to claim 10, wherein the

Turbomachine (1) at least one more

Turbomachine stage (12) having at least one further rotation shaft (121).

12. Turbomachine according to claim 10 or 11, wherein on the rotary shaft (111) has a torque sensor (112) for

Determining the Actual Efficiency Parameter r | i _St the

Turbomachine stage and / or on the further rotation shaft (121), a further torque sensor (122) for

Determining the further actual efficiency characteristic ηι _3ΐ > the _turbomachine stage are arranged.

13. Turbomachine according to claim 12, wherein the torque sensor (112) and / or the further torque sensor (122) is a non-contact torque sensor.

14. Turbomachine according to claim 13, wherein the

Non-contact torque sensor (112, 122) is a magnetoelastic torque sensor.

15. Turbomachine according to one of claims 10 to 14, wherein the turbomachine (1) from the group gas turbine, steam turbine, turbocharger, pump, compressor and hydroturbine is selected.