WO2011006945A1

WO2011006945A1 - Method for simulating an operation of a technical system on the basis of the state variables

Info

Publication number: WO2011006945A1
Application number: PCT/EP2010/060172
Authority: WO
Inventors: Wolfgang Kruppa
Original assignee: Siemens Aktiengesellschaft
Priority date: 2009-07-17
Filing date: 2010-07-15
Publication date: 2011-01-20
Also published as: DE102009033605B4; DE102009033605A1

Abstract

The invention relates to a method for simulating a power plant operation of a power plant system on the basis of state variables, wherein one or more system components of the power plant system are divided into a plurality of segments (S1 to S4, S1' to S18') and, in addition to the metrologically captured state variables of at least one of the system components, a plurality of state variables is ascertained by way of a simulator and determined, segment by segment, for the respective segment (S1 to S4, S1' to S18').

Description

description

Method for simulating an operation of a technical system based on state variables

The invention relates to a method for simulating an operation of a technical system, in particular a power plant operation of a power plant based on state variables.

In general, methods for simulating a power plant operation of a power plant are known, with the aid of known simulators, for example, a power plant personnel trained and / or trained. For example, it is possible to have a temperature profile for a part of the plant

Record power plant based on a set of selected, time-dependent trend curves. However, the selection of these trend curves is limited to values actually measured in the equipment part. As a result, only a selection of characteristic values for the plant part can be observed. Simulators usually provide a wealth of additional information without, however, using it for training purposes, for example. Static temperature profiles for different load points are often provided by a plant operator and / or a plant manufacturer.

From DE 196 18 745 Al a simulation method for a power plant is known, in which, for example, the subarea "primary circuit" is divided into a number of sub-volumes, the simulation of the temporal evolution of each phase ("liquid" and "gaseous") of the Cooling medium is carried out separately for each sub-volume.

DE 196 35 033 A1 discloses a method for analyzing a process state of a technical installation, in which, on the basis of analytical comparisons, for each Part of the current actual state is determined depending on the influential adjacent plant parts.

The invention has for its object to provide a method for simulating an operation of a technical system, in particular a power plant operation of a power plant based on state variables.

The object is achieved by the features indicated in claim 1.

Advantageous developments of the invention are the subject of the dependent claims. An inventive method for simulating an operation of a technical system, in particular a power plant operation of a power plant, based on state variables provides that one or more parts of the plant power plant are divided into a number of segments and in addition to metrologically detected state variables of at least one of the plant parts Variety of state variables determined by means of a simulator and location-dependent, in particular segmentally, ie for the respective segment the associated state variable (s) can be determined.

For example, the plant part may be a countercurrent heat exchanger and / or a flue gas duct of the power plant. Furthermore, the method according to the invention provides that, based on determined values of one or more state variables for one, several or all segments of individual plant sections, a course of the state variable or a location-dependent state profile along the segment or segments is determined and displayed. A possible embodiment of the invention provides that all values of a state variable for a segment are averaged and the segment value of the mean, that is, the average value of the relevant state variable of the respective segment is used.

The inventive method is used in a profitable way to produce a complex relationship between cause and effect, for example, load change within the overall technical system and / or part of the plant and illustrate this complex context, in particular a power plant staff and to illustrate. For example, it can be determined and visualized by means of the method according to the invention how a temperature is distributed during a starting process of the simulated power plant operation and / or which effects result, for example, from an additional fire within the plant part.

In addition, a graphic dynamic representation of the state variables in the form of a location-dependent state profile, i. Location-dependent progressions of several state variables, a stability of the power plant operation by simultaneous control of a variety of state variables are checked with a relatively low cost. As a result, implausibilities can be detected early and instabilities can already be identified during runtime. For example, the respective state variable is determined as a function of at least one system parameter.

In one possible embodiment, for. B. determined as a plant parameter, a medium flowing through the plant part, wherein the respective state variable is determined depending on a mate- rialigenschaft of the system part flowing through the medium.

Alternatively or additionally, the respective state variable can be determined as a function of a material property of a wall of the plant part. Preferably, at least one temperature and / or at least one pressure of at least one plant part, in particular a heat exchanger unit, are determined as state variables. It is also conceivable that the state variables are determined as a function of characteristic values of at least one heating surface arranged in the heat exchanger unit and / or of a heat exchanger arranged in the heat exchanger unit. Furthermore, based on the determined values of one or more state variables of several plant parts, these state profiles can be combined to form a dynamic overall state profile. In one possible embodiment, a determined course of the state variable, the state profile and / or the overall state profile are graphically output. The course of the state variable, the state profile and / or the overall state profile are preferably output or displayed graphically in a coordinate system preferably as a function of the location in the simulator and / or on the operating and monitoring surface of a control system.

Embodiments of the invention are explained in more detail below with reference to drawings. Show:

1 shows a coordinate system with a temperature profile of a plant part, wherein the plant part is divided into four segments,

2 shows a coordinate system with a temperature profile of flowing media within a complete system at full load, wherein the entire system is composed of 16 system parts, which in turn are individually segmented,

3 shows a coordinate system with a temperature profile of flowing media within an overall system according to FIG. 2 at partial load. Corresponding parts are provided in all figures with the same reference numerals.

1 shows a coordinate system 1 with a temperature profile P, which was determined within a plant part, in particular a Gegenstromwärmeübertragers represented.

The coordinate system 1 is output as a result of a simulation of a power plant operation of a power plant in a particularly advantageous manner in the simulator and / or on an operating and monitoring surface of a control system.

A counterflow heat exchanger is a device that transfers thermal energy from a first medium M1 to a second medium M2. Countercurrent here means that the media Ml, M2 countercurrently flow past each other and in the ideal case, the temperatures of the flowing past each other media Ml, M2 are exchanged. That is, an originally cold medium reaches a temperature of the originally hot medium, and vice versa.

The abscissa of the coordinate system 1 represents the location s within the Gegenstromwärmeübertragers, wherein the counter-current heat exchanger is divided as part of the plant in four equal segments Sl to S4 and thus the abscissa is divided into four equal segments Sl to S4 analog.

The ordinate indicates the state quantity, which in the present embodiment is a temperature of the media M1, M2.

Alternatively or additionally, as a state variable, for example, a pressure within the plant part can be determined.

In the present embodiment, in the coordinate system 1, two temperature curves Tl, T2 in opposite set direction flowing media Ml, M2 shown. In this case, a first temperature profile Tl represents a change in the temperature of the first medium M1 when it flows through the system part in the form of the countercurrent heat exchanger. A second temperature profile T2 indicates the change in the temperature of the second medium M2.

For example, the first medium Ml is a flue gas and the second medium M2 is a water / Dampfström, wherein within the Gegenstromwärmeübertragers based on the temperature characteristics

Tl, T2 can be seen that a heat of the first medium Ml is transferred to the second medium M2.

The first medium Ml flows according to Figure 1 from left to right, wherein an inlet El of the first medium Ml takes place in a first segment Sl. The second medium M2 flows counter to, wherein an inlet E2 of the second medium M2 takes place in a fourth segment S4 of the countercurrent heat exchanger.

It is provided that for each segment Sl to S4 of the countercurrent heat exchanger at least one value of the state variable, for. B. temperature value Tl _s i to T1 _S 4 for the first medium Ml, and at least one temperature value T2 _S i to T2 _{S4 of} the second medium M2 are determined. Preferably, an average value of all values of the state variable in the respective segment S 1 to S 4 is determined and used as the segment state value for the simulation. In addition, the respective state variable can be determined as a function of at least one system parameter, a material property of the media M 1, M 2 flowing through the system component, and / or a material property of a wall of the system component.

From the determined temperature values Tl _S i to T1 _S 4 and

T2 _S i to T2 _S 4 is for the respective medium Ml, M2 an interpolation curve as a temperature profile Tl, T2 of the state variable Temperature determined. A first interpolation curve here identifies the first temperature profile Tl of the first medium M1 within the four segments S1 to S4, and a second interpolation curve identifies the second temperature profile T2 of the second medium T2 within the four segments S1 to S4. Here, the respective temperature profile Tl, T2 is shown as a function of the location s, in particular as a function of the segments Sl to S4. On the basis of the representation of the first and the second temperature profile Tl, T2 as a state or temperature profile P (hereinafter called temperature profile P for clarity), a temperature difference .DELTA.T between the media Ml, M2 visualized and in the simulator and in a particularly advantageous manner / or output on the operator control and monitoring interface of the control system.

The temperature difference .DELTA.T in this case is a measure of a possible heat transfer between the first and the second medium Ml, M2 and can be illustrated by the method in a particularly advantageous manner. Thus, a performance and / or efficiency of the simulated Gegenstromwärmeübertragers can or can be illustrated. In addition, the values of the state variables can be measured.

In FIGS. 2 and 3, a coordinate system 2 is shown in each case, wherein the coordinate system 2 in FIG. 2 has a temperature profile of a full load case as overall condition profile P '

(hereinafter referred to as overall temperature profile P 'for clarity) and the coordinate system 2 shown in FIG. 3 as total state profile P''a temperature profile of a partial load case of the entire system, for example a flue gas duct of a power plant, as a result of a combination of state, in particular temperature profiles P is based on several plant components. In particular, the overall temperature profile P ', P "of the flue gas duct is shown in the coordinate system 2 shown in FIG. 2 and FIG. In the present exemplary embodiment, the flue gas duct is subdivided into a total of 16 system components, in particular 16, heating surfaces Hl to H16.

Here, each heating surface Hl to H16 is a certain part of the plant, such. As a low-pressure evaporator, a feedwater, a medium-pressure evaporator, a medium-pressure superheater and / or a high-pressure superheater assigned.

The system components in the form of the heating surfaces H1 to H16 are each subdivided into a specific number of segments S1 'to S18' in the simulation model analogously to the segmentation of a countercurrent heat exchanger described above.

For the segments S 1 'to S 18', the state variables to be displayed, the temperature values, z. B. average temperatures, the flowing through the flue gas channel media Ml, M2 determined in the simulation model and dynamically displayed location-dependent graphically. In this case, each segment S 1 to S 18 of an installation part in the overall temperature profile P ', P "is represented by means of a single point, pixel, square or the like, wherein the point, the pixel or the square can be controlled individually. A composition of these individual points of a plant part, in particular a heating surface Hl to H16 gives the temperature profile P of this part of the plant. A combination of several or all of the temperature profiles P of several or all plant components gives the total temperature profile P ', P "of plant areas and / or of the entire plant. A course of the state profile of a plant part, in particular a heating surface Hl to H16 is formed in the present embodiment by stringing individual values of the individual segments Sl 'to S18.

This results in a local first temperature profile Tl 'of the first medium Ml based on the thick solid line and a second temperature profile T2 of the second medium M2 shown by the dashed line. In addition, a first temperature profile Tl '' of the first medium Ml is shown in accordance with a thermal circuit diagram at full load on the basis of the solid thin line.

A flow direction of the media Ml, M2 is largely countercurrent, wherein the media Ml, M2, as described above, flow past each other in the opposite direction. An inlet El 'of the first medium M1, for example flue gas, takes place from the right, that is to say in the segment S18 of the heating surface H16. During a flow to the left, the first medium Ml cools through the countercurrent second medium M2, water / steam. A flow of the second medium M2 takes place except at the heating surfaces Hl to H16 in the form of evaporators, from left to right, in which case a continuous total temperature profile P ', P' 'results, if corresponding inlets and outlets of the second medium M2 the heating surfaces Hl to H16 are set together.

For example, the respective state variable of the media M1, M2 is determined as a function of characteristic quantities of the heating surfaces H1 to H16 arranged in the plant part. By means of the method according to the invention, it is possible in a particularly advantageous manner, based on the determined values of one or more state variables for individual segments

Sl to S4, Sl 'to S18' to determine a course of the state variable, a state profile P and / or a dynamic overall state profile P ', P "segment by segment and graphically represented by means of the coordinate system 1.

For example, during a training scenario for power plant personnel, it is possible to illustrate a complex interaction of heating surfaces H1 to H16 when the load changes within the plant part by displaying a dynamic location-dependent temperature profile P, P ', P ". It can be shown very clearly how, for example, changes in temperature at corresponding heating surfaces

Hl to H16 on more, z. B. arranged in the plant part,

Heating surfaces Hl to H16 impact. Furthermore, can be illustrated by the graphical representation of how a temperature distribution during a starting process z. B. the power plant operation represents and / or how strong an additional fire affects. It should be noted that the location-dependent representation of the state profile / e P and / or of the overall state profile (s) P ', P "always represents a very clear overview of a current state of a simulated plant part or of the entire plant , Thus, the location-dependent representation of the state profile / e P and / or the overall state profile P ', P "is a very good complement to the time-dependent trend curves mentioned in the prior art.

It is also possible to statically characterize the state profile / s P and / or the overall state profile P ', P "in the coordinate system 1, 2 for different load points, so that on the basis of the determined state profile / e P and / or of the determined total state profile / s P ', P "an instantaneous load can be estimated. The described dynamic location-dependent state and / or overall state profiles P, P ', P ", for example with respect to the temperature of the media M 1, M 2 flowing in the plant part, allow a modeler to have a simulated power plant operation stability by simultaneously controlling a plurality of state variables to check with relatively little effort. implausible

and / or instabilities can be detected early during a run time without much effort. By statically entering different load points into the respective coordinate system 1, 2, it is possible, after approaching different load points, to obtain an overview of the quality and / or accuracy of the simulation of a simulation. onsmodells. The state profile / s P

and / or the overall state profile P ', P "may be taken into account for decreases or they may assist the modeler in fine-tuning a variety of parameters.

Claims

claims

1. A method for simulating a power plant operation of a power plant based on state variables, wherein

one or more plant parts of the power plant in a number of segments (Sl to S4, Sl 'to S18') are divided and determined in addition to metrologically detected state variables of at least one of the plant parts, a plurality of state variables by means of a simulator and segment by segment for each segment (Sl to S4, Sl 'to S18') are determined,

characterized in that based on the determined values of one or more state variables for individual segments (Sl to S4, Sl 'to S18'), a profile of the state variable or a state profile along the segment (Sl to S4, Sl 'to S18') is determined ,

2. The method according to claim 1,

characterized in that the respective state variable is determined as a function of at least one system parameter.

3. The method according to claim 1 or 2,

characterized in that the respective state variable is determined as a function of a material property of a medium flowing through the installation part (Ml, M2).

4. The method according to any one of claims 1 to 3,

characterized in that the respective state variable is determined as a function of a material property of a wall of the plant part.

5. The method according to any one of claims 1 to 4,

characterized in that at least one temperature and / or at least one pressure of at least one system part, in particular a heat exchanger unit, are determined as state variables.

6. The method according to claim 5,

characterized in that the state variables are determined as a function of characteristics of at least one heating surface (Hl to H16) arranged in the heat exchanger unit and / or of a heat exchanger arranged in the heat exchanger unit.

7. The method according to any one of claims 1 to 6,

characterized in that based on the determined values of a plurality of state variables of a plurality of segments (Sl to S4, Sl 'to S18') a plurality of state profiles are determined segment by segment and combined to form a dynamic overall state profile.

8. The method according to any one of claims 1 to 7,

characterized in that the determined course of the state variable, the state profile and / or the overall state profile is or will be graphically output.

9. The method according to claim 8,

characterized in that the determined course of the state variable, the state profile and / or the overall state profile are graphically output in a coordinate system (1, 2).

10. The method according to claim 9,

characterized in that the determined course of the state variable, the state profile and / or the overall state profile in the coordinate system (1, 2) is / are output as a function of a location (s).