DE102018104665B4 - Method for operating an internal combustion engine, control device and internal combustion engine - Google Patents

Abstract

Method for operating an internal combustion engine with a motor and a further component, the internal combustion engine having: - a machine component that can limit the running time for the operation of the internal combustion engine, - a number of operating media that are used to operate the internal combustion engine, namely for operation of the engine and. are supplied to, removed from or kept in the further component, - a device which is designed to at least monitor the operation of the internal combustion engine, wherein in the method: - operating data of the internal combustion engine and the operating media are determined, and - for the operation of the internal combustion engine a time interval of the machine component that limits the running time is specified, namely a time interval until the next maintenance of the internal combustion engine, - operating data of the machine component are determined by determining those operating data that are in an effective connection with an actual load profile of the machine component, wherein these operating data include at least one media temperature of one of the operating media, and - the at least one media temperature is measured as transient operating data, - the causal relationship is represented by means of a calculation or data specification such that a machine component temperature tr ansient is determined from the transient medium temperature, the transient machine component temperature being determined at at least a first and/or a second component location and a temporal and/or local temperature change for the component being specified therefrom, characterized in that- by means of the transient machine component -Temperature at least one temperature change amplitude of the machine component temperature is specified and classified as the basis of an operating pattern characterizing the operation of the machine component, namely a number of load classes for the operation of the machine component is determined, and- by means of a number of load classes and/or load class changes Operating pattern of the machine component is specified - based on the operating pattern, the time interval limiting the running time of the machine component for the operation of the internal combustion engine is specified.

Description

The invention relates to a method according to the preamble of claim 1 for operating an internal combustion engine with a motor and another component such as a turbocharger, heat exchanger or the like. The invention also relates to a control device and an internal combustion engine.

• - ein Maschinenbauteil, das Laufzeit begrenzend für den Betrieb der Brennkraftmaschine sein kann, wie etwa eine Motorkomponente oder eine Abgasturbolader-Komponente oder dergleichen oder ein insbesondere bewegliches Bauteil derselben,
• - eine Anzahl von Betriebsmedien, die zum Betrieb der Brennkraftmaschine genutzt werden, nämlich zum Betrieb des Motors und der weiteren Komponente wie etwa dem Turbolader zugeführt, abgeführt oder in diesen gehalten werden, insbesondere ein Abgas, eine Ladeluft, ein Kraftstoff, einen Schmierstoff, ein Kühlmittel oder dergleichen,
• - eine Einrichtung, die ausgebildet ist, den Betrieb der Brennkraftmaschine wenigstens zu überwachen, insbesondere zu steuern und/oder zu regeln.

The internal combustion engine has:

• - a machine component that can limit the running time for the operation of the internal combustion engine, such as an engine component or an exhaust gas turbocharger component or the like or a particularly moving component thereof,
• - a number of operating media that are used to operate the internal combustion engine, namely to operate the engine and other components such as the turbocharger, are supplied, discharged or kept in them, in particular an exhaust gas, charge air, a fuel, a lubricant coolant or the like,
• - A device that is designed to at least monitor the operation of the internal combustion engine, in particular to control and/or regulate it.

• - Betriebsdaten der Brennkraftmaschine und der Betriebsmedien bestimmt werden, sowie
• - für den Betrieb der Brennkraftmaschine ein die Laufzeit begrenzendes Zeitintervall des Maschinenbauteils angegeben wird, nämlich ein Zeitintervall bis zu einer nächsten Wartung der Brennkraftmaschine wie etwa ein präventives Tausch- oder Überholungsintervall für das Maschinenbauteil.

The procedure provides, inter alia, that:

• - Operating data of the internal combustion engine and the operating media are determined, as well as
• - For the operation of the internal combustion engine, a time interval limiting the running time of the machine component is specified, namely a time interval until the next maintenance of the internal combustion engine, such as a preventive replacement or overhaul interval for the machine component.

It has been known for a long time to design the operation of internal combustion engines and other drive components of a vehicle as operationally as possible - that is, to design machine parts of the internal combustion engine or the components of the internal combustion engine in such a way that they can achieve a certain finite service life with a given probability without unnecessary expenditure on material. At least, however, a time interval that limits the running time of one or more machine components should be specified for the operation of the internal combustion engine, which can limit the running time for the operation of the internal combustion engine.

An article by Vahlensieck from April 1999 (54th volume Landtechnik 4/99) is known with regard to an operationally reliable design of drive technology. As part of this article, as well as in other discussions, the "rainflow" count is explained, which, with available computing power, makes it possible to classify load profiles on a machine component to create a load collective and to calculate machine component damage from this, which per load class - ultimately from the quotient "number of load cycles to be endured" (from the load spectrum) divided by "number of load cycles to be endured" (from a limit characteristic; so-called Wöhler curve) - indicates a damage number or, in the reciprocal value, a measure for a reserve distance to the limit characteristic. By summing up the damage to parts, a degree of damage can be specified for an operationally stable design or, from a distance to the limit characteristic curve, a time interval that limits the running time of the machine component can be specified.

From the article by Köhler et al "Counting methods and load assumption in the operational stability" published in Heidelberg by Springer, 2012. - ISBN 978-3-642-13163-9 the most important counting methods used in the field of operational stability are described and evaluated; Such counting methods for classifying stress-time functions are specified in standards and technical regulations. On page 112 ff in Chapter 9.1, the Palmgren-Miner rule is described for a corresponding counting method for estimating the service life, with the total damage being reached when the limit value for which failure is assumed is reached through addition or accumulation of the damage. A damage criterion must be defined for this, for example macroscopic cracking or fracture.

it's over DE 10 2005 048 532 A1 Known for monitoring a mechanical component of a vehicle or engine or other component, operating data to capture and based on the operating data to determine a parameter for the condition of the component, so that an impending failure of the component can be identified and the vehicle controlled can be that an instantaneous load on the component is reduced.

Out of DE19959526A1 a method for detecting faults in a motor vehicle is known, with operating parameters being recorded in order to enable faults in the vehicle to be detected predictively. For this purpose, a pattern of operating parameters is created, which is described in a suitable form so that currently recorded operating parameters can be compared with the pattern of operating parameters.

Such approaches are kept comparatively general. It turns out, however, that ultimately the data acquisition and the causal basis for the reliable specification of a time interval limiting the runtime of the machine component are problematic.

To solve this problem, it is generally known that the transient operation of an internal combustion engine in an internal combustion engine leads to repeated heating and cooling of the engine or other components and in any case this type of load can be regarded as essential for the material fatigue of the components of an internal combustion engine.

In WO 2015/052 274 A1 a method for estimating the damage to at least one technical component of an internal combustion engine is specified; A virtual stress sensor is proposed to reduce the sensory effort for damage monitoring and remaining service life prediction to a minimum. The virtual stress sensor allows the prediction of the visco-plastic stress/strain behavior on the basis of a temperature result from the virtual temperature sensor, as preliminary work for a damage prediction. The method is specified with the following steps: providing at least one virtual temperature sensor for the component; providing at least one virtual stress sensor for the component; Determining a transient temperature of the component of the internal combustion engine using the virtual temperature sensor on the basis of at least one engine or operating or route parameter from the group of engine torque, engine speed, engine power, coolant mass flow, coolant temperature, ambient temperature and route profile, with at least one parameter preferably being in an electronic control unit is filed; determining the stresses of the component of the internal combustion engine by means of the virtual stress sensor on the basis of a predefined total strain tensor and the temperature of the component determined by means of the virtual temperature sensor; Determination of the plastic strains of the component on the basis of the material model; Summation of the visco-plastic strain of the component. Determination of the damage to the component based on the accumulated plastic strains. The virtual temperature sensor can be generated on the basis of a mathematical model for a component and calibrated for the stationary and transient case. An algorithm for determining damage to at least one technical component can be implemented in the electronic control unit (ECU) of the internal combustion engine.

In any case, it is desirable to use this thermal fatigue of the components of an internal combustion engine in an improved manner in order to specify a time interval that limits the running time for a machine part of one of the components.

This is where the invention comes in, the object of which is to specify a method, a control device and an internal combustion engine which makes it possible to specify a time interval for the operation of the internal combustion engine that limits the running time of a machine component in a reliable yet efficient manner.

This object is achieved by a method according to claim 1.

• - Betriebsdaten des Maschinenbauteils bestimmt werden, indem diejenigen Betriebsdaten ermittelt werden, die in einem Wirkzusammenhang mit einem, insbesondere tatsächlichen, Lastverlauf des Maschinenbauteils stehen, wobei diese Betriebsdaten wenigstens eine Medientemperatur eines der Betriebsmedien umfassen, und
• - die wenigstens eine Medientemperatur als transiente, insbesondere zyklische, Betriebsdaten gemessen wird,
• - der Wirkzusammenhang mittels einer Vorschrift, nämlich einer Rechen- oder Datenvorschrift, dargestellt wird derart, dass eine Maschinenbauteil-Temperatur transient bestimmt wird aus der transienten Medientemperatur, wobei die transiente Maschinenbauteil-Temperatur an wenigstens einem ersten und/oder einem zweiten Bauteilort bestimmt wird und daraus eine zeitliche und/oder örtliche Temperaturänderung für das Bauteil angegeben wird. Erfindungsgemäß ist vorgesehen, dass mittels der transienten Maschinenbauteil-Temperatur wenigstens eine Temperaturänderungs-Amplitude der Maschinenbauteil-Temperatur angegeben und als Grundlage eines den Betrieb des Maschinenbauteils kennzeichnendes Betriebsmusters klassiert wird, insbesondere eine Anzahl von Lastklassen für den Betrieb des Maschinenbauteils ermittelt wird, und
• - mittels einer Anzahl von Lastklassen und/oder Lastklassenwechsel ein Betriebsmuster des Maschinenbauteils angegeben wird,
• - auf Grundlage des Betriebsmusters das die Laufzeit begrenzende Zeitintervall des Maschinenbauteils für den Betrieb der Brennkraftmaschine angegeben wird.

The invention is based on a method of the type mentioned; it being provided that

• - Operating data of the machine component are determined by determining those operating data that are in an effective connection with an, in particular actual, load profile of the machine component, these operating data comprising at least one media temperature of one of the operating media, and
• - the at least one medium temperature is measured as transient, in particular cyclic, operating data,
• - the functional relationship is represented by means of a rule, namely a calculation or data rule, such that a machine component temperature is transiently determined from the transient media temperature, with the transient machine component temperature being determined at at least a first and/or a second component location and from this a temporal and/or local temperature change for the component is indicated. According to the invention, at least one temperature change amplitude of the machine component temperature is specified by means of the transient machine component temperature and classified as the basis of an operating pattern characterizing the operation of the machine component, in particular a number of load classes for the operation of the machine component are determined, and
• - an operating model of the machine component is specified by means of a number of load classes and/or load class changes,
• - Based on the operating pattern, the time interval limiting the running time of the machine component for the operation of the internal combustion engine is specified.

The invention is initially based on the consideration that, in order to determine a load capacity of a component of the internal combustion engine or a machine part of the internal combustion engine or one of the components, a degree of wear of the same can be determined, which goes back to the thermal fatigue of the same.

The reason for this was recognized within the framework of this consideration that in particular transient, in particular cyclically occurring, damaging temperature changes of the machine component should be recorded. Based on this consideration, it was also recognized that damaging temperature changes not only relate to temperature changes over time at one location on the machine component, but also, above all, to varying local heating of the component over a certain local extent of the component; so in this respect local temperature gradients on the machine component.

It is therefore provided that the operating data of the machine component are determined by determining those operating data that are in an effective connection with
a, in particular actual, load profile of the machine component, these operating data comprising at least one media temperature of one of the operating media, and the at least one media temperature being measured as transient, in particular cyclic, operating data.

The invention is also based on the consideration that such information could of course basically be obtained by applying suitable sensors to the machine component or components of the internal combustion engine. However, the invention has recognized that this would make the internal combustion engine more expensive and also reduce reliability, since it would ultimately suffer as a result of a sensor failure or the like. Such an approach is at best used as an auxiliary measure in order to improve competitiveness, i. H. in particular, not to endanger the production and maintenance costs of the internal combustion engine.

Provision is therefore made for the functional relationship to be represented by means of a rule, namely a calculation or data rule, in such a way that a transient machine component temperature is determined from the transient media temperature, with the transient machine component temperature being at least a first and/or a second component location is determined and a temporal and / or local temperature change for the component is specified.

The invention has therefore recognized that the determination of operating data of the internal combustion engine and the operating media of the same is advantageous in order to specify a time interval of the machine component that limits the running time for the operation of the internal combustion engine. In particular, the invention has recognized that the operating times of the internal combustion engine and also the operating media are determined in principle. Proceeding from this finding, the invention therefore proposes determining those operating data that are in an effective connection with an actual load profile of the machine component, with these operating data comprising at least one media temperature of one of the operating media. According to the concept of the invention, this approach represents a so-called “virtual sensor” by means of which the temperature-related actual load profile of the machine component that is actually of interest can be determined.

According to the invention, the invention assumes that the operating data should therefore include at least one media temperature of one of the operating media and the at least one media temperature is measured as transient, in particular cyclic, operating data. The invention further proposes that the functional relationship be represented by means of an algorithm in such a way that a machine component temperature is transiently determined from the transient media temperature. In concrete terms, the “virtual sensor” mentioned above is implemented by a computing module, with the help of which a transient temperature change in the media temperature is deduced from the transient temperature change in the medium temperature --resolved in terms of time and/or location.

By means of the transient machine component temperature, at least one temperature change amplitude of the machine component temperature can be specified and classified as the basis of an operating pattern that characterizes the operation of the machine component, with a number of load classes for the operation of the machine component being determined in particular, and by means of a number of load classes and/or load class changes, an operating pattern of the machine component can be specified, and based on the operating pattern the time interval of the machine component that limits the running time for the operation of the internal combustion engine can be specified.

The invention also leads to a control device according to claim 14 and an internal combustion engine according to claim 16 with the control device, it being possible for the method according to the invention to be implemented by the device.

• - eine Überwachungseinrichtung, die ausgebildet ist, den Betrieb der Brennkraftmaschine wenigstens zu überwachen,
• - eine Erfassungseinrichtung mittels der Betriebsdaten der Brennkraftmaschine und der Betriebsmedien bestimmt werden, wobei
• - eine Bestimmungseinrichtung mittels der für den Betrieb der Brennkraftmaschine ein die Laufzeit begrenzendes Zeitintervall des Maschinenbauteils angegeben wird, nämlich ein Zeitintervall bis zu einer nächsten Wartung der Brennkraftmaschine, wie etwa ein präventives Tausch- oder Überholungsintervall für das Maschinenbauteil, wobei

die Steuereinrichtung derart ausgebildet ist, dass:

• - Betriebsdaten des Maschinenbauteils zu bestimmen, indem diejenigen Betriebsdaten ermittelt werden, die in einem Wirkzusammenhang mit einemtatsächlichen Lastverlauf des Maschinenbauteils stehen, wobei diese Betriebsdaten wenigstens eine Medientemperatur eines der Betriebsmedien umfassen, und
• - die wenigstens eine Medientemperatur als transiente, insbesondere zyklische, Betriebsdaten gemessen wird,
• - der Wirkzusammenhang mittels einer Rechen- oder Datenvorschrift dargestellt wird derart, dass eine Maschinenbauteil-Temperatur transient bestimmt wird aus der transienten Medientemperatur, wobei die transiente Maschinenbauteil-Temperatur an wenigstens einem ersten und/oder einem zweiten Bauteilort bestimmt wird und daraus eine zeitliche und/oder örtliche Temperaturänderung für das Bauteil angegeben wird. Erfindungsgemäß ist vorgesehen, dass mittels der transienten Maschinenbauteil-Temperatur wenigstens eine Temperaturänderungs-Amplitude der Maschinenbauteil-Temperatur angegeben und als Grundlage eines den Betrieb des Maschinenbauteils kennzeichnendes Betriebsmusters klassiert wird, nämlich eine Anzahl von Lastklassen für den Betrieb des Maschinenbauteils ermittelt wird, und
• - mittels einer Anzahl von Lastklassen und/oder Lastklassenwechsel ein Betriebsmuster des Maschinenbauteils angegeben wird,
• - auf Grundlage des Betriebsmusters das die Laufzeit begrenzende Zeitintervall des Maschinenbauteils für den Betrieb der Brennkraftmaschine angegeben wird.

The invention thus relates to a control device according to claim 14; namely, in particular, comprising a control device for an internal combustion engine, in particular for carrying out a method according to the concept of the invention

• - a monitoring device which is designed to at least monitor the operation of the internal combustion engine,
• - A detection device by means of the operating data of the internal combustion engine and the operating media are determined, wherein
• - a determination device by means of which a time interval of the machine component that limits the running time for the operation of the internal combustion engine is specified, namely a time interval until the next maintenance of the internal combustion engine, such as a preventive replacement or overhaul interval for the machine component, wherein

the control device is designed in such a way that:

• - to determine operating data of the machine component by determining those operating data which are in an effective connection with an actual load profile of the machine component, these operating data comprising at least one media temperature of one of the operating media, and
• - the at least one medium temperature is measured as transient, in particular cyclic, operating data,
• - the causal relationship is represented by means of a calculation or data specification such that a machine component temperature is transiently determined from the transient medium temperature, the transient machine component temperature being determined at at least a first and/or a second component location and a temporal and/or or local temperature change for the component is specified. According to the invention, at least one temperature change amplitude of the machine component temperature is specified by means of the transient machine component temperature and classified as the basis of an operating pattern characterizing the operation of the machine component, namely a number of load classes for the operation of the machine component are determined, and
• - an operating model of the machine component is specified by means of a number of load classes and/or load class changes,
• - Based on the operating pattern, the time interval limiting the running time of the machine component for the operation of the internal combustion engine is specified.

• - die Brennkraftmaschine ausgebildet ist für den Betrieb mit einer Anzahl von Betriebsmedien, die zum Betrieb der Brennkraftmaschine genutzt werden, wie etwa dem Motor und ggfs. weiteren Komponenten wie etwa dem Turbolader zugeführt, abgeführt oder in diesen gehalten werden, insbesondere ein Abgas, eine Ladeluft, ein Kraftstoff,, eine Schmierstoff, ein Kühlmittel oder dergleichen, und aufweist:
• - ein Maschinenbauteil, das Laufzeit begrenzend für den Betrieb der Brennkraftmaschine sein kann, wie etwa eine Motorkomponente oder eine Abgasturbolader-Komponente oder dergleichen oder ein insbesondere bewegliches Bauteil derselben,
• - eine Überwachungseinrichtung, die ausgebildet ist, den Betrieb der Brennkraftmaschine wenigstens zu überwachen,
• - eine Erfassungseinrichtung mittels der Betriebsdaten der Brennkraftmaschine und der Betriebsmedien bestimmt werden, wobei
• - eine Bestimmungseinrichtung mittels der für den Betrieb der Brennkraftmaschine ein die Laufzeit begrenzendes Zeitintervall des Maschinenbauteils angegeben wird, nämlich ein Zeitintervall bis zu einer nächsten Wartung der Brennkraftmaschine wie etwa ein präventives Tausch- oder Überholungsintervall für das Maschinenbauteil, wobei

die Steuereinrichtung derart ausgebildet ist, dass:

• - Betriebsdaten des Maschinenbauteils zu bestimmen, indem diejenigen Betriebsdaten ermittelt werden, die in einem Wirkzusammenhang mit einem tatsächlichen Lastverlauf des Maschinenbauteils stehen, wobei diese Betriebsdaten wenigstens eine Medientemperatur eines der Betriebsmedien umfassen, und
• - die wenigstens eine Medientemperatur als transiente, insbesondere zyklische, Betriebsdaten gemessen wird,
• - der Wirkzusammenhang mittels einer Vorschrift, insbesondere Algorithmus oder dergleichen Rechen- oder Datenvorschrift, dargestellt wird derart, dass eine Maschinenbauteil-Temperatur transient bestimmt wird aus der transienten Medientemperatur, wobei die transiente Maschinenbauteil-Temperatur an wenigstens einem ersten und/oder einem zweiten Bauteilort bestimmt wird und daraus eine zeitliche und/oder örtliche Temperaturänderung für das Bauteil angegeben wird.

Furthermore, the invention thus relates to an internal combustion engine of claim 16; namely in particular an internal combustion engine with a control device according to the concept of the invention and with a motor and a further component such as a turbocharger, heat exchanger or the like, wherein

• - The internal combustion engine is designed for operation with a number of operating media that are used to operate the internal combustion engine, such as the engine and possibly other components such as the turbocharger, are discharged or held in them, in particular an exhaust gas, a charge air , a fuel, a lubricant, a coolant or the like, and comprises:
• - a machine component that can limit the running time for the operation of the internal combustion engine, such as an engine component or an exhaust gas turbocharger component or the like or a particularly moving component thereof,
• - a monitoring device which is designed to at least monitor the operation of the internal combustion engine,
• - A detection device by means of the operating data of the internal combustion engine and the operating media are determined, wherein
• - A determination device by means of which a time interval of the machine component that limits the running time for the operation of the internal combustion engine is specified, namely a time interval until the next maintenance of the internal combustion engine, such as a preventive exchange or overhaul interval for the machine component, wherein

the control device is designed in such a way that:

• - To determine operating data of the machine component by determining those operating data that are in an effective connection with an actual load profile of the machine component, these operating data comprising at least one media temperature of one of the operating media, and
• - the at least one medium temperature is measured as transient, in particular cyclic, operating data,
• - The functional relationship is represented by a rule, in particular an algorithm or similar calculation or data rule, such that a machine component temperature is transiently determined from the transient Media temperature, the transient machine component temperature being determined at at least a first and/or a second component location and a temporal and/or local temperature change for the component being specified therefrom.

• - mittels einer Anzahl von Lastklassen und/oder Lastklassenwechsel ein Betriebsmuster des Maschinenbauteils angegeben wird,
• - auf Grundlage des Betriebsmusters das die Laufzeit begrenzende Zeitintervall des Maschinenbauteils für den Betrieb der Brennkraftmaschine angegeben wird.

According to the invention, at least one temperature change amplitude of the machine component temperature is specified by means of the transient machine component temperature and classified as the basis of an operating pattern characterizing the operation of the machine component, namely a number of load classes for the operation of the machine component are determined, and

• - an operating model of the machine component is specified by means of a number of load classes and/or load class changes,
• - Based on the operating pattern, the time interval limiting the running time of the machine component for the operation of the internal combustion engine is specified.

Advantageous developments of the invention can be found in the subclaims and specify advantageous possibilities in detail for realizing the concept explained above within the scope of the task and with regard to further advantages.

The transient media temperature is advantageously examined for a persistence time at a temperature level. A dwell time can preferably be determined from the time in which the medium temperature is comparatively constant or has a flat profile with a low gradient or rate of change. In particular, a load change for the machine component and a subsequent temperature change in the temperature of the machine component are already inferred from the presence of a temperature level, preferably with a specific dwell time. Relevant dwell times can be determined differently and individually for the operating medium. Idealized models can be used for investigation and determination. With this stipulation, relevant load change initiating changes in the medium temperature can be recorded qualitatively and quantitatively.

Advantageously, the machine component temperature is determined as a time-dependent curve for the machine component using principles of heat and mass transfer theory. This can be done in particular at a single location and/or at a number of locations on the machine component. In particular, the time-dependent curve for the machine component can be determined as a time-dependent exponential function. The time-dependent exponential function can preferably have parameters for an initial temperature, a maximum temperature increase and an increase in the temperature profile on the machine component. With this functionality and measures for determining the machine component temperature as a time-dependent curve for the machine component, the so-called “virtual sensor” is advantageously implemented, by means of which the temperature-related actual load curve of the machine component that is actually of interest can be determined.

Parameters of the time-dependent profile of the machine component temperature are advantageously determined empirically and/or based on a model. Both variants have their advantages; empirical determination is more accurate in most cases. The empirical determination can quantify the parameters, in particular as operating point-dependent characteristic fields.

A transient machine component temperature is advantageously determined at at least a first and a second point in time; preferably at an upper temperature level and a lower temperature level for the dwell times, which indicate a load change for the machine component. A temperature change over time at at least one component location can preferably be specified from this. In particular, at least one temperature change amplitude of the machine component temperature can be specified by means of the transient machine component temperature; preferably as the difference between an upper temperature level and a lower temperature level. The temperature change amplitudes can then be classified in such a way that a “temporal” load class based thereon is determined from the temperature change over time as the basis of an operating pattern characterizing the operation of the machine component.

In particular, this can be carried out for further component locations of a component, in particular for further components. Analogously, the transient machine component temperature can advantageously be determined at at least a first and a second component location, preferably at least at a specified point in time, and from this a local temperature change amplitude for the component can be specified and classified. This can advantageously be implemented in such a way that a “local” load class based thereon is determined from the local temperature change as the basis of an operating pattern that characterizes the operation of the machine component.

As part of a particularly preferred development can from the time and / or location If there is a temperature change and/or a preferred temperature change amplitude mentioned, a number of load classes can be determined as the basis of an operating pattern that characterizes the operation of the machine component.

A frequency of the load class change can advantageously be specified using the operating pattern of the machine component. This advantageously takes into account for the component at the corresponding location of the component the frequency with which it is changed into or out of a load class. This is based on the finding that the change in load, in particular a cyclic change in load in the sense of first reducing the load and then increasing the load again, is of particular importance in relation to a specific load class when determining component damage. The time interval of the internal combustion engine that limits the running time can advantageously be specified by means of the number of load class changes.

Advantageously, a total number of predetermined load classes, in particular for loads outside of nominal operation and/or extreme loads, can already be determined for the operation of the machine component, such that an operating pattern of the machine component is specified using the total number of predetermined load classes. This is based on the finding that changing a load to one of the predetermined load classes, in particular for loads outside of nominal operation and/or extreme loads, is of particular importance when determining component damage. Advantageously, the number of determined load classes, in particular the number of determined predetermined load classes, can then already be used to indicate the time interval of the internal combustion engine that limits the running time.

As part of a particularly preferred development, the time interval of the internal combustion engine that limits the running time can be determined from a damage number. A damage number basically follows the principle mentioned at the beginning, as described in the article by Vahlensieck from April 1999 (54th year Landtechnik 4/99). As part of this article, as well as in other discussions, the "rainflow" count is explained, which, with available computing power, makes it possible to classify load profiles on a machine component to create a load collective and to calculate machine component damage from this, which per load class - ultimately from the quotient "number of load cycles to be endured" (from the load spectrum) divided by "number of load cycles to be endured" (from a limit characteristic; so-called Wöhler curve) - indicates a damage number or, in the reciprocal value, a measure for a reserve distance to the limit characteristic. By summing up the damage to parts, a degree of damage can be specified for an operationally stable design or, from a distance to the limit characteristic curve, a time interval that limits the running time of the machine component can be specified.

In the present case, it has also proven to be advantageous for the damage number to be determined from the frequency of load class changes and/or the number of load classes, in particular the total number of predetermined load classes, in particular for loads outside of nominal operation and/or extreme loads, on the machine component . The damage number can be specified in particular with at least one ratio, in particular a quotient, on the one hand a frequency of load class changes and/or number of load classes in relation and on the other hand a theoretical limit value on a limit characteristic (exchange characteristic value) which defines a limit -Specifies the frequency and/or limit number for the machine component at which it would probably have to be exchanged based on experience. A preferred embodiment for determining a damage number is in 7 described.

• 1 eine bevorzugte Ausführungsform einer Brennkraftmaschine in einer schematischen Darstellung der Funktionalitäten eines „virtuellen Sensors“ gemäß dem Konzept der Erfindung;
• 2A, 2B zwei Beispiele idealisierter Verläufe einer Abgastemperatur aufgetragen als Temperatur über eine normierte Zeitachse als Beispiel einer Medientemperatur für das Betriebsmedium Abgas, wobei die Medientemperatur als transiente, insbesondere zyklische -im Sinne eines Zyklus zwischen einem oberen und unteren Temperaturniveau--, Betriebsdaten gemessen wird;
• 3A, 3B einen ersten beispielhaften realen Verlauf einer Abgastemperatur und schattiert eine Anzahl von tatsächlich physikalisch gemessenen Bauteiltemperaturen an einem Abgasturboladergehäuse; dies an nicht weniger als acht Orten des Abgasturboladergehäuses (3A) sowie einen zweiten beispielhaften realen Verlauf einer Abgastemperatur und mittels dem „virtuellen Sensor“ einen mit einer zeitabhängigen Exponentialfunktion ermittelten bzw. berechneten Temperaturverlauf des Abgasturboladers als Folge der gemessenen Temperatur des Abgases (3B);
• 4A, 4B eine tatsächlich physikalisch gemessene Bauteiltemperatur als Temperaturanstieg an einem Abgasturboladergehäuse und mittels dem „virtuellen Sensor“ einen mit einer zeitabhängigen Exponentialfunktion ermittelten bzw. berechneten Temperaturverlauf des Abgasturboladers als Folge der gemessenen Temperatur des Abgases, wobei die angegebenen Parameter a, b, c der Exponentialfunktion (4A) sowie die empirisch ermittelten Kennfelder zu den Parametern a, b, c der Exponentialfunktion (4B) beispielhaft dargestellt sind;
• 5A, 5B einen örtlichen Temperaturunterschied an einem Abgasturbolader mit hier dargestellten und so bezeichneten Kennlinien TGH8 an einem ersten Ort und TGH3 an einem zweiten Ort, wobei der erste und zweite Ort über eine gewisse Distanz A getrennt sind, sodass dafür eine Temperaturänderungs-Amplitude bestimmbar ist (5A) sowie eine verallgemeinert dargestellte Klassierung einer solchen Temperaturänderungs-Amplitude in einem zweidimensionalen Diagramm als Grundlage eines Betriebsmusters (5B);
• 6A, 6B zwei beispielhafte Betriebsmuster in Matrixform mit klassierten Temperaturänderungs-Amplituden;
• 7 eine bevorzugte Vorgehensweise zur Ermittlung einer Schädigungszahl als Grundlage zur Ermittlung eines laufzeitbegrenzenden Zeitintervalls des Maschinenbauteils;
• 8 einen grundsätzlichen Ablaufplan eines Verfahrens zum Betrieb einer Brennkraftmaschine mit einem Maschinenbauteil das laufzeitbegrenzend für den Betrieb derselben ist.

Embodiments of the invention are now described below with reference to the drawing in comparison to the prior art, some of which is also shown. This is not necessarily intended to represent the embodiments to scale, rather the drawing is in schematic and/or slightly distorted form where it is useful for explanation. With regard to additions to the teachings that can be seen directly from the drawing, reference is made to the relevant state of the art. In this context, it must be taken into account that a wide variety of modifications and changes relating to the form and detail of an embodiment can be made without deviating from the general idea of the invention. The features of the invention disclosed in the description, in the drawing and in the claims can be essential both individually and in any combination for the further development of the invention. In addition, all combinations of at least two of the features disclosed in the description, the drawing and/or the claims fall within the scope of the invention. The general idea of the invention is not limited to the exact form or detail of the preferred embodiment shown and described below, or limited to any subject matter which would be limited compared to the subject matter claimed in the claims. In the case of specified design ranges, values lying within the specified limits should also be disclosed as limit values and be usable and stressable as desired. Further advantages, features and details of the invention result from the following description of the preferred embodiments and based on the drawing; this shows in:

• 1 a preferred embodiment of an internal combustion engine in a schematic representation of the functionalities of a "virtual sensor" according to the concept of the invention;
• 2A , 2 B two examples of idealized curves of an exhaust gas temperature plotted as a temperature over a normalized time axis as an example of a medium temperature for the operating medium exhaust gas, the medium temperature being measured as transient, in particular cyclical - in the sense of a cycle between an upper and lower temperature level - operating data;
• 3A , 3B a first exemplary real course of an exhaust gas temperature and shaded a number of actually physically measured component temperatures on an exhaust gas turbocharger housing; this at no fewer than eight locations of the exhaust gas turbocharger housing ( 3A) as well as a second exemplary real course of an exhaust gas temperature and by means of the “virtual sensor” a temperature course of the exhaust gas turbocharger determined or calculated with a time-dependent exponential function as a result of the measured temperature of the exhaust gas ( 3B) ;
• 4A , 4B an actually physically measured component temperature as a temperature increase on an exhaust gas turbocharger housing and by means of the "virtual sensor" a temperature profile of the exhaust gas turbocharger determined or calculated with a time-dependent exponential function as a result of the measured temperature of the exhaust gas, with the specified parameters a, b, c of the exponential function ( 4A) as well as the empirically determined maps for the parameters a, b, c of the exponential function ( 4B) are exemplified;
• 5A , 5B a local temperature difference on an exhaust gas turbocharger with characteristic curves TGH8 shown here and designated as such at a first location and TGH3 at a second location, the first and second locations being separated by a certain distance A, so that a temperature change amplitude can be determined for this ( 5A) as well as a generalized classification of such a temperature change amplitude in a two-dimensional diagram as the basis of an operating pattern ( 5B) ;
• 6A , 6B two exemplary operating patterns in matrix form with classified temperature change amplitudes;
• 7 a preferred procedure for determining a damage number as a basis for determining a runtime-limiting time interval of the machine component;
• 8th a basic flowchart of a method for operating an internal combustion engine with a machine component that limits the running time for the operation of the same.

The transient operation of an internal combustion engine 1 causes a transient, in particular mostly cyclic heating and cooling of the engine and other components thereof; for example in terms of a cycle between an upper and lower temperature level. These processes of an internal combustion engine 1 are symbolically represented for some components such as a motor M, an exhaust gas turbocharger AGT, a heat exchanger WT and an exhaust pipe with exhaust gas aftertreatment unit AG in 1 shown. The associated transient or cyclical temperature curves T_M, T_AGT, T_WT, T_AG, which can be determined within the scope of the concept of the invention by means of a “virtual sensor”, for these components or their machine parts are in 1 also shown in block 1'.

The number and extent, in particular size or amplitude, of the temperature differences or temperature gradients of these transient temperature profiles or cycles ultimately determine the service life of the components mentioned here as examples, since they ultimately result in a load change for the components or their machine parts and an associated cause thermal fatigue of the components or their machine parts.

So far, the temperature curves T_i (i=M, AGT, WT, AG) symbolically shown in block 1' have not been recorded continuously either by parts of the internal combustion engine or by the components shown here in particular or their machine parts. At best, media temperatures are recorded, ie temperatures T_j of the coolant KM, lubricants such as oils SS, the fuels KS and the charge air LL or exhaust gas temperatures AG (j=KM, SS, KS, LL, AG). These media temperatures of the operating media assigned to the aforementioned components are also shown symbolically in block 1" in the internal combustion engine 1; namely measured in real terms in the engine or its cylinder head, for example for the charge air, or in the exhaust gas turbocharger for the charge air and exhaust gas quantity, or in the heat exchanger for the coolant KM or at the exhaust aftertreatment or an exhaust pipe for the exhaust gas AG. Corresponding temperature curves T_j (j=KM, SS, KS, LL, AG) for the operating media are in block 1" of 1 also represented symbolically.

The operating medium temperatures T_j (j=KM, SS, KS, LL; AG) that are generally available in this way and mostly at least partially their transient curves do not provide any information about the load on the motor M or other components of the internal combustion engine 1 as such. At most, they provide statements relating to fundamental deviations from normal operation of the internal combustion engine; for example, a statement such that the cooling water temperature for the engine is increased and the engine M is either running outside of normal operation or the cooling is problematic. Thus, a possible degree of damage due to thermal fatigue, at least of the components of an internal combustion engine, and thus the degree of wear caused by thermal fatigue is fundamentally unknown to date - neither in terms of the result nor in its transient course.

As a result, damage and damage that actually occurs in an internal combustion engine 1 in the field can neither be anticipated nor reproduced in detail—i.e. H. As a result, there is still a comparatively high risk potential that an internal combustion engine will fail unexpectedly. In the vast majority of cases, this is associated with a high risk for the vehicle in which the internal combustion engine is installed—for example, in the case of a ship with a ship engine or the like.

Therefore, the concept of the invention within the scope of in 1 The "virtual sensor" shown is a calculation model and a method that, in contrast to previous approaches for specifying runtime-limiting time intervals of a machine component, can be substantiated and also adapted or is more reliable from the outset than previous approaches.

Previous calculations, such as strength calculations of the type mentioned at the outset, are in part very imprecise and must therefore be carried out extremely conservatively in order to define preventive maintenance and replacement intervals for engine components that are usually too short. This state of affairs causes comparatively high life cycle costs and leads to a reduction in competitiveness.

The concept of the invention has recognized that a thermal load on machine components of the internal combustion engine can only be reliably assessed if the medium temperatures, for example the aforementioned medium temperatures of the charge air LL, the exhaust gas AG, the coolant KM and the like are not only monitored, but also their transient curves T_j (j=KM, SS, KS, LL; AG) can be specifically recorded and saved.

For this purpose, a drive system 100 looks like it is in 1 an internal combustion engine 1 is shown with a control and regulating device ECU known per se and a sensor system S also known per se which is able to at least monitor the operation of the internal combustion engine 1 via the sensor system S by means of a detection device EE.

Operating data of the internal combustion engine 1 and the operating media, ie here the coolant KM, lubricants such as oils SS, the fuels KS and the charge air LL or exhaust gas temperatures AG as under 1 'in 1 are shown, ie in particular the transient temperature profiles T_j (j=KM, SS, KS, LL; AG) in block 1" of the operating media are now specifically recorded and stored according to the concept of the invention in the detection device EE. In real operation So far, no component temperatures and certainly no temperature changes or gradients in transient operation for an internal combustion engine have been recorded. The component temperature and its damaging temperature differences or temperature gradients due to warming-up processes can at best be inferred from other sensor values such as the exhaust gas temperature. Of course, such approaches cannot take into account the transient Simulate operation and the associated actual load curves of the machine component.

According to the concept of the invention, the aforementioned media temperature below block 1" is not to be equated with the component temperature below block 1' - the concept of the invention also provides for an evaluation unit AE and/or a remote unit RE that work together with the ECU Evaluation unit AE with the detection device EE, possibly in a data-technical connection with the remote unit RE and/or the ECU, provide the functionality of the "virtual sensor" VS by means of the transient or cyclic temperature profiles T_M, T_AGT, T_WT, T_AG for the above-mentioned components or their machine parts of the internal combustion engine 1 according to block 1' are determined without having to measure them in a complex manner using a real sensor system with the disadvantages mentioned at the outset.

While previously based on sensor values from physically present sensors of the plant The concept of the invention has recognized that the sensor system S described here with the “virtual sensor” VS has considerable advantages over known, physically existing sensor models. If other or additional values are of interest in physically existing sensor systems, additional sensors usually have to be retrofitted. This makes the system more expensive and at the same time reduces its reliability. The method according to the concept of the invention manages without these physical sensors and thus generates no, or only marginal, additional costs.

• - Betriebsdaten T_M, T_AGT, T_WT, T AG eines Maschinenbauteil -wie etwa Motor M, einem Abgasturbolader AGT, einem Wärmetauscher WT sowie einer Abgasleitung mit Abgasnachbehandlungsaggregat AG-- zu bestimmen, indem diejenigen Betriebsdaten ermittelt werden, die in einem Wirkzusammenhang mit einem, insbesondere tatsächlichen, Lastverlauf des Maschinenbauteils stehen, wobei diese Betriebsdaten wenigstens eine Medientemperatur T_j (j=KM, SS, KS, LL; AG) eines der Betriebsmedien KM, SS, KS, LL; AG umfassen, und
• - die wenigstens eine Medientemperatur T_j (j=KM, SS, KS, LL; AG) als transiente, insbesondere zyklische, Betriebsdaten gemessen wird.

The "virtual sensor" VS is designed

• - To determine operating data T_M, T_AGT, T_WT, T AG of a machine component - such as engine M, an exhaust gas turbocharger AGT, a heat exchanger WT and an exhaust pipe with exhaust gas aftertreatment unit AG - by determining those operating data that are in an effective connection with a, in particular actual load profile of the machine component, these operating data being at least one media temperature T_j (j=KM, SS, KS, LL; AG) of one of the operating media KM, SS, KS, LL; AG include, and
• - The at least one medium temperature T_j (j=KM, SS, KS, LL; AG) is measured as transient, in particular cyclic, operating data.

Furthermore, according to the concept of the invention, it is provided within the framework of the evaluation unit AE or remote unit RE that the mentioned causal relationship is represented by means of an algorithm such that a machine component temperature T_M, T_AGT, T_WT, T_AG is transiently determined as in block 1' from the transient medium temperature as in block 1". The concept of the invention thus includes the creation and application of algorithms with the help of which the machine component temperature T_M, T_AGT, T_WT, T_AG is determined on the basis of the medium temperature - this is also referred to below as the functionality of the " virtual sensor” VS.

Furthermore, the evaluation unit AE or the remote unit RE is designed to indicate at least one temperature change in the machine component temperature--in particular a temperature change amplitude of the machine component temperature-- using the transient machine component temperature T_M, T_AGT, T_WT, T_AG as shown in block 1' and to be classified as the basis of an operating pattern characterizing the operation of the machine component.

It has been shown that the detected temperature changes or temperature gradients within the aforementioned engine components can provide information about the transient operation and the load or strength limit of the components, for example with the help of a modern representative of a stochastic evaluation, namely the rainflow counting method. As a result, the thermal load changes of different magnitudes are stored in an operating pattern - the magnitudes can be defined as required within the framework of the classification. The operating pattern can then form the basis for the exact calculation of the transient load or strength limits. On the basis of the operating pattern, the time interval that limits the running time of the internal combustion engine can therefore be specified for the operation of the internal combustion engine. In this way, the preventive exchange or overhaul interval for this construction machine component can be defined depending on the load profile or operating pattern.

Such a concept leads to a comparatively intelligent maintenance concept with optimization of the design methods in analysis and the formation of forecast models. Due to advances in IT technologies, the operating data of a system can be precisely recorded and evaluated during real operation. This is achieved by the sensors, the registration unit EE and the evaluation unit AE/RU, i. H. the data can either be evaluated and stored locally on an "on-board unit" AE or sent to a server for more detailed analyzes such as the RE. Thus, the operating data are increasingly included for the assessment of the functionality and the resilience of the technical systems.

The present concept of the invention is explained step by step in the following using graphics, which ultimately results in a very realistic and proven reliable virtual sensory detection of a transient machine component temperature as shown in FIG. 1′.

2A shows a course of an exhaust gas temperature 1''_AG plotted as temperature over a normalized time axis. In some places, this shows extreme reversal areas U1 and U2, which due to their different temperature levels - with U1 around 200°C or 600°C and U2 around 300°C and 400°C -- can be assigned to a cyclic load change are. That means the "load change 1" in 2A is completed with an inertia time in the temperature extremes of min/max 200°C/600°C, the "load change 2" in 2A at temperature extremes of min/max 300°C/400°C.

A different temperature profile of the exhaust gas 1''_AG is in 2 B shown with this plotted is as a normalized temperature over a time axis - during 2A i.e. essentially idealized fluctuations in the exhaust gas temperature 1''_AG with persistence times during transient operation 2 B , which does not have to be the same depending on the temperature profile, but can vary greatly.

3A again shows an exhaust gas temperature 1''_AG as a result - this time not idealized, but realistic; the essentially rectangular course can be seen, which per cycle shows a load change with lower and upper extreme points for the machine components subjected to exhaust gas - e.g. B. an exhaust gas turbocharger AGT or an exhaust gas aftertreatment or an exhaust pipe for the exhaust gases AG-- results. The rectangular profile of the exhaust gas temperature 1''_AG has a temperature level in each of the reversal areas, namely at around 50° C. in the lower area and at around 800° C. in the upper area. To demonstrate the realistic sequence of such load changes, 3A shaded shows a number of actually physically measured component temperatures on an exhaust gas turbocharger housing TGH at no fewer than 8 locations, which are numbered consecutively with T_TGH_i (i=1..8) - all these temperature advances T_TGH_i (i=1..8) on the machine component of an exhaust gas turbocharger are of a transient nature and can be represented by an exponential function. Ultimately, this confirms the principles of heat and mass transfer theory.

3B shows again a measured curve of an exhaust gas temperature 1 ''_ AG with a now simulated machine component temperature T_AGT - in this case T_TGH_8 (i = 8) - ie with a time-dependent exponential function calculated according to the concept of the invention calculated temperature curve of the exhaust gas turbocharger as a result of the measured Temperature of the exhaust gas 1''_AG.

• a - der maximale Temperaturanstieg des Bauteils bei einem Temperaturursprung des Abgases
• b - definiert die Steigung des Temperaturverlaufs
• c - Anfangstemperatur des Bauteils entsprechend der Vorgeschichte.

The machine component temperature T_AGT behaves --like 3A and shows-- practically realistic to the measured course. A section for an increasing component temperature is in 4A darkened and marked with T_AGT_M - in this case T_TGH_8 (i=8)--. The representation of the temperature of the exhaust gas turbocharger follows the exponential function T_AGT with three parameters given above the graphic:

• a - the maximum temperature rise of the component at a temperature origin of the exhaust gas
• b - defines the slope of the temperature profile
• c - initial temperature of the component according to the history.

The description of temperature profiles of a component with a time-dependent exponential function, which has proven its worth in heat and mass transfer theory, thus proves to be realistic within the scope of the concept of the invention. The terms of this function can basically be physical quantities that describe the flow properties of the medium such as the temperature of the medium and the mass flow of the medium - environmental conditions and component properties such as the geometry and the material can also be reproduced.

In the present case, the in 4A and 3B shown temperature of the exhaust gas turbocharger T_AGT_M - in this case T_TGH_8 (i=8) or further for i=1..8-- calculated, whereby the in 4A specified parameters a, b, c have been taken from characteristic diagrams or characteristic curve diagrams that have been determined empirically - these are exemplary in 4B shown. In other words, the coefficients for the component of the exhaust gas turbocharger can be stored as a function of the operating point of the internal combustion engine from an empirically determined family of characteristics, for example by operating an exhaust gas turbocharger in a test internal combustion engine; for example in the ECU or the registration unit EE or the remote unit. The exponential function of several components, which can be calculated in a comparatively simple manner and practically in real time, as shown in 1 are shown, can thus be used as the core of the evaluation algorithm for displaying the causal relationship between media temperature and machine component temperature in the evaluation unit AE of the "virtual sensor" VS.

If the machine component temperatures are now transiently known, as shown above for the exhaust gas turbocharger, ie at different times and/or at different locations—ie locally distributed over a specific component—temperature differences or temperature gradients can naturally be determined from them. That is to say at a first and a second point in time and/or locally at a first and a second component location. Such temporal and/or local temperature changes can be recorded and - preferably via the temperature change amplitude determined from the machine component temperature (e.g. based on the temperature levels as shown in 2A , 2 B are shown)-classify. In any case, the classification includes ordering. according to size, whereby different sizes can be assigned to a load class. Such a load class can be used as the basis for a Machine component identified operating pattern are determined.

5A shows, for example, in a first modification of the concept of the invention, a local temperature difference on an exhaust gas turbocharger with locations shown here for determining the temperature of the exhaust gas turbocharger T_AGT_M -- in this case T_TGH_8 (i=3.8), ie TGH 8 and TGH 3-- the first and second locations shown here are a certain spatial distance A apart. This would therefore correspond to a local temperature change amplitude or a gradient on the exhaust gas turbocharger. This temperature change amplitude or the gradient causes stresses in the exhaust gas turbocharger; leads to a certain fatigue - a "local" load class can be specified for this depending on the temperature change amplitude or the gradient.

5B shows the representation of this result in a two-dimensional diagram in which the values for a temperature of the exhaust gas turbocharger T_AGT_M can be entered at two locations according to the coordinate axes as TGH 8 and TGH 3 - for such a diagram a limit characteristic GK can be formed, beyond which a Temperature difference or temperature gradient is assumed as the class boundary. In case of 5B the marked point GP indicates a temperature load change with the arrow depicting a load change due to the temperature change at TGH 8, with TGH 3 maintaining a temperature of 200°C - this would be a load change that goes to the limit characteristic GK; i.e. between a class with lower temperature changes and a class with higher temperature changes, according to which a component replacement can be advisable.

6A and 6B now show an operating pattern of the exhaust gas turbocharger in which a large number of classes are drawn.

The matrix LCF of 6A basically classifies the load factors of the engine of an internal combustion engine via engine speed nMOT and engine torque MM relative to one another - the number of load changes is entered for each class; ie operation of the engine leading into and out of a certain class.

The matrix TMF of 6B classifies temperature change amplitudes of a machine component temperature. This can affect local gradients, for example, as shown, relative to one another, a temperature change amplitude of the temperature of the exhaust gas turbocharger T_AGT_M at two locations according to the coordinate axes as TGH j (j=2..8) in relation to TGH 1 - for each class the number of load changes is entered; ie operation of the engine leading into and out of a certain class.

From the synopsis or correlation of the load frequencies per class entered in the matrices LCF and TMF, an operating pattern of the machine component in relation to an operating pattern of the engine can be specified and, based on the operating pattern, a time interval of the machine component that limits the running time for the operation of the internal combustion engine can be determined specify. A total number of predetermined load classes, in particular for loads outside of nominal operation and/or extreme loads, can be determined for the operation of the machine component, such that an operating pattern of the machine component is specified using the total number of predetermined load classes.

In 6B is z. B. from the function of frequency f (nMOT, MM) as a function of engine speed nMOT and engine torque MM, it can be seen that the engine is often operated in the lower speed and torque range, but in correlation thereto 6B -- the exhaust gas turbocharger AGT is often loaded with comparatively high local temperature gradients.

In the 6B The classes shown on the top right represent extreme loads (i.e. loads in principle outside of the rated operation and/or extreme loads of the engine) and the exhaust gas turbocharger shown here was obviously operated in such correlating extreme points. By means of a number of load classes and/or load class changes, as explained in this example, an operating pattern of the machine component can be specified, taking into account the operating pattern of the engine, and the operating time-limiting time interval of the machine component for the operation of the internal combustion engine can be specified on the basis of the operating pattern.

In principle, a matrix can also specify the frequency with which a temporal temperature change amplitude was run through at a location during operation.

7 in a second modification of the concept of the invention, now shows a possibility for determining a runtime-limiting time interval of the machine component; namely there is the amplitude of a temperature change as it was determined for a machine component - in terms of time 2 or locally according to 5 -- plotted against the number of temperature load changes.

The falling curve of the limit characteristic GK represents a theoretical representation of limit points GP of load changes should result in massive damage and thus the replacement of the machine component. In other words, the ratio ni to Ni is decisive for the damage number D_i. If this damage number D_i or total damage D > 1, the damage to the component could be comparatively far advanced and the component should be replaced or it is very likely that it fails. The falling curve of the limit characteristic GK results from a level of temperature change amplitude that is still tolerable in the limit case and the frequency that is still tolerable in the limit case for the loading of the machine component. In other words, the greater the amplitude of the temperature change, the lower the number of times it can be reached before the component is replaced (this represents the ratio n1 to N1 at ΔT1=400°C). On the other hand, if the amplitude is small, it can occur more frequently without the component tiring and the component would only have to be replaced at very high frequency rates (this represents the ratio n2 to N2 at ΔT2=200°C). The number of damage determined in this way is also explained with a theoretical background in the article mentioned at the beginning.

In the present case, a total damage number can be determined for the component by adding up the quotient D_i=n_i/N_i. The bold bars in the diagram characterize the temperature load change reserves Ri=(Ni-ni)/Ni., where Ri+Di=1 applies.

8th shows a basic course of a method for operating an internal combustion engine with a machine component that limits the running time for the operation of the same and a number of operating media that are used to operate the internal combustion engine, with operating data of the internal combustion engine and the operating media being determined and, as a result, a running time limiting time interval of the machine component is specified or recommendation to replace the machine component.

According to the concept of the invention, operating data of the machine component are first determined in step S1, in that those operating data - here a T7 exhaust gas temperature - are determined which are functionally related to the actual load profile of the machine component, with these operating data at least one media temperature of one of the operating media - here an exhaust gas-- comprise; this can also relate to measuring a coolant or charge air temperature, for example.

The at least one medium temperature is measured as transient, in particular cyclical, operating data in step S1.

The functional relationship is represented by means of an algorithm such that a machine component temperature is transiently determined from the transient media temperature—this is implemented in step S2 with the algorithm explained above; ie a virtual temperature T of the machine component is measured as the result of a virtual sensor VS, that is to say in particular it is specified, for example, using an empirical equation, as is shown with reference to FIG 2 until 4 is explained.

In step S3, at least one temperature change in the machine component temperature, in particular the amplitude of the temperature change in the machine component temperature, can be specified using the transient machine component temperature and classified as the basis of an operating pattern identified during operation of the machine component; like this based 5 until 6 is explained. Depending on how many classes are run through during operation of the internal combustion engine, these can be determined as load changes and the number of these in step S4 can be determined in 6B or 6A matrix shown can be stored - ie as count rate per class. For classification according to temperature (matrix TMF in 6B) also a classification of the loads of the internal combustion engine (Matrix LCF in 6A) to be added, in particular to be taken into account and/or correlated.

In step S5, an evaluation is carried out and the frequency or number of times per class is read out with which this class was operated or the distance Ri measured in the x-direction (horizontally) to the temperature reserve, ie the limit curve GK, which is shown in 7 is shown; a selection is therefore made on the basis of the temperature reserve calculated from classification KL (per class, the frequency or number with which this class was operated).

A damage number can thus be calculated in step S6 from the ratio, which expresses the damage number Di or D, which, as long as it is less than 1, leads to the aforementioned steps being repeated more frequently. However, if the damage number Di or D is greater than 1, a recommendation to replace the component can be made in step S7.

If the component has been exchanged, the matrix can be set to 0 in step S8 and the process can begin again.

In step S9, these measures can be implemented for all relevant machine components, ie in particular components of an internal combustion engine - the sum of these gives an overall damage rate of the internal combustion engine and in this respect also leads to an indication of a runtime-limiting interval for the operation of the internal combustion engine as a whole.

Reference List

100

drive system

1

internal combustion engine

M

engine

AGT

exhaust gas turbocharger

WT

heat exchanger

Inc

Exhaust line with exhaust aftertreatment unit

T

temperature curves

KM

cooling medium

Inc

exhaust gases

LL

charge air

S

sensors

EE

detection device

AE

evaluation unit

RU

remote unit

U1, U2

reversal areas

A

distance

D, Tue

damage number

ss

lubricants

KS

fuels

vs

virtual sensor

nMOT

engine speed

mm

engine torque

S1...S9

steps

Lw

load change

cl

classification

TMF

temperature classification

TCF

load classification

Claims (16)

Method for operating an internal combustion engine with a motor and a further component, the internal combustion engine having: - a machine component that can limit the running time for the operation of the internal combustion engine, - a number of operating media that are used to operate the internal combustion engine, namely for operation of the engine and. are supplied to, removed from or kept in the further component, - a device which is designed to at least monitor the operation of the internal combustion engine, wherein in the method: - operating data of the internal combustion engine and the operating media are determined, and - for the operation of the internal combustion engine a time interval of the machine component that limits the running time is specified, namely a time interval until the next maintenance of the internal combustion engine, - operating data of the machine component are determined by determining those operating data that are in an effective connection with an actual load profile of the machine component, whereby these operating data include at least one media temperature of one of the operating media, and - the at least one media temperature is measured as transient operating data, - the functional relationship is represented by means of a calculation or data specification such that a machine component tempera tur transient is determined from the transient medium temperature, the transient machine component temperature being determined at at least a first and/or a second component location and a temporal and/or local temperature change for the component being specified therefrom, characterized in that - by means of the transient machine component temperature at least one temperature change amplitude of the machine component temperature is specified and classified as the basis of an operating pattern characterizing the operation of the machine component, namely a number of load classes for the operation of the machine component is determined, and - by means of a number of load classes and/or load class changes an operating pattern of the machine component is specified, - on the basis of the operating pattern, the time interval limiting the running time of the machine component for the operation of the internal combustion engine is specified. procedure after claim 1 , characterized in that the operating media are an exhaust gas, a charge air, a fuel, a lubricant or a coolant. procedure after claim 1 or 2 , characterized in that the transient medium temperature is examined for a persistence time at a temperature level and at least a presence of the persistence time at a temperature level on a load change for the machine component and one of the following temperature changes in the machine component temperature is inferred. Method according to one of the preceding claims, characterized in that the machine component temperature as a time-dependent curve for the machine component. procedure after claim 4 , characterized in that the time-dependent course for the machine component at a single location and/or at a number of locations of the machine component, is determined using principles of heat and mass transfer theory as a time-dependent exponential function, the time-dependent exponential function being parameters for an initial temperature, a maximum temperature rise and an increase in the temperature profile on the machine component. Method according to one of the preceding claims, characterized in that parameters of the time-dependent profile of the temperature of the machine component are established empirically and/or based on a model. Method according to one of the preceding claims, characterized in that a transient machine component temperature is determined at at least a first and a second point in time and from this a temporal temperature change is specified at at least one component location and a temperature change amplitude is classified such that the temporal temperature change a temporal load class is determined as the basis of an operating pattern characterizing the operation of the machine component. Method according to one of the preceding claims, characterized in that the transient machine component temperature is determined at at least a first and a second component location at least at one point in time and from this a local temperature change amplitude for the component is specified and classified such that from the local Temperature change, a local load class is determined as the basis of an operating pattern that characterizes the operation of the machine component. Method according to one of the preceding claims, characterized in that a load class is determined from the temporal and/or local temperature change and/or a temperature change amplitude as the basis of an operating pattern characterizing the operation of the machine component. Method according to one of the preceding claims, characterized in that a frequency of load class changes is specified using the operating pattern of the machine component and the number of load class changes specifies the time interval of the internal combustion engine that limits the running time. Method according to one of the preceding claims, characterized in that a total number of predetermined load classes, namely for loads outside of the rated operation and / or extreme loads, for the operation of the machine component is determined such that by means of the total number of predetermined load classes Operating model of the machine component is specified. Method according to one of the preceding claims, characterized in that the time interval of the internal combustion engine that limits the running time is determined from a damage number, the damage number being determined from the frequency of load class changes and/or the number of load classes. procedure after claim 12 , characterized in that the damage number from the total number of predetermined load classes on the machine component, the damage number indicating at least one ratio of the frequency of the load class change and/or number of load classes in relation to an exchange characteristic value of the frequency and /or Number for the machine part. Control device for an internal combustion engine for carrying out a method according to one of Claims 1 until 13 , comprising - a monitoring device that is designed to at least monitor the operation of the internal combustion engine, - a detection device using the operating data of the internal combustion engine and the operating media are determined, wherein - a determining device using the time interval of the machine component that limits the running time for the operation of the internal combustion engine is specified, namely a time interval until the next maintenance of the internal combustion engine, with the control device being designed in such a way - to determine operating data of the machine component by determining those operating data which are functionally related to an actual load profile of the machine component, with this operating data at least include a media temperature of one of the operating media, and - the at least one media temperature is measured as transient operating data, - the causal relationship is represented by means of a calculation or data specification is such that a machine component temperature transient is determined from the transient medium temperature ture, wherein the transient machine component temperature is determined at at least a first and/or a second component location and a temporal and/or local temperature change for the component is specified therefrom, characterized in that - by means of the transient machine component temperature at least one temperature change amplitude of the machine component temperature is specified and classified as the basis of an operating pattern characterizing the operation of the machine component, namely a number of load classes for the operation of the machine component is determined, and - an operating pattern of the machine component is specified by means of a number of load classes and/or load class changes, - Based on the operating pattern, the time interval limiting the running time of the machine component for the operation of the internal combustion engine is specified. control device Claim 14 , characterized in that an evaluation device is movable with the internal combustion engine in a vehicle or arranged separately from it at a fixed location, by means of which classification is carried out, an operating pattern is specified and a time interval of the machine component limiting the running time is specified for the operation of the internal combustion engine. Internal combustion engine with a control device Claim 14 or 15 with a motor and a further component, wherein - the internal combustion engine is designed for operation with a number of operating media that are used to operate the internal combustion engine, namely the engine and. to which other components are supplied, removed or kept in them, and has: - a machine component that can limit the running time for the operation of the internal combustion engine, - a monitoring device that is designed to at least monitor the operation of the internal combustion engine, - a detection device by means of the operating data of the internal combustion engine and the operating media are determined, with - a determination device by means of which a time interval limiting the running time of the machine component is specified for the operation of the internal combustion engine, namely a time interval until the next maintenance of the internal combustion engine, the control device being designed in such a way - To determine the operating data of the machine component by determining those operating data that are in an effective connection with an actual load profile of the machine component, these operating data at least one medium temperature of one of the operating med ien, and - the at least one medium temperature is measured as transient operating data, - the functional relationship is represented by means of a calculation or data specification such that a transient machine component temperature is determined from the transient medium temperature, with the transient machine component temperature being at least one first and/or a second component location is determined and from this a temporal and/or local temperature change for the component is specified, characterized in that - at least one temperature change amplitude of the machine component temperature is specified by means of the transient machine component temperature and as the basis of a den Operation of the machine component characteristic operating pattern is classified, namely a number of load classes for the operation of the machine component is determined, and - specified by a number of load classes and / or load class change an operating pattern of the machine component - on the basis of the operating pattern, the time interval limiting the running time of the machine component for the operation of the internal combustion engine is specified.

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