DE102018204697A1 - A method for generating a value, wherein the value allows a conclusion to a temperature of a coolant - Google Patents

Abstract

A method for generating a value, wherein the value allows a conclusion to a temperature (1) of a coolant (2); wherein the coolant (2) is used to control the temperature of a drive unit (4), wherein the drive unit (4) is operable at different operating points (5, 6), wherein for at least two operating points (5, 6) different setpoint temperatures (7, 8 ) are predetermined for the coolant (2); wherein the temperature display device (3) represents a value (9) for the temperature (1) representing at least one deviation (10, 11) of a determined coolant temperature (12) from the changing target temperature (7, 8).

Description

The invention relates to a method for generating a value, wherein the value allows a conclusion to a temperature of a coolant. The value can be used to represent a temperature of a coolant in a temperature display device, wherein the coolant is used for temperature control of a drive unit. The drive unit is in particular a drive unit of a motor vehicle, for. As an internal combustion engine, an electric drive or the like. The temperature display device serves, in particular, to visualize the temperature of the coolant for a user of the motor vehicle.

The display strategy for the coolant temperature z. B. in a combination instrument of a motor vehicle is in modern engines generally a challenge because they have operating point-dependent set temperatures for the coolant, which can be up to 25 degrees Celsius apart. Furthermore, thermal overshoots in the coolant temperature control also occur in classic engines with a single setpoint temperature. The unfiltered display of these changes in temperature could mislead the user of the motor vehicle to suspect malfunction of the engine, so that unnecessary visits to the workshop would be expected.

However, the temperature display device should be able to point to engine temperatures that are outside the control temperatures, so that the user of the motor vehicle, a possible overheating of the engine can be displayed.

From the DE 10 2017 001 250 A1 is z. B. known that the determined (and actually present) coolant temperature is adjusted in a control unit by a characteristic. This characteristic ensures that an actual coolant temperature between 75 and 110 degrees Celsius is displayed as being approximately constant at 90 degrees Celsius. In the ranges colder than 75 degrees Celsius and warmer than 110 degrees Celsius then not the actual coolant temperature, but also indicated by the characteristic curve temperature is displayed, in which case the change in the indicated temperature is again greater than the change in the actual coolant temperature.

This adaptation of the displayed temperature by a characteristic results in that when changing the coolant temperature of z. For example, from 110 to 115 degrees Celsius, the displayed temperature changes from 90 to 115 degrees Celsius in a very short time. A user might get the impression that the temperature gauge is faulty or the engine is boiling down.

The introduction of modern engines having operating point-dependent desired temperatures for the coolant can be countered by the use of characteristic curves which set a fixed (or very little changing) displayed temperature over an even greater temperature interval of the coolant temperature.

A correct representation of the coolant temperature then does not take place.

The object of the present invention is at least partially to solve the problems mentioned with reference to the prior art. In particular, a method for generating a value should be proposed, wherein the value can be used to represent a temperature of a coolant. The method should allow a more accurate representation of a determined coolant temperature. Preferably, the representation of the coolant temperature should be comprehensible for the user.

To solve these problems, a method with the features according to claim 1 contributes. Advantageous developments are the subject of the dependent claims. The features listed individually in the claims can be combined in a technologically meaningful manner and can be supplemented by explanatory facts from the description and / or details of the figures, with further embodiments of the invention are shown.

A method is proposed for generating a value, wherein the value allows a conclusion to a temperature of a coolant. In particular, the value may represent a temperature of a coolant in a temperature display device. The coolant is used for temperature control of a drive unit. The drive unit is operable in different (different from each other) operating points, wherein different setpoint temperatures for the coolant are predetermined for at least two operating points. The value represents at least one deviation of a determined coolant temperature from the (changing or from the respectively current) setpoint temperature.

With a temperature display device, the value for the temperature can be displayed.

The drive unit is in particular a drive unit of a motor vehicle, for. As an internal combustion engine, an electric drive or the like. The temperature display device is used in particular for the visualization of Temperature of the coolant for a user of the motor vehicle.

The coolant is z. As water or an oil that is used to cool the drive unit. The drive unit is in particular regulated so that different setpoint temperatures for the coolant are predetermined at different operating points of the drive unit. These set temperatures can be z. B. by at least 5 degrees Celsius, in particular by at least 10 degrees Celsius, preferably differ by at least 20 degrees Celsius.

The respective setpoint temperature is predetermined in particular by a control device for each drive unit or each motor vehicle. Thus, set temperatures for certain driving situations (eg sailing, immediately after a cold start, continuous high load of the engine, etc.) can be specified. This is done by z. B. a control unit tries to regulate the coolant temperature as possible to the respective target temperature. Accordingly, the control unit, coolant pumps, heat exchangers and radiators of the motor vehicle are integrated or acted upon.

The generated value (which can be represented, for example, in a temperature display device) represents, in particular, at least one deviation of a determined coolant temperature (for example calculated by a sensor or by a control unit) from the changing target temperature.

In particular, therefore, the value (and thus in a temperature display device) takes into account the changing setpoint temperature, but the change in the setpoint temperature is preferably not reproduced (or displayed in the temperature display device).

In particular, it is proposed that the value represents at least the deviation of the coolant temperature from the target temperature. This can be a user z. B. of the motor vehicle even with varying set temperatures (eg., With a temperature display device) are clearly displayed, whether the coolant temperature is within the permissible range or z. B. overheating may be present.

In particular, the value is composed of the deviation and the determined coolant temperature. For example, the value may be at a higher setpoint temperature (eg, the highest intended setpoint temperature) and a deviation of z. B. 5 degrees Celsius have a higher amount than the value at a lower target temperature (eg., The lowest intended target temperature) and a deviation of 5 degrees Celsius.

This could take into account the fact that at the highest setpoint temperature, an inadmissibly high coolant temperature can be expected faster than at the lowest setpoint temperature. A correspondingly higher value (shown) can sensitize the user for this condition of the motor vehicle.

Preferably, the deviation with a first weighting factor and the determined coolant temperature with a second weighting factor can be taken into account by the value. The weighting factors are different from each other in particular. Due to different weighting factors, the change of one parameter of deviation and coolant temperature can be given more consideration than the change of the other parameter.

In particular, the value can be used to take into account further determined component temperatures, each with its own third weighting factors. In particular, z. As engine block temperature, temperatures of heat exchangers, temperature of the exhaust gas, etc., each with its own third weighting factors are taken into account.

In particular, the generated value, starting from the setpoint temperature and up to a small first deviation, may change by a small first measure compared to a setpoint value and a second deviation (greater than the first deviation) by a larger (larger than the first measure) second Change dimension compared to the setpoint.

The setpoint is in particular the value that z. B. the user is displayed when the coolant temperature corresponds to a target temperature and / or is considered admissible.

In particular, the measure is the respective ratio of the difference between the value to the setpoint and the deviation (ie: (setpoint value) / deviation).

In particular, with a small first deviation, the generated value (or its amount) of the temperature may be less than the actual deviation and, in the case of a larger second deviation, the generated value (or its magnitude) correspond to the temperature at least the actual deviation.

In particular, it is proposed to provide a characteristic here, for. B. in a control unit. With the characteristic curve, the different degree of change of the value with respect to a desired value as a function of the respective deviation can be specified. For small deviations only a small (eg disproportionate) change in the value compared to the setpoint value, with larger deviations resulting in a larger (eg disproportionate) change of the value compared to the setpoint value.

The change or generation (and, for example, the representation) of the value can take place with a time delay of at least one second, in particular of at least five seconds, preferably of at least 10 seconds, compared with a time of determination of the coolant temperature.

Preferably, the deviation is averaged over a period of delay.

In particular, it is proposed that the change of the value, e.g. B. depending on at least one of the following parameters, for. As the deviation, the coolant temperature, the present or changing target temperature, the weighting factors, the possibly changing weighting factors, etc., is smoothed. This can be z. B. by an averaging, d. H. it is considered the change of the parameter over time and z. For example, one (eg arithmetic) average value is generated over the period of the delay. This mean value is used to determine the value.

In particular, it is proposed that the value change more strongly as a function of the deviation than as a function of the changing setpoint temperature. In particular, this is taken into account via the weighting factors.

When changing the setpoint temperature, z. B. from a low to a higher setpoint temperature (especially for the same deviation), if necessary, a higher value can be displayed. Thus, the user can be sensitized for the higher coolant temperature.

1. a) Ermittlung der jeweiligen Solltemperatur für den vorliegenden Betriebspunkt;
2. b) Ermittlung der Kühlmitteltemperatur (z. B. durch Messung oder durch rechnerische Bestimmung, ggf. anhand eines Kennfelds);
3. c) Berechnung des Wertes;
4. d) Bereitstellung des Wertes (z. B. für eine Temperaturanzeigevorrichtung).

In particular, the method may comprise at least the following steps:

1. a) determination of the respective setpoint temperature for the present operating point;
2. b) determination of the coolant temperature (eg by measurement or by arithmetical determination, if appropriate by means of a characteristic map);
3. c) calculation of the value;
4. d) providing the value (eg for a temperature indicating device).

Further, a temperature indicating device for displaying a temperature of a refrigerant is proposed. The temperature display device represents the value generated by the method already described.

Furthermore, a use of the value generated by the method already described for a temperature indicating device is proposed.

A computer program is proposed which is set up to carry out the method already described.

A machine-readable storage medium (for example a control device) is proposed on which the computer program already described is stored.

The temperature display device is arranged in particular in a motor vehicle and provided for displaying a coolant temperature.

The storage medium is installed in particular in a motor vehicle.

The explanations regarding the method apply in particular equally to the temperature display device, the computer program, the storage medium and the use; and vice versa.

A motor vehicle with a drive unit (for example an internal combustion engine or an electric drive or the like) for driving the motor vehicle as well as the described temperature indicating device is also proposed.

By way of precaution, it should be noted that the numerical terms used here ("first", "second",...) Primarily (only) serve to distinguish a plurality of similar objects, variables or processes, ie in particular no dependence and / or order of these objects, quantities or mandate processes to one another. If a dependency and / or order are required, this is explicitly stated here or it obviously results for the person skilled in the art when studying the concretely described embodiment.

• 1: ein Kraftfahrzeug in einer Draufsicht;
• 2: zwei Diagramme, in denen eine Kurve der Kühlmitteltemperatur und ein Verlauf des Wertes dargestellt sind;
• 3: zwei weitere Diagramme, in denen eine weitere Kurve der Kühlmitteltemperatur und ein weiterer Verlauf des Wertes dargestellt sind;
• 4: ein Diagramm mit einer Kennlinie zur Bestimmung des Werts in Abhängigkeit von der Abweichung; und
• 5: eine Temperaturanzeigevorrichtung.

The invention and the technical environment will be explained in more detail with reference to the accompanying figures. It should be noted that the invention should not be limited by the stated embodiments. In particular, unless explicitly stated otherwise, it is also possible to extract partial aspects of the facts explained in the figures and to combine them with other components and findings from the present description. In particular, it should be noted that the figures and in particular the illustrated proportions are only schematic. Show it:

• 1 a motor vehicle in a plan view;
• 2 two diagrams showing a curve of the coolant temperature and a course of the value are shown;
• 3 Two further diagrams in which a further curve of the coolant temperature and a further course of the value are shown;
• 4 : a graph with a characteristic curve for determining the value as a function of the deviation; and
• 5 a temperature indicator.

The 1 shows a motor vehicle 20 in a top view. The car 20 has a drive unit 4 on that over a cooling circuit 21 is temperature controlled. In the cooling circuit 21 a coolant flows 2 that is a temperature 1 having. A temperature display device 3 serves to represent a value 9 for the temperature 1 of the coolant 2 , The drive unit can be in a first operating point 5 and at a second operating point 6 operate. A control unit 23 can be a component temperature 15 (here the temperature 1 the drive unit, ie z. As the temperature 1 of the engine block) as well as the coolant temperature 12 to capture. Further, in the control unit weighting factors 13 . 14 . 16 be deposited.

2 shows two diagrams in which a curve of the coolant temperature 12 and a course 22 of value 9 are shown. On the horizontal axis is the time 19 applied. On the vertical axes, on the one hand, the temperature 1 and second, the value 9 applied. The upper diagram shows the curve of the coolant temperature 12 , The coolant temperature 12 is through the control unit 23 regulated, with different set temperatures 7 . 8th depending on the respective operating point 5 . 6 the drive unit 4 are provided. The coolant temperature 12 is regulated so that it is as possible the target temperature 7 . 8th equivalent.

The lower diagram shows the course 22 of value 9 by the temperature indicator 3 is pictured. With the temperature indicator 3 can be a value 9 for the temperature 1 be presented, the at least one deviation 10 . 11 a determined coolant temperature 12 from the changing setpoint temperature 7 . 8th represents.

In the lower diagram, the course reaches 22 of value 9 after a short time 19 the setpoint 25 that a user z. B. a motor vehicle 20 is displayed when the coolant temperature 12 a set temperature 7 . 8th (substantially) complies and / or is considered admissible.

Since here is the coolant temperature 12 the respective setpoint temperature 7 . 8th can be quickly tracked and a significant (ie considered inadmissible) deviation 10 . 11 never exists, the value is 9 each to the setpoint 25 , A noticeable change in the representation of the coolant temperature for the user 12 is not available, the change in the setpoint temperature 7 . 8th is not displayed.

3 shows two more diagrams, in which another curve of the coolant temperature 12 and another course 22 of value 9 are shown. On the comments too 2 will be referred.

The upper diagram shows the curve of the coolant temperature 12 , It is at a time 18 a larger second deviation 11 the coolant temperature 12 from the second setpoint temperature 8th in front. At another time 18 there is a lower first deviation 10 in front. The lower diagram shows the course 22 of value 9 by the temperature indicator 3 is pictured. This is the first deviation 10 not by changing the value 9 considered. The second deviation 11 however leads to a change of the value 9 but with a time delay 17 ,

At the slight first deviation 10 deviates from the value shown 9 by a small first measure 24 (zero here) from the setpoint 25 from. At the larger (greater than the first deviation 10 ) second deviation 11 deviates from the value shown 9 by a larger one (larger than the first dimension 24 ) second measure 26 from the setpoint 25 from.

4 shows a diagram with a characteristic curve to determine the value 9 depending on the deviation 10 . 11 , On the horizontal axis is the deviation 10 . 11 applied. On the vertical axis is the value 9 applied.

With the characteristic the different measure can 24 . 26 the change of value 9 opposite to the setpoint 25 depending on the respective deviation 10 . 11 from the set temperature 7 . 8th be specified. For small first deviations 10 Only a small (eg, under-proportional) change takes place (first measure 24 ) of the value 9 opposite to the setpoint 25 , with larger second deviations 11 a larger (eg disproportionate) change (second measure 26 ) of the value 9 opposite to the setpoint 25 he follows.

According to the characteristic, the value shown becomes 9 starting from the setpoint temperature 25 and to a small first deviation 10 by a small first measure 24 against a setpoint 25 changed and at a larger (greater than the first deviation 10 ) second deviation 11 one larger (larger than the first dimension 24 ) second measure 26 opposite to the setpoint 25 changed.

The measure 24 . 26 Here is the slope of the characteristic, ie the respective ratio of the difference of the value 9 to setpoint 25 and the deviation 10 . 11 (ie: (setpoint - value) / deviation).

5 shows a temperature indicator 3 , The temperature display device 3 has a scale 28 for the values 9 on and a pointer 27 to represent the present value 9 , In one area 29 which is an optimal range for a user 29 for the value 9 or the coolant temperature 12 represents, is the setpoint 25 ,

With the temperature indicator 3 and by the described method, a coolant temperature can be meaningfully displayed, even if the drive unit 4 of the motor vehicle 20 with different set temperatures 7 . 8th for the coolant 2 is operated. When the setpoint temperature changes 7 . 8th there is no automatic change of the displayed value 9 , Rather, only one (impermissible) deviation 10 . 11 from the set temperature 7 . 8th shown.

LIST OF REFERENCE NUMBERS

1

temperature

2

coolant

3

Temperature indicator

4

drive unit

5

first operating point

6

second operating point

7

first set temperature

8th

second setpoint temperature

9

value

10

first deviation

11

second deviation

12

Coolant temperature

13

first weighting factor

14

second weighting factor

15

component temperature

16

third weighting factor

17

delay

18

time

19

Time

20

motor vehicle

21

Cooling circuit

22

course

23

control unit

24

first measure

25

setpoint

26

second measure

27

pointer

28

scale

29

Area

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102017001250 A1 [0004]

Claims (13)

A method for generating a value (9), wherein the value (9) allows a conclusion to a temperature (1) of a coolant (2); wherein the coolant (2) is used to control the temperature of a drive unit (4), wherein the drive unit (4) is operable at different operating points (5, 6), wherein for at least two operating points (5, 6) different setpoint temperatures (7, 8 ) are predetermined for the coolant (2); wherein the value (9) represents at least one deviation (10, 11) of a determined coolant temperature (12) from the setpoint temperature (7, 8). Method (1) according to Claim 1 , wherein the value (9) is composed of the deviation (10, 11) and the determined coolant temperature (12). Method (1) according to Claim 2 wherein the deviation (10, 11) with a first weighting factor (13) and the determined coolant temperature (12) with a second weighting factor (14) are taken into account by the value (9). Method (1) according to Claim 3 , wherein by the value (9) further determined component temperatures (15) are taken into account, each with its own third weighting factors (16). Method according to one of the preceding claims, wherein the value (9) is changed starting from the setpoint temperature (5, 6) and up to a small first deviation (10) by a small first measure (24) compared to a desired value (25) a larger second deviation (11) is changed by a larger second dimension (26) than the desired value (25). Method according to one of the preceding claims, wherein a change in the value (9) with a time delay (17) of at least one second compared to a time (18) of the determination of the coolant temperature (12). Method according to Claim 6 wherein the deviation (10, 11) is averaged over a period of delay (17). Method according to one of the preceding claims, wherein the value (9) in response to the deviation (10, 11) changes more than in dependence on the changing set temperature (7, 8). Method according to one of the preceding claims, wherein the method comprises at least the following steps: a) determination of the setpoint temperature (7, 8) for the present operating point (5, 6); b) determination of the coolant temperature (12); c) calculation of the value (9); d) provision of the value (9). Temperature display device (3) for displaying a temperature (1) of a coolant (2); wherein the temperature indicating device (3) represents the value (9) generated by the method according to any one of the preceding claims. Use of the method according to any one of Claims 1 to 9 generated value (9) for a temperature display device (3). Computer program, which is set up, the method according to one of Claims 1 to 9 perform. Machine-readable storage medium on which the computer program is based Claim 11 is stored.

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