DE102009054814B4 - Method for optimizing thermal management in a motor vehicle - Google Patents

Abstract

Method for optimizing thermal management in a motor vehicle having an internal combustion engine, comprising a warm-up concept according to the principle of the split cooling concept, in which a cooling medium flow is interrupted by a cylinder block during the warm-up phase of the internal combustion engine, the motor vehicle having heating elements comprising receiving at least one input parameter ( X1 ... X18), determining a deviation of the actual amounts of the input parameters (X1 ... X18) from parameter limit values (X12, X13, X14) related to decision criteria (a), b), c), and intervening in the Warm-up concept according to the determined deviation, if there is a heating request from vehicle occupants.

Description

The invention relates to a method for optimizing a thermal management in a motor vehicle with an internal combustion engine, comprising a warm-up concept according to the principle of split cooling concept, in which a cooling medium flow is interrupted during the warm-up phase of the internal combustion engine by a cylinder block, wherein the motor vehicle has heating elements.

The DE 102 34 087 A1 discloses a method for operating a cooling and heating circuit. In this case, a warm-up concept with a first coolant path, ie a bypass, is described in order to influence the warm-up phase of the internal combustion engine. Next discloses the DE 102 34 087 A1 a flow direction reversal of the coolant as a warm-up concept, so that first the head and then the block is flowed through, wherein the block is thus always flowed through in the warm-up phase always with coolant. In a further embodiment, the pump is stopped, so that a heat transfer via the Thermosyphonwirkung is avoided or reduced.

The DE 10 2008 018 562 A1 on the other hand, it deals with an air conditioning system and a method of operating an air conditioning system of the air conditioning system.

The warm-up phase of the internal combustion engine is the phase at which the internal combustion engine is started after a long standstill (cold start) and continues until the internal combustion engine reaches its operating temperature or operating media such. B. the cooling liquid and / or oil have reached a sufficient temperature level. In this respect, the warm-up concept is preferably carried out only for the duration of the warm-up phase.

To improve the warm-up behavior of the internal combustion engine comes as an example warm-up concept increasingly the principle of split-cooling used, ie the distribution of a coolant circuit in a block-side and in at least one cylinder-side coolant circuit. The at least one cylinder head cooling circuit may also be referred to as a first partial circuit, wherein the block cooling circuit may also be referred to as a second partial circuit.

The cylinder-head-side circuit can be subdivided into further subcircuits. In split-cooling systems, during the warm-up phase of the internal combustion engine, the medium flow through the cylinder block (the second partial circuit) is purposefully interrupted by means of a control valve, for example a thermostat, so that coolant does not flow through the block but only through the cylinder head. Is the warm-up phase ended, or reaches z. B. the coolant is a certain temperature level, the block cycle is opened.

Modern engines with a split-cooling concept therefore have at least two engine-internal cooling circuits. The first (cylinder head circuit) is always flowed through and the second (block circuit) connected as needed. As a rule, in the first coolant circuit, a control valve in the embodiment as a conventional wax thermostat, which switches on / off the second cooling circuit and is controlled by means of the cooling water temperature of the first circuit. Coolant circuits according to the split-cooling concept are for example in the EP 1 900 919 A1 and the DE 10 2008 005 231 A1 disclosed.

But also conceivable warming concepts that can influence the cooling circuit of an internal combustion engine with respect to the heat input during the warm-up phase of the internal combustion engine targeted. By way of example, so-called no-flow concepts, regulated water pumps and / or a changed setting with regard to combustion are applicable here, to name just a few examples.

Warm-up concepts is thus based on the primary goal of accelerating the warm-up of the internal combustion engine in the cold phase, whereby more heat is maintained in the internal combustion engine. Conversely, this means that, during the time in which the split-cooling or the warm-up concept works, less heat is the cooling or heating system of the vehicle available. This again counteracts a possible driver request for heating power. In order nevertheless to provide the requested heating power, the driver's request for heating power overrides the split-cooling or warm-up concept, which leads to significantly increased fuel consumption, since the warm-up concept is carried out while at the same time the requested heating power is made available according to the requirements of the vehicle occupant ,

The invention is therefore based on the object to find a method of the type mentioned, which with simple means to achieve a balance between the conflicting requirement, ie the warm-up concept for heating request of the vehicle occupant.

According to the invention the object is achieved by a method having the features of claim 1. The inventive method comprises at least
the inclusion of at least one input parameter,
determining a preferably percentage deviation of the actual amounts of the at least one input parameter from parameter limit values based on decision criteria, and
Intervention in the warm-up concept according to the determined, preferably percentage deviation, if there is a heating request from vehicle occupants.

The determination of the deviation can be made in percent, but can also be made absolutely (map).

• a) ein bedrohliches,
• b) ein sicherheitsrelevantes, oder
• c) ein unangenehmes

In the context of the invention, it is favorable if the parameter limit values relating to decision criteria, which can also be referred to as comfort criteria, are weighted in order to determine whether

• a) a threatening,
• b) a security relevant, or
• c) an unpleasant

Indoor climate is present, the decision criteria are queried successively, the decision criterion b) is queried if the decision criterion a) is negative, that is not present. Similarly, the decision criterion c) is queried if the decision criterion b) is answered in the negative, that is, not present. It is conceivable, of course, first to query the decision criterion b) in order then to query the decision criterion a), whereby a combination query of both decision criteria is also possible.

It is useful if as input parameters, for example, switch positions and positions of functional elements, such. As a heated windscreen, a heated rear window, front and / or rear windscreen wipers, side windows and / or a possible sunroof, and an interior temperature, an outside temperature, a humidity value in the interior, an external moisture, the coolant temperature and / or the oil temperature are recorded. Of course, the input parameters mentioned by way of example may be taken individually and / or in combination with each other, and are not limited to those mentioned. A component temperature (eg in the cylinder head and / or block) is also possible as an input parameter to include a blower position, a position of the air flow, a heating position, an air conditioning setting and / or a recirculating air flap position.

In order to be able to determine whether one of the decision criteria exists, the recorded input parameters are fed to a map block, wherein subsequently it is determined in a decision box whether the decision criterion a) exists, that is, it is determined whether an indoor climate is threatening. If this is the case, the warm-up concept is deactivated, specifically in accordance with the preferred percentage deviation of the actual input parameters from the parameter limit values determined with reference to decision criteria, wherein it is preferably provided to completely deactivate the warm-up concept in such a threatening situation. If it is determined that a threatening indoor climate is not present, ie if the input parameter has not reached the parameter limit value, the decision criterion b) is queried to determine whether a safety-relevant interior climate exists. If this is the case, the warm-up concept is deactivated, specifically in accordance with the preferred percentage deviation of the actual input parameters from the parameter limit values established with reference to decision criteria, wherein it is preferably provided to completely deactivate the warm-up concept in such a safety-relevant situation. If it is determined that a safety-relevant interior climate is not present, ie if the input parameter has not reached the parameter limit value, the decision criterion c) is queried in order to determine whether there is an unpleasant interior climate. If it is confirmed that there is no unpleasant indoor climate, further possible input parameters such. B. The heater switch position, the position of an eco-button switch, as well as the positions of the side windows and / or a roof window a position map block supplied to determine in a subsequent decision block, if there is a clear Heizwunsch. If this is the case, the warm-up concept is deactivated, whereby the heating power is controlled or regulated via the coolant flow and fan. If it is determined that a clear heating request is not available, the warm-up concept remains or is activated.

If it is determined that there is an uncomfortable indoor climate, the indoor temperature, outdoor temperature, and coolant temperature input parameters are applied to a temperature map block to determine in a further decision block whether the coolant temperature is sufficient to provide the requested heating power. If it is confirmed that the coolant temperature is sufficient to provide the requested heating power, the heating power is controlled via the coolant flow in cooperation with fans, whereby the warm-up concept remains activated. If it is determined that the coolant temperature is not sufficiently high, the indoor and outdoor temperature input parameters are fed to another temperature map block to determine in a subsequent decision block, whether the outside temperature has a sufficient amount to the heating power over the according to warm outside air and fan to control or regulate, with the warm-up concept remains activated or will. If it is determined that the outside temperature is not sufficiently high, the procedure is continued with the position map block, the result of the decision being supplied to the decision to determine in the subsequent decision block whether there is a clear heating request. If this is the case, the warm-up concept is deactivated, whereby the heating power is controlled or regulated via the coolant flow and fan. If it is determined that a clear heating request is not available, the warm-up concept remains or is activated.

The invention advantageously achieves a good balance between the two competing requirements (warm-up concept / heating request) in which a corresponding heating-output strategy is carried out.

When starting the engine and during the warm-up phase of the engine, the following parameters are preferably input as input to a calculation model: outside air temperature, humidity (inside / outside), switch position heating and fan and / or air conditioning, cooling water temperature (current & at start), interior temperature (current & at start).

• • Sicherheitsrisiko (z. B. Gefahr von beschlagenden und/oder einfrierenden Scheiben) => Heizleistung geht 100% vor optimalen Kraftstoffverbrauch
• • Überlebensrisiko (z. B. extrem tiefe Innenraumtemperaturen) => Heizleistung geht 100% vor optimalen Kraftstoffverbrauch
• • Kein akuter Heizleistungsbedarf (z. B. wohl temperierte Innenraumtemperatur, warme und/oder heiße Außentemperaturen) => optimalen Kraftstoffverbrauch vor Heizleistung
• • Mischbereiche

From these (or part of) the input parameters, the model determines whether one of the following conditions exists:

• • Safety risk (eg risk of misting and / or freezing windows) => Heating capacity is 100% before optimal fuel consumption
• • Survival risk (eg extremely low interior temperatures) => Heating capacity is 100% before optimal fuel consumption
• • No acute heating power requirement (eg well-tempered interior temperature, warm and / or hot outside temperatures) => optimal fuel consumption before heat output
• • mixing areas

Depending on which case, the control of the split-cooling or warm-up concept 100% is overwritten by the heating output strategy, fully implemented or only partially activated.

It is particularly advantageous in the method that an optimization of the reduction of the fuel consumption depending on the operating and / or environmental conditions, taking into account safety aspects is achievable.

Further advantageous embodiments of the invention are disclosed in the subclaims and the following description of the figures. It shows the only one

1 a flow diagram of the method according to the invention.

1 shows a schematic flow diagram of the method according to the invention 1 ,

The procedure 1 is preferably carried out on an internal combustion engine with a so-called split-cooling concept as an exemplary warm-up concept. In this, the internal combustion engine has a block-side coolant jacket and a cylinder-head-side coolant jacket. Preferably, a control valve in a Wasserauslaßgehäuse, that is connected to the cylinder head, separate component is arranged, wherein the control valve in the preferred embodiment as a thermostat, the total volume flow of the coolant z. B. controls for cooling and heating. The control valve may also be arranged in the cylinder head side coolant jacket. Of course, the control valve may also be arranged at other suitable locations, provided that a flow of coolant through the block-side coolant jacket during a warm-up phase or after a cold start of the internal combustion engine can be prevented. In the block itself, another thermostat may be arranged, which affects the flow of coolant through the block.

• • Überlebensrisiko (z. B. extrem tiefe Innenraumtemperaturen) => Heizleistung geht 100% vor optimalen Kraftstoffverbrauch
• • Sicherheitsrisiko (z. B. Gefahr von beschlagenden und/oder einfrierenden Scheiben) => Heizleistung geht 100% vor optimalen Kraftstoffverbrauch
• • Kein akuter Heizleistungsbedarf (z. B. wohl temperierte Innenraumtemperatur, warme und/oder heiße Außentemperaturen) => optimalen Kraftstoffverbrauch vor Heizleistung
• • Mischbereiche

It is possible that in the warm-up phase of the internal combustion engine, a heating request of the vehicle occupants is requested. From input parameters (or a part thereof), the method or model according to the invention determines whether one of the following conditions exists:

• • Survival risk (eg extremely low interior temperatures) => Heating capacity is 100% before optimal fuel consumption
• • Safety risk (eg risk of misting and / or freezing windows) => Heating capacity is 100% before optimal fuel consumption
• • No acute heating power requirement (eg well-tempered interior temperature, warm and / or hot outside temperatures) => optimal fuel consumption before heat output
• • mixing areas

Depending on which case, the control of the split-cooling or warm-up concept 100% is overwritten by the heating output strategy, fully implemented or only partially activated.

A first map block 2 input parameters are supplied. These are, for example: interior temperature X1, outside temperature X2, humidity interior X3, humidity outside X4, switch position heated windscreen X5, switch position heatable rear window X6, switch position defrost X7, switch position windscreen wiper front X8, switch position windscreen wiper Rear X9, position window X10, position roof window X11. The input parameters X1, X2 and X3 can be assigned as setpoint values X12, X13 and X14 as parameter limits. Of course, is still possible as an input parameter, a coolant temperature X16 and z. B. record an oil temperature, which will be discussed in more detail below. The mentioned input parameters X1 to X11 are, of course, only exemplary, and are not intended to be limiting, whereby further input parameters, such as a component temperature (eg in the cylinder head and / or block), a blower position, a position of the air flow, a Heating position, an air conditioner setting and / or a recirculating air flap position can be used. If the indoor temperature X1 input parameter is not available as a measured value, this can be determined from a model from the input parameter outside temperature X2 together with a value for the heating power. The input parameter humidity interior X3 can be estimated by means of a calculation model from the values humidity outside X4 in connection with the values interior temperature X1 and outside temperature X2, if a measured value for the input parameter humidity interior X3 is not available.

The parameter limits X12 to X14 are weighted so as to perform polling decision criteria with the input parameters X1 to X11, which are therefore also weighted. One of the decision criteria is the decision block 3 in which it is determined whether there is a threatening situation with respect to the indoor climate. This decision criterion is referred to below as the decision criterion a). In a decision block 4 it is determined whether there is a safety-relevant situation or a safety-relevant interior climate. This decision criterion is referred to below as decision criterion b). In a decision block 6 it is determined whether there is an unpleasant situation for vehicle occupants, so whether there is an unpleasant indoor climate. This decision criterion is referred to below as decision criterion c).

The decision criteria are queried one after the other, the decision criterion b) being queried if the decision criterion a) is not present. The decision criterion c) is queried if the decision criterion b) is not present. The named order of the query is preferred. Of course, another order, or a combination query is conceivable or suitable.

Will in the decision block 3 the decision criterion a) positively recognized, so that a threatening situation in the interior of the vehicle is present, directly with the block 7 continued, wherein a signal is generated, which disables the split cooling or the warm-up concept. This may be the case if the actual interior temperature is far below a correspondingly defined parameter limit value for this decision criterion. It is essential that due to the Heizwunsches the driver's occupants the warm-up concept is disabled, although the warm-up phase of the engine is not yet completed. The procedure is with the block 7 initially stopped, but is restarted at appropriate intervals.

Will in the decision block 3 a decision criterion a) is not recognized, with the decision block 4 in which the decision criterion, b) is queried, so that it is recognized whether a safety-relevant situation exists in the interior of the vehicle. If this is the case, it will be with the block 7 continued, so that the warm-up concept is deactivated as before, although the warm-up phase is not yet completed. This could be the case, for example, if the danger of misting and / or freezing disks is detected. The procedure is with the block 7 initially stopped, but is restarted at appropriate intervals.

Will in the decision block 4 but the decision criterion b) is not recognized, with the decision block 6 in which it is queried whether an unpleasant indoor climate is present. If it is detected that there is a pleasant indoor climate, it is marked with a position map block 8th continued, which input parameters such. B. Heater switch position X17, Eco button position X18, position window X10 and / or position roof window X11 are supplied. In a subsequent decision block 9 it is determined whether there is a clear heating request of the vehicle occupants. If that is not the case, it will be with a block 11 continued, in which a signal causes activation of the warm-up concept or continue to allow its implementation. If this is the case, then with the block 7 continued so that the warm-up concept is deactivated as before.

Will in the block 6 recognized that an unpleasant indoor climate is present, a temperature map block 13 the input parameters X1, X2 and X16 supplied with the associated parameter limit values. In a subsequent decision block 14 it is determined whether the present coolant temperature is sufficient for heating or not. If it is detected that the coolant temperature X16 is sufficient, the block is used 11 and a block 12 continued, in which a signal is generated, which controls the heating power by means of the coolant flow or controls. If it is detected that the actual coolant temperature X16 is not sufficient for heating, it will start with another temperature map block 16 which the input parameters X1 and X2 are supplied with associated parameter limits, so that in a subsequent decision block 17 It is determined whether the actual outside temperature X2 is high enough to control the heating power via the outside air temperature and fans. If this is the case, a corresponding signal is displayed in a block 18 generated simultaneously with the block 11 is continued, so that the warm-up concept is activated or remains active. In contrast, in the block 17 found that the outside temperature X2 is not high enough, becomes the block 8th jumped, taking the procedure with the blocks 9 . 12 and 7 is continued.

The parameter limits are preferably for each of the decision criteria a) to c) but also for the further decisions 14 and 17 with different amounts, whereby suitable parameter limits can be determined according to the decision to be made.

Claims (5)

Method for optimizing a thermal management in a motor vehicle with an internal combustion engine, comprising a warm-up concept according to the principle of the split cooling concept, in which a cooling medium flow is interrupted during the warm-up phase of the internal combustion engine by a cylinder block, wherein the motor vehicle has heating elements full the recording of at least one input parameter (X1 ... X18), determining a deviation of the actual amounts of the input parameters (X1 ... X18) from parameter limit values (X12, X13, X14) related to decision criteria (a), b), c)), and Intervention in the warm-up concept according to the determined deviation if there is a heating request from vehicle occupants. A method according to claim 1, characterized in that the decision criteria are queried successively, wherein the decision criterion b) is queried if the decision criterion a) is negated, and wherein the decision criterion c) is queried if the decision criterion b) is answered in the negative. A method according to claim 1 or 2, characterized in that as input parameters switch positions and positions of functional elements, such. As a heated windscreen (X5), a heated rear window (X6), front and / or rear windshield wiper (X8, X9), side windows (X10) and / or a possible roof window (X11), and an interior temperature (X1), a Outside temperature (X2), a humidity value in the interior (X3), an external humidity value (X4), the coolant temperature (X16), a component temperature, a blower position, a position of the air flow, a heating position, an air conditioning setting and / or a recirculation flap position are recorded. Method according to one of the preceding claims, comprising a first map block ( 2 ), to which the input parameters (X1... X11) are fed, successively polling decision criteria (a), b), c)) in decision blocks ( 3 . 4 . 6 ) wherein the warm-up concept is deactivated at least in accordance with the preferably percentage deviation if the decision criteria (a), b)) are determined by means of the decision blocks ( 3 . 4 ) are determined to be fulfilled, wherein the warm-up concept is deactivated at least in accordance with the preferably percentage deviation if the decision criterion (c)) is determined by means of the decision block ( 6 ) is determined as not satisfied, and if in a decision block ( 9 ), that the warm-up concept is deactivated, at least in accordance with the preferred percentage deviation, even if the decision criterion (c)) is determined by means of the decision block (FIG. 6 ) is satisfied in a decision block ( 14 ) but it is determined that a coolant temperature (X16) has an insufficient high heating temperature, and then in a decision block ( 17 ) it is determined that an outside air temperature (X2) has a heating temperature that is not sufficiently high, and then with the decision block (X2) 9 ) is continued. Use of a method for optimizing thermal management in a motor vehicle having an internal combustion engine, comprising a warm-up concept, wherein the motor vehicle has heating elements according to one of the preceding claims, wherein the warm-up concept is intervened in accordance with recognized decision criterion (a), b) or c)).

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