DE102020115896A1 - Method and assistance system for thermal management in a motor vehicle and motor vehicle - Google Patents

Abstract

The invention relates to a method and an assistance system for thermal management in a motor vehicle and a corresponding motor vehicle. In the method, based on an operating strategy of the motor vehicle, a prognosis for an energy expenditure and a resulting future temperature behavior is created. Based on the prognosis, the operating strategy is evaluated with regard to at least one predetermined criterion. Depending on the evaluation, the operating strategy is then modified in order to achieve an evaluation that is improved with regard to the criterion. The motor vehicle is then controlled in accordance with the operating strategy modified in this way.

Description

The present invention relates to a method and an assistance system for thermal management in a motor vehicle and a corresponding motor vehicle.

In the field of vehicle technology and development, there are often conflicting goals when designing components. For example, a design at the operating range limit can enable a maximum output to be called up at any point in time as well as continuous operation with maximum output and thus offer a high degree of convenience and flexibility. However, such a design is typically complex and expensive and can lead to increased weight and energy consumption. Therefore, a different design premise is often used, for example to enable more energy-saving operation. For this, however, not only the pure hardware design is important, but also a correspondingly adapted control during operation in order to implement or comply with the design premise and still cover the respective requirements during operation as best as possible, such as a need for drive energy or a need for Cooling and / or heating power for the thermal conditioning of vehicle components.

Current motor vehicles are often operated in a standby state during operation, which enables instantaneous retrieval of a maximum possible power and in which, for example, temperature control tasks are carried out reactively on the basis of predetermined temperature threshold values. This can ultimately result in unnecessary energy consumption for the respective actual operation and power requirements.

Especially for vehicles with a traction battery, the thermal conditioning, i.e. the temperature control of such a battery, can represent an essential factor for the energy requirement as well as for the performance of the vehicle. Traction batteries commonly used nowadays have the property that they only work optimally in a limited temperature range. With this in mind, the DE 10 2012 204 410 A1 a method for operating a battery arrangement of a motor vehicle. A heat loss from the battery arrangement is calculated on the basis of the expected energy consumption. Furthermore, a temperature profile of the battery arrangement is predicted on the basis of the calculated heat loss and expected ambient conditions and / or usage parameters. The temperature of the battery arrangement is then set on the basis of the predicted temperature profile.

The temperature control or air conditioning of a vehicle interior can also represent an important factor for the energy requirement and possibly conflict with other needs or requirements. With this in mind, the DE 10 2014 226 514 A1 describes a method for air conditioning an electric or hybrid vehicle. Both an interior and a high-voltage battery of the respective vehicle can be air-conditioned by means of the vehicle's air conditioning system. In the process, for preconditioning the university storage system, it is subcooled in a preconditioning mode by means of the air conditioning system to a temperature below a high-voltage storage system operating temperature. The high-voltage storage unit can therefore be cooled by means of the air conditioning system, although there is currently no cooling requirement with regard to the high-voltage storage unit. This preconditioning then creates a cold buffer. Here too, however, provision can be made for the relevant component to be cooled by means of the air conditioning system when the operating temperature of the high-voltage storage device or a comfortable temperature is exceeded.

From the point of view of improved energy efficiency, the DE 10 2012 208 613 B4 a method for thermal conditioning of rechargeable vehicle energy storage systems is known. On the basis of a specific route, a battery of a vehicle is conditioned by a correspondingly selected conditioning action. To select a temperature from several target temperatures, an energy efficiency value is calculated for several temperatures and an energy efficiency is estimated. The temperature is then selected to have the greatest energy efficiency value.

The object of the present invention is to enable an improved, in particular particularly energy-saving or efficient, operation of a motor vehicle. According to the invention, this object is achieved by the subjects of the independent claims. Advantageous further developments and refinements of the present invention are specified in the dependent claims, in the description and in the figures.

A method according to the invention is used for heat management or for temperature or energy management in or for a motor vehicle. The method according to the invention can therefore be used for managing or adjusting heat or energy flows and, accordingly, of resulting temperatures in the motor vehicle. In a method step of the method according to the invention, a prognosis for an energy expenditure and a resulting future temperature behavior created. The predefined operating strategy can be or include, for example, a current operating strategy or a currently planned operating strategy following the respective current point in time. The operating strategy in this sense can include or characterize an actual and / or planned control of components or devices of the motor vehicle, an operating mode or an operating mode, an operation of the motor vehicle along a certain route or through a certain terrain and / or the like. Different operating modes or operating modes can be, for example, sailing operation, recuperation operation, operation with the maximum possible or with restricted, that is to say limited, power availability and / or the like. The prognosis can be created automatically, for example, by means of a corresponding predefined model or a corresponding simulation. For this purpose, relevant parameters for the motor vehicle or its components or devices can be specified, for example with regard to the energy expenditure and the temperature behavior. This can relate to or include, for example, a heat capacity, a power consumption, a heat transfer coefficient and / or the like.

In a further method step of the method according to the invention, the operating strategy is evaluated with regard to at least one predetermined criterion based on the prognosis. Here it can therefore be evaluated or determined on the basis of the prognosis, in particular automatically, whether or to what extent the specified or current operating strategy meets or does not meet the at least one specified criterion. In a further method step of the method according to the invention, the operating strategy is modified, in particular automatically, as a function of this evaluation, in order to achieve an improved evaluation with regard to the at least one predetermined criterion, that is to say, for example, an improved fulfillment of the criterion. The motor vehicle is then controlled on the basis of or in accordance with the operating strategy modified in this way.

In other words, in the method according to the invention for a current or planned operation of the motor vehicle, the use or retrieval of energy or power and a corresponding duration of the respective energy use or power retrieval can be determined or predicted. For example, by means of a predefined model, the effects thereof can then be modeled or determined, in particular with regard to the resulting temperature development or a resulting temperature change of one or more components or devices of the motor vehicle. A thermal or energetic result can therefore be determined or estimated using the specified operating strategy, for example a current or planned characteristic map or control course, a specific target variable and / or a control course in a control loop or the like. Such a result can in particular indicate when and where which temperature or temperature change is reached. For this purpose, a corresponding transfer function can be specified, for example as part of the model, which characterizes a heat transfer and / or indicates which temperature change of one or more components or devices a respective heat transfer or heat input or energy or power demand leads to and / or which proportion of a the respective energy or power is converted into heat or a change in temperature.

In order to limit the computational effort required for this and thus to enable regular recalculation, that is to say a regularly updated forecast, evaluation and modification of the operating strategy during operation of the motor vehicle, linear estimates can be used. Likewise, a time horizon for the prognosis can be limited, that is to say the energy expenditure and / or the temperature behavior resulting therefrom can only be created for a predefined period of time that extends far into the future to a limited extent. For example, the prognosis, in particular during operation, that is to say while driving the motor vehicle, can be made for a period of up to 300 s or up to 30 min or up to 45 min in the future. The respective time period can be selected or specified, for example, as a function of a heat capacity of the respective component or device. This is based on the knowledge that forecasts reaching further into the future can be significantly more uncertain or unreliable and that such a period is long enough to also take into account relatively sluggish thermal reactions, such as temperature changes of components with a relatively high heat capacity.

In the present invention, energy flows or a respective resulting temperature change in the future can therefore be balanced in order to achieve general or generalized planning for the thermal management and ultimately the operation of the motor vehicle. This is made possible in particular by the fact that energy and temperature are universal quantities that are relevant for different types of components and devices, that is, they can be used or evaluated. Through the strategic evaluation of what, for example, a planned operating, control, cooling or heating process, with regard to a duration and / or an intensity of a temperature development would cause, for example, dependencies or influences between different components or facilities can be taken into account and thus ultimately a more efficient heat management strategy or operating strategy can be determined, since a respective future energy or heat demand or expenditure can now be taken into account in a predictive and complementary way. For the evaluation or as a criterion, for example, a cost-benefit ratio, an energy requirement, an efficiency, a comfort, an urgency, a component load and / or the like can be specified or used. This can depend, for example, on a type of motor vehicle, its intended use and / or a target prioritization in the respective individual case.

Outside the operating times of the motor vehicle, for example if it is parked and not used, the limitation of the time or forecast horizon can be extended or removed. This can take place, for example, while the motor vehicle is being charged at a charging station, if an anticipated charging time as well as a current state of charge and an anticipated development or change in the state of charge and / or a charging power - which may be associated with a corresponding heat input or a corresponding change in temperature - are known. In such scenarios, for example, the forecast can be made for a period of time ranging from 1 hour to 8 hours or longer into the future. This then offers advantageous energy-saving and efficiency potential for the next start-up of the motor vehicle.

The, in particular automatic, variation or modification of the operating strategy can be understood as an optimization, for example in order to find an operating strategy that fulfills the at least one specified criterion better or as well as possible, whereby depending on the formulation of the criterion, for example, a higher over- or under-fulfillment of the Criterion can be aimed for. For example, the operating strategy can be modified in such a way that ultimately unnecessary use of energy or energy consumption can be avoided or reduced, in particular depending on or according to the respective actual needs or requirements. This can be done, if necessary, in compliance with specified conditions or boundary conditions, such as a specified minimum or maximum temperature for various components or devices, for example a high-voltage system or a traction battery, an interior, an engine, electronics and / or the like, for a minimum level of comfort , etc., take place. Expressed mathematically, a corresponding optimization, minimization or maximization problem can be solved as part of the method according to the invention.

For example, one or more parameters of the operating strategy can then be modified, in particular optimized, and ultimately the motor vehicle or one or more components or devices of the motor vehicle taken into account in the operating strategy or in the forecast can be configured according to these parameters, i.e. according to the appropriately modified or optimized operating strategy. For example, a power output or demand, an operating time, an operating frequency, an operating time, a gradation of operating times of one or more components or devices, an operating temperature and / or the like can be modified.

The method according to the invention can for example be carried out or continued continuously or regularly during the operation of the motor vehicle, for example at regular predetermined time intervals and / or triggered by predetermined events or situations. The operating strategy can therefore be adapted for this trip or a remaining part of this trip while the motor vehicle is driving. Likewise, the method, at least the creation of the prognosis, the evaluation of the operating strategy and its modification, as already indicated, can be carried out outside of an operating time, that is to say, for example, when the motor vehicle is stationary or when it is parked. During such times, the operating strategy can then, for example, be modified or optimized for a respective expected next use or operation. This can take place automatically, for example, when new data or information is available, for example when the respective operating conditions change. This can be the case, for example, with an automatic detection of a changed weather situation or weather forecast, changed traffic conditions, a change in the scheduling of a user of the motor vehicle and / or the like.

For a particularly precise prognosis of the energy expenditure or the resulting future temperature behavior, efficiency and / or losses of one or more components or devices of the motor vehicle can particularly advantageously be taken into account, for example as parameters in a corresponding model or a corresponding simulation. These can be thermal, mechanical or electrical efficiencies or losses, for example. As a result, it can be determined or estimated particularly precisely how the temperature will change during a specific operation of the respective component or Facility will change, i.e. which heat flows are likely to result.

The prognosis and the operating strategy can ultimately relate to any components or devices of the motor vehicle, in particular components of a drive train, electrical consumers connected to an electrical system of the motor vehicle and / or components connected to a cooling system or a cooling circuit or components that are to be cooled or temperature-controlled or facilities.

Using the example of a high-voltage battery, in particular a traction battery, it can be taken into account by the method according to the invention that this battery may have less performance outside an optimal temperature range, but a correspondingly reduced performance for a certain journey or a certain use - for example in an urban environment Operation outside the optimal temperature range can be sufficient, since there, at least typically or based on experience, no maximum power output, for example to reach a maximum speed of the motor vehicle, is requested or called up. On the basis of this knowledge, an additional energy requirement due to a loss in efficiency of the traction battery due to a non-optimal temperature can then be sawed off against the energy requirement for bringing the traction battery temperature to the optimal operating temperature. In particular, an expected operating time, for example until a current navigation destination is reached, can be taken into account.

While conventional static heat management or operating strategies, for example, would provide for energy-intensive heating of the traction battery solely because the temperature at the beginning of the journey is outside the optimal temperature range, the method according to the invention can be used over a certain period of time, possibly even over the entire current use or the entire current journey, if necessary, energy can be saved by eliminating the need to heat the traction battery if the energy required for this, for example due to a relatively short journey time, is not more than offset by a resulting gain in efficiency in the last section of the journey can.

In another example, a heat input into the traction battery or, for example, into the interior of the motor vehicle resulting from the operation of one or more other components or assemblies of the motor vehicle can be determined and, for example, result in a dedicated heating device for the traction battery or the interior not or is only operated with reduced power, which can ultimately also lead to energy savings without significant loss of quality or comfort. Ultimately, a budget planning or a methodology for estimating and taking into account an actual requirement or consumption can be applied via a model and evaluation-based feedback in order to enable an improved, in particular particularly energy-saving or efficient, operation of the motor vehicle.

In an advantageous embodiment of the present invention, the creation of the prognosis, its evaluation and the corresponding modification of the operating strategy are carried out iteratively and the motor vehicle is controlled according to the operating strategy that is best found with regard to the criterion. The optimization of the operating strategy can vary iteratively, for example depending on the evaluation, output variables, assumptions, control instructions and / or other parameters of the operating strategy, create a new forecast for this, make a new strategic assessment for the corresponding new forecast, and these steps or processes repeated several times. This can be carried out or repeated automatically, for example, for a predetermined period of time, for a predetermined number of iterations or runs and / or until a predetermined goal is reached. A corresponding predefined goal can be, for example, a predefined acceptable use of energy per route and / or per time interval or a specific relative improvement compared to the respective original operating strategy. As a result, the amount of calculation and time required can be limited in order to ensure a certain performance or consistency of the method or of its application. It can also be taken into account that after a certain improvement has been achieved, further iterations would probably lead to ever smaller improvements. The iteration can then be terminated as soon as the improvements achieved from iteration to iteration fall below a predetermined threshold value.

In a further advantageous embodiment of the present invention, the prognosis is carried out differentially starting from a given starting point in order - in particular only - to predict a relative temperature change. In other words, only temperature changes are then determined with regard to the temperature, but no absolute values of the temperature and / or the energy requirement are determined, for example. The given starting point can be given, for example, by a current operating state of the motor vehicle. For this purpose, for example, current sensor data or, for example, data available via a data bus of the motor vehicle can be called up and used accordingly. The differential approach proposed here can, if necessary, save effort and / or improve reliability. Likewise, for example, individual temperature sensors are not necessarily required on every component or device to determine the respective current starting temperature.

In a further advantageous embodiment of the present invention, the prognosis is made for discrete time steps or in discrete time steps. Time intervals in the range from 15 s to 60 s, preferably 30 s, can, for example, lie between such time steps. In other words, a new forecast is then made only or only after this time interval has elapsed, that is to say when the next time step is reached. This saves computational effort compared to a continuous forecast. At the same time, however, there is no significant deterioration in the eventual operation of the motor vehicle, since thermal systems anyway have a certain inertia and, for example, temperatures do not change abruptly.

In a further advantageous embodiment of the present invention, the operating strategy includes an operation of several different devices of the motor vehicle. The prognosis is then made for a combined operation of these multiple devices, taking into account a thermal influence between these devices. In particular, devices with different primary operating or active energy types and / or different influenced media can be taken into account. For example - depending on the equipment of the respective motor vehicle - an internal combustion engine, an electric machine or battery, a cooling unit, a gearbox, a bearing or a shaft, a braking device, a damper device and / or the like can be considered as different devices. Different energy or operating modes can be of primary importance for such different devices, so the different devices can act in different physical or energetic domains, for example mechanics, electrics, fluidics, etc. However, a primarily electrically operated device, for example, can also generate heat that are transmitted to a primarily mechanically acting device, for example, and can influence this or vice versa.

By considering or taking into account such different devices as well as their combined operation, dependencies or influences can advantageously be taken into account, which ultimately enable more efficient or more energy-saving operation of the motor vehicle overall. For example, an isolated consideration of a device could lead to a certain energy demand and temperature prognosis, which can be relatively imprecise in actual operation of the motor vehicle with several operated devices, since energy or heat generated or dissipated by other devices and their influence is not taken into account. With the present invention, the prognosis can therefore be made particularly precisely and reliably and thus the energy-saving potential that can result from the combination of several devices can be exploited. Combined operation of several devices can mean or include alternating operation, that is to say operation of several devices one after the other, as well as at least temporarily simultaneous operation of several devices.

In a further advantageous embodiment of the present invention, the operating strategy is modified as a function of thermal inertia of at least one device of the motor vehicle taken into account in the operating strategy or in the prognosis. In particular, premature shutdown and / or temporarily interrupted operation of the device can be provided, that is to say, for example, can be planned in the operating strategy. A sluggish or delayed reaction of the temperature of the respective device to a change in an energy supply or energy withdrawal or an operating state is taken into account here. In this way, for example, the operating temperature can be reached or maintained in an optimal or sufficiently good range for the respective device or a further device thermally coupled to it, whereby operating time or operating power and thus energy expenditure can be saved at the same time.

For example, a heating device can be switched off before a current navigation or travel destination is reached, in particular if there is likely to be an interruption in the operation of the motor vehicle there. During the operation remaining after the heating device has been switched off until the navigation or travel destination is reached, the temperature of the device can then decrease, but still remain within acceptable ranges or limits due to the thermal inertia and thus ultimately enable more energy-efficient operation of the motor vehicle. Likewise, for example, an air conditioning device can be used to control the temperature of a device or, for example, the interior space is temporarily interrupted, that is to say operated at intervals. This can take into account that even in such an interval-like or temporarily interrupted operation, the temperature will not change abruptly, but will react slowly. Thus, at least over a certain period of time or a certain operating period, temperature control can be achieved within acceptable ranges or limits with reduced energy consumption. The respective thermal inertia of the device or devices can, for example, be specified as a parameter for the model mentioned. Likewise, for example, a thermal mass, a material composition, any thermal insulation that may be present and / or the like can be specified as corresponding parameters for the device or devices of the motor vehicle.

In a further advantageous embodiment of the present invention, probable conditions of use of the motor vehicle are determined for a respective forecast period and these conditions of use are taken into account for the forecast. The forecast period in this sense is the period for which the forecast is made, that is to say the energy expenditure and / or the resulting temperature behavior is forecast. The conditions of use can be or include, for example, ambient conditions at a place of use or operation of the motor vehicle, an anticipated load on the motor vehicle, for example due to external temperatures or a barometric altitude or an incline to be mastered along a respective route and / or the like. Such conditions of use can have a significant influence on an energy requirement and a resulting thermal behavior of the motor vehicle, this influence also being different for different devices and components of the motor vehicle or being different in strength. By taking these operating conditions into account, a more precise and more reliable forecast can ultimately be made and thus, if necessary, higher energy efficiency or lower energy consumption can be achieved.

In a further advantageous embodiment of the present invention, operating patterns of the motor vehicle are recorded and learned using a machine learning device. An operating pattern predicted by this device for a respective forecast period is then taken into account or used as a basis for the forecast. A machine learning device in this sense can include, for example, a self-learning algorithm or an artificial neural network or the like. For example, regular trips between certain locations at certain times, use of the motor vehicle depending on the weather, a certain speed or performance requirement profile, for example on a certain route section or a certain type of road, and / or the like can be recorded as operating patterns. With the respective predicted operating pattern, routes typically or regularly traveled by a respective user of the motor vehicle, a driving profile, a driver type, a typical traffic density and / or other user habits and / or the like can be taken into account, in particular with regard to the respective energy requirement or the Parameters influencing heat or temperature development. By learning such an operating pattern and taking it into account for the prognosis, it can be created in a vehicle-specific or user-specific manner and thus turn out to be particularly accurate and reliable in each case.

In this way, too, an improved energy efficiency or a reduced energy consumption of the motor vehicle can ultimately be achieved. For example, heating up the traction battery as quickly as possible to a temperature optimized for maximum power output can be dispensed with if, according to the learned operating pattern, a relatively short drive with a relatively low power requirement by a more defensive driver is expected. Likewise, for example, an air conditioning output for temperature control of the interior of the motor vehicle can be reduced if the windows or an openable top or roof of the motor vehicle are always opened or turned off under the given ambient conditions according to the learned operating pattern, since then the influence of the air conditioning device on the conditions in Interior space can be correspondingly reduced or even negligibly small anyway.

Another aspect of the present invention is an assistance system for a motor vehicle. The assistance system according to the invention has a data processing device with an input interface for acquiring or receiving operating data and with an output interface for outputting a control signal. The operating data describe an operation of the motor vehicle, for example its operating state, a previous, current and / or future operating strategy or the like, in particular individual devices or components of the motor vehicle. The assistance system, in particular the data processing device, is set up to execute at least one variant or embodiment of the method according to the invention, in particular automatically or partially automatically. For this purpose, the data processing device can, for example, be a computer-readable one Have data memory and a processor device connected thereto. A program code or a computer program can then be stored on the data memory, which codes or represents the method steps or sequences of the method according to the invention or corresponding control instructions and can be executed by the processor device in order to cause the assistance system to carry out the method automatically.

Another aspect of the present invention is a motor vehicle which has at least one component or device that converts energy during operation and an assistance system according to the invention for automatically controlling or regulating the at least one component or device. The motor vehicle according to the invention can therefore in particular be the motor vehicle mentioned in connection with the method according to the invention and / or in connection with the assistance system according to the invention.

Further features of the invention can emerge from the claims, the figures and the description of the figures. The features and feature combinations mentioned above in the description as well as the features and feature combinations shown below in the description of the figures and / or in the figures alone can be used not only in the respectively specified combination, but also in other combinations or alone, without the scope of the invention to leave.

• 1 eine schematische Übersichtsdarstellung zur Erläuterung eines Wärmemanagements in einem Kraftfahrzeug;
• 2 eine schematische Darstellung zur Veranschaulichung eines Verfahrens für das Wärmemanagement;
• 3 eine erste schematische Darstellung zur weiteren Veranschaulichung des Wärmemanagements; und
• 4 eine zweite schematische Darstellung zur weiteren Veranschaulichung des Wärmemanagements.

The drawing shows in:

• 1 a schematic overview illustration to explain thermal management in a motor vehicle;
• 2 a schematic representation to illustrate a method for thermal management;
• 3 a first schematic representation to further illustrate the thermal management; and
• 4th a second schematic representation to further illustrate the thermal management.

Identical and functionally identical elements are provided with the same reference symbols in the figures.

In technical applications, there can be conflicting goals between different interpretations or criteria or desired goals, which can ultimately lead to unnecessary energy consumption. Variably distributing or avoiding such unnecessary energy consumption can, however, be used specifically to increase systematic deviations, for example between hardware design limits and operating limits, at least essentially without any loss of quality or use, and to save energy and / or monetary costs. For example, drive or vehicle components that are widely used nowadays are actively cooled or heated when they are in certain predetermined temperature ranges. Whether the energy expenditure required for this is worthwhile and takes account of a future goal is often disregarded, i.e. not taken into account for a respective vehicle operating strategy. A predicted duration of an energy expenditure and its result or effect is therefore often not evaluated in such a way that it is derived from it whether the respective energy expenditure should or should not be carried out at all. However, this problem gives rise to significant, previously unused efficiency and energy savings potential, especially in the field of electric vehicles. These can be exhausted if not only the currently prevailing actual situation is taken into account. Rather, data or information that are available in the vehicle, such as navigation data with regard to a probable destination arrival or a route structure or the like, can be specifically taken into account in order to ultimately reduce energy consumption to reach the respective destination.

1 shows a schematic overview representation with a road 10 on which is a motor vehicle 12th from a currently displayed starting position to a navigation destination 14th emotional. The car 12th thereby becomes a driver 16 controlled, but could also be in an autonomous or semi-autonomous driving mode. In the present case, the motor vehicle 12th a detection device 18th on. By means of this detection device 18th can, for example, environmental data and / or operating data of the motor vehicle 12th are recorded. The detection device 18th is shown here schematically as a unit, but can also include several sub-devices. The motor vehicle also has 12th several energy-converting devices, one of which is an air-conditioning device here as an example 20th , an assistance system 22nd , a battery 24 and a drive device 26th are shown. These facilities are here via an on-board network 28 of the motor vehicle connected to each other. Likewise, at least some of these devices can by their spatial arrangement relative to one another and / or via other parts or components or structures of the motor vehicle 12th be thermally coupled to one another, i.e. influence one another thermally in their operation.

For an application example it is assumed that the motor vehicle 12th at the starting position shown in a cooled-down state by the driver 16 is put into operation. At this point in time there are several strategic operational goals that require a relatively large amount of energy to be achieved. On the one hand, an interior or passenger compartment should be warmed up and, on the other hand, the battery 24 or the drive device 26th heated to an optimal operating temperature. These goals or their priority or importance can change, for example depending on the customer's request, a respective planned route, in particular its length and / or gradient, current environmental conditions, a current vehicle status, for example a state of charge (SoC) of the battery 24 and / or the like more. In the present example, let the planned route to the navigation destination be 14th relatively short, so that it can be mastered in a few minutes, for example. The battery can then be nonsensical in terms of operational strategy or energy 24 or the drive device 26th and to heat up the passenger compartment at full power as the motor vehicle 12th after a few minutes when reaching the navigation destination 14th is parked in the relatively cold environment anyway. If these additional boundary conditions are taken into account, there would possibly be self-heating due to the operation of the equipment of the motor vehicle 12th sufficient to display the current destination, i.e. the navigation destination 14th to achieve with a minimum of comfort. The heating energy for temperature control of the passenger compartment and / or the battery 24 and / or the drive device 26th At least some savings could have been made, which would ultimately have resulted in lower energy consumption - possibly despite the lower performance or operating efficiency of the battery 24 on the way to the navigation destination 14th .

The respective driving project, that is to say a respective operation of the motor vehicle, can be used for a correspondingly promising and beneficial assessment 12th , energetically discretized and as many factors influencing efficiency or energy demand as possible can be taken into account in a thermal energy plan, i.e. a prognosis of the energy demand or energy expenditure and a resulting temperature behavior.

For further illustration shows 2 an overview scheme. First of all, in a comparison 30th it can be determined whether an actual temperature T (to) of the motor vehicle 12th or the components or devices of the motor vehicle 12th at a current point in time or starting point in time to is greater or less than at least a predetermined temperature threshold value. Depending on a respective comparison result and a current performance or performance requirement P (to), a control can then 32 for example a conditioning actuator 36 , so a temperature control device, take place. This would then lead to a supply or removal of a corresponding amount of heat Q (to) to or from a temperature control object 34 , that is to say a component or device of the motor vehicle to be temperature-controlled 12th , to lead. Thereupon arises for this tempering object 34 a new changed actual temperature T (t ₀ ) + ΔT a. However, such a relatively simple actual size threshold comparison and a corresponding control or temperature control does not necessarily lead to an optimal result in terms of energy efficiency or a minimized energy requirement.

Therefore, the currently planned activation 32 , one at the current time t ₀ intended operating strategy, initially processed further. A discrete energy balance is drawn up, with the at different times t ₀ , t ₁ , ..., t _n performance requirements P (to), ..., P (t _n ) that are likely to exist in accordance with the operating strategy as input variables of the conditioning actuators 36 supplied in a simulation or modeling and resulting heat quantities or heat flows Q (t ₀ ), ..., Q (t _n ) are determined. These are then a given model 38 of the tempering object 34 or the components or devices of the motor vehicle 12th , fed. Using this model 38 will then be used at the appropriate times t ₀ , ..., t _n resulting temperature changes dT (t ₀ ), ..., dT (t _n ) are determined.

On the basis of these variables or an output of the model 38 a strategic assessment is then carried out 40 , for example in terms of cost-benefit, urgency, efficiency and / or convenience. This can be done automatically, for example, by a predefined evaluation program or an artificial intelligence. Depending on a result of the evaluation 40 or if this does not, for example, meet a predetermined criterion, then a modification 42 of the operating strategy is carried out. With the operating strategy modified in this way, the 32 take place or be strategically evaluated again in a further iterative run in the manner described in order to ultimately find or determine an improved operating strategy.

3 shows a further schematic overview representation. Here are schematically before a current point in time t ₀ collected historical data 44 as well as for one at the current time t ₀ subsequent future forecast data 46 applied. In a lower part of the illustration are energies or energy components that differ from a thermal energy component E. as well as thermal energy shares Q for a component or device of the motor vehicle 12th , for example for the temperature control object 34 , indicated in bar form. E _v can describe different energies, types of energy or energy components, for example a mechanical or electrical component or energy loss component. Based on the current time t ₀ are for various future discrete points in time t ₁ until t ₆ respective changes in energy flow 48 and heat flow changes 50 forecast and from this a respective temperature forecast 52 that indicates an expected temperature or temperature change of the respective component or device. For the sake of clarity, here are just a few of the energy flow changes 48 and the changes in heat flow 50 marked. The temperature forecasts created in this way 52 about the times t ₁ until t ₆ , i.e. a respective forecast period, are then used as the basis for the evaluation 40 used.

4th shows a further overview, which is constructed according to the same scheme as the illustration in 3 . For the sake of simplicity and clarity, however, there are only forecast data here without restricting the generality 46 for a future time t ₁ shown. In contrast to the representation in 3 are for display in 4th several different types of energy or several different components or devices of the motor vehicle 12th that are to be operated at the same time, for example. This is indicated here by the different indices v, q and x, y. For each of these types of energy or components and the associated heat, there are corresponding individual energy flow changes 48 or changes in heat flow 50 forecast. These predictions or forecasts then become a temperature forecast 52 combined.

Overall, the examples described show how predictive thermal management of a vehicle, in particular of electric drive components, by means of discretely differential energy-balancing temperature forecasts 52 can be realized.

List of reference symbols

10

Street

12th

Motor vehicle

14th

Navigation destination

16

driver

18th

Detection device

20th

Air conditioning device

22nd

Assistance system

24

battery

26th

Drive device

28

Electrical system

30th

comparison

32

Control

34

Tempering object

36

Conditioning actuators

38

model

40

evaluation

42

modification

44

historical data

46

forecast data

48

Energy flow changes

50

Changes in heat flow

52

Temperature forecasts

P.

power

Q

warmth

t0 ... tn

Points in time

T

temperature

E.

energy

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was 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.

Patent literature cited

• DE 102012204410 A1 [0004]
• DE 102014226514 A1 [0005]
• DE 102012208613 B4 [0006]

Claims (10)

Method for thermal management in a motor vehicle (12), in which - based on a predetermined operating strategy of the motor vehicle (12), a prognosis for an energy expenditure (48, 50) and a resulting future temperature behavior (52) is created, - Based on the prognosis, the operating strategy is evaluated with regard to at least one predetermined criterion, - the operating strategy is modified as a function of the evaluation (40) in order to achieve an evaluation (40) which is improved with regard to the criterion, and - The motor vehicle (12) is controlled according to the operating strategy modified in this way. Procedure according to Claim 1 , characterized in that the creation of the prognosis, its evaluation (40) and the corresponding modification (42) of the operating strategy are carried out iteratively and the motor vehicle (12) is controlled according to the operating strategy found best with regard to the criterion. Method according to one of the preceding claims, characterized in that the prognosis is carried out differentially starting from a given starting point (to) in order _{to predict a relative temperature change (dT (t n} ), ΔT). Method according to one of the preceding claims, characterized in that the prognosis is made for discrete time steps (t _n ), in particular with a time interval in between in the range of 15s to 60s, preferably 30s. Method according to one of the preceding claims, characterized in that the operating strategy comprises an operation of several different devices (20, 24, 26, 34) of the motor vehicle (12), the forecast for a combined operation of these several devices (20, 24, 26, 34) is created and a thermal influence between these devices (20, 24, 26, 34) is taken into account. Method according to one of the preceding claims, characterized in that the operating strategy is modified as a function of thermal inertia of at least one device (20, 24, 26, 34) of the motor vehicle (12) taken into account in the operating strategy, in particular by premature shutdown and / or a temporarily interrupted operation of the device (20, 24, 26, 34) is provided. Method according to one of the preceding claims, characterized in that expected conditions of use of the motor vehicle (12) are determined for a respective forecast period (t ₁ -t _n ) and these conditions of use are taken into account for the forecast. Method according to one of the preceding claims, characterized in that operating patterns of the motor vehicle (12) are recorded and learned by a machine learning device (22) and an operating pattern predicted by this for a respective forecast period is taken into account for the forecast. Assistance system (22) for a motor vehicle (12), having a data processing device with an input interface for capturing operating data describing operation of the motor vehicle (12) and with an output interface for outputting a control signal, the assistance system (22) being set up for this purpose to carry out a method according to any one of the preceding claims. Motor vehicle (12), having at least one device (20, 24, 26, 34) which converts energy during operation and an assistance system (22) according to one of the preceding claims for automatically controlling the at least one device.

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