DE102019104324A1 - Method for determining an operating point of an internal combustion engine - Google Patents

Abstract

Method (100) for determining an operating point (BP) of an internal combustion engine (10) of a vehicle (2) with an electrical machine (20), the following steps being provided: - Operating (101) the electrical machine (20) for compensation a delayed power output of the internal combustion engine (10), - detection (102) of a parameter which is specific for a performance of the electrical machine (20) for compensation over a period of time, - selection (103) of the operating point (BP) for the internal combustion engine (10) ) depending on the detected parameter, the operating point (BP) correlating with the delayed power output, - providing (104) the selected operating point (BP) in order to adapt the delayed power output to the performance of the electrical machine (20) at least over the period of time .

Description

The present invention relates to a method for determining an operating point of an internal combustion engine of a vehicle with an electrical machine. The invention also relates to a system and a vehicle.

It is known from the prior art that in an internal combustion engine of a vehicle, a selected gear shift stage of the transmission can have negative effects on the maximum available power of the internal combustion engine and the spontaneous response of the drive train in dynamic load cases. It is therefore known in hybrid vehicles that an electrical machine of the vehicle is used to provide mechanical energy from electrical energy - but also vice versa, e.g. to convert mechanical energy into electrical energy in the event of braking. This can improve consumption and dynamics. However, the performance of the electrical components is often limited in time.

In the DE 10 2017 125 497 A1 a generic method is disclosed.

It is therefore an object of the present invention to at least partially remedy the disadvantages described above when operating a vehicle or an internal combustion engine of a vehicle. In particular, the object of the present invention is to enable improved operation of a vehicle or internal combustion engine of a vehicle. In particular, given a given structural design, an improvement in the dynamics and / or an increase in the energy obtained as a generator and / or a reduction in the fuel consumption of a vehicle should be achieved.

The above object is achieved by a method with the features of claim 1, a system with the features of claim 9 and by a vehicle with the features of claim 11. Further features and details of the invention emerge from the respective dependent claims, the description and the drawings. Features and details that are described in connection with the method according to the invention naturally also apply in connection with the system according to the invention and the vehicle according to the invention, and vice versa, so that with regard to the disclosure, reference is or can always be made to the individual aspects of the invention .

The object is achieved in particular by a method, preferably a control method for a manual transmission of a vehicle, for determining an operating point of an internal combustion engine of a vehicle with an electrical machine, preferably an electric motor. In other words, the vehicle has the internal combustion engine (short: VM) and the electric machine (short: EM), which are in particular part of a drive train of the vehicle.

• - Betreiben der elektrischen Maschine für eine Kompensation einer verzögerten Leistungsabgabe des Verbrennungsmotors, bevorzugt vor und/oder während und/oder nachdem die nachfolgenden Schritte durchgeführt werden,
• - Erfassen, vorzugsweise Messen, eines Parameters, welcher für eine Leistungsfähigkeit der elektrischen Maschine zur Kompensation über eine Zeitdauer spezifisch ist, d. h. insbesondere als Kennwert dafür dient, ob die EM die Kompensation über die Zeitdauer bereitstellen kann, und bevorzugt auch, über welche Zeitdauer die Kompensation konkret möglich ist,
• - Auswählen des Betriebspunktes (insbesondere aus mindestens zwei verschiedenen Betriebspunkten) für den Verbrennungsmotor in Abhängigkeit von dem erfassten Parameter, wobei der Betriebspunkt mit der verzögerten Leistungsabgabe korreliert, d. h. insbesondere, dass bei unterschiedlichen Betriebspunkten unterschiedliche Verzögerungen der Leistungsabgabe vorliegen,
• - Bereitstellen des ausgewählten Betriebspunktes, um vorzugsweise die verzögerte Leistungsabgabe an die Leistungsfähigkeit der elektrischen Maschine mindestens über die Zeitdauer anzupassen, d. h. insbesondere, dass der ausgewählte Betriebspunkt als ein solcher Betriebspunkt bereitgestellt wird, bei welchem die verzögerte Leistungsabgabe an die Leistungsfähigkeit der elektrischen Maschine über die Zeitdauer angepasst ist, und hierdurch die Kompensation mindestens über die Zeitdauer gewährleistet sein kann.

It is provided that the following steps can be carried out, preferably one after the other in the specified order or in any order, with individual steps also being able to be carried out repeatedly and / or at least partially in parallel with other steps:

• - Operation of the electrical machine to compensate for a delayed power output of the internal combustion engine, preferably before and / or during and / or after the following steps are carried out,
• - Detecting, preferably measuring, a parameter which is specific for a performance of the electrical machine for compensation over a period of time, ie in particular serves as a characteristic value for whether the EM can provide the compensation over the period of time, and preferably also over what period of time Compensation is concretely possible,
• - Selecting the operating point (in particular from at least two different operating points) for the internal combustion engine as a function of the recorded parameters, the operating point correlating with the delayed power output, ie in particular that there are different delays in the power output at different operating points,
• - Provision of the selected operating point in order to preferably adapt the delayed power output to the performance of the electrical machine at least over the period of time, ie in particular that the selected operating point is provided as such an operating point at which the delayed power output to the performance of the electrical machine over the Duration is adapted, and thereby the compensation can be guaranteed at least over the period.

This accordingly has the advantage that an operating point can be determined at which, due to the adaptation to the performance, the maximum compensation is used, which can be guaranteed over the period of time. Thus, when selecting the operating point, not only the current performance of the EM is used, but also the performance over the Duration taken into account. It can also be a future period of time, so that the detection and / or the selection can include a prognosis of what performance the EM will provide for this future period of time. This forecast can e.g. B. can be made possible by the acquisition and statistical evaluation (such as averaging) of the parameter over a temporal measurement duration, the temporal measurement duration not necessarily having to coincide with the duration. This enables an improved utilization of the electrical system, i.e. the EM, and thereby also offers advantages in terms of driving performance and CO ₂ emissions.

The period of time does not relate to a brief period to increase performance, such as brief acceleration, but to a period during which the vehicle travels over longer distances. In other words, repeated operation of the electrical machine for compensation or other functions, e.g. for electric braking. The period of time is thus preferably specific for a longer, not short-term operation of the electrical machine for compensation. Since the parameter for the performance of the electrical machine for compensation is specific over this period of time, the detection can receive a time component in this way, and the selection can use this time component.

It is also advantageous if the vehicle is designed as a motor vehicle, in particular trackless land vehicle, for example as a hybrid vehicle that includes an internal combustion engine and an electric machine for traction, preferably with an on-board traction network and / or high-voltage on-board network and / or an electric motor than the EM. In particular, the vehicle can be designed as a passenger vehicle. In embodiments of hybrid vehicles, a driving mode of the hybrid vehicle is preferably conceivable in which the hybrid vehicle is driven purely electrically so that the internal combustion engine can be switched off. Alternatively or additionally, another driving mode is conceivable in which the hybrid vehicle is only driven by the internal combustion engine and the electric motor is switched off. In addition, the electric motor can be switched on if required. It is also possible for the vehicle to have a manual transmission or an automatic transmission or a continuously variable transmission (such as a CVT transmission) as the vehicle transmission - as the transmission in the drive train of the vehicle to convert the engine speed of the combustion engine to the drive speed. The term high voltage can e.g. B. refer to electrical voltages above 40 V, which can be used in the vehicle electrical system. A high-voltage vehicle electrical system is understood to mean, in particular, a 48 volt vehicle electrical system.

According to a further advantage, it can be provided that the parameter is a measured variable recorded over time (in particular over a measurement period), preferably a temperature or an electrical current or an electrical power or a state of charge of an energy store for supplying energy to the EM. This measured variable can be specific for a measured variable such as the temperature on the electrical machine, and z. B. can be detected at the electrical machine and / or outside the electrical machine. It is possible for the measured variable to be measured directly in the EM or in the case of an electrical lead to the EM or in the energy store. The parameter and / or the measured variable can be specific for a load and / or performance of the electrical machine for compensation over the duration of the EM or the electrical system.

It is also optionally conceivable that the parameter can be used as a root mean square value of an electrical current, i.e. as a so-called RMS current or also an effective value of the current, preferably for the electrical machine and / or for an energy supply to the electrical machine ( 20th ) is recorded. The parameter can also be recorded outside of the EM, e.g. B. in the energy storage and thus in the energy supply, and is thus specific for a load and / or performance of the electrical machine for compensation over the period of time. In this way, the performance of the electrical system can be determined very reliably. It is a variable that is easy to measure and offers a direct link to the system's performance. As an average value, the RMS current is also insensitive to short-term disturbances. Furthermore, this parameter allows the system to self-regulate, since high RMS currents lead to a reduction and low RMS currents to an increase in the current load.

It can be understood as a concept of the invention that, with such a value of the parameter that indicates a high load on the electrical machine (e.g. high RMS current), an operating point is selected that has little electrical support, i.e. H. Compensation required by the electric machine. This is z. B. at higher speeds. If this is now selected, three effects can then be produced that have a self-regulating effect:

Initially, less electrical support, i.e. compensation, is required directly in the advance. The parameter, such as the RMS current, can tend to decrease accordingly. If the vehicle now brakes, the braking energy can be converted into electrical energy. Braking powers are generally significantly higher and shorter than drive powers. A higher engine speed can be a Higher frictional power of the motor during braking and possibly reduces the electrical braking power peak, whereby the parameter or RMS current increases less strongly (at the expense of the electrical energy consumed, which can be stored in an energy store for the electrical machine). In this context, a high parameter or RMS current means that the vehicle has had a high electrical energy consumption in the past and may have discharged the battery. A high speed means that, if necessary, a high recharging power can be provided ("conversion of fuel to electricity").

Correspondingly, in the reverse case, it can also apply that at an operating point with a low speed, higher support (compensation) is required and the parameter or RMS current can tend to increase. At an operating point with a low speed, i.e. low drag power, more electrical energy can be used from braking at the expense of an increasing RMS current. In addition, less reloading power can be provided at low speeds. In addition, in the reverse case, when changing from a high speed to a low speed, rotational kinetic energy can be dissipated. This can be recorded directly electrically.

A further advantage can be achieved within the scope of the invention if, in order to record the parameter, measured values are repeatedly measured in the electrical machine and processed together by processing, preferably over a period of at least 3 minutes or at least 10 minutes or at least over the entire period Operating time of the electrical machine. In this case, the processing can preferably include a statistical evaluation, particularly preferably at least averaging, in order in particular to predict the performance as a future performance of the electrical machine. In this way, the performance of the electrical system, ie in particular the EM, can be taken into account when selecting the operating point in order to select the operating point as an operating point which is optimal with regard to consumption, dynamics and loading of the electrical system.

Furthermore, it is optionally possible within the scope of the invention that the electrical machine (EM) is operated in operative connection with the internal combustion engine (VM) in order to provide an additional torque as a compensation torque for the internal combustion engine to compensate for a change in a load requirement for the internal combustion engine. Accordingly, the EM can transfer a force to the VM. For this purpose, the EM is z. B. directly or indirectly operatively connected to the VM, e.g. by means of a gear stage designed as a belt (if the vehicle has a belt starter generator) or acting directly on the crankshaft of the VM (in a crankshaft starter generator). If the VM is to provide energy, e.g. B. for propulsion in the vehicle, the transmission can be used to change the operating point of the VM and improve the efficiency. The disadvantages with regard to the power output which this operating point brings with it, in particular the power difference during the delay in the power output, can be compensated for by the additional torque. E.g. this delay occurs with a target demand on the performance of the VM, i. In other words, during this delay the target requirement is not met by an actual output of the VM. The compensation can then consist in the fact that during this delay the EM provides the compensation torque in order to achieve the target requirement by combining the actual power output of the VM with the power output of the EM.

• - Bestimmen wenigstens zwei verschiedener (oder sämtlicher vorgesehener) Betriebspunkte für den Verbrennungsmotor, wobei bei einem ersten der Betriebspunkte eine geringere Kompensation durch die elektrische Maschine vorgesehen ist, als bei einem zweiten der Betriebspunkte, weil z. B. die Leistungsabgabe bei dem ersten der Betriebspunkte weniger Verzögerung aufweist, als bei dem zweiten der Betriebspunkte,
• - Vergleichen des erfassten Parameters mit einem Schwellenwert, welcher für die Zeitdauer spezifisch ist, z. B. kennzeichnend ist für die Zeitdauer, für die die Kompensation bereitgestellt werden kann, wenn der Parameter dem Schwellenwert entspricht,
• - Auswählen des ersten Betriebspunkts, wenn der Parameter oberhalb des Schwellenwertes liegt, andernfalls Auswählen des zweiten Betriebspunkts, sodass insbesondere bei einem Betrieb des VM in dem ausgewählten Betriebspunkt die verzögerte Leistungsabgabe an die Leistungsfähigkeit der elektrischen Maschine mindestens über die Zeitdauer angepasst ist.

Furthermore, it can be provided within the scope of the invention that the selection of the operating point comprises the following step:

• - Determination of at least two different (or all provided) operating points for the internal combustion engine, with a first of the operating points a lower compensation is provided by the electrical machine than a second of the operating points, because z. B. the power output at the first of the operating points has less delay than at the second of the operating points,
• - Comparing the detected parameter with a threshold value which is specific for the period of time, e.g. B. is indicative of the period of time for which the compensation can be provided if the parameter corresponds to the threshold value,
• - Selecting the first operating point if the parameter is above the threshold value, otherwise selecting the second operating point, so that in particular when the VM is operated at the selected operating point, the delayed power output is adapted to the performance of the electrical machine at least over the period of time.

In this way, the selection can take place as a function of the recorded parameter. In this case, the threshold value can be specific for the duration, ie it can be selected such that the compensation by the electrical machine can be ensured for the duration if the parameter is below the threshold value. For this purpose, the parameter z. B. an RMS stream or a Temperature in the electrical machine and the threshold value corresponding to an RMS current threshold value or a temperature threshold value.

Furthermore, it is conceivable that the selection is carried out as a function of at least one further parameter, the at least one further parameter preferably comprising a driving mode of the vehicle. Such a driving mode is, for example, a mode that can be set by a driver, e.g. B. to adjust the chassis, such as a sport mode or the like. Depending on the driving mode, a higher compensation may be desired so that this can be taken into account in the selection. The driving mode can e.g. B. can also be influenced by an analysis of the driver type. As an alternative or in addition, further variables can be provided as further parameters, e.g. the state of the electrical components (such as the electrical machine or the electrical storage device for supplying energy to the EM), the state of the vehicle (such as pressures, speeds, states of charge, temperatures, or the like ), necessary temporary operating states (such as catalytic converter heating or diagnoses or the like), environmental data (such as navigation, or the like).

• - Anzeigen des ausgewählten Betriebspunktes für einen Fahrer des Fahrzeuges, insbesondere wenn das Fahrzeug ein manuelles Schaltgetriebe aufweist,
• - (Automatisches) Durchführen eines Schaltvorgangs für einen Wechsel in den ausgewählten Betriebspunkt, insbesondere wenn das Fahrzeug ein Automatikgetriebe aufweist.

It can be advantageous if, within the scope of the invention, the provision comprises one of the following steps:

• - Display of the selected operating point for a driver of the vehicle, in particular if the vehicle has a manual transmission,
• - (Automatic) implementation of a shifting process for a change to the selected operating point, especially if the vehicle has an automatic transmission.

This enables the VM to be operated reliably (manually or automatically) in the selected operating mode. Furthermore, the shifting process does not necessarily have to take place by selecting a different shift stage in the same transmission; other adjustment options of the transmission can also be provided. So z. B. a dual clutch transmission can be used in which two gears are engaged in two sub-transmissions at the same time and only a change between the sub-transmissions takes place by actuating the clutches. A multi-stage automatic system with a converter can also be provided, which can set a different operating point by activating the converter (e.g. via a converter lock-up clutch) with the same gear step. In addition, the ability to adjust between switching states can also be implemented by means of dedicated hybrid transmissions, in which the operating point is determined not as a result of switching elements but rather by the operating state of the electrical machines used. Furthermore, it is conceivable that after the selected operating point has been displayed as a shift recommendation (for example in the form of a gear selection indicator), the driver himself carries out the shifting process manually.

• - eine elektrische Maschine, welche für eine Kompensation einer verzögerten Leistungsabgabe eines Verbrennungsmotors bei dem Fahrzeug ausgeführt ist,
• - eine Erfassungskomponente, wie eine elektronische Messanordnung, zum Erfassen eines Parameters, welcher für eine Leistungsfähigkeit der elektrischen Maschine zur Kompensation über eine Zeitdauer spezifisch ist,
• - eine Verarbeitungskomponente, wie ein Mikrocontroller oder eine elektronische Schaltung oder ein Computer, zum Auswählen eines Betriebspunktes für den Verbrennungsmotor in Abhängigkeit von dem erfassten Parameter, wobei der Betriebspunkt mit der verzögerten Leistungsabgabe korreliert,
• - eine Bereitstellungskomponente, wie eine Anzeige oder eine elektronische Schaltung oder ein Steuergerät, zum Bereitstellen des ausgewählten Betriebspunktes, um insbesondere die verzögerte Leistungsabgabe an die Leistungsfähigkeit der elektrischen Maschine mindestens über die Zeitdauer anzupassen.

The invention also relates to a system for a vehicle, comprising:

• - An electrical machine, which is designed to compensate for a delayed power output of an internal combustion engine in the vehicle,
• a detection component, such as an electronic measuring arrangement, for detecting a parameter which is specific for a performance of the electrical machine for compensation over a period of time,
• a processing component, such as a microcontroller or an electronic circuit or a computer, for selecting an operating point for the internal combustion engine as a function of the detected parameter, the operating point correlating with the delayed power output,
• a provision component, such as a display or an electronic circuit or a control device, for providing the selected operating point, in particular to adapt the delayed power output to the performance of the electrical machine at least over the period of time.

The system according to the invention thus has the same advantages as have been described in detail with reference to a method according to the invention. In addition, the system can be suitable for carrying out a method according to the invention.

The invention also relates to a vehicle with an internal combustion engine which has a system according to the invention. The vehicle according to the invention thus has the same advantages as have been described in detail with reference to a system according to the invention.

• 1 eine schematische Darstellung zur Visualisierung eines erfindungsgemäßen Verfahrens,
• 2 eine schematische Darstellung eines Kennfelds einer Verbrennungsmaschine,
• 3 eine schematische Darstellung eines erfindungsgemäßen Systems,
• 4 eine schematische Darstellung eines erfindungsgemäßen Fahrzeuges,
• 5 eine schematische Darstellung eines Leistungssprungs.

Further advantages, features and details of the invention emerge from the following description, in which exemplary embodiments of the invention are described in detail with reference to the drawings. The features mentioned in the claims and in the description can each be essential to the invention individually or in any combination. Show it:

• 1 a schematic representation to visualize a method according to the invention,
• 2 a schematic representation of a map of an internal combustion engine,
• 3 a schematic representation of a system according to the invention,
• 4th a schematic representation of a vehicle according to the invention,
• 5 a schematic representation of a jump in performance.

In the following figures, the same reference numerals are used for the same technical features from different exemplary embodiments.

In 1 is schematically a method according to the invention 100 for determining an operating point BP of an internal combustion engine 10 of a vehicle 2 with an electric machine 20th visualized. Operation takes place according to a first step 101 the electric machine 20th for compensation of a delayed power output of the internal combustion engine 10 . Detection takes place during or afterwards 102 a parameter, which for a performance of the electrical machine 20th is specific to compensation over a period of time. Then there is a selection 103 of the operating point BP for the internal combustion engine 10 as a function of the recorded parameter, the operating point BP correlating with the delayed power output. Provisioning then takes place as a further step 104 of the selected operating point BP to the delayed power output to the performance of the electrical machine 20th to be adjusted at least over the period of time.

2 shows schematically an exemplary map of an internal combustion engine with efficiency isolines. All points on an iso line have the same efficiency. The efficiency can be low at a lower torque DM and rise to a higher torque DM (visualized by the arrow WG). Also shown is a power hyperbola with two possible power-equivalent operating points BP1 and BP2 at different speeds DZ. These two operating points BP1 and BP2 can, for. B. when using a gearbox can be set via different switching stages. E.g. BP1 can be assigned to a first and BP2 to a second switching stage. BP2 is more efficient than BP1. In the case of a dynamic increase in the load, i.e. when an actual power value is to be quickly adapted to a target power value (see e.g. 5 ), however, BP1 has an advantage: Due to the higher speed DZ, significantly greater power reserves can be called up from BP1 than from BP2. Possibly. the efficiency of the new BP1 'can then also be higher than that of the new BP2'. Also is with the internal combustion engine 10 possibly the adjustment dynamics limited by the rate at which the supplied fresh air mass can be increased. In particular with supercharged engines, the adjustment dynamics in BP2 can therefore be worse than in BP1. A transition from BP2 to BP2 'can then take longer than from BP1 to BP1'. This is understood to mean the delayed power output, ie the desired power is accordingly only available with a delay. Therefore, the electric machine can 20th can be used for compensation, ie as an additional drive source. In dynamic situations, this can change the behavior of the internal combustion engine 10 be improved. This is also known as transient compensation. The electric machine 20th fills z. B. the difference between the actual power of the internal combustion engine 10 and the target requirement until the internal combustion engine 10 has reached the target performance.

The use of the electric machine 20th is limited, both by the available electrical energy in the storage 40 as well as the maximum permissible average load on the electrical components, i.e. the electrical machine 20th and electrical storage 40 . In principle, electrical components also show a marked difference between “peak” and continuous performance. For this, z. B. the permissible thermal load capacity of these components is the cause. During operation, the electrical components generate a power loss, which leads to the components heating up. To avoid damaging the components, the heat must be dissipated from the components. Because this derivation can take a longer period of time, the peak performance may be many times greater than the continuous performance over the period of time. With the performance of the electrical machine 20th for compensation over the period of time, it can therefore be this continuous capacity.

Therefore, the parameter which is specific for the time period can be used to provide the compensation with continuous performance. Such a parameter is e.g. B. an RMS current (effective value of the current), which is a typical indicator for a permanent electrical load. Since this is an average value which is insensitive to short-term changes, all too frequent changes to the selected switching stage can advantageously be avoided. In other words, the operating point BP can be selected as a function of the RMS current. If the current value of the Parameter is low, e.g. B. below a threshold value, the second operating point BP2 can be selected. In BP2, the transient torque build-up is worse than in the first operating point BP1. If a higher load (according to BP2 ') is therefore required from BP2, the electrical machine can 20th set a compensation torque until BP2 'is reached. The maximum power that can be represented is then lower based on BP2. The electric machine 20th can be part of the power of the internal combustion engine 10 take over so the load of the internal combustion engine 10 lower and the internal combustion engine 10 to operate again with better efficiency.

If operation (e.g. in the switch position) of BP2 / BP2 'no longer makes sense, a switch to BP1 can be initiated. The combustion engine can do this 10 be accelerated to a higher speed DZ, additional energy is required for this. The electric machine 20th can provide the additional torque and advantageously support a fast shifting process, especially if a high load requirement simultaneously makes it necessary to shift from a second to a first shift stage. This also leaves the electrical current in the electrical machine 20th , i.e. the parameters such as the RMS current or the temperature, increase.

If the current value of the parameter is too high, BP1 can be selected. The internal combustion engine 10 can then, starting from BP1, represent a good transient torque build-up, a high maximum power and a good degree of efficiency at high loads. In the event of a sudden change from BP1 to BP1 ', there is therefore a requirement for electrical support from the electrical machine 20th low. The load on the electrical system also decreases and the parameter decreases. Additional mechanical energy can also be provided by the internal combustion engine 10 are provided by the electrical machine 20th is converted into electrical energy to the storage 40 reload. When the parameter has decreased sufficiently, e.g. B. below the threshold value, the switching stage can be changed, e.g. B. to a second switching stage or BP2. The internal combustion engine can do this 10 be decelerated to a lower speed level, and the electrical machine 20th can possibly use excess kinetic energy to the electrical storage 40 to charge. In this way, the electrical performance of the system can be optimally used, since the selected switching stage also has an effect on the current load (i.e. the RMS current value).

It is also conceivable that such a behavior is also used in the event of electrical deceleration (recuperation). Becomes a vehicle 2 delayed with the drive train described, high braking power may be required. These can in turn be converted into electrical power L. However, this also results in a high component load on the electrical components. Is z. B. braked in a second switching stage, there is a high increase in the RMS current in the electrical machine 20th , but also a high charge of the battery from recuperation. This energy can then be used for the electrical functions in BP2, e.g. B. for compensation. On the other hand, the friction losses of the transmission are at the higher speed level of the first gear stage 30th and internal combustion engine 10 higher than in the second switching stage. This means that some of the necessary braking power can be generated from mechanical friction. This reduces power peaks in the electrical system. This behavior, in which there is a braking phase and a subsequent jump in power, is schematically shown in for BP1 and BP2 5 shown.

In 5 a power L is shown over time t, a distinction being made between a pull Z and a push S. Furthermore, the target power SL is shown, which changes over time. As with the actual performance shown LBP1 ' of BP1 'and the actual performance LBP2 ' can be seen from BP2 ', the advantage of reduced thrust losses can initially be achieved in the case of a thrust S. In other words, a higher recuperation energy, but also a higher RMS current, can be achieved. When switching over the target output SL to "Z", the actual output LBP1 ' offer high dynamics, whereas the actual performance LBP2 ' only provides a low dynamic, as can be seen from the different course of the curves. The disadvantage of BP2 ', namely the delayed build-up (output) of the power, can be caused by the electric machine 20th be compensated.

In 3 is schematically a system according to the invention 1 for a vehicle 2 shown. This has an electrical machine 20th on that for a compensation of a delayed power output of an internal combustion engine 10 at the vehicle 2 is executed. The operative connection of the electrical machine is an example 20th with the internal combustion engine 10 about a translation 50 such as B. Belt 50 , shown, with other solutions for the active connection also come into question. There is also a memory 40 for the electric machine 20th as well as a transmission 30th shown schematically. In addition, there is an acquisition component 201 to capture 102 a parameter provided, this parameter for a performance of the electrical machine 20th is specific to compensation over a period of time. Also is a Processing component 202 Part of a system according to the invention 1 which to choose 103 an operating point BP for the internal combustion engine 10 is used as a function of the recorded parameter, this operating point BP being correlated with the delayed power output. A provisioning component 203 is used to deploy 104 of the selected operating point BP is used in order to enable the delayed power output to the performance of the electrical machine 20th is adjusted at least over the period of time. The provisioning component 203 z. B. be designed as a display device in order to connect the selected operating point BP upstream for a driver. Alternatively, the provisioning component 203 also set the operating point BP automatically, e.g. B. by controlling a manual transmission.

In 4th is schematically a vehicle 2 with an internal combustion engine 10 shown, which an inventive system 1 having.

The above explanation of the embodiments describes the present invention exclusively in the context of examples. Of course, individual features of the embodiments can be freely combined with one another, provided that they are technically sensible, without departing from the scope of the present invention.

List of reference symbols

1

system

2

vehicle

10

Internal combustion engine

20th

Electric machine, electric motor

30th

transmission

40

Electric storage

50

Translation, belt

100

Procedure

101

first procedural step, operation

102

second process step, acquisition

103

third process step, selecting

104

fourth process step, providing

201

Acquisition component

202

Processing component

203

Deployment component

BP

Operating point

DM

Torque

Double room

rotational speed

BP1 BP1 '

first operating point

BP2 BP2 '

second operating point

Flat share

increasing efficiency

L.

power

Z

train

S.

thrust

LBP1 '

Actual output BP1 '

LBP2 '

Actual output BP2 '

SL

Target performance

t

time

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 102017125497 A1 [0003]

Claims (11)

Method (100) for determining an operating point (BP) of an internal combustion engine (10) of a vehicle (2) with an electrical machine (20), the following steps being provided: - Operating (101) the electrical machine (20) to compensate for a delayed power output of the internal combustion engine (10), - Detecting (102) a parameter which is specific for a performance of the electrical machine (20) for compensation over a period of time, - Selecting (103) the operating point (BP) for the internal combustion engine (10) as a function of the detected parameter, the operating point (BP) correlating with the delayed power output, - Providing (104) the selected operating point (BP) in order to adapt the delayed power output to the performance of the electrical machine (20) at least over the period of time. Method (100) according to Claim 1 , characterized in that the parameter is a measured variable recorded over time, preferably a temperature or an electrical current or an electrical power, which is recorded on or outside the electrical machine (20) and / or for a load on the electrical machine (20) is specific. Method (100) according to Claim 1 or 2 characterized in that the parameter is recorded as a root mean square value (RMS) of an electric current, in particular in the case of the electric machine (20) and / or in the case of an energy supply to the electric machine (20). The method (100) according to any one of the preceding claims, characterized in that, in order to detect (102) the parameter, measured values are repeatedly measured in the electrical machine (20) and processed together by processing, preferably over a period of at least 3 minutes or at least 10 minutes or at least over the entire operating time of the electrical machine (20), the processing preferably comprising a statistical evaluation, particularly preferably at least averaging, in order to forecast the performance as a future performance of the electrical machine (20). Method (100) according to one of the preceding claims, characterized in that the electrical machine (20) is operated in operative connection with the internal combustion engine (10) in order to compensate for a change in a load requirement for the internal combustion engine (10) an additional torque as a compensation torque for the internal combustion engine (10). The method (100) according to any one of the preceding claims, characterized in that the selection (103) of the operating point (BP) comprises the following step: - determining at least two different operating points (BP1, BP2) for the internal combustion engine (10), with one first (BP1) of the operating points (BP1, BP2) a lower compensation is provided by the electric machine (20) than with a second (BP2) of the operating points (BP1, BP2), - comparison of the detected parameter with a threshold value, which for the duration is specific, selecting the first operating point (BP1) if the parameter is above the threshold value, otherwise selecting the second operating point (BP2). The method (100) according to one of the preceding claims, characterized in that the selection (103) is carried out as a function of at least one further parameter, the at least one further parameter preferably comprising a driving mode of the vehicle (2). Method (100) according to one of the preceding claims, characterized in that the provision (104) comprises one of the following steps: - Display of the selected operating point (BP) for a driver of the vehicle (2), in particular when the vehicle (2) is on has a manual gearbox, - Carrying out a shift process for a change to the selected operating point (BP), in particular if the vehicle (2) has an automatic transmission. System (1) for a vehicle (2), comprising: - An electrical machine (20) which is designed to compensate for a delayed power output of an internal combustion engine (10) in the vehicle (2), - a detection component (201) for detecting (102) a parameter which is specific for a performance of the electrical machine (20) for compensation over a period of time, - A processing component (202) for selecting (103) an operating point (BP) for the internal combustion engine (10) as a function of the detected parameter, the operating point (BP) correlating with the delayed power output, - A provision component (203) for providing (104) the selected operating point (BP) in order to adapt the delayed power output to the performance of the electrical machine (20) at least over the period of time. System (1) according to Claim 9 , characterized in that the system (1) for execution a method (100) according to one of the Claims 1 to 8th is executed. Vehicle (2) with an internal combustion engine (10), further comprising a system (1) according to Claim 9 or 10 .

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