EP2321137A1

EP2321137A1 - Method for operating a drive of a motor vehicle, and a drive device and an electronic control unit

Info

Publication number: EP2321137A1
Application number: EP09781804A
Authority: EP
Inventors: Jens-Werner Falkenstein
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2008-09-09
Filing date: 2009-08-13
Publication date: 2011-05-18
Also published as: WO2010028926A1; US20110276207A1; CN102149557A; DE102008041897A1

Abstract

The invention relates to a method for operating a drive (2) of a motor vehicle (1), which comprises at least two shafts (4,7) which can each be driven by means of a shaft drive device (3,6), wherein a total drive torque of the motor vehicle (1) substantially corresponds to the sum of the shaft torques applied to the shafts (4,7). According to the invention, a magnitude and/or a change in the magnitude of one of the shaft torques is considered in the control and/or regulation of the remaining shaft torques. The invention further relates to a drive device (20) of a motor vehicle (1), and an electronic control unit.

Description

description

Title method for operating a drive of a motor vehicle and drive device and electronic control unit

The invention relates to a method for operating a drive of a motor vehicle, which has at least two each by means of a shaft drive device driven shafts, wherein a

Total drive torque of the motor vehicle substantially corresponds to the sum of applied to the waves shaft torque. The invention further relates to a drive device and an electronic control unit.

State of the art

Methods of the type mentioned are known from the prior art. They are used, for example, in electric or hybrid vehicles, in which connected to wheels of the motor vehicle shafts are coupled via a ground connected to the wheels. In this type of motor vehicle can be dispensed with a transfer case, such as a central differential or axle differential. Usually, the individual shafts are each assigned a shaft drive device by means of which they can be driven. The total drive torque of the motor vehicle is impressed on the shafts by the shaft drive devices, so that the total drive torque essentially corresponds to the sum of the individual shaft torques. Consequently, a control and / or regulation must be realized, which divides the desired total drive torque of the motor vehicle to the individual shaft moments. For example, DE 10 2004 049 324 A1 discloses a method for controlling and regulating the driving dynamics in motor vehicles with hybrid drive. This method is intended to be used for drives with at least one electric machine and one internal combustion engine. In this case, a total drive torque is distributed to the electric machine and the internal combustion engine such that in sum the desired drive torque desired by the driver is generated. At the same time a yaw moment and thus a self-steering behavior of the motor vehicle to be influenced. Steering interventions are also provided. A degree of distribution is calculated which corresponds to the ratio of the torques of the at least one electric machine to the total drive torque. Thus, the moments of the electric machine and the internal combustion engine are determined and forwarded to them. In certain operating situations of the drive, for example in case of failure of the internal combustion engine and / or the electric machine, it may thus affect the reliability of the motor vehicle, since, for example, a portion of a drive or braking torque is eliminated and changes the total drive torque.

Disclosure of the invention

In contrast, the method for operating a drive of a motor vehicle with the features mentioned in claim 1 has the advantage that said impairment of the operational safety of the motor vehicle is prevented by dangerous changes in the total drive torque can be avoided. This is achieved by taking into account a magnitude and / or a change in the magnitude of one of the shaft moments in a control and / or regulation of the remaining shaft torques. The actual size of one of the shaft moments thus influences the determination of the remaining shaft moments. These can also be appropriately controlled and / or regulated as soon as a change in the magnitude of one of the shaft moments is detected. The drive of the motor vehicle has at least two drivable shafts. For example, therefore, the front and rear axles can be driven separately by means of a respective shaft drive device, front and rear axles can each have an axle differential, or each wheel of the motor vehicle can be connected to its own shaft drive device. The total drive torque of the motor vehicle corresponds essentially to the sum of the individual shaft torques. In this way, dangerous Bethebszustände, which could at least follow a partial failure of one of the shaft drive devices, can be substantially avoided. The failure of the shaft drive device causes a change in the size of one of Shaft moments, so that the size present with it can be taken into account in the control and / or regulation of the remaining shaft torques. It may be provided, for example, that the remaining shaft torques are adjusted so that the change in the size of the one shaft torque is compensated. It is also conceivable that the motor vehicle is stabilized by means of the control and / or regulation, should instability have been caused by the change in the size of the one shaft torque. The method according to the invention can advantageously be used in drives in which the individual shafts each have a shaft drive device and are not connected to one another. However, it can also be used if at least two of the shafts are connected to one another via a coupling, for example via a controllable mechanical coupling, which can be used as a multi-plate clutch in the sense of a central differential. Particularly advantageous method for electric or hybrid vehicles with multiple drive axles is applicable. In the latter case, a unit consisting of an internal combustion engine, a gearbox and possibly an electric machine usually acts on one of the shafts, while one or more further shafts are driven by electric machines in conjunction with a gearbox. Here, shaft is to be understood in the sense of drive axle. The electric machine connected to the internal combustion engine may, for example, be a belt starter generator which is operated to start the internal combustion engine and as a generator. However, the method is also suitable for drives which provide several similar shaft drive devices.

A development of the invention provides that as at least one of the shaft drive devices, an internal combustion engine or an electric machine or a hybrid drive device with at least two different drive units, in particular an electric and an internal combustion engine, or a hydraulic machine is used. The shaft can thus be driven by shaft drive devices of various kinds. At least one of the shaft drive devices may be in the form of the internal combustion engine, the electric machine, the hybrid drive device, or the hydraulic machine. The hybrid drive device has at least two drive units, which are preferably different and formed for example by the electric machine and the internal combustion engine.

A further development of the invention provides that the total drive torque essentially corresponds to a desired drive torque predetermined by a driver of the motor vehicle and / or a driver assistance system. In a normal operation of the drive, therefore, the total drive torque should be matched to a driver's request. This can specify the target drive torque, for example via an accelerator pedal. Also possible is an influence of the driver assistance system on the total drive torque or the target drive torque. The driver assistance system can be formed by various electronic aids, such as a system for maintaining a constant speed, a brake assist, a system for maintaining a certain distance from other vehicles or a stability system. Both the driver of the motor vehicle and the driver assistance system have influence on the target drive torque, which is taken into account as well as the size and / or the change in the size of one of the shaft moments in the control and / or regulation of the remaining shaft torque. In the normal operation of the motor vehicle, the control and / or regulation sets the shaft torques such that the total drive torque, which corresponds to the sum of shaft torques applied to the shafts, is equal to or at least substantially equal to the desired drive torque.

A development of the invention provides that when the total drive torque deviates from the desired drive torque due to a limitation of at least one shaft torque, the deviation of the total drive torque is continuous and / or gradient-limited. If there is a limitation of at least one of the shaft moments, then it may happen that the target drive torque can not be achieved due to the limitation and the total drive torque deviates from this. In this case, the deviation or the change of the total drive torque should be continuous and / or gradientenbegrenzt. The limitation may, for example, due to limits of the shaft drive device (performance limits of internal combustion engine or charge level and / or load and / or Performance limits of an energy storage device or a traction battery), a downshift (for example, boost control to distribute an available energy content of the energy storage or the traction battery on several boosts), a Notlaufzustands a shaft drive device (for example due to a fault in a transmission), a switching operation in the Transmission or a vehicle dynamics system present. The latter can influence individual waves, for example in order to avoid blocking the shaft or the wheel arranged thereon. The limitation can also be caused by a spinning or slipping of the wheels of the motor vehicle on a substrate. In this case, sufficient force can not be transmitted to the ground to achieve the target drive torque. The limitation eliminates at least part of one of the shaft moments, so that it can lead to a sudden increase or decrease in the total drive torque. In order to ensure the safety of the motor vehicle, therefore, the total drive torque should be adjusted or changed continuously and / or gradient-limited. This means that no or at least only slight jumps occur during the deviation of the total drive torque after the occurrence of the limitation. It can also be provided that a speed of deviation of the total drive torque from the desired drive torque is determined via a gradient limitation. This means that, for example, with a rapid change of the target drive torque, the total drive torque should change quickly.

A development of the invention provides that after eliminating the limitation, the total drive torque is adjusted continuously and / or gradientenbegrenzt to the target drive torque. If the limitation is omitted, then the shaft torques can be adjusted again by means of the control and / or regulation such that their sum corresponds to the nominal drive torque. In order to prevent a sudden change in the total drive torque, which could affect the safety of the motor vehicle, the total drive torque is changed continuously and / or gradient-limited. This means that the deviation of the total drive torque from the target drive torque is reduced steadily and / or gradient-limited. The Change takes place until the total drive torque again substantially corresponds to the target drive torque. In this way, the driver of the motor vehicle has sufficient time to adjust to the changed operating conditions and possibly to adjust the target drive torque. Of course, the adaptation of the nominal drive torque in this case can likewise be carried out by means of the driver assistance system.

A development of the invention provides that, for the continuous and / or gradient-limited change of the total drive torque, at least one of the shaft drive devices is operated in an overload range and / or in an unfavorable operating point. During normal operation of the motor vehicle, that is, without limitation, the shaft drive devices should be operated so that neither overloading nor the shaft drive device is operated at an unfavorable operating point. The latter can for example be characterized by a high specific fuel consumption and / or high emission values. If, on the other hand, the limitation exists and the target drive torque can not be achieved due to the limitation of at least one of the shaft torques, in particular without overloading or unfavorable operating points, then at least one of the shaft drive devices can be operated in the overload range and / or the unfavorable operating point to control the steady state and / or gradient-limited change of the total drive torque to allow. For example, in case of failure of one of the shaft drive devices, another shaft drive device is operated at a higher power, in which only a short-term operation without damaging the shaft drive device is possible and at the same time there is a high specific fuel consumption. During such operation of the shaft drive device, the total drive torque is changed continuously and / or gradient-limited, so that the total drive torque is set to a value that allows operation of the shaft drive device in a permanently permissible range. In this way, the safety of the motor vehicle can be significantly increased by the short-term operation of the shaft drive device outside the permanently permissible and / or desired range. Since the operation of the shaft drive device only short-term in the unwanted area, no damage can occur at this.

A development of the invention provides that the continuous and / or gradient-limited change of Gesamtanthebsmoments the

Gesamtanthebsmoment filtered and / or changed according to a ramp. The change of the total drive torque should be jump-free and slow. This can be achieved by using a filter and / or changing the total drive torque according to the course of the ramp, which may be predetermined.

A further development of the invention provides that the change of the total drive torque takes place such that an absolute value of the total drive torque is less than an amount of the desired drive torque and / or the total drive torque approaches zero. During the change of the total drive torque so its absolute value should not exceed that of the target drive torque. The changed total drive torque should therefore always be between the original value of the total drive torque or the nominal drive torque and a zero value. In this way, it can not come to a surprise for the driver increase or decrease of the total drive torque. It can therefore also be provided that the total drive torque runs to zero. This may be provided, for example, in the case of a particularly serious fault in one of the shaft drive devices in order to safely stop the motor vehicle. This means that when the vehicle with positive total drive torque is in a traction mode, the total drive torque is to reduce toward zero as soon as there is a limitation to avoid unwanted acceleration of the vehicle. Conversely, should a negative total drive torque, the motor vehicle is thus in overrun, the total drive torque preferably change toward zero as soon as the limitation occurs to prevent a sudden deceleration.

A development of the invention provides that the target drive torque is filtered. The target drive torque therefore does not correspond directly to the specification of Driver of the motor vehicle, but is merely coupled to this. It is provided that the specification of the driver and / or the driver assistance system is filtered before the total drive torque of the motor vehicle is adapted to it. This is to prevent jumps and / or too rapid changes in the total drive torque of the motor vehicle can occur.

A development of the invention provides that a minimum torque and / or a maximum torque is defined for at least one of the shafts. The shaft drive device connected to the shaft is thus given a torque range in which it is operated. The shaft torque is controlled and / or regulated such that it is greater than the minimum torque or less than the maximum torque or lies between the minimum torque and the maximum torque. The minimum torque and / or the maximum torque can be determined on the basis of the minimum and / or maximum achievable torque of the shaft drive device and / or describe a favorable operating range. Minimum torque and / or maximum torque can thus be chosen so that an operation of the shaft drive device is present in a favorable operating point, for example, with a low specific fuel consumption and / or low pollutant emissions. If there is a limitation, it is possible to deviate from these ideal moments. This means that the minimum torque and / or the maximum torque can be set to other values.

A further development of the invention provides that the minimum torque and / or maximum torque as a function of a torque range which can be provided by the shaft drive device and / or a reduction of one of the shaft drive devices and / or an emergency / fault state and / or a shift in a transmission and / or Values of a vehicle dynamics control is set. The minimum torque and / or maximum torque can thus be matched to the available torque range of the shaft drive device, or to an optimal torque range of the same. An adjustment of the minimum torque and / or the maximum torque can also be made due to a reduction of one of the shaft drive devices. The reduction can For example, be provided due to a malfunction or an unfavorable operating condition (for example, overheating). The shutdown can also be provided in the form of a Boostabregelung to distribute the available energy content of the electrical energy storage or the traction battery on several boost operations. Furthermore, recognized emergency / fault states and switching processes flow into the values of the minimum torque and / or maximum torque. It is also advantageous if the permissible torque range, that is to say the range limited by the minimum torque and / or the maximum torque, is set as a function of the values of a driving dynamics control. This can be provided to increase the stability of the motor vehicle.

A development of the invention provides that the torque range of the shaft drive device is determined as a function of the drive units of the hybrid drive device. If the hybrid drive device is provided as the shaft drive device, the torque range is matched to the drive units of the hybrid drive device. This means that not just one of the drive units, but the whole is considered. For example, the determination of the torque range is carried out to a torque range which is defined by an internal combustion engine and an electric machine.

A development of the invention provides that the operation of the shaft drive device in an overload range and / or in an unfavorable operating point by adjusting the minimum torque and / or maximum torque is allowed. In normal operation, minimum torque and / or maximum torque are set so that the operation in the overload range and / or the unfavorable operating point is not permitted. Should, for example, due to the limitation arise the need to operate at least one of the shaft drive devices in the overload range and / or the unfavorable operating point, the minimum torque and / or the maximum torque is adjusted accordingly, so that the shaft drive device, the operation is allowed in the corresponding area. A development of the invention provides that, in the control and / or regulation of the remaining shaft torques, an inertia of moving elements, in particular of the shafts and / or of the shafts and / or of the drive units, is considered. In an acceleration, for example, a rotational acceleration, in particular of the waves, a proportion of the generated shaft torque is required to accelerate the inertial mass of the rotating shaft. This is equivalent to delaying the wave as well. This means that the total drive torque is reduced by this proportion. A high spin may occur when a vehicle dynamics system or a transmission gear shift affects the minimum or maximum torque of one of the shafts. The proportion by which the total drive torque is reduced, should now not be taken into account in the control and / or regulation of the remaining shaft torque, since it is effectively not the drive of the motor vehicle available. In this case, the focus is on the proportion which is present at the elements to be assigned to the one wave moment.

A development of the invention provides that the inertia is taken into account by using a low-pass filter and / or determining the acceleration and the inertia of the moving elements. In order to compensate for the inertia described above, a low-pass filter can be used in an implementation that is easy to implement. This can be applied to the variables used for control and / or regulation, such as the size and / or the change in size and / or intermediate values calculated during the control and / or regulation, in order to control the dynamics of a control and / or regulation system to reduce. Alternatively, the accelerations, in particular rotational accelerations, and the moments of inertia, for example the waves and / or wheels assigned to the shafts and / or the drive units, can be determined. Based on these values, an exact correction around the

Torque component, which is not available by the acceleration and / or deceleration, are made.

The invention further relates to a drive device of a motor vehicle, in particular for carrying out the method according to the preceding Embodiments, with at least two each driven by a shaft drive device waves, wherein a total drive torque of the motor vehicle substantially corresponds to the sum of applied to the waves shaft moments. It is provided that, due to a size and / or change in the size of one of the shaft moments, a control and / or regulation of the other shaft moments takes place. The drive device has at least two different or similar drive units. The drive device may be, for example, a hybrid drive device with at least two different drive units. It is advantageous if at least one electric machine and at least one internal combustion engine are assigned to the hybrid drive device.

The invention further comprises an electronic control unit, in particular for carrying out the method and / or the control of a drive device according to the above statements, for controlling and / or regulating shaft torque of the at least two waves each driven by a shaft drive device, wherein a total drive torque of the motor vehicle substantially the sum of and the waves applied to the shaft moments. It is envisaged that a size and / or change in the size of one of the shaft moments is taken into account in the control and / or regulation of the remaining shaft torques. The control unit thus serves to implement the described method and / or the regulation / control of the drive device. This can be designed as a hybrid drive device and, for example, as already stated, at least one internal combustion engine and at least one electric machine have.

Brief description of the drawings

The invention will be explained in more detail below with reference to the embodiments illustrated in the drawing, without any limitation of the invention. Show it: Figure 1 is a schematic representation of a motor vehicle with a

Drive and with two by means of shaft drive devices driven shafts, and

Figure 2 is a diagram showing the coordination of adjacent to the waves

Wave moments describes.

Embodiment (s) of the invention

FIG. 1 shows a schematic illustration of a motor vehicle 1 with a drive 2 which drives a first shaft 4 and above wheels 5 by means of a first shaft drive device 3 and a second shaft drive device 6 which drives wheels 8 via a shaft 7. The first shaft drive device 3 has an electric machine 9, an internal combustion engine 10, and a transmission 11. The electric machine 9 and the internal combustion engine 10 are coupled together by suitable means. The unit of electrical machine 9 and internal combustion engine 10 is connected via a coupling 12 with the gear 11, which performs a speed or torque ratio and is operatively connected on its output side with the shaft 4. The shaft 4 is thus drivable via the combination of the electric machine 9 and the internal combustion engine 10. The second shaft drive device 6 has an electric machine 13, which is connected via a coupling 14 with a transmission 15 designed as a simple transmission 16 with the shaft 7. The shaft 7 is thus drivable via the electric machine 13. The electric machine 13 is further connected via a power electronics 17 to a serving as an energy storage 18 traction battery 19. It can be noted that the first shaft drive device 3 having the electric machine 9 and the engine 10 constitutes a hybrid drive device 20. The wheels 5 and 8 are in communication with a background, not shown, on which the motor vehicle 1 can move. The wheels 5 and 8 or the first shaft drive device 3 and the second shaft drive device 6 are thus in operative connection with each other via this base. This means that the shaft moments generated by the first and the second shaft drive devices 3 and 6 to the Summing Gesamtantriebsmonnent the motor vehicle 1. The shaft moments can be positive or negative. It can be provided, for example, to drive the motor vehicle 1 by means of the internal combustion engine 10, while the electric machine 13 is operated in a generator mode and thus the traction battery 19 is charging. The electric machine 9 is designed as a belt starter generator 21. About this, the internal combustion engine 10 can be started and during an operation of the internal combustion engine 10 power for an unillustrated electrical system of the motor vehicle 1 are generated. The sum of the applied to the two wheels 5 moments corresponds to that of the first

Shaft drive device 3 generated shaft torque, the sum of the applied to the two wheels 8 moments generated by the second shaft drive device 6 shaft torque. The gears 11 and 16 contain axle differentials, not shown. In most driving situations, half of the shaft torque is split between the two wheels, even at different wheel speeds. A deviating distribution may result if the axle differential has a blocking effect. Alternatively, instead of the electric machine 13, two single electric machines may be used, each of which drives one of the wheels 8. One of a driver of the motor vehicle 1 or not shown

Driver assistance system predetermined, possibly for comfort reasons filtered target drive torque is divided into the shaft moments of the two shafts 4 and 7.

FIG. 2 shows a diagram which illustrates the coordination of the shaft torques applied to the shafts 4 and 7. At an input 22 of a calculation unit 23, a target drive torque M _SO ιι is specified. This is dependent, for example, on a request of the driver of the motor vehicle 1 or the driver assistance system. The calculation unit 23 divides the target drive torque into shaft desired torques M _A i, _S oiι and M _A 2, soiι. The former is provided at a first output 25, the latter at a second output 24 of the calculation unit 23. The two values M _A i, _S oiι and M _{A2, SOII} serve as input to a limiter unit 26. These are at an input 27 a size M _A i, _m ιn (minimum torque of the shaft 4 and the shaft drive device 3), at an input 28th one Moment M _A i _{, max} (maxinnnnonnent the shaft 4 or the shaft drive device 3), at an input 29 a moment M _A 2, min (minimum torque of the shaft 7 and the shaft drive device 6) and at an input 30 a moment M _A 2, max (Maximum torque of the shaft 7 5 and the shaft drive device 6) provided. The limiter unit 26 has a first limiter 31, a second limiter 32 and a third limiter 33. The inputs 27 and 28 are connected to the first limiter 31, the inputs 29 and 30 respectively to the second and the third limiter 32 and 33. The second output 24 of the io calculation unit 23 is connected to the second limiter 32. The input's signal M _A 2, soiι is therefore limited with the signals present at the inputs 29 and 30 signals M _A2, _m ιn and M _A2, _m ax. At an output 34 of the second limiter there is therefore a limited moment between (inclusive) M _A 2, min and M _A2 , _m ax. At a node 35, a difference between

15 calculated this limited moment and the moment M _A2 , _S oiι. At a further node 36, this calculated difference is added to the torque M _{AI, SOII present} at the first output 25 of the calculation unit 23. The result of this addition is applied to the input 37 of the first limiter 31. The nodes 35 and 36 form a first cross-connection 38.

This serves in the manner described to add the difference between the input and output torque of the second limiter 32 to the voltage applied to the first output 25 of the calculation unit 23 moment. The first limiter 31 limits the value resulting from the addition, which is applied to the input 37, with those at the inputs

25 27 and 28 applied values M _A i, _mιn and M _A i, _max . The result of this limitation is output at the output 39. At a node 40, analogous to the node 35, a difference between the input and output of the first limiter 31, that is, the values present at the input 37 and the output 39, calculated. This difference is on

30 adds a node 41 to the moment present at the output 34. The nodes 40 and 41 represent another cross-connection 42. The signal resulting from the addition at the node 41 is used at the input 43 as input to the third limiter 33. The signals M _A2 , mm and M _A2 , _max applied to the inputs 29 and 30 are also applied to this. Of the

Limiter 33 limits the signal present at the input 43 to the two latter values. The limited value is present at the output 44. The present at the output 39 signal is referred to as M _A i, soiι, hm and present at the output 44 signal as M _A 2, soiι, hm. These wave output torques M _A i, _S oiι and M _A 2, soiι are so in the limiters 31, 32 and 33 with the respective minimum _moments M _A i _{, Mιn} and M _A2 , min and the maximum moments M _A i, _max and M _A2 , _m ax limited. The cross connections 38 and 42 ensure that the torque component (difference between the unlimited and the limited shaft nominal torque) which can not be represented on a shaft is transferred to the respective other shaft. The output 39 of the first limiter 31 is connected to a calculation unit 45. The minimum / maximum _moments M _A i, _mιn , M _A2 , _m ιn, M _A i, _max , M _A2 , _m ax be on the basis of provided by the shaft drive devices 3 and 6 torque ranges, Abregelungen, emergency / error states of the shaft drive devices 3 and 6, switching operations in the transmissions 11 and 16 and determined by vehicle dynamics systems. In this case, translations of the gear 11 and 16 are observed. In the case of several drive units of a shaft drive device 3, 6, the individual unit limits must be combined, that is to say, for example, both a torque range of the electric machine 9 and the internal combustion engine 10 are taken into account. For example, falls the electric machine 13 of the second

_{Shaft drive device} 6 due to a fault condition suddenly off, so jump the minimum _moment M _{A2 min} and the maximum _torque M _{A2 max of} the second shaft drive _device 6 to zero or on the rotation of the shaft drive devices 6 resulting friction or loss torque. The transverse connection 38 then has a torque component of the first shaft drive device 3 which can not be represented on the second shaft drive device 6. The calculation unit 45 divides the limited wave desired torque M _A i, _SO ιι, ι _ιm in moments M _B KM, I and M _e ι, i. The former represents a moment of the internal combustion engine 10, the latter a moment of the electric machine 9. In this case, the calculation unit 45 takes into account a present gear ratio of the transmission 11. The connected electric machine 9 and internal combustion engine 10 deliver the torque generated by them to the transmission 11. This ensures a speed / torque conversion and outputs the translated torque to the shaft 4 and the wheels 5 from. The from the implementation of the transmission 11th resulting moment is referred to as wave moment M _A i. In most driving situations, this moment M _A i divides evenly on the wheels 5, so that V2 M _A i is transmitted to the ground at both wheels 5. In contrast, the signal at the output 44 is used as input to a calculation unit 46. This calculates from the value M _A 2, soiι, hm a moment M _e ι, 2, which is to be generated by the electric machine 13. The translation of the transmission 16 is taken into account by the calculation unit 46. The electric machine 13 thus generates the moment M _e ι, 2, which is converted by the gear 16 to the shaft torque M _A2 . This moment M _A2 is applied to the shaft 7 and the wheels 8. As described above, in most driving situations of the motor vehicle 1 the moment M _{A2 is} evenly distributed to the wheels 8, so that the moment V2 M _A2 is present on both wheels.

In the quasi-steady-state operation, that is at low rotational accelerations on the rotating parts of the aggregates of the shaft drive device 3 (electric machine 9, the internal combustion engine 10, transmission 11, clutch 12) corresponds to the shaft torque M _A i approximates to the limited shaft torque M _A i, _SO ιι, ι _ιm - At high spin accelerations portions of the generated moments are required to accelerate or retard the inertial masses of the rotating parts. The shaft torque M _A i deviates from these inertial components of the limited wave desired torque M _A i, _SO ιι, ι _ιm from. The same applies to the shaft drive device 6; the shaft torque M _A2 deviates from the limited Wellensollmoment M _A 2, _S oiι, hm at high spins. In particular, when driving dynamics systems or switching operations in the gears 11, 16, the limited Wellensollmoment M _A i, _SO ιι, ι _ιm or the limited Wellensollmoment M _A 2, _S oiι, hm influence, high rotational accelerations may be present. For example, when a vehicle dynamics system raises the limited shaft desired torque M _A i, _SO ιι, _ιm by increasing the limit M _A i, _mιn to avoid locking the wheels 5 and to accelerate the rotating parts of the units of the shaft drive devices 3. The effective wave moment M _A i then differs from the limited shaft torque M _A i, _SO ιι, ι _ιm to the inertia of play. In a further development of the embodiment, corresponding inertial components in the transverse connections 38 and 42 are corrected, so that only the effective ones Moment differences are transferred to the other wave. In the simple case, the output signals of the nodes 35 and 40 can be low-pass filtered to reduce the dynamics. An exact correction can be achieved by determining the rotational accelerations and the moments of inertia of the rotating parts. A similar correction can also be made to compensate for inertia of the wheels or a drive dynamics of the drive units.

The behavior of the limiter unit 26 can be adjusted via the variables applied to the inputs 27, 28, 29 and 30. Normally, the moments M _A i, mιn, M _A 2, max, M _A 2, min, and M _A2 , max are set so that the shaft drive devices 3 and 6 are in a normal operating range, that is not in an overload range and / or in an unfavorable operating point. If the normal operating range changes on a shaft drive device 3 or 6 or if there is a limitation of one of the shaft torques applied to the shafts 4 and 7, the minimum and maximum torques can be adjusted such that the shaft drive devices 3 and 6 are at least temporarily in an overload range and / or or unfavorable operating point may be operated. In this way, a sudden change of a total drive torque of the motor vehicle 1, which is composed of the shaft torque M _A i and M _{A2 of} the shafts 4 and 7, can be prevented. In this way, the safety of the motor vehicle 1, in particular with a present limitation, increased. The limitation of one of the shaft drive devices 3 and 6 may be present, for example, due to torque ranges, Abregelungen, emergency conditions, switching operations and / or inputs of vehicle dynamics systems. In this case, it may happen that the total drive torque of the motor vehicle 1, ie M _A = M _A i + M _A2 , of the predetermined target drive torque M _{A, so} n, which is applied to the input 22, deviates. In this case, it should be ensured that the total drive torque of the motor vehicle is changed continuously and / or gradient-limited, so that no sudden changes in the total drive torque can occur.

Claims

claims

Anspruch [en] A method of operating a drive (2) of a motor vehicle (1) which has at least two shafts (4, 7) which can each be driven by means of a shaft drive device (3, 6), wherein a total drive torque of the

Motor vehicle (1) substantially the sum of the waves (4,7) applied shaft torque corresponds, characterized in that a size and / or a change in the size of one of the shaft moments is taken into account in a control and / or regulation of the remaining shaft torque.

2. The method according to claim 1, characterized in that as at least one of the shaft drive devices (3,6) an internal combustion engine (10) or an electric machine (9,13) or a hybrid drive device (20) with at least two different

Drive units, in particular an electric machine (9) and an internal combustion engine (10), or a hydraulic machine is used.

3. The method according to any one of the preceding claims, characterized in that the total drive torque substantially corresponds to a predetermined by a driver of the motor vehicle (1) and / or a driver assistance system target drive torque.

4. The method according to any one of the preceding claims, characterized in that in a deviation of the total drive torque from the target drive torque due to a limitation of at least one shaft torque, the deviation of the total drive torque is continuous and / or gradientenbegrenzt.

5. The method according to any one of the preceding claims, characterized in that after elimination of the limitation, the total drive torque is adjusted continuously and / or gradientenbegrenzt to the target drive torque.

6. The method according to any one of the preceding claims, characterized in that for continuous and / or gradientenbegrenzten change of the total drive torque at least one of the shaft drive devices (3,6) is operated in an overload range and / or in an unfavorable operating point.

7. The method according to any one of the preceding claims, characterized in that for continuous and / or gradient-limited change of the total drive torque, the total drive torque is filtered and / or changed according to a ramp.

8. The method according to any one of the preceding claims, characterized in that the change of the total drive torque is such that an amount of the total drive torque is less than an amount of the target drive torque and / or the total drive torque is approaching zero.

9. The method according to any one of the preceding claims, characterized in that the target drive torque is filtered.

10.Verfahren according to any one of the preceding claims, characterized in that for at least one of the shafts (4,7) a minimum torque and / or a maximum torque is set.

11.Verfahren according to any one of the preceding claims, characterized in that the minimum torque and / or maximum torque as a function of one of the shaft drive device (3.6) provided torque range and / or a reduction of one of the shaft drive devices (3,6) and / or a Run-flat / fault condition and / or a switching operation in a transmission and / or values of a

Vehicle dynamics control is set.

12. The method according to any one of the preceding claims, characterized in that the torque range of Shaft drive device (3,6) is determined in dependence on drive units of the hybrid drive device (20).

13. The method according to any one of the preceding claims, characterized in that the operation of the shaft drive device (3,6) is allowed in an overload range and / or in an unfavorable operating point by means of adjusting the minimum torque and / or maximum torque.

14. The method according to any one of the preceding claims, characterized in that in the control and / or regulation of the remaining shaft moments inertia of moving elements, in particular of the shafts and / or of the shafts associated wheels and / or the drive units, is taken into account.

15. The method according to any one of the preceding claims, characterized in that the inertia is taken into account by using a low-pass filter and / or the acceleration and inertia of the moving elements are determined.

16. Drive device (20) of a motor vehicle (1), in particular for carrying out the method according to one or more of the preceding claims, with at least two each by means of a shaft drive device (3.6) driven shafts (4,7), wherein a total drive torque of the motor vehicle (1) essentially the

Sum of the waves (4,7) applied shaft torque corresponds, characterized in that due to a size and / or change in the size of one of the shaft moments, a control and / or regulation of the remaining shaft torque occurs.

17. Electronic control device, in particular for carrying out the method according to one or more of the preceding claims and / or for controlling a drive device (20) according to claim 16, for controlling and / or regulating shaft torque of at least two each by means of a shaft drive device (3,6 ) drivable Shafts (4,7), wherein a Gesamtantriebsmonnent of the motor vehicle (1) substantially equal to the sum of the waves (4,7) applied shaft torque, characterized in that a size and / or change in the size of one of the shaft moments in the control and / or regulation of the remaining shaft torque is taken into account.