DE102005035211A1 - All-terrain vehicle drive section controlling method, involves combining moment difference of drive wheels or equivalent operation factor of vehicle drive section to weighted moment difference that is dependant on operation condition - Google Patents

Abstract

The method involves adjusting the transmission ability of switching units by a dynamic module (M3) based on moment difference of different vehicle wheels. An operation factor of the vehicle drive section is determined by functional blocks. A coordination module (M4) combines the moment differences or the equivalent operation factor of the vehicle drive section to a weighted moment difference that is dependant on an operation condition.

Description

The The invention relates to a method for controlling a vehicle drive train according to the Preamble of claim 1 further defined type.

From the DE 103 44 972 A1 For example, a drive train of a four-wheel drive vehicle and a method for controlling and regulating a drive train are known. The drive train is embodied with at least two drivable vehicle transverse shafts or drive axles of the vehicle, with a main transmission arranged between a drive machine and the vehicle axles for displaying various ratios and with three controllable and controllable friction clutches. A first clutch is arranged between the main transmission and a first vehicle transverse shaft. A second clutch and a third clutch of the drive train are each arranged between an axle drive and a drive wheel of the second vehicle transverse shaft. The transmission capabilities of the clutches are each adjustable via an actuator, wherein a drive torque of the drive machine between the drivable vehicle transverse waves in dependence of the set transmission capabilities of the clutches can be distributed. In addition, the proportion of the drive torque supplied in the vehicle transverse direction between the two drive wheels of the second vehicle transverse shaft as a function of the adjusted transmission capabilities of the second and third clutch with variable degrees of distribution can be distributed to the second vehicle transverse shaft.

With the known all-wheel system thus has the possibility of a drive torque actively distributed in the vehicle transverse and vehicle longitudinal direction in such a way that driving dynamics can be acted on the system vehicle. Depending on the type of intervention, this requires a more or less comprehensive operating strategy, the under circumstances with an engine management system and an ESP system.

are all three clutches of the drive train open, is the moment flow interrupted between the output of the vehicle and the engine, as compared to running with a rear axle lock drive trains present there is no axle differential in the area of the vehicle rear axle, which a basic distribution of the drive torque of the prime mover between the drive wheels Take over the second vehicle transverse shaft can. For this reason, the mechanical properties of a Achsdifferenzials in the area of the second vehicle transverse shaft through one in a control unit deposited functional software via to represent the second and third clutch.

moreover it is to influence the driving dynamics of a with the above Powertrain trained vehicle provided, depending the current driving situation that of the prime mover Applied drive torque targeted between the two vehicle transverse waves and the two drive wheels to distribute the second vehicle transverse wave.

adversely However, it is that put to the powertrain system different functional requirements are not always at the same time in full Scope be implemented and under certain circumstances disadvantageous until for mutual restriction influence each other. Furthermore is intended for influencing the driving dynamics control and Control system very extensive, through a high maintenance marked and expandable only to a limited extent.

Of the The present invention is therefore based on the object, a method for controlling a vehicle driveline set, which has a simple structure, by a small Maintenance is characterized and in a simple manner expandable or adaptable to different powertrain systems is.

According to the invention this Task with a method for controlling a vehicle drive train according to the characteristics of claim 1.

The inventive method for controlling a vehicle drive train, which is arranged either with two each between a drive wheel of a drivable vehicle transverse shaft and a drive axle of a vehicle and a transverse distributor gear arranged frictional shift elements for variably distributing the vehicle transverse shaft supplied drive torque in the vehicle transverse direction between the two drive wheels or with at least a first and formed with a frictional engagement element means for variably distributing a drive torque of a prime mover in the vehicle longitudinal direction between two drivable transverse vehicle waves and two further each arranged between a drive wheel of one of the vehicle transverse waves and a Querervergetriebs frictional shift elements for variably distributing the second vehicle transverse shaft supplied proportion of the drive torque in the vehicle transverse direction zwi is formed the two drive wheels, is easily adaptable to various powertrain systems of vehicles, characterized by low maintenance and characterized by a simple structure.

This is achieved by the transfer capabilities the switching elements in dependence different Raddifferenzmomente the Antriebsrä the vehicle or equivalent operating variables of the Drivetrain can be adjusted, which has several drive train specific executed function blocks be determined. Thus, the inventive method as a whole function a functional structure in which the individual function blocks or Modules are clearly definable and each seen separately for themselves can be developed and maintained. Interfaces between the function blocks or modules are such definable that the function blocks or modules are easily interchangeable, for different Powertrain systems can be used and that the procedure is characterized by a clearly structured structure. Furthermore is the overall function of driving depending on the respective application only with little effort variable, preferably only to adjust the functional blocks substantially are and the interfaces continue to be used unchanged.

Furthermore be the determined Raddifferenzmomente the drive wheels or the equivalent ones Operating variables of the Drivetrain each for each drive wheel over a coordination module to an operating state-dependent weighted Raddifferenzmoment or an equivalent operating size of the drive train united, whereby the disadvantage known from the prior art, that different functional requirements, each one individually To positively influence a driving dynamics of a vehicle, join simultaneous consideration possibly like that mutually influence the driving dynamics of a vehicle is negatively influenced, is easily avoided.

As a general rule The modular structure of the method according to the invention offers the possibility of making changes the configuration in the powertrain without a complete new development the functional connections to realize because the existing range of functions by low adaptation measures each adaptable to a new powertrain system.

Further Advantages and advantageous developments of the invention result from the claims and with reference to the drawings in principle Embodiment.

It shows:

1 a highly schematic representation of a drive train of a four-wheel drive vehicle, which is operated by the method according to the invention;

2 a highly schematic block diagram of the control of the drive train according to 1 used method according to the invention;

3 a trained as driving dynamics module function block of the method according to the invention;

4 in the block diagram according to 1 shown and executed as a slip control module function block;

5 a more detailed representation of a executed as a basic distribution module function block;

6 a the basic distribution module, the slip control module and the vehicle dynamics module downstream coordination module of the method according to the invention and

7 a clutch slip management following the coordination module in the course of the procedure.

1 shows a vehicle drive train 1 a four-wheel drive vehicle in a highly schematic representation of a drive unit 2 and a main gearbox 3 includes, where the main gear 3 Any known per se from the practice of transmission can be. The drive unit 2 is at the in

1 illustrated embodiment designed as an internal combustion engine and may for example be carried out in an advantageous development as an electric motor.

Between a first drivable transverse vehicle shaft 4 or drive axle of the vehicle, which in the present case represents a vehicle front axle and in a known manner on each vehicle side with at least one drive wheel 4A . 4B connected, and the main gearbox 3 , which is intended to represent various translations, is a first clutch k_VA a transfer case 9 arranged in a longitudinal drive train I_HA. The first clutch k_VA is between the main gear be 3 and a facility 6 for compensating differential speeds between the drive wheels 4A and 4B the first vehicle transverse wave 4 arranged, the device 6 in the present case is designed as a transverse transfer case known per se.

Furthermore, between an axle drive 7 , via which a in the direction of a second drivable transverse vehicle shaft 5 or drive axle of the vehicle guided part of the drive torque of the internal combustion engine 2 in the direction of two drive wheels 5A . 5B the second vehicle transverse shaft 5 is feasible, and each one of the drive wheels 5A . 5B the second vehicle transverse shaft 5 a second clutch k_HA_L or a third clutch k_HA_R arranged in transverse distributor strands q_HA_L and q_HA_R.

About the cross transfer case 6 there is a possibility of driving wheels 4A and 4B the first vehicle transverse wave 4 independently of each other corresponding to the different path lengths of the left and right lane to drive at different speeds, whereby one of the first vehicle transverse shaft 4 supplied proportion of the drive torque symmetrical and thus yaw moment free between the drive wheels 4A and 4B the first vehicle transverse wave 4 can be distributed in the vehicle transverse direction.

In contrast, the transverse distribution of the second vehicle transverse shaft 5 supplied proportion of the drive torque via the variably adjustable transmission capabilities of the two clutches k_HA_L and k_HA_R performed, wherein preferably one of the two clutches k_HA_L and k_HA_R is operated in a synchronous state and the other clutch k_HA_R or k_HA_L is operated slipping to power loss in the To keep switching elements as low as possible. In this case, depending on the transmission capability of the slipping-operated clutch k_HA_L or k_HA_R of the second vehicle transverse shaft 5 a transverse distribution degree of the second vehicle transverse shaft 5 supplied proportion of the drive torque between 0% to 100%, based on one of the two drive wheels 5A or 5B , feasible.

In this case, the degree of lateral distribution is related to the activation of the second clutch k_HA_L and the activation of the third clutch k_HA_R in such a way that the entire portion of the drive torque, which is the second vehicle transverse shaft 5 is supplied to each drive wheel 5A or 5B is supplied to 100%, which is the synchronously operated clutch k_HA_R or k_HA_L downstream when the other coupling k_HA_L or k_HA_R the transverse distribution strands q_HA_L and q_HA_R is operated with such a reduced transmission capability that no torque is transmitted via this coupling.

The three clutches k_VA, k_HA_L and k_HA_R of the vehicle drive train 1 are in the present case designed as controllable and controllable frictional multi-plate clutches whose transmission capabilities are known per se and in 1 not shown actuator 8th are adjustable. The use of the three clutches k_VA, k_HA_L and k_HA_R offers the possibility of a drive torque of the prime mover 2 or a transmission output torque of the main transmission 3 variable and as needed in the vehicle longitudinal direction between the two drivable transverse vehicle shafts 4 and 5 as well as in the area of the vehicle transverse shaft 5 in the vehicle transverse direction between the two drive wheels 5A and 5B to distribute.

2 shows a highly schematic block diagram of the method according to the invention, by means of which the in 1 illustrated vehicle drive train 1 is controllable such that via the two switching elements k_HA_L and k_HA_R a basic distribution of the second vehicle transverse wave 5 supplied proportion of the transmission output torque of the transmission 3 can be performed in the same manner as over a conventionally executed axle differential. Furthermore, by means of the method as a function of a respective current driving situation or a current operating state of the vehicle, various requirements for an operating strategy through a targeted redistribution of the transmission output torque of the main transmission 3 in the vehicle drive train 1 be implemented in such a way that the driving dynamics of a vehicle can be adapted as needed to the current operating state of the vehicle to improve driving comfort and to improve driving safety.

For this purpose, the method for controlling the vehicle drive train 1 at the in 2 illustrated embodiment, multiple and interconnected via interfaces function modules M1 to M7, which form a clearly defined functional structure. The function modules M1 to M7 represent subareas that can be developed independently of one another and are linked to one another via defined interfaces in such a way that the modules can be exchanged without costly modification of the interfaces and can be reused in different projects. This makes it possible in a simple way to adapt the method according to the invention to different drive train concepts by changing the overall functional scope, wherein an extension of the overall functional scope can be implemented without difficulty.

About the function modules or functions Blocks M1 to M3 are dependent on various input variables, which are preferably operating state parameters of the vehicle, such as speeds, engine torque, steering wheel angle, yaw rate and acting on the vehicle longitudinal and lateral accelerations, wheel differential torque Δ m_rad_i the drive wheels 4A to 5B or equivalent operating variables of the vehicle drive train 1 determined. Subsequently, the output variables of the functional blocks M1 to M3 representing wheel differential torques Δm_rad_i of the drive train-specific function blocks M1 to M3 are fed to the function module M4 designed as a coordinator module as input variables and in the coordination module M4 for each drive wheel 4A . 4B . 5A . 5B to an operating state-dependent weighted wheel difference torque Δ m_rad_g_i or an equivalent operating size of the vehicle drive train 1 united.

The operating state-dependent weighted wheel difference torques m_rad_g_i are fed to the function module M5 designed as a clutch slip management as an input variable and converted into control values for the inrush module 1 illustrated actuators 8 for setting the transmission capabilities of the switching elements k_VA, k_HA_L and k_HA_R converted, representing the switching elements each with the necessary for setting the required for the implementation of the requested driving dynamics wheel moments m_rad_4A, m_rad_4B and m_rad_5A and m_rad_5B transmission capabilities.

The function modules M6 and M7 are designed as so-called intelligent control devices whose interface consists of a physical variable, ie in the present case to be set to the switching elements to be transmitted torque, which is independent of the actuation. This offers the advantage that temperature-related, wear-related and design-related influences in the area of the functional module M6, which the switching element k_VA of the transfer case 9 and, in the area of the function module M7, via which the switching elements k_HA_L and k_HA_R are controlled, are taken into account and do not have to be taken into account in the area of the function modules M1 to M5 upstream of the function modules M6 and M7 in the method sequence.

In the present case, the function block M1 embodied as a basic distribution module essentially has requirements for the operating strategy, such as a so-called ride-on of the clutch torques as a function of the transmission output torque of the main transmission 3 , a prevention of a high-revving engine due to low transmission capabilities of the switching elements of the vehicle drive train 1 and an optimization of the tire force potential taking into account the uprising, longitudinal and lateral force, taken into account. In particular, the latter requirement is implemented in the present case taking into account the Kamm circle, which indicates in approximate form a ratio of the currently transmitted cornering forces to still transferable acceleration forces or vice versa at different slip angles and camber angle of the drive wheels.

By way of the function module M2 designed as a slip-control module, a torque support is essentially carried out in the case of occurring tire slip events, ie druchdrehenden wheels, in particular the switching elements k_HA_L and k_HA_R at spinning drive wheels 5A and 5B be closed, with a simultaneous spinning of all drive wheels 4A to 5B is counteracted by a corresponding engine intervention.

The Initiation of an active yawing moment due to asymmetric longitudinal force distribution in the vehicle powertrain, a support of cornering behavior by an appropriate torque distribution, d. H. a so-called Steer through targeted propulsion, and a response to oversteer or understeering driving behavior by a driving dynamics control, is determined by the present as driving dynamics module function module M3 available posed.

In addition, however, in the vehicle powertrain also tensions are to be prevented and a coordination of the switching elements with respect to a fully closed state and a slip operation by a corresponding interaction of the function modules M1 to M7 are made possible to achieve a high level of ride comfort, avoid critical driving situations and component damage in the vehicle drive train 1 to prevent.

In 3 is the vehicle dynamics module M3 according to 2 presented in detailed form. In a step S1, a desired yaw rate ψ_soll is first determined as a function of a steering wheel angle φ and the vehicle speed v_fzg via a one-lane vehicle model, which is fed as input quantity to a second step S2, in which an actual yaw rate ψ_act determined via a sensor device is taken into account Control deviation can be determined. Subsequently, in a step S3, the control deviation between the measured actual yaw rate ψ_ist and the calculated target yaw rate ψ_soll are derived according to time, and in steps S4 and S5 the wheel difference torques Δm_rad_i (M1) for the drive wheels 4A to 5B as a function of the control deviation determined in step S2 Chung and derived in step S3 derivation of the control deviation preferably determined with different gain, which form the input values for the coordination module M4.

4 shows a preferred embodiment of the slip control module M2 by means of which control deviations between an actual slip s_ist and a desired slip s_soll of the switching elements k_VA, k_HA_L and k_HA_R are determined. In this case, the actual slip values s_act of the switching elements k_VA, k_HA_L and k_HA_R are dependent on a transmission output rotational speed n_g_ab of the main transmission 3 of the vehicle drive train 1 and the rotational speeds n rad of the drive wheels 4A to 5B determined. In parallel, the setpoint slip values s_setpoint of the switching elements k_VA, k_HA_L and k_HA_R are determined in a step S7 using a calculation algorithm, in this case based on the Ackermann relationship, for a kinematic cornering, which are preferably expanded by values corresponding to estimated longitudinal slip values of the drive wheels 4A to 5B are equivalent. Subsequently, in each case in steps S8, S9 and S10 control deviations between the actual slip values s_act and the setpoint slip values s_set of the switching elements are determined and for the drive wheels 4A to 5B A wheel difference torque Δm_rad_4A (M2), Δm_rad_4B (M2), Δm_rad_5A (M2), Δm_rad_5B (M2) is determined in each case by means of PID controllers R1, R2 and R3 as a function of the control deviations determined in steps S8 to S10. Since the switching elements k_HA_L and k_HA_R in spinning drive wheels 5A and 5B close, is used in the control not on the wheel speed differences but on the clutch differential speeds, wherein the clutch differential speeds in the aforementioned manner in each case from the transmission output speed n_g_ab and the wheel speeds n from the drive wheels 4A to 5B be determined.

5 shows a more detailed representation of the basic distribution module M1 according to 1 , about which a basic distribution of the drive wheels 4A to 5B in each case via the switching elements k_VA, k_HA_L and k_HA_R operating state-dependent supplied torques is determined. In this case, in a step S11 a wheel load estimation is performed from a static weight distribution Gvt of the vehicle and vehicle-engaging dynamic longitudinal and lateral acceleration components a_fzg_l and a_fzg_q, which is fed to a step S12 as an input value. In step S12, in addition to the wheel load estimate from step S11, in addition, depending on the transmission output torque m_g_ab of the main transmission 3 , an actuation speed v_p of the accelerator pedal and an actuation speed v_lk of the steering wheel, the wheel difference torque m_rad_i (M1) for the drive wheels 4A to 5B certainly.

Here, the transmission output torque m_g_ab in the basic distribution module M1 from the drive torque of the prime mover, a status of the main transmission 3 of the vehicle drive train 1 and preferably a converter overshoot of a hydrodynamic torque converter, which is proportional to the wheel load estimate between the drive wheels determined in step S11 4A to 5B is distributed.

In 6 a more detailed representation of the coordination module M4 of the inventive method is shown in which the weighting of the determined via the function modules M1 to M3 wheel difference Moments Δ m_rad_i (M1), Δ m_rad_i (M2) and Δ m_rad_i (M3) takes place as a function of a current driving condition, the Based on various operating state parameters, ie in this case the current steering wheel angle φ, the vehicle speed v fzg and the lateral acceleration a_fzg_q of the vehicle via a so-called state graph ZM4 is performed.

Of the State graph ZM4 includes several by predefined transient conditions linked together Control units RE1 to REi for controlling predefined operating states of the Vehicle, each depending the aforementioned determined operating condition parameters, d. H. the steering wheel angle φ of the vehicle speed v_fzg and the lateral acceleration a_fzg_q.

This means that the coordination module M4 receives the requirements of the three functional modules or functional blocks M1 to M3 and from this as a function of a current driving situation for each drive wheel 4A to 5B In a step S13, a single request Δ m_rad_g_i to be forwarded is generated. The underlying mechanism can be based on a hard switching between the individual specifications of the function modules M1 to M3, a weighted addition of all specifications or on an optimization algorithm with criteria to be defined, such as a sporty driving behavior, a consumption-oriented driving behavior or the like. The focus here is that the individual requirements mentioned above for the operating strategy achieve their functional goals to the greatest possible extent, without conflicting with each other.

Furthermore, in the coordination module M4 for reducing a control deviation in the area of the function blocks M1 to M3, a feedback routine for the function blocks M1 to M3 is implemented to what extent their wheel difference torque request tions Δ m_rad_i (M1) to Δ m_rad_i (M3) have each found in the determined via the coordination module M4 weighted Raddifferenzmomenten Δ m_rad_g_i input because without such a feedback routine in the control system integrated controller with increasing operating time may determine a high control deviation and high controller outputs to generate.

This in 1 only schematically illustrated clutch slip management M5 is in 7 shown in more detail, wherein in the clutch slip management M5 in a step S14, a so-called relative and absolute overpressure of the switching elements k_VA, k_HA_L and k_HA_R depending on the transmission output torque m_g_ab of the main transmission 3 is determined. This is a so-called running away the speed of the prime mover 2 due to fluctuations in the drive torque of the prime mover 2 and the transmission capabilities of the switching elements k_VA, k_HA_L and k_HA_R prevented. The term relative overpressing of the switching elements is understood here to mean a value of the transmission capability of the switching elements which is proportional to the transmission output torque m_g_ab by which the transmission capabilities for avoiding slip operation are set to be higher in magnitude than would actually be required to transmit the respectively applied torque.

Since the relative overpressure of the switching elements, for example, at a transition of the vehicle drive train 1 from a train operation to a coasting mode at least in a short time window in a low torque range, this may lead to operating conditions of the switching elements k_VA, k_HA_L and k_HA_R of the vehicle drive train that they do not transmit the applied torques to the desired extent, and undesirably in a slipping operation pass. For this reason, the transmission capabilities of the switching elements k_VA, k_HA_L and k_HA_R with respect to a threshold value of the drive torque of the prime mover are each increased in addition to the relative proportion increased by an absolute proportion, wherein the magnitude increase in the transmission capabilities of the switching elements k_VA, k_HA_L and k_HA_R depending a distribution vector v_vek ascertained as a function of the driving situation via a state graph ZM5 is distributed between the switching elements k_VA, k_HA_L and k_HA_R in a step S15.

This is in all operating ranges of the vehicle drive train 1 ensures that the switching elements, which are to be safely operated in a completely closed state, are displayed with a corresponding overpressure. In this connection, it is pointed out that, in particular to avoid tension in the drive train and the above-described coordination of the clutches with respect to a closed and a slipping operation, the method according to the invention special transition strategies for transferring the switching elements from a fully closed operation in a slipping operation of Can have switching elements and vice versa.

The inventive method for controlling a vehicle drive train described is not on the in 1 illustrated vehicle drive train 1 limited, but can also be found in other powertrain systems due to its functional structure in a simple manner. Thus, it is possible to operate a drive train with the method according to the invention, which instead of the switching element k_VA formed with the transfer case 9 a fixed torque distribution between the first vehicle transverse shaft 4 and the second vehicle transverse shaft 5 has, or is performed only with a Vorderachs- or Hinterachsantrieb, which is executed in each case with the two switching elements k_HA_L and k_HA_R.

1

powertrain

2

Prime mover Internal combustion engine

3

main gearbox

4

first Vehicle cross shaft

4A, B

Drive wheels of first vehicle transverse wave

5

second Vehicle cross shaft

5A, B

Drive wheels of second vehicle transverse shaft

6

Cross transfer case

7

transaxles

8th

actuators

9

Transfer Case

a_fzg_q

lateral acceleration of the vehicle

a_fzg_l

longitudinal acceleration of the vehicle

Gvt

weight distribution

k_VA

first clutch

k_HA_L

second clutch

k_HA_R

third clutch

l_va

Longitudinal distribution powertrain to the front axle

m_g_ab

Transmission output torque of the main gearbox

M1 to M7

function module

n_g_ab

Transmission output speed

q_HA_L

Querverteiler support

q_HA_R

Querverteiler strand

R1 to R3

PID controller

RE1 to REi

controller unit

s

slippage

s is

Actual slip, Actual slip value

S1 to S15

step

s_cmd

Target slip, Target slip value

v_vek

distribution vector

v_fzg

vehicle speed

v_lk

operating speed of the steering wheel

v_p

operating speed the accelerator pedal

ZM4

state graph

ZM5

state graph

φ

steering wheel angle

ψ

yaw rate

ψ_ist

Actual yaw rate

ψ_soll

Target yaw rate

Δ m_rad_g_i

weighted wheel differential

Δm_rad_i

wheel differential

Claims (19)

Method for controlling a vehicle drive train ( 1 ), with two each between a drive wheel ( 5A . 5B ) a drivable transverse vehicle shaft ( 5 ) and a transverse transfer case ( 7 ) arranged frictionally engaged switching elements (k_HA_L, k_HA_R) for variable distribution of the vehicle transverse wave ( 5 ) input drive torque in the vehicle transverse direction between the two drive wheels ( 5A . 5B ) or with at least one first and with a frictional switching element (k_VA) formed device ( 9 ) for variably distributing a drive torque of a drive machine in the vehicle longitudinal direction between two drivable vehicle transverse waves ( 4 . 5 ) and two further each between a drive wheel ( 5A . 5B ) one of the vehicle transverse waves ( 5 ) and a transverse transfer case ( 7 ) arranged frictionally engaged switching elements (k_HA_L, k_HA_R) for variable distribution of the vehicle transverse wave ( 5 ) supplied proportion of the drive torque in the vehicle transverse direction between the two drive wheels ( 5A . 5B ), characterized in that the transmission capabilities of the switching elements (k_VA, k_HA_L, k_HA_R) are dependent on different wheel differential torques (Δm_rad_i (M1), Δm_rad_i (M2), Δm_rad_i (M3)) of the drive wheels ( 4A to 5B ) of the vehicle or equivalent operating variables of the vehicle drive train ( 1 ), which are determined via a plurality of drive train-specific function blocks (M1 to M3), wherein the wheel difference torques (Δm_rad_i (M1), Δm_rad_i (M2), Δm_rad_i (M2,) Δm_rad_i (M3)) of the drive wheels ( 4A to 5B ) or the equivalent operating variables of the vehicle drive train ( 1 ) for each drive wheel ( 4A to 5B ) are combined via a coordination module (M4) to an operating state-dependent weighted wheel difference torque (Δ m_rad_g_i) or an equivalent operating variable of the drive train. Method according to claim 1, characterized in that that the weight of the over the functional blocks (M1 to M3) determined wheel difference moments (Δ m_rad_i (M1) to Δ m_rad_i (M3)) depending a current driving condition, the basis of various Operating state parameter (φ, v_fzg, a_fzg_q) of the vehicle via a state graph (ZM4) is determined. Method according to claim 2, characterized in that that the state graph (ZM4) several more by predefined transition conditions linked together Control units (RE1 to REi) for controlling predefined operating states of the Vehicle, each of which is determined in dependence of operating condition parameters (φ, v_fzg, a_fzg_q) become. Method according to one of claims 1 to 3, characterized that the wheel difference moments (Δ m_rad_i (M1) to Δ m_rad_i (M3)) depending various operating state parameters of the vehicle, the input variables of function blocks (M1 to M3). Method according to one of claims 1 to 4, characterized that the function blocks (M1 to M3) from the coordination module (M4) for reducing a control deviation in the area of function blocks (M1 to M3) a feedback to what extent their wheel differential torque requirements (Δ m_rad_i (M1) to Δ m_rad_i (M3)) are included in the weighted wheel difference moments (Δm_rad_g_i). Method according to one of claims 1 to 5, characterized in that a function block is designed as a basic distribution module (M3), via which the drive wheels ( 4A to 5B ) in each case via the switching elements (k_VA, k_HA_L, k_HA_R) operating state-dependent to be supplied torques are determined. Method according to Claim 6, characterized in the basic distribution module (M3) from a static weight distribution (Gvt) of the vehicle and on the vehicle attacking dynamic Along- and lateral acceleration ratios (a_fzg_q, a_fzg_l), a wheel load estimate is performed. A method according to claim 7, characterized in that in the basic distribution module (M3) from the drive torque of the prime mover, a status of a main transmission ( 3 ) of the vehicle drive train ( 1 ) and preferably a wall a transmission output torque (m_g_ab) is determined proportional to the wheel load estimation between the drive wheels ( 4A to 5B ) is distributed. A method according to claim 8, characterized in that the distribution of the transmission output torque (m_g_ab) in the vehicle transverse direction between the drive wheels ( 5A . 5B ) of the vehicle transverse shaft ( 5 ) is variable in response to an operation of an accelerator pedal of the vehicle and / or in response to an operation of a steering device of the vehicle. A method according to claim 8 or 9, characterized in that the distribution of the transmission output torque (m_g_ab) in the vehicle longitudinal direction between the vehicle transverse waves ( 4 . 5 ) and in the vehicle transverse direction between the drive wheels ( 5A . 5B ) of the vehicle transverse shaft ( 5 ), which are assigned to the two other switching elements (k_HA_L, k_HA_R), in response to actuation of an accelerator pedal of the vehicle and / or in response to actuation of a steering device of the vehicle is variable. Method according to one of claims 1 to 10, characterized a functional block (M2) is designed as a slip-control module, by means of which deviations between an actual slip (s_ist) and a desired slip (s_soll) of the switching elements can be determined. A method according to claim 11, characterized in that the actual slip values (s_ist) of the switching elements (k_VA, k_HA_L, k_HA_R) in dependence of a transmission output rotational speed (n_g_ab) of the main transmission ( 3 ) of the vehicle drive train ( 1 ) and the rotational speeds (n from) of the drive wheels ( 4A to 5B ) be determined. A method according to claim 11 or 12, characterized in that the desired slip values (s_soll) of the switching elements (k_VA, k_HA_L, k_HA_R) are determined by means of a calculation algorithm for a kinematic cornering, which are preferably extended by values corresponding to estimated longitudinal slip values of the drive wheels ( 4A to 5B ) are equivalent. Method according to one of claims 11 to 13, characterized in that for the drive wheels ( 4A to 5B ) is determined by means of PID controllers (R1 to R3) in each case a wheel differential torque representing a correction value (Δ m_rad_i (M2)) as a function of the control deviations. Method according to one of claims 1 to 14, characterized a function block (M1) represents a vehicle dynamics module about the control deviations between a measured actual yaw rate (Ψ_ist) and one preferably over a one-lane vehicle model determined target yaw rate (ψ_soll) of the Vehicle be determined. Method according to claim 15, characterized in that that the wheel difference moments (Δ m_rad_i (M1)) depending the control deviations and the time-derived control deviations preferably be determined with different gain. Method according to one of claims 1 to 16, characterized in that the weighted wheel difference moments (m_rad_g_i) by means of a clutch slip management (M5) in control values for an actuator ( 8th ) for setting the transmission capabilities of the switching elements (k_VA, k_HA_L, k_HA_R), which represent the switching elements (k_VA, k_HA_L, k_HA_R) with the transmission capabilities required for setting the wheel torques. Method according to one of claims 1 to 17, characterized that the transmission capabilities the switching elements (k_VA, k_HA_L, k_HA_R) amount in each case one with respect to the requested transmission capabilities relative proportion and with respect to a threshold value of the drive torque the prime mover increased by an absolute percentage with the relative proportion and the absolute proportion increasing the transmission capabilities the switching elements (k_VA, k_HA_L, k_HA_R) as a function of a via a State graphs (ZM5) distribution vector determined by the situation (v vek) are distributed to the switching elements (k_VA, k_HA_L, k_HA_R). Method according to claim 17 or 18, characterized in that the control values of the clutch slip management (M4) are respectively input variables for control units (M6 and M7) of the actuators ( 8th ) of the switching elements (k_VA, k_HA_L, k_HA_R) represent over which temperature, wear and / or design-related influences on the setting of the requested transmission capabilities of the switching elements (k_VA, k_HA_L, k_HA_R) are taken into account.