DE102009013409A1 - Drive chain particularly for motor vehicle, has drive unit controlled by control unit with multiple cylinders and drive shaft, and condition value of dual mass flywheel is read in controller - Google Patents

Abstract

The drive chain has a drive unit controlled by a control unit with multiple cylinders and a drive shaft. A condition value of the dual mass flywheel is read in the controller. The condition value of a detection of misfire takes place over the entire speed range of the drive unit. An independent claim is included for a method for controlling a drive unit with multiple cylinders in a drive chain of a motor vehicle.

Description

The The invention relates to a powertrain and a method of operation the same in particular for a motor vehicle with a controlled by a control unit drive unit with a drive shaft and with this in operative connection and from this powered dual mass flywheel.

Known are arrangements in a drive train in which an internal combustion engine is controlled by means of an engine management system. In arrangements This type of so-called misfiring can not be ruled out. A combustion misfire is an event where combustion occurs the air-fuel mixture in a cylinder of the internal combustion engine completely or partially absent. If none or only partial Combustion occurs, the cylinder makes no or less Combustion work and there will be no or less combustion moment built up.

The Occurrence of misfiring can be for various reasons to have. For gasoline engines, for example, a faulty Ignition system or worn spark plugs cause that combustion misfires arise. The ignition energy is enough in this case, stop completely adding the mixture inflame. Another cause of misfiring represents about too lean an air-fuel mixture. The supplied Fuel quantity is too low to be inflamed here. Even a poorly distributed mixture can lead to that combustion misfires arise. In diesel engines are particularly at cool temperatures in the warm-up phase frequently Misfiring on.

by virtue of a misfire breaks the engine speed partially noticeable, which negatively affects the smoothness of the engine effect. The unburned mixture finally passes over the exhaust valves in the exhaust system. This leads to a Afterburning of the mixture in the hot catalyst and thereby to an additional strong increase in temperature. Due to the high temperatures of the catalyst ages much faster and can even be destroyed. Have misfiring additionally negative influence on the exhaust gas behavior. at faulty ignition behavior becomes unburned hydrocarbons released. But also with disturbances of the fuel injection increases the emission of hydrocarbons (HC) and carbon monoxide (CO), since lowering the temperature of the combustion chamber walls and the exhaust gas takes place. Because with a misfire the Oxygen has not completely reacted, the supplies Lambda probe a "faulty" signal. this has As a result, the lambda control of the engine is a wrong air-fuel mixture calculated and thereby in the remaining cylinders following a too rich fuel-air mixture is injected. Farther become disproportionate after a combustion misfire high levels of noxious gases such as hydrocarbons and carbon monoxide emitted, which pollute the environment and cause injury or destruction of the catalyst can result. Especially at high speeds, these shares are very high, so that a detection of misfires especially at high speeds up to the maximum speed particularly desirable is.

The Detection of combustion misfires can be done via a measurement the cylinder pressure take place. Furthermore, so-called knock sensors proposed. Another possibility is the measurement of the ion current in the cylinder. Such detection methods are expensive. Alternatively, the crankshaft speed is determined by means of a speed sensor determined on the crankshaft. Changes by a misfire this is significant.

are however, on the crankshaft driven elements, such as Ancillaries, clutch and / or transmission components such as Two-mass flywheels attached, which are time-dependent can initiate dynamic return moments in the crankshaft this because of a short-term misjudgment of the crankshaft speeds due to this highly dynamic introduction of momentary torque changes on the crankshaft a faulty interpretation of the currently applied Motor torque result, so that in the following the engine management system the internal combustion engine controls incorrectly. This can be, for example over torques on driven elements and thus too an overuse with premature failure of this, lead to loss of comfort and increased fuel consumption.

task is therefore a powertrain and a related Method for detecting combustion misfires of a drive unit to propose, despite time-varying and dynamic introduction of moments of return driven elements an improved Detection of combustion misfires the drive unit allows. Furthermore, there is the task of the expense of such a correction in terms of cost, simple and inexpensive.

The The object is achieved by a method for operating a drive train with a control unit controlled by a drive unit with a drive shaft and with this in operative connection and solved by this powered dual-mass flywheel, wherein at least one state value of the dual mass flywheel in the control unit is stored and with the at least one state value indexed Motor torque is determined. According to the invention thereby from the indexed moment the mass moment of the drive unit eliminated and based on the remaining moment contributions detected a misfire. Likewise, the solution is done the task by the appropriate powertrain using of the designated method.

Under a control unit is a computing unit with a Microprocessor and a memory to understand, where in the arithmetic unit performed the necessary steps to control the drive unit and corresponding in a corresponding input unit Sensor signals for characterizing the driver's desired torque and more input variables recorded and with the help of the motor data stored in an engine map, for example calculated and in an output unit to the affected units, such as depending on the output signal actuated Injectors or injection pumps, is issued. Further Parameters, such as the engine speed or more on the CAN bus Present data are usually used to control the Internal combustion engine also read. Usually is this control unit with additional control units, For example, to control the brakes, any existing automated clutch or a control unit for control an optionally existing automated transmission or other control units, connected. It can also be beneficial be, several control units to optimize the space and / or the electrical components or computing power of the control units to one or the number of total number of ECUs reduced number together to combine and vote.

According to the invention in the control unit for controlling the drive unit at least a state variable of the dual mass flywheel is read and possibly saved. The state variable is then used in the algorithms for controlling the internal combustion engine used, so using this at least one state variable an adapted to the dual mass flywheel behavior of the internal combustion engine is achieved. For example, by the at least one state variable the compensation of a disturbing to the drive unit impact event resulting from the dual mass flywheel, at least partially.

Under a drive unit in the context of this invention is an aggregate to understand that requires external control and has a drive shaft whose speed in dependence can be varied by a driver's request. Preferably, in this sense a reciprocating engine with a crankshaft as well also a rotary engine with a suitably designed Drive shaft to be a drive unit. In the wider sense meets the inventive embodiment of an electric motor with a Drive shaft, which disturbed by a driven element and therefore readjusted by means of the state variable must become.

The Dual mass flywheel is on the one hand with a mass against rotation connected to the drive shaft and inelastically takes a torque on the other hand has an elastic coupled secondary mass, especially in the dynamic Operating state transmitted torque to the drive shaft can and thus to a failure of the control of the drive unit can lead. In particular, according to the invention the speeds, angles of rotation and / or derived therefrom sizes the two flywheel masses, namely of input and output part of the dual mass flywheel to set up the state space and used to determine the state variables. alternative or additionally, by other elements in the Powertrain example torque converter, transmission components such as waves or gears or hybrid Electric machines introduced elements at the launch be taken into account by state variables.

Also other components in the drive train in conjunction with the vehicle body or drive wheels can under given circumstances to back torques in the crankshaft and thus to the fault lead the control of the internal combustion engine and therefore as Input variables of the state space serve. for example may already have a different adhesion of the wheels a lane to lead back moments. On such Processes applicable state variables can determined and also to compensate for disturbances be processed in the control unit.

Furthermore, driven elements by ancillaries such as fuel pumps, power generators, air conditioning compressors and the like or belt drives, camshafts, Verstellinrichtun gene and valve trains and the like may be formed.

• – Motorsteuerung mittels Motormomenten,
• – Signal, Validierung und Adaption eines echtzeitfähigen Motormomentmodells,
• – Zylindergleichstellung,
• – Leerlaufregelung,
• – Antiruckregelung,
• – Lastschlag-Regelung,
• – Optimierung von Einspritz- und Zündwinkel,
• – Optimierung der Einspritzmenge,
• – Detektion und Adaption von Voreinspritzmengen,
• – Regulierung und Adaption des Motorstarts,
• – Regulierung und Adaption des Anfahrvorganges,
• – Bestimmung von Reibmomenten einer Kupplung zwischen Brennkraftmaschine und Getriebe,
• – Funktionsüberprüfung des Motorsteuergeräts,
• – allgemeine Motordiagnose,
• – verbesserte Regelung von Aggregaten im Antriebsstrang, beispielsweise Kupplung, Wandler, Getriebe aller Arten, Schlupfregelung der Kupplung, Schlupfregelung der Antriebsräder,
• – Steuerungsvorgänge bei Hybridanwendungen,
• – Getriebeschutz,
• – Ermittlung des Brennraumdrucks einzelner Zylinder beziehungsweise Ermittlung eines dynamischen Mitteldrucks der Zylinder,
• – Analyse von Bauteilen von Antriebsaggregaten, wie beispielsweise Zweimassenschwungrad (Positionsbestimmungen von Bauteilen eines Zweimassenschwungrades).

In addition to the detection or detection of combustion misfires, the following typical control tasks of the control unit, for example by an advantageous drive train and the associated method can be improved:

• - engine control by means of engine torque,
• Signal, validation and adaptation of a real-time engine torque model,
• - cylinder equalization,
• - idling control,
• - antiruck control,
• - load-stroke regulation,
• - optimization of injection and ignition angle,
• - optimization of the injection quantity,
• - detection and adaptation of pre-injection quantities,
• - regulation and adaptation of the engine start,
• - regulation and adaptation of the starting process,
• Determination of friction moments of a clutch between internal combustion engine and transmission,
• - functional check of the engine control unit,
• - general engine diagnosis,
• Improved control of powertrain units, such as clutch, converter, transmission of all types, slip control of the clutch, slip control of the drive wheels,
• Control processes in hybrid applications,
• - transmission protection,
• Determination of the combustion chamber pressure of individual cylinders or determination of a dynamic mean pressure of the cylinders,
• - Analysis of components of drive units, such as dual mass flywheel (position determinations of components of a dual mass flywheel).

Especially it may be advantageous if, when several state variables are present these are summarized in a so-called state space. Here, under a state space is a number of state variables to understand, which are each dependent on the time and characterize a transmission system. With the help of this State variables can be used for the control the transmission system necessary outputs depending on also time-dependent input variables in the assumption of known initial values determined or be calculated.

Physically considered describe the state variables the energy content of a system, so in addition to the equations for the dependence of the output quantities of the state variables, the input variables and the initial values for the number of state variables correspondingly many differential equations can be formed, the dynamic behavior of the state variables play.

From a vector perspective, in the case of linearity and time invariance of the system, the two systems of equations can be regarded as matrix systems whose individual coefficients can be represented and calculated in the elements of matrices. For a more detailed explanation of the treatment of state space models in the measurement and control technology is on "Otto Föllinger, Control Engineering - Introduction to Methods and their Application, 8th Edition" directed.

With Help the dependent created in state space in this way Data from state, input and output variables For example, a state space model can be developed based on model data and / or empirically obtained data of the dual mass flywheel identified and validated. Voices state space model and these data match, can a timely compensation of the engine torque of the drive unit, that disturbed by the influence of the driven element will be achieved, at least in part.

Advantageously, the input variables used are data that are easily measurable. While measuring momentum for torque correction of the drive unit is comparatively complicated, it has been found that use of rotational speeds can be particularly advantageous. Thus, by inversion of the state space model from rotational speeds output quantities in the dimension of a moment can be obtained. In an advantageous manner, additional model data of the drive unit are recorded during the identification of the driven element, so that the corrected engine torque can be obtained directly as output variables. The corrected engine torque can in this way one - as above Hand illustrated by typical application examples - a large number of applications are used on the one hand in the operation of a vehicle with a drive unit as well as for the diagnosis of engine and / or powertrain behavior.

When the application of the proposed has particularly advantageous Method for a drive train with a drive unit such as an internal combustion engine with a crankshaft and a dual-mass flywheel mounted thereon having a primary part, which is accommodated on the crankshaft and a secondary part proved, with the two parts stored and opposed the force of a spring device against each other and limited the predetermined speed of the crankshaft relative to each other are rotatable. The secondary part usually has one Friction clutch, by means of which the secondary part and so that the drive unit to the subordinate in the direction of action transmission can be coupled. It is understood that also modified embodiments, in which an electric machine interposed in parallel or in series is, as well as all forms of power take-offs covered by the invention become. The dual-mass flywheel is used for vibration isolation the generated by the combustion process of an internal combustion engine Oscillations. In certain operating conditions, in particular at a relaxation of the compressed spring means, that is Dual mass flywheel capable of returning moments to the internal combustion engine and by an unrecognized, short-term speed change the control behavior of the controller for controlling the To disturb internal combustion engine, resulting in said effects can lead.

The Dual mass flywheel can be used as spring device bow springs and / or short spiral springs to form one or more damper stages have, wherein the springs also by means of other power storage as Rubber elements can be combined and on different diameters can be arranged.

Of the Spring device can be superimposed on a hysteresis device be, in conjunction with the spring device for damping contributes. The hysteresis device can by two or several, standing in wet or dry rubbing contact each other Friction partners be formed, which are made of axial or radial to each other lying, advantageously biased friction surfaces can be formed. Advantageously, a centrifugal force dependent Frictional contact during a relative rotation of the two Parts, each with a predeterminable mass with a turn have forming moment of inertia, be generated by that extending over a circumference springs, for example Bow springs, of a part, for example, the secondary part taken along and at the outer radius under centrifugal force against a radial support of the other part, for example the primary part, be pressed and thus at a relative rotation of the form a centrifugal force-dependent hysteresis force on both parts, under which the two parts are difficult to rotate against each other. Further advantageous embodiments of friction devices For example, against each other axial braced friction partners one of which is on the primary side and the other on the secondary side rotatably or with a backlash is arranged. Technically vibration The dual-mass flywheel acts as a low-pass filter between the crankshaft and gear input shaft with a typical attenuation the oscillation amplitude associated with a phase shift the oscillation frequency.

As already mentioned above, when the state space is transformed into a vector equation system, a system of linear equations must be present. In general, differential equations of system models, such as a dual mass flywheel, are not linear. However, if the controlled system has an approximate linear behavior in a certain work area, the differential equations can often be linearized for this sufficiently small selected work area. From this, linear state differential equations and output value equations can be established. The behavior of dual mass flywheels, in particular due to the bow spring characteristic with speed-dependent hysteresis, biased springs and clearance angle of the hysteresis, may be non-linear. According to the invention, therefore, the dual mass flywheel is linearized by the behavior of the dual mass flywheel is functionally represented by physical relationships and then differentiated to the operating points to be used. Particularly advantageous may be a further method of linearization, by means of which an approximated linear model is used and a range of validity is established in which an error occurring does not exceed a predetermined limit. The selection of such a model can be piece-specific. For example, in extreme cases, models can be designed as "black-box models" which very well approximate the input and output behavior and require no prior knowledge of kinematic processes. At the other extreme, the modeling of a state space can be done in such a way that the kinematics of the system are used exactly descriptive equations (white-box model). The subsequent identification then provides the desired compensation, independent of the model chosen, by choosing the variables of the state space such that there is an optimized match between the empirically or model-based data of a dual-mass flywheel and the input and output variables of the state space model is achieved.

In a particularly advantageous embodiment, a simplified Model used for a dual-mass flywheel one between two masses, namely one connected to the drive shaft Primary mass and a secondary mass connected to the output, includes effective linear spring / damper element. The State variables of this linear model are correct here with the nonlinear state variables of a in sufficient manner. It is understood that the choice of the model depending on the type of dual-mass flywheel is and that depending on the design of Zweimas senschwungrades - and in a broader sense also for every driven element - the corresponding models (black box models, gray box models, white box models) can be optimized in an advantageous manner.

For the simplified model, for example, the following relationships arise: J pri · Ω. pri = M pri - c · (α pri - α sec ) - d · (ω pri - ω sec ) (1) and J sec · Ω. sec = -M sec + c · (α pri - α sec ) + d · (ω pri - ω sec ) (2).

Where J _pri and J _{sec are} the moments of inertia of the primary and secondary flywheels, M _pri and M _{sec are} the primary and secondary mass of the dual-mass flywheel, c is the stiffness of the spring elements acting between the two masses, and d is the torsional damping of the damping elements between the two masses. α _pri and α _{sec are} the absolute angles of the primary and secondary mass relative to the crankshaft and their time-derived quantities of the angular velocities ω _pri and ω _sec and the angular accelerations ω. pri and ω. sec ,

If the relative angle between the primary and secondary side and the rotational speeds of both flywheels are defined as state variables, the following state vector results:

Equation (1) and equation (3) result in the following state space representation:

In a particularly advantageous embodiment, only an evaluation based on the signals of the velocities ω _pri and ω _{sec is} carried out to determine the indicated engine torque, so that the output vector y is given the following shape:

It It is understood that in the case of other measures such as the detection of accelerations, angles, and Torques of the output vector can take different shape.

If a state space such as shown above is created, the identification is made for the dual-mass flywheel to be compensated. According to the invention, a selection of physical input variables is determined for this purpose, which are sufficient for determining the estimated output variables. It has been found that a selection of irrelevant and redundant data leads to unnecessarily complex calculations and the lack of relevant input variables leads to a lack of unambiguousness of the output variables can.

Advantageous can be, for example, if from a model calculation and / or data from empirical experiments, an outlier test, for example, a media filter. Farther It may be advantageous to use the input variables too filter, for example by means of a Butterworth low-pass filter. In such frequency-selective filters is a cutoff frequency predetermined, passed through to the signals almost unchanged become. Higher-frequency signal components are strongly attenuated. It is understood that adapted to an occurring noise in the input variables additionally or alternatively further advantageous filters can be used.

to further identification of the dual-mass flywheel must be the order of the linear state space model. advantageously, has the order for the elementary dual mass flywheel n = 3, where the ordinal number is the number of state variables yields, proven, by means of which an ideal spring / damper element can be described. The determination of the order must be in the Rule for each driven element and the basis lying model separately.

To The determination of the system order usually has to continuous-time system into an equivalent time discrete System to be converted. That is, the example of the dual mass flywheel is due to the entered data a state space representation which then converts into a time-discrete state space model must become. For this purpose, a numerical Evaluation of the general solutions of the state differential equation or a numerical integration of the state differential equation using numerical integration methods. To determine the discretized Model and its sizes can subsequently apply a so-called least-square estimator, where, from a number of n measurements, the distances between set the output variables, preferably minimized become. The execution of the routine then leads to the parameters c, d, Jpri, Jsek defined in equation (4), that is, the dual mass flywheel with its real behavior is mapped to the model, it is identified. A subsequent one Validation of the underlying model can, for example, thereby done that with the obtained parameters the model at given Calculated rotational irregularities and with a real Behavior of a dual mass flywheel at the same rotational irregularities is compared. At this point can be attached to the model Corrections are still to be made if there are major deviations.

One In this way created model of a driven element can are now stored in the control unit, and corresponding Output variables can be in the engine control be introduced. Using the example of the dual-mass flywheel is an estimate of the primary or secondary Speed of the respective flywheels by specification of engine or Load moments take place. As a rule, torques are in a motor vehicle measurable only with a comparatively high expenditure, so that after the inventive idea an inversion of the state space model is beneficial. At the inversion then post the input variables of the inverted system the Speeds of primary and secondary flywheel while the output quantities are torque values of the engine or load torque values. This way you can by means of simple sensors, for example by means of speed sensors, at the primary and secondary flywheel that induced motor torque can be determined. It is therefore possible the motor torque output as a setpoint compensate for this induced motor torque so that the influence of the dual mass flywheel on the engine is at least partially eliminated can be. It is understood that such an inverted Model previously checked for invertibility and should then be validated again. It can that from the powertrain to the secondary side of the DMF acting load can be determined in an analogous manner, creating an estimate of the load torque can be achieved at the ZMS.

An advantageous embodiment of the invention is in addition to the compensation of the disturbed by the behavior of a dual mass flywheel engine torque a stationary reconstruction of the engine torque for cylinder equalization. For this purpose, it may be necessary to extend a so-called confidence interval, in which trusted data are determined and calculated, of the model by applying the dual-mass flywheel by means of so-called local linear models (LoLiMoT). The confidence interval describes the work area around the local identification work point, in which the model still provides sufficiently good results. By using local linear neuro-fuzzy models, complex modeling problems are broken down into many smaller and therefore simpler subsystems, which in turn can be described by linear submodels. Be aware of the application and implementation of the above-mentioned filter systems and the LoLiMoT model U. Kiencke / H. Jäkel "Signals and Systems", 3rd edition Verlag Oldenbourg directed.

To the reconstruction of the engine torque (indicated engine torque) can this invention for the detection of misfiring be used. It stands thereby one of the influences the driven element independent or a more compensated with respect to its influences Torque value available.

For example can misfires from the general formulas derived for the calculation of the indicated engine torque MMotor by using an additional speed sensor placed on the output side of the driven element, so that the influence of the driven element on the engine torque can be determined or estimated. For example be in a driven element in the form of a dual mass flywheel determines the speed of the primary and secondary side and as inputs to the state space model entered and according to above description the indexed engine torque MMotor is estimated. From the indexed Engine torque MMotor can be determined by the following Embodiment Determine combustion misfire.

The indexed engine torque MMotor, rek is at low speeds from the gas torque MGas, the mass torque MMass, where the mass moment MMass is the moment of reciprocating in the cylinder liners piston to understand the valve torque MVentil and the friction torque MReib together. Dividing the engine torque into its individual moments, the result is: M engine = M gas - M measure - M Valve - M friction - M KW (6)

The misfires are inventively detected on the work done of the individual cylinders. For this purpose, equation (6) is integrated over a cylinder-related segment. In a four-cylinder engine is integrated from top dead center (TDC) to bottom dead center (UT), ie over 180 ° crankshaft angle, the bottom dead center of the i-th cylinder corresponds to the top dead center of the i + 1-th cylinder. This results in:

This results in the work of the cylinder i: M Motor, i = M Gas i - M Mass, i - M Valve, i - M Friction, i - M KW, i (8th)

The Valve torque MV valve over 180 ° crankshaft angle is mean free. At low speeds is the mass moment MKW negligible. Likewise is in a stationary Operating point the mass moment MMass averaging, so that the two Working WVentil, i and WMass, i the cylinder i become 0 and the Work WKW can be neglected.

The Gas moment MGas is composed of compression moment MK and Expansion moment ME and the combustion moment MVerb. Analogous to The valve and mass moments are compression and expansion moments almost mid-value, so that the resulting Work can also be neglected.

If a combustion misfire of the cylinder i occurs, the combustion energy WVerb, i is less than an expected value or equal to zero. For the sake of clarity, a negligible combustion energy WVerb, i is assumed in the exemplary embodiment and, for the work of cylinder i, equation (8) results in: W Motor, i - W Friction, i (9)

A combustion misfire can now be recognized if the work WMotor, i of the cylinder i falls below a predetermined limit ε:

The Barrier ε can be set so small that possibly occurring individual cylinder inequalities and associated collapse of a cylinder not be recognized as a misfire. On the other hand, the Barrier ε advantageously set so large that also not complete burns reliable be recognized.

to advantageous evaluation of combustion misfires can be provided be that after falling below the barrier ε such a called flag or a counter is started, the evaluated by a software routine implemented in the control unit becomes. For example, after a single or after a predetermined number of misfires a warning signal output, an error memory activated and / or compensation the incomplete or incorrect combustion takes place. Such Compensation can be done via cylinder compensation methods, so that with appropriate processing of the barrier ε or said flags or counters a cylinder compensation method started or operated extended by this information can.

To In an advantageous embodiment, the barrier ε can be multi-level be. By evaluating the steps thus formed, a qualitative Statement about the combustion takes place. For example, let by classifying the incineration work WVerb, i the individual cylinder i in a stage "proper Combustion "," incomplete combustion "and" failed Combustion "derive different measures. An evaluation of the frequency in the different classes of the single cylinder can allow a judgment, whether a warning is issued, a workshop must be visited and / or whether engine management measures to improve a recognized state can be done by, for example Air and / or fuel supply to be changed.

at an increase in the speed of the crankshaft increases the mass moment MKW with the crankshaft speed square, so that the Work WKW compared to the other sizes dominated. This has the consequence that misfiring does not detected more significantly and optionally at a desired Cylinder equalization is no longer sufficient for a cylinder equalization can be used. It is therefore proposed over the entire speed range or at the beginning of the fault Detection of misfiring the procedure to change that after the determination of the indicated engine torque in the next Step eliminates the crankshaft-specific mass moment MKW is continued as shown above, with equation (6).

The invention is based on the 1 and 2 explained in more detail. Hereby show:

1 a sequence of control with negligible mass moment M _KW ,

2 an example of a dual mass flywheel explained creation of a state space model and

3 a sequence of a control taking into account the mass moment M _KW .

In the 1 is an exemplary sequence for the control according to the invention 1 shown. In block 2 becomes a setpoint for the control 1 which can be calculated and output as an initial value from a motor controller. In the case of an internal combustion engine, the desired value may be the desired torque which a driver prescribes by means of the accelerator pedal. Accordingly, this desired torque depending on other parameters, such as engine characteristics, gear engaged gear, operating condition of the vehicle, road conditions and the like can be adjusted. In block 3 becomes the setpoint 2 applied to a controlled system, which may include the internal combustion engine and downstream parts such as a clutch, a dual mass flywheel or drive train components such as ancillaries and subsequent transmission. Using the example of a dual-mass flywheel, the target torque delivered to the internal combustion engine is disturbed, in particular in addition to other disturbance influences by other components of the drive train through the two-mass flywheel by its torque-dependent rotation of the two masses against each other, so that according to the invention for compensation of the disturbance in the block 5 a state space model is integrated to compensate for the disturbances.

The creation of a state space model is under 2 explained in more detail. To operate the state space model are from the controlled system 3 Input variables determined and processed in the state space model. In accordance with the invention, input quantities can be all quantities that are available to the control unit as detection data, for example. For example, the controller on a so-called CAN bus are available, namely data such as speeds, accelerations, current and voltage values and the like. To compensate for the behavior of the dual mass flywheel, it may be particularly advantageous to resort to signals that detect the rotational speed of the primary and secondary mass, with their derived variables such as speed accelerations and angular velocities can be advantageous for evaluation.

After passing through the state space model 5 be through this in the block 6 Output variables that are read out and via a suitable signal path 7 to correct the setpoint 2 can be used. It is understood that such a control routine can be calculated serially or in parallel with other control routines in a control unit, for example by means of a microprocessor.

By way of example of a typical driven element in the form of a dual mass flywheel, the creation of a state space model will be described 5 of the 1 in 2 explained in more detail.

As a basis for the mathematical and physical description of a dual mass flywheel on the one hand in block 10 Model data are used, which are obtained from calculation programs, with corresponding simulation data of the real dual-mass flywheel are used as a basis. On the other hand, alternatively or additionally in block 11 experimental data in block 12 provided data set for the corresponding dual-mass flywheel, said data can be obtained from test bench tests with a real dual-mass flywheel.

From the assessment of the data in block 12 will be in block 13 developed a state space model that maps the dual mass flywheel in the conditions specified for a state space. For example, linear equation systems must be available for the mathematical treatment of the state space.

With the help of in block 12 existing data and additionally in block 15 existing data of a motor model, such as maps of an internal combustion engine, that in the state space 13 The two-mass flywheel located in the state space is identified so that the greatest possible approximation between real measured data of the dual-mass flywheel depending on fluctuating moments of the internal combustion engine and a real behavior of the dual-mass flywheel results in the same engine conditions.

If the dual mass flywheel is identified, it will be in the subsequent block 16 validated. The validation determines the system accuracy of the state space and determines the boundary conditions of the applicability of the model. For validation in block 16 can also get motor data from block 15 be used.

In order to obtain output variables which match their dimension with the desired value and at the same time are based on simple input variables, it may be particularly advantageous in block 17 to perform a so-called inversion. Originally, state space models are set up in energy units, whereby input variables in the dimension of moments are input and a corresponding behavior of the dual mass flywheel results in differential rotational speeds of the two flywheel masses. In order to avoid a cumbersome determination of measurable moments in a real environment such as in a motor vehicle, it is particularly in the case of determining disturbances of a dual mass flywheel advantageous in block 13 modeled state space in block 17 to invert. This means that the corresponding rotational speeds or their derived variables of the dual-mass flywheel are now used as input variables for the state space model as input variables, and thus motor torques or disturbance torques induced as output variables are available. It is understood that such an inverted model should also be checked for mathematical function (preferably stability) and validated.

That in block 18 After execution of the previous procedures available model is called state space model 5 in corresponding control loops according to 1 brought in.

3 shows a sequence 20 a control of a drive unit such as internal combustion engine 21 for the detection of combustion misfires with an optionally made cylinder compensation regulation taking into account the mass moment MKW in the form of a block diagram. The internal combustion engine 21 contains a not separately shown engine control unit, in which the individual control routines can be implemented and processed by the processor unit provided therein. Due to the predetermined Control parameters are the internal combustion engine 21 under appropriate firing of the cylinder, for example by injectors a drive torque MBR to the dual mass flywheel 22 from. This transmits a moment MZMS, f on the gearbox 23 with the downstream drive wheels. Due to the elastic properties of the dual-mass flywheel 22 Drive torque MBR and torque MZMS differ, f inevitably.

Furthermore, there are moments of return of the drive train in the form of a load torque ML from the transmission 23 on the dual mass flywheel 22 and from this, according to its elastic properties, a return torque MZMS, r to the internal combustion engine 21 transmitted, which affects the effective moment of the internal combustion engine. As explained in the general description part, the influence of the dual-mass flywheel 22 on the internal combustion engine 21 by means of the determination of an indicated engine torque by means of a state space model and the engine torque is corrected promptly. Another advantage is the determination of the indicated engine torque through its use in the present process 20 for the detection of combustion misfires. For this purpose - as explained above - the indexed moment Mind is the output of the state space model in block 24 certainly.

The input variables are the rotational speeds nprim, nsek of the dual-mass flywheel 22 , which as a state space model in block 24 deposited, identified and linearized. In addition to the use for corrective control of the internal combustion engine 21 the indexed moment becomes Mind the block 25 supplied, in which the mass moment MKW is eliminated. The indexed moment Mind reduced by the mass moment MKW will be in the block 26 initiated. There are misfires, for example, according to the in 1 described scheme 1 detected and in the form of control variables x1, x2 to the internal combustion engine 21 forwarded.

1

control routine

2

block for setpoint formation

3

block a controlled system

4

block for reading input variables

5

block for the state space model

6

block for reading the output variables

7

signal line

10

block for model data

11

block for experimental data

12

block for dataset ZMS

13

block for state space

14

block for identification

15

block for data of the engine model

16

block for validation

17

block for inversion

18

block for model integration

20

procedure

21

Internal combustion engine

22

Dual Mass Flywheel

23

transmission

24

block

25

block

26

block

M _BR

drive torque

M _ind

indexed moment

M _KW

mass moment

M _load

load torque

M _{ZMS, f}

moment

M _{ZMS, r}

rear moment

n _prime

rotation speed

n _sec

rotation speed

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited non-patent literature

• - "Otto Föllinger, Control Engineering - Introduction to Methods and their Application, 8th Edition" [0018]
• - U. Kiencke / H. Jäkel "Signals and Systems", 3rd edition Verlag Oldenbourg [0037]

Claims (19)

Driveline for a motor vehicle with a controlled by a control unit driving unit having a plurality of cylinders and a drive shaft, and a with this is operatively connected to and driven by this two-mass flywheel, characterized in that at least one state value of the dual mass flywheel is read in the control unit and with the at least one state value a detection of combustion misfires over the entire speed range of the drive unit takes place. Drive train according to Claim 1, characterized that several state values are combined in a state space become. Drive train according to one of the claims 1 or 2, characterized in that a einzuregelndes, by Properties of the dual-mass flywheel with a disturbance torque acted induced motor torque of the drive unit means a compensation value determined from the at least one state value at least partially reconstructed. Drive train according to Claim 3, characterized that the reconstructed indexed engine torque is timed becomes. Drive train according to one of the claims 1 to 4, characterized in that the dual mass flywheel means of the at least one state value as a state space model analytically is detected. Drive train according to claim 5, characterized in that that in the state space model of the dual mass flywheel a model the drive unit is integrated. Drive train according to Claim 6, characterized that the analytical detection from data of a modeled dual mass flywheel he follows. Drive train according to claim 5, characterized in that that analytical capture from experimentally determined data of the driven element takes place. Drive train according to one of the claims 2 to 8, characterized in that in the state space the movement of the dual mass flywheel characterizing input variables entered and characteristic for determining the indicated engine torque Sizes are formed and output. Drive train according to Claim 9, characterized that at least one input variable is a speed is. Drive train according to one of the claims 5 to 10, characterized in that the state space model inverts becomes. Drive train according to one of the claims 1 to 11, characterized in that the dual mass flywheel mounted on the drive unit and one with the drive shaft related primary and one with a downstream one Transmission by means of a coupling connectable secondary side is formed. Drive train according to one of the claims 9 to 13, characterized in that as input variables at least the speeds of the primary and secondary sides be used. Drive train according to one of the claims 9 to 13, characterized in that a non-linearized Behavior of the dual mass flywheel is linearized. Drive train according to Claim 14, characterized that the linearization is done by non-linear equations of motion be differentiated at a given operating point. Drive train according to one of the claims 1 to 15, characterized in that for each cylinder the Combustion energy is determined from the indicated moment. Drive train according to claim 16, characterized in that falls below the work of a Cylinder below a predetermined value, a flag, a counter and / or a fault memory is activated. Drive train according to claim 16 or 17, characterized characterized in that prior to the determination of the combustion energy a speed-dependent mass moment of the drive unit is eliminated. Method for controlling a drive unit with a plurality of cylinders in a drive train of a motor vehicle with a driven element characterized by the combination following features: - at least one state variable the driven element is stored in a control unit; - using the at least one state variable becomes the one Reaction of the driven element on the drive unit considered indicative engine torque determined; - using The indicated engine torque becomes the work of a cylinder during determined a work cycle; - using the for each cylinder specific work is a detection of a misfire, by comparing the work with a given barrier.