DE102018131964A1 - Method and device for preventing an unwanted acceleration of a motor vehicle - Google Patents

Abstract

The invention relates to a method for monitoring a motor vehicle (1) with a drive system, comprising the following steps: - checking a first condition that depends on a speed of the drive system and / or a speed gradient of the drive system, - checking a second condition that of a Measure of a vehicle jerk; - triggering an error reaction which indicates an impending unwanted acceleration of the motor vehicle (1) when the motor vehicle (1) is in a stop state and the first and second conditions are met.

Description

Technical field

The present invention relates generally to motor vehicles and, in particular, to a method for operating an engine system for a motor vehicle, with which undesired accelerations of the motor vehicle can be avoided.

State of the art

The operation of engine systems in motor vehicles is safety-critical, which is why measures for monitoring the proper function are provided as standard. In particular, three-level concepts are customary for monitoring, in which control unit functions are monitored by a torque or acceleration-based monitoring function. In this way, undesired accelerations of a motor vehicle, such as can be caused, for example, by a software or hardware fault in the engine control unit, are prevented.

The monitoring generally triggers an error reaction if the determined engine torque or the determined acceleration of the motor vehicle is not plausible and / or a predetermined, maximum permissible value of the monitored variable is exceeded. These methods enable a sufficiently quick reaction to errors occurring in the normal driving state.

For reasons of tolerance, previous methods for detecting unwanted accelerations use threshold values and detection times which are suitable for driving conditions at higher speeds, but which do not guarantee a sufficiently fast reaction in the event of a fault in the speed range close to standstill. In particular, current monitoring methods require a length of time which is too long, for example in order to prevent a pedestrian who crosses the street immediately in front of the motor vehicle from starting.

From the publication DE 10 2013 107 781 A1 A method for monitoring a motor vehicle is known, an error reaction being triggered according to a stop state monitoring method if the motor vehicle is in a stop state and at least one monitoring-relevant condition is fulfilled that indicates an impending unwanted acceleration of the motor vehicle.

This procedure may in vehicles with a starting clutch or different drive units on one drive axle, be too slow to prevent unwanted acceleration or to stop the vehicle in time. This is mainly due to the fact that discrete threshold values for the speed and the speed gradient are evaluated.

Furthermore, such methods cannot be used in hybrid drive systems since, in the case of a plurality of drive motors, these have temporally different courses of the speeds and the speed gradients due to an interposed electrically controlled clutch. As a result, error detection based on these variables is not possible.

Accordingly, according to DE10 2014 206 491 A1 A method for monitoring a motor vehicle with a drive system with a plurality of drive motors can be provided, wherein according to a performance-based or energy-based stop state monitoring method, an error reaction is triggered when the motor vehicle is in a stop state and at least one performance condition or energy condition that is met on a Current balance of the current mechanical performance or an energy balance of the currently available energies of all coupled drive motors is based.

Disclosure of the invention

According to the invention, the method for monitoring a motor vehicle according to claim 1 and the device, the motor vehicle and the computer program according to the independent claims are provided.

Further advantageous configurations of the present invention are specified in the dependent claims.

• - Überprüfen einer ersten Bedingung, die von einer Drehzahl des Antriebssystems und/oder einem Drehzahlgradienten des Antriebssystems abhängt,
• - Überprüfen einer zweiten Bedingung, die von einem Maß eines Fahrzeugrucks abhängt;
• - Auslösen einer Fehlerreaktion, die eine bevorstehende ungewollte Beschleunigung des Kraftfahrzeugs anzeigt, wenn sich das Kraftfahrzeug in einem Haltezustand befindet und die erste und die zweite Bedingung erfüllt sind.

According to a first aspect, a method for monitoring a motor vehicle with a drive system is provided, with the following steps:

• Checking a first condition which depends on a speed of the drive system and / or a speed gradient of the drive system,
• Checking a second condition, which depends on a measure of a vehicle jerk;
• Triggering an error reaction which indicates an impending unwanted acceleration of the motor vehicle when the motor vehicle is in a stop state and the first and second conditions are met.

The above method enables a quick error reaction for the special case of a suddenly occurring unwanted or faulty acceleration from a standing position or from Speed range close to standstill, such as can occur in front of a traffic light or a zebra crossing, in order to avoid endangering pedestrians in front of the motor vehicle. It is also ensured that the above monitoring method has no undesirable effects on the dynamics in normal driving.

According to a previous approach, speeds and speed gradients of a drive motor are compared with threshold values and / or, in particular in hybrid drive systems, powers of several drive motors, which are determined on the basis of their speeds and speed gradients, are accumulated and compared with a respective permissible threshold value. Special operating situations, in particular the first and MSA start of the combustion engine as the drive motor, in which system-related increased speeds and speed gradients and thus a higher actual power are present, must be considered separately in order to avoid an undesired reaction of the monitoring system and a consequent restriction of availability of the Avoid motor vehicle.

In the case of conventionally driven motor vehicles, in particular in the case of motor vehicles with an internal combustion engine as the drive motor, the current measures are sufficient in the situations mentioned, although here too the consideration of the special operating situations means a relatively high outlay. For hybrid vehicles with multiple drive motors, however, the compromise between robustness and safety of the monitoring system is associated with considerably more effort. In particular, a variant-specific, very precise application of the monitoring method is required, which, due to the large number of variants, entails a high level of complexity and a high outlay for applications and security.

The above method makes it possible, depending on the detection of a vehicle jerk not justified by the driver's request, in addition to monitoring, which is based on a consideration of the speed and / or the speed gradient or performance monitoring, to recognize undesired acceleration from a standstill in an improved manner . Since an increase in the speed or power of the drive motors in relation to the monitoring target to detect unwanted acceleration from a standstill, as is relevant in the case of an actual vehicle movement, the function is made more robust by evaluating the physical vehicle jerk by only adding relevant situations to one Error response.

The vehicle jerk essentially corresponds to a change in the vehicle acceleration over the road (above ground).

The consideration of certain operating situations, such as. B. at a first and MSA start, as is usual with previous monitoring, can be simplified or removed both in function and in the application. By considering the physical vehicle jerk, the severity of the error based on the driver's request can also be determined continuously for a driver's request other than 0. The previous method was only effective if the driver wanted 0, so that the monitoring method can monitor further relevant operating points of the vehicle system and thus increase safety.

Furthermore, the first condition can include checking a speed of the drive system with respect to a predetermined speed threshold value and / or checking a speed gradient of the drive system with regard to a predetermined speed gradient threshold value. In particular, in addition to the monitoring method, a torque or acceleration-based monitoring method can be carried out.

According to a further embodiment, the first condition can check a power of the drive system, which is based on a power balance of the current mechanical powers of one or more coupled drive motors of the drive system, with regard to a power threshold value and / or check a power of the drive system, which is based on an energy balance of the currently provided energies of all coupled drive motors based on an energy threshold.

Furthermore, it can be provided that the method is only carried out when the motor vehicle is in a stop state, it being determined in particular that the stop state is assumed when the speed of the motor vehicle is below a predetermined speed threshold value.

In particular, it can be determined that the holding state is assumed when there is a torque request that is smaller than a predefined torque request threshold value.

Furthermore, the measure of the vehicle jerk can indicate a change in the vehicle acceleration or a vehicle acceleration with respect to the roadway that is determined from the change in the vehicle acceleration.

It can be provided that the second condition comprises checking the degree of the vehicle jerk with respect to a predetermined acceleration threshold value.

In particular, acceleration information about the acceleration of the motor vehicle can be derived and then integrated in order to obtain vehicle acceleration with respect to the road.

• - eine erste Bedingung zu überprüfen, die von einer Drehzahl des Antriebssystems und/oder einem Drehzahlgradienten des Antriebssystems abhängt,
• - eine zweite Bedingung zu überprüfen, die von einem Maß eines Fahrzeugrucks abhängt;
• - eine Fehlerreaktion auszulösen, die eine bevorstehende ungewollte Beschleunigung des Kraftfahrzeugs anzeigt, wenn sich das Kraftfahrzeug in einem Haltezustand befindet und die erste und die zweite Bedingung erfüllt sind.

According to a further aspect, a device for monitoring a motor vehicle with a drive system is provided, the device being designed to:

• to check a first condition which depends on a speed of the drive system and / or a speed gradient of the drive system,
• - to check a second condition which depends on a measure of a vehicle jerk;
• trigger an error reaction which indicates an impending unwanted acceleration of the motor vehicle when the motor vehicle is in a stop state and the first and second conditions are met.

According to a further aspect, a motor vehicle with a drive system and the above device is provided.

Figure list

• 1 eine schematische Darstellung eines Kraftfahrzeugs mit einem Motorsystem mit einem Verbrennungsmotor und einem Motorsteuergerät;
• 2 eine schematische Darstellung einer alternativen Ausführungsform eines Kraftfahrzeugs mit einem Hybridantriebssystem, und
• 3 ein Flussdiagramm zur Veranschaulichung eines Verfahrens zur Überwachung eines Kraftfahrzeugs.

Preferred embodiments of the present invention are explained below with reference to the accompanying drawings. Show it:

• 1 a schematic representation of a motor vehicle with an engine system with an internal combustion engine and an engine control unit;
• 2nd a schematic representation of an alternative embodiment of a motor vehicle with a hybrid drive system, and
• 3rd a flowchart to illustrate a method for monitoring a motor vehicle.

Description of embodiments

1 schematically shows a motor vehicle 1 with a drive system that z. B. from a drive motor designed as an internal combustion engine 2nd consists of a clutch 3rd or a torque converter is coupled to an output train (not shown). The drive motor 2nd is controlled by an engine control unit 4th controlled, in particular based on a torque request from a driver or a driver assistance system (not shown).

A torque request can be made by the driver by operating an accelerator pedal 5 be given. Furthermore, a brake pedal 6 be provided, by the actuation of which the driver signals that he wishes to carry out a braking operation or signals a braking request. Based on the torque request in the form of a driver's desired torque, for example from the accelerator pedal position of the accelerator pedal 5 is derived, the engine control unit determines 4th corresponding control variables or control variables for the drive motor 2nd . In the case of an internal combustion engine as a drive motor 2nd The manipulated variables may include a throttle valve manipulated variable, an injector manipulated variable, a camshaft manipulated variable, a wastegate valve manipulated variable and / or the like. The manipulated variables are determined by the engine control unit 4th engine torque to be provided. In the case of an electric motor as a drive motor 2nd the manipulated variable can be the applied motor voltage or the resulting motor current. The drive motor 2nd can also be designed as a hybrid drive system consisting of an electric motor and an internal combustion engine.

To check the correct functioning of the engine control unit 4th is a monitoring unit 7 provided the control of the drive motor 2nd monitors and triggers an error response in the event of a fault, which the motor vehicle 1 or the motor system of the motor vehicle 1 in a safe state. The monitoring unit 7 is often integrated in the engine control unit 4th is provided and is part of a three-level monitoring concept. The monitoring unit 7 has monitoring functions to a conventional torque or acceleration-based monitoring of the engine control unit 4th to execute.

2nd shows an alternative embodiment schematically a motor vehicle 1 with a hybrid drive system 2nd , otherwise, unless otherwise mentioned below, the motor vehicle of 1 resembles or is similar to this.

The hybrid drive system 2nd can use an internal combustion engine as the first drive motor 21st and an electric drive 22 include as a second drive motor. To control the internal combustion engine as the first drive motor 21st can from the engine control unit 4th Provided manipulated variables include a throttle valve manipulated variable, an injection valve manipulated variable, a camshaft manipulated variable, a wastegate valve manipulated variable and / or the like. The corresponding manipulated variables are determined from one in the engine control unit 4th according to one Torque distribution determined sub-engine torque to be set.

In the case of the electric drive as a second drive motor 22 the corresponding manipulated variable can be the applied motor voltage or the resulting motor current. The second drive motor 22 . The corresponding manipulated variable is determined from one in the engine control unit 4th according to a torque distribution determined partial engine torque to be set for the electric drive.

The torque distribution in the engine control unit is also determined. The torque distribution specifies the proportion of the torque provided by the first drive motor via the drive train to the drive wheels 21st or from the second drive motor 22 provided. The first drive motor 21st and the second drive motor 22 can, for example, via a clutch 23 be coupled to each other, which is usually controlled electrically, depending on whether the first drive motor 21st should or should not provide a partial torque via the drive train.

In the event of an error-related, unintentional acceleration of the motor vehicle that occurs suddenly 1 from a standing position or from a low speed, as can be the case in a driving situation in front of a traffic light or a zebra crossing, the conventional concepts for torque or acceleration-based monitoring do not work. In particular, the detections with the implemented conventional monitoring methods take too long, so that the error reaction in the above driving conditions takes place too late to endanger e.g. B. exclude pedestrians who are in front of the vehicle. The reasons for this are, for example, that the threshold values are set too high and the detection times for the monitoring functions of the monitoring unit are too long 7 .

3rd shows a flowchart to illustrate a in the monitoring unit 7 additionally implemented method for the detection and execution of an error reaction in the event of an undesired acceleration of the motor vehicle 1 .

In step S1 it is checked whether the motor vehicle 1 is in a hold state. The stop state corresponds to a state in which the motor vehicle is at a standstill 1 is present or is traveling at a very low speed. This can be done with an appropriate speed sensor 8th with a drive wheel 9 of the motor vehicle 1 is coupled. Is the speed specification that the engine control unit 4th from the speed sensor 8th receives, less than a predefined speed threshold value (alternative: yes), the method with step S2 continued for further error detection. If this is not the case (alternative: no), then step S1 jumped back since no driving condition relevant to monitoring has been determined.

In step S2 it is checked whether there is a torque request, for example by checking the driver pedal position of the accelerator pedal 5 , by checking the information from a driver assistance system or by determining that the brake pedal 6 has been operated. By comparing a threshold value with a predefined torque request threshold value, a driver's non-existent or only very low torque request can be recognized.

Will in step S2 if there is no or only a small torque request from the driver (alternative: yes), the method is followed by step S3 continued to check for a monitoring-relevant error. continued. If this is not the case (alternative: no), then step S1 jumped back since no driving condition capable of monitoring was determined.

The review in step S3 relates to a first condition that is speed-based and / or speed gradient-based.

1. a) Die Drehzahl des Antriebsmotors 2 ist höher als ein vorgegebener Drehzahlschwellenwert, der Antriebsstrang ist nicht offen, d. h. die Kupplung 3 bzw. ein Drehmomentenwandler bewirkt zumindest eine schlupfende Kraftübertragung zwischen dem Antriebsmotor 2 und dem Antriebsrad 9, und der Gradient der Drehzahl des Antriebsmotors 2 ist größer als ein vorgegebener Drehzahlgradientenschwellenwert.
2. b) Das Produkt aus der Drehzahl des Antriebsmotors 2 und dem Übersetzungsverhältnis eines Getriebes 3 im Antriebsstrang ist größer als ein vorgegebener Antriebsraddrehzahlschwellenwert und die zeitliche Ableitung des Produkts aus der Drehzahl des Antriebsmotors 2 und dem Übersetzungsverhältnis überschreitet einen vorgegebenen Drehzahlgradientenschwellenwert. Hierbei kann für das Übersetzungsverhältnis ebenfalls eine zeitvariable Größe erfasst und bereitgestellt werden, so dass auch ein Schlupf einer Kupplung berücksichtigt werden kann. Insbesondere kann die zeitliche Ableitung des Produkts aus der Drehzahl des Antriebsmotors 2 und dem Übersetzungsverhältnis in eine Beschleunigung des Kraftfahrzeugs 1 umgerechnet werden, die dann bezüglich eines Beschleunigungsschwellenwerts und insbesondere im Hinblick auf ein Überschreiten des Beschleunigungsschwellenwerts überwacht wird.
3. c) Der Gradient der Drehzahl des Antriebsrads 9 überschreitet einen vorgegebenen Antriebsraddrehzahlgradientenschwellenwert und das Übersetzungsverhältnis ist ungleich Null, d. h. es besteht eine Kopplung zwischen dem Antriebsmotor 2 und dem Antriebsrad 9.
4. d) Das Motormoment des Antriebsmotors 2 ist größer als ein vorgegebener Momentenschwellenwert und das Übersetzungsverhältnis ist ungleich Null. Bei Hybridfahrzeugen, kann das Antriebsmoment dabei je nach Hybridkonzept dem Gesamtantriebsmoment aller Antriebsmotoren oder nur eines Teils der Antriebsmotoren entsprechen.

The first condition is met if, according to a speed monitoring of the speed of the drive motor, one or more of the following conditions are fulfilled:

1. a) The speed of the drive motor 2nd is higher than a predetermined speed threshold, the drive train is not open, ie the clutch 3rd or a torque converter causes at least a slippage of power transmission between the drive motor 2nd and the drive wheel 9 , and the gradient of the speed of the drive motor 2nd is greater than a predetermined speed gradient threshold.
2. b) The product of the speed of the drive motor 2nd and the gear ratio of a transmission 3rd in the drive train is greater than a predetermined drive wheel speed threshold value and the time derivative of the product from the speed of the drive motor 2nd and the gear ratio exceeds a predetermined speed gradient threshold. Here, a time-variable variable can also be recorded and made available for the transmission ratio, so that a slip of a clutch can also be taken into account. In particular, the time derivation of the product from the speed of the drive motor 2nd and the gear ratio in an acceleration of the motor vehicle 1 are converted, which is then monitored with respect to an acceleration threshold value and in particular with a view to exceeding the acceleration threshold value.
3. c) The gradient of the speed of the drive wheel 9 exceeds a predetermined drive wheel speed gradient threshold and the gear ratio is not zero, ie there is a coupling between the drive motor 2nd and the drive wheel 9 .
4. d) The engine torque of the drive motor 2nd is greater than a predetermined torque threshold and the gear ratio is not equal to zero. In the case of hybrid vehicles, depending on the hybrid concept, the drive torque can correspond to the total drive torque of all drive motors or only a part of the drive motors.

If one or more of the above conditions a) - d) are met (alternative: yes), then the first condition is met and the process is carried out with step S4 continued. Otherwise (alternative: no) no error is recognized and the procedure with step S1 started again.

wobei P_AG1 , P_AG2, ..., P_AGn die von dem entsprechenden n-ten Antriebsmotor bereitgestellte mechanische Leistung und ü_AG1 , ü_AG2 ... , ü_AGn den entsprechenden Kopplungszuständen für eine Kopplung des betreffenden n-ten Antriebsmotors mit dem Triebstrang entsprechen.Alternatively, the check as to whether the first condition is fulfilled can also be carried out using performance monitoring. In the case of a power-based monitoring method, the first condition is recognized as being fulfilled if the instantaneous total mechanical power P _{Kfz of} the motor vehicle exceeds a predetermined maximum permissible power threshold value Pmax and the clutch 23 closed is. The power of the motor vehicle P _Kfz results from the sum of the powers of the drive motors available in a hybrid drive system in the motor vehicle 21st , 22 . Depending on whether a corresponding operating mode can occur, drive units uncoupled from the drive train at the current operating point can be disregarded via their coupling status (ü = 0 if uncoupled) and removed from the total: $${\text{P}}_{\text{Motor vehicle}}={\text{P}}_{\text{AG1}}*{\text{ü}}_{\text{AG1}}+{\text{P}}_{\text{AG2}}*{\text{ü}}_{\text{AG}\mathrm{2nd}}+...+{\text{P}}_{\text{AGn}}*{\text{ü}}_{\text{AGn}}$$

where P _AG1 , P _AG2 , ..., P _AGn the mechanical power provided by the corresponding nth drive motor and ü _AG1 , ü _AG2 ..., ü _AGn the corresponding coupling _states for coupling the relevant nth drive motor to the Drive train correspond.

wobei J_VM dem Trägheitsmoment des Verbrennungsmotors, M_EM dem Drehmoment des Elektroantriebs, ω der Winkelgeschwindigkeit des gemeinsamen Triebstrangs und die dω/dt der Winkelbeschleunigung des Triebstrangs entsprechen.For example, this sum is for a vehicle with a first drive motor 21st as an internal combustion engine and an electric drive as a second drive motor 23 shown as drive units on a common drive train in the coupled state as follows: $${\text{P}}_{\text{Motor vehicle}}=\left({\text{J}}_{\text{VM}}*\text{d}\mathrm{\omega }/\text{German}*\mathrm{\omega }+{\text{M}}_{\text{EM}}*\mathrm{\omega }\right)*\text{ü}$$

where J _VM corresponds to the moment of inertia of the internal combustion engine, M _{EM to} the torque of the electric drive, ω to the angular velocity of the common drive train and the dω / dt to the angular acceleration of the drive train.

In addition, it would be possible to use the energy E of the drive motors 21st , 22 evaluate according to the same principle and specify an energy threshold for monitoring the drive energies. This is possible because the time derivative of the energy dE / dt corresponds to the power and is therefore equivalent to it.

For special operating conditions, which are characterized by a higher power consumption in normal operation, such as start / cold start of an internal combustion engine, mechanisms can be implemented which apply an additional power offset P _{offset to} the maximum permissible power threshold value Pmax for a certain period of time and thereby Increase system robustness.

Will in step S3 If the total mechanical power P _{Kfz of} the motor vehicle is determined to exceed the maximum permissible power threshold value Pmax (alternative: yes), the first condition is met and the method is carried out with step S4 continued. Otherwise (alternative: no) no error is recognized and the process returns to step S1 started again.

In step S3 an energy-based monitoring method can alternatively be carried out. In the case of the energy-based monitoring method, a fault is determined when the instantaneous total mechanical energy content E _{motor vehicle of} the motor vehicle exceeds a predetermined maximum permissible energy threshold Emax and the clutch 23 closed is. The total mechanical energy content E _{Kfz of} the motor vehicle results 1 from the sum of the energy _contents E _AG1 , E _AG2 , ..., E _{AGn of those} in the motor vehicle 1 available drive motors 21st , 22 . Depending on whether a corresponding operating mode can occur, drive units uncoupled from the drive train at the current operating point can be disregarded via their coupling status (ü = 0 if uncoupled) and removed from the total: $${\text{E}}_{\text{Motor vehicle}}={\text{E}}_{\text{AG1}}*{\text{ü}}_{\text{AG1}}+{\text{E}}_{\text{AG2}}*{\text{ü}}_{\text{AG}\mathrm{2nd}}+...+{\text{E}}_{\text{AGn}}*{\text{ü}}_{\text{AGn}}$$

In step S4 the second condition is checked whether the motor vehicle 1 experiences an unjustified physical vehicle jerk. The vehicle jerk corresponds to a change in an acceleration of the motor vehicle 1 , especially a positive change in acceleration. For this purpose, a permissible jerk acceleration a _{PTD is} dependent on a driver and driver assistance system request or brake actuation based on the actuations of the accelerator pedal 5 or the brake pedal 6 certainly.

The acceleration of the vehicle _jerk a _{jerk is also} determined. For this purpose, acceleration _information a _{veh of} the motor vehicle 1 , in particular from an initial acceleration sensor and / or by evaluating a change in a wheel speed and / or radar and / or camera-based detections. As a rule, the acceleration _information a _{veh stands} for other functions in the motor vehicle 1 to disposal.

The vehicle _jerk da _veh / dt can be determined by deriving and, if necessary, filtering (smoothing) the acceleration _information a _veh .

The vehicle jerk is then integrated again into an acceleration variable in order to remove offsets of the acceleration information. This gives a pure vehicle acceleration, which indicates the acceleration of the motor vehicle over the road. The offsets of the acceleration information can e.g. B. occur due to an incline of the road in a system with an inertial acceleration sensor. The acceleration value a _Jerk determined in this way by the integration corresponds to the additional acceleration brought about by the initial vehicle _{jerk in} relation to the stationary state present before the vehicle _jerk . The integration is particularly necessary when using initial acceleration sensors, since these can output an acceleration offset due to a road inclination and gravity. If other methods are used, the integration step may be omitted.

A vehicle jerk is recognized when the acceleration increase due to the vehicle _jerk exceeds the predetermined permissible acceleration a _PTD . If an unjustified vehicle jerk is recognized (alternative: yes), then in step S5 an error reaction is executed, otherwise the process moves to step S1 jumped back and no error situation detected.

As an error reaction, for example, in step S5 an injection of fuel is prevented or the function of the engine control unit 4th be deactivated.

Alternatively, interventions in the power transmission are conceivable. In general, the required error response should reduce the performance of the drive unit concerned or prevent its power transmission. Possible error responses when unwanted acceleration is detected are known substitute responses in the engine control unit 4th that prevent injection or completely reset the control unit software. As an alternative, interventions in the power transmission, such as a neutral gear request to the transmission control unit and / or a braking force request to the brake system or to an existing electric drive, are conceivable.

If one of the drive motors to be deactivated is an electric drive, in the event of a fault, a neutral torque can be switched to an active short circuit via the phase strands of the electrical machine or braking torque can be requested.

If the above performance condition is not met (alternative: no), the process returns to step by step S1 with the steps S1 to S4 repeated cyclically.

QUOTES INCLUDE IN THE DESCRIPTION

This list of documents listed by the applicant has been generated automatically and is only included for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 102013107781 A1 [0005]
• DE 102014206491 A1 [0008]

Claims (13)

Method for monitoring a motor vehicle (1) with a drive system (2), with the following steps: Checking (S3) a first condition which depends on a speed of the drive system (2) and / or a speed gradient of the drive system, - checking (S4) a second condition which depends on a measure of a vehicle jerk; - triggering (S5) an error reaction which indicates an impending unwanted acceleration of the motor vehicle (1) when the motor vehicle (1) is in a stop state and the first and second conditions are met. Procedure according to Claim 1 The first condition comprises checking a speed of the drive system (2) with respect to a predetermined speed threshold and / or checking a speed gradient of the drive system (2) with respect to a predetermined speed gradient threshold. Procedure according to Claim 1 or 2nd , the first condition of checking a power of the drive system (2), which is based on a power balance of the instantaneous mechanical powers of one or more coupled drive motors (21, 22) of the drive system (2), with regard to a power threshold and / or checking an energy of the drive system (2), which is based on an energy balance of the currently provided energies of all coupled drive motors (21, 22), with respect to an energy threshold. Procedure according to one of the Claims 1 to 3rd The method is only carried out when the motor vehicle (1) is in a stop state, the stop state being assumed when the speed of the motor vehicle (1) is below a predetermined speed threshold value. Procedure according to Claim 4 , wherein the holding state is assumed when there is a torque request that is smaller than a predetermined torque request threshold. Procedure according to one of the Claims 1 to 5 , the measure of the vehicle jerk indicating a change in the vehicle acceleration or a vehicle acceleration determined from the change in the vehicle acceleration with respect to the road. Procedure according to one of the Claims 1 to 6 wherein the second condition includes checking the amount of vehicle jerk with respect to a predetermined acceleration threshold. Procedure according to Claim 7 , wherein acceleration information is derived and then integrated in order to obtain vehicle acceleration with respect to the road. Device for monitoring a motor vehicle (1) with a drive system (2), the device being designed to: to check a first condition which depends on a speed of the drive system (2) and / or a speed gradient of the drive system, - to check a second condition which depends on a measure of a vehicle jerk; - trigger an error reaction which indicates an impending unwanted acceleration of the motor vehicle (1) when the motor vehicle (1) is in a stop state and the first and second conditions are met. Motor vehicle with a drive system and the device according to Claim 9 . Computer program which is set up to carry out all steps of a method according to one of the Claims 1 to 8th to execute. Electronic storage medium on which a computer program is based Claim 11 is saved. Electronic control device, which is an electronic storage medium Claim 12 having.

Images