Method and device for emission monitoring of a combustion engine in a motor vehicle

1. A method for monitoring pollutant emissions during operation of at least one of a combustion engine and an exhaust-after-treatment device in a motor vehicle, the method comprising:

for each of at least one pollutant category:

based on at least one operating-state variable of the motor vehicle, determining a respective pollutant-limit value using a provided emission limit-value model, the at least one operating-state variable including at least one of (a) vehicle velocity, (b) ambient-air pressure, and (c) engine temperature, wherein the determining of the respective pollutant-limit value includes the provided emission limit-value model receiving as input the at least one operating-state variable and calculating the respective pollutant-limit value using the input at least one operating-state variable;

ascertaining a respective pollutant-concentration variable using a sensor; and

determining occurrence of an error in response to detecting that the ascertained respective pollutant-concentration variable exceeds the respective pollutant-limit value,

wherein the at least one operating-state variable includes the ambient-air pressure.

2. The method of claim 1 , wherein the pollutant-limit value varies according to a distance traveled.

3. The method of claim 2 , wherein a value of the respective pollutant-concentration variable varies based on the distance traveled.

4. The method of claim 3 , wherein a value of the respective pollutant-concentration variable is determined by integrating base values of the respective pollutant-concentration variable across a period of time required by the motor vehicle to travel a predefined driving distance.

5. The method of claim 1 , wherein the respective pollutant-limit value includes at least one gradient-limit value, and the error is determined if an absolute value of a gradient of the respective pollutant-concentration variable exceeds the respective gradient-limit value.

6. The method of claim 5 , wherein the at least one gradient-limit value is fixedly predefined.

7. The method of claim 5 , wherein the at least one gradient-limit value is predefined as a function of the at least one operating-state variables of the motor vehicle.

8. The method of claim 1 , further comprising, responsive to the determination of the occurrence of the error:

generating an error signal; and

storing the generated error signal together with associated operating-state variables.

9. The method of claim 1 , further comprising, responsive to the determination of the occurrence of the error:

generating an error signal; and

outputting a signal representing the generated error signal.

10. The method as recited in claim 1 , wherein the at least one operating-state variable includes the vehicle velocity.

11. The method as recited in claim 1 , wherein the at least one operating-state variable includes the engine temperature.

12. The method as recited in claim 1 , wherein the at least one operating-state variable includes the vehicle velocity, the ambient-air pressure, and the engine temperature.

13. A control unit for monitoring pollutant emissions during operation of at least one of a combustion engine and an exhaust-after-treatment device in a motor vehicle, the control unit comprising:

a processor; and

at least one interface;

wherein the processor is configured to, for each of at least one pollutant category:

based on at least one operating-state variable of the motor vehicle obtained via the at least one interface, determine a respective pollutant-limit value using an emission limit-value model, the at least one operating-state variable including at least one of (a) vehicle velocity, (b) ambient-air pressure, and (c) engine temperature, wherein for the determination of the respective pollutant-limit value, the provided emission limit-value model is configured to receive as input the at least one operating-state variable and calculate the respective pollutant-limit value using the input at least one operating-state variable;

ascertain a respective pollutant-concentration variable based on output of a sensor received via the at least one interface; and

determine occurrence of an error in response to detecting that the ascertained respective pollutant-concentration variable exceeds the respective pollutant-limit value;

wherein the at least one operating-state variable includes the ambient-air pressure.

14. A non-transitory computer-readable medium on which are stored instructions that are executable by a processor and that, when executed by the processor, cause the processor to perform a method for monitoring pollutant emissions during operation of at least one of a combustion engine and an exhaust-after-treatment device in a motor vehicle, the method comprising:

for each of at least one pollutant category:

based on at least one operating-state variable of the motor vehicle, determining a respective pollutant-limit value using a provided emission limit-value model, the at least one operating-state variable including at least one of (a) vehicle velocity, (b) ambient-air pressure, and (c) engine temperature, wherein the determining of the respective pollutant-limit value includes the provided emission limit-value model receiving as input the at least one operating-state variable and calculating the respective pollutant-limit value using the input at least one operating-state variable;

ascertaining a respective pollutant-concentration variable using a sensor; and

determining occurrence of an error in response to detecting that the ascertained respective pollutant-concentration variable exceeds the respective pollutant-limit value;

wherein the at least one operating-state variable includes the ambient-air pressure.