Method for the robust identification of knocking in an internal combustion engine, control device, and motor vehicle
AssigneeBayerische Motoren Werke Aktiengesellschaft
InventorRene Weiss
Life of this patent
Estimating the term…
Abstract
A method and control device for automatically identifying knocking in an internal combustion engine, wherein, in a predefined measurement time frame, a signal of the knocking sensor is received and evaluated with respect to a criterion for detecting knocking. A basic threshold value predefined for the identification of knocking is modified by a predefined variable interference factor, which depends on a relative point in time at which an inlet valve of at least one of the cylinders closes in relation to a predefined reference point. A signal based on the sensor signal is only identified as knocking if it reaches at least the modified basic threshold value.
Claims17
A method for automatic knocking identification in an internal combustion engine with a plurality of cylinders, a variable inlet valve stroke, and a knocking sensor, the method comprising:
- operating the internal combustion engine with an inlet valve closure before an end of an induction cycle;
- acquiring a sensor signal representing an acoustic signal or a physical vibration signal in a predetermined measurement time window by the knocking sensor;
- evaluating the sensor signal with regard to a predetermined criterion for detecting knocking, the evaluating further comprising determining that a signal based on the sensor signal reaches at least a predetermined basic threshold value to be identified as knocking;
- modifying the basic threshold value to create a modified basic threshold value using a predetermined variable interference factor that is dependent on a relative time of a closure of an inlet valve of at least one of the plurality of cylinders relative to a predetermined reference point;
- identifying the signal as knocking only if it at least reaches the modified basic threshold value;
- and
- adjusting inlet valves or a variable valve train in response to identifying the signal as knocking in order to avoid or reduce the knocking.
A control device for an internal combustion engine for automatic detection of knocking, comprising:
- an input interface for acquiring a sensor signal of a knocking sensor, wherein the sensor signal represents an acoustic signal or a physical vibration signal;
- a data memory;
- an output interface for outputting a detection signal indicating a detection of knocking;
- and
- at least one processor device configured to:
- receive the sensor signal from the input interface in a predetermined measurement time window;
- evaluate the sensor signal with regard to a predetermined criterion for detecting knocking at least by determining that a signal based on the sensor signal reaches at least a predetermined basic threshold value to be identified as knocking;
- modify the basic threshold value to create a modified basic threshold value using a predetermined variable interference factor that is dependent on a relative time of a closure of an inlet valve of at least one of a plurality of cylinders relative to a predetermined reference point, wherein the closure of an inlet valve occurs before an end of an induction cycle;
- identify the signal as knocking only if it at least reaches the modified basic threshold value;
- and
- adjust inlet valves or a variable valve train in response to identifying the signal as knocking in order to avoid or reduce the knocking.
Dependencies are inferred from the claim text.