摘要:
An output signal of a knock sensor is filtered with a plurality of band-pass filters to extract vibration waveform components of a plurality of frequency bands (f1-f4). Weighting coefficients (G1-G4) which multiply the vibration waveform component of each frequency band are established in such a manner as to be a small value as a noise intensity of each frequency band becomes larger. Thereby, the vibration waveform component of a plurality of frequency bands is synthesized by weighting according to an influence of a noise intensity of each frequency band. Even when the noise is superimposed on the vibration waveform component of any of the frequency bands, it becomes possible to reduce the influence of the noise and to synthesize the vibration waveform component of each frequency band, and an accurate knock determination can be performed based on the composite vibration waveform.
摘要:
A 90° integrated value calculating unit of an engine ECU calculates a 90° integrated value obtained by integrating a magnitude. A calculating unit calculates a knock magnitude by dividing 90° integrated value by a BGL. A value obtained by subtracting a standard deviation σ from a median value of 90° integrated value is determined as the BGL. An ignition timing control unit controls the ignition timing depending on whether knock magnitude is equal to or larger than a determination value. A median value calculating unit calculates median value of 90° integrated value. A standard deviation calculating unit calculates standard deviation of 90° integrated value. A first stop unit stops updating of median value and standard deviation when 90° integrated value is smaller than a first threshold value or is equal to or larger than a second threshold value.
摘要:
An output signal of a knock sensor is filtered with a plurality of band-pass filters to extract vibration waveform components of a plurality of frequency bands (f1-f4). Weighting coefficients (G1-G4) which multiply the vibration waveform component of each frequency band are established in such a manner as to be a small value as a noise intensity of each frequency band becomes larger. Thereby, the vibration waveform component of a plurality of frequency bands is synthesized by weighting according to an influence of a noise intensity of each frequency band. Even when the noise is superimposed on the vibration waveform component of any of the frequency bands, it becomes possible to reduce the influence of the noise and to synthesize the vibration waveform component of each frequency band, and an accurate knock determination can be performed based on the composite vibration waveform.
摘要:
A 90° integrated value calculating unit of an engine ECU calculates a 90° integrated value obtained by integrating a magnitude. A calculating unit calculates a knock magnitude by dividing 90° integrated value by a BGL. A value obtained by subtracting a standard deviation σ from a median value of 90° integrated value is determined as the BGL. An ignition timing control unit controls the ignition timing depending on whether knock magnitude is equal to or larger than a determination value. A median value calculating unit calculates median value of 90° integrated value. A standard deviation calculating unit calculates standard deviation of 90° integrated value. A first stop unit stops updating of median value and standard deviation when 90° integrated value is smaller than a first threshold value or is equal to or larger than a second threshold value.
摘要:
An engine ECU executes a program including the steps of: calculating a knock magnitude N by dividing an integrated value lpkknk obtained by integrating the magnitude of vibration in the knock detection gate by BGL; controlling ignition timing according to a result of comparison between knock magnitude N and a determination value VJ; stopping updating of a standard deviation σ when it is determined that determination value VJ to be compared with knock magnitude N is to be changed; updating a median value VM by increasing an update amount of median value VM; and updating BGL according to median value VM and standard deviation σ.
摘要:
An engine ECU executes a program including the steps of: calculating a knock magnitude N by dividing an integrated value lpkknk obtained by integrating the magnitude of vibration in the knock detection gate by BGL; controlling ignition timing according to a result of comparison between knock magnitude N and a determination value VJ; stopping updating of a standard deviation σ when it is determined that determination value VJ to be compared with knock magnitude N is to be changed; updating a median value VM by increasing an update amount of median value VM; and updating BGL according to median value VM and standard deviation σ.
摘要:
An engine ECU executes: calculating 15-degrees integrated value integrating vibration intensity for each of six crank angle ranges; detecting an amount of change in the 15-degrees integrated value between ignition cycles; specifying two ranges having larger amounts of change; specifying a crank angle having intensity larger than that of a neighboring crank angle in a search range determined to be the same as the specified ranges; calculating a coefficient of correlation K corresponding to a difference between a vibration waveform and a knock waveform model while the specified crank angle is matched with a timing at which intensity peaks in the knock waveform model; and, if the coefficient of correlation K is larger than a threshold value K(0), determining that knock has occurred.
摘要:
An engine ECU executes: calculating 15-degrees integrated value integrating vibration intensity for each of six crank angle ranges; detecting an amount of change in the 15-degrees integrated value between ignition cycles; specifying two ranges having larger amounts of change; specifying a crank angle having intensity larger than that of a neighboring crank angle in a search range determined to be the same as the specified ranges; calculating a coefficient of correlation K corresponding to a difference between a vibration waveform and a knock waveform model while the specified crank angle is matched with a timing at which intensity peaks in the knock waveform model; and, if the coefficient of correlation K is larger than a threshold value K(0), determining that knock has occurred.
摘要:
An engine ECU executes a program including: the step (S222) of increasing a determination value V(J) by a correction amount A(3) if the number of knock intensities N not lower than the determination value V(J) is not smaller than a threshold value B(1) (YES at S220) among knock intensities N of a plurality of predetermined number of continuous ignition cycles; and the step (S232) of increasing the determination value V(J) by a correction amount A(5) if the number of knock intensities N not smaller than the determination value V(J) is not smaller than a threshold value B(3) (YES at S230), among knock intensities N of a plurality of ignition cycles satisfying the condition that a coefficient of correlation K calculated by comparing a vibration waveform and a knock waveform model is not smaller than a threshold value K(1), of the knock intensities of a plurality of predetermined continuous ignition cycles.
摘要:
An engine ECU executes operations including: extracting vibration intensities of a plurality of frequency bands from vibration detected by a knock sensor, multiplying the extracted vibration intensity of each frequency band by a weight coefficient and adding the results in correspondence with crank angles to calculate integrated values of every five degrees; calculating a coefficient of correlation based on a result of comparison between a vibration waveform of a frequency band and a knock waveform model prepared in advance; calculating a knock intensity; determining occurrence of knocking in accordance with the calculated coefficient of correlation and the knock intensity; and determining no occurrence of knocking in accordance with the calculated coefficient of correlation and the knock intensity.