摘要:
A band pass filter processing extracts the vibration component (frequency component) of the 1st to the 4th order frequency band from the output of the knock sensor. A primary frequency band is established as the frequency band containing the fundamental frequency (primary resonance frequency) which is the lowest frequency of the knocking vibration frequencies. The 2nd to the 4th order frequency band is established as the frequency band containing the 2nd to the 4th order resonance frequency. Based on the vibration strength of the primary frequency component, the comparison result between the composite vibration waveform which compounded the 1st to the 4th order frequency component and the ideal knock waveform, and the vibration strength of the summation of the 1st to the 4th order frequency component, the noise and knocking are distinguished from each other with sufficient accuracy.
摘要:
Based on results of a knock control for adjusting ignition timing in accordance with the occurrence of knocking, an electronic control unit computes deposit required ignition timing akgrg, which is ignition timing determined by taking adhesion of deposits in an internal combustion engine into consideration. Based on the deposit required ignition timing akgrg, the electronic control unit reduces a vvt allowable variable range of a target VVT advancement amount, which is a control target value of a variable valve timing mechanism. The electronic control unit corrects a required ignition timing based on the actual VVT advancement amount vt, which is chanted according to the reduction of the allowable variable range of the target VVT advancement amount. As a result, problems resulting from the adhesion of deposits are effectively avoided.
摘要:
An engine ECU executes a program including the steps of: calculating a coefficient of correlation K in accordance with a result of comparing a waveform of a vibration of a frequency band including a resonance frequency of an engine with a knock waveform model previously created as a waveform of a vibration caused when the engine knocks; calculating a knock intensity N from an intensity of a vibration of a frequency band excluding the resonance frequency of the engine; if knock intensity N is larger than a reference value and coefficient of correlation K is larger than a threshold value, determining that the engine knocks; and if knock intensity N is smaller than the reference value and/or coefficient of correlation K is smaller than the threshold value, determining that the engine does not knock.
摘要:
A knocking judgement method for an internal combustion engine, in which an engine ECU executes a program judging whether or not such ones of integrated values calculated by integrating the output of a knock sensor at every five degrees of a crank angle are larger than a tentative knock judgement value, in vibrations of a fourth frequency band containing the resonance frequency of the engine, tentatively judging that a knocking has occurred, in case the integrated value larger than the tentative knock judgement value is a predetermined number or more, and judging that no knocking has occurred, in case the integrated value larger than the tentative knock judgement value is not more than the predetermined number.
摘要:
An engine ECU executes a program including the steps of: determining that the condition that there is a possibility of occurrence of knocking is satisfied, based on the result of comparison between a vibration waveform of an engine and a knock waveform model; calculating a 40CA integrated value by integrating magnitudes of vibration occurring in the engine for a range of crank angle of 40°; calculating a knock magnitude N by dividing the 40CA integrated value by a BGL; determining that knocking has occurred when the knock magnitude N is larger than a determination value V(KX); and determining that knocking has not occurred when the knock magnitude N is smaller than the determination value V(KX).
摘要:
An engine ECU executes a program including a step of setting a search range of the crank angle of a peak value P that is the largest integrated value in a vibration waveform of an engine detected by calculating integrated values that are integrals of output voltage values of a knock sensor for every five degrees of a crank angle such that the search range may include the crank angle increasing with increase in engine speed NE, and a step of detecting the crank angle of the largest integrated value in the search range, and setting the detected crank angle as the crank angle of peak value P in the vibration waveform. At the crank angle based on the crank angle of peak value P, the vibration waveform is compared with a knock waveform model.
摘要:
An engine ECU executes a program including the steps of: calculating a coefficient of correlation K in accordance with a result of comparing a waveform of a vibration of a frequency band including a resonance frequency of an engine with a knock waveform model previously created as a waveform of a vibration caused when the engine knocks (S112); calculating a knock intensity N from an intensity of a vibration of a frequency band excluding the resonance frequency of the engine (S114); if knock intensity N is larger than a reference value and coefficient of correlation K is larger than a threshold value (YES at S116), determining that the engine knocks (S118); and if knock intensity N is smaller than the reference value and/or coefficient of correlation K is smaller than the threshold value, determining that the engine does not knock (S122).
摘要:
Out of synthesized waveforms of vibrations in a first frequency band A to a third frequency band C, a knock magnitude N is calculated by using a portion β having an integrated value greater than a reference magnitude in a knock region but not using a portion having an integrated value greater than the reference magnitude out of the knock region (i.e., a region obtained by excluding the knock region from a knock detecting gate). In a case where knock magnitude N is greater than a determination value V(KX), it is determined that knocking occurs. In contrast, in a case where knock magnitude N is not greater than determination value V(KX), it is determined that no knocking occurs.
摘要:
An engine ECU executes a program including the steps of: calculating a magnitude value LOG(V) by logarithmically converting a magnitude V of vibration occurring in an engine, calculating a median V(50) and a standard deviation σ of magnitude values LOG(V); and setting, to the product of the standard deviation σ and a factor A, a first upper limit of a determination value V(KX) that is to be compared with a knock magnitude N for determining whether or not knocking has occurred, and setting a first lower limit of the determination value V(KX) to the product of the standard deviation σ and a factor B.
摘要:
A controller for an engine including a fuel vapor processing mechanism. The controller determines the amount of fuel vapor drawn into an intake passage based on the concentration of fuel vapor purged into the purge passage. The controller corrects the fuel injection amount of a fuel injection valve in accordance with the determined amount of fuel vapor. The controller starts correcting the fuel injection amount from the cylinder that is undergoing an intake stroke when the crankshaft is rotated to a certain crank angle.