| 摘要 |
PROBLEM TO BE SOLVED: To accurately judge an occurring state of knocking by suppressing influence of a noise component. SOLUTION: An engine ECU executes a program including a step of calculating a correlation coefficient K based on a result of comparing a vibration waveform of an engine and a prestored knock waveform model, a step (S200) of calculating an intensity value LOG(V) from intensity V detected according to a signal transmitted from a knock sensor, a step (S204) of forming a frequency distribution of the intensity values LOG(V) by using the intensity value LOG(V) in an ignition cycle wherein the correlation coefficient K larger than a threshold value K(1) is calculated, and a step (S206) of counting a knock occupancy rate KC by using the frequency distribution drawn. When a waveform of vibration of the noise component is included in the vibration waveform, the correlation coefficient K is calculated to be smaller than the case where the waveform of vibration of the noise component is not included. COPYRIGHT: (C)2007,JPO&INPIT
|
