Internal combustion engine knock determination device, knock determination method, program for realizing the method, and recording medium storing the program

摘要

An engine ECU executes a program that includes the steps of: calculating 15-degrees integrated value integrating vibration intensity for each of six crank angle ranges (S110); detecting an amount of change in the 15-degrees integrated value between ignition cycles (S112); specifying two ranges having larger amounts of change (S114); 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 (S116); calculating a coefficient of correlation K corresponding to a difference between a vibration waveform and a knock waveform model (S122) 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) (YES at S126), determining that knock has occurred (S128).