An investigation on the relationship between engine knock and amplitude characteristics of spark plug's ionic current signals

This paper investigated application of ionic current signals in engine's knock detection. At the same engine operating condition (same engine speed and torque), the wave shape and amplitude characteristics acquired under the different knock intensity were compared between the signals of cylinder pressure and ionic current. And then further detective the relationship between time-domain integral of ionic current signals and knock intensity. The result proves that the serious engine knock can be accurately determined by using ionic current signals amplitude's integral. This technique may be one of the calibration methods for gasoline engine knock.