Abstract
Exhaust emissions and combustion stability of diesel engines can be improved by feedback control using a cylinder pressure sensor (CPS). However output of the CPS can deteriorate due to deposits on the sensor. To address this issue, an on-board model was developed to compensate CPS output based on the spring-mass-damper model. Young's modulus of the deposit causes a variation of the spring constant and resulting degradation of the signal level. Deposit porosity leads to a variation of the damper constant and resulting signal delay. The proposed model based on the analysis can estimate the cylinder pressure with the required accuracy for the feedback control.
