A Fourier Analysis Based Synthetic Method for In-cylinder Pressure Estimation

The cylinder pressure signal, as an instantaneous and direct measure of the engine operation, contains valuable information for closed loop engine control and offers very useful engine monitoring and control capabilities.

The estimation technique for cylinder pressure has been investigated for many years. Based on the Frequency Analysis Method, a synthetic estimation method is proposed in this paper to estimate pressure. Methods that are successful in obtaining a more accurate estimated cylinder pressure over a wider range of crankshaft angle are reported. Quantitative results obtained from application of the method are also given.