Partially premixed combustion multi-cylinder engine cycle-to-cycle-oriented temperature estimation and control

Advanced combustion concepts like partially premixed combustion (PPC) are sensitive to inlet gas conditions especially inlet temperature. To estimate the combustion parameters like ignition delay on a cycle-to-cycle basis, both complementary filter and extended Kalman filter were designed to estimate the inlet temperature, and the ignition delay was calculated with properly estimated temperature. A two valve fast thermal management system was used to control the inlet temperature, and a PI controller with the lambda tuning method was used. The estimation and control algorithm were verified on a six-cylinder heavy duty engine.