An SI Engine Load Torque Observer Based on Combined Input and Parameter Estimation

Engine load torque estimators are sensitive to errors in engine torque reconstruction. In order to increase the estimation accuracy, a combined estimator of load torque and engine torque parameters is proposed in this paper. The combined estimator is based on a set-membership method, and known load torque and parameter bounds. The emphasis is on analysis of estimation error and related practical guidelines for improved performance. The estimator is verified by experiment.