Patent ID: 6553958
Filing Date: 2003-04-29
Classification: F02B,F02D,Y02T

Abstract:
A method for controlling a multi-cylinder internal combustion engine, the method comprising:determining a first engine operating variable using a model having at least one adjustable model parameter; wherein the step of determining a first engine operating variable comprises: estimating engine torque for current operating conditions; estimating load torque for current operating conditions; and determining an estimated engine speed based on the estimated engine torque and estimated load torque; measuring a second engine operating variable using an associated sensor; modifying at least one adjustable model parameter based on a relationship between the first and second engine operating variables to adapt the model for variations in engine operation; comparing the estimated engine speed to an actual engine speed determined using an engine speed sensor; and wherein the step of modifying the at least one adjustable model parameter includes modifying the model parameter based on a difference between the estimated and actual engine speeds, wherein the step of modifying is performed only if the difference between the estimated and actual engine speeds exceeds a corresponding threshold.