Patent ID: 8335628
Filing Date: 2012-12-18
Classification: F01L,F02D,Y02T

Abstract:
1. A method for controlling a variable valve apparatus of an internal combustion engine, comprising: (a) setting a target cam phase corresponding to a current operation state of the engine received from a vehicle controller via a controller area network (CAN) bus; (b) determining whether a deviation of a current cam phase from the target cam phase is greater than a predetermined deviation; (c) calculating a proportion-integral-derivation (PID) sliding surface based on the target cam phase in a case when the deviation is greater than the predetermined deviation; (d) calculating a control current for controlling a cam phase to move on the PID sliding surface; and (e) operating the variable valve apparatus so that a current cam phase can follow the target cam phase by converting the calculated control current to a driving duty ratio; wherein a final control current is obtained by applying a current compensation value according to engine oil temperature and a non-linear output calculated in the PID sliding surface to the control current calculated in the step (d).