Control apparatus and control method for variable valve mechanism

摘要

In a control apparatus for a variable valve mechanism that varies a valve characteristic of an engine valve, in a saturated state in which a calculated manipulated variable of the variable valve mechanism exceeds an outputtable manipulated variable, convergence to a desired position is achieved while suppressing a response delay and an overshoot. If a feedforward manipulated variable calculated according to a reference response exceeds an outputtable limit manipulated variable, a saturating amount (feedforward manipulated variable—limit manipulated variable) is integrated. Upon completion of the integration, the feedforward manipulated variable is corrected based on an FF manipulated variable correction amount, and the integrated value of saturating amount is replaced by a value obtained by subtracting the FF manipulated variable correction amount each time a correction is made. When the integrated value of saturating amount reduces to a predetermined value or less, a control mode is switched to feedback control.

主权项

1. A control apparatus for a variable valve mechanism that varies a valve characteristic of an engine valve, comprising:
a feedforward manipulated variable calculating unit that calculates a feedforward manipulated variable according to a dynamic characteristic of the variable valve mechanism; an actual manipulated variable calculating unit that calculates an actual manipulated variable that can be output by the variable valve mechanism; a corrective manipulated variable calculating unit that calculates a corrective manipulated variable for correcting a difference between the calculated feedforward manipulated variable and the actual manipulated variable while changing the valve characteristic of the engine valve by controlling the variable valve mechanism; and a feedforward manipulated variable correcting unit that corrects the feedforward manipulated variable according to the corrective manipulated variable after the corrective manipulated variable is calculated; wherein the corrective manipulated variable calculating unit calculates, as the corrective manipulated variable, an integrated value of saturating amount obtained from the actual and feedforward manipulated variables when the feedforward manipulated variable differs in a particular way from the actual manipulated variable.