CONTROLLER FOR INTERNAL-COMBUSTION ENGINE

摘要

A controller for an internal-combustion engine that determines a target suction pipe pressure with better accuracy. The controller for determining the target suction pipe pressure is provided in the internal-combustion engine that has a variable valve mechanism for adjusting a lift amount of a suction valve to ensure a first operating region for achieving a target suction air amount by changing the target suction pipe pressure while keeping a target lift amount contact. The controller determines the target lift amount (ALCMD_PA) in the first operating region in accordance with the reference suction air amount (GALTHCMD) determined according to an operating state of the internal-combustion engine. The target suction pipe pressure (PBGACMD) in the first operating region is represented by a primary expression for the target suction air amount (GAIRCMD), and a gradient (A) and an intercept (B) of the primary expression are calculated in on the basis of the target lift amount, thereby the primary expression being obtained. The target suction pipe pressure (PBGACMD) in the first operating region is calculated by substituting the target suction air amount for the obtained primary expression.