| 摘要 |
PURPOSE:To prevent over-rotation of a primary turbo supercharger by correcting a single-twin switching judgement line for judging switching from a single turbo condition to a twin turbo condition in response to the atmospheric pressure. CONSTITUTION:A single-twin switching judgement basic value TP2B for an engine load TP in the standard atmospheric pressure is set based on engine rotational speed N (step S2), and a single twin atmospheric pressure corrective coefficient KTWNALT which is smaller as the atmospheric pressure is lower is set based on the atmospheric pressure ALT (step S3). A single-twin switching judgement basic value TP2B is corrected by the single-twin atmospheric pressure corrective coefficient, and the single twin switching judgement value TP2 is set (step S4). When it is judged that the engine load TP is larger than the single-twin switching judgement value TP2 (step S5), the target of control is transferred to switching of the single turbo condition to the twin turbo condition. Consequently, full opening starting timing of the exhaust control valve of a secondary turbo supercharger is quickened following a decrease in the atmospheric pressure. |
