| 摘要 |
The purpose of the present invention is to provide an engine with which calculation errors related to EGR gas weight can be inhibited on the basis of an operation state. Accordingly, provided is an engine (1) which is provided with an EGR device (8) for recirculating, into an intake gas, a portion of an exhaust gas as an EGR gas, said engine (1) wherein: an actual intake/exhaust gas pressure ratio (π1) of an intake-gas pressure (P1) to an exhaust-gas pressure (P2) is calculated from the detected exhaust-gas pressure (P2) and the detected intake-gas pressure (P1); an estimated intake/exhaust gas pressure ratio (π2) of the intake-gas pressure (P1) to the exhaust-gas pressure (P2) is calculated from a rotational frequency (N), i.e. the engine rotational frequency, and an injection amount (F), i.e. the fuel injection amount; and, in cases when the actual intake/exhaust gas pressure ratio (π1) is less than a prescribed value (π0), an EGR gas weight (Megr) is calculated on the basis of the actual intake/exhaust gas pressure ratio (π1), and in cases when the actual intake/exhaust gas pressure ratio (π1) is equal to or more than the prescribed value (π0), the EGR gas weight (Megr) is calculated on the basis of the estimated intake/exhaust gas pressure ratio (π2). |
