摘要:
A target compression ratio ε(t+Tact) after a prescribed time Tact has expired from a current point of time is calculated from an intake air volume drawn into a cylinder (7) after expiration of the prescribed time Tact from the current point of time. A control command (t) to an electric motor (31) that drives a variable compression ratio mechanism (9) is calculated so as to bring an actual compression ratio εr(t+Tact) after the prescribed time Tact into accordance with the target compression ratio ε(t+Tact) after the prescribed time Tact. This enables the actual compression ratio to follow the target compression ratio accurately.
摘要:
At the time of increasing an actual intake air amount by increasing a valve overlap period of intake and exhaust valves (2; 3), an actual compression ratio is temporarily decreased to be lower than a steady-state target compression ratio. This makes it possible to increase the valve overlap period without causing interference of the intake and exhaust valves (2; 3) with a piston (8).
摘要:
At the time of increasing an actual intake air amount by increasing a valve overlap period of intake and exhaust valves (2; 3), an actual compression ratio is temporarily decreased to be lower than a steady-state target compression ratio. This makes it possible to increase the valve overlap period without causing interference of the intake and exhaust valves (2; 3) with a piston (8).