Internal combustion engine control device and control method

A control device for an internal combustion engine, the internal combustion engine to which the control device is applied including a port injection valve that injects fuel into an intake passage and a catalyst that purifies exhaust gas discharged to an exhaust passage, wherein the control device is configured to execute:

• a multiple injection process for executing an intake synchronous injection and an intake asynchronous injection to inject fuel of a requested injection amount for controlling an air-fuel ratio to a target air-fuel ratio by operating the port injection valve, the requested injection amount being requested in a single combustion cycle, the intake synchronous injection injecting fuel in synchronization with an open period of an intake valve, the intake asynchronous injection injecting fuel at a timing advanced with respect to a timing of the intake synchronous injection;
• and
• an advancement process for setting the injection timing of the intake synchronous injection to be more advanced when a temperature of the catalyst is low than when the temperature of the catalyst is high.

A control method for an internal combustion engine, the internal combustion engine including a port injection valve that injects fuel into an intake passage, wherein the control method comprises:

• executing an intake synchronous injection and an intake asynchronous injection to inject fuel of a requested injection amount by operating the port injection valve, the requested injection amount being requested in a single combustion cycle, the intake synchronous injection injecting fuel in synchronization with an open period of an intake valve, the intake asynchronous injection injecting fuel at a timing advanced with respect to a timing of the intake synchronous injection;
• and
• variably setting an injection timing of the intake synchronous injection based on at least two parameters of three parameters, the injection timing of the intake synchronous injection being represented by a rotation angle of a crankshaft of the internal combustion engine, the three parameters referring to a rotation speed of the crankshaft of the internal combustion engine, an opening start timing of the intake valve that changes an overlap amount of the intake valve and an exhaust valve, and a temperature of an intake system of the internal combustion engine.

A control method for an internal combustion engine, the internal combustion engine to which the control method is applied including a port injection valve that injects fuel into an intake passage and a catalyst that purifies exhaust gas discharged to an exhaust passage, wherein the method comprises:

• executing an intake synchronous injection and an intake asynchronous injection to inject fuel of a requested injection amount for controlling an air-fuel ratio to a target air-fuel ratio by operating the port injection valve, the requested injection amount being requested in a single combustion cycle, the intake synchronous injection injecting fuel in synchronization with an open period of an intake valve, the intake asynchronous injection injecting fuel at a timing advanced with respect to a timing of the intake synchronous injection;
• and
• setting the injection timing of the intake synchronous injection to be more advanced when a temperature of the catalyst is low than when the temperature of the catalyst is high.

A non-transitory computer-readable medium that stores a program for causing a processor to execute a control process for an internal combustion engine, the internal combustion engine including a port injection valve that injects fuel into an intake passage, the control process comprises:

• executing an intake synchronous injection and an intake asynchronous injection to inject fuel of a requested injection amount by operating the port injection valve, the requested injection amount being requested in a single combustion cycle, the intake synchronous injection injecting fuel in synchronization with an open period of an intake valve, the intake asynchronous injection injecting fuel at a timing advanced with respect to a timing of the intake synchronous injection;
• and
• variably setting an injection timing of the intake synchronous injection based on at least two parameters of three parameters, the injection timing of the intake synchronous injection being represented by a rotation angle of a crankshaft of the internal combustion engine, the three parameters referring to a rotation speed of the crankshaft of the internal combustion engine, an opening start timing of the intake valve that changes an overlap amount of the intake valve and an exhaust valve, and a temperature of an intake system of the internal combustion engine.