Method for controlling internal combustion engine and device for controlling same

A device for controlling an internal combustion engine, comprising:

• a catalyst converter for purifying exhaust gas;
• a brake booster to which negative pressure is supplied from a downstream of a throttle valve;
• a catalyst temperature sensor for detecting a warm-up state of the catalyst converter;
• a crank angle sensor for detecting whether or not the internal combustion engine is in an idle operation state;
• an atmospheric pressure sensor for detecting an atmospheric pressure;
• and
• an engine controller, wherein the engine controller is configured to
• compare the detected atmospheric pressure with a predetermined atmospheric pressure threshold, and
• at a time of the idle operation in which warm-up of the catalyst converter needs to be promoted, control a throttle valve opening degree to an opening degree so as to obtain a first target intake pressure obtained by adding an amount equivalent to a reduction amount of thermal efficiency, which is required to promote the warm-up of the catalyst converter, to an intake pressure required to maintain a predetermined idle speed, when the atmospheric pressure is higher than the atmospheric pressure threshold, and control the throttle valve opening degree to an opening degree so as to obtain a second target intake pressure that is a highest intake pressure in a range in which a differential pressure required by the brake booster is obtained, when the atmospheric pressure is lower than the atmospheric pressure threshold,
• wherein the atmospheric pressure threshold is set to an atmospheric pressure at an altitude at which the first target intake pressure, which varies according to the altitude, and the second target intake pressure match each other.