Control device and control method of hybrid vehicle

A control method performed by a control device of a hybrid vehicle using an internal combustion engine, which purifies exhaust gas with a catalyst, as at least one power source, wherein the hybrid vehicle can run by performing an intermittent operation for temporarily stopping the internal combustion engine and the catalyst has a characteristic that second temperature of the catalyst necessary for exhaust gas purification at starting of the internal combustion engine is higher than first temperature of the catalyst necessary for the exhaust gas purification during a continuous operation of the internal combustion engine, the control method comprising:

• an obtaining step for obtaining temperature of the catalyst;
• and
• a controlling step for controlling the internal combustion engine in either one of modes of a normal operation mode, a warm-up operation mode and an intermittency prohibition operation mode based on the temperature of the catalyst, wherein the normal operation allows the intermittent operation, the warm-up operation increases fuel supply quantity to the internal combustion engine from the fuel supply quantity of the normal operation while prohibiting the intermittent operation, and the intermittency prohibition operation prohibits the intermittent operation while setting the fuel supply quantity to be the same as the fuel supply quantity of the normal operation, wherein
• the controlling step performs the warm-up operation if the temperature of the catalyst is lower than the first temperature,
• the controlling step performs the intermittency prohibition operation if the temperature of the catalyst is between the first temperature and the second temperature, and
• the controlling step performs the normal operation if the temperature of the catalyst is higher than the second temperature.