Engine operation control device for hybrid vehicle

An engine operation control device for a hybrid vehicle, comprising:

• an engine provided in a vehicle;
• a power generator that is driven by the engine to generate electric power;
• a driving battery that is chargeable with electric power supplied from the power generator;
• a driving motor that drives drive wheels with electric power supplied from the driving battery or electric power supplied from the power generator;
• a mode switching unit for switching a travel mode of the vehicle to a series mode in which the driving motor drives the drive wheels to cause the vehicle to travel while the engine is operated at a predetermined set rotational speed to cause the power generator to generate electric power;
• an atmospheric pressure detection unit for detecting atmospheric pressure in a present position of the vehicle;
• and
• a setting unit for setting a rotational speed of the engine so that the set rotational speed increases with decreasing of the atmospheric pressure detected by the atmospheric pressure detection unit in the series mode.