ENGINE ROTATIONAL SPEED CONTROL APPARATUS

A rotational speed control apparatus for an engine (10) is provided. The engine (10) is configured to drive a compressor that compresses a cooling medium for air conditioning. The rotational speed control apparatus includes electronic control unit (25). The electronic control unit (25) is configured to: (a) correct a torque of the engine (10) through feedback in accordance with a deviation between a rotational speed during idle operation and a target rotational speed; (b) (i) calculate a load torque of the compressor (24), and (ii) correct the calculated load torque through feedback in accordance with a deviation between the rotational speed of the engine (10) and the target rotational speed and correct a required value of the torque of the engine (10) in accordance with the corrected load torque, in a predetermined period from a start of a changeover between a driven state of the compressor (24) and a stopped state of the compressor (24).