Combined-cycle power plant with control of the inlet air temperature and method for controlling a combined-cycle power plant

A combined-cycle power plant includes: a gas turbine assembly (2), having an air intake (18) for suction of an inlet airflow (Q I ); auxiliary devices (10); a closed cooling circuit (11) for cooling the auxiliary devices (10); and an inlet air heating device (12), operable to heat the inlet airflow (Q I ) sucked through the air intake (18); in which the inlet air heating device (12) comprises a heat exchanger (28), arranged along the air intake (18) so as to be hit by the inlet airflow (Q I ) and configured to allow a heat exchange between a working fluid of the closed cooling circuit (11) and the inlet airflow (Q I ) sucked through the air intake (18).