Patent ID: 8442740

Claim:
A method of regulating a power plant having a gas generator and a free turbine in a rotary wing aircraft, the method comprising: using a measured value of a first speed of rotation (NTL) of the free turbine to cause the first speed of rotation (NTL) to tend towards a first setpoint value (NTL*) by controlling a second speed of rotation (NG) of said gas generator by a second setpoint value (NG*); monitoring variation in a collective pitch of blades of the rotary wing and, as a function of said variation, temporarily anticipating a power demand of the rotary wing by correcting the second setpoint value (NG*); reading a current value of a third speed of rotation (NR) of the rotary wing to calculate a regulation term (NRc) that is a function of the third speed of rotation (NR) by using the following relationship: NRc=NR *(1− d ) where “NRc” represents said regulation term, “NR” represents said third speed of rotation, and “d” represents a non-zero constant lying in the range 0 to 1; comparing the values of the regulation term (NRc) with a predetermined setpoint threshold (NTL′) of the first speed of rotation (NTL) of the free turbine; and regulating the first speed of rotation (NTL) of the free turbine on a first setpoint value (NTL*) equal either to said regulation term (NRc) or to said setpoint threshold (NTL′), as a function of predetermined conditions.