Abstract: An electronic control system (35) for a turbopropeller (2) having a gas turbine engine (20) and a propeller assembly (3) coupled to the gas turbine engine (20), the control system (35) having: a propeller control stage (35a), implementing a closed loop control for controlling operation of the propeller assembly (3) based on a scheduled propeller speed reference (Nrref) and a propeller speed measure (Nr); a gas turbine control stage (35b), implementing a closed loop control for controlling operation of the gas turbine engine (20) based on a scheduled reference (Ngdotref) and at least a feedback quantity. The control system (35) further envisages an auxiliary control stage (35c), coupling the propeller control stage (35a) and the gas turbine control stage (35b) and determining a limitation of the operation of the gas turbine engine (20), if a propeller speed overshoot is detected, with respect to the propeller speed reference (Nrref).

Abstract: In a fuel control system (10) for a gas turbine engine (1) having a gas generator (4) and a turbine (6) driven by the gas generator (4): a main fuel regulator (12) determines a demand (Wfdem) of fuel flow (Wf) to be introduced in the gas turbine engine (1), based on an input request (PLA); and a first limiter stage (14), operatively coupled to the main fuel regulator (12), causes an adjustment of the fuel flow (Wf) based on engine safety operating limits. The first limiter stage (14) is provided with a Ngdot limiter (20) to cause an adjustment of the fuel flow (Wf) when the gas generator speed rate of change (Ngdot) is determined to overcome acceleration/deceleration scheduled safety limits; the Ngdot limiter (20) implements a predictor (23), to perform a prediction (Wfdot) of the fuel flow rate of change (Wfdot), or fuel flow (Wf), allowing the gas generator speed rate of change (Ngdot) to track a scheduled reference value (Ngdotref).

Abstract: An electronic control system (30) for a turbopropeller engine (12) having a gas turbine (20) and a propeller assembly (13) coupled to the gas turbine (20), controls propeller operation based on a pilot input request, via generation of a driving quantity (Ip) for an actuation assembly (29) designed to adjust a pitch angle (?) of propeller blades (2) of the propeller assembly (13).

Abstract: An electronic control system for a turbopropeller engine having a gas turbine and a propeller assembly coupled to the gas turbine is provided. The control system implements a propeller control unit to control propeller operation using an actuation assembly designed to adjust a pitch angle of propeller blades. The control unit engages a mechanical lock determining a minimum flight value for the pitch angle during a flight operating mode, and disengages the mechanical lock and controls the pitch angle below the minimum flight value, up to a minimum ground value lower than the minimum flight value, during a ground operating mode. The propeller control unit, during a transition from the ground operating mode to the flight operating mode, engages the mechanical lock. The control unit anticipates the increase of the pitch angle before the mechanical lock engagement when transitioning from the ground operating mode to the flight operating mode.

Abstract: A control system (50) for a turbopropeller engine (2) of an aircraft (1) having a gas turbine (11) and a propeller assembly (3) coupled to the gas turbine (11), the gas turbine (11) having a compressor (12) coupled to an air intake (13) and a temperature sensor (22) being arranged in the air intake (13) to measure the temperature of engine intake air and provide a sensed temperature (T1sens); the control system envisages: a compensation system (40) to receive the sensed temperature (T1sens) from the temperature sensor (22) and to add to the sensed temperature (T1sens) a compensation quantity (comp) to compensate for a delay introduced by the time constant (?) of the temperature sensor (22) and generate a compensated temperature (T1comp); and a control unit (20) to perform engine control operations based on the compensated temperature (T1comp).

Abstract: In a fuel control system (10) for a gas turbine engine (1) having a gas generator (4) and a turbine (6) driven by the gas generator (4): a main fuel regulator (12) determines a demand (Wfdem) of fuel flow (Wf) to be introduced in the gas turbine engine (1), based on an input request (PLA); and a first limiter stage (14), operatively coupled to the main fuel regulator (12), causes an adjustment of the fuel flow (Wf) based on engine safety operating limits. The first limiter stage (14) is provided with a Ngdot limiter (20) to cause an adjustment of the fuel flow (Wf) when the gas generator speed rate of change (Ngdot) is determined to overcome acceleration/deceleration scheduled safety limits; the Ngdot limiter (20) implements a predictor (23), to perform a prediction (Wfdot) of the fuel flow rate of change (Wfdot), or fuel flow (Wf), allowing the gas generator speed rate of change (Ngdot) to track a scheduled reference value (Ngdotref).

Abstract: A control system (50) for an electro-hydraulic servo-actuator (26) envisages: a controller (55), to generate a control current (Ic), designed to control actuation of the electro-hydraulic servo-actuator (26), implementing a position control loop based on a position error (ep), the position error (ep) being a difference between a reference position (Posref) and a measured position (Posmeas) of the electro-hydraulic servo-actuator (26); and a limitation stage (58), coupled to the controller (55) to provide a limitation of the actuator speed of the electro-hydraulic servo-actuator (26); the limitation stage (58) limits a rate of change of a driving current (Id) to be supplied to the electro-hydraulic servo-actuator (26), in order to limit the actuator speed.

Abstract: In a fuel control system (10) for a gas turbine engine (1) having a gas generator (4) and a turbine (6) driven by the gas generator (4): a main fuel regulator (12) determines a demand (Wfdem) of fuel flow (Wf) to be introduced in the gas turbine engine (1), based on an input request (PLA); and a first limiter stage (14), operatively coupled to the main fuel regulator (12), causes an adjustment of the fuel flow (Wf) based on engine safety operating limits. The first limiter stage (14) is provided with a Ngdot limiter (20) to cause an adjustment of the fuel flow (Wf) when the gas generator speed rate of change (Ngdot) is determined to overcome acceleration/deceleration scheduled safety limits; the Ngdot limiter (20) implements a predictor (23), to perform a prediction (Wfdot) of the fuel flow rate of change (Wfdot), or fuel flow (Wf), allowing the gas generator speed rate of change (Ngdot) to track a scheduled reference value (Ngdotref).

Abstract: An electronic control system (30) for a turbopropeller engine (1) having a gas turbine (2, 4, 5, 6) and a propeller (7), coupled to the gas turbine, the control system (10) having a propeller control unit (14) and a turbine control unit (15) to jointly control engine power output based on an input request (PLA), wherein the propeller control unit (14) has a first reference generator (16), to determine a reference propeller speed (Npref) based on the input request (PLA), and a first regulator (19), to regulate a propeller speed (Np). The propeller control unit (14) has a reference correction stage (31) to apply a correction to the reference propeller speed (Npref) and generate thereby a corrected reference propeller speed (I), and the first regulator (19) regulates the propeller speed (Np) based on the corrected reference propeller speed (I) to achieve optimized efficiency.

Abstract: A control system (50) for an electro-hydraulic servo-actuator (26) envisages: a controller (55), to generate a control current (Ic), designed to control actuation of the electro-hydraulic servo-actuator (26), implementing a position control loop based on a position error (ep), the position error (ep) being a difference between a reference position (Posref) and a measured position (Posmeas) of the electro-hydraulic servo-actuator (26); and a limitation stage (58), coupled to the controller (55) to provide a limitation of the actuator speed of the electro-hydraulic servo-actuator (26); the limitation stage (58) limits a rate of change of a driving current (Id) to be supplied to the electro-hydraulic servo-actuator (26), in order to limit the actuator speed.

Abstract: In a fuel control system (10) for a gas turbine engine (1) having a gas generator (4) and a turbine (6) driven by the gas generator (4): a main fuel regulator (12) determines a demand (Wfdem) of fuel flow (Wf) to be introduced in the gas turbine engine (1), based on an input request (PLA); and a first limiter stage (14), operatively coupled to the main fuel regulator (12), causes an adjustment of the fuel flow (Wf) based on engine safety operating limits. The first limiter stage (14) is provided with a Ngdot limiter (20) to cause an adjustment of the fuel flow (Wf) when the gas generator speed rate of change (Ngdot) is determined to overcome acceleration/deceleration scheduled safety limits; the Ngdot limiter (20) implements a predictor (23), to perform a prediction (Wfdot) of the fuel flow rate of change (Wfdot), or fuel flow (Wf), allowing the gas generator speed rate of change (Ngdot) to track a scheduled reference value (Ngdotref).

Abstract: A control system (50) for a turbopropeller engine (2) of an aircraft (1) having a gas turbine (11) and a propeller assembly (3) coupled to the gas turbine (11), the gas turbine (11) having a compressor (12) coupled to an air intake (13) and a temperature sensor (22) being arranged in the air intake (13) to measure the temperature of engine intake air and provide a sensed temperature (T1sens); the control system envisages: a compensation system (40) to receive the sensed temperature (T1sens) from the temperature sensor (22) and to add to the sensed temperature (T1sens) a compensation quantity (comp) to compensate for a delay introduced by the time constant (?) of the temperature sensor (22) and generate a compensated temperature (T1comp); and a control unit (20) to perform engine control operations based on the compensated temperature (T1comp).

Abstract: An electronic control system (35) for a turbopropeller (2) having a gas turbine engine (20) and a propeller assembly (3) coupled to the gas turbine engine (20), the control system (35) having: a propeller control stage (35a), implementing a closed loop control for controlling operation of the propeller assembly (3) based on a scheduled propeller speed reference (Nrref) and a propeller speed measure (Nr); a gas turbine control stage (35b), implementing a closed loop control for controlling operation of the gas turbine engine (20) based on a scheduled reference (Ngdotref) and at least a feedback quantity. The control system (35) further envisages an auxiliary control stage (35c), coupling the propeller control stage (35a) and the gas turbine control stage (35b) and determining a limitation of the operation of the gas turbine engine (20), if a propeller speed overshoot is detected, with respect to the propeller speed reference (Nrref).

Abstract: An electronic control system (30) for a turbopropeller engine (12) having a gas turbine (20) and a propeller assembly (13) coupled to the gas turbine (20), controls propeller operation based on a pilot input request, via generation of a driving quantity (Ip) for an actuation assembly (29) designed to adjust a pitch angle (?) of propeller blades (2) of the propeller assembly (13).

Abstract: An electronic control system (35) for a turbopropeller engine (2) having a gas turbine (20) and a propeller assembly (3) coupled to the gas turbine (20), the control system (35) implementing a propeller control unit (PEC) to control propeller operation based on a pilot input request, via generation of a driving quantity (Ip) for an actuation assembly (29) designed to adjust a pitch angle (?) of propeller blades (10). The control unit engages a mechanical lock determining a minimum flight value for the pitch angle during a flight operating mode, and disengages the mechanical lock and controls the pitch angle below the minimum flight value, up to a minimum ground value lower than the minimum flight value, during a ground operating mode; the propeller control unit, during a transition from the ground operating mode to the flight operating mode, engages the mechanical lock, thereby causing an increase of the pitch angle towards the minimum flight value independently from the control action.

Abstract: An electronic control system (30) for a turbopropeller engine (1) having a gas turbine (2, 4, 5, 6) and a propeller (7), coupled to the gas turbine, the control system (10) having a propeller control unit (14) and a turbine control unit (15) to jointly control engine power output based on an input request (PLA), wherein the propeller control unit (14) has a first reference generator (16), to determine a reference propeller speed (Npref) based on the input request (PLA), and a first regulator (19), to regulate a propeller speed (Np). The propeller control unit (14) has a reference correction stage (31) to apply a correction to the reference propeller speed (Npref) and generate thereby a corrected reference propeller speed (I), and the first regulator (19) regulates the propeller speed (Np) based on the corrected reference propeller speed (I) to achieve optimized efficiency.