Aircraft turbomachine propeller comprising an autonomous heating element supply system for defrosting and associated method

Abstract

An aircraft turbomachine propeller comprising a cone extending axially along an axis (X) and blades, the propeller being configured to be driven in rotation by a shaft of the turbomachine (A), the propeller comprising a plurality of heating members (2) and an electrical power supply system (3) for the heating members (2), the electrical power supply system (3) being mounted in the cone and configured to generate electrical energy autonomously from the rotation of the shaft of the turbomachine (A). Abstract figure: Figure 2

Description

Title of the invention: Aircraft turbomachine propeller comprising an autonomous heating element supply system for defrosting and associated method Technical field

[0001] The present invention relates to the de-icing of a propeller of a turbomachine of an aircraft.

[0002] In a known manner, an aircraft comprises one or more turbomachines to enable propulsion. A turbomachine comprises at least one rotary shaft configured to drive a propeller in rotation, in particular, via a speed reducer known to those skilled in the art under the designation RGB for "Reduction Gear Box". In a known manner, a propeller comprises an axially extending cone from which a plurality of radial blades extend.

[0003] During the flight of the aircraft, frost is likely to form on the propeller blades. To remove it, it is known to equip the propeller blades with a plurality of heating members. In a known manner, a heating member is in the form of a heating mat comprising a plurality of resistors which are positioned on the leading edge of the blade but also on the cone. In the presence of icing conditions, the heating members are activated intermittently in order to separate the layers of frost. The layers of frost are then ejected due to the centrifugal force linked to the rotation of the propeller.

[0004] The heating elements are electrically powered and it is necessary to provide significant electrical power in order to de-ice the propeller optimally. The electrical power is supplied to the de-icing system by an electrical source internal to the aircraft or the turbomachine. In practice, the electrical source is positioned in a fixed reference frame while the heating elements are positioned in a rotating reference frame linked to the blades. To allow the transfer of energy, it is necessary to provide a rotating transformer. The rotating transformer is connected to an electrical source via power harnesses. The installation of power harnesses from the electrical source to the transformer is complex and increases the mass and size of the turbomachine. This is particularly penalizing during maintenance operations.Furthermore, routing power harnesses through several parts of the turbomachine is problematic since they require the creation of bending radii that are often unfeasible given the limited space requirements.

[0005] The invention aims to eliminate at least some of these drawbacks by proposing a heating element power supply system that is simple to install and maintain while having reduced mass and volume. PRESENTATION OF THE INVENTION

[0006] The invention relates to an aircraft turbomachine propeller comprising a cone extending axially along an axis and blades, the propeller being configured to be driven in rotation by a shaft of the turbomachine, the propeller comprising a plurality of heating members and a system for electrically supplying the heating members.

[0007] The invention is remarkable in that the electrical power system is mounted in the cone and configured to generate electrical energy autonomously from the rotation of the turbomachine shaft.

[0008] Thanks to the invention, it is not necessary to provide a power harness, which limits the mass and size of the power system. Furthermore, since the electrical power system is autonomous, there is no need to carry out time-consuming connection steps with power harnesses. An electrical power system can be replaced in a practical manner. Mounting in the cone is advantageously accessible. Advantageously, this makes it possible to carry out de-icing without taking into account the main electrical sources of the aircraft, which has advantages for their dimensioning by limiting the integration constraints between the turbomachine and the aircraft.

[0009] Advantageously, the electrical energy is generated directly in a rotating reference frame integral with the cone, which makes it possible to do without a converter.

[0010] According to one aspect, the electrical power supply system comprises a permanent magnet synchronous generator configured to generate electrical energy autonomously from the rotation of the shaft of the turbomachine. Such a generator makes it possible to generate an electrical current making it possible to power the heating members.

[0011] According to one aspect, the permanent magnet synchronous generator comprises a first stator fulfilling an inductor function and a first rotor fulfilling an armature function, the first rotor being integral in rotation with the shaft of the turbomachine. Thus, unlike a traditional permanent magnet synchronous generator, the first stator fulfills the inductor function and not the first rotor. This makes it possible to generate an electric current directly in the first rotor in order to power the heating members directly in the rotating reference frame. It is advantageous to do without a rotating transformer which requires an alternative electrical source and harnesses to route the electrical power supply to the transformer. Preferably, the first stator fulfills an inductor function magnets.

[0012] Preferably, the first rotor extends radially outwardly to the first stator. This makes it possible to supply the heating members located at the outer periphery of the propeller as closely as possible.

[0013] In one aspect, the armature is positioned radially outside and the inductor (magnets) is positioned radially inside.

[0014] According to one aspect, the electrical power system comprises a single electrical machine, in particular, only a permanent magnet synchronous generator.

[0015] According to one aspect, the electrical power supply system comprises an electrical power supply machine comprising a second stator fulfilling an inductor function and a second rotor fulfilling an armature function, the second rotor being rotationally fixed to the shaft of the turbomachine, the second stator being powered from the permanent magnet synchronous generator. Preferably, the second stator is wound.

[0016] A two-stage electrical power supply system advantageously makes it possible to avoid the use of a rotating converter in the rotating reference frame. The electrical power supply machine makes it possible to supply a supply current directly to the heating members. The electrical power supply machine has a wound inductor and requires a power supply to become autonomous.

[0017] According to one aspect, the second rotor extends radially outwardly to the second stator. This makes it possible to naturally synchronize the supply of energy to the rotating reference point and to supply the heating members located at the outer periphery of the propeller as closely as possible.

[0018] According to one aspect, the second stator is powered by the first stator of the permanent magnet synchronous generator.

[0019] According to one aspect, the electrical power supply system comprises a control computer configured to convert the supply current supplied by the permanent magnet synchronous generator according to the supply current of the heating members. Preferably, the control computer directly supplies the second stator. In this case, the control computer preferably belongs to the fixed reference.

[0020] According to one aspect, the electrical power supply machine is positioned downstream of the permanent magnet synchronous generator. This makes it possible to limit the overhang by positioning the heaviest equipment downstream.

[0021] According to one aspect, the electrical power supply system comprises an electrical excitation machine comprising a third stator fulfilling an inductor function and a third rotor fulfilling an armature function, the third rotor being rotationally fixed to the shaft of the turbomachine, the third stator being powered by the permanent magnet synchronous generator, the first rotor powering the excitation electric machine which powers the supply electric machine so as to form a three-stage power supply system. In other words, the power supply system has three generators in cascade which share in common a fixed shaft and a rotating shaft.

[0022] According to one aspect, the excitation electric machine is positioned upstream of the supply electric machine, preferably downstream of the permanent magnet synchronous generator. This makes it possible to limit the overhang by positioning the heaviest equipment downstream.

[0023] According to one aspect, the third rotor extends radially outwardly of the third stator.

[0024] According to one aspect, the propeller comprising a fixed reference mark and a rotating reference mark integral in rotation with the cone, each rotor belongs to the rotating reference mark while each stator belongs to the fixed reference mark.

[0025] According to one aspect, the electrical power supply system comprises a control computer configured to convert the supply current supplied by the permanent magnet synchronous generator according to the supply current of the heating members.

[0026] According to one aspect, the electrical power system comprises a defrost controller configured to provide the control computer with a power command, the control computer being configured to convert the supply current provided by the permanent magnet synchronous generator according to the supply current of the heating members and the power command.

[0027] According to one aspect, the control computer is powered by the first rotor of the permanent magnet synchronous generator and the third rotor is powered by the control computer. In this case, the control computer preferably belongs to the rotating reference frame.

[0028] According to one aspect, the electrical power supply system comprises an electrical switch connected to a plurality of heating members. The electrical power supply system thus ensures generation and distribution. A sequential control makes it possible to limit the size of the power supply system and allows it to be mounted in the cone. Preferably, the electrical switch is integral with the rotating marker.

[0029] Advantageously, the integration of an electrical switch in the power supply system makes it possible to aggregate all of the heating-related functions within a single piece of equipment, which facilitates installation and also maintenance.

[0030] According to one aspect, the defrost controller is configured to provide the electrical switch with a sequence command to control a sequential power supply to the heaters.

[0031] According to one aspect, the propeller comprises at least one speed reducer mounted between the shaft of the turbomachine and the cone. This advantageously allows the electrical power system to take advantage of the bearings of the speed reducer without integrating bearings specific to the electrical power system. This makes it possible to limit the air gap in the electrical machines and thus improves the reliability of the generation. It nevertheless goes without saying that the electrical power system could comprise its own bearings.

[0032] According to one aspect, the heating members are resistive.

[0033] The invention further relates to a method of using a propeller as presented above, comprising steps consisting of: • Drive the turbomachine shaft in rotation to drive the blades in rotation and • Generate electrical energy from the rotation of the turbomachine shaft in order to electrically power the heating components in order to de-ice the propeller. PRESENTATION OF FIGURES

[0034] The invention will be better understood on reading the description which follows, given by way of example, and referring to the following figures, given by way of non-limiting examples, in which identical references are given to similar objects.

[0035] [Fig.l] is a schematic representation of a propeller with an electrical power supply system for the heating members according to the invention.

[0036] [Fig.2] is a schematic representation of a first embodiment of an electrical power supply system.

[0037] [Fig. 3] is a schematic representation of a second embodiment of an electrical power supply system.

[0038] [Fig.4] is a schematic representation of a third embodiment of an electrical power supply system.

[0039] It should be noted that the figures set out the invention in detail to implement the invention, said figures can of course be used to better define the invention where appropriate. DETAILED DESCRIPTION OF THE INVENTION

[0040] The invention will be presented for an aircraft comprising a plurality of propeller turbo-machines for providing propulsion of the aircraft, in particular, a plurality of turboprops.

[0041] With reference to [Fig.l], there is shown schematically an aircraft turbomachine propeller 1. The propeller 1 comprises a cone 10, extending axially along an axis X, oriented from upstream to downstream in [Fig.l], and blades 11 which extend, in this example, radially relative to the axis X.

[0042] The propeller 1 is configured to be driven in rotation by a shaft of the turbomachine A in order to rotate the blades 11 and generate propulsion work. Preferably, as illustrated in [Fig.l], the propeller 1 comprises a speed reducer RED mounted between the shaft of the turbomachine A and the cone 10 in order to modify the speed ratio. The propeller 1 comprises a fixed reference mark RF and a rotating reference mark RT integral in rotation with the cone 10.

[0043] The propeller 1 comprises a plurality of heating members 2 in order to allow the de-icing of the propeller 1. In a known manner, a heating member 2 is in the form of a heating mat comprising a plurality of resistors which are positioned on a leading edge of a blade 11 and on the cone 10. In the presence of icing conditions, the heating members 2 are activated intermittently in order to separate the layers of frost. The layers of frost are then ejected due to the centrifugal force linked to the rotation of the propeller 1. With reference to [Fig.l], the propeller 1 comprises an electrical power supply system 3 for powering the heating members 2.

[0044] According to the invention, the electrical power supply system 3 is mounted in the cone 10 of the propeller 1 and is autonomous. By autonomous, it is meant that the electrical power supply system 3 generates electrical energy only from the mechanical torque provided by the shaft of the turbomachine A without resorting to an external source as in the prior art. This advantageously makes it possible to do without power supply harnesses which increase the mass, size and complexity. The electrical power supply system 3 can be maintained and replaced in a practical and rapid manner.

[0045] According to one aspect of the invention, with reference to [Fig. 2], the electrical power supply system 3 comprises a permanent magnet synchronous generator 4 configured to generate electrical energy autonomously from the rotation of the shaft of the turbomachine A. The permanent magnet synchronous generator 4 comprises a first stator 41 fulfilling an inductor function and a first rotor 42 fulfilling an armature function, the first rotor 42 being integral in rotation with the shaft of the turbomachine A. This advantageously makes it possible to generate an electric current 14 at the first rotor 42 to power the heating members 2.

[0046] According to a first embodiment, with reference to [Fig. 2], the electrical power supply system 3 comprises an electrical switch 5 connected to a plurality of heating members 2. Advantageously, the electrical switch 5 makes it possible to control the sequential power supply of the heating members 2.

[0047] In this first embodiment, the electrical switch 5 is powered directly by the permanent magnet synchronous generator 4. Hereinafter, the current which supplies the electrical switch 5 is referred to as "supply current 1a".

[0048] In this example, the electrical switch 5 is powered directly by the first rotor 42 of the permanent magnet synchronous generator 4 (Ia=I4). According to one aspect, the electrical power supply system 3 comprises a single electrical machine which is the permanent magnet synchronous generator 4.

[0049] Preferably, the electrical switch 5 further comprises an electrical converter 50, in particular, an active (controlled) rectifier, in order to convert the supply current 1a into direct current. For the sake of clarity and conciseness, the electrical converter is not shown in all embodiments of the invention. It is shown in [Fig. 2] to convert the current from the permanent magnet synchronous generator 4. As illustrated in [Fig. 2], the electrical switch 5 is secured to the rotating reference mark RT to supply the heating members 2. Depending on the architectures, it nevertheless goes without saying that an electrical converter is optional and that the electrical switch 5 could be supplied directly with alternating current. The electrical converter could also be passive (not controlled) and be, for example, in the form of a diode bridge.

[0050] Still with reference to [Fig.2], the power system 3 further comprises a defrosting controller 6 configured to define the defrosting strategy, in particular, a power command C1 and a sequence command C2 which are sent to the electrical switch 5. In this example, the electrical switch 5 comprises a power converter 50 which receives the power command C1 to adjust the desired power.

[0051] The first rotor 42 of the permanent magnet synchronous generator 4 belongs to the rotating reference frame RT while the first stator 41 of the permanent magnet synchronous generator 4 belongs to the fixed reference frame RF. In this example, the first rotor 42 and the electrical switch 5 are connected to a rotating casing 12. The permanent magnet synchronous generator 4 is of the “inverted” type since the first rotor 42 extends radially outwardly to the first stator 41 relative to the axis X. As illustrated in [Fig. 2], the permanent magnet synchronous generator 4 comprises a plurality of magnets 410 at the periphery of its first stator 4L. Such an architecture makes it possible to naturally synchronize the supply of electrical energy with the rotating reference frame RT without adding an additional device such as a rotating transformer in the prior art.

[0052] Such a power supply system 3 is advantageous since it comprises little equipment and allows easy and practical maintenance. The power supply system 3 is advantageously autonomous. During the rotation of the turbomachine shaft A, the rotating casing 12 is also driven, preferably, via the reducer RED.

[0053] The rotation of the first rotor 42 of the permanent magnet synchronous generator 4 makes it possible to generate an induced current 14 by magnetic interaction with the magnets 410 of the first stator 41 which belongs to the fixed reference frame RF.

[0054] The induced current 14 corresponds to the supply current 1a of the electrical switch 5. The defrost controller 6 sends a power command C1 and a sequence command C2 to the electrical switch 5 which makes it possible to define the control strategy of the heating members 2, i.e., the power and the defrosting time delay.

[0055] Thanks to the invention, it is not necessary to provide a passage for power supply harnesses. The electrical power supply system 3 is autonomous and independent. This makes it possible to make the de-icing members independent of the aircraft's generation and distribution system, which avoids oversizing and limits constraints.

[0056] In this first embodiment, the permanent magnet synchronous generator 4 is associated with a power converter 50 controlled in the rotating reference frame RT to manage the power level to be supplied to the heating members 2. This affects the reliability and availability of the electrical power supply system 3. In this embodiment, the permanent magnet synchronous generator 4 must remain active permanently even in non-icing conditions, which increases the fire risk and limits the lifespan of the latter.

[0057] A second embodiment is shown in [Fig. 3]. For the sake of clarity and conciseness, elements identical or similar to the first embodiment are not described again.

[0058] According to the second embodiment, with reference to [Fig. 3], the electrical power supply system 3 further comprises an electrical power supply machine 7 comprising a second stator 71 fulfilling an inductor function and a second rotor 72 fulfilling an armature function. The second rotor 72 is rotationally fixed to the shaft of the turbomachine A. The second stator 71 is powered by the permanent magnet synchronous generator 4, in particular, via the first stator 4L

[0059] A two-stage architecture advantageously makes it possible to reduce the size of the permanent magnet synchronous generator 4, in particular, by eliminating the power converter 50 shown in [Fig.2], which allows an overall reduction in the mass and size of the electrical power supply system 3.

[0060] In order to control the power supply power, the power supply system 3 further comprises a control computer 8. As illustrated in [Fig.3] , the second stator 71 is powered indirectly by the permanent magnet synchronous generator 4 via the control computer 8.

[0061] As illustrated in [Fig.3], the permanent magnet synchronous generator 4 generates an alternating current 14 in the first stator 41 which is transformed by the control computer 8 into a direct current 18 to supply the second stator 71 and generate an alternating current 17 in the second rotor 72 in order to supply the electrical switch 5 (Ia=I7).

[0062] Since the first stator 41 and the second stator 71 belong to the fixed frame RF, it is advantageous to place the control computer 8 in the fixed frame RF as illustrated in [Fig. 3]. In this example, the control computer 8 comprises an electrical converter of the rectifier type. Optionally, with reference to [Fig. 3], the control computer 8 can also supply direct or alternating current to other auxiliary electrical loads AUX.

[0063] The control computer 8 is configured to receive the power command C1 from the defrosting controller 6 so as to precisely determine the current 18 to be supplied to the second stator 71.

[0064] According to one aspect, as illustrated in [Fig. 3], the control computer 8 is connected to a current sensor 80 configured to measure the current 17 supplied by the second rotor 72 of the electrical supply machine 7. This advantageously allows the control computer 8 to determine the current 18 to be supplied to the second stator 71 by servocontrol from the power command C1 and the supply current 1a (current 17 supplied by the second rotor 72).

[0065] Since the second rotor 72 belongs to the rotating reference frame RT and the control computer 8 belongs to the fixed reference frame RF, it is preferable to use a contactless inductive sensor 80. It goes without saying that the control computer 8 could measure any physical quantity (current or voltage) which is an image of the current 17.

[0066] In this second embodiment, the permanent magnet synchronous generator 4 and the control computer 8 are sized to directly supply the excitation power to the electrical supply machine 7, i.e. approximately 1 / 10th of the power of the heating members 2.

[0067] A third embodiment is shown in [Fig. 4]. For the sake of clarity and conciseness, elements identical or similar to the second embodiment are not described again.

[0068] According to the third embodiment, with reference to [Fig. 4], the electrical power supply system 3 further comprises an electrical excitation machine 9 comprising a third stator 91 fulfilling an armature function and a third rotor 92 fulfilling an inductor function. The third rotor 92 is integral in rotation with the shaft of the turbomachine A.

[0069] The third rotor 92 is powered by the permanent magnet synchronous generator 4, in particular, via the first rotor 42. Such a power supply is practical given that they all belong to the rotating reference frame RT.

[0070] In this example, the third rotor 92 of the excitation electric machine 9 is powered indirectly by the first rotor 42 of the permanent magnet synchronous generator 4 via the control computer 8. As illustrated in [Fig.4], the permanent magnet synchronous generator 4 generates an alternating current 14 in the first rotor 42 which is transformed by the control computer 8 into direct current 18 to power the third rotor 92.

[0071] The second stator 71 of the power supply electrical machine 7 is powered by the third stator 91 of the excitation electrical machine 9 as illustrated in [Fig.4]. Preferably, the third stator 91 of the excitation electrical machine 9 generates an alternating current which is rectified via a rectifier 93 to supply the second stator 71 of the power supply electrical machine 7 with a direct current 19. In this example, the rectifier 93 is in the form of a diode bridge. The power supply electrical machine 7 generates an alternating current 17 in the second rotor 72 in order to supply the electrical switch 5 (Ia=I7).

[0072] A three-stage architecture advantageously makes it possible to reduce overall the mass and size of the electrical power supply system 3. With this architecture, the permanent magnet synchronous generator 4 and the electrical excitation machine 9 are small in size compared to the second embodiment of [Fig. 3] (approximately 1 / 100th of the power of the heating members 2).

[0073] In the first embodiment, the permanent magnet synchronous generator 4 is the main (and only) equipment that supplies the electrical power to the heating members 2. In the second embodiment, the permanent magnet synchronous generator 4 is a secondary source of excitation for the power supply electric machine 7. The permanent magnet synchronous generator 4 supplies approximately 10% of the electrical power to the heating members 2. In the third embodiment, the permanent magnet synchronous generator 4 is also a secondary source of excitation for the power supply electric machine 7. The permanent magnet synchronous generator 4 supplies approximately 1% of the electrical power to the heating members 2.

[0074] Since the first rotor 42 and the third rotor 92 belong to the rotating reference frame RT, it is advantageous to place the control computer 8 in the rotating reference frame RT as illustrated in [Fig.4].

[0075] In a similar manner to previously, the control computer 8 is configured to receive the power command C1 from the defrosting controller 6 so as to precisely determine the current 18 to be supplied to the third rotor 92.

[0076] According to one aspect, as illustrated in [Fig. 4], the control computer 8 is connected to a current sensor 81 configured to measure the current 17 (mI7) supplied by the second rotor 72 of the electrical supply machine 7. This advantageously allows the control computer 8 to determine the current 18 to be supplied to the third rotor 92 by servocontrol from the power command C1 and the measurement mI7 of the supply current 1a (current 17 supplied by the second rotor 72). Given that the third rotor 92 belongs to the rotating reference frame RT and that the control computer 8 belongs to the rotating reference frame RT, a traditional current sensor 81 can be advantageously used.

[0077] A three-stage 3-power supply system allows for simple and convenient integration to maintain while allowing for weight and mass savings.

[0078] In order to allow optimal cooling of the electrical power supply system 3, several cooling devices may advantageously be provided. For example, a fan may be mounted in the cone 10 to cool the electrical equipment 4, 7, 9. Similarly, the rotating casing 12 may be equipped with cooling fins. Advantageously, the speed reducer comprises a cooling circuit, for example an oil circuit, which supplies a cooling circuit of the electrical power supply system in a synergistic manner.

Claims

Claims

1. Propeller (1) of an aircraft turbomachine comprising a cone (10) extending axially along an axis (X) and blades (11), the propeller (1) being configured to be driven in rotation by a shaft of the turbomachine (A), the propeller comprising a plurality of heating members (2) and an electrical power supply system (3) for the heating members (2), the electrical power supply system (3) being mounted in the cone (10) and configured to generate electrical energy autonomously from the rotation of the shaft of the turbomachine (A), the electrical power supply system (3) comprising a permanent magnet synchronous generator (4) configured to generate electrical energy autonomously from the rotation of the shaft of the turbomachine (A), the permanent magnet synchronous generator (4) comprises a first stator (41) fulfilling an inductor function and a first rotor (42) fulfilling an armature function,the first rotor (42) being integral in rotation with the shaft of the turbomachine (A), the electrical power supply system (3) comprising: • an electrical power supply machine (7) comprising a second stator (71) fulfilling an inductor function and a second rotor (72) fulfilling an armature function, the second rotor (72) being integral in rotation with the shaft of the turbomachine (A), the second stator (71) being powered from a permanent magnet synchronous generator (4).,

2. Propeller (1) according to claim 1 in which the first rotor (42) extends radially outwardly to the first stator (41).

3. Propeller (1) according to one of claims 1 to 2 in which the second rotor (72) extends radially outwardly to the second stator (71).

4. Propeller (1) according to one of claims 1 to 3 in which the electrical power supply system (3) comprises an electrical excitation machine (9) comprising a third stator (91) fulfilling an inductor function and a third rotor (92) fulfilling an armature function, the third rotor (92) being rotationally fixed to the shaft of the turbomachine (A), the third stator (91) being powered by the permanent magnet synchronous generator (4), the first rotor (42) powering the excitation electric machine (9) which powers the supply electric machine (7) so as to form a three-stage electric power system (3).

5. Propeller (1) according to one of claims 1 to 4, comprising a fixed reference mark (RF) and a rotating reference mark (RT) integral in rotation with the cone (10), each rotor (42, 72, 92) belongs to the rotating reference mark (RT) while each stator (41, 71, 91) belongs to the fixed reference mark (RF).

6. Propeller (1) according to one of claims 1 to 5, in which the electrical power supply system (3) comprises a control computer (8) configured to convert the supply current supplied by the permanent magnet synchronous generator (4) as a function of the supply current of the heating members (2).

7. Propeller (1) according to claim 6, in which the electrical power supply system (3) comprises a defrosting controller (6) configured to provide the control computer (8) with a power command (Cl), the control computer (8) being configured to convert the supply current supplied by the permanent magnet synchronous generator (4) as a function of the supply current of the heating members (2) and of the power command (Cl).

8. Propeller (1) according to one of claims 1 to 7, in which the electrical power supply system (3) comprises an electrical switch (5) connected to a plurality of heating members (2).

9. Method of using a propeller (1) according to one of claims 1 to 8, comprising steps consisting of: • Driving the turbomachine shaft (A) in rotation to drive the blades (11) in rotation and • Generating electrical energy from the rotation of the turbomachine shaft (A) so as to electrically power the heating members (2) in order to de-ice the propeller (1).

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