STARTING/GENERATING SYSTEM AND METHOD FOR AN AIRCRAFT TURBINE ENGINE

Abstract

A starting/generating system for an aircraft turbine engine, the starting/generating system comprising at least one brushless drive motor/generator, at least one control module and at least one power module, the power module being configured to supply/receive electric power from the brushless drive motor/generator, the control module being connected to the brushless drive motor/generator by a control cable in order to control its operation, in which system the power module is configured to be mounted in the housing of the non-pressurized zone so as to be located adjacent to the brushless drive motor/generator and the control module is configured to be mounted in a pressurized zone of the aircraft, the control module being connected to the power module by a two-way communication cable in order to control its operation.

Claims

1-9. (canceled)

10. A starting/generating system for an aircraft turbine engine, the starting/generating system comprising at least one brushless drive motor/generator, at least one control module and at least one power module, the brushless drive motor/generator being configured to be positioned in a housing in a non-pressurised zone to start an aircraft turbine engine, the power module being configured to be connected to an on-board electrical network of the aircraft, the power module being configured to supply/receive electric power from the brushless drive motor/generator, the control module being connected to the brushless drive motor/generator by a control cable in order to control its operation, system characterised by the fact that: The power module is configured to be mounted in the housing of the non-pressurised zone so as to be located adjacent to the brushless drive motor/generator and The control module is configured to be mounted in a pressurised zone of the aircraft, the control module being connected to the power module by a two-way communication cable in order to control its operation.

11. The system according to claim 10, wherein the control module and the power module are configured to exchange digitally via the two-way communication cable.

12. The system according to claim 10, wherein, the power module comprising at least one inverter-rectifier comprising transistors, the control module comprises a calculation device configured to calculate control duty cycles of the transistors of the inverter-rectifier.

13. The system according to claim 10, wherein, the power module comprises at least one device for measuring one or more of the following parameters of the brushless drive motor/generator: direct voltage in interface with the on-board electrical network, phase current, control signal, speed of a rotor, angular position of a rotor, temperature.

14. The system according to claim 10, wherein, the power module comprising at least one inverter-rectifier comprising transistors, the control module comprising a calculation device configured to calculate control duty cycles of the transistors of the inverter-rectifier and at least one device for measuring one or more of the following parameters of the brushless drive motor/generator: direct voltage in interface with the on-board electrical network, phase current, control signal, speed of a rotor, angular position of a rotor, temperature, the calculation device is configured to calculate the control duty cycles of the transistors of the inverter-rectifier according to one or more parameters measured by the measuring device.

15. The system according to claim 10, wherein the on-board electrical network is of the 28 VDC type.

16. The system according to claim 10, wherein the starting system comprises at least one cooling module, mounted in the housing, configured to cool the brushless drive motor/generator and the power module.

17. The aircraft comprising at least one turbine engine, at least one starting/generating system according to claim 10, at least one pressurised zone and at least one non-pressurised zone, the control module of the starting/generating system being mounted in the pressurised zone while the power module and the brushless drive motor/generator of the starting/generating system are mounted in a non-pressurised zone.

18. The method for starting an aircraft turbine engine by means of a starting/generating system according to claim 10, method wherein: The control module emits starting instructions to the power module via the two-way communication cable so that it powers the brushless drive motor/generator from the on-board electrical network and The control module emits a control signal to the brushless drive motor/generator via the control cable in order to control the torque and/or the drive speed of the brushless drive motor/generator.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The invention will be better understood when reading the following description, given solely by way of example, and in reference to the accompanying drawings wherein:

[0027] FIG. 1 diagrammatically shows a starting/generating system according to the prior art,

[0028] FIG. 2 diagrammatically shows a proposition of a new starting/generating system,

[0029] FIG. 3 diagrammatically shows a starting/generating system according to the invention and

[0030] FIG. 4 diagrammatically shown in detail a starting/generating system according to the invention.

[0031] Note that the figures disclose the invention in a detailed manner to implement the invention, said figures of course can be used to better define the invention where applicable.

DETAILED DESCRIPTION

[0032] In reference to FIG. 3, a starting/generating system for an aircraft turbine engine is shown according to an embodiment of the invention. The starting/generating system comprises a brushless drive motor/generator 1, a control module 6 and a power module 7.

[0033] In reference to FIG. 3, the power module 7 is mounted in a non-pressurised zone NP of the aircraft, adjacent to the brushless drive motor/generator 1. The control module 6 is mounted in a pressurised zone P of the aircraft, at a distance from the power module 7 mounted in a non-pressurised zone NP. The control module 6 is connected to the power module 7 by a two-way communication cable L3 in order to control its operation.

[0034] The invention shall be presented for an aircraft turbine engine, in particular an aircraft turbojet, but it goes without saying that the invention also applies to a helicopter turbine engine.

[0035] The brushless drive motor/generator 1 is configured to start the turbine engine. It comprises in a known manner a stator portion (stator) and a rotor portion (rotor) rotatably mounted with respect to the stator portion. The rotor portion is connected to a shaft of the turbine engine so as to allow for the driving thereof during the starting, the rotor portion being driven by the shaft of the turbine engine during the generating of current following the starting of the turbine engine.

[0036] The power module 7 is connected to an on-board electrical network 4, in particular, a low-voltage electrical network. Preferably, the on-board electrical network 4 is of the 28 VDC type. The power module 7 is configured to supply electrical power to the brushless drive motor/generator 1 during the starting from the electrical power supplied by the on-board electrical network 4. During the starting, the on-board electrical network 4 is electrically powered by an auxiliary source. Following the starting, during the generating, the power module 7 is configured to supply the electrical power to the on-board electrical network 4 from the electrical power supplied by the brushless drive motor/generator 1. In other words, following the starting, the on-board electrical network 4 is electrically powered by the turbine engine.

[0037] As shown in FIG. 4, the power module 7 comprises electronic components so as to electrically power and receive the electrical power from the brushless drive motor/generator 1. In particular, the power module 7 comprises at least one inverter-rectifier 71 which comprises, preferably, a plurality of controllable transistors. In this example, the power module 7 comprises at least one device for measuring 72 one or more of the following parameters of the brushless drive motor/generator 1: direct voltage in interface with the on-board electrical network 4, phase current, control signal, speed of a rotor, angular position of a rotor, temperature.

[0038] Preferably, the power module 7 and the brushless drive motor/generator 1 are separated by less than 10 cm, which limits any loss of power linked to the cabling. Preferably, the power module 7 and the brushless drive motor/generator 1 are connected together directly.

[0039] In reference to FIG. 3, the power module 7 and the brushless drive motor/generator 1 are housed in the same housing 3 in an aircraft nacelle so as to limit the size. Preferably, the housing 3 is metal so as to form a Faraday cage in order to favour electromagnetic confinement.

[0040] Optionally, the starting/generating system further comprises a cooling module 8 as shown in FIGS. 3 and 4. The cooling module 8 advantageously makes it possible to simultaneously cool the power module 7 and the brushless drive motor/generator 1 in a synergistic manner. Advantageously, the size of the cooling module 8 is substantially identical to the prior art and is mounted in the housing 3 of the nacelle. Advantageously, the control module 6 does not need to be cooled, as the starting/generating system comprises only one cooling module.

[0041] The control module 6 is configured to emit a control signal to the brushless drive motor/generator 1 in order to control its operation. In this example, in reference to FIG. 3, the control module 6 is connected to the brushless drive motor/generator 1 by a control cable L1 similar to the prior art. In a known manner, the control signal makes it possible to control the torque and/or the rotation speed of the brushless drive motor/generator 1. In practice, the control module 6 is connected to a calculator the aircraft from which it receives its instructions.

[0042] The control module 6 is also configured to control the operation of the power module 7, in particular, during the starting and during the generating. In the prior art, the control module 6 was mounted directly to the power module 7. According to the invention, the control module 6 is offset from the power module 7 and connected to the latter by a two-way communication cable L3 in order to control its operation. Preferably, the two-way communication cable L3 is of the BUS type and allows for digital communication between the control module 6 and the power module 7. Contrary to a power cable L2 according to the prior art, a two-way digital communication cable L3 induces hardly any electromagnetic disturbances on the control cable L1 (or any power losses). Also, the constraints for connecting the control module 6, located in a pressurised zone P, to the power module 7 and to the brushless drive motor/generator 1, located in a non-pressurised zone P, are eliminated given that the communication cable L3 has no impact on the control signal transmitted by the control cable L1.

[0043] As shown in FIG. 4, the control module 6 comprises a device for generating a control signal 61 configured to emit a control signal on the control cable L1 intended for the brushless drive motor/generator 1. The control module 6 comprises a device for controlling the starting 62, a device for controlling the generating 63 as well as a device for calculating 64 control duty cycles of the transistors of the inverter-rectifier 71 of the power module 7. Thanks to the devices 62, 63, 64, the control module 6 makes it possible to precisely control the power module 7, which is particularly important for a brushless drive motor/generator 1 in comparison with a drive motor/generator with brushes according to the prior art. Preferably, the different functional devices 61-64 of the control module 6 belong to the same electronic card or to several electronic cards. Alternatively, the calculation device 64 is configured to calculate a current setpoint in starting mode associated with a local synchronous rectification.

[0044] Thanks to the two-way communication cable L3, the control module 6 and the power module 7 can exchange data to carry out an optimum starting or generating. For example, the power module 7 can transmit measurements taken by the measuring device 72 so that the calculation device 64 of the control module 6 calculates optimum control duty cycles of the transistors which are transmitted to the inverter-rectifier 71 of the power module 7.

[0045] In this example, the starting/generating system is mounted in an aircraft. The aircraft comprises, on the one hand, a pressurised zone P, in particular an avionics bay 5 housed in the fuselage of the aircraft, and on the other hand, a non-pressurised zone NP, in particular, a turbine engine nacelle. The nacelle of a turbine engine is located in the immediate vicinity of the turbine engine in order to be able to start it. The nacelle comprises the housing 3 wherein the brushless drive motor/generator 1, the power module 7 and the cooling module 8 are mounted. The control module 6 is housed in the avionics bay 5. In this example, the pressurised zone P is an avionics bay 5 and the non-pressurised zone NP is a nacelle but it goes without saying that the zones could be different.

[0046] An example of an implementation of a method for starting shall now be presented. First of all, the control module 6 emits starting instructions to the inverter-rectifier of the power module 7 via the two-way communication cable L3 so that it powers the brushless drive motor/generator 1 from the on-board electrical network 4. The control module 6 also emits a control signal, generated by the generation device 61, to the brushless drive motor/generator 1 via the control cable L1 in order to control the torque and/or the drive speed of a shaft of the turbine engine in order to start it.

[0047] Preferably, the power module 7 takes measurements of parameters of the power module 7 and/or of the brushless drive motor/generator 1 and transmits the parameter or parameters measured to the control module 6 so that the latter adapts the control instructions sent to the inverter-rectifier. Preferably, the calculation device 64 of the control module 6 calculates the optimised control duty cycles of the transistors of the inverter-rectifier 71 from the parameters obtained by the measuring device 72.