PROPELLER DRIVES AND VEHICLES

Abstract

The disclosure relates to a propeller drive that is, in particular, an aircraft drive and includes a propeller machine and an electric drive connected without a converter to the propeller machine. The aircraft includes such a propeller drive.

Claims

1. A propeller drive comprising: a propeller machine; and an electric drive connected without a converter to the propeller machine.

2. The propeller drive of claim 1, wherein the electric drive has an AC connection, to the propeller machine.

3. The propeller drive of claim 1, wherein the electric drive has an electrical energy source, and a current generator connected thereto.

4. The propeller drive of claim 1, further comprising: an electrical energy store connected to the electric drive.

5. The propeller drive of claim 4, wherein at least two of the electric drive, the propeller machine, and the electrical energy store are connected to one another in a switchable fashion.

6. The propeller drive of claim 1, wherein the propeller machine has at least one propeller with a controllable blade pitch angle, at least one separate open-loop rotational speed controller, at least one closed-loop rotational speed controller, or a combination thereof.

7. The propeller drive of claim 1, wherein the propeller machine and the electric drive have a different number of magnetic pole pairs.

8. The propeller drive of claim 1, wherein the propeller machine has a synchronous machine which is configured such that a tipping point is not reached during operation of the propeller drive.

9. The propeller drive of claim 8, wherein the propeller machine is embodied without a damper winding.

10. The propeller drive of claim 3, further comprising: a cooling circuit, wherein one or more of the electric drive, the propeller machine, the drive motor, or the electric generator is thermally connected to the cooling circuit.

11. A vehicle, comprising: a propeller drive having a propeller machine; and an electric drive connected without a converter to the propeller machine.

12. The vehicle of claim 11, wherein the vehicle is an aircraft.

13. The propeller drive of claim 1, wherein the propeller drive is a vehicle drive.

14. The propeller drive of claim 13, wherein the vehicle drive is an aircraft drive.

15. The propeller drive of claim 2, wherein the AC connection is a three-phase electrical connection.

16. The propeller drive of claim 3, wherein the electrical energy source is a drive motor.

17. The propeller drive of claim 16, wherein the drive motor is an internal combustion engine.

18. The propeller of claim 4, wherein the electrical energy store is connected to the electric drive via a converter.

19. The propeller drive of claim 4, wherein the electric drive, the propeller machine, and the electrical energy store are each connected to one another in a switchable fashion by three-phase switches.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The disclosure will be described in more detail below with reference to an exemplary embodiment which is illustrated in the drawing, in which:

[0019] FIG. 1 depicts a basic schematic diagram of a known aircraft having a propeller drive which corresponds to the prior art.

[0020] FIG. 2 depicts a basic schematic diagram of an aircraft having a propeller drive according to an exemplary embodiment.

DETAILED DESCRIPTION

[0021] The aircraft 10 illustrated in FIG. 1 has an aircraft drive in the form of a propeller drive 20. The design of this propeller drive 20 is known per se and forms part of the prior art.

[0022] The propeller drive 20 includes an internal combustion engine 30 which burns fuel, in the case illustrated aviation fuel, for the purpose of acquiring kinetic energy. The internal combustion engine 30 makes available this kinetic energy in the form of rotational energy by a rotating shaft 40. The rotating shaft 40 is connected to an electric generator 50 that converts the kinetic energy into electrical energy by electromagnetic induction. The electric generator 50 makes available the electrical energy in the form of three-phase current with corresponding power. This three-phase current feeds, via a three-phase line connection 60, an electric converter 70, which converts the three-phase current into a DC intermediate circuit 80. In turn, a converter 90 is connected to this DC intermediate circuit 80, the converter 90 making available a three-phase current with a suitable frequency for driving an electric machine 100, which converts the three-phase current into kinetic energy of a rotating propeller 110.

[0023] In the example illustrated in FIG. 1, the in each case two converters 90 are respectively present on the drive side of the DC intermediate circuit 80, which converters 90 each feed an electric machine 100 in order to drive one propeller 110 each.

[0024] In order to buffer electrical energy, a high-voltage battery 130 is also present in the example shown in FIG. 1, which high-voltage pressure battery 130 is connected to the DC intermediate circuit 80 by a DC connection.

[0025] The aircraft 10 illustrated in FIG. 2 has, on the other hand, an aircraft drive in the form of a propeller drive 20.

[0026] The propeller drive 20 shown in FIG. 2 also has an internal combustion engine 30 that burns fuel in the form of aviation fuel and makes available kinetic energy as rotational energy by a rotating shaft 40. As in the example illustrated in FIG. 1, the rotating shaft 40 is connected to an electric generator 50 that converts the kinetic energy into electrical energy by electromagnetic induction. The electric generator 50 also makes available the electrical energy in the form of three-phase current with a corresponding power level according to FIG. 2.

[0027] However, in contrast to the propeller drive 20 illustrated in FIG. 1, the electric generator 50 according to FIG. 2 is not connected to the electric machine 100 via two converters 70, 90 and an intermediate DC intermediate circuit 80. Instead, the electric generator 50 feeds the electric machine 100 directly, that is to say without a converter, by a three-phase line connection 60. Consequently, the three-phase current generated in the electric generator 50 is fed directly into the electric machine 100, with the result that the three-phase current of the electric generator 50 may be converted into a rotational movement of the propeller 110 directly by the electric machines 100.

[0028] In the exemplary embodiment illustrated in FIG. 2, the propeller drive 20 has two electric machines 100 connected in parallel to the three-phase line connection 60 and are in the form of synchronous machines, each with a propeller 110 connected thereto. Of course, in further exemplary embodiments (not shown separately), a different number of electric machines 100 with propellers 110 respectively connected thereto may be provided. The electric machines 100 are embodied without a damper winding, e.g., a damper winding or a damper cage is not present.

[0029] In order to buffer electrical energy, a high-voltage battery 130 is additionally present in the exemplary embodiment shown in FIG. 2, which high-voltage battery 130 is connected by a converter 70 to the three-phase line connection 60, which connects the electric generator 50 and the electric machines 100 to one another. For this purpose, the converter 70 converts the three-phase current into a DC circuit 120 in order to charge the high-voltage battery 130.

[0030] On the one hand, the high-voltage battery 130 may be decoupled from the rest of the propeller drive 20 by an electric switch 140 if the high-voltage battery 130 is not necessary to operate the propeller drive 20. For example, the high-voltage battery 130 is connected to the rest of the propeller drive 20 only when energy is actually to be fed from the high-voltage battery 130 or into the high-voltage battery 130.

[0031] In addition, the drive motor 30, together with the shaft 40 and the electric generator 50 may be decoupled from the rest of the propeller drive 20 by a further electric switch 140. In addition, by a further electric switch 140, the electric machines 100 may be decoupled, together with the propellers 110 connected thereto, from the rest of the propeller drive 20. In particular, damaging parts of the propeller drive 20 may, if appropriate, also be decoupled by the electric switches 140.

[0032] In the illustrated exemplary embodiment, the electric switches 140 may be embodied as mechanical switches for high power levels, specifically as contactors of the type of three-phase switches. Basically, in further exemplary embodiments (not illustrated separately) the electric switches 140 may also be implemented in some other way.

[0033] In the exemplary embodiment illustrated in FIG. 2, a common cooling circuit 150 is additionally provided for cooling the internal combustion engine 30 and the electric generator 50. The cooling circuit 150 is a cooling water circuit.

[0034] Although the disclosure has been illustrated and described in detail by the exemplary embodiments, the disclosure is not restricted by the disclosed examples and the person skilled in the art may derive other variations from this without departing from the scope of protection of the disclosure. It is therefore intended that the foregoing description be regarded as illustrative rather than limiting, and that it be understood that all equivalents and/or combinations of embodiments are intended to be included in this description.

[0035] It is to be understood that the elements and features recited in the appended claims may be combined in different ways to produce new claims that likewise fall within the scope of the present disclosure. Thus, whereas the dependent claims appended below depend from only a single independent or dependent claim, it is to be understood that these dependent claims may, alternatively, be made to depend in the alternative from any preceding or following claim, whether independent or dependent, and that such new combinations are to be understood as forming a part of the present specification.