DE102017120920A1 - Hybrid powertrain with vibration damping - Google Patents

Abstract

A hybrid powertrain (1) with vibration damping is disclosed. The hybrid powertrain (1) comprises an internal combustion engine (2); a clutch (4), a mechanical damping element (6), an electric motor (8), a transmission (10) and a battery (12) which is electrically connected to the electric motor (8). For vibration damping and an electrical resonant circuit (20) is provided, which comprises at least one capacitor (22) and an inductor (24) and is electrically connected to the electric motor (8) and the battery (12).

Description

The present invention relates to a hybrid powertrain with vibration damping. The hybrid powertrain includes an internal combustion engine and a clutch connected to the engine via a shaft. A mechanical damping element that sits in the shaft connects the clutch to an electric motor. A gear is connected via the shaft to the electric motor. A battery is electrically connected to the electric motor.

The German patent application DE 199 34 936 A1 discloses a powertrain, in particular for motor vehicles, comprising a drive element, such as an internal combustion engine, with a drive shaft, an output element with an input shaft, such as a transmission with transmission input shaft, and at least one electrically connected to the drive train electrical machine. Furthermore, a coupling arranged between the drive shaft and the input shaft of the output element is provided at least in the power flow, which enables coupling and uncoupling operations of the drive element from the output element.

So far, the conventional control of an electric motor in the hybrid powertrain only allows a vibration damping frequency that is too low for most driving conditions. Among other things, limiting factors for this are so far the inductance of the electric motor, the control by the power electronics or the available voltages, which prevent a faster current increase at a given voltage and thus limit the torque response.

An additional complex mechanical damper is required, but often not sufficient due to the space requirement of the electric motor.

It is therefore an object of the present invention to provide a vibration damping for an electric motor in a hybrid powertrain, which takes up little space and thereby does not limit the torque response.

This object is achieved by a hybrid drive train with vibration damping, comprising the features of claim 1.

The hybrid powertrain according to the invention with vibration damping comprises an internal combustion engine and a clutch, which is connected to the internal combustion engine via a shaft. In the shaft from the clutch to an electric motor sits a mechanical damping element. The electric motor is followed by a gearbox, which is connected via the shaft to the electric motor. In addition, a battery (traction battery) is provided, which is electrically connected to the electric motor. With the electric motor, an electrical resonant circuit of at least one capacitance and an inductance is connected. The battery is also electrically connected to the electrical resonant circuit. The electrical resonant circuit is thus connected to the power coupling with the battery and can, depending on the operating mode, remove the energy ("filling mode" moment) or feed ("reduction mode" moment).

There are two possible embodiments for the connection of the electrical oscillating circuit to the electric motor. Thus, on the one hand, the electrical resonant circuit can be arranged parallel to a conventional electric motor. The required components (capacitance and inductance) can also be advantageously arranged outside the space limitations in the hybrid powertrain and thus represent an add-on system. Another possibility is that the electrical resonant circuit is integrated in the electric motor.

According to a possible embodiment of the invention, the capacitance and the inductance of the electrical oscillating circuit of the electric motor are separate components. It is also possible that the inductance of the electrical resonant circuit is at least one winding of the electric motor. Preferably, the capacitance consists of at least one capacitor and the inductance of at least one coil. The capacitance and / or the inductance can be designed to be variable.

The electrical oscillation circuit interacts with the electric machine, i. The coupling of the electrical resonant circuit is done as a superposition of the "normal" control of the electric motor. This results in significantly more design freedom, especially in terms of frequency and voltage, which may possibly be significantly higher than the "normal" control of the electric motor in the electrical circuit. As already mentioned, the resonant circuit consists of a possibly variable capacitive part and a possibly variable inductive part. The inductive part may also be partially or wholly represented by the electric machine (the windings of the electric machine's coils). In the event that a separation of the "normal" and supplied by the resonant circuit windings of the electric motor must be made, it is possible to divide the windings of the electric motor in just these two groups. Thus, a reaction of the coupling of the resonant circuit is not given to the control of the normal turns.

By changing the capacitance or inductance, the natural frequency of the Resonant circuit can be changed. If this adapted frequency is coupled into the electric motor with corresponding power, an appropriate torque change can be introduced into the drive train, which smoothes the resulting torque.

• 1 eine schematische Ansicht eines Hybridantriebsstrangs mit einem elektrischen Schwingkreis zur Schwingungsdämpfung der E-Maschine;
• 2 eine schematische Ansicht eines Hybridantriebsstrangs mit einer anderen Ausführungsform des elektrischen Schwingkreises zur Schwingungsdämpfung der E-Maschine;
• 3 eine Momentenschwankung einer Brennkraftmaschine als Funktion der Zeit;
• 4 eine Momentenschwankung der Brennkraftmaschine mit Schwingungsdämpfung der E-Maschine als Funktion der Zeit („Auffüllmodus“);
• 5 eine Momentenschwankung eines Verbrennungsmotors als Funktion der Zeit;
• 6 eine Momentenschwankung der Brennkraftmaschine mit Schwingungsdämpfung der E-Maschine als Funktion der Zeit („Reduktionsmodus“);
• 7 eine schematische Darstellung einer Anordnung zur Veränderung der Induktivität;
• 8 eine schematische Darstellung einer Schaltung zur Veränderung der Kapazität;
• 9 eine schematische Schnittansicht einer E-Maschine, die die Verwendung der Statorspulen zeigt; und
• 10 eine schematische Schnittansicht einer E-Maschine, die eine andere Verwendungsmöglichkeit der Statorspulen zeigt.

In the following, embodiments of the invention and their advantages with reference to the accompanying figures will be explained in more detail. The proportions in the figures do not always correspond to the actual size ratios, as some shapes are simplified and other shapes are shown enlarged in relation to other elements for ease of illustration. Showing:

• 1 a schematic view of a hybrid powertrain with an electrical resonant circuit for vibration damping of the electric motor;
• 2 a schematic view of a hybrid powertrain with another embodiment of the electrical resonant circuit for vibration damping of the electric motor;
• 3 a torque fluctuation of an internal combustion engine as a function of time;
• 4 a torque fluctuation of the engine with vibration damping of the electric motor as a function of time ("filling mode");
• 5 a torque fluctuation of an internal combustion engine as a function of time;
• 6 a torque fluctuation of the engine with vibration damping of the electric motor as a function of time ("reduction mode");
• 7 a schematic representation of an arrangement for changing the inductance;
• 8th a schematic representation of a circuit for changing the capacity;
• 9 a schematic sectional view of an electric motor, showing the use of the stator coils; and
• 10 a schematic sectional view of an electric motor, showing another use of the stator coils.

For identical or equivalent elements of the invention, identical reference numerals are used. Furthermore, for the sake of clarity, only reference symbols are shown in the individual figures, which are required for the description of the respective figure.

A first possible embodiment of a hybrid powertrain 1 with vibration damping is in 1 shown. The hybrid powertrain 1 owns an internal combustion engine 2 that over a wave 5 with a clutch 4 connected is. A mechanical damping element 6 (Spring damper) sits in the shaft 5 that the clutch 4 with an electric machine 8th combines. A gearbox 10 is about the wave 5 with the electric motor 8th connected. A battery 12 is with the electric machine 8th over a line 9 electrically connected. The battery 12 includes the traction battery, a voltage converter and other electrical components.

wobei L die Induktivität du C die Kapazität sind.At the in 1 shown embodiment is an electrical resonant circuit 20 with the electric motor 8th over a line 21 connected. About a line 26 is the electrical resonant circuit 20 also with the battery 12 connected. The electrical resonant circuit 20 includes a capacity 22 that consists of at least one capacitor 23 exists and an inductance 24 that consists of at least one coil 25 consists. The capacity 22 and the inductance 24 can be designed to be variable. A frequency f _{0 of} the electrical resonant circuit 20 also calculates the following equation: $$f_0=\frac{1}{2\pi \sqrt{LC}}.$$

where L is the inductance du C is the capacitance.

2 shows a further embodiment of the electrical resonant circuit 20 that in the hybrid powertrain 1 Use finds. On the re-description of the structure of the hybrid powertrain 1 is omitted for simplicity, since the hybrid powertrain 1 sufficiently in the description 1 has been described.

At the in 2 The embodiment shown is the capacity 22 of the electrical resonant circuit 20 with the electric motor 8th over the wires 21 connected. About a line 26 is the electrical resonant circuit 20 also with the battery 12 connected. The inductance 24 of the electrical resonant circuit 20 is at least one coil in this embodiment 25 the electric machine 8th , As already in the description too 1 mentioned, includes the capacity 22 at least one capacitor 23 and the inductance 24 is from the windings of at least one coil 25 the electric machine 8th educated. The capacity 22 can be designed to be variable.

3 and 5 show a torque fluctuation 30 an internal combustion engine 2 as a function of time. The torque fluctuation 30 the internal combustion engine 2 fluctuate around an effective mean moment 31 the internal combustion engine 2 ,

4 shows a torque fluctuation 30 the internal combustion engine 2 with vibration damping of the electric motor 8th as a function of time ("refill mode"). Due to the vibration damping with the electric motor 8th become the valleys 32 the torque fluctuation 30 the internal combustion engine 2 through the "refill mode", ie by a positive energy input in the amount of torque amplitudes to be damped 33 , filled up. With the vibration damping of the electric motor 8th you reach an increased effective mean moment 34 compared to the middle moment 31 out 3 ,

6 shows a torque fluctuation 30 the internal combustion engine 2 with vibration damping of the electric motor 8th as a function of time ("reduction mode"). Due to the vibration damping with the electric motor 8th become the mountains 36 the torque fluctuation 30 the internal combustion engine 2 by the "reduction mode Imodus", ie by a negative energy input in the amount of the momentum amplitudes to be damped 33 , taken away. This can be done for example by energy extraction or recuperation. With the vibration damping of the electric motor 8th you reach a reduced effective mean moment 37 compared to the middle moment 31 out 3 ,

7 shows a schematic representation of an arrangement for changing the inductance 24 , The coil 25 can be a core 40 be assigned, for example, consists of a highly permeable material. The inductance 24 can then by moving in the core 40 in the coil 25 increase. The inductance 24 can by moving in the core 40 be reduced. For this the core exists 40 from a good conductive material. By moving in reaches a field displacement.

8th shows a schematic representation of a circuit 50 to change the capacity 22 , The circuit 50 consists of several parallel connected capacitors 23 which can be switched on or off as needed. The capacity 22 This can be changed in stages. A continuous change in capacity 22 can be achieved with a variable capacitor.

9 shows a schematic sectional view of an electric motor 8th that the use of the stator coils 60 shows. The electric machine 8th consists of a stator 61 and a runner 62 For example, the runner may be permanently energized. In the embodiment shown here, all stator coils take 60 on the traction supply and the resonant circuit supply part. 10 shows a schematic sectional view of an electric motor 8th , which is another use of the stator coils 60 shows. Here are some stator coils 63 at the traction supply and some stator coils 64 participate in the resonant circuit supply.

LIST OF REFERENCE NUMBERS

1

Hybrid powertrain

2

Internal combustion engine

4

clutch

5

wave

6

mechanical damping element

8th

E-machine

9

management

10

transmission

12

battery

20

resonant circuit

21

management

22

capacity

23

capacitor

24

inductance

25

Kitchen sink

26

management

30

torque fluctuation

31

middle moment

32

valley

33

moment magnitude

34

increased effective mean moment

36

mountain

37

reduced effective mean moment

40

core

50

circuit

60

stator coils

61

stator

62

runner

63

Stator coils for traction supply

64

Stator coils for resonant circuit supply

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 19934936 A1 [0002]

Claims (4)

A hybrid driveline (1) with vibration damping, comprising: an internal combustion engine (2); a clutch (4) connected to the internal combustion engine (2) via a shaft (5); a mechanical damping element (6) seated in the shaft (5) connecting the clutch (4) to an electric motor (8); a transmission (10) connected to the electric motor via the shaft (5) (8) is connected; and a battery (12) which is electrically connected to the electric machine (8), characterized in that an electrical oscillating circuit (20) comprising at least one capacitor (22) and an inductor (24) is connected to the electric motor (8). Machine (8) and the battery (12) is electrically connected. Hybrid powertrain (1) after Claim 1 , wherein the capacitance (22) and the inductance (24) of the electrical resonant circuit (20) of the electric motor (8) are separate components and the electrical resonant circuit (20) attached to the electric motor (8) or in the E -Machine (8) is integrated. Hybrid powertrain (1) after Claim 1 in which the inductance (24) of the electrical oscillating circuit (20) comprises windings of at least one coil (25) of the electric motor (8) and the electric oscillating circuit (20) is mounted on the electric motor (8) or in the electric motor (8) is integrated. Hybrid drive train (1) according to one of the preceding claims, wherein the capacitance (22) consists of at least one capacitor (23) and the inductance (24) of at least one coil (25) and the capacitance (22) and / or the inductance (24 ) are designed variable.

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