AT512851B1 - Range extender for a motor vehicle - Google Patents

Abstract

The invention relates to a range extender (1) for a motor vehicle, in particular an electric motor vehicle, comprising: - a first internal combustion engine (2); and a second internal combustion engine (3); - An electromechanical energy converter (4), which is arranged between the first and the second internal combustion engine (2,3); wherein the first internal combustion engine (2), the second internal combustion engine (3) and the electromechanical energy converter (4) are coupled for power transmission.

Description

Description: The present invention relates to a range extender for a motor vehicle, in particular an electric motor vehicle, which has an internal combustion engine and an electromechanical energy converter.

As a range extender refers to additional units in an electric motor vehicle, which usually consist of an internal combustion engine which drives a generator to supply an energy storage device or an electric motor with electrical energy.

Electric motor vehicles are electric motor driven vehicles. Accumulators or batteries are usually used as energy storage device for their energy supply, which can be charged locally via the public power grid or mobile via a range extender or solar modules.

In electric vehicles with a range extender, the internal combustion engine of the range extender is usually started while driving without immediate action of the driver, in particular depending on the state of charge of the energy storage device and turned off. Electrical energy is usually generated by means of an electromechanical energy converter, i. an electric machine, which is usually a permanent magnet synchronous machine. The electromechanical energy converter usually has at least two operating modes, which are controlled by the corresponding control electronics. The generator mode is the normal operation of the range extender. Conversely, this can also be operated in the motor mode. This engine mode is commonly used to start the internal combustion engine.

The range extender should be possible vibration-free operation to ensure maximum smoothness of the electric vehicle. The driving feel of the electric vehicle, which is essentially connected to the lack of an internal combustion engine in the drive train and the associated avoidance of noise and vibration should not be disturbed by the internal combustion engine of the range extender.

From AT 505 950 a power generator for range expansion of an electric vehicle is known, in which the imbalance of the eccentric drive shaft of an internal combustion engine unit by a built-in rotor of the generator first balancing mass and by a rotatably connected to the drive shaft in the region of a second end second balancing mass is compensated.

A reduction in the vibrations of the range extender can also be achieved by arranging on the shaft of the internal combustion engine on both sides of the internal combustion engine electromechanical energy converters, which are corrugated, that is, have the same shaft as the internal combustion engine. Furthermore, it can also be provided here that a first balancing mass is arranged on the rotor of the first electromechanical energy converter and a second balancing mass on the rotor of the second electromechanical energy converter, wherein advantageously at least one of the two balancing masses is formed integrally with the respective rotor.

Also, transverse forces, which are caused by a deflection of the shaft, are avoided in this way, since the shaft is supported on both sides by the electromechanical energy converters.

As shown in the system according to AT 505 950, the shaft is guided to each side of the internal combustion engine on a bearing, which is arranged laterally on the internal combustion engine. Due to the rotor mass of the electromechanical energy converter, however, the shaft bends through, since the electromechanical energy converter is usually free-floating in order to avoid over-determination of the shaft bearing. An increase in performance in the generator mode of this type of range extender is therefore limited possible because new imbalances are introduced into the system via the deflection of the shaft.

Furthermore, caused by the deflection of the shaft shear forces acting on the bearings.

The present invention has for its object to provide an improved range extender, which reduces the above problems.

The object is solved by the teaching of the independent claims, Advantageous embodiments of the invention are claimed in the dependent claims.

The range extender according to the invention comprises an electromechanical energy converter, which is arranged between a first and a second internal combustion engine, wherein the first internal combustion engine, the second internal combustion engine and the electromechanical are coupled for power transmission.

An electromechanical energy converter according to the invention is used for the conversion of electrical energy into mechanical energy and vice versa. These include in particular electric motors and electric generators. Depending on the direction of the transmitted power is between the electromechanical energy converter between engine operation, while power is transmitted from the electrical side to the mechanical side and a generator operation with reverse power flow distinguished.

Under an internal combustion engine in the context of the invention heat engines are to be understood, which convert chemical energy of a fuel into mechanical energy via a combustion process. In the operation of an internal combustion engine is usually displaced by the expansion of an air fuel mixture during combustion in a working chamber usually referred to as a piston drive element from the combustion chamber, whereby this drives a drive shaft in motion, preferably in rotation.

A motor vehicle according to the invention is a mobile means of transport, which serves the transport of goods, tools or people and is driven by machine.

Under an electric motor vehicle according to the invention is preferably a motor vehicle to understand, which is powered by electrical energy from an energy storage device, preferably an electrochemical energy storage, a battery or a battery. If the accumulator or the battery is emptied, it must be recharged, either via the mains or a mobile supply device, preferably a range extender or solar cells. The integration of the electromechanical energy converter between two internal combustion engines has the advantage that the rotor mass of the electromechanical energy converter is now distributed over two bearings, since the shaft is mounted on both sides of the electromechanical energy converter to the internal combustion engines. The deflection of the shaft of the rotor of the electromechanical energy converter can be almost eliminated in this way, resulting in a higher smoothness of the range extender.

In an advantageous embodiment of the invention, the first internal combustion engine and the second internal combustion engine are a first disc and a second disc of a rotary piston machine.

Under rotary piston machine in the context of the invention is preferably to understand a device in which a preferably substantially triangular piston or rotor during operation of the internal combustion engine in the housing performs a rotation about a major axis, wherein the piston about its own axis turns, but which also moves on a preferred own circular path. In other words, the piston exerts a planetary motion about the major axis. An advantage of the use of a rotary piston machine as an internal combustion engine is a higher smoothness of such a machine in comparison with a reciprocating engine. In a preferred embodiment, such a rotary piston engine is a Wankel engine. The invention can also be applied to

Rotary piston machines are used with two, three or more juxtaposed discs. Furthermore, the invention can also be used with any other type of internal combustion engine, preferably a reciprocating engine.

The rotary piston machine has in a particularly advantageous manner in operation on a high smoothness, so that the occupants of a motor vehicle are not disturbed by vibrations. Furthermore, the rotary piston machine compared to a conventional gasoline or diesel engine on a significant low noise. Finally, much higher speeds can be achieved than with a reciprocating engine.

In further advantageous embodiments of the invention, the first and the second disc of the rotary piston machine are arranged substantially symmetrically or asymmetrically with respect to a center plane of the electromechanical energy converter.

In a further advantageous embodiment of the invention, the rotor of the first disc and the rotor of the second disc of the rotary piston machine have the same rotational position with respect to each other. According to a further advantageous embodiment, however, they may also have essentially a rotational position with respect to one another which is essentially 10 to 180 °, preferably 45 °, more preferably 90 ° and particularly preferably 180 °, with the coupling being the axis of rotation.

Due to the different arrangement of the Trochoids of the individual discs of the rotary piston machine and the different rotational position of the rotors of the rotary piston machine to each other, depending on the design of the range extender, a mass balance can be achieved. Therefore, preferably no additional mass balance by balancing weights on the shaft is necessary. Further, also depending on the configuration of the range extender, by the different arrangement of these elements increased smoothness and a uniform torque curve can be achieved.

In a further advantageous embodiment of the invention, the spark plugs of the first internal combustion engine and the spark plugs of the second internal combustion engine are arranged in such a way that the ignition stroke takes place simultaneously.

This can be achieved that the two internal combustion engines run absolutely synchronously and are not generated by a different timing oscillations.

In a further advantageous embodiment of the invention, the spark plug of the first internal combustion engine and the spark plug of the second internal combustion engine is arranged in such a manner that the ignition timing is offset in time.

By the timing of the ignition strokes a more uniform torque curve of the range extender can be achieved because the particularly high torque is not carried out by the ignition in both internal combustion engines in the same cycle, but in two staggered clocks, that is, in the four cycles, which pass through the two internal combustion engines, preferably two times ignited at different times.

The above and other advantages, features and applications of the present invention will become apparent from the following description of a preferred embodiment with reference to the drawings.

FIG. 1 shows a schematic representation of a range extender according to an embodiment of the invention. [0029] FIG.

Referring to Figure 1, an embodiment of the invention will be explained in more detail. The invention is described using the example of a range extender 1 with a rotary piston machine with substantially triangular rotary piston or rotors. The disks 2, 3 of the rotary piston machine each form a first and a second internal combustion engine and are shown in the figure 1 in such a way that the discs 2, 3 are respectively rotated in the image plane, whereby both the triangular shape of the rotors 6, 7, as well as the Trochoidenform the discs 2, 3 is visible.

The range extender 1 comprises a first disc 2 of a rotary piston machine and a second disc 3 of a rotary piston machine, which are corrugated, i.e., whose rotors 6, 7 are connected to the same shaft 5. The rotors 6, 7 thereby move like a planet around the shaft housing. The shaft 5 connects both discs 2, 3. Between the two discs 2, 3 of the rotary piston machine, the rotor 10 of an electromechanical energy converter is arranged on the shaft 5. To this rotor 10 of the electromechanical energy converter 4, a stator 9a, 9b of the electromechanical energy converter 4 is arranged.

The electromechanical energy converter 4 is a permanent magnet synchronous machine, preferably an internal pole machine, more preferably an external pole machine, more preferably an asynchronous machine, and most preferably a reluctance machine.

The electromechanical energy converter 4 is electrically connected to a power electronics 11, which serves to control the electromechanical energy converter 4 and optionally convert the AC or three-phase current which is generated by this, into direct current, so that this in a circuit, Preferably, a Gleichstromzwi-schenkreis, can be fed. Conversely, this can be supplied via the rectifier of the power electronics in the motor mode with electrical energy.

FIG. 1 shows a symmetrical arrangement of the trochoidal disks 2, 3 with respect to a center plane M of the electromechanical energy converter 4. In particular, the trochoids are aligned the same. Also, the distance of the discs 2, 3 from the median plane M is shown the same. However, it could also be provided that the discs 2, 3 are arranged asymmetrically. Preferably, the trochoids of the discs 2, 3 could be aligned asymmetrically and the distance from the center of life M of the two discs 2, 3 could be different.

The rotational position of the rotors 6, 7 of the discs 2, 3 of the rotary piston machine are shown offset in the figure 1 by 180 °. However, the rotational position could also be offset only by 90 ° or 45 ° or at any angle 10 to 180 °. Furthermore, the rotors 6, 7 could also be arranged symmetrically to the center plane M of the first electromechanical energy converter 4, that is, have the same rotational position.

The spark plug 8a of the first disc 2 and the spark plug 8b of the second disc 3 of the rotary piston engine are arranged in the figure 1 in such a way that the ignition timing of the two discs 2, 3 of the rotary piston machine takes place simultaneously. It could, however, preferably also be provided that these are arranged such that the ignition cycle takes place offset in time.

In the generator mode, the two disks 2, 3 of the rotary piston machine drive the electromechanical energy converter 4, so that this generates electrical energy as a generator. In the motor mode of the electromechanical energy converter 4, this starts the two disks 2, 3 of the rotary piston machine simultaneously. Preferably, however, the electromechanical energy converter can only start a disk 2, which then drives the range extender alone.

Range extender according to the invention can also be used in houses as a combined heat and power plant or as generator units in other mobile applications. LIST OF REFERENCE NUMBERS:

Range extender 1

First internal combustion engine 2

Second internal combustion engine 3

Electromechanical energy converter 4

Wave 5

Rotor of the first internal combustion engine 6

Rotor of the second internal combustion engine 7 spark plug 8a, 8b

Stator of the electromechanical energy converter 9a, 9b

Rotor of the electromechanical energy converter 10

Power electronics 11

Claims (10)

claims 1. Range extender (1) for a motor vehicle, in particular an electric vehicle, comprising: a first internal combustion engine (2); a second internal combustion engine (3) and an electromechanical energy converter (4), which is arranged between the first and the second internal combustion engine (2, 3), characterized in that the first internal combustion engine (2), the second internal combustion engine (3) and the electromechanical Energy converter (4) are coupled for power transmission. 2. range extender (1) according to claim 1, wherein the first internal combustion engine (2) and the second internal combustion engine (3) are a first disc and a second disc of a rotary piston machine. 3. range extender (1) according to claim 1 or 2, wherein the coupling by a common shaft (5). 4. range extender (1) according to claim 2 or 3, wherein the first and the second disc of the rotary piston machine (2, 3) are arranged substantially symmetrically or exactly symmetrical to each other with respect to a median plane (M) of the electromechanical energy converter (4). 5. range extender (1) according to one of claims 2 to 4, wherein the first and the second disc (2, 3) of the rotary piston machine are arranged asymmetrically with respect to a center plane (M) of the electromechanical energy converter (4). 6. range extender (1) according to one of claims 2 to 5, wherein the rotor (6) of the first disc (2) and the rotor (7) of the second disc (3) of the rotary piston machine have the same rotational position with respect to each other, wherein the coupling (5) is the axis of rotation. 7. range extender (1) according to one of claims 2 to 6, wherein the rotor (6) of the first disc (2) and the rotor (7) of the second disc (3) of the rotary piston machine is a substantially 1 to 180 °, Preferably, 4.5 °, more preferably 90 ° and more preferably 180 ° offset rotational position with respect to each other, wherein the coupling (5) is the axis of rotation. 8. range extender (1) according to any one of claims 2 to 7, wherein the spark plug (8a) of the first internal combustion engine (2) and the spark plug (8b) of the second internal combustion engine (3) are arranged in such a way that the ignition timing simultaneously he follows. 9. range extender (1) according to one of claims 2 to 7, wherein the spark plug (8a) of the first internal combustion engine (2) and the spark plug (8b) of the second internal combustion engine (3) are arranged in such a way that the ignition timing is offset in time , 10. Motor vehicle, in particular an electric motor vehicle with a range extender according to one of claims 1 to 9. For this purpose 1 sheet drawings