DE102015203137A1 - Motor vehicle with at least two power generators for generating drive power and method for operating such a motor vehicle - Google Patents

Abstract

The invention relates to a motor vehicle (1) having at least two power generators (3, 5) arranged to generate drive power, each power generator (3, 5) comprising at least one electric machine (3.2, 5.2) and a high-voltage circuit (7, 9). having. It is provided that the high-voltage circuits (7, 9) of the at least two power generators (3, 5) are electrically connected to each other.

Description

The invention relates to a motor vehicle with at least two power generators for generating drive power, and to a method for operating such a motor vehicle.

Motor vehicles with at least two power generators, which are each set up to generate drive power, are known in principle. In particular, rail vehicles exist which are designed as railcars or power cars, which have two power generators. Each power generator has at least one electric machine which is operable as a generator - in particular driven by an internal combustion engine or by deceleration power of the motor vehicle in a so-called recuperation mode - and / or as an electric motor for generating drive power for the motor vehicle. At least one of the power generators has an internal combustion engine that is operatively connected to the electric machine of the power generator. In particular, hybrid systems are also possible in which an internal combustion engine is assigned more than one electrical machine, as is known, for example, in the passenger car model Prius from Toyota. Each power generator has an associated high-voltage circuit to which the at least one electric machine of the power generator is electrically connected. In known motor vehicles, the various high-voltage circuits of the power generator are separated, so provided separately from each other. A vehicle electrical system supply of the motor vehicle is typically not via one of the high-voltage circuits, but rather via a low-voltage circuit, in particular via a 24 volt DC circuit. This is typically powered by lead-acid batteries, it being possible for them to be charged by at least one of the high-voltage circuits. If one of the lead acid batteries fails, the onboard power supply is at risk. Starters for the power plant's internal combustion engines are also typically supplied with electrical power from the lead-acid batteries, which places a heavy burden on the lead-acid batteries and the starter circuit, with acceptable starting conditions for the internal combustion engines.

The invention has for its object to provide a motor vehicle and a method for operating such a motor vehicle, said disadvantages do not occur.

The object is achieved by providing the subject matters of the independent claims. Advantageous embodiments emerge from the subclaims.

The object is achieved in particular by providing a motor vehicle with at least two power generators set up for generating drive power, wherein each power generator has at least one electrical machine and one high-voltage circuit. The motor vehicle is characterized in that the high-voltage circuits of the at least two power generators are electrically connected to each other. This results in advantages over the prior art. In particular, it is possible due to the higher availability of the combined high-voltage circuits to feed the vehicle electrical system directly from the high-voltage circuits. In particular, the on-board power supply can be connected to high-voltage lithium batteries of the high-voltage circuits. Lead batteries can then be omitted, or at least their number and / or size can be reduced. At the same time, at least if at least one of the power generator has an internal combustion engine, a higher availability for the electrical system supply and in particular a higher reliability, because the failure of a high-voltage lithium battery tolerated and in particular by one of the high-voltage circuits, not from the Battery failure is affected, can be compensated. Even with a total failure of the high-voltage batteries, the electrical system supply is ensured because at least one electric machine of the power generator - in particular driven by an internal combustion engine - can be operated in generator mode and generate electrical power for the electrical system supply. This also increases the fault tolerance of the vehicle electrical system. At the same time, the availability and fault tolerance of the high-voltage circuits increases, since a failure in a high-voltage circuit of a power generator can be compensated by the other power generator and its high-voltage circuit. Starters of internal combustion engines of the power generator can now be fed directly from the combined high-voltage circuits, resulting in a lower load on components and improved starting behavior of the internal combustion engine. In general, the starting power can be provided by various sources.

Preferably, at least one of the power generators has an internal combustion engine, which is operatively connected to the electrical machine of the power generator, in particular to drive them in a generator operation. Vorzgsweise the electric machine is additionally or alternatively operable as an electric motor.

The term "power generator" is understood here and below to mean a machine or an aggregate of machines which is set up to generate drive power for a machine Motor vehicle. A "power generator" is thus in this sense a "drive power generator".

It is possible that one of the power generators is designed as a diesel-electric drive. Such a diesel-electric drive preferably has an electric machine and an internal combustion engine, in particular a diesel engine, wherein the electric machine is driven by the internal combustion engine as a generator and generates electrical power. The diesel-electric drive preferably has a second electric machine, by means of which electrical power generated by the first electric machine can be converted into mechanical power, and thus into drive power. Thus, while the first electric machine is operated as a generator, the second electric machine is operated as a motor. If, in addition, an energy store for electrical energy, in particular a battery or an accumulator, is provided, such a diesel-electric drive can also be regarded as a serial hybrid drive.

Particularly preferred is also an embodiment in which at least one of the power generator is designed as a hybrid power generator. Such a hybrid power generator is preferably characterized by a combination of an internal combustion engine with an electric machine, which can be operated as a motor or as a generator, in particular, depending on operating point. It is possible for such a hybrid power generator to have more than one electrical machine, for example two electric machines which-in particular operating point-dependent-can be operated as a motor and / or as a generator. Furthermore, the hybrid power generator is preferably assigned an electrical energy store, in particular a battery or an accumulator. A hybrid power generator can be designed as a serial hybrid drive, as a parallel hybrid drive or as a mixed hybrid drive.

Furthermore, it is possible for at least one of the power generators to be embodied as a purely electrical drive, preferably with exactly one electrical machine that can be operated as a motor.

Also preferred is a combination of a diesel-electric or hybrid drive as the first power generator with a purely electric drive as the second power generator, or the combination of a diesel-electric drive as the first power generator with a hybrid drive as the second power generator.

Each of the power generators of the motor vehicle preferably has at least one internal combustion engine, wherein each internal combustion engine is preferably assigned at least one electrical machine, which is preferably operable as a generator and / or as an electric motor. In that regard, the power generators are preferably designed in particular as diesel-electric drives or as hybrid drives. It is possible that both power generators are of identical design, ie both as diesel-electric drives or both as hybrid drives.

Specifically, in particular a first embodiment is preferred, in which a first power generator is designed as a diesel-electric drive, wherein a second power generator is designed as a purely electric drive. The drives connected to one another via the electrical connection of the high-voltage circuits can be considered as a serial hybrid drive for the motor vehicle as a whole.

Specifically, a second embodiment is preferred in which a first power generator is designed as a hybrid drive, wherein a second power generator is designed as a hybrid drive. The electrically interconnected drives can be considered in total as a parallel hybrid drive for the motor vehicle.

Specifically, a third embodiment is preferred, in which a first power generator is designed as a hybrid drive, wherein a second power generator is designed as a purely electric drive. The power generators electrically connected to each other can be considered as a mixed hybrid drive for the motor vehicle.

The term "battery" is generally addressed here an electrical storage device. It may be a battery in the strict sense and / or an accumulator. Particularly preferably, the battery is designed to be capable of charging, so that it can be charged with electrical energy on the one hand and discharged on the other hand to provide electrical energy.

An embodiment of the motor vehicle is preferred, which is characterized in that the high-voltage circuits of the power generator via an intermediate circuit, in particular via a DC intermediate circuit, are interconnected. The latter is particularly advantageous because the DC link can be connected directly to high-voltage batteries of the high-voltage circuits. Furthermore, there is no need for an inverter between the high-voltage batteries or the high-voltage circuits of the power generator and the DC link. The high-voltage circuits of the power generator are preferably also designed as DC high-voltage circuits.

An embodiment of the motor vehicle is preferred, which is characterized in that an electrical system of the motor vehicle is connected to one of the high-voltage circuits and / or to the intermediate circuit. As already explained above, in this case lead batteries can be saved or even completely eliminated. Rather, it is possible to feed the electrical system directly by the power generator, in particular their electrical machines, and / or from the high-voltage batteries of the high-voltage circuits. This increases - as already explained - the availability, reliability and fault tolerance of the on-board power supply.

An embodiment of the motor vehicle is also preferred, which is characterized in that the motor vehicle is designed as a rail vehicle, in particular as a railcar, as a railcar or as a power car. In particular, in this area, there are corresponding motor vehicles with multi-engine systems, which have a plurality of particular diesel-electric, hybrid or purely electric power generator. Such rail vehicles typically have two car parts, each car part being associated with a power generator. In particular, each carriage part preferably has a drive bogie, wherein each drive bogie is associated with a power generator. Therefore, realize the benefits of the motor vehicle in a special way here. It is possible that the motor vehicle has exactly a railcar, a railcar or a power car. This is also called single traction. But it is also possible that the motor vehicle has a combination of at least two railcars, railcars or power cars. This embodiment is referred to as multiple traction. In this case, several partial motor vehicles are combined to form a motor vehicle, which then applies drive power, for example for driving a train, overall by means of the various partial motor vehicles. In this case, at least one of the partial motor vehicles preferably has at least two power generators which are electrically connected to one another. The other partial motor vehicles preferably also have at least one power generator with a high-voltage circuit, the high-voltage circuits of the partial motor vehicles being connected to form a complete circuit of the motor vehicle. In particular, an intermediate circuit, in particular a DC intermediate circuit, is preferably realized for the entire motor vehicle on a cross-motor vehicle basis. An availability, reliability and fault tolerance of the electrical supply of the motor vehicle is thus increased in a particularly efficient manner, since a large number of power generators is available, so that in particular the failure of a power generator can be compensated for very easily.

However, the basic idea of the invention is also applicable to motor vehicles which are not designed as rail vehicles, for example in ships, larger commercial vehicles, defense vehicles, or other motor vehicles.

The internal combustion engine of at least one of the power generator is preferably designed as a reciprocating engine. It is preferably designed as a diesel engine, as a gasoline engine, as a gas engine for operation with natural gas, biogas, special gas or other suitable gas. However, an embodiment of the internal combustion engine as a diesel engine is particularly preferred.

The object is also achieved by providing a method of operating a motor vehicle, wherein a motor vehicle is operated with at least two power generators for generating drive power, wherein each power generator has at least one electric machine and one high-voltage circuit, and wherein the high-voltage Circuits of the at least two power generators are electrically connected to each other. Within the scope of the method, a motor vehicle is particularly preferably operated according to one of the exemplary embodiments described above. In this case, electrical power or energy is preferably shifted via a formed by the electrical connection of the high-voltage circuits intermediate circuit in dependence on at least one parameter of the power generator and / or the motor vehicle between the power generators or distributed to the power generator. In particular, the advantages which have already been explained in connection with the motor vehicle are realized. In addition, it can be seen that a very flexible power distribution over the DC link to the power generators becomes possible, which not only results in increased availability and better failure safety and fault tolerance. Rather, lifetimes of high-voltage batteries can be increased and maintenance intervals optimized and / or synchronized by carrying out a load distribution in a suitable manner. In particular, a load on the individual high-voltage batteries can be controlled, so that they are loaded homogeneously and thus experience the most uniform possible aging. In particular, a material-friendly operation is possible. Peak currents can be compensated for charging and / or discharging by distributing power to a plurality of high-voltage batteries. Also, the age of high-voltage batteries, which may differ in particular after an exchange of a high-voltage battery in the motor vehicle, can be taken into account. Thus, it is possible, for example, to burden older high-voltage batteries to a lesser extent and to allocate them, in particular, lower peak currents than, for example, newer high-voltage batteries. electrical Power can therefore be distributed or shifted as needed across the limits of the high-voltage circuits of the individual power generator, in order to realize a very efficient control and a material-saving operation of the motor vehicle.

It turns out that the at least one parameter is preferably selected from a group consisting of an operating state of the motor vehicle, a current in the intermediate circuit, an aging state of the power generator, an aging state of high-voltage batteries of the power generator, and a current state of charge of the high-voltage batteries ,

A distribution of the electrical power as a function of an operating state of the motor vehicle is responsive, for example, to recuperation, ie recovery of deceleration energy into electrical energy, which may be sufficient for recuperation due to the specific driving conditions of the motor vehicle, a single power generator, the then recovered electrical Power is supplied not only the high-voltage batteries of the just recuperating power generator, but is also forwarded to high-voltage batteries of other power generator. This reduces the charging current in the recuperating power generator, so that a material-sparing operation in particular of the high-voltage batteries of the power generator is possible. In an analogous manner, the distribution of electrical power can be made dependent on a current in the intermediate circuit. So it is quite possible, for example, at low current, to remove the electrical power only from a high-voltage battery of a power generator or supply this. At higher current intensity, the electrical power is preferably divided among a plurality of high-voltage batteries, in particular a plurality of power generators. Thus, peak currents can be lowered, in particular when charging or discharging the high-voltage batteries, whereby these are spared.

It is also possible for a power generator to be operated purely as a generator for the provision of electrical power for itself and at least one further power generator. It is then possible, for example, to drive a motor vehicle with two power generators purely electrically, wherein only one of the two power generators provides the electric power for the drive combustion engine. In particular, in operating conditions in which otherwise both internal combustion engines of the power generator would have to be operated at partial load, so an increase in the load point of one, solely operated internal combustion engine of the regenerative power generator can be achieved, so that a map-optimized operation is possible there. This is the case, in particular, in the case of a steady movement, in which a speed once achieved is maintained in a rail vehicle. Here typically only 50% of the installed power is needed.

In general, it is possible to operate the internal combustion engine by the possibility of power shift over the intermediate circuit optimized map. In this case, the output by the internal combustion engine power does not necessarily follow a drive setpoint, but it is particularly possible to deliver excess power through the DC link to other power generators and in particular their high-voltage batteries.

As already explained above, an aging state of the high-voltage batteries of the power generator can be taken into account, it being possible in particular to preserve older high-voltage batteries and charge more for newer high-voltage batteries. However, the aging of the high-voltage batteries can also be homogenized and homogenized, which makes it possible in particular not only to extend maintenance intervals, but also to optimize and synchronize.

The electric power can also be distributed depending on a state of aging of the power generator itself, so it is particularly possible to relieve older power generator and correspondingly more burden on newer power generator. This can lead to a gentler operation, in particular of the older power generator, whereby they may have an increased lifetime.

Also, the current state of charge of the high-voltage batteries can be taken into account in the distribution of electrical power. In this case, for example, for an electromotive operation of an electric machine of a power generator whose high-voltage batteries themselves have a low state of charge, electrical power from high-voltage batteries of another power generator or regeneratively generated electrical power of another power generator can be used, which possibly even an electric motor operation the affected power generator is possible, or whereby its high-voltage battery is spared because its state of charge does not need to be further reduced. Conversely, it is also possible to distribute excess electrical power in a high-voltage circuit of a power generator, which can not be stored there due to high states of charge of its high-voltage batteries on high-voltage circuits of other power producers, which then record this electrical power and in their can store respective high-voltage batteries. Thus, it is preferably not necessary to dissipate electrical power in the form of heat because it can not currently be picked up by high voltage batteries.

An embodiment of the method is also preferred, which is characterized in that predetermined charging and / or discharging cycles for high-voltage batteries of the power generator are carried out via the intermediate circuit, electrical energy being shifted via the intermediate circuit between high-voltage batteries of the various power generators. This makes it possible, in particular at predetermined time intervals, to perform suitable charging / discharging cycles for the high-voltage batteries in order to increase their service life. In particular, it is possible to fully discharge a high-voltage battery and then completely recharge. The electrical energy of the high-voltage battery can be readily distributed over the intermediate circuit to other high-voltage batteries and / or power generator, with the necessary for charging electrical energy can be removed in turn from the high-voltage circuits of different power generator. Due to the ability to move electrical energy from a high-voltage circuit of a power generator to other high-voltage circuits of other power producers, so there is the option to drive life-boosting charge / discharge cycles for the high-voltage batteries and thus increase their reliability and their lifetime to extend. Overall, the life cycle costs for the high-voltage batteries are thus reduced.

Preferably, it is also possible to connect the DC link to an external electrical connection. The external connection can also be used to run life-increasing charge / discharge cycles for the high-voltage batteries so that they can be maintained and their service life can be increased. The external connection may be, for example, a depot or shore connection.

Finally, an embodiment of the method is preferred, which is characterized in that in an operating state of the motor vehicle, a first power generator generates combustion engine power and electric power, wherein a second power generator from the first power generator generated electrical power for purely electrical supply of drive power is supplied. It is therefore provided in particular that a first power generator by means of an internal combustion engine on the one hand drive power and on the other hand - via an electric motor driven by the internal combustion engine in the generator mode - generates electrical power. A second power generator is operated in such a way that an internal combustion engine assigned to it does not generate drive power, it being possible for the internal combustion engine to be idling or to be completely switched off. Alternatively, it is also possible that the internal combustion engine drives an electric machine for power generation, but it does not apply drive power for the motor vehicle. The second power generator is supplied via the intermediate circuit electrical power which is at least partially, preferably completely generated by the first power generator, said electric power is converted by an electric machine of the second power generator in driving power. This electrical machine of the second power generator is operated in this respect as an electric motor, however, the electric power is supplied in particular via the DC link from the first power generator. For example, it is possible that a slow travel of the motor vehicle, for example, a journey of a rail vehicle in a car wash, by purely electric drive of a power generator, and by diesel-electric drive of another power generator is implemented. In any case, a more favorable load point for the internal combustion engine of the first power generator can be realized in this way, as would be the case if drive power were additionally applied by the internal combustion engine of the second power generator. In fact, both internal combustion engines would possibly be driven in an unfavorable partial load operation, while it is thus possible to raise the load point of the internal combustion engine of the first power generator which alone applies the drive power and thus to shift it into a region which is more favorable in terms of fuel consumption and pollutant emissions.

It is particularly possible that in a first car part of a rail vehicle, a diesel engine and an electric motor are operated, wherein in a second car part energy from a high-voltage battery of this car part and a high-voltage battery of the first car part, and / or electrical energy from the electric motor the first car part is used. If, for example, an internal combustion engine fails in the second car part, the drive bogie of the second car part can still be driven, namely by the electrical energy provided in the first car part.

Furthermore, as already explained above, it is possible to carry out a load management for the various drive bogies, in particular as a function of a time between the service intervals (TBO - Time Between Overhaul) or according to a drive bogie.

It also shows that the internal combustion engine and electric machine of a hybrid power generator can be used in parallel. A power control does not necessarily have to follow a drive setpoint. Rather, it is possible to charge traction batteries or electrical system batteries, and in particular high-voltage batteries of the high-voltage circuits of the power generator via the drives of the various car parts, and thus on the various hybrid power generators coupled together via the intermediate circuit.

The description of the motor vehicle on the one hand and the method on the other hand are to be understood as complementary to each other. Features of the motor vehicle that have been explicitly or implicitly explained in connection with the method are preferably individually or combined with each other features of a preferred embodiment of the motor vehicle. Method steps which have been explained explicitly or implicitly in connection with the motor vehicle are preferably individually or combined with one another Steps of a preferred embodiment of the method. This is preferably characterized by at least one method step, which is due to at least one feature of the motor vehicle. The motor vehicle is preferably characterized by at least one feature, which is due to at least one method step of a preferred embodiment of the method.

The invention will be explained in more detail below with reference to the drawing. Show

1 shows a schematic representation of a first embodiment of a motor vehicle;

2 a schematic representation of a second embodiment of a motor vehicle;

3 a schematic representation of a third embodiment of a motor vehicle, and

4 a schematic representation of a fourth embodiment of a motor vehicle.

1 shows a schematic representation of an embodiment of a motor vehicle 1 which two power generators 3 . 5 which exemplifies here as a hybrid power generator 3 . 5 are formed. Each of the power producers 3 . 5 is in each case a high-voltage circuit 7 . 9 assigned. Here are the high-voltage circuits 7 . 9 here via a DC link 11 electrically connected to each other. At the DC link 11 it is preferably a DC intermediate circuit.

Each of the power producers 3 . 5 preferably has an internal combustion engine, namely the first power generator 3 an internal combustion engine 3.1 and the second power generator 5 an internal combustion engine 5.1 , In addition, each of the power producers assigns 3 . 5 at least one electric machine, here the first power generator 3 a first electric machine 3.2 and the second power generator 5 a second electric machine 5.2 , The electrical machines 3.2 . 5.2 On the one hand can be operated as generators, for example, by the internal combustion engines 3.1 . 5.1 be driven or by giving them deceleration performance of the motor vehicle 1 - Especially when recuperating - is supplied, on the other hand, they are operable as electric motors to electric power in propulsion or traction for the motor vehicle 1 to change. In particular, the electrical machines can 3.2 . 5.2 the internal combustion engines 3.1 . 5.1 support, especially at a high torque request to the power generator 3 . 5 On the other hand, they can be a load point of the internal combustion engine 3.1 . 5.1 by increasing additional load in regenerative operation, especially in a low load or partial load range, to cause the internal combustion engine 3.1 . 5.1 be operated at a more favorable operating point with respect to a specific fuel consumption and / or specific exhaust emissions.

The car 1 also has an electrical system 13 on, which prefers here with the intermediate circuit 11 electrically connected. Alternatively or additionally, it is preferably provided that the electrical system 13 with one of the high-voltage circuits 7 . 9 electrically connected. The electrical system 13 can thus directly over the high-voltage circuits 7 . 9 - if necessary, mediated via the DC link 11 - are supplied so that there are no dangerous, heavy and expensive lead acid batteries for low voltage supply of the electrical system 13 requirement. Furthermore, a start of the internal combustion engine 3.1 . 5.1 preferably also via the high-voltage circuits 7 . 9 and / or the intermediate circuit 11 causes, in particular starter of the internal combustion engine 3.1 . 5.1 over the high-voltage circuits 7 . 9 and / or the intermediate circuit 11 be supplied with electrical power. This improves the starting behavior of the internal combustion engine 3.1 . 5.1 and leads to a discharge in particular of the electrical components in the starting system.

The car 1 is designed here as a rail vehicle, in particular as a railcar, as a railcar or as a power car.

Like the motor vehicle 1 is shown in the figure, it preferably realizes a single traction, wherein it as a single railcar or power car, or as a single railcar is provided. However, it is possible to interconnect several such railcars, railcars or power cars and thus to realize a multiple traction. In this case, the DC link extends 11 Preferably, a plurality of such vehicles, which are joined together as a part of a motor vehicle to a total motor vehicle.

As part of a method for operating the motor vehicle 1 becomes electrical power via the DC link 11 depending on at least one parameter of the power generator 3 . 5 and / or the motor vehicle 1 between the power producers 3 . 5 moved or distributed to these.

The at least one parameter is preferably selected from a group consisting of an operating state of the motor vehicle 1 , a current in the DC link 11 , an aging condition of the power generator 3 . 5 , an aging condition of high-voltage batteries 15 . 17 - Here is a first high-voltage battery 15 the first power generator 3 is associated with a second high-voltage battery 17 the second power generator 5 is assigned, and wherein the high-voltage batteries 15 . 17 are preferably designed as high-voltage lithium batteries -, and a current state of charge of the high-voltage batteries 15 . 17 , It is particularly possible maintenance intervals for the power generator 3 . 5 and / or the high-voltage batteries 15 . 17 to optimize and / or to synchronize, in particular by a corresponding load distribution depending on their aging state and / or state of charge is selected. It is also possible, the life of the high-voltage batteries and / or the power generator 3 . 5 to increase, in particular by being less burdened by an adapted power distribution, especially in the peak load range, as if they are separately without the DC link 11 would work. It also shows that a failure of a high-voltage battery 15 . 17 can be tolerated because of electrical power over the unaffected high-voltage circuit 7 . 9 can be provided, either via its high-voltage battery 15 . 17 and / or via the electrical machine 3.2 . 5.2 ,

Furthermore, it is possible via the DC link 11 predetermined charge / discharge cycles for the high-voltage batteries 15 . 17 the power generator 3 . 5 to perform, so to speak, a continuous care of the high-voltage batteries 15 . 17 , in particular in the manner of a "battery gymnastics", can take place. Regularly performed charge / discharge cycles can contribute to the life of the high-voltage batteries 15 . 17 to increase. During such predetermined charge / discharge cycles, electrical energy is transferred through the DC link 11 between the high-voltage batteries 15 . 17 postponed. For example, it is possible that the first high-voltage battery 15 is discharged, with the electrical energy stored there temporarily the second high-voltage battery 17 and / or one of the electrical machines 3.2 . 5.2 is supplied to generate drive power. To recharge the first high-voltage battery 15 will then be according to the second high-voltage battery 17 electrical energy taken, and / or the charging energy is through one of the two electrical machines 3.2 . 5.2 generated. Conversely, of course, for the second high-voltage battery 17 be proceeded.

Furthermore, it is possible that in an operating state of the motor vehicle 1 a first power producer 3 . 5 generates combustion engine power and electric power, wherein a second power generator 5 . 3 from the first power generator 3 . 5 generated electrical power is supplied to a purely electrical supply of drive power. It is possible, for example - without limiting the general public - that the first power generator 3 with the internal combustion engine 3.1 generates both drive power, and acting as a generator, the first electric machine 3.2 drives, so that is generated by this electrical power. This electrical power is via the DC link 11 the second power generator 5 fed to its internal combustion engine 5.1 does not generate drive power by either idling or being shut down. The electric power is but in acting as an electric motor, the second electric machine 5.2 converted into drive power. Of course, a reverse drive is possible. The operating state described here is particularly preferred for a slow drive of the motor vehicle 1 be used, for example, for a ride of the rail vehicle by a car wash. In particular, an electric drive is implemented on one side and a diesel-electric drive on the other side. It is thereby possible for the one internal combustion engine 3.1 . 5.1 which actually generates drive power to set a higher load point than if both engines were to produce drive power. As a result, this internal combustion engine can be operated at a more efficient operating point, both in terms of specific fuel consumption and specific exhaust emissions.

2 shows a schematic representation of a second embodiment of a motor vehicle 1 , Identical and functionally identical elements are provided with the same reference numerals, so that reference is made to the preceding description. The car 1 is designed as a railcar and has two motor vehicle parts, namely a first motor vehicle part 1.1 and a second Automotive part 1.2 , The first motor vehicle part 1.1 has a first power generator 3 on, wherein the second motor vehicle part 1.2 a second power generator 5 having. The power producers 3 . 5 serve the generation of drive power and are each one here schematically represented by a differential gear set 19.1 . 19.2 or a drive bogie assigned to the drive.

In the second embodiment of the motor vehicle 1 is the first power generator 3 designed as a diesel-electric drive. He has an internal combustion engine 3.1 on, with a first electric machine rubbed as a generator 3.2 is operatively connected to the drive. The first electric machine 3.2 is via a first high-voltage circuit 7 with a second electric machine 3.3 operatively connected, which operates as a motor, being from the first electric machine 3.2 generated electrical power converts into drive power and in particular with the wheelset 19.1 is operatively connected to the drive.

With the first high-voltage circuit 7 is also at least an auxiliary output 21 electrically connected.

The second power generator 5 is designed as a purely electric drive and has only one electrical machine 5.2 on. This is via a second high-voltage circuit 9 with a high-voltage battery 17 electrically connected. The electric machine 5.2 is designed to convert electrical power into mechanical drive power, being with the second wheelset 19.2 is operatively connected to the drive.

With the second high-voltage circuit 9 is at least a second auxiliary output 23 electrically connected.

Via the DC link 11 are the two high-voltage circuits 7 . 9 electrically connected to each other. Thus, it is particularly possible from the first electric machine 3.2 generated electrical power in the high-voltage battery 17 to store and / or in the electric machine 5.2 of the second power generator 5 to convert into mechanical drive power and thus the second set of wheels 19.2 drive.

Delays the vehicle 1 it is also possible to use the second electric machine 3.3 and / or the electric machine 5.2 of the second power generator 5 operate as a generator and recuperate energy, which then especially in the high-voltage battery 17 can be stored. This can be done with the DC link 11 especially from the second electric machine 3.3 of the first power generator 3 recuperated electrical power in the second motor vehicle part 1.2 arranged high-voltage battery 17 be supplied.

Of course, an embodiment is possible in which the high-voltage battery 17 in the first motor vehicle part 1.1 is arranged.

Overall, the configuration of power generators 3 . 5 in the second embodiment of the motor vehicle 1 according to 2 be considered as a serial hybrid drive.

3 shows a schematic representation of a third embodiment of a motor vehicle 1 , Identical and functionally identical elements are provided with the same reference numerals, so that reference is made to the preceding description. In this embodiment, the two power generators 3 . 5 in the two motor vehicle parts 1.1 . 1.2 each designed as a hybrid drives, each with an internal combustion engine 3.1 . 5.1 with an electric machine 3.2 . 5.2 is operatively connected, and being the electrical machines 3.2 . 5.2 - Operating point dependent - are operable as a motor and as a generator. They are each here via a clutch-gear unit 25 . 27 with the wheelsets 19.1 . 19.2 operatively connected to their drive. Every hybrid power generator 3 . 5 has a high-voltage circuit 7 . 9 on, with each of the high-voltage circuits 7 . 9 a high-voltage battery 15 . 17 assigned. Furthermore, every high-voltage circuit 7 . 9 in each case at least one power take-off 21 . 23 assigned.

The two high-voltage circuits 7 . 9 are over the DC link 11 connected with each other. This connection enables a more extensive, flexible and diversified distribution of drive and brake functions to the individual power generators 3 . 5 than with separate high-voltage circuits 7 . 9 the case would be. In addition, electrical power can be between the high-voltage circuits 7 . 9 be relocated as needed.

The design of the power generator 3 . 5 according to the third embodiment according to 3 can also be understood as a parallel hybrid drive.

4 shows a schematic representation of a fourth embodiment of a motor vehicle 1 , Identical and functionally identical elements are provided with the same reference numerals, so that reference is made to the preceding description. In this embodiment, the first power generator 3 in the first motor vehicle part 1.1 designed as a hybrid drive, as in connection with the first power generator 3 of the third embodiment according to 3 was explained. However, here is in addition to the at least one of the first high-voltage circuit 7 associated power take-off 21 a mechanical power take-off 21 ' provided here by the electric machine 3.2 of the first power generator 3 is mechanically driven.

The second power generator 5 in the second motor vehicle part 1.2 is designed as a purely electric drive and has only one electrical machine 5.2 auf, which - as in connection with the second embodiment according to 2 explained - with the second set of wheels 19.2 is operatively connected to the drive.

In the second motor vehicle part 1.2 is also a high-voltage battery 17 provided with the second high-voltage circuit 9 electrically connected. With this is also a second, electrical power take-off 23 connected.

The high-voltage circuits 7 . 9 are in turn via the DC link 11 electrically connected to each other.

Such an embodiment of the combination of power producers 3 . 5 according to 4 can also be understood as a hybrid hybrid drive.

Overall, it shows that using the motor vehicle 1 and the method in particular an availability of the power generator 3 . 5 but also the high-voltage batteries 15 . 17 and ultimately also of the electrical system 13 can be improved. In particular, a failure of components, such as a high-voltage battery 15 . 17 and / or a power generator 2 . 5 be at least partially compensated. It also results in an improvement in the life cycle costs of high-voltage batteries 15 . 17 as well as the internal combustion engines 3.1 . 5.1 , The internal combustion engine 3.1 . 5.1 are preferably designed as diesel engines, but there are also other types of engine conceivable. This results in an increased spring tolerance of the motor vehicle 1 against a failure of power producers 3 . 5 ,

Claims (8)

Motor vehicle ( 1 ) having at least two power generators ( 3 . 5 ), each power producer ( 3 . 5 ) at least one electric machine ( 3.2 . 5.2 ) and a high-voltage circuit ( 7 . 9 ), characterized in that the high-voltage circuits ( 7 . 9 ) of the at least two power generators ( 3 . 5 ) are electrically connected together. Motor vehicle ( 1 ) according to claim 1, characterized in that the high-voltage circuits ( 7 . 9 ) via a DC link ( 11 ), in particular via a DC link, are connected. Motor vehicle ( 1 ) according to one of the preceding claims, characterized in that a vehicle electrical system ( 13 ) of the motor vehicle ( 1 ) with one of the high-voltage circuits ( 7 . 9 ) and / or with the intermediate circuit ( 11 ) connected is. Motor vehicle ( 1 ) according to one of the preceding claims, characterized in that the motor vehicle ( 1 ) is designed as a rail vehicle, in particular as a railcar, as a railcar or as a power car. Method for operating a motor vehicle ( 1 ), in particular a motor vehicle according to one of claims 1 to 4, wherein a motor vehicle ( 1 ) which comprises at least two power generators ( 3 . 5 ), each power generator ( 3 . 5 ) at least one electric machine ( 3.2 . 5.2 ) and a high-voltage circuit ( 7 . 9 ), wherein the high-voltage circuits ( 7 . 9 ) of the at least two power generators ( 3 . 5 ) electrically - preferably via a DC link ( 11 ), Wherein preferably electrical power or electrical energy via the intermediate circuit ( 11 ) in dependence on at least one parameter of the power generator ( 3 . 5 ) and / or the motor vehicle ( 1 ) between the generators ( 3 . 5 ) or to the power producers ( 3 . 5 ) is distributed. A method according to claim 5, characterized in that the at least one parameter is selected from a group consisting of an operating state of the motor vehicle ( 1 ), a current in the DC link ( 11 ), an aging condition of the power producers ( 3 . 5 ), an aging condition of high-voltage batteries ( 15 . 17 ) of the power producers ( 3 . 5 ), and a current state of charge of the high-voltage batteries ( 15 . 17 ). Method according to one of claims 5 and 6, characterized in that via the intermediate circuit ( 11 ) predetermined charging and / or discharging cycles for the high-voltage batteries ( 15 . 17 ) of the power producers ( 3 . 5 ), whereby electrical energy is supplied via the intermediate circuit ( 11 ) between the high-voltage batteries ( 15 . 17 ) of the various power producers ( 3 . 5 ) is moved. Method according to one of claims 5 to 7, characterized in that in an operating state of the motor vehicle ( 1 ) a first power producer ( 3 . 5 ) generates combustion engine power and electric power, wherein a second power generator ( 5 . 3 ) from the first power producer ( 3 . 5 ) generated electrical Power is supplied to the purely electrical supply of drive power.

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