CN111319516B

CN111319516B - System for an electric vehicle incorporating a road

Info

Publication number: CN111319516B
Application number: CN201911282290.2A
Authority: CN
Inventors: R.孔茨勒; H.瑙曼
Original assignee: Volkswagen AG
Current assignee: Volkswagen AG
Priority date: 2018-12-14
Filing date: 2019-12-13
Publication date: 2023-04-07
Anticipated expiration: 2039-12-13
Also published as: DE102018221741A1; CN111319516A; DE102018221741B4

Abstract

The present invention relates to a system for an electric vehicle incorporating a road, in particular the present invention relates to a system for the energy supply of an electric vehicle, which is innovatively solved by protective measures against electric shocks of a vehicle running on electric current. The systems are designed in this connection as TN-C systems, TN-S systems and TN-C-S systems. It is provided that an additional second protective conductor (22) is provided, which is connected parallel to the first protective conductor (20) or the trolley line comprises two operating current conductors (18), and that at least one protective conductor (20) is provided and the vehicle (12) can be connected to the trolley line via the first current collector (14) and to the protective conductor (20) via the second current collector (14) and the second current collector (14) is connected to at least one potential compensation (32) of the vehicle (12).

Description

System for an electric vehicle incorporating a road

Technical Field

The invention relates to a system for the current supply of a road-bound (stra β engebenden, sometimes referred to as road-related) vehicle, wherein at least one electrical consumer of the road-bound vehicle can be connected to a trolley line (fahrleitring) of a voltage supply network via at least one current collector and the trolley line comprises two operating current conductors.

Background

For the operation of vehicles on overhead lines or for the supply of vehicles with electrical energy from overhead lines, measures for protecting personnel against the danger of electrical currents are necessary. The basic measures for this are defined in DIN VDE 0100-410. It generally consists of two protective measures independent of one another and is divided into basic protection and protection against the effects of faults in the installation or in the operating device.

The use of protective safeguards in different levels of electrical operating devices is described in VDE 0140-1. Protection against electrical shocks caused by double or reinforced insulation is ensured in protection class II. Due to the high requirements for insulation, a correspondingly high insulation use, in particular in the region of the drive train, is hereby obtained for the vehicle, in addition, by the conductive body.

An alternative protection concept is described by the protection conductor system at protection level I. It is important here that the touch-sensitive and electrically conductive parts of the operating element, in addition to the base protection, are connected to what is known as a protection conductor (PE). The protective conductor connection ensures, in the first place, that the conductive parts of the operating components are subject to potential equalisation (sometimes referred to as potential compensation) and therefore dangerous contact voltages cannot occur in the event of simultaneous contact by a person with the bodies of different operating components. This potential equalization is combined with an automatic switching-off device which, in the event of a fault (electrical connection of the voltage-carrying conductors to the conductive body of the operating component, a so-called chassis), forces a switching-off of the component or installation part, so that the fault does not occur permanently (anstehen). The protective conductor connection must be determined such that the overcurrent or fault current protection device is switched off in the required time.

The determined network forms are differentiated according to the implementation form of the protection conductor or according to the form of the ground connection of the protection conductor. In so-called TN-C systems, the neutral conductor (N) and the protective conductor (PE) conducting the operating current are physically implemented together in a common conductor (PEN). Since in this case not only the operating current but also the fault current must flow via the conductor, special requirements arise. It is decisive for the efficiency of the protective device and for the maximum reliable maintenance of the touch voltage that the so-called loop impedance does not exceed a certain value. In addition to the contact of the wire, the wire cross section has a significant effect on the loop impedance.

In the case of current distribution in overhead line systems supplied by vehicles with lines (leitongsufung) connected to the poles, a particularly high outlay for the overall transmission results in an increase in the line cross section. The maintenance of the required low loop impedance with the conductor combined by PE and L as an overhead conductor is only very difficult to achieve or even impossible depending on the operating conditions. Another difficult situation is given by the operational grounding of the voltage generator: the voltage drop, which is determined by the current flow on all return conductors (PEL-), generates a potential difference with respect to the position of the vehicle, which can be eliminated by a person in the event of a fault.

A system is known from EP 2 792 530 A1, which in the case of a vehicle can be operated by means of an electric current via a connection to a trolley line.

Disclosure of Invention

The invention is based on the object of providing a system which is associated with a low expenditure with high efficiency.

In a first embodiment of the invention, it is provided that an additional second protective conductor is provided, which is connected parallel to the first protective conductor. Advantageously, the electrical resistance is thereby reduced. Preferably, the maximum reliable touch voltage is not exceeded in the event of a fault. Advantageously, the power losses are reduced in the operating situation.

A road-bound vehicle is to be understood as meaning, in particular, a load-carrying vehicle (LKW), a trolley bus (trollebus) or a passenger car (PKW).

The current supply is to be understood in particular as a direct current supply or an alternating current supply.

An electric consumer is to be understood in particular as an electric motor. The electric motor is integrated in particular into an electric circuit. The electric motor is in particular coupled to a potential balance. The term potential equilibrium is to be understood in particular to mean an electrically conductive connection which minimizes the potential between conductive bodies in the vehicle. The circuit comprises in particular a DC/DC converter. The input and output of the DC/DC converter are in particular not galvanically separated. The DC/DC converter is coupled in particular to a potential balance. The circuit comprises in particular an AC/DC converter. The input and output of the AC/DC converter are in particular not galvanically separated. The AC/DC converter is coupled in particular to a potential balance. The circuit comprises in particular an AC/AC converter. The input and output of the AC/AC converter are in particular not galvanically separated. The AC/AC converter is coupled in particular to a potential balance. The circuit comprises in particular a DC/AC converter. The input and output of the DC/AC converter are in particular not galvanically separated. The DC/AC converter is coupled in particular to a potential balance. The circuit comprises, inter alia, a fault current protection switch.

A current collector is to be understood in particular as a device for electrical connection between a trolley line and an electrical consumer of a vehicle that is associated with a roadway. In particular, current collectors are understood to be pantographs (pantographs).

A voltage supply network is to be understood to mean, in particular, a system which comprises at least two operating current conductors, at least one protective conductor and at least one substation. The substation is connected to a trolley line for inputting a supply voltage. The substation comprises in particular at least one operating ground, which is provided for grounding the protection conductor. The substation comprises in particular an overcurrent protection device which is provided in particular for protecting the operating current conductor which conducts the positive potential. The substation comprises in particular at least one rectifier or inverter, to which two operating current conductors are coupled. The rectifier or the inverter is in particular coupled to an energy generation source or an energy storage medium.

A running current conductor is to be understood to mean, in particular, a conductor which conducts a positive or negative potential at which a direct voltage is present. A protective conductor is to be understood in particular as a conductor for protection against electrical shocks from the protection class I. In particular, the protective conductor is provided to protect personnel against the danger of electric currents. In particular, a protection for increasing the service life of the electrical component is provided. The protective conductor is in particular coupled to a potential balance within the vehicle.

In a preferred embodiment of the invention, it is provided that the trolley line is an overhead line guided on the pole. Advantageously, the production costs and assembly effort are thereby reduced. Advantageously, increased operational safety is thereby ensured.

A utility pole is to be understood as meaning in particular a suspended power transmission tower (freeleitungsmat) for trolley lines and/or protective lines.

An overhead line guided on a utility pole is to be understood to mean, in particular, a plurality of utility poles, at which at least two operating current conductors are fastened on a travel rail.

In a further embodiment of the invention, it is preferably provided that the second protective conductor runs parallel to the direction of travel and in or on a track for the vehicle. Advantageously, increased operational safety and reduced power losses during operating situations are thereby ensured.

In the travel path, this is to be understood in particular as being in the soil layer of the travel path. On a running rail should be understood in particular to mean on the surface of the running rail or the outer edge region of the running rail relative to the ground environment.

In a further preferred embodiment of the invention, it is provided that the second protective conductor is connected to the first protective conductor via a pole. Preferably, the utility pole consists of an electrically conductive material and is provided in particular for guiding the operating current conductor. In particular, the utility pole is provided as a protective conductor for the connection of the first protective conductor to the second protective conductor. Preferably, the second protection conductor is guided along the pole and is connected to the first protection conductor via a direct electrical connection. Advantageously, increased operating safety and reduced power losses during operating situations are thereby ensured.

In a preferred embodiment of the invention, it is provided that the second guard conductor and the first guard conductor are identical to one another at least in some regions. Advantageously, a compact design is thereby ensured.

The same construction as one another is to be understood in particular to mean that the two conductors have the same cross section, in particular the same material, and in particular converge to one conductor.

In a second embodiment of the invention, it is provided that the trolley line comprises two operating current conductors and that at least one protective conductor is provided, and that the vehicle can be connected to the trolley line via a first current collector and to the protective conductor via a second current collector, and that the second current collector is connected to at least one potential compensation connection (sometimes referred to as a potential compensation port) of the vehicle. Advantageously, increased operational safety is ensured and power losses in the operating situation are reduced in this way.

In a further preferred embodiment of the invention, it is provided that the protective conductor extends above the vehicle. Advantageously, operational safety is thereby increased.

Above, the protective conductor is to be understood in particular to be guided at the pole.

In a further embodiment of the invention, it is provided that the road-bound vehicle has at least one consumer (which contains a current supply via a trolley line) which can be operated with current, has at least one first current collector for connection to an operating current conductor of the trolley line, and has a second current collector, which is connected to a potential compensation connection of the vehicle and which is contactable with an additional protective conductor of the current supply. Advantageously, power losses in the operating situation are thereby reduced and operating safety is increased.

The different embodiments of the invention mentioned in this document can be advantageously combined with one another as long as they are not explicitly stated otherwise.

Drawings

The invention is subsequently explained in embodiments in accordance with the figures. Wherein:

figure 1 shows a first embodiment variant of a system for an electric vehicle,

figure 2 shows a second embodiment variant of the system for an electric vehicle,

fig. 3 shows a third embodiment variant of the system for an electric vehicle.

REFERENCE SIGNS LIST

10. Electric consumption device

12. Vehicle combined with road

14. Current collector

16. Current sink

18. Operating current conductor

20. First protective conductor

22. Second protective conductor

26. Telegraph pole

28. Direction of travel

30. Running track

32. Potential balancing

34 DC/DC converter

36. Fault current protection switch

38. Transformer substation

40. Operation grounding

42. Overcurrent protection device

44. A rectifier.

Detailed Description

Fig. 1 shows a first embodiment variant of a system for an electric vehicle. The system includes a substation 38 with a rectifier 44 and an overcurrent protection device 42 associated with the positive operating current conductor 18. The first embodiment corresponds to a TN — C system, in which the negative operating current conductor 18 (neutral conductor) is formed in at least one partial region in the same manner as the first protective conductor 20. In addition to the first screen conductor 20, the second screen conductor 22 extends parallel to the direction of travel 28 in the ground layer of the travel rail 30. The second shield conductor 22 is in particular insulated in order to avoid stray currents (Streustrom, sometimes referred to as stray currents) into the earth layer. The first and

second guard conductors

20, 22 converge and are coupled to the operating ground 40 at least in the substation 38. Furthermore, the first embodiment variant comprises a road-bound vehicle 12 which is coupled via two current collectors 14 to a first protective conductor 20 and to a negatively charged operating current conductor 18, as well as to a positive operating current conductor 18. Within the vehicle 12, the voltage is converted into the required voltage of the electrical consumer 10 via a DC/DC converter 34. Furthermore, the vehicle 12 comprises three potential balances 32, wherein the potential balances 32 are arranged directly next to the current sink 16, which is in particular additionally insulated. A further potential balance 32 is arranged next to the DC/DC converter 34. The third potential balance 32 is arranged next to the electrical consumer 10.

Fig. 2 shows a second embodiment variant of the system for an electric vehicle. The system comprises a substation 38 with a rectifier 44 and an overcurrent protection device 42, which operates the current conductor 18 in connection with a positive direct voltage. The second embodiment variant corresponds to a TN-S system, in which the positive operating current conductor 18, the negative operating current conductor 18 and the protective conductor 20 are arranged separately from one another. In this embodiment variant, only the protective conductor 20 is used, which is connected to the negative operating current conductor 18 and to the operating ground 40 in the substation. Furthermore, the second embodiment variant comprises a road-bound vehicle 12 which is coupled via three current collectors 14 to the first protective conductor 20, to the negative operating current conductor 18 and to the positive operating current conductor 18, respectively. Within the vehicle 12, the voltage is converted into the required voltage of the electrical load 10 via a DC/DC converter 34. Furthermore, the vehicle 12 comprises three potential balances 32, wherein the potential balances 32 are arranged in the vehicle after the coupling of the protection conductor 20 via the current collector 14. This potential balance is not in direct electrical connection to the

further component

16,34, 10. The second potential balance 32 is arranged directly next to the DC/DC converter 34. The third potential balance 32 is arranged directly next to the electrical load 10. The collectors 14 for the negative operating current conductor 18 and the positive operating current conductor 18 are connected directly to the current sink 16, which in turn is connected directly to the DC/DC converter 34 and to the electrical load 10. The current sink 16 is insulated and comprises in particular a fault current protection switch 36.

Fig. 3 shows a third embodiment variant of the system for an electric vehicle. The system comprises a substation 38 with a rectifier 44 and an overcurrent protection device 42, which operates the current conductor 18 in connection with a positive direct voltage. The third embodiment corresponds to a TN-C-S system, in which the negative operating current conductor 18 is formed in at least one partial region in the same manner as the first protective conductor 20. In addition to the first screen conductor 20, the second screen conductor 22 extends parallel to the direction of travel 28 in the soil of the travel rail 30. The second screen conductor 22 is in particular insulated in order to avoid stray currents into the earth. The first and

second guard conductors

20, 22 converge and are coupled to the operating ground 40 at least in the substation 38. Furthermore, the third embodiment variant comprises a road-bound vehicle 12 which is coupled to the first protective conductor 20 and the negative operating current conductor 18, as well as the positive operating current conductor 18, via two current collectors 14. Within the vehicle 12, the voltage is converted via a DC/DC converter 34 into the required voltage of the electrical consumer 10. Furthermore, the vehicle 12 comprises two potential balances 32, wherein the potential balance 32 is arranged directly next to the DC/DC converter 34 and the potential balance 32 is arranged directly next to the electrical consumer 10. The current collector 16 comprises, inter alia, a fault current protection switch 36.

Claims

1. A system for the current supply of a road-bound vehicle (12), wherein at least one electrical consumer (10) of the road-bound vehicle (12) can be connected via at least one current collector with a trolley line of a voltage supply network, and the trolley line comprises two operating current conductors (18), from which the operating current conductors (18) simultaneously form a first protection conductor (20), characterized in that an additional second protection conductor (22) is provided, which is coupled parallel to the first protection conductor (20).

2. The system of claim 1, wherein the trolley line is an overhead conductor routed at a utility pole (26).

3. The system according to claim 1 or 2, characterized in that the second protective conductor (22) runs parallel to the direction of travel (28) in or on a running track (30) for the vehicle (12).

4. The system according to claim 2, characterized in that the second protection conductor (22) is conductively connected with the first protection conductor (20) via the utility pole (26) of the overhead conductor.

5. System according to claim 1 or 2, characterized in that the second protective conductor (22) and the first protective conductor (20) are constructed identically to one another at least in partial regions.

6. A system for current supply of a road-bound vehicle (12), wherein at least one electrical consumer (10) of the road-bound vehicle (12) can be connected via at least one first current collector with a trolley line of a voltage supply network, characterized in that the trolley line comprises two operating current conductors (18) and is provided with at least one protection conductor (20) and the vehicle (12) can be connected via the first current collector with the trolley line and via a second current collector with the protection conductor (20) and the second current collector with at least one potential balance (32) of the vehicle (12).

7. The system according to claim 6, characterized in that the protective conductor (20) extends above the vehicle (12).

8. A road-bound vehicle (12) with at least one consumer which can be operated with electric current, comprising an electric current supply via a trolley line, with at least one first current collector for connection to an operating current conductor (18) of the trolley line, characterized by a second current collector which is connected to a potential balance (32) of the vehicle (12) and which can be brought into contact with an additional protective conductor (20) of the electric current supply.