DE102019116443A1 - Power rail for a roadway - Google Patents

Abstract

The invention relates to a busbar along the roadway for the power supply of electrically operated motor vehicles, characterized in that the contact surfaces (1, 3) of this busbar are arranged next to one another and that they are separated by an insulating central web (6).

Description

Technical field

The invention relates to a busbar for a roadway according to the preamble of claim 1.

State of the art

Various approaches are known for supplying vehicles with electrical energy directly while driving. In addition to the power supply via an overhead line, as has been known from railways for decades, other alternative solutions have been developed in recent decades. Alstom, for example, offers a track for trams embedded in the carriageway, which switches on a voltage while driving over it. The tram rail provides the negative pole.

Other known solutions are an inductive coupling of induction loops embedded in the carriageway, which charge the batteries of buses at bus stops. Various variants of busbars are also known which, after a channel has been milled out in the asphalt, are let into the carriageway and, via a pantograph attached to the underside of the vehicle, enable a power supply for trucks and cars.

A busbar is also known which is not embedded in the carriageway but is attached to the carriageway covering. However, this solution has only one current contact track, which is divided into short segments and permanently changes the polarity. For power transmission into the vehicle, two pantographs arranged one behind the other are necessary on the underbody. A control unit is also required to switch off the segment after each segment end (max. Approx. 1 meter long). The shape of these busbars is not suitable to accommodate powerful supply lines. This also has no profile shape to enable a steering guidance acting on a mechanical basis. Although there are various possibilities for contactless sensing of lines, it is advantageous for a safe steering guidance to use a sensor that works on a mechanical basis with the aid of a profile.

Most of the rail concepts developed so far are integrated in the carriageway. For this purpose, the asphalt surface must be milled out, especially when retrofitting the busbar, and after inserting the busbar e.g. can be closed again by pouring out. The incorporation into the road surface provides good mechanical protection, but represents an additional effort and weakens the cohesion of the road surface due to the deep milling. Removing the water in the deep slot is also difficult in rain or snow. Maintenance and repair work are also difficult to carry out. The tracking resistance is a problem especially in difficult weather conditions.

In addition to ensuring sufficient high-voltage strength even in extreme weather conditions, busbars are also subject to high mechanical loads during the drive over e.g. exposed to trucks and signs of wear due to intensive use. Furthermore, large amounts of energy are transmitted via the busbar, so that the mechanical and electrical design of the power supply lines and their heat dissipation behavior also play an important role.

Object of the invention

The object of the present invention is to overcome the disadvantages of the prior art. In particular, a conductor rail is to be made available which has a very flat structure in its shape and at the same time has a large width. This form of the conductor rail is preferably placed on the surface of the carriageway or introduced with only a small installation depth.

Solution of the task

The features according to claim 1 lead to the achievement of the object.

Advantageous refinements are described in the subclaims.
The invention relates to a method for supplying vehicles with electricity from the road while driving. This enables vehicles to be guided fully automatically and reliably with regard to their steering, speed and vehicle distance. At the same time, batteries are charged while driving. For this purpose, a conductor rail is attached to the surface of a road surface and is scanned with the aid of a pantograph placed on the underbody of the vehicles. Communication between the vehicle and the power rail transmits precise vehicle speed and vehicle position and thus also precisely and reliably the vehicle distance.

The low height of the conductor rail enables problem-free driving over and, if necessary, only a small amount of entry into the road surface. The wide design allows wide insulation areas along the contact areas and thus high tracking resistance of the live contact areas. Supply lines in the form of stacked sheet metal plates enable a maximum of conductor cross-section, heat dissipation and vertical resilience. The division of the sheet metal into braided strips improves linear expansion behavior and elasticity. As an alternative to this, a superconductor can also be used to enable the high currents, in particular with a minimal vehicle distance. This also reduces the number of current feed points for the superconductor. A center bar with gutters on both sides enables safe steering guidance, increases the surface distance between the two current contact surfaces and thus increases the tracking resistance.

A busbar is therefore proposed which has a broad and flat design in terms of its shape.

• • Breite Anordnung mit niedriger Bauhöhe ermöglicht einfaches Überfahren der Stromschiene
• • Einfache Montage der Stromschiene auf Fahrbahnoberfläche durch Kleben bzw. Anschrauben
• • Einfacher Zugang zur Stromschiene bei Service- und Reparaturarbeiten sowie Schienentausch
• • Einfaches, zuverlässiges Abführen von Regenwasser (Schiene höher als Fahrbahnoberfläche)
• • Breite Ausgestaltung der Schiene ermöglicht eine hohe Isolationsfestigkeit durch breite Isolierflächen zwischen den beiden stromführenden Kontaktflächen sowie an den Rändern
• • Isolierender Mittelsteg 6 mit beidseitiger ebenfalls isolierender Rinne ermöglicht eine hohe Kriechstromfestigkeit - wichtig bei Verdoppelung der Spannungshöhe
• • Die schrägen Kontaktflächen 2 ermöglichen eine mechanisch basierende Führung des Stromabnehmers und damit auch eine zuverlässige Lenkungsführung des Fahrzeugs
• • Leistungsstarke Stromversorgung innerhalb der Schiene wird ermöglicht durch die beiden Versorgungsleitungen in Form mehrerer aufeinander gestapelter Blechplatten. Dadurch ergeben sich folgende Besonderheiten:
  • • Vertikale Elastizität, um sich an Unebenheiten der Fahrbahnoberfläche anzupassen
  • • Optimale Raumnutzung des Blechplattenpakets innerhalb der Schiene ermöglicht großen Querschnitt der Stromversorgung und damit großen Abstand zwischen jeweiligen Strom-Einspeisepunkten
  • • Hohe mechanische Belastbarkeit beim Überfahren der Schiene z.B. durch LKW's
  • • Maximale Leistungsübertragung der beiden Versorgungsleitungen
  • • Verdopplung der Fahrzeugversorgungsspannung durch Anlegen einer negativer Versorgungsspannung an Stelle von GND-Potential □ Doppelte Versorgungsspannung und folglich halbierter Strom führt bei gegebenem Leiterquerschnitt der Kupferbleche zur Verdopplung des Abstands der Versorgungseinspeisung
  • • Maximale Wärmeableitung durch flache Formgebung der gestapelten Kupferbleche
  • • Dünne Isolierschicht mit guter Wärmeleitung zwischen Kupferblechunterseite und Metallbodenplatte ergibt gute Wärmeableitung gegenüber Fahrbahnoberfläche
  • • Begrenzung auf maximal zulässiger Temperatur der Versorgungsleitungen durch permanente Temperaturmessung und ggf. Reduzierung des Stroms zu den Fahrzeugen. Die Reduzierung des Ladestroms zum jeweiligen Fahrzeug erfolgt in Abhängigkeit des Akkuladezustands und der noch geplanten Fahrzeit entlang der Stromschiene
  • • Alternativ Einsatz eines Supraleiters an Stelle von klassischen Stromleitungen
• • Aktivieren der Stromschiene erfolgt durch Verbinden der positiven Versorgungsspannung mit der Kontaktfläche sowie der negativen Versorgungsspannung mit der Kontaktfläche
• • Mit Abschalten der Spannungen an den beiden Kontaktflächen 1, 3 werden beide Kontaktflächen und mit Gehäusepotential (GND) der elektrisch leitenden Trägerplatte verbunden.
• • Entwässern der seitlich des Mittelstegs angeordneten Rinnen erfolgt durch die in der Stromschiene integrierten Entwässerungskanäle oder kleinen in der Scheine integrierte Pumpen
• • Heizelemente oder eine Heizfolie entlang der jeweiligen Entwässerungskanäle sowie nahe der beiden Kontaktflächen sichern einen ungehinderten Abfluss des Wassers bei Frost sowie ein Schmelzen und damit Beseitigen des Schnees bei Schneefall.
• • Befestigen der Stromschiene auf der Fahrbahn erfolgt mittels Klebung, ggf. zusätzlich mit Asphaltdübeln
• • Einfache Austauschmöglichkeit der beiden z.B. aus Blechstreifen bestehenden Kontaktflächen infolge intensiver Nutzung und Materialabtrags durch einrastende Profilnasen.
• • Verhindern schädlicher Längenänderung der Versorgungsleitungen infolge hoher Temperaturschwankungen durch Bilden schmaler, übereinander platzierter Blechstreifen in verflochtener Art (s. 6) an Stelle massiver Blechplatten

The conductor rail described below has the following special features and advantages:

• • Wide arrangement with a low overall height enables the conductor rail to be easily passed over
• • Easy mounting of the conductor rail on the road surface by gluing or screwing
• • Easy access to the power rail for service and repair work as well as rail replacement
• • Simple, reliable drainage of rainwater (rail higher than road surface)
• • Wide design of the rail enables a high level of insulation strength thanks to wide insulating surfaces between the two current-carrying contact surfaces and at the edges
• • Insulating center bar 6 with a double-sided also insulating channel enables a high tracking resistance - important when the voltage level is doubled
• • The sloping contact surfaces 2nd enable mechanically based guidance of the pantograph and thus also reliable guidance of the vehicle
• • Powerful power supply within the rail is made possible by the two supply lines in the form of several stacked sheet metal plates. This results in the following special features:
  • • Vertical elasticity to adapt to unevenness on the road surface
  • • Optimal use of space of the sheet metal plate package within the rail enables a large cross-section of the power supply and thus a large distance between the respective power feed-in points
  • • High mechanical resilience when driving over the rail, for example by trucks
  • • Maximum power transmission of the two supply lines
  • • Doubling of the vehicle supply voltage by applying a negative supply voltage instead of GND potential □ Double supply voltage and consequently halved current leads to a doubling of the distance between the supply feed for a given conductor cross section of the copper sheets
  • • Maximum heat dissipation due to the flat shape of the stacked copper sheets
  • • Thin insulating layer with good heat conduction between the underside of copper sheet and metal base plate results in good heat dissipation from the road surface
  • • Limitation to the maximum permissible temperature of the supply lines through permanent temperature measurement and possibly reducing the current to the vehicles. The charge current to the respective vehicle is reduced depending on the battery charge level and the planned travel time along the power rail
  • • Alternatively, use of a superconductor instead of classic power lines
• • The busbar is activated by connecting the positive supply voltage to the contact surface and the negative supply voltage to the contact surface
• • By switching off the voltages on the two contact surfaces 1 , 3rd Both contact surfaces and with the housing potential (GND) of the electrically conductive carrier plate are connected.
• • The gutters arranged on the side of the central web are drained using the drainage channels integrated in the busbar or small pumps integrated in the banknotes
• • Heating elements or a heating foil along the respective drainage channels as well as near the two contact surfaces ensure an unimpeded drainage of the water in frost and a melting and thus removal of the snow in snowfall.
• • The conductor rail is fastened to the carriageway by means of adhesive, if necessary also with asphalt dowels
• • Easy exchange of the two contact surfaces, for example consisting of sheet metal strips, as a result of intensive use and material removal through snap-in profile lugs.
• • Prevent harmful changes in length of the supply lines due to high temperature fluctuations by forming narrow, interlaced sheet metal strips in an intertwined manner (see 6 ) instead of solid sheet metal

Figure description

• 1 shows a conductor rail in a sectional view which is attached to the road surface and the contact surfaces are easily interchangeable.
• 2nd shows like in 1 and 2nd a busbar, which is however at least partially embedded in the carriageway. The top of this variant has a slight slope towards the edges. The outer shell is completely covered with metal, so that the conductor rail can be completely shielded from metal.
• 3rd shows like in 1 and 2nd a track, which is also partially embedded in the road. The supply lines are equipped with a single-pole superconductor. The top of this variant also has a slight slope towards the edges.
• 4th shows like in 3rd a track, which is also partially embedded in the road. In addition to the supply line in the form of a superconductor 27 an additional power supply line for powering adjacent segment sections 1, 3 is also provided, so that the superconductor 27 does not require a supply output for every new segment section.
• 5 shows like in 3rd a functionally compatible busbar whose supply lines are equipped with a single-pole superconductor. Instead of a central web, this variant is equipped with a slot embedded in the carriageway, which is used to operate an autonomous recovery system for breakdown vehicles on a special route.
• 6 shows a plan view schematically the course of the power supply lines in the form of superconductors. The course of the coolant flow for the superconductor as well as the placement of the cooling units and their possibility of redundancy is shown.
• 7 shows a plan view of a section of a supply line 4th , 5 composed of a large number of narrow, sloping metal strips. These strips become on the respective lateral edges of these sheet metal layers composed of individual strips 30th bent over and continued in the level above in the opposite oblique direction.

Contact the busbar

In order to make it easy to contact the current collectors on the power rail, the contact surfaces of the power rail are placed next to each other on the surface. This enables easy contacting while traveling along the power rail. Reliable detection of the precise vehicle position and speed allows the track to be switched on and off safely, thus ensuring safe protection against contact.

Length of the contact areas that can be switched off

The length of the contact surfaces that can be switched off 1 and 3rd (from e.g. 10 to 20 meters) is determined by the requirements for contact protection. An increase in the segment length that can be switched off can be achieved by sensors on the front area of the vehicles (ultrasound, video, radar) scanning the roadway and, if a person entering the roadway is recognized, prompting the current active track segment to be switched off immediately.

Exchange of worn contact surfaces

The exchange of the contact surfaces due to wear can be automated. A longitudinal cut can be made on the contact surface to be replaced using a saw. This allows the contact area 1 , 3rd simply remove and then attach a new contact surface by simply snapping it into place.

Mechanical steering guidance

A mechanical steering guide is a very reliable and easy to use way to guide the pantograph precisely over the contact surfaces. This is an important function since the two contact areas to be tapped 1 , 3rd are placed directly next to each other.
The steering-related scanning of the busbar can be done on the inner slope 2nd of the contact areas 1 , 3rd or, if necessary, on the central bridge 6 respectively. In 2nd is shown a two-pole pantograph on the vehicle, which has the upper and inner surface of the contact surface 1 and 3rd scans.

Shielding the busbar

In 2nd is a variant of a busbar shown, which is completely of a metallic conductive housing is enclosed. During the inactive phase, the two contact surfaces 1, 3 are grounded via an electronic switch at both ends 12th , or. 25th connected to the housing. This means that the busbar is completely enclosed by a metallic or electromagnetically conductive shield material.

Maximum transmission power in supply lines

Due to the possibility of constant, precise and reliable detection of the vehicle position, conductor rails offer the prerequisite for reducing the distance between the individual vehicles. As a result, more vehicles can use this high-quality route, which, however, increases the necessary energy requirement many times over. The supply lines are thus exposed to very high currents, which has the largest possible conductor cross-section for both supply lines 4th and 5 makes necessary. In order to be able to compensate for height differences due to uneven road surfaces when laying the power track, the two supply lines are set 4th , 5 from a bundle of sheets stacked on top of each other.

Length expansion of the supply lines due to temperature change

The conductor rail consists of different materials that expand to different extents over temperature. In addition to the seasonal temperature fluctuations, there is additional strong self-heating due to the high supply currents of the busbar. Therefore, it is necessary to extend the length of the two supply lines 4th , 5 to neutralize.

Usually this is not a problem when using common power cables (stiff or with a strand). However, if the available installation space should enable maximum power transmission, the use of cables with a strand is not expedient. Since the conductor rail is also exposed to high vertical loads in addition to maximizing the conductor cross-section when being driven over by trucks, the two supply lines are therefore proposed 4th , 5 to be carried out in the form of narrow metal strips. As in 6 shown, instead of multi-layer sheets, the individual sheet layers each consist of a large number of sheet strips 30th , 32 , which are placed next to each other at a slight angle. These strips become on the respective edges of these sheet metal layers composed of strips 30th overturned 33 or welded and continued in the level above in the manner of braiding 32 . The distances 31 between the respective metal strips 30th or. 32 are minimal, so that the individual strips touch at minimal temperatures. These distances increase with increasing temperature, so that the width of the supply lines increases 4th , 5 slightly enlarged. The properties of these supply lines are therefore similar to those of cable strands (continuous individual cable cores), however, a maximum conductor cross-section and the high vertical load capacity are maintained. These narrow sheet metal strips can be produced by cutting the individual sheet metal layers into strips during the concertina-like folding of the sheet metal levels arranged one above the other with the aid of laser cutting.

Maximum distances for electricity entry points

Electricity feed-in points are located along the road at regular intervals, which supply the supply lines with electricity. For cost reasons, the aim is to make the distances between these electricity entry points as large as possible. In addition to the use of laminated cores / strips, it is therefore proposed not to use a positive and ground connection as in the previously known busbars, but to use a positive and negative pole. Compared to GND potential, one of the two supply lines has a voltage of, for example, +750 V, while the second supply line has a voltage of -750 V. The vehicle is thereby supplied with a voltage of 1500 V, which means that the current required is halved while the vehicle power remains the same, while the respective voltage level remains unchanged from the environment. The distance between two entry points can thus be doubled. The double voltage (eg 1500V here) is only present between the two contact surfaces. Through the two channels 7 there is an extension of the surface between the two contact surfaces, which significantly increases the tracking resistance.

Power supply using superconductors

In order to further increase the spacing for current feed points, it is proposed to equip the power supply lines with a superconductor. This makes it possible to transmit currents of several thousand amperes. The additional costs of the superconductor can be compensated for by significantly increasing the spacing of the power feed-in points, because the introduction of efficient supply lines is a technical challenge, especially in existing urban infrastructure, and is also associated with high costs.
The high permissible currents of the superconductor of several thousand amperes enable that even in the event of a failure in a rail section The subsequent busbar sections can be supplied from the other side. In the case of a star-shaped power supply, for example on the outskirts of the city, the supply of the other power rails is guaranteed in the event of a power rail section failing.

Voltage taps on superconductors

In addition to the supply line in the form of a superconductor 27 is an additional power supply line 18th provided for power supply to adjacent segment sections 1,3. It can be achieved that the superconductor 27 not need a supply outlet for every new segment section (e.g. every 10 to 20 meters). In addition to the two segments located directly at the superconductor output 1 , 3rd can via the two supply lines 18a , 18b also other adjacent segment sections 1 , 3rd are supplied and thus the distances between the individual superconductor outlets are significantly increased (for example to well over a hundred meters).

Cooling unit for cooling the refrigerant

The cooling of the superconductor can be done by cooling units see 50a, 50b in 5 at the respective end of a superconductor section 54 respectively. The sections can cover a length of approx. 1 to 2 km of a power rail.
The cooling units are as in 5 shown, placed at the beginning and end on the left and right side of the track. A cylindrical housing shape is proposed as the housing shape of the cooling unit. After drilling a hole in the roadway, a cylindrical tube with a solid bottom can be inserted into the borehole and filled with concrete or another highly thermally conductive material on the outside. The cooling unit is inserted into this cylindrical, sealed space and the space is filled with water or a suitable agent for better heat conduction. This means that there is good thermal conductivity for releasing the waste heat from the compressor to the surrounding earth. By designing all power and heat transfer lines with quick connectors or a quick connector on the supply lines of the refrigerant, there is the possibility of quick and easy replacement of the refrigeration unit in the event of a malfunction.

Redundant cooling system of the superconductor

In the event of a cooling unit failure, eg 50c, can be opened by opening two shut-off devices 53 a connection to the neighboring superconductor section and its cooling unit 50a getting produced. Every cooling unit 50a , 50c is designed in such a way that it can also cool the neighboring superconductor section sufficiently if necessary. This results in redundancy with regard to the failure of a cooling unit.
The shut-off devices 53 are remotely controllable so that they open automatically when a fault is detected. They can also be used to compensate for any loss of coolant in one of the sections. This can be done by briefly opening the shut-off devices 53 the coolant from a remotely located refill container above the system pressure the coolant from a section 54 forwarded to the next.

In the 1 to 4th is a first contact area 1 shown for power consumption by vehicle pantographs (eg positive pole). There is an oblique contact surface 2nd given for scanning for mechanically based tracking.
Next to it is a second contact area 3rd shown for power consumption by vehicle pantographs (negative pole). There is also a first supply line 4th (Positive pole) shown, which consists of stacked sheets.

There is also a supply line 5 (Ground potential or negative pole) consisting of stacked sheets is shown. In addition, there is a first central bridge 6a for improved dielectric strength between the two contact surfaces 1 , 3rd intended.

In addition there is a second central bridge 6b shown, which is designed to be exchangeable and designed for use in steering control.

There is also a gutter 7 for improved dielectric strength between the two contact surfaces 1 , 3rd shown. Next to it is a first data line 8th shown for the communication exchange between individual control units, in addition a second data line 9 (Network cable) as redundancy to the first data line 8th is executed.

There is also a fastening screw 10th , an asphalt dowel 11 , a steel plate 12th shown as carrier plate and housing potential (GND). Also is a first slide 13 or adhesive surface of the steel plate for maximum slip resistance between the underside of the conductor rail (sheet metal) and the road surface.

There is also a drainage canal 14 as a drain from itself in the channels 7 collecting water provided.

Next to it is a solid steel core 20 shown with a locking profile not described for exchangeability of the center bar in the event of wear or damage.

Next to it is an insulating surface 21 between the contact surfaces 1 , 2nd and a road surface 23 shown in the form of example asphalt pavement.

Next is a nose 22 , shown which snapped into place for easy replacement of worn contact surfaces 1 , 2nd through wear.

In this context is a second slide 24th or surface with high sliding friction. There is also a shield plate 25th shown, which in addition to electrical shielding also serves to improve the mechanical robustness of the busbar. For the sake of completeness, it is paved on a pavement 26 pointed out.

A first single sheet of metal 30th as an additional supply line and a second metal strip 32 is also in the 6 shown. There is between the two metal strips 30th , 32 a short distance 31 intended.

It also clicks on an area of the fold 33 in the transition of the first metal strip 30th in the second sheet metal strip above 32 pointed out.

Finally, a pantograph on the vehicle 40 and associated insulation 44 pointed out.

Lastly, a single-pole superconducting supply line 27 pointed out, which enables the distances between the entry points to feed electricity into the rail system to be significantly reduced. Thereby cooling units 50 used, which have a cylindrical housing shape and in the provided cylindrical installation spaces directly next to the busbar 50a , 50c be let into the lane.

Reference list

1

First contact area

2nd

Contact surface tracking

3rd

Second contact area

4th

First supply line

5

Second supply line

6

Mittelsteg

7

Gutter

8th

First data line

9

Second data line for redundancy

10th

Mounting screw

11

Asphalt dowels

12th

steel plate

13

First slide

14

Drainage canal

15

Track placed on the road

16

Conductor track embedded in roadway

17th

Track compatible to 16 in lane with continuous slot

18th

Power supply for contact area 1 , 3rd of the adjacent segments

20

Solid steel core

21

Insulating surface

22

nose

23

Road surface

24th

Track on roadway

25th

Shield plate

26

Road surface

27a

Superconductor line single-pole positive pole

27b

Superconductor single pole negative pole

28

Longitudinal slot in the track

29

Lateral insulation

30th

First sheet metal strip

31

distance

32

Second metal strip

33

Folding area

34

Liquid refrigerant for cooling

40

Pantograph

41

insulation

50

Cooling unit for superconductor cables

51

Flow direction of the refrigerant

52

Chiller with circulation pump

53

Shut-off device for redundancy

54

Superconductor section for a cooling circuit of 2 superconductors each

Claims (10)

Busbar for a roadway for the power supply of electrically operated motor vehicles, characterized in that the contact surfaces (1, 3) of this busbar are arranged next to one another and that they are separated by an insulating central web (6). Track after Claim 1 , characterized in that the voltage-free switchable contact surfaces (1, 3) have a detent-like shape Have profile shape or separate lugs (22) so that the contact surfaces (1, 3) can be replaced. Track after Claim 1 , characterized in that the depressions have drainage-like drainage channels (14) to the side of the central web (6). Track according to one of the Claims 1 to 3rd , characterized in that this busbar is applied to the road surface (23) or is slightly embedded in the road. Busbar according to one of the preceding claims, characterized in that the temperature of supply lines (4, 5) is measured and if the temperature is too high the supply current to the respective vehicles can be limited. Busbar according to one of the preceding claims, characterized in that sections of the busbar can be heated. Conductor rail characterized in that the supply lines (4, 5) consist of sheet metal strips (31, 32) stacked on top of one another for the purpose of maximizing current and robustness. Track after Claim 7 , characterized in that the individual sheet metal strips (31, 32) are in turn composed of a number of individual narrow sheet metal strips and that these sheet metal strips are joined or intertwined in such a way that the temperature-dependent change in length is compensated for. Conductor rail characterized in that the supply lines (27a, 27b) consist of a superconducting material for the purpose of maximizing current. Track after Claim 9 , characterized in that the cooling units 50 for cooling the superconductor are designed in a cylindrical shape and are embedded in the road and are driven over for the purpose of better heat dissipation.

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