DE102014220228A1 - Method for positioning a vehicle over an inductive power transmission system - Google Patents

Abstract

The invention relates to a method for positioning a vehicle by means of a control system over an inductive energy transmission system, wherein the control system comprises a source that generates an electromagnetic beam, wherein the vehicle has an environmental sensor, wherein in a first method step, the electromagnetic beam adaptive is guided and guided along a planned trajectory, in a second method step, the vehicle detects the electromagnetic beam continuously with the at least one environmental sensor and in a third process step the vehicle follows the planned trajectory and the planned trajectory departs.

Description

State of the art

Electric vehicles usually have an electrical energy storage, such as a traction battery that provides the electrical energy for propulsion. If this electrical energy store is completely or partially discharged, then the electric vehicle has to control a charging station, at which the energy store can be recharged. So far, it is customary for this purpose that the electric vehicle is connected to the charging station by means of a cable connection at such a charging station (so-called "conductive charging"). This connection must usually be made manually by a user. It is also necessary that charging station and electric vehicle have a mutually corresponding connection system.

There are also known wireless charging systems for electric vehicles. Instead of conductive charging, inductive charging represents an innovative solution for charging electric vehicles. In this charging process, no intervention by the vehicle user is necessary. The system is largely protected against the effects of the weather and, in contrast to conductive charging, is safe from vandalism. Typically, the electric vehicle for charging over a coil (primary coil or transmitting coil) is turned off. This coil is either embedded in the street floor or shaped as laid on the floor pallet. Furthermore, the primary coil is connected by means of suitable electronics to the power grid and emits a high-frequency alternating magnetic field during operation. The alternating magnetic field is picked up by a receiving coil (secondary coil). This secondary coil is typically fixedly mounted in the underbody of the vehicle and in turn is connected by suitable electronics to the vehicle battery. The high-frequency alternating magnetic field of the primary coil penetrates the secondary coil and induces there a corresponding current with which the vehicle battery is charged. The publication DE 10 2011 010 049 A1 discloses such a system for charging a vehicle battery, in which the energy is transmitted inductively.

Frequently, the receiving coils are in electric vehicles for reasons of improved crashworthiness and increased protection against the weather in the underbody of the vehicle. When wirelessly charging a battery of the electric vehicle is therefore located between the recessed in the bottom of a charging station transmitting coil of the charging station and the receiving coil in the vehicle, an air gap. Due to the required ground clearance of motor vehicles, this air gap is a few centimeters. Air gaps in the size of 15-25 cm are very common, unless an ideal small air gap is achieved by measures such as lowering the vehicle-fixed coil, the entire vehicle or lifting the stationary coil or a combination of these measures. Due to the strong magnetic fields, however, it is not desirable for objects such as contaminants or animals to be in the air gap during the charging process. Furthermore, there are important requirements for the positioning accuracy of the two coils. Since the efficiency of the energy transfer between the transmitting coil and the receiving coil depends strongly on the relative position of the (mobile) receiving coil in the vehicle with respect to the (stationarily mounted) transmitting coil in a charging station, the best possible or high coupling between the two coils must be achieved. This good coupling corresponds to a minimization of the electromagnetic stray field. The corresponding efficiency depends on the coupling factor of the coils with each other or on the size of the mentioned electromagnetic stray field. As the offset between the coils increases, the losses increase and the efficiency is reduced.

The publication WO 2012/058466 A1 discloses a coil positioning of a vehicle-mounted power transmission device by a mechanical positioning device in the base of the vehicle. The publication JP 2011 217 452 A discloses a positioning of receiver coils of an inductive power transmission device in the license plate area of vehicles. The publication CN 201 966 671 U discloses a positioning of receiver coils of an inductive power transmission device on the vehicle roof. The publication US 2012/0098483 A1 discloses a position determination and an automatic parking function using in-vehicle antennas for navigating the vehicle to a loading position with respect to an inductive power transmission device. The pamphlets DE 10 2010 053 058 A1 . JP 2012 005 308 . DE 10 2009 033 239 A1 and DE 10 2009 033 237 A1 each disclose additional positioning coils in vehicles to increase the positioning tolerance to inductive power transmission devices.

There is a need for precise and inexpensive inductive power transfer solutions which can improve the positioning of the transmit and receive coils relative to each other.

Disclosure of the invention

The inventive method for positioning a vehicle over a system for Inductive energy transmission with the characterizing part of claim 1 has the advantage that it is, inter alia, robust and maintenance-free. Furthermore, it is independent of weather conditions and possible pollution (eg the road) and cost feasible.

For this purpose, the invention provides that in the method for positioning the vehicle with a control system via an inductive energy transfer system, wherein the one guidance system has a source that generates an electromagnetic beam, wherein the vehicle has an environmental sensor, in a first method step ( A) the electromagnetic beam is directed adaptively and guided along a planned trajectory, in a second method step (B) the at least one vehicle continuously recognizes the at least one electromagnetic beam (or guide beam) with the at least one environmental sensor and in a third method step (C ) the at least one vehicle follows the planned trajectory and the planned trajectory departs. The vehicle to be charged is thus advantageously guided via the electromagnetic beam to the correct position, whereby a very low positioning tolerance (<10 cm) between the primary and secondary coil can be achieved. For this purpose, the control system, which contains the source that generates the electromagnetic beam, can be advantageously attached to any elevated positions in the parking space. The control system advantageously deflects the beam adaptively and can thus make corrections to the planned trajectory.

The measures mentioned in the dependent claims advantageous refinements of the method specified in the independent claim are possible.

Advantageously, the at least one electromagnetic beam is in the visible or in the infrared region of the electromagnetic spectrum. In the visible spectral range, the beam is visible to humans, so that it can see and track the light spot projected onto the road by the beam (spot or laser spot, etc.). If this is not desired, it is advantageous to choose a spectral range which is not visible to humans, e.g. the infrared spectral range.

In a further advantageous embodiment of the method, the electromagnetic beam is projected onto a travel path in front of the vehicle. From this projection of the beam results in a light spot or light spot on the road or the track, which can be detected with a built-in vehicle environment sensor. If the beam is deflected spatially, the projected light spot moves equally on the road or the track. The light spot is advantageously guided along a planned trajectory, which then follows the vehicle.

According to a further embodiment of the method, the electromagnetic beam is focused. The more focused the beam, the smaller the light spot projected on the driveway, and the more precisely the positioning of the vehicle can be made.

Furthermore, it is advantageous that the environmental sensor is a camera. With the camera operating either in the visible or infrared spectral range or in both spectral ranges, the beam projected onto the travel path can be registered. If the beam generated by the source is adaptively deflected and advantageously guided along a planned trajectory, the vehicle follows its trajectory by continuous detection by means of the camera and subsequent tracking of the beam.

In a further advantageous embodiment, the source is a laser. Lasers differ from alternative light sources advantageously by the otherwise unattainable combination of high intensity, very narrow frequency range (monochromatic light), sharp bundling of the beam and long coherence length. Also, with very wide frequency range, extremely short and intense beam pulses with exact repetition frequency are possible.

In a further advantageous embodiment, the steering of the at least one electromagnetic beam will be controlled on the assumption that the vehicle follows the laser spot on the track without interference. Alternatively, it may also be designed to be regulated on the at least one vehicle in order to preclude non-following the vehicle.

Advantageously, the electromagnetic beam is emitted coded by the at least one source. By coding, it is advantageously possible to perform the line multiple vehicles. To do this, the beam is varied in shape, frequency and / or modulation (e.g., flashing frequency).

Furthermore, the coding of the electromagnetic beam in a further advantageous embodiment relates to the form of the projection, the frequency or the modulation. Depending on the existing environmental condition or on request of the control of one or more vehicles advantageously the appropriate coding can be selected.

The control system is advantageously mounted on a position overlooking the entire parking space of the vehicle. The control system is mounted on a high mast above a free parking space, for example. This way will Ensures that the vehicle can be steered over the entire route and no obstacle or a non-visible route interrupts the guide beam and thus a steering of the vehicle is no longer possible. One or more control systems are thus mounted or mounted so that as few guide beams cover as large a share of a parking space consistently.

In a further advantageous embodiment, a plurality of guidance systems are coordinated by a superordinate guidance system and at least one vehicle is routed in sections. In the vehicle line can then be made in particular a section-wise guidance, in which the transitions of the sections, which are each covered by a guide beam. It is thus possible to steer the vehicle - even instead of steering it only in a straight line - around corners. Several guidance systems can be advantageously used if the parking space can not be covered or covered by a single system (for example within a parking garage) or if several vehicles have to be separately guided into the respective parking spaces and this has to be coordinated by a superordinate control system.

It is understood that the features mentioned above and those yet to be explained below can be used not only in the particular combination given, but also in other combinations or in isolation, without departing from the scope of the invention.

Brief description of the drawings

1 shows in schematic form a representation of the method according to the invention;

2 shows in schematic form a side view of a motor vehicle and a system positioning of the vehicle over an inductive power transmission system;

3 shows in schematic form a plan view of the motor vehicle and the system for positioning the vehicle over an inductive energy transmission system of 1 from above.

Embodiments of the invention

1 shows in schematic form a representation of the method according to the invention. For positioning at least one vehicle 10 with the help of at least one control system 14 in which the vehicle 10 is positioned over at least one system for inductive power transmission, the control system 14 at least one source 15 on that at least one electromagnetic beam 11 generated. The vehicle 10 also has at least one environment sensor 17 , In a first method step (A), the at least one electromagnetic beam 11 adaptively deflected and along a planned trajectory 12 guided. The beam 11 thus generates on the infrastructure 16 in front of the vehicle 10 a spot of light, the beam 11 (or the light spot) is continuously detected by the environment sensor in a second process step (B). In a third method step (C), the vehicle follows 10 the planned trajectory 12 and thus drives the planned trajectory 12 and thus optimally above the system for inductive energy transfer 13 positioned and can then be loaded.

2 shows a vehicle 10 that over an inductive charging system 13 or a system for inductive energy transfer 13 in a parking space 18 should be turned off. The vehicle 10 is turned off so that the secondary coil 20 or receiving coil 20 of the vehicle 10 above the primary coil 21 or transmitting coil 21 is arranged. Above the parking space 18 is at least one control system 14 mounted or mounted (eg as a fixed station). The control system 15 has a source 15 that has an electromagnetic beam 11 radiates. The source 15 is for example a light source or a laser and the electromagnetic beam (guide beam) 11 is preferably a laser beam 11 , The beam 11 is preferably focused and on the track 16 in front of the vehicle to be parked and loaded 10 projected. Depending on the position of the vehicle to be parked and loaded 10 is the resulting from the projection light spot or laser spot (not shown here) in the first process step (A) along a planned trajectory 12 guided and accordingly deflected adaptive. In the vehicle 10 is at least one environment sensor 17 arranged. This environment sensor 17 is for example a camera. The environment sensor 17 detected in the second step (B) the at least one electromagnetic beam 11 or on the track 16 projected light spot continuously. The vehicle 10 follows in process step (C) the light spot (or the beam 11 ) and is thus positioned above the inductive energy transfer system. The light spot or laser spot becomes on the guideway 16 at a distance to the vehicle 10 projected, so he from the in the vehicle 10 located environment sensor (camera) can be reliably detected. The electromagnetic beam 11 or light spot can be visible to humans (wavelength from the spectral range of the visual spectrum) or invisible (wavelength from the spectral range of the infrared spectrum). The control system 14 can either be controlled, assuming that the vehicle 10 the laser beam or light spot follows without interference. This is the vehicle 10 from the control system 14 continuously detected. On the other hand, that can Control System 14 on the vehicle 10 operated in order to rule out a failure to follow the vehicle. If several vehicles 10 by means of the control system 14 to steer, the control system encodes the beam 11 , For example, the shape (spot size, etc.), the frequency or the modulation of the beam is varied and thus the vehicle to be steered or conductive 10 individually assigned. Preferably, the control system 14 so above the parking space 18 attached that from the control system 14 can be completely overlooked or the control system 14 the parking space 18 completely covers. For example, the control system 14 on a high mast above the parking space 17 or a free parking space within the parking space 18 to be assembled. Is the full coverage of the parking space 18 through a single control system 15 Due to the parking space geometry not possible, several control systems 14 (at least two) mounted so that as few guide beams 11 the parking space 18 cover completely and consistently. In the vehicle line of the vehicle 10 is with several guidance systems 14 then a section-wise leadership possible, in which a control system 14 the vehicle 10 over a first section leads and another guidance system 14 ' (not shown here) the vehicle 10 then takes over and leads or steers over a second section. The various control systems can communicate with each other or be from a higher-level control system 19 coordinated. Several control systems 14 are used when multiple vehicles 10 in a parking space 18 to be guided or steered with several parking spaces. The coordination of the different control systems 14 . 14 ' , ... takes place either between each other and is controlled by a higher-level control system 19 performed.

3 shows in schematic form a plan view of the embodiment 2 from above. Same elements in terms of 1 are provided with the same reference numerals and are not explained in detail.

QUOTES INCLUDE IN THE DESCRIPTION

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

Cited patent literature

• DE 102011010049 A1 [0002]
• WO 2012/058466 A1 [0004]
• JP 2011217452 A [0004]
• CN 201966671 U [0004]
• US 2012/0098483 A1 [0004]
• DE 102010053058 A1 [0004]
• JP 2012005308 [0004]
• DE 102009033239 A1 [0004]
• DE 102009033237 A1 [0004]

Claims (11)

Method for positioning at least one vehicle ( 10 ) with at least one control system ( 14 ) via at least one inductive energy transmission system ( 13 ), wherein the at least one control system ( 14 ) at least one source ( 15 ) having at least one electromagnetic beam ( 11 ), wherein the at least one vehicle ( 10 ) via at least one environment sensor ( 17 ), characterized in that - in a first method step (A) the at least one electromagnetic beam ( 11 ) is guided adaptively and along a planned trajectory ( 12 ), - in a second method step (B) the at least one vehicle ( 10 ) the at least one electromagnetic beam ( 11 ) continuously with the at least one environment sensor ( 17 ) and - in a third method step (C) the at least one vehicle ( 10 ) of the planned trajectory ( 12 ) and the planned trajectory ( 12 ) leaves. Method according to claim 1, characterized in that the at least one electromagnetic beam ( 11 ) is in the visible or in the infrared region of the electromagnetic spectrum. Method according to one of the preceding claims, characterized in that the at least one electromagnetic beam ( 11 ) on a track ( 16 ) in front of the at least one vehicle ( 10 ) is projected. Method according to one of the preceding claims, characterized in that the at least one electromagnetic beam ( 11 ) is focused. Method according to one of the preceding claims, characterized in that the at least one environment sensor ( 17 ) is a camera. Method according to one of the preceding claims, characterized in that the at least one source ( 15 ) is a laser. Method according to one of the preceding claims, characterized in that the steering of the at least one electromagnetic beam ( 11 ) or on the at least one vehicle ( 10 ) is carried out in a regulated manner. Method according to one of the preceding claims, characterized in that the at least one electromagnetic beam ( 11 ) from the at least one source ( 15 ) is emitted coded. Method according to one of the preceding claims, characterized in that the coding of the at least one electromagnetic beam ( 11 ) the shape of the projection, the frequency or the modulation of the at least one electromagnetic beam ( 11 ). Method according to one of the preceding claims, characterized in that the at least one control system ( 14 ) on one the entire parking space ( 18 ) of the at least one vehicle ( 10 ) surveyed position is appropriate. Method according to one of the preceding claims, characterized in that a plurality of guidance systems ( 14 ) from a higher-level control system ( 19 ) and at least one vehicle ( 10 ) in sections.

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