DE102010042395A1 - Method for inductive charging of battery in vehicle e.g. electric car, involves performing the inductive coupling of primary coil in loading station and secondary coil of vehicle while maintaining preset gap between coils - Google Patents

Abstract

The method involves placing secondary coil (L2) of the vehicle (2) adjacent to primary coil (L1) of loading station (1). The inductive coupling of primary coil in loading station and secondary coil of the vehicle is performed while maintaining preset gap between the primary coil and secondary coil. An independent claim is included for system for inductive charging of battery in vehicle.

Description

The present invention relates to methods and systems for inductively charging a battery of a vehicle, such as. B. the traction battery of a road vehicle, which is equipped with an electric drive (eg., Electric car or "plug-in hybrid").

Unlike in a conventional shop in which the provided with the battery to be charged vehicle is connected via a cable and a plug connection to a power supply or a charging station, carried out during inductive charging, the transmission of electrical energy wirelessly via an inductive coupling of a primary coil Charging station with a secondary coil of the vehicle.

A system for inductively charging a vehicle battery includes a primary-side subsystem having the primary coil and a secondary-side subsystem having the secondary coil.

After placing the two coils in a specific arrangement suitable for the inductive coupling, the charging of the battery can be effected by energizing the primary coil in the primary-side subsystem. The induced thereby in the secondary coil of the secondary-side subsystem AC voltage can then z. B. rectified by means of a charging control device of the secondary-side subsystem and used to feed a direct current (charging current) into the battery.

The inductive charging of a vehicle battery has a number of advantages, such as above all an increased safety for the user, since there are no exposed electrical contacts and no special danger in moisture, unlike an electrical connector. Since the user does not have to manually create an electrical connector, resulting in a high comfort for the user. In particular, if the primary coil provided as a component of a (stationary) charging station and the secondary coil is permanently installed in the vehicle, there is no cumbersome handling with a charging cable, which in turn can be avoided by cable break failures. Finally, the facilities required for inductive charging on the vehicle and on the charging station can be easily secured against vandalism.

However, there are also disadvantages or problems to be considered, such. B. more or less large energy losses and any occurring "electrosmog". In inductive charging, energy is transferred from the primary coil mostly via an "air gap" to the secondary coil (air transformer). The quality of the inductive coupling of the two coils, d. H. the efficiency or the efficiency of the energy transfer depends strongly on the mutual arrangement (position and orientation) of the two coils and in particular the size of the remaining air gap therebetween.

In order to avoid excessive energy losses during inductive charging, a precise positioning and orientation of the two coils should therefore be ensured as part of commissioning the primary coil for inductive charging, in which the inductive coupling is guaranteed with a high degree of coupling and low wastage.

In the first inductively charged electric cars, a so-called "paddle" (housed primary coil) connected to a primary side power supply of a charging station and including the primary coil was used. By manually inserting this paddle into a dedicated (suitable) "paddle" receptacle provided for this purpose on the vehicle, which contains the secondary coil, the desired mutual arrangement of the primary coil and the secondary coil (exactly coaxial to one another and with minimal air gap) was thus ensured by a positive connection ,

However, a disadvantage to the user in this known solution is the expense of manually inserting the primary coil unit (paddle) of the primary-side subsystem into the associated receptacle of the secondary-side subsystem (vehicle).

It is an object of the present invention to enable a high energy transfer efficiency with simultaneous high convenience for the user in the case of inductive charging of a vehicle battery.

This object is achieved according to the invention by methods and systems or subsystems, which are specified in the independent claims. Advantageous developments of the invention will become apparent in particular by any combination of the independent claims with each other and / or by adding features that are specified in the dependent claims.

According to the invention, an automatic placement of the primary coil and / or the secondary coil to achieve a specific mutual arrangement of the primary coil and the secondary coil. intended.

This can reliably high quality inductive coupling with low losses in the Charging and at the same time a high ease of use for the user to be ensured.

Accordingly, in a method for operating a primary coil or in a primary-side subsystem, for example, the primary coil can be placed, i. H. relative to a (usually stationary) installation location of the charging station to be moved.

Alternatively or additionally, in a method for operating a secondary coil or in a secondary-side subsystem, the secondary coil can also be placed, i. H. For example, be moved relative to a vehicle chassis. As an alternative or in addition to a movement of the secondary coil relative to the vehicle chassis, in the context of the invention for the same purpose it is also possible to move the vehicle itself.

To accomplish the automatic placement of the primary coil and / or the secondary coil, the primary-side subsystem or the secondary-side subsystem can be equipped with controllable adjustment means.

The adjustment can z. B. one or more controllable actuators (eg., Electromotive actuators) include, which are controlled by a control device and mechanically connected to the primary coil or secondary coil or their housings to a desired movement (translational and / or rotational) of the effect coil in the context of automatic placement.

The control means used to drive the adjusting means may e.g. B. by an electronic, program-controlled control device (eg, containing a microcontroller) may be formed. It can be arranged on the primary side and / or secondary side and z. B. based on primary and / or secondary side acquired acquisition variables (in particular, for example, sensor signals) according to a setting algorithm generate the corresponding drive signals for the adjustment.

A sensor signal used by the controller may, for. B. representative of the instantaneous arrangement (translational and / or rotational) of the primary coil or the secondary coil (or of the vehicle).

In this context, it should be noted that the control device or that part of the control device which generates a drive signal for an actuator, taking into account a sensor signal obtained by means of a sensor, by no means necessarily together with the sensor and the actuator "on the same side" (primary side or secondary side ) must be arranged. Rather, a transmission of a sensor signal or of sensor data and / or a transmission of a control signal or of control data from the primary side to the secondary side and / or vice versa may optionally be provided. Apart from a data transfer z. B. by radio results in a particularly advantageous possibility for data transmission through the already existing inductive coupling between the primary coil and secondary coil. As explained below, the inductive coupling before and / or during the actual energy transfer (for charging the battery) can also be advantageously used for data transmission.

According to one embodiment of the automatic placement, this includes a controlled movement of the relevant coil (s), each coil z. B. can be moved in a direction parallel to its coil axis. Alternatively or additionally, the coil can also be moved in at least one direction transversely, in particular orthogonal to its coil axis. In addition, alternatively or additionally, a movement that rotates or swivels the coil (by one or more axes) may finally also be provided.

In an embodiment of the automatic placement, a quality of the inductive coupling is detected and the automatic placement is performed as a function of the detected coupling quality. In this case, the quality of the inductive coupling serves as a sensor signal to be used by the control means for driving the adjusting means. The "quality" of the inductive coupling can be a detection quantity determined on the basis of electrical measured variables, which represents a measure of the energy transmission efficiency of the inductive coupling. As detection size is well suited z. B. in particular the secondary-side power or voltage at a given, predetermined primary-side energization of the primary coil. In a particularly advantageous development, the control device is designed to implement a control algorithm for implementing an "optimization strategy", with the aim of bringing the primary coil and the secondary coil into a mutual arrangement in which the energy transmission efficiency is relatively large or optimized.

According to one embodiment of such an optimization method, it is provided, for example, that the instantaneous quality of the inductive coupling is first measured in a first step starting from a specific setting of all the actuators, then a small change of at least one actuator setting is made in a second step (eg. a random change), in a third step the coupling quality is measured again and in a fourth step Step is determined whether the coupling quality has improved or deteriorated by the change, wherein in case of improvement, the processing immediately goes back to the first step, whereas in case of deterioration first in a fifth step, the last change of the setting is reversed and only then returned to the first step. In this or similar ways, the automatic placement can be done to a certain extent by controlling the coupling quality to a maximum.

According to one embodiment of the automatic placement of the secondary coil, the latter comprises an automatic maneuvering of the vehicle to achieve the specific mutual arrangement of the primary coil and the secondary coil (ie in particular, for example, with regard to the coupling quality). In a further development, the vehicle is a road vehicle with a motor, in particular an electric drive and a motor, in particular electric steering (eg electric car or plug-in hybrid). In this case, the automatic maneuvering by suitable driving the z. B. electric drive, preferably in conjunction with a suitable control of z. B. electrical steering. For the purpose of realizing the above-described optimization strategy, the drive of the vehicle and / or the steering of the vehicle are then to be regarded as special actuators (for moving the secondary coil).

• – Überprüfen, ob sich die Sekundärspule in der Nähe der Primärspule befindet oder nicht,
• – sobald die Sekundärspule in der Nähe der Primärspule festgestellt wurde, Initiierung einer Bestromung der Primärspule zum induktiven Laden der Batterie.

In a preferred embodiment of the invention, the following steps are carried out to start up the primary coil for inductive charging:

• Check whether the secondary coil is close to the primary coil or not,
• - Once the secondary coil has been detected in the vicinity of the primary coil, initiation of energization of the primary coil for inductive charging of the battery.

Such a start-up of the primary coil can be provided as a development of the method according to the invention for operating a primary coil in a primary-side subsystem or overall system according to the invention, although it should not be ruled out that in the said checking step and / or said step of initiating the energization Participation takes place by the secondary-side subsystem or the secondary-side subsystem has a special design suitable for this purpose.

In the simplest case, the above-mentioned commissioning of the primary coil essentially takes place only by system components arranged on the primary side. To realize the verification step z. B. on the primary side at least one sensor for detecting a nearby secondary coil (or a vehicle) may be provided, for example, a photoelectric sensor, a contact switch, a load sensor (for detecting a vehicle based on the vehicle weight) etc. Once by means of such a sensor, the presence of a Vehicle (with the secondary coil) has been determined, z. B. initiation of the energization of the primary coil take place such that it is acted upon by an alternating current of, for example, initially fixed frequency and amplitude.

Automatic commissioning of the primary coil for inductive charging in this way represents a high degree of operating comfort, in particular, when the user (eg vehicle operator) does not first have to undertake a manual operating action for switching on the primary-side supply field.

• – schwache Bestromung der Primärspule,
• – Messung der primärseitigen und/oder sekundärseitigen Leistungsaufnahme.

However, a sensor specially arranged in the system for the checking step is not absolutely necessary for the commissioning explained above. According to an advantageous embodiment, it is provided that the checking is accomplished simply by measuring an electrical load in the inductive coupling, so z. B. comprises the following steps:

• - weak energization of the primary coil,
• - Measurement of the primary-side and / or secondary-side power consumption.

This development uses the fact that in the case of the presence of the secondary coil from a certain proximity to the primary coil already an inductive coupling between the two coils, so that z. B. by a measurement of the primary side power consumption, the presence of the secondary coil can be easily detected (The primary load current or the primary power (ability) increases in height extremely strong as soon as a "power take" (secondary coil) in the generated by the primary coil Such an increase in power or power, typically by one or more powers of ten (in comparison to a "quiescent current" without a secondary coil located in the vicinity) can easily be detected by a corresponding threshold value overshoot.

In the "test run" of the primary coil with the weak energization z. B. a primary current can be used which is smaller by at least a factor of 10 ² , preferably at least a factor of 10 ³ as intended for the actual inductive charging rated current.

The weak energization can from the primary-side subsystem z. B. independently at certain intervals (eg, each about 1 second long, at intervals of about 1 minute) are performed. If in such a test run a characteristic of the presence of the secondary coil power consumption is measured, so in the simplest case, an initiation of the energization of the primary coil without further intermediate steps take place in such a way that z. As already mentioned above, the primary coil is supplied with an alternating current of at least initially predetermined frequency and amplitude.

The mentioned, preferably performed with drastically reduced power "test run" of the primary coil advantageously avoids electromagnetic interference, energy losses and beyond possible damage z. B. in nearby cardiac pacemakers by a constantly "radiant" primary coil. According to the embodiment explained above, the magnetic field generator (primary coil) is put into operation with higher power only when the associated pickup, in this case the vehicle equipped with the secondary coil, is in the field.

On the other hand, it is problematic to switch to the actual charging operation, when inadvertently a "secondary coil-like" object is in the magnetic field of the primary coil, such. As a bicycle, which can trigger the energization of the primary coil with the power provided for inductive charging current. To eliminate this problem, a data transmission between primary-side subsystem and secondary-side subsystem is provided according to an embodiment of the invention, by means of which such erroneous startup of the primary coil for inductive charging is avoided. According to a particularly advantageous realization, provision is made for data transmission via the inductive coupling from the primary-side subsystem to the secondary-side subsystem and / or vice versa during commissioning of the primary coil for inductive charging and / or during operation of the primary coil for inductive charging (eg by requesting an "identification") z. B. a bicycle or a non-loading vehicle or other object can be recognized as "not suitable for loading object". In this embodiment, the already existing inductive coupling is advantageously used for data transmission.

In the simplest case, z. Example, the secondary coil or the associated vehicle identifying information and / or other "state parameters" of the secondary-side subsystem (eg., Battery type, battery charge status, etc.) similar to an RFID (radio frequency identification) method from the secondary side to the primary side be transmitted. In this comparison with an RFID system, the primary-side subsystem forms a sort of "RFID reader" and the secondary-side subsystem an "RFID transponder", from which information (here: identification) is read out by means of the primary-side subsystem.

By such a data transmission, in which a secondary side subsystem identifying information and / or another, but previously set in the overall system or agreed information is transmitted, z. B. reliably prevent erroneous commissioning of the primary coil for inductive charging, the z. B. could be triggered by an approach of a secondary coil similar object otherwise.

According to a preferred embodiment of the above-described start-up of the primary coil, it is provided that, in the context of checking whether the secondary coil is in the vicinity of the primary coil or not, the secondary-side subsystem transmits an identification (eg numerical code to the primary-side subsystem, Whereupon the initiation of the energization of the primary coil for inductive charging takes place only after the transmission of a "correct" or valid identification, in which case the inductive coupling is preferably used for the data transmission.

According to a further development, it is provided that the data transmission takes place alternately between the primary-side subsystem and the secondary-side subsystem and, as a result, at least one parameter of the inductive charging is determined. Such two-way communication between the two subsystems allows for a variety of other interesting designs.

For example, the primary-end subsystem can thus transmit information (eg code) identifying this subsystem and / or further information characterizing the properties of the primary-side subsystem to the secondary-side subsystem (eg information about the "charging station type", technical specifications) the charging station, via operating parameters available on the primary side for the inductive charging (eg primary current frequency, primary field power, etc.) Alternatively or additionally, the primary-side subsystem could transmit information about the current electricity price to the vehicle provided by the user in the case of carrying out the battery charging is to be paid.

Also z. B. information or data from the primary side to the secondary side are transmitted, which in no immediate connection with the inductive charging the Vehicle battery stand. These may be, for example, image files (eg newspapers or magazines), audio files (eg music files or so-called "podcasts", eg in MP3 format or the like), video files (eg messages , Films, etc.) act.

According to a development, the primary-side subsystem has a billing system or is connected to such a billing system, which billing data for billing the cost of battery charging (electricity costs) and / or parking fees and / or costs of transferring data or files of the type mentioned ( Image, audio, video, etc.) to the user after the battery charging process is completed.

With regard to the technical realization of a data transmission via the inductive coupling from the primary-side subsystem to the secondary-side subsystem and / or vice versa, it is provided according to one embodiment that the system energization control means for enabling a variation of at least one parameter of the energization of the primary coil and / or load control means to enable Variation of at least one parameter of the power consumption of the secondary coil comprises.

Due to the variation in the primary-side subsystem of at least one lighting parameter (eg frequency and / or amplitude of the primary current), be it the above-mentioned "test run" of the primary coil with weak energization or in the "normal" operating mode for charging the battery this data transmission from the primary side to the secondary side take place.

For this purpose, the secondary-side subsystem merely has to be equipped with suitable demodulation means in order to recover the relevant information from the voltage induced in the secondary coil.

The data transmission in the reverse direction, ie from the secondary side to the primary side could be realized in a corresponding manner, d. H. by an (active) energization of the secondary coil in accordance with a predetermined modulation for the coding of information, in which case corresponding demodulation means must again be present on the primary side. According to a preferred variant, however, the secondary-side modulation is carried out with the aforementioned load control means of the secondary-side subsystem, so that advantageously no "active power supply" on the secondary side is necessary for this modulation. Demodulation means required on the primary side can advantageously be at least partially identical to the already mentioned detection means for detecting the quality of the inductive coupling, with which the primary-side power consumption is measured and evaluated. A measurement of the primary-side power consumption of the primary coil carried out by the primary-side subsystem can be used on the one hand for checking for the presence of a secondary coil, and on the other as a basis for demodulating the information transmitted by such a secondary coil.

The invention will be further described by means of embodiments with reference to the accompanying drawings. They show:

1 a system for inductively charging a battery of a vehicle according to an embodiment,

2 a block diagram of some components of the system of 1 .

3 a flow chart of a in the system of 1 applicable optimization method, and

4 a flow chart of a in the system of 1 applicable overall process.

1 illustrates a system 10 for inductively charging a battery BAT of a vehicle 2 by means of an inductive coupling of a primary coil L1 of a charging station 1 (Which forms a "primary-side subsystem") with a secondary coil L2 of the vehicle 2 (which forms a "secondary-sided subsystem").

In the vehicle 2 In the example shown, this is an electric car, comprising an electric drive MA and an electric steering ML, which are in operation of the vehicle 2 from the battery BAT (traction battery) via a vehicle control unit 12 be energized. The control unit 12 For this purpose, as shown, it is connected to both the battery BAT and the drive units MA and ML. Corresponding control signals are in 1 symbolized with sml and sma.

For simplicity of illustration, in 1 shown only for understanding the invention described below relevant components. In particular, only components required for normal driving operation (eg accelerator pedal, etc.) are well known in the art and in 1 not shown.

In the illustrated embodiment, the secondary coil L2 in a coil housing G2 in the region of a floor of the vehicle 2 arranged with vertically oriented coil axis and the primary coil L1 in a coil housing G1 with also vertically oriented coil axis in the region of Base area (eg ground) of the charging station 1 arranged.

The inductive coupling of the primary coil L1 and the secondary coil L2 results when, as in 1 represented the vehicle 2 like that at the charging station 1 is turned off that the two coils L1 and L2 are arranged adjacent to each other with not too great a distance. In this situation, an inductive charging of the battery BAT can be accomplished by the charging station 1 For this purpose, the primary coil L1 is put into operation by energizing it with an alternating current I1, so that the voltage induced thereby in the secondary coil L2 leads to a current flow symbolized by I2, which is emitted by the vehicle control unit 12 can be forwarded as a charging current for the battery BAT after rectification.

A special feature of the charging station 1 formed primary-side subsystem is that this "primary-side adjustment" for automatically placing the primary coil L1 to achieve a specific mutual arrangement of the two coils L1 and L2.

This is advantageously possible that after parking the vehicle 2 a good quality of the inductive coupling for the described charging process can be achieved even if the vehicle 2 "Inaccurate" at the charging station 1 was placed.

In the illustrated example, the primary-side adjusting means comprise electrically controllable actuators Ax1, Ay1 and Az1, which are each connected to the coil housing G1, so that this housing G1 together with the primary coil L1 housed therein in each of the three spatial directions x (longitudinal), y (transverse direction) and z (vertical direction) relative to the base surface of the charging station 1 can be moved. The actuation of the actuators takes place by means of corresponding control signals sx1, sy1 and sz1, which are generated by a control unit 14 the charging station 1 for effecting the automatic placement of the primary coil L1. For the sake of clarity, the illustration is in 1 the actuator Ay1 not shown, together with its control.

This design of the charging station 1 with adjustable primary coil L1 has a great advantage in particular when the secondary coil of the vehicle to be loaded is attached to a fixed position (immovable) on this vehicle. A possible "misalignment" of the vehicle can then be compensated advantageous by the automatic placement of the primary coil L1.

That of the in 1 illustrated vehicle 2 However formed secondary subsystem also has a special feature in that it is equipped with "secondary side adjustment" for automatically placing the secondary coil L2, which allow the achievement of a specific mutual arrangement of the primary coil and the secondary coil.

In the illustrated embodiment, these secondary-side adjusting means include electrically controllable actuators Ax2, Ay2 and Az2, which are each connected to the secondary coil L2 containing coil housing G2 to this housing G2 together with the secondary coil L2 in the three spatial directions x, y and z (relative to a on-board coordinate system) during automatic placement. For the sake of clarity, the illustration is in 1 the actuator Ay2 not shown, together with its control.

Apart from in the illustrated embodiment thus created further adjustment with respect to an optimal mutual arrangement of the two coils L1 and L2 has the vehicle 2 especially a great advantage, if different from the in 1 illustrated situation, the primary-side subsystem (charging station) provides no adjustability for the primary coil. Even then, a possible malposition of the vehicle 2 be compensated advantageously on the relevant base surface by a suitable adjustment of the secondary coil L2 with respect to the vehicle chassis.

In this context, it should be noted that the charging station shown 1 also with other than the vehicle shown 2 can be used and the vehicle shown 2 also with other than the illustrated charging station 1 can be used. However, it is advantageous if in the "overall system" certain design details of the charging station 1 on the one hand and the vehicle 2 on the other hand are coordinated. In the example shown, such a design detail is, for example, the orientation of the primary coil L1 with a vertical coil axis relative to the charging station 1 and the corresponding orientation of the secondary coil L2 with also vertical coil axis with respect to the vehicle 2 , In the illustrated system, this makes additional actuators for a rotary movement (pivoting) at least the primary coil L1 or the secondary coil L2 unnecessary. Further advantageous in the two subsystems 1 and 2 design details that can be coordinated relate to the way in which information or data can be transmitted or exchanged between these subsystems and how the vehicle control unit 12 and / or from the charging station control unit 14 used to automatically place the coil (s) L1 and / or L2 " Setting algorithm "concrete runs. These aspects will be described in more detail below.

In a method for operating the primary coil L1 in the primary-side subsystem (charging station 1 ) or in the overall system (charging station 1 in cooperation with the vehicle 2 ) for inductively charging the battery BAT of the vehicle 2 by means of the inductive coupling between the two coils L1 and L2, an automatic placement of the primary coil L1 is provided so that in particular z. B. to optimize the coupling quality optimized mutual arrangement of the coils L1 and L2.

In a method for operating the secondary coil L2, automatic placement of the secondary coil L2 can be provided in a corresponding manner.

For this purpose usable primary-side and / or secondary-side adjustment means have already been explained above.

As regards the manner of automatically placing the primary coil L1 and / or secondary coil L2, it is provided according to an advantageous embodiment that a (instantaneous) quality of the inductive coupling between the coils L1 and L2 is detected and the coil L1 and / or the coil L2 is automatically placed depending on the detected coupling quality. To realize the relevant actuators by means of the vehicle control unit 12 and / or the control unit 14 be suitably controlled according to a "setting strategy".

3 exemplifies a procedural realization (algorithm) of such a setting strategy, by a control device (here: control unit 12 and / or control unit 14 ) can be carried out.

In a step S1, the instantaneous quality of the inductive coupling is measured. Then, in a step S2, a change, for. B. made a small and random change at least one Aktoreinstellung to again measure the coupling quality in a further step S3. If it is determined in a step S4 that the coupling quality has improved by the change, the processing returns to step S1. In the case of a deterioration, the change is reversed first in a step S5 and only then returned to step S1. By means of such an algorithm, the actuators Ax1, Ay1, Az1, Ax2, Ay2 and Az2 available in the illustrated example can be controlled in such a way that the best possible inductive coupling results in avoiding leakage losses during inductive charging.

If both the charging station as shown 1 as well as the vehicle 2 provides an adjustability of the respective coupling coil L1 and L2, it must be ensured only by a suitable communication between the two subsystems that a coordinated adjustment of the primary coil L1 and the secondary coil L2 takes place. It is clear that on the basis of such communication there are a large number of possibilities for suitably providing the adjustment of one of the two coils L1 and L2 in the case of adjustability of the respective other coil (L2 or L1). In the example shown, a coordination z. B. be realized by after parking the vehicle 2 First, the primary coil L1 is set for a possible improvement of the coupling quality, while for this time the secondary coil L2 is not adjusted. Then could be done for any further improvement in the coupling quality setting of the secondary coil L2, while the primary coil L1 rests. Then these two processes could also be repeated one or more times.

The direct control of the primary coil L1 is carried out by the control unit 14 whereas the immediate control of the secondary coil L2 by the control unit 12 he follows. However, after appropriately a communication or data transmission between these control components 12 and 14 It is by no means imperative that the generation of the drive signals sx1, sy1, etc. (for the coil L1) is completely autonomous by the control unit 14 and / or the generation of the drive signals sx2, sy2, etc. (for the coil L2) completely autonomously by the control unit 12 is carried out. On the basis of the mentioned communication can z. B. readily an already coordinated generation of drive signals for both coils L1 and L2 alone by the control unit 14 (alternatively alone by the controller 12 ), whereby the drive signals required for "the other side" can be communicated to the same.

Incidentally, is different from the illustrated embodiment of the vehicle 2 An adjustability of the secondary coil L2 for optimizing the inductive coupling can also be realized by carrying out an automatic actuation of the vehicle drive MA and of the vehicle steering system ML, ie the vehicle, instead of activating the vehicle-side actuators Ax2 and Ay2 2 automatically on the base of the charging station 1 is ranked. In this case, the actuators Ax2 and Ay2 are dispensable. In the setting strategy explained above (cf. 3 ) can be used to maneuver the vehicle 2 available components MA and ML are considered or used accordingly.

At the in 1 shown system could z. B. the following procedure take place:
The charging station 1 energizes the primary coil L1 at periodic intervals (eg, every 10 to 20 seconds) for a certain amount of time (eg, about 1 second) with a relatively small "test current" I1 (eg, fixed current AC current and small amplitude).

If now the vehicle 2 by a user like in 1 shown at the charging station 1 is turned off, the secondary coil L2 enters the outgoing from the primary coil L1 field (magnetic field). This circumstance is due to the charging station 1 detected on the basis of the associated increase in the primary-side power consumption of the primary coil L1. For this purpose suitable evaluation, z. B. comprising a measuring device for measuring the primary current I1 at a predetermined loading of the primary coil L1, are in 1 not shown. However, numerous well-known options are available to the person skilled in the art for their realization.

After so in this way the presence of an object or the vehicle 2 was detected, the charging station begins 1 as part of the commissioning of the primary coil L1 first a "transmission" of various information, for which a according to a previously defined "transmission protocol" modulated primary current I1 is generated, which may still have a relatively small amplitude in this data transfer phase. The information sent is z. B. to one or more of the following information: identification of the electricity supplier or operator of the charging station 1 , Identification (eg type) of the charging station 1 and available "charging operating parameters" (eg, possible frequencies and strengths of the primary field) of the charging station 1 , current electricity price, available "multimedia offer" (eg in an entertainment system of the vehicle 2 recordable MP3 files) etc.

At the same time and / or immediately after sending this information, the charging station expects 1 an "answer", in turn, from the vehicle 2 via the inductive coupling (coils L2 and L1) to the charging station 1 is transmitted. This can be z. B. by an active energization of the secondary coil L2 according to the agreed transmission protocol or alternatively z. B. by a secondary-side "load modulation" done in which in the vehicle 2 is varied by the secondary coil L2 energized load. In the latter case, the vehicle works 2 comparable to a "passive RFID transponder".

With such a mutual data transmission between the primary-side subsystem 1 and the secondary-side subsystem 2 Advantageously, it is possible to realize a type of "handshake" method in which, after a detection of the presence of a secondary coil L2 during the initial operation of the primary coil L1 for inductive charging, there is no immediate energization with the (high) primary current intensity provided for charging the battery BAT takes place, but first by the query of information from the secondary-side subsystem possible mis-commissioning can be avoided (and preferably also operating parameters of the actual charging process to be agreed).

2 illustrates the principal function of the secondary-side subsystem (vehicle 2 ) in the aforementioned retransmission of information to the charging station 1 ,

As in 2 can be seen, includes the vehicle control unit 12 a charging control unit 16 , which is supplied via a coupling capacitor C with the voltage indicated in the secondary coil L2 voltage U2, so that after appropriate control of the charging control unit 16 by a control unit 18 the battery BAT can be charged. The two control units 16 and 18 stand for this purpose in a mutual communication connection, so that from the control unit 16 also z. B. information about the state of charge of the battery BAT to the control unit 18 can be transmitted.

Parallel to the charging control unit 16 is a communication unit 20 arranged, which thus also the voltage U2 is supplied via the coupling capacitor C.

The communication unit 20 It has two purposes: First, it acts as a "demodulator" to recover information encoded by the waveform of voltage U2 and to the control unit via a two-way communication link 18 pass. After in the control unit 18 then the corresponding response information generated and the same communication back to the communication unit 20 has been delivered, this communication unit serves 20 as a "modulator" in order, by a secondary-side load modulation, the response information (by means of the inductive coupling of the coils L1, L2) to the charging station 1 transferred to. This modulation is done by the control unit 18 driven.

Based on the answer information, the charging station 1 then in a corresponding manner (by evaluation of the primary-side power consumption) recover the response information and evaluate.

In particular, the answer information may include one or more of the following information: one the vehicle 2 and / or its user identifying information (eg, numeric code), information about a desired primary field strength or range for the primary field strength, other loading parameters such. B. a desired charging time, etc. In addition, by the response information z. B. one on controls of the vehicle 2 User-initiated request for the transmission of multimedia files etc. done.

With regard to an authentication of the vehicle 2 or by its user can in the mutual data transfer between charging station 1 and vehicle 2 Advantageously, encryption methods are used to avoid "listening" of the transmitted data. The charging station 1 may in particular be provided in a network of publicly accessible charging stations.

The information transmitted via the "interface" of the inductive coupling between the coils L1 and L2 advantageously also allow the unambiguous assignment of the electricity costs, so that after completion of the actual charging process also essential steps for the settlement of electricity costs from the charging station 1 or their control unit 14 can be done, in particular the calculation of electricity costs and assignment to a specific user.

The actual charging of the battery BAT begins only after completion of the described mutual exchange of information as well as the above-explained setting of the primary coil L1 and / or the secondary coil L2 to optimize the inductive coupling. During the actual charging process, the primary coil L1 is operated with a significantly increased current intensity I1 compared to the mentioned "test run" or the mentioned data exchange.

The communication between the charging station before the actual charging process 1 and vehicle 2 and / or the adjustment of the inductive coupling to the highest possible transmission efficiency (by moving the primary coil L1 and / or the secondary coil L2) can be easily repeated even later, ie during the actual charging process.

If z. B. during charging of the battery BAT shows that the charge will be completed sooner than expected, so the vehicle 2 this circumstance over the described data transmission connection to the charging station 1 Report to finish charging sooner. Conversely, if it turns out during charging that the charging of the battery BAT takes longer than expected, this can be done by the vehicle 2 be requested later. The eventual intended transmission of multimedia files preferably takes place during the actual charging process.

4 again summarizes the steps of the exemplary procedure described procedure.

In a step S11, the check is made as to whether or not the secondary coil L2 is in the vicinity of the primary coil L1 ("test run"). If no secondary coil L2 is detected in step S12, the processing returns to step S11. If, however, the secondary coil L2 has been detected, the transmission of information or data from the charging station takes place in a step S13 1 to the vehicle 2 , and in a step S14 the transmission of the corresponding response information from the vehicle 2 to the charging station 1 , In a step S15, the charging station decides 1 based on the received response information on whether commissioning of the primary coil L1 for the inductive charging can or may not take place. If not, the processing proceeds to a step S17 at which the processing is finished. This is z. Example, the case when the user does not accept the electricity price transmitted in step S13, or if it turns out based on the transmitted in step S14 answer information that the vehicle 2 incompatible with the charging station 1 is.

Otherwise, the automatic adjustment of the primary coil L1 and / or the secondary coil L2 takes place in a step S16 (eg according to an optimization strategy as in FIG 3 by way of example), and the actual charging of the battery BAT by charging the primary coil L1 with the primary current strength intended for charging (for example, fixedly specified or else previously agreed by the data exchange in steps S13 and S14).

• – Höchster Komfort, ohne dass der Benutzer ein Ladekabel anstecken und eine Stromübertragung manuell einschalten muss.
• – Automatische, physikalisch optimale Ausrichtung des Fahrzeuges 2 im Feld der Ladestation 1, zur Erreichung des maximal möglichen Wirkungsgrades zur Verminderung der Verluste.
• – Kurzzeitiges ”Antesten”, ob sich ein Energieabnehmer (Fahrtzeug 2) im Feld befindet, mit vorteilhaft kleiner Sendeleistung.
• – Eindeutige Authentifizierung des Fahrzeuges 2 und/oder Benutzers mittels ein- oder wechselseitigem Codeabgleich über die induktive Kopplung.
• – Kleinstmögliche Elektrosmog-Belastung für die Umwelt.
• – Es können Fahrzeugdaten (z. B. Ladezustand der Batterie BAT) zurück in das Stromnetz bzw. die Ladestation kommuniziert werden, um beispielsweise die verbleibende Dauer des Ladens abwägen zu können.
• – Es können nach einer erfolgreichen Anmeldung an der Ladestation 1 während des meist langen Aufladens auf die gleiche Weise digitale Daten (z. B. MP3-Titel) ebenso drahtlos/magnetisch aus dem Stromnetz bezogen werden.

In summary, the described embodiments of methods and systems or subsystems for inductive charging of the vehicle battery BAT z. B. have the following advantages:

• - Maximum comfort without the user having to plug in a charging cable and switch on a power transmission manually.
• - Automatic, physically optimal alignment of the vehicle 2 in the field of the charging station 1 , to achieve the maximum possible efficiency to reduce losses.
• - Short-term "Antesten", if an energy consumer (Fahrzeug 2 ) is in the field, with advantageously low transmission power.
• - Unique authentication of the vehicle 2 and / or user by means of one or two-way code matching on the inductive coupling.
• - The smallest possible electrosmog pollution for the environment.
• Vehicle data (eg state of charge of the battery BAT) can be communicated back into the power grid or the charging station in order, for example, to be able to weigh the remaining duration of the charging.
• - It can after a successful login to the charging station 1 digital data (such as MP3 tracks) can also be obtained from the power grid wirelessly / magnetically in the same way during the usually long charging process.

Claims (15)

Method for operating a primary coil (L1) in a system ( 1 . 2 ) for inductively charging a battery (BAT) of a vehicle ( 2 ) by means of an inductive coupling of the primary coil (L1) of a charging station ( 1 ) with a secondary coil (L2) of the vehicle ( 2 ), characterized by automatically placing the primary coil (L1) to achieve a particular mutual arrangement of the primary coil (L1) and the secondary coil (L2). Method for operating a secondary coil (L2) in a system ( 1 . 2 ) for inductively charging a battery (BAT) of a vehicle ( 2 ) by means of an inductive coupling of a primary coil (L1) of a charging station ( 1 ) with the secondary coil (L2) of the vehicle ( 2 ), characterized by automatically placing the secondary coil (L2) to achieve a particular mutual arrangement of the primary coil (L1) and the secondary coil (L2). Method for operating a system ( 1 . 2 ) for inductively charging a battery (BAT) of a vehicle ( 2 ) by means of an inductive coupling of a primary coil (L1) of a charging station ( 1 ) with a secondary coil (L2) of the vehicle ( 2 ), characterized by an automatic placement of the primary coil (L1) and / or secondary coil (L2) to achieve a specific mutual arrangement of the primary coil (L1) and the secondary coil (L2). Method according to one of claims 1 to 3, comprising detecting a quality of the inductive coupling and an automatic placing depending on the detected coupling quality. Method according to one of claims 1 to 4, wherein the automatic placement of the primary coil (L1) and the secondary coil (L2) takes place in a direction (z) parallel to the coil axis and / or in at least one direction (x, y) orthogonal to the coil axis , Method according to one of claims 1 to 5, comprising an automatic maneuvering of the vehicle ( 2 ) to achieve the particular arrangement of the primary coil (L1) and the secondary coil (L2). Method according to one of claims 1 to 6, wherein the following steps are carried out for starting the primary coil (L1) for the inductive charging: Check whether the secondary coil (L2) is near the primary coil (L1) or not, - Once the secondary coil (L2) has been detected in the vicinity of the primary coil (L1), initiation of energization of the primary coil (L1) for inductive charging of the battery (BAT). The method of claim 7, wherein the checking comprises the steps of: Weak current supply to the primary coil (L1), - Measurement of the primary-side and / or secondary-side power consumption. Method according to one of claims 1 to 8, wherein during commissioning of the primary coil (L1) for the inductive charging and / or during operation of the primary coil (L1) for the inductive charging a data transmission via the inductive coupling from the primary-side subsystem ( 1 ) to the secondary-side subsystem ( 2 ) and / or vice versa. Method according to claim 9, wherein the data transmission alternately between the primary-side subsystem ( 1 ) and the secondary-side subsystem ( 2 ) and thereby at least one parameter of the inductive charging is determined. Primary subsystem ( 1 ) in a system ( 1 . 2 ) for inductively charging a battery (BAT) of a vehicle ( 2 ) by means of an inductive coupling of a primary coil (L1) of a charging station ( 1 ) with a secondary coil (L2) of the vehicle ( 2 ), characterized by primary-side setting means (Ax1, Ay1, Az1) for automatically placing the primary coil (L1) in order to achieve a specific mutual arrangement of the primary coil (L1) and the secondary coil (L2). Secondary subsystem ( 2 ) in a system ( 1 . 2 ) for inductively charging a battery (BAT) of a vehicle ( 2 ) by means of an inductive coupling of a primary coil (L1) of a charging station ( 1 ) with a secondary coil (L2) of the vehicle ( 2 ), characterized by secondary side adjustment means (Ax2, Ay2, Az2, MA, ML) for automatically placing the secondary coil (L2) to achieve a particular mutual arrangement of the primary coil (L1) and the secondary coil (L2). System for inductively charging a battery (BAT) of a vehicle ( 2 ) by means of an inductive coupling of a primary coil (L1) of a charging station ( 1 ) with a secondary coil (L2) of the vehicle ( 2 ), characterized by primary-side adjustment means and / or secondary-side adjustment means for automatically placing the primary coil (L1) and secondary coil (L2) to achieve a specific mutual arrangement of the primary coil (L1) and the secondary coil (L2). System according to one of claims 11 to 13, comprising detection means ( 14 L1) for detecting a quality of the inductive coupling and for providing a detection signal representative of the detected coupling quality to the setting means (Ax1, Ay1, Az1, Ax2, Ay2, Az2, MA, ML) to perform the automatic placement in response to the detection signal , System according to one of claims 11 to 14, comprising current supply control means ( 14 ) for allowing a variation of at least one parameter of the energization of the primary coil (L1) and / or load control means ( 18 . 20 ) for allowing variation of at least one power consumption parameter of the secondary coil (L2).

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