A DEVICE FOR WIRELESSLY RECEIVING ELECTRIC ENERGY

Description

TECHNICAL FIELD OF THE INVENTION

[0001] The present invention relates to a device for wirelessly receiving electric energy to be transferred from a source of alternating current by electromagnetic coupling through a conducting transmitter loop connected to this source, said device comprising at least one conducting receiver loop configured to receive electric energy from a said source in the form of current induced therein through electromagnetic coupling when placed close to a said conducting transmitter loop, at least one capacitor connected into said receiver loop for being charged with electric energy through said current induced in the receiver loop, an arrangement configured to allow a portion of the current induced in said receiver loop to only flow in one direction to the capacitor for charging the capacitor and not flow in opposite direction and discharge the capacitor, and a capacitance connected to the receiver loop to tune this to a determined frequency.

[0002] Such a device may be used in any type of equipment to be wirelessly fed with electric energy, i.e. be energized by so called tele-powering. Such an equipment in the form of a balise to be arranged between two rails of a railway track to transmit data through antennas mounted beneath railway vehicles passing the balise is only one example of this type of equipment.

[0003] The particular application of the invention in a balise will hereinafter be discussed for illuminating the invention and the problems to be solved thereby without for that sake restricting the invention thereto.

[0004] Balises are used by railways to send information from the track side to passing trains. There are many ways to do this, and one method for this is to be found in the standard ERTMS, European Rail Traffic Management System. The balise link is based on electromagnetic coupling, that is, the balise on the ground and the ATP (Automatic Train Protection) antenna on the train constitute an air transformer whenever the antenna is located above (or in the direct vicinity of) the balise. The link is bi-directional and the frequencies used are radio short wave. The downlink is used to transmit power to the balise, which is accordingly received by the device defined in the introduction. The uplink is used to transmit data to the train, and the transmitter of such an uplink is powered by the electric energy received by said device. AU 2013206087 B2 is a document disclosing tele-powering of a balise in general.

[0005] Since the contact distance between a standard-size balise on the ground and the ATP antenna on the train is about 1 m, it means that the contact duration is highly speed dependent. Modern trains can travel at 100 m/s, which means that it takes 10 ms to move 1 m. This means that the time allowed for the balise to be tele-powered by the train and for the balise to send its ATP telegram comes to about 10 ms. This is a technical challenge. The railway track companies would like to have smaller balises and at the same time allow higher train speeds on their tracks, which means that the contact time for said tele-powering will be shrinking to levels requiring improvements in balise efficiency for meeting these demands.

BACKGROUND ART

[0006] Fig. 1 illustrates schematically the structure of a known device of the type defined in the introduction as used in a balise. 100 illustrates a source of alternating current arranged on board a rail vehicle. This source generates an alternating current in a conducting transmitter loop 101 on board the vehicle. When this transmitter loop 101 passes over a conducting receiver loop 102 in a said balise the alternating current in the transmitter loop 101 will through electromagnetic coupling generate a current in the receiver loop. The transmitter loop 101 and the receiver loop 102 have not to have the same shape and size for obtaining this. The current induced in the receiver loop 102 is rectified by the use of a bridge of diodes 103-106, which forms an arrangement configured to allow a rectified portion of the current induced in the receiver loop to only flow in one direction to a capacitor 107 connected into the receiver loop for being charged with electric energy through the current induced in the receiver loop. The charge (DC voltage) across the capacitor 107 may then be used for powering other electrical devices, such as a microprocessor. Furthermore, a capacitance in the form of a capacitor 108 is connected to the receiver loop to tune this to the frequency of transmitters of rail vehicles passing the balise.

[0007] Once the tele-powering is started by electromagnetic coupling the time it takes to charge the capacitor 107 to a determined voltage level decides the point of time at which a transmitter in the balise may send its ATP telegram to the antennas of the rail vehicles passing. This does then also decide at which speed a train may pass the balise and still receive a said telegram with important information therefrom. Accordingly, it is a desire to be able to shorten the charging time of said capacitor for enabling higher train speeds and/or smaller balises with respect to balises provided with a known device shown in Fig. 1.

[0008] A device of this type is known through EP 0 242 906 A1.

SUMMARY OF THE INVENTION

[0009] The present invention is defined by the features of the independent claims.

[0010] The object of the present invention is to provide a device of the type defined in the introduction being improved with respect to the device already known by a response time reduced with respect to that of the known device.

[0011] This object is according to the invention obtained by providing such a device with the features listed in the characterizing part of appended patent claim 1.

[0012] Accordingly, said capacitor is connected into the receiver loop by having opposite poles thereof directly connected to the receiver loop at a first location therealong, and the arrangement comprises at least one rectifying member, such as a rectifying diode, connected into the receiver loop at a second location therealong spaced with respect to the first location and configured to allow a rectified portion of the current induced in the receiver loop to only flow in one direction therethrough. Furthermore, the capacitance for said tuning is connected into the receiver loop at said second location.

[0013] The voltage across said capacitor will be higher than in the known device in which it will be a voltage drop across each diode, since the diode bridge has been replaced by said rectifying member connected into the receiver loop. This means that the time it will take to charge the capacitor to a predetermined level will be shortened, so that in the case of the device used in a balise a transmitter in the balise powered by the capacitor will earlier be able to send a message to the train passing allowing this to pass the balise with a higher speed than a balise provided with a known device. Thus, the critical wake up time of the balise will be shortened by a device according to the invention.

[0014] According to an embodiment of the invention said first and second locations are at opposite positions along said receiver loop, which means that the rectifying member and the tuning capacitance are arranged in one side of the receiver loop and the capacitor to be charged on the opposite side, which keeps the receiver device balanced and less sensitive to stray capacitances than an unbalanced receiver device.

[0015] According to another embodiment of the invention said tuning capacitance is connected in parallel to said rectifying member, and the rectifying member is according to another embodiment preferably a rectifying diode. The tuning capacitance may then be formed by the inherent capacitance of the diode or be provided by a capacitor connected in parallel to the diode.

[0016] According to another embodiment of the invention the general shape and size of the receiver loop defined by receiver loop portions between said first and second locations are substantially identical to the shape and size of a said conducting transmitter loop from which the receiver loop is configured to receive electric energy, which may increase the efficiency of the tele-powering by electromagnetic coupling, and it is then advantageous that the general shape of the receiver loop is symmetrical with rectifying member and capacitor to be charged on opposite sides.

[0017] According to another embodiment of the invention the device comprises a plurality of said conducting receiver loops superimposed and a rectifying member connected into an individual receiver loop is configured to allow current induced in that receiver loop to only flow in the opposite direction therethrough with respect to what a rectifying member in a neighbouring receiver loop is configured to allow. This means that every second receiver loop will be active and charging the capacitor in question during a half period of the alternating current of a said source, and that the neighbouring receiver loops will be active in that sense during the other half period of the alternating current, so that the capacitors are charged all the time and a DC source formed by said capacitors will be more efficient than in the case of only one receiver loop, since losses with respect to the utility power will be lower than for a device having only one receiver loop. Furthermore, the currents in adjacent receiver loops will be out of phase, which means that harmonics in the currents induced will also be out of phase and they will counteract each other. This means that harmonics in the induced currents are greatly reduced, which is a very desirable property.

[0018] According to another embodiment of the invention all said at least one capacitor of the receiver loops are interconnected to together form an assembly storing electric energy, which accordingly results in an efficient DC source to be used by equipment in which the device according to the invention is integrated.

[0019] According to another embodiment of the invention said interconnected capacitors are connected in parallel to each other.

[0020] According to another embodiment of the invention said interconnected capacitors are connected in series to provide a voltage of said assembly formed by an addition of the voltages across all said capacitors. The way of interconnecting said capacitors chosen will be dependent upon the type of load to be connected thereto. A series connection may be selected when there is a need to generate high voltages, and a parallel connection when high currents are of more importance.

[0021] According to another embodiment of the invention the number of receiver loops is even, which results in an optimum of the reduction of harmonics created in the device.

[0022] The invention also relates to a balise according to the preamble of the appended claim directed thereto and which comprises a device according to the present invention for wirelessly receiving electric energy from a transmitter in a rail vehicle antenna. The advantages of providing a balise with a device according to the present invention appear clearly from the above discussion of the device according to the invention and embodiments thereof.

[0023] Further advantages and advantageous features of the invention will appear from the description following below.

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] With reference to the appended drawings, below follows a specific description of embodiments of the invention cited as examples.

[0025] In the drawings:

Fig. 1

is a simplified view very schematically illustrating the structure of a known device of the type to which the present invention belongs,

Fig. 2-4

are views corresponding to Fig. 1 of devices according to a first, second and third, respectively, embodiment of the invention, and

Fig. 5

is a graph showing the DC voltage across the capacitor charged versus time obtained by electromagnetic coupling for the devices shown in Fig. 1, 2 and 3.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

[0026] A device 1 for wirelessly receiving electric energy to be transferred from a source 2 of alternating current by electromagnetic coupling through a conducting transmitter loop 3 is shown in Fig. 2. This device has a conducting receiver loop 4 configured to receive electric energy from said source 2 in the form of current induced therein through electromagnetic coupling when placed close to said conducting transmitter loop 3. A capacitor 5 is connected into the receiver loop by having opposite poles 6, 7thereof directly connected to the receiver loop at a first location 8 therealong. An arrangement 9 configured to allow a rectified portion of current induced in the receiver loop to only flow in one direction the capacitor 5 for charging the capacitor and not flow in opposite direction, which would discharge the capacitor, is formed by a diode 10. This diode is connected into the receiver loop at a second location 11 therealong spaced with respect to the first location. A capacitance in the form of a capacitor 12 is connected into the receiver loop in parallel with the diode 10 at said second location for tuning the receiver loop to a determined frequency.

[0027] The diode bridge in the known device shown in Fig. 1 has here been replaced by a single diode 10. This means that the voltage across the charged capacitor will be higher, since for instance in case of voltage thereacross of 4 V the voltage across the capacitor of the device in Fig. 1 would only be approximately 3 V owing to a voltage drop in the order of 0.2-0.5 V across each diode. This higher voltage shortens the charging time needed for reaching a predetermined voltage level, such as 3 V, of the capacitor for enabling this to be used as a source for powering for instance a microprocessor. However, charging of a capacitor will only take place every second half period of the induced current, which lengthens the charging time. By moving the diode 10 and the tuning capacitor 12 to an opposite side of the receiver loop 4, the receiver device will be kept balanced and less sensitive to stray capacitances. Furthermore, the removal of the diode bridge means that for a determined size of the device the receiver loop 4 may be made larger resulting in a more efficient transfer of energy and data while interacting with the transmitter loop 3, or the device may be made smaller without for that sake making the receiver loop smaller. Thus, in the case of a balise provided with said device the balise may be made smaller and the capacity thereof still be maintained with respect to transfer efficiency and improved with respect to starting time of said data transfer.

[0028] A device according to a second embodiment of the invention is shown in Fig. 3. This device has two conducting receiver loops 20, 21 superimposed. A diode 22, 23 connected into an individual receiver loop is configured to allow current induced in that receiver loop to only flow in the opposite direction therethrough with respect to what a diode in the other receiver loop is configured to allow. This means that each receiver loop will be active during "its" half-period. The capacitors 24, 25 of the two receiver loops are interconnected and connected in parallel. Thus, charging goes on all the time, not just every second half-period, so that a more efficient DC source than the one in the embodiment shown in Fig. 2 is created. This receiving device is also balanced. As mentioned above the currents induced in the receiver loops are always out of phase, so that harmonics will also be out of phase and they will counteract each other and by that greatly reduced.

[0029] Fig. 4 illustrates a device according to a third embodiment of the invention differing from that shown in Fig. 3 by having the capacitors 24, 25 connected in series which means that the voltage obtainable across the DC-source obtained through the two capacitors will be doubled with respect to that in the embodiment shown in Fig. 3. Which type of interconnection of the capacitors, in parallel or in series, is selected can be based on the need to generate high voltages or high currents.

[0030] As example of a load which may be powered by the DC voltage of the capacitor/capacitors charged a transmitter 26 and a conducting transmitter loop 27 for transmission of data in the case of having the receiving device included in a balise are indicated in Figs 2-4.

[0031] The graph of Fig. 5 illustrates the DC voltage U across the DC source formed by the capacitor (capacitors in Fig. 3) charged versus time t for the three designs shown in Fig. 1, Fig. 2 and Fig. 3. It appears clearly that the charging-up process will be slower and the obtainable voltage will be lower for the known device shown in Fig. 1 (a), whereas the devices shown in Fig. 2 (b) and Fig. 3 (c) perform similarly with respect to charging-up time and voltage obtainable. If we assume that a DC voltage of 2.9 V is needed for starting a microprocessor powered by this voltage source the time needed for this will for the device shown in Fig. 1 be t₁ and for the devices shown in Fig. 2 and 3 t₂ being approximately half as long. This means for the case of having such a device in a balise a possibility to allow considerably higher train speeds and still ensuring a proper transfer of electric energy and messages between a train and the balise.

[0032] Although not shown in the figures, it is pointed out that each receiver loop may have more than one turn, i.e. be a multi turn loop, and then in a suitable turn include a connection to the components shown to the left in the figures and in a suitable turn include a connection to the components shown to the right in the figures. These two suitable turns may be the same or different depending upon balancing issues.

Claims

1. A device for wirelessly receiving electric energy to be transferred from a source (2) of alternating current by electromagnetic coupling through a conducting transmitter loop (3) connected to this source,
said device comprising

• at least one conducting receiver loop (4, 20, 21) configured to receive electric energy from a said source in the form of current induced therein through electromagnetic coupling when placed close to a said conducting transmitter loop,

• at least one capacitor (5, 24, 25) connected into said receiver loop (4, 20, 21) for being charged with electric energy through said current induced in the receiver loop,

• an arrangement (9) configured to allow a portion of the current induced in said receiver loop to only flow in one direction to the capacitor for charging the capacitor and not flow in opposite direction and discharge the capacitor, and

• a capacitance (12) connected to the receiver loop to tune this to a determined frequency,

characterized in that said at least one capacitor (5, 24, 25) is connected into the receiver loop by having opposite poles thereof directly connected to the receiver loop (4, 20, 21) at a first location (8) therealong, that said arrangement comprises at least one rectifying member (10, 22, 23) connected into the receiver loop at a second location (11) therealong spaced with respect to said first location and configured to allow a rectified portion of the current induced in the receiver loop to only flow in one direction therethrough, and that said capacitance (12) is connected into the receiver loop at said second location (11).

2. A device according to claim 1, characterized in that said first (8) and second (11) locations are at opposite positions along said receiver loop (4, 20, 21).

3. A device according to claim 1 or 2, characterized in that said tuning capacitance (12) is connected in parallel to said rectifying member (10, 22, 23).

4. A device according to any of the preceding claims, characterized in that said rectifying member is a rectifying diode (10, 22, 23).

5. A device according to claim 4, characterized in that said tuning capacitance is an inherent capacitance of said rectifying diode or is provided by a capacitor (12) connected in parallel to said diode (10, 22, 23).

6. A device according to any of the preceding claims, characterized in that said device further comprises the conducting transmitter loop (3), the conducting transmitter loop (3) having a shape and a size, whereby the general shape and size of the receiver loop (4, 20, 21) defined by receiver loop portions between said first (8) and second (11) locations are substantially identical to the shape and size of the conducting transmitter loop (3) from which the receiver loop is configured to receive electric energy.

7. A device according to claim 6, characterized in that said general shape of the receiver loop (4, 20, 21) is symmetrical with rectifying member (10, 22, 23) and capacitor (5, 24, 25) to be charged on opposite sides.

8. A device according to any of the preceding claims, characterized in that it comprises a plurality of said conducting receiver loops (20, 21) superimposed, and that a rectifying member (22, 23) connected into an individual receiver loop is configured to allow current induced in that receiver loop to only flow in the opposite direction therethrough with respect to what a rectifying member in a neighbouring receiver loop is configured to allow.

9. A device according to claim 8, characterized in that all said at least one capacitor (24, 25) of the receiver loops are interconnected to together form an assembly storing electric energy.

10. A device according to claim 9, characterized in that said interconnected capacitors (24, 25) are connected in parallel to each other.

11. A device according to claim 9, characterized in that said interconnected capacitors (24, 25) are connected in series to provide a voltage of said assembly formed by an addition of the voltages across all said capacitors.

12. A device according to any of claims 8-11, characterized in that the number of receiver loops (20, 21) is even.

13. A balise to be arranged between the two rails of a railway track to transmit data to antennas mounted beneath railway vehicles passing the balise, said balise comprising

• a conducting receiver loop (4, 20, 21) configured to receive electric energy by electromagnetic coupling from a transmitter in said rail vehicle antennas when passing the balise,

• a transmitter (26) configured to be powered by the electric energy received by the receiver loop, and

• a conducting transmitter loop (27) configured to be fed by said transmitter to transmit data to said railway vehicle antennas passing the balise,

characterized in that it comprises a device (1) according to any of the preceding claims for wirelessly receiving electric energy from a said transmitter.

Ansprüche

1. Vorrichtung zum drahtlosen Empfangen von elektrischer Energie, die von einer Wechselstromquelle (2) durch elektromagnetische Kopplung durch eine mit dieser Quelle verbundene leitende Senderschleife (3) zu übertragen ist,
wobei die Vorrichtung umfasst

• mindestens eine leitende Empfängerschleife (4, 20, 21), die dazu konfiguriert ist, elektrische Energie von einer Quelle in Form von Strom zu empfangen, der durch elektromagnetische Kopplung im Fall einer Platzierung in der Nähe der leitenden Senderschleife induziert wird,

• mindestens ein Kondensator (5, 24, 25), der in die Empfängerschleife (4, 20, 21) geschaltet ist, um durch den in der Empfängerschleife induzierten Strom mit elektrischer Energie geladen zu werden,

• eine Anordnung (9), die dazu konfiguriert ist, einen Teil des in der Empfängerschleife induzierten Stroms nur in eine Richtung zum Kondensator zum Laden des Kondensators zum Kondensator fließen zu lassen und nicht in entgegengesetzter Richtung fließen zu lassen, um den Kondensator zu entladen, und

• eine Kapazität (12), die mit der Empfängerschleife verbunden ist, um diese auf eine vorgegebene Frequenz abzustimmen,

dadurch gekennzeichnet, dass der mindestens eine Kondensator (5, 24, 25) in die Empfängerschleife geschaltet ist, indem entgegengesetzte Pole davon direkt mit der Empfängerschleife (4, 20, 21) an einer ersten Stelle (8) entlang dieser verbunden sind, dass die Anordnung mindestens ein Gleichrichtungselement (10, 22, 23) umfasst, das in die Empfängerschleife an einer zweiten Stelle (11) entlang dieser geschaltet ist, die zu der ersten Stelle beabstandet ist und dazu konfiguriert ist, einen gleichgerichteten Teil des in der Empfängerschleife induzierten Stroms nur in einer Richtung durch diese fließen zu lassen, und dass die Kapazität (12) an der zweiten Stelle (11) in die Empfängerschleife geschaltet ist.

2. Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, dass sich die erste (8) und die zweite Stelle (11) an entgegengesetzten Positionen entlang der Empfängerschleife (4, 20, 21) befinden.

3. Vorrichtung nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass die abstimmende Kapazität (12) parallel zu dem Gleichrichtungselement (10, 22, 23) geschaltet ist.

4. Vorrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass das Gleichrichtungselement eine Gleichrichtungsdiode (10, 22, 23) ist.

5. Vorrichtung nach Anspruch 4, dadurch gekennzeichnet, dass die abstimmende Kapazität eine inhärente Kapazität der Gleichrichterdiode ist oder durch einen Kondensator (12) bereitgestellt ist, der parallel zu der Diode (10, 22, 23) geschaltet ist.

6. Vorrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass die die Vorrichtung die leitende Senderschleife (3) umfasst, die eine Form und Größe aufweist, wobei die allgemeine Form und Größe der Empfängerschleife (4, 20, 21), die durch Empfängerschleifenabschnitte zwischen den ersten (8) und zweiten (11) Stellen definiert ist, im Wesentlichen identisch ist mit der Form und Größe der leitenden Senderschleife (3), von der die Empfängerschleife konfiguriert ist, elektrische Energie zu empfangen.

7. Vorrichtung nach Anspruch 6, dadurch gekennzeichnet, dass die allgemeine Form der Empfängerschleife (4, 20, 21) symmetrisch ist mit dem Gleichrichtungselement (10, 22, 23) und dem zu ladenden Kondensator (5, 24, 25) auf gegenüberliegenden Seiten.

8. Vorrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass sie eine Mehrzahl dieser leitendenden Empfängerschleifen (20, 21) überlagert umfasst und dass ein in eine einzelne Empfängerschleife geschaltetes Gleichrichtungselement (22, 23) dazu konfiguriert ist, in dieser Empfängerschleife induzierten Strom, nur in einer Richtung durch diese fließen zu lassen, die entgegengesetzt ist zu derjenigen, welche die Konfiguration eines Gleichrichtungselements in einer benachbarten Empfängerschleife zulässt.

9. Vorrichtung nach Anspruch 8, dadurch gekennzeichnet, dass alle der mindestens einen Kondensatoren (24, 25) der Empfängerschleifen miteinander verbunden sind, um zusammen eine Baugruppe zu bilden, die elektrische Energie speichert.

10. Vorrichtung nach Anspruch 9, dadurch gekennzeichnet, dass die miteinander verbundenen Kondensatoren (24, 25) parallel zueinander geschaltet sind.

11. Vorrichtung nach Anspruch 9, dadurch gekennzeichnet, dass die miteinander verbundenen Kondensatoren (24, 25) in Reihe geschaltet sind, um eine Spannung der Anordnung bereitzustellen, die durch Addition der Spannungen über alle Kondensatoren gebildet wird.

12. Vorrichtung nach einem der Ansprüche 8 bis 11, dadurch gekennzeichnet, dass die Anzahl der Empfängerschleifen (20, 21) gerade ist.

13. Balise, die zwischen den beiden Schienen einer Eisenbahnstrecke anzuordnen ist, um Daten an Antennen zu übertragen, die unter Eisenbahnfahrzeugen montiert sind, die die Balise passieren, wobei die Balise umfasst

• eine leitende Empfängerschleife (4, 20, 21) umfasst, die dazu konfiguriert ist, von einem Sender in den Schienenfahrzeugantennen beim Passieren der Balise elektrische Energie durch elektromagnetische Kopplung zu empfangen,

• einen Sender (26), der dazu konfiguriert ist, von der durch die Empfängerschleife empfangenen elektrischen Energie gespeist zu werden, und

• eine leitende Senderschleife (27), die dazu konfiguriert ist, von dem Sender gespeist zu werden, um Daten an die Eisenbahnfahrzeugantennen zu übermitteln, welche die Balise passieren,

dadurch gekennzeichnet, dass sie eine Vorrichtung (1) gemäß einem der vorhergehenden Ansprüche umfasst, um drahtlos elektrische Energie von einem Sender zu empfangen.

Revendications

1. Dispositif de réception sans fil d'énergie électrique à transférer depuis une source (2) de courant alternatif par couplage électromagnétique par le biais d'une boucle d'émetteur conductrice (3) connectée à cette source,
ledit dispositif comprenant

• au moins une boucle de récepteur conductrice (4, 20, 21) configurée pour recevoir de l'énergie électrique depuis une dite source sous forme de courant induit dans celle-ci par le biais d'un couplage électromagnétique lorsqu'elle est placée près d'une dite boucle d'émetteur conductrice,

• au moins un condensateur (5, 24, 25) connecté dans ladite boucle de récepteur (4, 20, 21) pour être chargé en énergie électrique par le biais dudit courant induit dans la boucle de récepteur,

• un agencement (9) configuré pour permettre à une portion du courant induit dans ladite boucle de récepteur de circuler uniquement dans une direction vers le condensateur pour charger le condensateur et de ne pas circuler en direction opposée et décharger le condensateur ; et

• une capacité (12) connectée à la boucle de récepteur pour accorder celle-ci à une fréquence déterminée,

caractérisé en ce que ledit au moins un condensateur (5, 24, 25) est connecté dans la boucle de récepteur en ayant des pôles opposés de celui-ci connectés directement à la boucle de récepteur (4, 20, 21) à un premier emplacement (8) le long de celle-ci, en ce que ledit agencement comprend au moins un organe de redressement (10, 22, 23) connecté dans la boucle de récepteur à un second emplacement (11) le long de celle-ci espacé par rapport audit premier emplacement et configuré pour permettre à une portion redressée du courant induit dans la boucle de récepteur de circuler uniquement dans une direction au travers, et en ce que ladite capacité (12) est connectée dans la boucle de récepteur audit second emplacement (11).

2. Dispositif selon la revendication 1, caractérisé en ce que lesdits premier (8) et second (11) emplacements sont à des positions opposées le long de ladite boucle de récepteur (4, 20, 21).

3. Dispositif selon la revendication 1 ou 2, caractérisé en ce que ladite capacité d'accord (12) est connectée en parallèle audit organe de redressement (10, 22, 23) .

4. Dispositif selon l'une quelconque des revendications précédentes, caractérisé en ce que ledit organe de redressement est une diode de redressement (10, 22, 23).

5. Dispositif selon la revendication 4, caractérisé en ce que ladite capacité d'accord est une capacité inhérente de ladite diode de redressement ou est fournie par un condensateur (12) connecté en parallèle à ladite diode (10, 22, 23).

6. Dispositif selon l'une quelconque des revendications précédentes, caractérisé en ce que ledit dispositif comprend en outre la boucle d'émetteur conductrice (3), la boucle d'émetteur conductrice (3) ayant une forme et une taille, moyennant quoi la forme et la taille générales de la boucle de récepteur (4, 20, 21) définies par des portions de boucle de récepteur entre lesdits premier (8) et second (11) emplacements sont sensiblement identiques à la forme et à la taille de la boucle d'émetteur conductrice (3) depuis laquelle la boucle de récepteur est configurée pour recevoir de l'énergie électrique.

7. Dispositif selon la revendication 6, caractérisé en ce que ladite forme générale de la boucle de récepteur (4, 20, 21) est symétrique à l'organe de redressement (10, 22, 23) et au condensateur (5, 24, 25) à charger sur des côtés opposés.

8. Dispositif selon l'une quelconque des revendications précédentes, caractérisé en ce qu'il comprend une pluralité desdites boucles de récepteur conductrices (20, 21) superposées, et en ce qu'un organe de redressement (22, 23) connecté dans une boucle de récepteur individuelle est configuré pour permettre à un courant induit dans cette boucle de récepteur de circuler uniquement dans la direction opposée au travers par rapport à ce qu'un organe de redressement dans une boucle de récepteur voisine est configuré pour permettre.

9. Dispositif selon la revendication 8, caractérisé en ce que la totalité desdits au moins un condensateur (24, 25) des boucles de récepteur sont interconnectés pour former ensemble un ensemble stockant de l'énergie électrique.

10. Dispositif selon la revendication 9, caractérisé en ce que lesdits condensateurs interconnectés (24, 25) sont connectés en parallèle les uns aux autres.

11. Dispositif selon la revendication 9, caractérisé en ce que lesdits condensateurs interconnectés (24, 25) sont connectés en série pour fournir une tension dudit ensemble formée par une addition des tensions aux bornes de tous lesdits condensateurs.

12. Dispositif selon l'une quelconque des revendications 8 à 11, caractérisé en ce que le nombre de boucles de récepteur (20, 21) est pair.

13. Balise à agencer entre les deux rails d'une voie ferrée pour transmettre des données à des antennes montées sous des véhicules ferroviaires passant la balise, ladite balise comprenant

• une boucle de récepteur conductrice (4, 20, 21) configurée pour recevoir de l'énergie électrique par couplage électromagnétique depuis un émetteur dans lesdites antennes de véhicules ferroviaires au passage de la balise,

• un émetteur (26) configuré pour être mis sous tension par l'énergie électrique reçue par la boucle de récepteur, et

• une boucle d'émetteur conductrice (27) configurée pour être alimentée par ledit émetteur pour transmettre des données auxdites antennes de véhicules ferroviaires passant la balise,

caractérisée en ce qu'elle comprend un dispositif (1) selon l'une quelconque des revendications précédentes de réception sans fil d'énergie électrique depuis un dit émetteur.

Drawing