TW201724701A - Charging point, charging device and charging system for the inductive charging of an energy store, and method for the inductive charging of an energy store - Google Patents

Abstract

The present invention relates to the checking of a magnetic coupling and safety-related components prior to an inductive energy transfer for charging an electrical energy store. To do this, the secondary-side oscillating circuit of an inductive energy transfer system is first short-circuited and current and voltage are then evaluated on both the primary side and the secondary side. The coupling factor and secondary-side safety functions can thus be checked simultaneously without measured values having to be exchanged between the primary side and the secondary side for this purpose.

Description

Charging station for inductive charging of energy storage, charging device, charging system, and method for inductive charging of energy storage

The present invention relates to a charging station and charging device for inductive charging of an energy storage device, a charging system for inductive charging of an energy storage device in a carrier, and an induction for an energy storage device Method of charging.

German Patent Application No. 10 2012 219 985 A1 discloses a device for inductive energy transfer to an electrically drivable carrier. The device for inductive energy transfer in this document comprises a first coil having a shield made of a ferromagnetic material for reducing a stray magnetic field.

For inductive charging of electrical vehicles, a primary coil is typically a charging panel that is inserted into the floor or embedded in the floor. A secondary coil system is usually permanently mounted under the floor of a carrier. The two coils thus form a transformer with a large air gap. For energy transfer, the primary coil produces a high frequency alternating magnetic field that penetrates the secondary coil and senses a corresponding current there. In order to have to transfer as little reactive power as possible via the air gap, a resonant operating system is provided in an oscillating circuit. This is the An inductor of a primary coil is composed of a resonant capacitor. The coil inductor, together with a further capacitor, also forms an oscillating circuit on the secondary side. Both oscillator circuits are designed and operated at the same resonant frequency.

For a safe and efficient energy transfer from the primary coil to the secondary coil, the two coil systems must be as precisely aligned as possible to each other. Before the start of the charging process, it must be ensured for this purpose that a suitably sufficient magnetic coupling is present between the primary coil and the secondary coil. In addition, an inspection system must be implemented at the beginning of the charging process to determine if the necessary safety-related components are operational.

Therefore, a need exists for a charging station and charging device for inductive charging of an energy storage device, which enables inspection in an inductive charging system to be performed in a simple manner. In particular, a need for a low cost, efficient, and safe inspection of a system for inductive energy transfer to charge an energy storage is present.

According to a first aspect, the apparatus of the present invention proposes a charging station for inductive charging of an electrical energy storage device having the features of the independent item 1 of the patent application.

Therefore, the present invention proposes a charging station for inductive charging of an electric energy storage device having a primary coil, a feed-in device, a measuring device, and a release device. The feedthrough is designed to apply a predetermined test voltage to the primary coil or to feed a predetermined test current to the primary coil. The measuring device is designed to measure one of the primary coils to generate a feed current or one of the primary coils to generate a feed voltage. The releasing device is designed to solve if the measured feeding current drops below a predetermined first primary side threshold or the measured feeding voltage exceeds a predetermined first primary side threshold In addition to a charging process for inductive charging.

According to still another aspect, the present invention provides a charging device for inductive charging of an energy storage device having the features of the independent item 4 of the patent application.

Therefore, the present invention proposes a charging device for inductive charging of an energy storage device having an oscillating circuit, a switching device, a current measuring device and a control device. The oscillating circuit includes a secondary coil. In particular, the oscillating circuit may comprise a series circuit consisting of the secondary coil and a resonant capacitor. The switching device has a first connection and a second connection. The switching device is in turn designed to electrically interconnect the two connection points of the oscillating circuit. In particular, the switching device can short-circuit its series circuit consisting of a secondary coil and a resonant capacitor. The current measuring device is designed to measure an electrical test current in the secondary coil or in an oscillating circuit having the secondary coil. The control device is designed to control the switching device. In particular, the control device is designed to control the switching device only for the electrical connection or disconnection of the two connection points of the oscillating circuit. The control device is further designed to release the charging process for inductive charging if the measured current measured in the secondary coil exceeds a predetermined secondary side threshold. The measurement of the electrical test current by the current measuring device and the release of the control device are carried out, in particular if the switching device has electrically interconnected the two connection points of the oscillating circuit.

According to still another aspect, the present invention provides a method for inductive charging of an energy storage device having the features of the independent item 9 of the patent application.

Therefore, the present invention provides a method for inductive charging of an energy storage device having the steps of: short-circuiting an oscillating circuit having a secondary coil by a switching device; and, setting a predetermined test voltage Or a predetermined test current is fed to one Primary coil. The method further includes the step of measuring one of the primary coils to generate a feed current or one of the primary coils to generate a feed voltage. The method further comprises the step of measuring a test current generated in one of the secondary coils or in an oscillating circuit having the secondary coil. The method further includes the step of: if the measured test current in the secondary coil exceeds a predetermined secondary side threshold and the measured feed current to the primary coil drops below one The inductive charging is released by a predetermined threshold or a measured feed voltage above the primary coil that exceeds a predetermined first primary side threshold.

Advantages of the invention

The present invention is based on the concept of checking the coupling of a system for inductive energy transfer by applying a defined, time-controlled sequence at system startup. In particular, this sequence can be performed prior to energy transfer. The magnetic coupling of such a system can be checked by the sequence according to the invention. Furthermore, for example, a short circuit of the secondary side oscillating circuit or the secondary coil, the safety stop function can be simultaneously checked. A reproducible load in the form of an electrical short is applied to the secondary side for inspection at the beginning of the inductive energy transfer. The function of this secondary side short circuit as a safety feature and the magnetic coupling factor for inductive energy transfer can therefore be checked simultaneously, without the need to exchange measurements between the primary side and the secondary side for this test. It is thus possible to perform an independent inspection system for potential failures based on known system characteristics on both sides.

Since no safety-related data has to be exchanged between the primary side and the secondary side for this inspection, an unprotected and simple transmission path is sufficient for the synchronization of the primary side and the secondary side. The modest requirement for this transmission channel thus enables a low cost implementation, and the overall system price is also reduced due to it.

In addition, various systems can be implemented simply and quickly with regard to protection requirements. An interactive check such as, for example, a secondary side shutdown of a short circuit through the oscillating circuit on the secondary side.

Since the system components necessary for the short circuit of the current or voltage fed in the primary side and the secondary side (such as a measuring device for measuring primary current and secondary current) are similarly present, the inspection system according to the present invention It can be implemented at low cost by making minor modifications to the charging station and the charging device.

According to one embodiment, the release device of the charging station is designed to classify a fault based on the measured feed current or the measured feed voltage. In particular, the measured feed current or measured feed voltage can be compared to the threshold of the other primary side for this purpose. In this way, it is also possible to distinguish between failures due to improper magnetic coupling and failures due to poor short-circuiting on the secondary side. In view of the fact that a safety-related deficiency occurs when a failure due to a bad short circuit on the secondary side occurs and the inductive energy transfer system cannot be released, if necessary, an insufficient magnetic coupling system can be transmitted once. The alignment between the coil and the secondary coil is corrected and subsequently corrected.

According to another embodiment, a feed device for a charging station for inductive charging is designed to increase the current in the primary coil or across the voltage of the primary coil until the voltage across the primary coil is passed or passed A predefined limit of the current of the primary coil is reached. If a predefined limit value for voltage or current is not reached, even with a maximum predefined current or a maximum predefined voltage, a fault system can be inferred in this case. If necessary, the operational capability can be checked with a relatively low current or voltage by passing a ramp to current or voltage during the inspection.

According to yet another embodiment, a charging device for inductive charging of an energy storage device includes a voltage measuring device designed to measure a first connection at the switching device An electrical test voltage between the second connections. If the voltage measuring device is capable of detecting a significant voltage when the switching device is closed, the voltage is generated by the voltage induced in the secondary coil, and a fault of the safety-related switching device can be inferred therefrom. The control device of the charging device releases the charging process for inductive charging only if the measured test voltage drops below a predefined limit value for the test voltage when the switching device is closed.

According to still another embodiment, the charging device includes a communication device designed to transmit a signaling to the charging station if the first connection and the second connection of the switching device are electrically interconnected. In particular, it can be signaled by the communication device that the necessary requirements for the inspection are met on the secondary side, and that one inspection and, if necessary, a subsequent energy transfer system for inductive charging will take place.

According to another embodiment, the communication device of the charging device is designed to transmit information regarding the release of the charging process to the charging station if the control device has released the charging process for inductive charging. In this way, the results of inspections on the secondary side of the system components can also be transmitted to the primary side. If the release system is present on the primary side and the secondary side, the energy transfer system for charging of an energy storage can thus start on the primary side.

According to yet another embodiment, the charging device includes a communication device designed to receive a transmission from a charging station for initialization of a charging process.

According to still another aspect, the present invention provides a charging system for inductive charging of an energy storage device in a carrier, having a charging station according to the present invention, and a charging device having a charging device according to the present invention vehicle.

According to still another embodiment of the method for inductive charging, the step of de-inductive charging is only if the voltage across the shorted oscillating circuit having the secondary coil drops to The inductive charging is released below a predefined limit voltage.

Further embodiments and advantages of the invention are apparent from the following description with reference to the accompanying drawings.

1‧‧‧Charging station

2‧‧‧Charging device

3‧‧‧ Vehicles

10‧‧‧Removal device

11‧‧‧Feeding device

12‧‧‧One coil

13‧‧‧Primary current measuring device

14‧‧‧Primary side voltage measuring device

15‧‧‧One-side communication device

20‧‧‧Control device

21‧‧‧Switching device

22‧‧‧second coil

23‧‧‧Second-side current measuring device

24‧‧‧Secondary voltage measuring device

25‧‧‧secondary communication device

26‧‧‧Rectifier

27‧‧‧Battery protection circuit

28‧‧‧ Energy storage

In the drawings: FIG. 1 is a schematic diagram showing a charging system for inductive charging of an energy storage device among carriers according to an embodiment; FIG. 2 is a diagram showing a charging station according to an embodiment. The charging system of the charging device is a schematic diagram of a circuit diagram based on its type; and FIG. 3 is a schematic diagram showing a flow chart for inductive charging of the energy storage device based on its type.

1 is a schematic diagram showing a charging system for inductive charging of an energy storage device. The charging system includes a charging station 1. Charging stations 1 for inductive charging are known per se. The principle of action for inductive energy transfer, and in particular the control of a primary coil with a high switching frequency by a corresponding converter, will therefore not be discussed in detail herein. For energy transfer, the charging station 1 produces a high frequency alternating magnetic field that is coupled to a secondary coil of a charging device 2. For example, the charging device 2 can have one secondary coil that is mounted to the floor, or any other member that is on the outside of the carrier 3. A voltage system is thus induced in the secondary coil of the charging device 2 by the alternating current field of the charging station 1. This voltage can be rectified and connected to charge an electrical energy storage such as, for example, a traction battery for an electrical vehicle.

2 is a schematic diagram showing a circuit diagram for a charging station 1 and a charging device 2 according to an embodiment. The charging station 1 includes a primary coil 12. This primary coil 12 can be combined with a primary side capacitor C _P to form a series oscillating circuit. This series oscillating circuit is fed by a feed device 11. During normal charging operation, the feedthrough 11 supplies a high frequency voltage which is thereby excited. This may involve, for example, an excitation of approximately 85 Hz. However, higher or lower frequencies for exciting the oscillating circuit are also possible. However, the voltage supplied by the feedthrough 11 typically has a frequency that is tuned to the resonant frequency of the series oscillating circuit of the charging station 1. The illustrated resistor R _P represents the parasitic ohmic losses on the primary side.

At the beginning of an energy transfer from the charging station 1 to the charging device 2, an inspection of the magnetic coupling and the necessary safety shutdown function with respect to the secondary side is carried out. To do this, the secondary coil 22 of the charging device must first be positioned as accurately as possible with respect to the primary coil 12 of the charging station. For the charging of the traction battery of the electrical carrier 3, the electrical carrier 3 is arranged as precisely as possible for this purpose on a primary coil 12 which is arranged on the floor or a floor panel. If necessary, the data can then be exchanged between the carrier 3 and the charging station 1. Such information may include information such as information regarding expected energy requirements, parameters for the charging process, authorization information, or billing for the amount of energy consumed. Such information may be, for example, transmitted from a communication device 25 of the charging device to a corresponding communication device 15 of the charging station. In particular, any wireless transmission method such as, for example, WLAN, Bluetooth, mobile radio (GSM or the like), and infrared transmission or the like is possible.

The charging device 2 comprises, in particular, an oscillating circuit which is formed by a series connection of a secondary coil 22 and a secondary side capacitor C _S . If a magnetic field is coupled from the primary coil 12 to the secondary coil 22, an alternating voltage is induced thereby, which can be rectified by a rectifier 26 at the output of the secondary side oscillating circuit. The output of rectifier 26 is coupled via a battery protection circuit 27 to an electrical energy storage 28 such as, for example, a traction battery or the like. If necessary, the charging device 2 can also include further components to control the charging current or charging voltage used to charge the energy storage 28.

In order to avoid a dangerous voltage rise or current at the output of the secondary side oscillating circuit in the event of a fault or a dangerous situation, the charging device 2 comprises a switching device 21. If necessary, the switching device 21 enables a safe shutdown of the secondary side oscillating circuit. For this purpose, the switching device 21 can electrically interconnect the two connection points A1 and A2 of the secondary side oscillating circuit and thus short-circuit. The switching device 21 can for example be a semiconductor switching element such as, for example, an IGBT or a MOSFET. However, other switching elements such as, for example, electrically controlled mechanical switching elements are equally possible.

If the secondary coil 22 is disposed above the primary coil 12 and the inductive energy transfer system for charging the energy storage 28 is about to begin, an initialization phase is first performed, wherein the secondary side is oscillated. The operational capability of the switching device 21 of the circuit short circuit and the magnetic coupling between the primary coil 12 and the secondary coil 22 are checked. For this purpose, the switching device 21 is first closed, ie an electrical connection is established between the first connection point A1 and the second connection point A2. In order to do this, the switching device 21 can for example be controlled by the control device 20. After the switching device 21 has thus been controlled to establish an electrical connection between the first connection point A1 and the second connection point A2, the control device 20 transmits a message to the charging station 1. For example, a communication path already existing between the communication device 25 on the secondary side of the charging device and the communication device 15 on the primary side of the charging station 1 can be used for this purpose. Since this is a simple message for the beginning of the initialization phase, there is no special data connection, especially Data connections without special protection are necessary.

As described above, the charging station 1 receives the transmission for the start of an initialization phase via the communication device 15 on the primary side. A predetermined test voltage is then applied to the primary coil 12 by the feedthrough 11 or the primary side oscillating circuit consisting of the primary coil 12 and the primary side capacitor C _P . The test voltage is preferably an AC voltage that also uses the same frequency during the actual energy transfer. In particular, the test voltage is an AC voltage in the resonance frequency range of the oscillation circuit of the primary side. However, the amplitude of this test voltage is typically less than the amplitude supplied by the feedthrough during the charging process. For example, a test voltage having an amplitude or effective value of approximately 10 volts may be supplied by the feed device during the initialization phase.

Although the predetermined test voltage is supplied from the feeding means 11, the current in the circuit composed of the feeding means and the oscillating circuit having the primary side of the primary coil 12 is measured by a primary side current measuring means 13. . The current value measured by the primary side current measuring device 13 can be evaluated by the releasing device 10. If the current measured by the current measuring device 13 on the primary side is relatively low, that is, if the measured current of the primary side, in particular the effective value of the measured current, falls below a predefined first threshold, It is inferred that the magnetic coupling between the primary coil 12 and the secondary coil 22 and the secondary side short circuit generated by the switching device 21 are sufficiently good. In this case, the release device 10 can release the charging process and in particular the inductive energy transfer from the charging station 1 to the charging device 2.

On the other hand, if the current measured by the current measuring device 13 on the primary side is very high, a magnetic coupling system that is not sufficiently high exists between the primary coil 12 and the secondary coil 22, and the releasing device 10 is not released. Inductive energy transfer of the charging process. If the current measured by the primary side current measuring device 13 is at the threshold of the first primary side and the higher second primary side Between the thresholds, there is no sufficient magnetic coupling or the switching device 21 in the charging device 2 has failed. Also in this case, the release device 10 can prevent the release of inductive energy transfer from the charging station to the charging device 2. If the measured feed current is above the second threshold, an insufficient magnetic coupling exists.

If the releasing device 10 of the charging station 1 can classify the insufficient magnetic coupling between the primary coil 12 and the secondary coil 22 based on the evaluation of the current measured by the primary side current measuring device 13, a corresponding hair The system can be displayed to the user. If necessary, the user can then re-adjust the carrier 3 with the secondary coil 22 so that the positioning of the secondary coil 22 relative to the primary coil 12 is optimized.

As an alternative to the above-mentioned feeding of a predefined test voltage by the feed means 11, it is also possible for a predefined test current to be fed by the feed means 11 to the primary coil 12 An oscillating circuit composed of a capacitor C _P on the primary side. In this case, the generated feed voltage can be measured by a primary side voltage measuring device 14. The measured feed voltage is similarly supplied to the release device 10 for evaluation. For example, the release device 10 can control the feedthrough device 11 such that a predefined test current system, such as a current having an effective value of about 1 amp, is fed. The releasing device 10 can evaluate the feeding voltage determined by the primary side voltage measuring device 14, and thus can infer the magnetic coupling with the operating capability of the switching device in the charging device 2. If the predefined test current system has been reached by a feed voltage that is below a predefined threshold, then an insufficient magnetic coupling system is present. On the other hand, if the feed voltage having the predetermined test current exceeds the threshold of the first primary side, a sufficient magnetic coupling system exists and the switching device 21 in the charging device 2 can be determined to operate. . If the feed voltage having a predetermined test current is between the threshold value of the first primary side and the threshold value of the second primary side, there is no sufficient magnetic coupling system or the charging device 2 The switching device 21 has a fault.

After a call for the beginning of an initialization phase, irrelevant and without further communication with the charging device 2, the aforementioned charging station 1 can thus be implemented with respect to a sufficient magnetic coupling and with respect to safety. One of the operational capabilities of the switching device 21 is checked and then the release of the inductive energy transfer is achieved.

Similarly, after the start of the initialization phase, irrespective of and without further communication with the charging station 1, the charging device 2 can also check the operational capability of the switching device 21 and between the primary coil 12 and the secondary coil 22. Full magnetic coupling. For this purpose, a secondary side electrical test current is measured by a secondary side current measuring device 23 in the current path of the secondary side oscillating circuit. The test current of this secondary side is evaluated by the control device 20. If the test current of the secondary side exceeds a predetermined threshold of the secondary side, then a sufficient magnetic coupling system exists in this case. One of the voltage drops across the two connections of the switching device 21 can be simultaneously measured by a secondary side voltage measuring device 24. If the voltage drop across the switching device 21 exceeds a predefined limit value, then a sufficiently good short circuit can be achieved by the switching device 21. In this case, if a danger occurs, it may be a safe shutdown that is not caused by the switching device 21. If the switching device 21 is closed and the voltage drop of more than one predefined limit is exceeded, a fault is therefore confirmed during the initialization phase.

If the failure of the switching device 21 or the insufficient good magnetic coupling between the primary coil 12 and the secondary coil 22 is confirmed, the charging process cannot be released by the control device 20. However, if a sufficiently high magnetic coupling (ie, more than one of the pre-defined limits of the primary side of the oscillating circuit) and simultaneously across the switching device 21 is less than a predefined limit value A voltage drop is detected during the initialization phase, and the charging process of the electrical energy storage 28 is released by the control device 20.

In order to be able to guarantee safety-related parameters during the entire charging process and associated inductive energy transfer, the secondary side of the oscillating circuit is short-circuited and evaluated at a predefined test voltage or a predefined test current applied once The aforementioned sequence of currents or voltages generated during the side period can be periodically repeated. For example, the sequence can be repeated periodically at predefined time intervals, for example: every 15, 30 or 60 minutes. For this purpose, a brief interruption of the inductive energy transfer by the short-circuit of the secondary side of the switching device 21 and the application of the test current or the test voltage on the primary side are necessary. After the magnetic coupling and safe shutdown have been successfully checked, the inductive energy transfer system for charging the energy storage 28 can then continue. In order to perform an inspection of this type during the charging process, an interruption of the inductive energy transfer must first be signaled, after which the switching device 21 can be closed to the secondary side and the inspection system can be implemented as described above. . Synchronization of this sequence can be carried out, for example, via a communication connection between the secondary side and the primary side communication means 25 and 15 or by shorting the switching means 21.

As an alternative to the application of a predefined test current or a predetermined test voltage to the feed device 11 during the initialization phase, it is also possible to continuously increase the test voltage or test current and evaluate the generated voltage or current. When the predefined limit value is reached, the generated feed current is determined with the generated feed voltage, and the operational capability or the magnetic coupling of the switching device 21 can be inferred in the same manner as previously described. Continuous improvement in test current or test voltage is based on safety and can be limited to a predefined limit.

3 is a schematic diagram showing a method for inductive charging of an energy storage device based on an embodiment of the present invention. In step S1, there is a secondary line An oscillating circuit of the ring 22 is first shorted by a switching device 21. At step S2, a predetermined test voltage or a predetermined test current is then fed to the primary coil. Next, in step S3, a generated feed current is measured in the primary coil or a generated feed voltage is measured in the primary coil. In parallel with this, in step S4, a generated test current is measured in the secondary coil. Next, in step S5, if the measured test current exceeds a predetermined secondary side threshold and the measured feed current is simultaneously decreased below a predetermined primary side threshold or measured feed voltage. The threshold value exceeds a predetermined primary side, and the inductive charging system is released. The inductive charging system in step S5 may also be reduced to a voltage lower than a predefined one only if it is across a short-circuited oscillating circuit having a secondary coil 22 (ie, across the switching device 21 of the charging device 2). The limit voltage is released.

In order to take into account any time delay during the sequence of the initialization phase, the evaluation of the current and voltage in the charging station 1 and the charging device 2 is only after the initialization of the initialization has been initiated by the charging device 2 to the charging station 1. Implemented for a predefined period of time. For example, the signaling system by charging device 2 can be followed by a 2 second wait until the desired system state is set and the inspection is performed.

The initialization phase can be further initiated by a communication from the communication device 15 on the primary side of the charging station to the communication device 25 on the secondary side of the charging device. If the secondary communication device 25 receives a corresponding one of the initializations, shorting the secondary coil 22 and evaluating the sequence of current and voltage can be performed.

In summary, the present invention relates to the inspection of a magnetic coupling and safety related component prior to inductive energy transfer for charging an electrical energy storage. In order to do this, the oscillating circuit on the secondary side of an inductive energy transfer system is short-circuited first, and the current and voltage system Evaluation was then made on the primary side and the secondary side. The coupling factor and the safety function of the secondary side can therefore be checked at the same time, and the measured values do not have to be exchanged between the primary side and the secondary side for this purpose.

10‧‧‧Removal device

11‧‧‧Feeding device

12‧‧‧One coil

15‧‧‧One-side communication device

20‧‧‧Control device

21‧‧‧Switching device

22‧‧‧second coil

25‧‧‧secondary communication device

26‧‧‧Rectifier

27‧‧‧Battery protection circuit

28‧‧‧ Energy storage

Claims (11)

A charging station (1) for inductive charging of an electrical energy storage device (28), comprising: a primary coil (12); a feeding device (11) designed to feed a predetermined test voltage or a predetermined test current Into the primary coil (12); measuring device (13, 14) designed to measure the feed current generated in the primary coil or the feed voltage generated in the primary coil; and release device (10) And is designed to release the inductive charging if the measured feed current drops below a predetermined primary side threshold or the measured feed voltage exceeds a predetermined primary side threshold. Charging process. A charging station (1) as claimed in claim 1, wherein the releasing device is designed to classify the fault based on the measured feed current or the measured feed voltage. A charging station (1) according to claim 1 or 2, wherein the feeding device (11) is designed to continuously increase the current in the primary coil (12) or the voltage across the primary coil (12) Until the predefined limit value for the voltage across the primary coil (12) or the current through the primary coil (12) is reached. A charging device (2) for inductive charging of an energy storage device (28), comprising: an oscillating circuit having a secondary coil (22); and a switching device (21) designed to electrically interconnect the oscillation Two connection points (A1, A2) of the circuit; a current measuring device (23) designed to measure an electrical test current in the secondary coil (22); and a control device (20) designed to control The switching device (21), and if in the secondary coil When the measured test current exceeds the predetermined secondary side threshold, the charging process for the inductive charging is released. A charging device (2) according to claim 4, comprising a voltage measuring device (24) designed to measure a first connection point (A1) and a second connection at the oscillating circuit Electrical test voltage between points (A2); wherein the control device (20) is when the switching device (21) is closed, only if the measured test voltage exceeds a predefined limit value for the test voltage , the charging process for the inductive charging is released. A charging device (2) according to claim 4 or 5, comprising a communication device (25) designed to have a first connection point (A1) and a second connection point of the oscillation circuit When (A2) is an electrical interconnection, the transmission is transmitted to the charging station (1). The charging device (2) of claim 6, wherein the communication device (25) is further designed to be used for the charging process if the control device (20) has released the charging process for inductive charging. The released information is transmitted to the charging station (1). A charging device (2) according to claim 6 wherein the communication device (25) is further designed to receive an initialization of the charging process from the charging station (1). A charging system for inductive charging of an energy storage device (28) in a carrier (3), comprising: a charging station (1) according to one of claims 1 to 3; and (3) having a charging device (2) as in one of claims 4 to 7. A method for inductive charging of an energy storage device (28), comprising the steps of short-circuiting (S1) an oscillating circuit having a secondary coil (22) by means of a switching device (21); Feeding a predetermined test voltage or predetermined test current (S2) to the primary coil (12); measuring (S3) the feed current generated in the primary coil (12) or the feed voltage generated on the primary coil (12) Measuring (S4) a test current generated in the secondary coil (22); if the measured test current exceeds a predetermined secondary side threshold and the measured feed current drops below a predetermined one-time side When the limit value or the measured feed voltage exceeds the predetermined primary side threshold, the inductive charging is released (S5). The method of claim 10, wherein the step of canceling the inductive charging (S5) is only if the voltage across the shorted oscillating circuit having the secondary coil (22) drops below a predefined limit voltage At this time, the inductive charging is released.