Abstract

A wireless power transmitting and charging system is disclosed. A method for operating a power transmission device of the wireless power transmitting and charging system comprises the steps of: maintaining a ping value table to which ping signal conditions are mapped according to the height of a power receiver; recognizing the power receiver by varying a ping signal according to the ping signal conditions recorded in the ping value table; and controlling a charging mode according to a message received from the power receiver.

IPC Classes  ?

• H02J 7/02 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries for charging batteries from AC mains by converters
• H02J 50/90 - Circuit arrangements or systems for wireless supply or distribution of electric power involving detection or optimisation of position, e.g. alignment
• H02J 50/40 - Circuit arrangements or systems for wireless supply or distribution of electric power using two or more transmitting or receiving devices
• H02J 50/12 - Circuit arrangements or systems for wireless supply or distribution of electric power using inductive coupling of the resonant type

Abstract

The present invention relates to a method and a device for adjusting the position of coils for adaptive coupling in a wireless power transmission system. A wireless power transmission system, according to the present invention, comprises: a wireless power transmission device having a primary coil for generating a magnetic field and transmitting wireless power; and a wireless power reception device having a secondary coil for receiving the wireless power by being coupled to the primary coil, wherein the wireless power transmission device sequentially discharges search pings while moving the primary coil, receives a signal strength packet that corresponds to each search ping, and moves the primary coil to a target position in which the coupling degree of the primary coil and secondary coil is equal to or higher than a fixed threshold value or is relatively the highest.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves
• H02J 7/02 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries for charging batteries from AC mains by converters
• H01F 38/14 - Inductive couplings
• H02J 5/00 - Circuit arrangements for transfer of electric power between ac networks and dc networks
• H04B 5/00 - Near-field transmission systems, e.g. inductive or capacitive transmission systems

Abstract

The present description relates to a wireless power transmission/reception device. The present description provides a magnetic field controlling member for focusing a magnetic field between a primary coil, which is connected to a power source of a wireless power transmission system and forms a magnetic field, and a secondary coil which is for receiving power by means of the magnetic field. The magnetic field controlling member comprises: a substrate, between the primary coil and secondary coil, of which one side faces the primary coil or secondary coil; a pattern unit which is placed on the substrate and has a plurality of thin films that are positioned at a predetermined distance away from each other; and a connecting unit which electrically connects the plurality of thin films.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves
• H02J 7/02 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries for charging batteries from AC mains by converters
• H01F 38/14 - Inductive couplings

Abstract

A wireless power transmission device, and a transmission power control method therefor are provided. A wireless power transmission device for wirelessly transmitting power to a wireless power receiving device can comprise: a primary core comprising at least one primary coil and transmitting a power signal to the wireless power receiving device by being coupled, through magnetic induction or magnetic resonance, to a secondary core provided at the wireless power receiving device; an inverter connected to the primary core so as to apply an alternating voltage necessary for transmitting the power signal; and a controller connected to the inverter, and controlling a direct voltage to be applied to the wireless power transmission device and/or a gate voltage of the inverter on the basis of the information on the power received at the wireless power receiving device by the power signal.

IPC Classes  ?

• H02J 50/12 - Circuit arrangements or systems for wireless supply or distribution of electric power using inductive coupling of the resonant type
• H02J 50/40 - Circuit arrangements or systems for wireless supply or distribution of electric power using two or more transmitting or receiving devices
• H02J 7/00 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries

Abstract

The present specification relates to a wireless power transmission device. The present specification provides a wireless power transmission device comprising: a power supply unit for supplying power to the wireless power transmission device; at least one first coil for transmitting power to a wireless power reception device; and first and second condensers configured so as to be connected respectively to different both ends of the power supply unit and the first coil.

IPC Classes  ?

• H02J 50/12 - Circuit arrangements or systems for wireless supply or distribution of electric power using inductive coupling of the resonant type
• H02J 50/40 - Circuit arrangements or systems for wireless supply or distribution of electric power using two or more transmitting or receiving devices
• G01R 19/00 - Arrangements for measuring currents or voltages or for indicating presence or sign thereof

Abstract

A coil structure for wireless power transmission is provided. The coil structure comprises: a primary resonance coil wound in a spiral shape around a centripetal point; a primary induction coil, which supplies power to the primary resonance coil in a non-connected state with an input or output terminal of the primary resonance coil and is wound in a spiral shape on a substantially same plane around a substantially same centripetal point as the centripetal point; a switch configured to be parallel with the primary resonance coil so as to control the ON and OFF of an operation of the primary resonance coil; and a capacitor coupled to the primary resonance coil so as to form a magnetic resonance with the primary resonance coil.

IPC Classes  ?

• H02J 50/12 - Circuit arrangements or systems for wireless supply or distribution of electric power using inductive coupling of the resonant type
• H02J 50/40 - Circuit arrangements or systems for wireless supply or distribution of electric power using two or more transmitting or receiving devices
• H01F 38/14 - Inductive couplings
• H02J 7/00 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries

Abstract

An apparatus and a method for controlling the power transmission coverage of a wireless power transmission network are disclosed. The method for controlling the power transmission coverage of a wireless power transmission network, which includes a plurality of peripheral devices for receiving power from a main device through a resonant channel within the power transmission coverage of the main device, comprises the steps of: checking a wireless power transmission network disconnection state of any one of the plurality of peripheral devices by a procedure gradually decreasing the amount of transmission power of the main device; and forming the power transmission coverage on the basis of the amount of transmission power at the moment of the wireless power transmission network disconnection.

IPC Classes  ?

• H02J 50/00 - Circuit arrangements or systems for wireless supply or distribution of electric power
• H02J 7/00 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries

Abstract

A method and an apparatus for controlling power in a wireless power transfer system are disclosed. A method for controlling power of a main device in a wireless power transfer system comprises the steps of: receiving information necessary for power control from a plurality of peripheral devices; identifying the actual power consumption state of the plurality of peripheral devices on the basis of the information necessary for power control, and determining a reference peripheral device on the basis of the actual power consumption state; and determining output power in consideration of the reference peripheral device.

IPC Classes  ?

• H02J 50/00 - Circuit arrangements or systems for wireless supply or distribution of electric power
• H02J 7/00 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries

Abstract

Disclosed is a wireless power transmission and charging system comprising at least one of a coil array, a hybrid transmission unit, a means for protection against overheating or for detection of foreign matter by means of a temperature or pressure sensor, and a power control unit.

IPC Classes  ?

• H02J 50/00 - Circuit arrangements or systems for wireless supply or distribution of electric power
• H02J 7/00 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• H02J 7/02 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries for charging batteries from AC mains by converters

Abstract

Provided is a wireless power transmission and charging system. The wireless power transmission and charging system comprises at least one of: a coil array; a hybrid transmission unit; a feature for protecting against overheating by means of a temperature or pressure sensor, or for sensing foreign matter; and a power control unit.

IPC Classes  ?

• H02J 50/00 - Circuit arrangements or systems for wireless supply or distribution of electric power
• H02J 7/02 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries for charging batteries from AC mains by converters
• H02J 7/00 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries

Abstract

The present invention provides a battery pack comprising: a bare cell; a protection circuit board connected to the bare cell so as to control the charging and discharging of the bare cell; a coupling plate including an insulating body disposed between the bare cell and the protection circuit board so as to support the protection circuit board, and a welding member connected to the insulating body and welded to the bare cell; and a protective cap disposed so as to cover the protection circuit board and the coupling plate.

IPC Classes  ?

• H01M 2/34 - Current-conducting connections for cells with provision for preventing undesired use or discharge
• H01M 2/02 - Cases, jackets or wrappings
• H01M 10/46 - Accumulators structurally combined with charging apparatus

Abstract

A wireless power reception device and a wireless communication method thereby are provided. The wireless communication method by the wireless power reception device may comprise the steps of: receiving a wireless power signal from a wireless power transmission device; measuring the strength of the wireless power signal; modulating the amplitude of the wireless power signal according to the measured strength of the wireless power signal; and performing communication with the wireless power transmission device by using the signal having the amplitude modulated.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves
• H02J 7/00 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries

Abstract

A wireless power reception device and a wireless communication method thereby are provided. The wireless communication method by the wireless power reception device may comprise the steps of: receiving a wireless power signal from a wireless power transmission device; measuring the strength of the wireless power signal; modulating the amplitude of the wireless power signal according to the measured strength of the wireless power signal; and performing communication with the wireless power transmission device by using the signal having the amplitude modulated.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves
• H02J 7/00 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• H03C 1/16 - Amplitude modulation by means of discharge device having at least three electrodes

Abstract

The present invention provides a wireless power transmission apparatus for a vehicle, comprising: a base unit structured to be inserted into a cup holder of the vehicle; a cradle unit including a cradle housing, which has a cradle surface formed to be inclined with respect to the center axis of the base unit and on which a wireless power receiving apparatus is cradled and a support surface bent and extended from the cradle surface, and a compression member installed in the cradle housing and pressing the wireless power receiving apparatus such that the wireless power receiving apparatus is compressed toward the cradle surface, wherein the cradle unit is connected to the base unit; and a transmission unit embedded in the cradle unit, and receiving power from a battery of the vehicle so as to output a wireless power signal to the wireless power receiving apparatus.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves
• H02J 7/00 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• H05K 9/00 - Screening of apparatus or components against electric or magnetic fields
• B60N 3/00 - Arrangements or adaptations of other passenger fittings, not otherwise provided for

Abstract

The present invention provides a wireless power transmission apparatus installable on a wall, the wireless power transmission apparatus comprising: a housing configured to allow a wireless power reception apparatus to be placed thereon; a plug, a part of which is embedded in the housing, the plug being configured to be coupled with a socket for alternating current power installed on a wall; and a transmission unit which is embedded in the housing, converts an alternating current power supplied from the plug to a direct current power, and outputs a wireless power signal to the wireless power reception apparatus.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves

Abstract

The present invention relates to a low-heat type wireless power reception device comprising: a power reception coil for receiving a wireless power signal; an impedance matching unit for matching the impedance such that the power reception coil is resonant to the wireless power signal; a rectifying unit for rectifying the wireless power signal so as to convert the signal into direct current power; a power converting unit which includes a low-heat transformer unit having a first resistance value and a high-heat transformer unit having a second resistance value larger than the first resistance value, wherein the transformer units are connected in parallel with each other and supply output power of the rectifying unit to a load as charging power; and a reception control unit which controls the impedance matching of the impedance matching unit, and which supplies the charging power to the load by selectively turning on and off the low-heat transformer unit in a state where the high-heat transformer unit is continuously turned on.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves

Abstract

The present invention relates to a power control method and device in a wireless power transmission system. According to the present invention, even if a CEP packet is not transmitted from a wireless power reception device over a certain period of time, a wireless power transmission device may additionally determine whether the wireless power reception device is located in a charging area and sustainably perform charging.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves

Abstract

The present invention relates to a wireless power transmission device capable of simultaneously performing multi-charge, the wireless power transmission device comprising: a plurality of transmission blocks comprising two or more first coils; and a transmission control unit for, when a plurality of wireless power reception devices are placed in charging locations, selecting a plurality of first coils which correspond to the wireless power reception devices, using response signals from first coils, which correspond to the charging locations, and controlling the transmission blocks such that wireless power signals are simultaneously transmitted by the selected plurality of first coils.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves
• H02J 7/00 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries

Abstract

The present invention relates to a signal processing method in a hybrid wireless power transmission apparatus and a hybrid wireless power transmission apparatus using the same, which can transmit a wireless power signal of a magnetic resonance scheme and a wireless power signal of an induction scheme. The signal processing method of the present invention comprises the steps of: oscillating alternately a first object detection signal through an inductive power transmission unit and a second object detection signal through a magnetic resonance power transmission unit; selecting and operating one of the inductive power transmission unit and the magnetic resonance power transmission unit on the basis of an induced response signal and a resonance response signal corresponding to the first object detection signal and the second object detection signal; and transmitting a wireless power signal via the selected power transmission unit.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves

Abstract

A wireless power transmission device for a vehicle and a wireless charging method are provided. The wireless charging method by the wireless power transmission device for a vehicle can comprise the steps of: transmitting a signal for detection of a wireless power reception device by using a lower frequency band than an operating frequency band used to control the vehicle; receiving a response signal to the transmitted signal and a power control signal from the wireless power reception device; controlling an operating frequency and/or a voltage in the wireless power transmission device for the vehicle according to the power control signal; and transmitting wireless power to the wireless power reception device.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves
• H02J 7/00 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• B60R 16/02 - Electric or fluid circuits specially adapted for vehicles and not otherwise provided forArrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for electric

Abstract

The present invention provides a wireless power transmission apparatus and a vehicle equipped with the same, the wireless power transmission apparatus comprising: a transmission unit for transmitting a wireless power signal to a wireless power reception apparatus; and an upward driving unit for driving the transmission unit upward.

IPC Classes  ?

• H01F 38/14 - Inductive couplings
• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves

Abstract

The present invention relates to a wireless power reception apparatus which can supply power via cables to multiple external devices, the wireless power reception apparatus comprising: a reception coil for receiving a wireless power signal from a wireless power transmission apparatus and generating AC power; a rectification unit for rectifying the AC power to DC power; and a plurality of connector units for transferring, to the external devices, the DC power from the rectification unit.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves
• H02J 7/00 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries

Abstract

The present invention provides a receptacle-type wireless power transmitting device comprising: a body having a hollow receiving part of a size capable of accommodating a wireless power receiving device; a transmission unit configured to transmit a wireless power signal to the wireless power receiving device, accommodated in the receiving part, by using an input power; and a power supply unit configured to supply the input power to the transmission unit.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves
• H02J 7/00 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries

Abstract

The present invention relates to a wireless power transmission device having an advertising function, the device comprising: a transmission coil configured to transmit a wireless power signal; a memory configured to store advertising information; a display unit for displaying the advertising information, the display unit being installed on one side of the transmission coil; and a transmission control unit for displaying, on the display unit, the advertising information stored in the memory and controlling the wireless power signal to be transmitted to a wireless power receiving device via the transmission coil when the wireless power receiving device is placed in a charging location.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves

Abstract

The present invention relates to a low-heat wireless power apparatus and a method therefor, wherein a battery is charged with low heat by receiving a wireless power signal transmitted by a wireless power transmission apparatus, and a controller matches impedance by controlling an impedance matching/controller when a power receiving coil receives the wireless power signal. In addition, the controller determines the charging load status of a power receiving apparatus according to the time spent for supplying power to the power receiving apparatus and the current level detected by a current detection part, and minimizes the generation of heat and supplies power to the power receiving apparatus by selectively turning on a low-heat transformation part and a high-heat transformation part according to the determined charging load status.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves

Abstract

The present invention relates to a method for controlling a wireless power transmission in a resonant wireless power transmission system, to a wireless power transmitting apparatus using same, and to a wireless power receiving apparatus using same. The method comprises the steps of: receiving a start signal from the wireless power receiving apparatus; and activating the power block which has been inactivated and transmitting a wireless power transmission signal to the wireless power receiving apparatus via a transmission coil of the wireless power transmitting apparatus upon receipt of the start signal.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves

Abstract

The present invention relates to a method for providing compatibility with a wireless power transmitting device in a wireless power transmitting system. The method includes the steps of: detecting a wireless power receiving device on the basis of a load change; transmitting a request signal for requesting information for a receiving device to the wireless power receiving device; receiving the information for the receiving device from the wireless power receiving device, wherein the information selectively includes version information on standard technical specifications for realizing the wireless power receiving device; and, when the version information is included in the information for the receiving device, performing a wireless power transmitting operation according to the standard technical specifications corresponding to the version information.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves

Abstract

The present invention relates to a wireless power transmission device, wherein a user can wirelessly transmit power to a power receiving device by high transmission efficiency regardless of time and place by simply carrying the wireless power transmission device, and the wireless power transmission device comprises: a power storage unit which stores direct current power; and a power transmission unit which operates by the direct current power stored in the power storage unit, and wirelessly transmits power to the power receiving device.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves

Abstract

The present invention relates to a coil resonant coupler for short range wireless power tranmission and an apparatus for transmitting short range wireless power containing the same, wherein the coil resonant coupler for short range wireless power transmission comprises: a first coil which is vertically formed to a first shaft; a second coil which is vertically placed to a second shaft vertical to the first shaft; and a third coil which is vertically placed to a third shaft vertical to the first and second shafts, respectively.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves
• H02J 7/00 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries

Abstract

The present invention relates to a core assembly for wireless power communication and to a power supply device for wireless power communication including same, and to a method for manufacturing a core assembly for wireless power communication. The core assembly for wireless power communication includes a recess at a cylindrical surface, a plate-shaped core made of a magnetic substance, a plurality of wound coils received in the recess and disposed such that one portion of each overlaps another, and a circuit substrate connected to both ends of the coil to apply power to the coil.

IPC Classes  ?

• H01F 27/26 - Fastening parts of the core togetherFastening or mounting the core on casing or support
• H01F 41/02 - Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformersApparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils or magnets
• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves

Abstract

The present invention relates to a method for changing the reception mode in a mobile communication terminal and to a mobile communication terminal using same. The method includes: confirming whether the reception mode of the mobile communication terminal is a vibration mode; and changing the vibration mode to a non-vibration mode when the reception mode of the mobile communication terminal is the vibration mode.

IPC Classes  ?

• H04B 1/40 - Circuits
• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves

Abstract

The present invention relates to a power receiver for wireless charging, and a portable electronic device having same, wherein the power receiver comprises: a body defining a housing; a coil removably housed in the housing and formed so as to receive power by being magnetically coupled to a power supplying device; and a charging kit including a charging circuit configured to charge a battery through induced electromotive force induced by the coil.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves
• H02J 7/00 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries

Abstract

The present invention relates to a contactless power receiving device and a jig for the manufacture of a core for the receiving device. More specifically, both a power receiving coil of a charging system and a loop antenna of an electronic payment system are mounted in the battery pack and cover case of a portable terminal, with the power receiving coil being positioned at the central portion and the loop antenna being positioned on the outskirts, and a receiving mode of a wireless power signal and a transmitting/receiving mode of data are then executed selectively. As such, impact of interference caused by harmonics is eliminated in advance, and contactless charging as well as electronic payment can be performed through one portable terminal. Particularly, there are provided diverse layouts for the control modules of the contactless charging system using the wireless power transmission/receiving technique and of the electronic payment system using near-field communication, and a jig for the manufacture of a coil with merits of both the circular and rectangular coils. Thus, the reliability for a contactless charging system is improved, which leads to easier manufacturing and sales of portable terminals, battery packs, etc., and an increased competitiveness of such products.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves
• H01F 41/06 - Coil winding

Abstract

The present invention relates to a contactless power transmission device. In particular, the contactless power transmission device used for supplying electric energy in a wireless power transmission mode senses an object placed on its charging deck, and enables power transmission and data communication only when a contactless power receiving device is placed into position to be able to recognize the state of a receiving side accurately and control the power in an efficient manner. In addition, the contactless power transmission device of the invention measures power supplied to the contactless power receiving device, and controls output power of wireless power signals that are sent from two different cores, as a result of which stable charging performances can be provided and, especially, stable power supply is ensured even if the contactless power receiving device moves on the contactless power transmission device. Accordingly, the reliability for a contactless charging system comprising a contactless power receiving device and a contactless power transmission device can be improved, and the competitiveness of products related to portable terminals, battery packs, etc. can be increased.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves
• H02J 7/00 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries

Abstract

There is provided a wireless charger system for a battery pack solution that is provided so that a wireless charger system composed of a wireless charger apparatus and a battery pack can supply a power source to a portable terminal block through the wireless power transmission. The wireless charger apparatus 10 according to the present invention includes a power receiver block 12; a resonant converter 14 for converting an output signal and supplying the converted output signal to the charging power transmitter block 15, the output signal including a power signal and a data signal, both of which are supplied from the power receiver block 12; a gate driver 13 coupled to the power receiver block 12 to transmit an output signal including a data signal and a power signal to the resonant converter 14, controlled by the central controller 11 and provided with a bootstrap gate drive; a current detector block 16 coupled between the power receiver block 12 and the resonant converter 14 to detect a data signal of the battery pack 20; a central controller 11 for controlling the power receiver block 12, the resonant converter 14, the gate driver 13 and the current detector block 16; and a display block 19 for displaying a state of the wireless charger apparatus 10 according to the control signal of the central controller 11.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves

Abstract

Disclosed is a non-contact charger. The present invention provides a non-contact charger capable of wireless data communication and power supply between a non-contact charger capable of computer USB communication and a charging battery-pack of a mobile device, using an induced electromotive force, thereby to enable data communication and power supply at the same time and to make good signal transmission without other poor contacts in the contact transmission.

IPC Classes  ?

• H02J 17/00 - Systems for supplying or distributing electric power by electromagnetic waves