Non-contact power feeding coil and non-contact power feeding system
A power feeding coil that configures a non-contact power feeding system is provided. The power feeding coil is provided with a coil through which an AC current of a specific frequency flows, and a core that forms a section of a circulating magnetic path, which is interlinked with the coil. In the coil, a wire having an insulating covering is wound around a conductor, and a covering thickness of the insulating covering is set so that the influence of a proximity effect that occurs at the specific frequency between adjacent portions of the wire is a predetermined amount or less. According to this configuration, it is possible to freely adjust a separation distance between portions of the conductor by altering the covering thickness; and the occurrence of AC loss caused by a proximity effect may be appropriately suppressed.
1. A non-contact power feeding coil that is used in at least one of a power feeding coil and a power receiving coil that configure a non-contact power feeding system, the non-contact power feeding coil comprising:
a coil through which an AC current of a specific frequency flows; and
a core that forms a section of a circulating magnetic path, which is interlinked with the coil,
wherein in the coil, a wire having an insulating covering is wound around a conductor, and the wire is wound around, in a parallel manner, an opposing intermediate face when the power feeding coil and the power receiving coil oppose one another,
wherein the core has a center leg section that is fitted into a hollow section at the center of the coil, a side leg section that covers an outer peripheral section of the coil, and a bottom face section that covers an end face section on a side that is separated from the opposing intermediate face of the coil,
wherein a plurality of the coils for non-contact power supply are used in a manner of being aligned in a predetermined direction, and
wherein the side leg section of the core covers, among an outer peripheral section of the coil, a partial range that is parallel to the predetermined direction and does not cover a remaining range that intersects the predetermined direction.
2. The non-contact power feeding coil according to claim 1 ,
wherein a cross-sectional area of the conductor of the wire is based on a coil resistance value, the coil resistance value being obtained by adding a DC resistance value of the coil, and an AC resistance value of the coil which is a resistance increment caused by a skin effect that occurs at the specific frequency.
3. The non-contact power feeding coil according to claim 1 ,
wherein the conductor is a composite conductor composed of a plurality of wires, or a single conductor composed of a single wire.
4. A non-contact power feeding system comprising:
a power feeding coil provided in a power feeding unit;
an AC power supply circuit that supplies AC power of the specific frequency to the power feeding coil;
a power receiving coil that is provided in a power receiving unit, the power receiving coil electrically coupling with and receiving AC power in a non-contact manner when opposing the power feeding coil; and
a power receiving circuit that converts AC power received by the power receiving coil, generates a drive voltage, and outputs the drive voltage to an electrical load,
wherein the power feeding coil is the non-contact power feeding coil according to claim 1 , and
the power receiving coil includes a coil through which an AC current of the specific frequency flows and a core that forms a section of a circulating magnetic path, which is interlinked with the coil, the coil is composed of a plurality of coil blocks in which wires having insulating coverings around conductors are respectively wound, and further includes a bobbin having a main partition section that partitions the coil and the core, and an inter-block partition section that partitions the plurality of coil blocks.
5. The non-contact power feeding system according to claim 4 ,
wherein an identical number of the power feeding units are provided in a plurality of board production machines that configure a board production line, and the power receiving unit is provided in a moving body that moves in a linear arrangement direction of the plurality of board production machines.