An electronic device in a wireless power system may be operable with a removable accessory such as a case. The device may have coplanar power transmitting and power receiving coils. The transmitting coil may be positioned within a central opening of the receiving coil. The removable accessory may have an embedded receiving coil configured to receive wireless power from the transmitting coil of the electronic device. The receiving coil of the electronic device may receive wireless power from a power transmitting device such as charging mat. The receiving coil of the electronic device may operate up to a higher maximum power than the transmitting coil of the electronic device. The power transmitting coil and power receiving coil in the electronic device may operate at different power transmission frequencies. To mitigate crosstalk, the power transmitting coil's operation frequency may be a non-integer multiple of the power receiving coil's operation frequency.

An electric power converter includes an electric gatedriver circuit that includes a transformer. The transformer includes separate first and second cores of magnetically conductive material that are shaped to form respective closed loops. The transformer also includes a first electrical conductor with at least one winding arranged around a part of the first core in a first winding direction and at least one winding arranged around a part of the second core in a second winding direction opposite the first winding direction. The transformer further includes a second electrical conductor with at least one winding arranged around a part of the first core in the first winding direction and at least one winding arranged around a part of the second core in the second winding direction so as to counteract electric influence induced by a common magnetic field through the closed loops of the first and second cores.

An electric power converter includes an electric gatedriver circuit that includes a transformer. The transformer includes separate first and second cores of magnetically conductive material that are shaped to form respective closed loops. The transformer also includes a first electrical conductor with at least one winding arranged around a part of the first core in a first winding direction and at least one winding arranged around a part of the second core in a second winding direction opposite the first winding direction. The transformer further includes a second electrical conductor with at least one winding arranged around a part of the first core in the first winding direction and at least one winding arranged around a part of the second core in the second winding direction so as to counteract electric influence induced by a common magnetic field through the closed loops of the first and second cores.

A coil component includes a winding core that includes a winding core portion, a first flange portion, and a second flange portion. The coil component further includes a plate core that has a main surface facing the winding core portion, the first flange portion, and the second flange portion, that extends between the first flange portion and the second flange portion, and that is secured to the winding core by using adhesive. Each of the first flange portion and the second flange portion has an upper surface that faces the main surface of the plate core. Recessed portions are formed on the corresponding upper surfaces. Protrusions may be formed in corresponding regions in which the recessed portions are formed.

Systems and methods for improving winding losses in transformers are disclosed. In one aspect, a transformer includes a first magnetic core having an interior portion and an exterior portion, a second magnetic core in contact with the interior and exterior portions, a plurality of primary and secondary windings formed around the interior portion, where the interior portion is formed from one of a first magnetic material and a second magnetic material, and the exterior portion is formed from one of the first magnetic material and the second magnetic material, where the first magnetic material has different properties than the second magnetic material. In another aspect, the first magnetic core includes a third portion that extends across and is in contact with the interior portion and the exterior portion, where the third portion is formed from one of the first magnetic material and the second magnetic material.

Systems and methods for improving winding losses in transformers are disclosed. In one aspect, a transformer includes a first magnetic core having an interior portion and an exterior portion, a second magnetic core in contact with the interior and exterior portions, a plurality of primary and secondary windings formed around the interior portion, where the interior portion is formed from one of a first magnetic material and a second magnetic material, and the exterior portion is formed from one of the first magnetic material and the second magnetic material, where the first magnetic material has different properties than the second magnetic material. In another aspect, the first magnetic core includes a third portion that extends across and is in contact with the interior portion and the exterior portion, where the third portion is formed from one of the first magnetic material and the second magnetic material.

The present disclosure concerns a magnetic component (1), especially for a wireless charging transformer, including a magnetic core (2), at least one flat pre-wound major electrical coil (3) disposed on the magnetic core (2) and at least one minor electrical coil (4) wound around the magnetic core (2). The present disclosure also concerns a transformer (100) including the magnetic component (1) as a primary magnetic component (101).

A contactless electrical energy transfer device including a first system which includes at least one first coil including at least one first winding around at least one first zone without wire, a layer of ferromagnetic elements, at least one small column passing through the first coil by passing through a first zone without wire, and a second system which includes at least one second coil including at least one second winding around at least one second zone without wire. The small column or columns make it possible to optimize the magnetic coupling coefficient despite the absence of a layer of ferromagnetic elements in the second system. Also, a flying vehicle fitted with rechargeable batteries and its recharging base, both equipped with the electrical energy transfer device are provided.

A contactless electrical energy transfer device including a first system which includes at least one first coil including at least one first winding around at least one first zone without wire, a layer of ferromagnetic elements, at least one small column passing through the first coil by passing through a first zone without wire, and a second system which includes at least one second coil including at least one second winding around at least one second zone without wire. The small column or columns make it possible to optimize the magnetic coupling coefficient despite the absence of a layer of ferromagnetic elements in the second system. Also, a flying vehicle fitted with rechargeable batteries and its recharging base, both equipped with the electrical energy transfer device are provided.

A coil component includes a first coil and a second coil that magnetically couples with the coil and causes a negative inductance to be generated. The coil component further includes an electrode that is provided at a position adjacent to or in the vicinity of a port of each of the first and second coils.