WIRELESS POWER TRANSFER SYSTEM
A wireless power transfer system including a power transmitter and power receiver including magnetically permeable cores having a base portion and an axial core portion extending away therefrom with windings provided upon the axial core portion. The arrangement is particularly suited for use in wireless power connectors.
1 . A wireless power transfer system including:
a. a power transmitter including:
i. a magnetically permeable transmitter core having a base portion and an axial core portion extending away therefrom along a magnetic field propagation axis, wherein the base portion extends further away from the magnetic field propagation axis than the axial core portion;
ii. transmitter windings provided about the axial core portion; and
iii. an AC power supply driving the windings to produce an oscillating magnetic field; and
b. a power receiver including:
i. a magnetically permeable receiver core having a base portion and an axial core portion extending away therefrom along a magnetic field reception axis, wherein the base portion extends further away from the magnetic field reception axis than the axial core portion;
ii. receiver windings provided about the axial core portion; and
iii. a power receiver circuit receiving an AC current from the windings induced by the oscillating magnetic field.
2 . A wireless power transfer system as claimed in claim 1 , wherein the base portion of the transmitter core is a disk.
3 . A wireless power transfer system as claimed in claim 1 , wherein the base portion of the transmitter core includes at least one discontinuity to inhibit eddy currents.
4 . A wireless power transfer system as claimed in claim 3 wherein the discontinuity extends from an edge of the base portion of the transmitter core towards its centre.
5 . A wireless power transfer system as claimed in claim 4 wherein the opening is in the form of a slot having a radiused termination.
6 . A wireless power transfer system as claimed in claim 3 wherein the discontinuity is in the form of an opening that allows access from one side of the base portion of the transmitter core, remote from the axial core portion, to the other side, proximate the axial core portion.
7 . A wireless power transfer system as claimed in claim 1 , wherein the base portion and axial core portion of the transmitter core include a channel to permit a communications component to pass from one side of the transmitting core to another side of the transmitting core.
8 . A wireless power transfer system as claimed in claim 1 , wherein the base portion and an axial core portion of the transmitter core are separate pieces.
9 . A wireless power transfer system as claimed in claim 1 wherein the magnetically permeable transmitter core includes a outer portion extending from the base portion about the axial portion, wherein the axial portion extends further from the base than the outer portion.
10 . A wireless power transfer system as claimed in claim 9 , wherein the axial portion extends at least 20 percent further from the base than the outer portion.
11 . A wireless power transfer system as claimed in claim 10 wherein the base portion includes an opening that allows access from one side of the base portion of the transmitter core, remote from the axial portion, to a space between the axial portion and outer portion of the transmitter core.
12 . A wireless power transfer system as claimed in claim 1 , wherein the base portion of the receiver core is a disk.
13 . A wireless power transfer system as claimed in claim 1 , wherein the base portion of the receiver core includes at least one discontinuity to inhibit eddy currents.
14 . A wireless power transfer system as claimed in claim 13 wherein the discontinuity extends from an edge of the base portion of the receiver core towards its centre.
15 . A wireless power transfer system as claimed in claim 14 wherein the opening is in the form of a slot having a radiused termination.
16 . A wireless power transfer system as claimed in claim 13 wherein the discontinuity is in the form of an opening that allows access from one side of the base portion of the receiver core, remote from the axial core portion, to the other side, proximate the axial core portion.
17 . A wireless power transfer system as claimed in claim 1 , wherein the base portion and axial core portion of the receiver core include a channel to permit a communications component to pass from one side of the of the receiver core to another side of the of the receiver core.
18 . A wireless power transfer system as claimed in claim 1 , wherein the base portion and an axial core portion of the receiver core are separate pieces.
19 . A wireless power transfer system as claimed in claim 1 wherein the magnetically permeable receiver core includes an outer portion extending from the base portion about the axial portion, wherein the axial portion extends further from the base than the outer portion.
20 . A wireless power transfer system as claimed in claim 19 , wherein the axial portion extends at least 20 percent further from the base than the outer portion.
21 . A wireless power transfer system as claimed in claim 19 wherein the base portion includes an opening that allows access from one side of the base portion of the receiver core, remote from the axial portion, to a space between the axial portion and outer portion.
22 . A wireless power transfer system as claimed in claim 1 , wherein the power transmitter core and windings are contained within a first wireless power connector and the power receiver core and windings are contained within a second wireless power connector and wherein the connectors are interconnectable so as to align the magnetic field propagation and reception axes.
23 . A wireless power transfer system as claimed in claim 1 , wherein one or more core includes a graduated transition between the base portion and the axial core portion where the direction of the main magnetic flux path changes.
24 . A wireless power transfer system as claimed in claim 1 , wherein both the transmitter and receiver cores include a graduated transition between the base portion and the axial core portion where the direction of the main magnetic flux path changes.
25 . A wireless power transfer system as claimed in claim 23 , wherein each graduated transition is in the form of a curve.
26 . A wireless power transfer system as claimed in claim 23 , wherein each graduated transition is in the form of one or more straight transition sections disposed at an angle with respect to the base portion and axial core portion.
27 . A wireless power transfer system as claimed in claim 26 , wherein the angle is about 45 degrees.
28 . A magnetically permeable core for use in a wireless power transfer system, including a base having first and second portions extending away therefrom, wherein the first portion extends further from the base than the second portion such as to maintain an effective flux linkage throughout a range of relative displacement of a receiving core from a transmitting core and wherein the core includes one or more graduated transitions between the base portion and the axial core portion where the direction of the main magnetic flux path changes
29 . A core as claimed in claim 28 , wherein each graduated transition is in the form of a curve.
30 . A core as claimed in claim 28 , wherein each graduated transition is in the form of one or more straight transition sections disposed at an angle with respect to the base and first or second core portions.
31 . A core as claimed in claim 30 , wherein the angle is about 45 degrees.