System of inductive power transfer

{
  "publication_number": "US9837827B2",
  "country": "US",
  "kind": "B2",
  "title": "System of inductive power transfer",
  "abstract": "An inductive power transmitter comprises a first primary inductor configured to inductively couple a first secondary inductor and configured to hold a first variable electrical potential. The transmitter also comprises a second primary inductor configured to inductively couple a second secondary inductor that is configured to hold a second variable electrical potential. The primary inductors are arranged in an overlapping fashion on a substrate forming a charging surface. The first primary inductor is connected to a first driver capable of providing the first variable electrical potential, and the second primary inductor is connected to a second driver capable of providing the second variable electrical potential in a first embodiment while a second possibility is that the first primary inductor is connected to a first driver capable of providing the first variable electrical potential, and the second primary inductor comprises capacitor and is not connected to a driver.",
  "claims": [
    "1. An inductive power transmitter comprising: at least one first primary inductor configured to couple inductively with at least one first secondary inductor and configured to hold a first variable electrical potential, and at least one second primary inductor configured to couple inductively with at least one second secondary inductor and configured to hold a second variable electrical potential, wherein the first primary inductor and the second primary inductor are arranged in an overlapping fashion on a substrate forming a charging surface, and wherein the first variable electrical potential differs from the second variable electrical potential according to a parameter selected from the group consisting of a phase, a driving frequency, and a combination thereof wherein the first primary inductor is connected to a first driver capable of providing said first variable electrical potential, and the second primary inductor is connected to a second driver capable of providing said second variable electrical potential.",
    "2. The inductive power transmitter of claim 1, wherein the first primary inductor and the second primary inductor comprise a series of parallel segments connected in series in a square wave-like pattern, and wherein the first primary inductor and the second primary inductor are arranged such that the parallel segments of the first primary inductor and the second primary inductor alternate along one axis along the charging surface.",
    "3. The inductive power transmitter of claim 1, wherein, simultaneously, the first primary inductor is holding the first variable electrical potential and the second primary inductor is holding the first variable electrical potential.",
    "4. The inductive power transmitter of claim 1 capable of transmitting power from any location of said charging surface.",
    "5. The inductive power transmitter of claim 1 comprising a plurality of charging surfaces.",
    "6. The inductive power transmitter of claim 5, wherein the first primary inductor of a first charging surface is electrically connected to the first primary inductor of the remaining charging surfaces.",
    "7. The inductive power transmitter of claim 6, wherein the second primary inductor of a first charging surface is electrically connected to the second primary inductor of the remaining charging surfaces.",
    "8. The inductive power transmitter of claim 5, wherein each of the plurality of second primary inductors comprises at least one capacitor.",
    "9. An inductive power transmitter comprising: at least one first primary inductor configured to couple inductively with at least one first secondary inductor and configured to hold a first variable electrical potential, and at least one second primary inductor configured to couple inductively with at least one second secondary inductor and configured to hold a second variable electrical potential, wherein the first primary inductor and the second primary inductor are arranged in an overlapping fashion on a substrate forming a charging surface, and wherein the first variable electrical potential differs from the second variable electrical potential according to a parameter selected from the group consisting of a phase, a driving frequency, and a combination thereof, wherein the first primary inductor is connected to a first driver capable of providing said first variable electrical potential, and the second primary inductor comprises at least one capacitor and is not connected to a driver.",
    "10. The inductive power transmitter of claim 9, wherein the first primary inductor and the second primary inductor comprise a series of parallel segments connected in series in a square wave-like pattern, and wherein the first primary inductor and the second primary inductor are arranged such that the parallel segments of the first primary inductor and the second primary inductor alternate along one axis along the charging surface.",
    "11. The inductive power transmitter of claim 9, wherein, simultaneously, the first primary inductor is holding the first variable electrical potential and the second primary inductor is holding the first variable electrical potential.",
    "12. The inductive power transmitter of claim 9 capable of transmitting power from any location of said charging surface.",
    "13. The inductive power transmitter of claim 9 comprising a plurality of charging surfaces.",
    "14. The inductive power transmitter of claim 12, wherein the first primary inductor of a first charging surface is electrically connected to the first primary inductor of the remaining charging surfaces.",
    "15. The inductive power transmitter of claim 13, wherein the second primary inductor of a first charging surface is electrically connected to the second primary inductor of the remaining charging surfaces.",
    "16. The inductive power transmitter of claim 12, wherein each of the plurality of second primary inductors comprises at least one capacitor."
  ],
  "description_excerpt": "The embodiments disclosed herein relate to inductive power transfer systems. In particular, the embodiments relate to inductive power transmitters comprising at least two overlapping snake-shaped primary inductors, wherein the area encompassed by the primary inductors comprises no area with zero net magnetic field.\n\nTypically, in an inductive power transfer system, the primary inductor of the inductive power transmitter is in the shape of a coil. However a coil-shaped primary inductor is not optimal for creating a large charging surface. An inductive power transmitter with the primary inductor being a large-diameter coil has a flaw that the resulting magnetic field lacks uniformity and can vary in intensity over several orders of magnitude. The induced voltage generated in a small-diameter secondary inductor, when placed in the center region of the large-diameter primary inductor (weak magnetic field) compared to when placed near the edge of the same primary inductor, can potentially vary from 1 to 100 volts (depending of the specifications of the system). Further, the non-uniformity of the magnetic field becomes worse as the diameter of the primary inductor coil is increased. In addition, the extension of the magnetic field in the Z axis increases with the diameter of a coil-shaped primary inductor, which may or may not be desired.\n\nThus, an improved inductive power transfer system with an inductive power transmitter capable of transmitting power to an inductive power receiver with more uniformity across a wide area is desired.",
  "cpc": [
    "H01F 38/14",
    "H02J 5/005",
    "H02J 50/005",
    "H02J 50/10",
    "H02J 50/12",
    "H02J 50/50",
    "H02J 7/025",
    "H04B 5/0037",
    "H04B 5/0093",
    "H04B 5/266",
    "H04B 5/79"
  ],
  "ipc": [
    "H02J 4/25",
    "H02J 7/02",
    "H01F 38/14",
    "H02J 7/00",
    "H04B 5/00"
  ],
  "assignees": [
    "Powermat Technologies Ltd"
  ],
  "inventors": [
    "Amir Ben-Shalom"
  ],
  "filing_date": "2014-12-04",
  "publication_date": "2017-12-05",
  "grant_date": "2017-12-05",
  "priority_date": "2012-06-05",
  "application_number": "US-201414560189-A",
  "family_id": "49711502",
  "cited_by_count": 4,
  "citations": [
    "US20100219791A1",
    "US20090251102A1",
    "US8917057B2",
    "US7952322B2",
    "US20110221385A1",
    "US20100259217A1"
  ]
}