Electric vehicle detection for roadway wireless power transfer
AssigneeAuckland Uniservices Limited
InventorsGrant Anthony Covic, Abhilash Kamineni, Michael John Neath
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Abstract
A method of detecting a wirelessly powered vehicle on a roadway uses detection of induced voltages or currents in coils provided in the roadway. Once the vehicle has been detected the appropriate coils can be energised to power the vehicle.
Claims25
A method for supplying power to a vehicle on a path or roadway comprising a plurality of wireless power transfer coils, the method comprising:
- detecting a current or voltage induced in a de-energised wireless power transfer coil through mutual inductance with an energized wireless power transfer coil of the plurality of wireless power transfer coils;
- energising a wireless power transfer coil dependent on a property of the induced current or voltage to make power available to the vehicle;
- and
- at least one of:
- energizing a coil of the vehicle to induce free resonant currents in the de-energized wireless power transfer coil to indicate to the de-energized wireless power transfer coil information about a primary current desired by the vehicle;
- or
- energizing the coil of the vehicle to induce free resonant currents in the de-energized wireless power transfer coil to indicate that the vehicle is approaching the de-energized wireless power transfer coil.
A vehicle detection apparatus for detecting a vehicle on a path or roadway comprising a plurality of wireless charging modules, the apparatus comprising a detection circuit operable to detect a change in coupling between a second wireless charging module and a first wireless charging module due to the presence of the vehicle,
- wherein the apparatus is configured to detect, from the change in coupling between the second wireless charging module and the first wireless charging module due to the presence of the vehicle, the motion of the vehicle along the path or roadway, and to transfer power wirelessly to the vehicle via a coil of the vehicle as the coil of the vehicle passes over a wireless charging module based on the detected motion of the vehicle.
A method comprising detecting a change in coupling between at least two coils of a wireless charging apparatus, caused by an object situated between the at least two coils, by measuring a free resonant current induced in a first coil of the at least two coils by a second coil of the at least two coils, detecting a change in the free resonant current caused by the object situated between the at least two coils, and at least one of:
- energizing a coil of the object to induce free resonant currents in the first coil to indicate that the object is approaching the first coil;
- or
- switching a first converter of the wireless charging apparatus to cause the second coil of the at least two coils to make energy available for inductive power transfer at a first frequency, and switching a second converter of the wireless charging apparatus to cause the first coil of the at least two coils to be resonant at the first frequency while not making power available for inductive power transfer, wherein the method further comprises drawing, by the object situated between the at least two coils, at least 10 kW when the object is inductively coupled to at least one of the two coils.
Dependencies are inferred from the claim text.