Patent Application
20190351774
This disclosure generally relates to power transfer system, and more particularly relates to power transfer system for charging an electric vehicle.
The present invention will now be described, by way of example with reference to the accompanying drawings, in which:
Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the various described embodiments. However, it will be apparent to one of ordinary skill in the art that the various described embodiments may be practiced without these specific details. In other instances, well-known methods, procedures, components, circuits, and networks have not been described in detail so as not to unnecessarily obscure aspects of the embodiments.
The system 10 includes a positioning-device 16 that is configured to determine a position 18 of the vehicle 12 moving within the power-transfer-zone 14. In the example illustrated in
The system 10 also includes a base-coil 22 disposed within the power-transfer-zone 14 configured to emit a magnetic-field 24 in response to electrical power 26 applied to the base-coil 22. The base-coil 22 (also referred to as a ground-coil or ground-assembly), may be any base-coil 22 suitable for transferring energy to the vehicle 12 and preferably conforms to an SAE Recommended Practice J2954 NOV2017 specification. The base-coil 22 includes a power-supply and corresponding control-devices required to generate the magnetic-field 24. In general, a strength of the magnetic-field 24 increases with increasing electrical power 26 applied to the base-coil 22. Additionally, the strength of the magnetic-field 24 is greatest proximate to the base-coil 22, and generally varies inversely with the third-power of distance away from the base-coil 22.
The system 10 also includes one or more controller-circuits 28 in communication with the positioning-device 16 and the base-coil 22. As illustrated in
The system 10 further includes a vehicle-coil 32 installed on the vehicle 12 and in communication with the one or more controller-circuits 28. The vehicle-coil 32 (also referred to as a vehicle-assembly) may be any vehicle-coil 32 suitable for receiving energy from the base-coil 22, and preferably conforms to the SAE Recommended Practice J2954 NOV2017 specification. In the examples illustrated in
In another embodiment, the one or more controller-circuits 28 further control the electrical power 26 applied to the base-coil 22 based on a vehicle-coil-position 36 (see
Step 202, DETERMINE POSITION, includes determining a position 18 of a vehicle 12 moving within a power-transfer-zone 14 with a positioning-device 16 as described above.
Step 204, DETERMINE VEHICLE OVERLAY, includes determining, with the positioning-device 16, whether any portion of the vehicle 12 overlays a base-coil 22 disposed within the power-transfer-zone 14 as described above.
Step 206, CONTROL POWER, includes controlling electrical power 26 applied to the base-coil 22, with one or more controller-circuits 28 in communication with the positioning-device 16 and the base-coil 22, such that the base-coil 22 immediately emits a magnetic-field 24 characterized as having value of greater than 27 microteslas (27 μT) as described above. The system 10 further includes a vehicle-coil 32 installed on the vehicle 12 and in communication with the one or more controller-circuits 28 that generates a sensed-voltage 34 in response to the magnetic-field 24 emitted by the base-coil 22. The one or more controller-circuits 28 may control the electrical power 26 to the base-coil 22 based on a vehicle-coil-position 36 within the power-transfer-zone 14 when the vehicle 12 overlays the base-coil 22. The one or more controller-circuits 28 may also control the electrical power 26 to the base-coil 22 such that the vehicle-coil 32 generates the sensed-voltage 34 in a range of 0.5V-0.7V. The one or more controller-circuits 28 may control the electrical power 26 to the base-coil 22 based on a location 38 of the vehicle-coil 32 on the vehicle 12. The one or more controller-circuits 28 may control the electrical power 26 applied to the base-coil 22 by controlling a voltage across the base-coil 22, or by controlling a current through the base-coil 22. The one or more controller-circuits 28 may control a rate of the electrical power 26 applied to the base-coil 22 characterized by a linear-function, or characterized by a polynomial-function.
Accordingly, a power transfer system 10 (the system 10), and a method 200 of operating the system 10 are provided. The system 10 is an improvement over prior art power transfer systems because the system 10 increases the sensing-distance 30 between the base-coil 22 and the vehicle-coil 32 without creating a safety hazard of the exposed base-coil 22.
While this invention has been described in terms of the preferred embodiments thereof, it is not intended to be so limited, but rather only to the extent set forth in the claims that follow. “One or more” includes a function being performed by one element, a function being performed by more than one element, e.g., in a distributed fashion, several functions being performed by one element, several functions being performed by several elements, or any combination of the above. It will also be understood that, although the terms first, second, etc. are, in some instances, used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first contact could be termed a second contact, and, similarly, a second contact could be termed a first contact, without departing from the scope of the various described embodiments. The first contact and the second contact are both contacts, but they are not the same contact. The terminology used in the description of the various described embodiments herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description of the various described embodiments and the appended claims, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the term “and/or” as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. It will be further understood that the terms “includes,” “including,” “comprises,” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term “if” is, optionally, construed to mean “when” or “upon” or “in response to determining” or “in response to detecting,” depending on the context. Similarly, the phrase “if it is determined” or “if [a stated condition or event] is detected” is, optionally, construed to mean “upon determining” or “in response to determining” or “upon detecting [the stated condition or event]” or “in response to detecting [the stated condition or event],” depending on the context. Directional terms such as top, bottom, upper, lower, left, right, front, rear, etc. do not denote any particular orientation, but rather these directional terms are used to distinguish one element from another and establish a relationship between the various elements.
