Wireless power transmission device and foreign object detection coil thereof for detecting metallic foreign object
First Claim
1. A wireless power transmission device, comprising:
- an alternating current (AC) to direct current (DC) converter having an input terminal to receive an AC power and convert the AC power into a DC power;
a DC to AC converter having;
an input terminal electrically connected to an output terminal of the AC to DC converter to convert the DC power into an AC output power; and
multiple compensation capacitors electrically connected to a transmission antenna to transmit the AC output power in the form of electromagnetic waves through the transmission antenna;
multiple foreign object detection (FOD) coils for detecting metallic foreign object mounted on an insulating substrate to sense the electromagnetic waves and generate multiple sensed signals, each FOD coil having three coil units connected in series to and spaced apart from one another, wherein a radiation pattern of the transmission antenna overlaps a sensing range of the FOD coils;
a reference voltage generation circuit having an input terminal electrically connected to the multiple compensation capacitors of the DC to AC converter to receive terminal voltages of any one of the multiple compensation capacitors and generate a reference voltage signal according to the terminal voltages of the compensation capacitor;
multiple feedback detection circuits electrically connected to the respective FOD coils, each feedback detection circuit receiving the sensed signal of a corresponding FOD coil; and
a controller electrically connected to the reference voltage generation circuit and the multiple feedback detection circuits to receive the reference voltage signal and the sensed signals corresponding to the multiple FOD coils and determine if any metallic foreign object enter a range of electromagnetic waves generated by the transmission antenna according to the reference voltage signal and the sensed signals.
1 Assignment
0 Petitions
Accused Products
Abstract
A wireless power transmission device radiates electromagnetic waves through a transmission antenna and generates multiple sensed signals by using multiple foreign object detection (FOD) coils for detecting metallic foreign object to sense the electromagnetic waves. Each FOD coil has three coil units connected in series to and spaced apart from one another. The radiation pattern of the transmission antenna overlaps a sensing range of the FOD coils. A controller of the wireless power transmission device determines if any metallic foreign object enters the radiation range of the transmission antenna according to a reference voltage signal and sensed signals of the cells, and stops the generation of electromagnetic waves when determining entry of metallic foreign object into the radiation range to avoid the metallic foreign object to be heated by the electromagnetic waves.
-
Citations
10 Claims
-
1. A wireless power transmission device, comprising:
-
an alternating current (AC) to direct current (DC) converter having an input terminal to receive an AC power and convert the AC power into a DC power; a DC to AC converter having; an input terminal electrically connected to an output terminal of the AC to DC converter to convert the DC power into an AC output power; and multiple compensation capacitors electrically connected to a transmission antenna to transmit the AC output power in the form of electromagnetic waves through the transmission antenna; multiple foreign object detection (FOD) coils for detecting metallic foreign object mounted on an insulating substrate to sense the electromagnetic waves and generate multiple sensed signals, each FOD coil having three coil units connected in series to and spaced apart from one another, wherein a radiation pattern of the transmission antenna overlaps a sensing range of the FOD coils; a reference voltage generation circuit having an input terminal electrically connected to the multiple compensation capacitors of the DC to AC converter to receive terminal voltages of any one of the multiple compensation capacitors and generate a reference voltage signal according to the terminal voltages of the compensation capacitor; multiple feedback detection circuits electrically connected to the respective FOD coils, each feedback detection circuit receiving the sensed signal of a corresponding FOD coil; and a controller electrically connected to the reference voltage generation circuit and the multiple feedback detection circuits to receive the reference voltage signal and the sensed signals corresponding to the multiple FOD coils and determine if any metallic foreign object enter a range of electromagnetic waves generated by the transmission antenna according to the reference voltage signal and the sensed signals. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A foreign object detection (FOD) coil for detecting metallic foreign object formed with a single conductor on a planar insulating substrate, and comprising:
-
three coil units directly connected in series to and spaced apart from one another, each of the three coil units having a starting terminal and an ending terminal, wherein the ending terminal of a first one of the three coil units is directly connected to the ending terminal of a second one of the three coil units, and the starting terminal of a third one of the three coil units is directly connected to the starting terminal of the second one of the three coil units, wherein the starting terminal is the input terminal of each of the three coil units and the ending terminal is the output terminal of each of the three coil units; and wherein the first one of the three coil units is wound in a first direction such that the current flows in the first direction, the second one of the three coil units is wound in in an opposite direction such that the current flows in the opposite direction from the first direction, and the third one of the three coil units is wound in a first direction such that the current flows in the first direction; and two terminals, one of the two terminals being the starting terminal of the first one of the three coil units and the other terminal being the ending terminal of the third one of the three coil units wherein each of the three coil units has a center segment, a first segment, a second segment, a third segment, a fourth segment, a fifth segment and a sixth segment mounted on a surface of the insulating substrate; wherein the center segment is U-shaped and has two ends, the first segment, the second segment and the third segment are mounted on the surface of the insulating substrate and are sequentially arranged outwards on a side of the center segment;
the third segment is electrically connected to one end of the fifth segment, the other end of the fifth segment is electrically connected to one end of the first segment through a connection segment. - View Dependent Claims (8, 9, 10)
-
Specification