Wireless charging apparatus and terminal using same

Patent metadata

Field	Value
Publication number	US-12500449-B2
Application number	US-202017113328-A
Country	US
Kind code	B2
Filing date	Dec 7, 2020
Priority date	Jun 8, 2018
Publication date	Dec 16, 2025
Grant date	Dec 16, 2025

Abstract

A wireless charging apparatus includes a receive end coil, a switch selection circuit, a plurality of charging circuits, and a receive end controller. An input end of the switch selection circuit is connected to an output end of the receive end coil, and an output end of the switch selection circuit is connected to an input end of each of the charging circuits.

First claim

What is claimed is:

1 . A wireless charging apparatus, located in an electronic device and configured to receive energy from a transmit end coil of a wireless charging transmit end, wherein the wireless charging apparatus comprises:
a receive end coil comprising an output end; a rectifier comprising:
an input end coupled to the output end of the receive end coil;
a first output end; and
a second output end;
a switch selection circuit comprising:
an input end coupled to the first output end of the rectifier; and
an output end;
M charging circuits comprising:
an input end coupled to the output end of the switch selection circuit; and
an output end coupled to a load of the electronic device, wherein a charging power of each of the M charging circuits is different from each other; and
a receive end controller coupled to the M charging circuits, the receive end coil, and the load, wherein the receive end controller is configured to:
obtain a coupling coefficient between the receive end coil and the transmit end coil based on a charging parameter of the receive end coil and the transmit end coil, wherein the coupling coefficient comprises a mutual inductance between the transmit end coil and the receive end coil;
control, based on the coupling coefficient and a battery parameter of a battery of the load, the switch selection circuit to select N charging circuits of the M charging circuits to connect to the receive end coil using the rectifier, wherein the battery parameter comprises a battery level or a battery voltage, wherein M is an integer greater than or equal to 2, and wherein N is an integer greater than or equal to 1 and less than or equal to M; and
control, based on a positive correlation relationship between a first magnitude of the mutual inductance and magnitudes of the charging power of the M charging circuits, the switch selection circuit to select the N charging circuits of the M charging circuits to connect to the receive end coil using the rectifier when the battery parameter is within a preset range,
wherein the preset range of the battery parameter is a range of [X percent (%)−Y %] of a maximum value of the battery level,
wherein X is greater than 2 and less than 5, and
wherein Y is greater than 80 and less than 95.

2 . The wireless charging apparatus of claim 1 , wherein when the battery parameter is within the preset range, the receive end controller is further configured to control, based on a real part of an equivalent impedance, the switch selection circuit to select the N charging circuits with a different power from the M charging circuits to connect to the receive end coil, and wherein a larger real part of the equivalent impedance indicates that a charging circuit with higher charging power is selected to connect to the receive end coil.

3 . The wireless charging apparatus of claim 2 , wherein the receive end controller is further configured to:
obtain a first amplitude of an input voltage of the transmit end coil, a second amplitude of an input current of the transmit end coil, and a phase difference between the input voltage and the input current; and calculate the real part of the equivalent impedance as A cos(θ)/B, wherein θ is the phase difference, wherein A is the first amplitude, and wherein B is the second amplitude.

4 . The wireless charging apparatus of claim 1 , wherein the receive end controller is further configured to:
obtain a first peak value of an output voltage of the receive end coil and a second peak value of an output current of the receive end coil; and calculate the mutual inductance between the transmit end coil and the receive end coil as being equal to the first peak value divided by the second peak value.

5 . The wireless charging apparatus of claim 1 , wherein the switch selection circuit comprises M switching transistors, wherein each of the M switching transistors comprises:
a first end connected to the first output end of the rectifier; and a second end connected to one of the M charging circuits, wherein the M switching transistors are connected to the M charging circuits in a one-to-one correspondence manner.

6 . The wireless charging apparatus of claim 1 , wherein one of the M charging circuits comprises:
a switching diode system comprising:
a first diode;
a second diode coupled to the first diode in series;
a first end coupled to the first output end of the rectifier using the switch selection circuit; and
a second end coupled to the second output end of the rectifier;
an inductor comprising:
a first end coupled to a connection point of the switching diode system, wherein the connection point is a joint between the first diode and the second diode and coupled to the first diode and the second diode, and
a second end;
a first charging capacitor comprising:
a first end coupled to the switch selection circuit; and
a second end coupled to the second output end of the rectifier; and
a second charging capacitor comprising:
a first end coupled to the second output end of the rectifier; and
a second end coupled to the load and the second end of the inductor.

7 . The wireless charging apparatus of claim 1 , wherein one of the M charging circuits comprises:
a first capacitor comprising:
a first end; and
a second end;
a second capacitor comprising:
a first end; and
a second end;
a third capacitor comprising:
a first end; and
a second end;
a first switching diode; a second switching diode; a third switching diode; and a fourth switching diode, wherein the first switching diode, the second switching diode, the third switching diode, and the fourth switching diode are coupled in series with each other in a sequence of the first switching diode, the second switching diode, the third switching diode, and the fourth switching diode and forms a bridge arm, wherein the bridge arm comprises:
a first end coupled to the first output end of the rectifier using the switch selection circuit; and
a second end coupled to the second output end of the rectifier and configured to connect to the load,
wherein the first end of the first capacitor is coupled to the switch selection circuit, wherein the second end of the first capacitor is coupled to the second output end of the rectifier, wherein the first end of the second capacitor is coupled to a first connection point between the first switching diode and the second switching diode, wherein the second end of the second capacitor is coupled to a second connection point between the third switching diode and the fourth switching diode, wherein either the first end of the third capacitor is coupled to a joint between the second switching diode and the third switching diode, or the first end of the third capacitor is coupled to an end of an inductor, and wherein the second end of the third capacitor is coupled to a common connection point between a battery of the load and one end of the load.

8 . The wireless charging apparatus of claim 1 , wherein the coupling coefficient comprises a mutual inductance between the transmit end coil and the receive end coil, wherein, when the battery parameter is within the preset range, the receive end controller is further configured to control, based on a positive correlation relationship between the first magnitude of the mutual inductance and a second magnitude of the charging power of the M charging circuits, the switch selection circuit to select the N of the M charging circuits to connect to the receive end coil using the rectifier wherein the preset range of the battery parameter is a range of [a %−b %] of a rated voltage of the battery, wherein a is greater than 60 and less than 70, and wherein b is greater than 90 and less than 98.

Assignees

• Huawei Tech Co Ltd

Inventors

• Liu Qitang
• Liu Ce
• Shu Weiliang
• Liu Yanding
• Wang Pinghua
• Cao Yong

Classifications

• H02J7/96

  in response to battery voltage · CPC title

• H02J7/933

  the cycle being controlled or terminated in response to electric parameters · CPC title

• H02J7/82

  Control of state of charge [SOC] · CPC title

• H02J7/60

  including safety or protection arrangements · CPC title

• H02J7/61

  against overcharge · CPC title