WIRELESS POWER SYSTEM

• US 20170222466A1
• Filed: 09/12/2016
• Published: 08/03/2017
• Est. Priority Date: 07/18/2012
• Status: Active Grant

• Current Assignee: WiPQTUS Inc.
• Original Assignee: WiPQTUS Inc.
• Inventors: Sankar, Ganapathy
• Granted Patent: US 10,122,203 B2
• Time in Patent Office: Days
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 7/0029 with safety or protection devices or circuits
• CPC Class Codes: H02J 7/0047 with monitoring or indicating devices or circuits
• CPC Class Codes: H02J 7/00714 in response to battery charging or discharging current
• CPC Class Codes: H02J 7/007182 in response to battery voltage
• CPC Class Codes: H02J 7/02 for charging batteries from ac mains by converters

Abstract

A higher power wireless power transmitter (HPWPT) including a first, second and third circuit and a transmit coil for wirelessly powering a lower power wireless power receiver (LPWPR) is provided. The first circuit is a switch network. The second circuit is variable impedance network and/or a tuning network. The third circuit is a control logic circuit configured to change the input voltage source or topology of the first circuit, to change the impedance and/or tuning characteristics of the second circuit, to select the transmit coil, vary frequency or duty cycle of the PWM signal or any combination thereof. The change in the input voltage or topology of first circuit or change in impedance or tuning characteristics of second circuit or change in the transmit coil used or the applied constraints on the frequency and duty cycle of the PWM signal constrain the maximum power transmitted by the HPWPT to LPWPR.

Claims

1. A wireless power system comprising:

a wireless power transmitter operatively connected to an input power source, said wireless power transmitter configured to deliver power from said input power source wirelessly to one or more wireless power receivers that are placed within its charging zone

one or more said wireless power receivers configured to receive power wirelessly, said wireless power receivers configured to deliver said received power to their respective load

wherein when said wireless power receiver is placed in said wireless power transmitter'"'"'s charging zone while said wireless power transmitter is already outputting wireless power, said wireless power transmitter and said wireless power receiver both work together to ensure that said wireless power receiver is minimally exposed to unsafe power levels and appropriate actions are taken to prevent damage to said wireless power receiver.

2. The wireless power system of claim 1, wherein on being inserted into the said charging zone of said wireless power transmitter, said wireless power receiver powers up and sends one or more of “

new arrival”

messages, preamble symbols and preamble like messages to said wireless power transmitter.

3. The wireless power system of claim 1, wherein on recognition of newly inserted said wireless power receiver in its said charging zone, said wireless power transmitter throttles back its power output to a safe low level.

4. The wireless power system of claim 1, wherein on recognition of newly inserted said wireless power receiver in its said charging zone, said wireless power transmitter throttles back its power output to a fraction of what it was prior to the said recognition.

5. The wireless power system of claim 1, wherein on recognition of newly inserted said wireless power receiver in its said charging zone, said wireless power transmitter does not change its power output and waits for further messages from said wireless power receiver to decide on changing its said power output.

6. A wireless power system comprising:

a wireless power transmitter operatively connected to an input power source, said wireless power transmitter configured to deliver power from said input power source wirelessly to one or more wireless power receivers that are placed within its charging zone

one or more said wireless power receivers configured to receive power wirelessly, said wireless power receivers configured to deliver said received power to their respective load

wherein when said wireless power receiver is removed from said charging zone of said wireless power transmitter, said wireless power transmitter and said one or more wireless power receivers remaining in the said charging zone, work together to ensure that said wireless power receivers in the said charging zone are minimally exposed to unsafe power levels and appropriate actions are taken to prevent damage to those said wireless power receivers.

7. The wireless power system of claim 6, wherein said wireless power transmitter senses the removal of said wireless power receiver from its said charging zone by tracking the input power that said wireless power transmitter draws from its said input power source in conjunction with messages that it receives from said wireless power receivers that remain in the said charging zone.

8. A wireless power system comprising:

a wireless power transmitter operatively connected to an input power source, said wireless power transmitter configured to deliver power from said input power source wirelessly to one or more wireless power receivers that are placed within its charging zone

one or more said wireless power receivers configured to receive power wirelessly, said wireless power receivers configured to deliver said received power to their respective load

wherein when said wireless power receiver detects surge of input power exceeding safety thresholds, said wireless power receiver performs one or more of;

adjusting its impedance network to reduce the amount of power delivered to rectifier of said wireless power receiver,

adjusting said rectifier configuration to reduce the amount of power delivered to said load,

sending “

unsafe power level”

messages or equivalent symbols to said wireless power transmitter

increasing the amount of filtering capacitance at the output of the said rectifier.