Wireless power system

• US 10,122,203 B2
• Filed: 09/12/2016
• Issued: 11/06/2018
• Est. Priority Date: 07/18/2012
• Status: Active Grant

• Current Assignee: WiPQTUS Inc.
• Original Assignee: WiPQTUS Inc.
• Inventors: Sankar, Ganapathy
• Primary Examiner(s): Shin, Jeffrey
• Application Number:
  US15/263,311
• Publication Number:
  US 20170222466A1
• Time in Patent Office: 785 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, the wireless power transmitter configured to deliver power from the input power source wirelessly to one or more wireless power receivers that are placed within a charging zone of the wireless power transmitter,

wherein when a wireless power receivers is placed within the wireless power transmitter'"'"'s charging zone, the wireless power receiver is configured to receive power wirelessly to deliver the received power to its load;

wherein when a new wireless power receiver is placed into the wireless power transmitter'"'"'s charging zone while the wireless power transmitter is already outputting wireless power, the wireless power transmitter senses the new wireless power receiver and constrains its wireless power output to ensure that new wireless power receiver is minimally exposed to unsafe power levels.

2. The wireless power system of claim 1, wherein said wireless power transmitter senses the insertion of new said wireless power receiver into its said charging zone via one or more of “

new arrival”

messages, preamble symbols and preamble like messages from said inserted wireless power receiver.

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 3, wherein said wireless power transmitter following throttling back its power output to a safe low level, said wireless power transmitter increasing the power output back up gradually ensuring that said inserted wireless power receiver has had sufficient time to adjust its internal circuitry to compensate and protect itself under higher power levels.

6. The wireless power system of claim 4, wherein said wireless power transmitter following throttling back its power output its power output to a fraction of what it was prior, said wireless power transmitter increasing the power output back up gradually ensuring that said inserted wireless power receiver has had sufficient time to adjust its internal circuitry to compensate and protect itself under higher power levels.

7. A wireless power system comprising:

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

wherein when a wireless power receiver is placed within the wireless power transmitter'"'"'s charging zone, the wireless power receiver is configured to receive power wirelessly to deliver the received power to its load;

wherein when one of the wireless power receivers currently in the charging zone and receiving power wirelessly is removed from the charging zone of the wireless power transmitter, the wireless power transmitter senses the removal of the wireless power receiver and constrains its power output to ensure that the wireless power receivers that still remain in the charging zone are minimally exposed to unsafe power levels.

8. The wireless power system of claim 7, 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.

9. A wireless power system comprising:

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

wherein when a wireless power receiver is placed within the wireless power transmitter'"'"'s charging zone, the wireless power receiver is configured to receive power wirelessly to deliver the received power to its load;

wherein while receiving power wirelessly if the wireless power receiver detects a surge of received power exceeding safety thresholds, the wireless power receiver performs one or more of;

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

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

increasing the amount of filtering capacitance at the output of the rectifier,

to ensure that its internal circuitry is protected from damage without specific assistance from the wireless power transmitter.