Method and system for wireless power delivery

• US 10,341,967 B2
• Filed: 06/06/2018
• Issued: 07/02/2019
• Est. Priority Date: 06/06/2017
• Status: Active Grant

• Current Assignee: Reach Power Incorporated
• Original Assignee: Supply, Inc.
• Inventors: Navarro, Gustavo, Ramaswamy, Varun, Davlantes, Christopher Joseph
• Primary Examiner(s): Rego, Dominic E
• Application Number:
  US16/001,725
• Publication Number:
  US 20180352519A1
• Time in Patent Office: 391 Days
• CPC Class Codes: H04W 52/06 TPC algorithms
• CPC Class Codes: H04W 52/223 predicting future states of the transmission
• CPC Class Codes: H04W 52/225 Calculation of statistics, e.g. average, variance
• CPC Class Codes: H04W 52/283 Power depending on the position of the mobile
• CPC Class Codes: H04W 52/34 TPC management, i.e. sharing limited amount of power among users or channels or data types, e.g. cell loading
• CPC Class Codes: H04W 52/367 Power values between minimum and maximum limits, e.g. dynamic range
• CPC Class Codes: H04W 52/50 at the moment of starting communication in a multiple access environment

Abstract

A system for wireless power delivery including one or more transmitters and receivers. A method for wireless power delivery, preferably including: determining transmitter-receiver proximity; determining transmission parameter values, preferably including determining initial parameter values, evaluating candidate transmission parameter values, performing one or more local optimum searches, and/or performing one or more global optimum searches; and transmitting power based on the transmission parameter values.

Claims

1. A method for wireless power transmission, comprising:

at a transmitter comprising an adaptive antenna array, determining that a receiver is in transmission range of the transmitter;

in response to determining that the receiver is in transmission range, performing a stochastic global search, based on an objective function, over a transmission parameter space associated with the adaptive antenna array;

based on the stochastic global search, determining an optimized parameter value set, the optimized parameter value set comprising a respective value for each parameter of the transmission parameter space; and

at the transmitter, wirelessly transmitting power to the receiver by transmitting based on the optimized parameter value set;

wherein performing the stochastic global search comprises, for each parameter value set of a series of parameter value sets within the transmission parameter space;

determining a respective value, associated with the respective parameter value set, of the objective function;

based on the respective parameter value set and the respective value, determining a respective subsequent parameter value set; and

in response to determining the respective subsequent parameter value set, if a search convergence criterion has not been met, adding the respective subsequent parameter value set to the series;

wherein determining the respective value of the objective function comprises;

at the transmitter, throughout a respective time interval, transmitting power based on the respective parameter value set;

at the receiver, during the respective time interval, receiving power transmitted by the transmitter;

determining a respective amount of power received at the receiver during the respective time interval; and

determining the respective value based on the respective amount of power.

2. The method of claim 1, further comprising, before performing the stochastic global search:

in response to determining that the receiver is in transmission range, performing a local search, based on the objective function, over the transmission parameter space;

based on the local search, determining a locally-optimized parameter value set, the locally-optimized parameter value set comprising a respective value for each parameter of the transmission parameter space; and

determining that the locally-optimized parameter value set does not exceed a threshold objective function value, wherein the stochastic global search is performed in response to determining that the locally-optimized parameter value set does not exceed the threshold objective function value.

3. The method of claim 1, wherein:

performing the stochastic global search further comprises determining a local approximation of objective function values in a region of the transmission parameter space comprising a first parameter value set of the series; and

for the first parameter value set, the respective subsequent parameter value set is determined based further on the local approximation.

4. The method of claim 3, wherein determining the local approximation comprises:

performing a local search, based on the objective function, over the region; and

based on the local search, determining a local optimum value associated with the objective function;

wherein the local approximation of objective function values in the region is substantially constant over the region and is substantially equal to the local optimum value.

5. The method of claim 1, further comprising:

while the receiver is in transmission range of the transmitter, at the transmitter, determining that a second receiver is in transmission range of the transmitter; and

while wirelessly transmitting power to the receiver, wirelessly transmitting power to the second receiver by transmitting based on the optimized parameter value set;

wherein;

determining the respective value of the objective function further comprises;

at the second receiver, during the respective time interval, receiving power transmitted by the transmitter; and

determining a respective second amount of power received at the second receiver during the respective time interval; and

determining the respective value is based further on the respective second amount of power.

6. The method of claim 5, wherein:

determining the respective value of the objective function further comprises;

at the receiver, communicating a first dataset indicative of the respective amount of power to the transmitter; and

at the second receiver, communicating a second dataset indicative of the respective second amount of power to the transmitter; and

determining the respective value is performed by the transmitter based on the first and second datasets.

7. The method of claim 6, further comprising:

for each parameter value set of the series, at the transmitter, in response to receiving the first dataset, storing information associated with the first dataset;

while wirelessly transmitting power to the receiver, determining that the second receiver is not in transmission range of the transmitter;

in response to determining that the second receiver is not in transmission range of the transmitter, at the transmitter, determining a modified parameter value set based on the information; and

in response to determining the modified parameter value set, at the transmitter, wirelessly transmitting power to the receiver by transmitting based on the modified parameter value set.

8. The method of claim 5, wherein the objective function is equal to w₁f₁+P₁(|f₁−

f₁*|)+w₂f₂+P₂(|f₂−

f₂*|), wherein w₁ is a receiver weighting associated with the receiver, f₁ is the amount of power, f₁* is a maximum amount of power expected to be deliverable to the receiver, P₁ is a penalty function associated with the receiver, w₂ is a second receiver weighting associated with the second receiver, f₂ is the second amount of power, f₂* is a second maximum amount of power expected to be deliverable to the second receiver, and P₂ is a second penalty function associated with the second receiver.

9. The method of claim 1, further comprising:

while transmitting based on the optimized parameter value set, determining that power received at the receiver has reduced;

in response to determining that power reception at the receiver has reduced, performing a local search, based on the objective function, over the transmission parameter space; and

based on the local search, determining a locally-optimized parameter value set, the locally-optimized parameter value set comprising a respective value for each parameter of the transmission parameter space.

10. The method of claim 9, further comprising:

determining that the locally-optimized parameter value set does not exceed a threshold objective function value; and

in response to determining that the locally-optimized parameter value set does not exceed the threshold objective function value, performing a second stochastic global search, based on the objective function, over the transmission parameter space.

11. The method of claim 1, wherein, for each of the series of parameter value sets, determining the respective subsequent parameter value set is performed based further on a particle swarm optimization algorithm.

12. The method of claim 1, wherein the transmission parameter space comprises, for each active antenna of a plurality of active antennas of the adaptive antenna array, a respective phase parameter.

13. A method for wireless power transmission, comprising:

at a transmitter comprising an adaptive antenna array, determining that a receiver is in transmission range of the transmitter;

in response to determining that the receiver is in transmission range, performing a local search, based on an objective function, over a transmission parameter space associated with the adaptive antenna array;

based on the local search, determining an optimized parameter value set, the optimized parameter value set comprising a respective value for each parameter of the transmission parameter space;

determining that the optimized parameter value set exceeds a threshold objective function value; and

in response to determining that the optimized parameter value set exceeds the threshold objective function value, at the transmitter, wirelessly transmitting power to the receiver by transmitting based on the optimized parameter value set;

wherein performing the local search comprises, for each parameter value set of a series of parameter value sets within the transmission parameter space;

determining a respective value, associated with the respective parameter value set, of the objective function;

based on the respective parameter value set and the respective value, determining a subsequent parameter value set; and

in response to determining the subsequent parameter value set, if a search convergence criterion has not been met, adding the subsequent parameter value set to the series;

wherein determining the respective value of the objective function comprises;

at the transmitter, throughout a respective time interval, transmitting power based on the respective parameter value set;

at the receiver, during the respective time interval, receiving power transmitted by the transmitter;

determining a respective amount of power received at the receiver during the respective time interval; and

determining the respective value based on the respective amount of power.

14. The method of claim 13, wherein, for each of the series of parameter value sets, determining the respective subsequent parameter value set is performed based further on a gradient-free search algorithm.

15. The method of claim 14, wherein the gradient-free search algorithm comprises at least one of:

a Nelder-Mead algorithm and an adaptive meshing algorithm.

16. The method of claim 13, further comprising:

while the receiver is in transmission range of the transmitter, at the transmitter, determining that a second receiver is in transmission range of the transmitter; and

while wirelessly transmitting power to the receiver, wirelessly transmitting power to the second receiver by transmitting based on the optimized parameter value set;

wherein;

determining the respective value of the objective function further comprises;

at the second receiver, during the respective time interval, receiving power transmitted by the transmitter; and

determining a respective second amount of power received at the second receiver during the respective time interval; and

determining the respective value is based further on the respective second amount of power.

17. The method of claim 16, wherein:

determining the respective value of the objective function further comprises;

at the receiver, communicating a first dataset indicative of the respective amount of power to the transmitter; and

at the second receiver, communicating a second dataset indicative of the respective second amount of power to the transmitter; and

determining the respective value is performed by the transmitter based on the first and second datasets.

18. The method of claim 16, wherein the objective function is equal to w₁f₁+P₁(|f₁−

f₁*|)+w₂f₂+P₂(|f₂−

f₂*|), wherein w₁ is a receiver weighting associated with the receiver, f₁ is the amount of power, f₁* is a maximum amount of power expected to be deliverable to the receiver, P₁ is a penalty function associated with the receiver, w₂ is a second receiver weighting associated with the second receiver, f₂ is the second amount of power, f₂* is a second maximum amount of power expected to be deliverable to the second receiver, and P₂ is a second penalty function associated with the second receiver.

19. The method of claim 13, wherein the transmission parameter space comprises, for each active antenna of a plurality of active antennas of the adaptive antenna array, a respective phase parameter.

20. The method of claim 19, wherein the transmission parameter space further comprises, for each active antenna of the plurality, a respective amplitude parameter.

21. The method of claim 19, wherein the transmission parameter space further comprises, for each of a plurality of passive antennas of the adaptive antenna array, a respective electrical component coupling parameter.

22. The method of claim 13, wherein the receiver comprises a supergaining structure.