Wireless charging system with receiver locating circuitry and foreign object detection
First Claim
1. A wireless power transmitting device configured to transmit wireless power signals to a wireless power receiving coil in a wireless power receiving device, comprising:
- an array of wireless power transmitting coils;
inverter circuitry coupled to the array of wireless power transmitting coils;
impulse response measurement circuitry coupled to the array of wireless power transmitting coils; and
control circuitry configured to;
store valid sets of coil inductances for the array, wherein each valid set of coil inductances corresponds to inductance values for the wireless power transmitting coils in the array that occur when the wireless power receiving device is present on the charging surface in the absence of foreign objects;
measure inductance values for at least some of the wireless power transmitting coils with the impulse response measurement circuitry; and
compare the measured inductance values to the valid sets of coil inductances associated with the array of wireless power transmitting coils to determine whether the wireless power receiving device is present on the array in the absence of foreign objects.
1 Assignment
0 Petitions
Accused Products
Abstract
A wireless power transmission system has a wireless power receiving device that is located on a charging surface of a wireless power transmitting device. The wireless power receiving device has a wireless power receiving coil and the wireless power transmitting device has a wireless power transmitting coil array. Control circuitry in the transmitting device uses inverter circuitry to supply alternating-current signals to coils in the coil array, thereby transmitting wireless power signals. Impulse response measurement circuitry coupled to the coil array is used to make impulse response measurements while the control circuitry uses the inverter circuitry to apply impulse signals to each of the coils. The control circuitry analyzes output from the impulse response measurement circuitry to measure inductances associated with the coils in the coil array.
16 Citations
19 Claims
-
1. A wireless power transmitting device configured to transmit wireless power signals to a wireless power receiving coil in a wireless power receiving device, comprising:
-
an array of wireless power transmitting coils; inverter circuitry coupled to the array of wireless power transmitting coils; impulse response measurement circuitry coupled to the array of wireless power transmitting coils; and control circuitry configured to; store valid sets of coil inductances for the array, wherein each valid set of coil inductances corresponds to inductance values for the wireless power transmitting coils in the array that occur when the wireless power receiving device is present on the charging surface in the absence of foreign objects; measure inductance values for at least some of the wireless power transmitting coils with the impulse response measurement circuitry; and compare the measured inductance values to the valid sets of coil inductances associated with the array of wireless power transmitting coils to determine whether the wireless power receiving device is present on the array in the absence of foreign objects. - View Dependent Claims (2, 3, 4, 5)
-
-
6. A wireless power transmitting device configured to transmit wireless power signals to a wireless power receiving device, comprising:
-
an array of wireless power transmitting coils; inverter circuitry coupled to the array of wireless power transmitting coils; inductance measurement circuitry coupled to the array of wireless power transmitting coils; and control circuitry configured to; measure inductance values for at least some of the wireless power transmitting coils by applying impulses to the wireless power transmitting coils with the inverter circuitry and measuring corresponding impulse responses with the inductance measurement circuitry; and determine whether foreign objects are present on the array of wireless power transmitting coils at least partly by comparing the measured inductance values to coil inductance values associated with presence of the wireless power receiving device on the array of wireless power transmitting coils in absence of any foreign objects. - View Dependent Claims (7, 8, 9, 10, 11, 12)
-
-
13. A wireless power transmitting device configured to transmit wireless power signals to a wireless power receiving device, comprising:
-
an array of wireless power transmitting coils, wherein the wireless power transmitting coils have a nominal inductance value in absence of foreign objects and the wireless power receiving device; wireless power transmitter circuitry coupled to the array of wireless power transmitting coils; inductance measurement circuitry coupled to the array of wireless power transmitting coils; and control circuitry configured to; measure inductance values for at least some of the wireless power transmitting coils with the inductance measurement circuitry; and compare the measured inductance values to sets of coil inductance values for the array of wireless power transmitting coils that are associated with presence of the wireless power receiving device on the array of wireless power transmitting coils in absence of foreign objects, wherein each one of the coil inductance values in each set is different than the nominal inductance value. - View Dependent Claims (14, 15, 16, 17, 18, 19)
-
Specification