System and method for wireless vehicle battery charging
Presented herein is a system and method for wireless power transmission (WPT) charging of a battery of a stationary electric vehicle (EV). The system comprises a plurality of autonomous mobile platforms adapted to charge the battery, wherein: the autonomous mobile platforms are configured to fit under the EV; and one or more autonomous mobile platforms are assigned in succession by the central control system to fully supply the charging requirements of the EV. Also presented is a method for maximizing inductive WPT charging of a battery of a stationary EV.
1 . A mobile platform for wirelessly charging an in-vehicle rechargeable battery by a charge receiver in an electric vehicle (EV) that is located in a stationary location on a surface, the mobile platform comprising:
a charge transmitter for generating a field for a wireless charging by a wireless energy transfer to the charge receiver in the field;
a movement sensor that provides an output in response to a movement of the platform;
multiple wheels that are independently-controlled for moving the platform on the surface;
a drive chain for powering the multiple wheels for propelling and steering the platform on the surface;
a wireless transmitter for transmitting data to, and a wireless receiver for receiving data from, a wireless network;
a memory storing software, and a processor coupled to the memory for executing the software;
a rechargeable electric power storage for electrically powering the charge transmitter, the movement sensor, the memory, the drive chain, the wireless transmitter, the wireless receiver, and the processor; and
a housing sized and shaped to fit under the EV,
wherein the rechargeable electric power storage, the charge transmitter, the movement sensor, the memory, the processor, the drive chain, the wireless transmitter, the wireless receiver, or any combination thereof, are attached to, or mounted in, the housing,
wherein the processor is coupled to the movement sensor and to the drive chain for controlling the propelling and steering to automatically travel to the EV location in response to a receiving of a message over the wireless network that is indicative of the EV stationary location,
wherein the platform is further configured for localizing the housing under the EV using a feedback-based closed control loop of the wireless energy transfer of the in-vehicle rechargeable battery by the charge transmitter, and
wherein the platform is further configured for vertically moving the charge transmitter upwards or downwards for optimizing of the wireless energy transfer between the platform and the EV.
2 . The platform according to claim 1 , wherein the field is a magnetic field, and wherein the wireless energy transfer uses, comprises, or is based on, a near-field inductive energy transfer that uses magnetic field resonant coupling.
3 . The platform according to claim 2 , for use with a first coil in the charge receiver, wherein the charge transmitter comprises a second coil that is configured for inductive energy transfer with the first coil when the housing is under the EV.
4 . The platform according to claim 3 , further comprising a compensating network connected to the second coil, wherein the second coil is circular, rectangular, Haxagonal, or Double D (DD) shaped.
5 . The platform according to claim 2 , wherein the wireless energy transfer uses a frequency that is in a 20 KHz-100 KHz frequency band, or wherein the wireless energy transfer uses a frequency that is in a 81.39 KHz-90 KHz frequency band.
6 . The platform according to claim 1 , for use with a first plate in the charge receiver, wherein the field is an electric field, wherein the wireless energy transfer comprises, or is based on, a near-field capacitive energy transfer that uses an electric field coupling, and wherein the charge transmitter comprises a second plate that is configured for capacitive energy transfer with the first plate when the housing is under the EV.
7 . The platform according to claim 1 , wherein the wireless energy transfer is according to, based on, compliant with, or compatible with, a Wireless Power Transmission (WPT) standard that is according to, based on, compliant with, or compatible with, an SAE International SAE Technical Information Report (TIR) J2954, SAE J2954, SAE J2954/1, SAE J2954/2, or SAE J2846/7 standard.
8 . The platform according to claim 1 , wherein the localizing uses, is based on, or uses, an orientation or rotation of the EV that is received from the wireless network by the wireless receiver.
9 . The platform according to claim 1 , wherein the rechargeable electric power storage comprises one or more rechargeable batteries, and wherein each one of the multiple wheels comprises a respective omni or Mechanum wheel.
10 . The platform according to claim 1 , wherein the charge transmitter, the movement sensor, the memory, the drive chain, the wireless transmitter, the wireless receiver, the rechargeable electric power storage, the processor, or any combination thereof, are non-removably embedded in the housing.
11 . The platform according to claim 10 , further comprising a camera configured for detecting an attempt to forcefully gain access or, or to remove an element from, the housing, and wherein the platform is further configured to provide an alarm or visual output in response to the detecting.
12 . The platform according to claim 1 , wherein the EV comprises an electric vehicle, a hybrid vehicle, a private sedan vehicle, a Recreational Vehicle (RV), a minivan, a pickup truck, a delivery van, an ambulance, a commercial truck, or any combination thereof.
13 . The platform according to claim 1 , further configured to record activities of the platform and to store the recorded activities in the memory.
14 . The platform according to claim 1 , further comprising a location sensor for providing an estimated location of the platform in a coordinate system to the processor, wherein the platform is further configured to automatically travel to the EV location using, or based on, the estimated location.
15 . The platform according to claim 14 , for use with multiple Radio-Frequency (RF) signals transmitted by multiple sources, wherein the location is estimated by receiving of the RF signals from the multiple sources via one or more antennas, and processing or comparing the received RF signals.
16 . The platform according to claim 15 , wherein the multiple sources comprise satellites that are part of Global Navigation Satellite System (GNSS).
17 . The platform according to claim 16 , wherein the GNSS comprises a Global Positioning System (GPS) and the location sensor comprises a GPS antenna coupled to a GPS receiver for receiving and analyzing GPS signals, or wherein the GNSS comprises a GLObal NAvigation Satellite System (GLONASS) and the location sensor comprises a GLONASS antenna coupled to a GLONASS receiver for receiving and analyzing GLONASS signals.
18 . The platform according to claim 1 , wherein the memory further stores a map, and wherein the platform automatically travels to the EV location using, or based on, the stored map.
19 . The platform according to claim 18 , wherein the platform automatically travels to the EV using, or based on, a dead reckoning.
20 . The platform according to claim 14 , for use in an area that comprises multiple markers detectable by the location sensor, wherein the platform automatically travels to the EV location using, or based on, the multiple markers.
21 . The platform according to claim 20 , wherein the markers comprise optical markers, Wireless Personal Area Network (WPAN) markers, Bluetooth markers, Radio Frequency Identification (RFID) based markers, or any combination thereof.
22 . The platform according to claim 1 , further comprising an object detector coupled to the processor for detecting an obstacle when the platform automatically travels to the EV location.
23 . The platform according to claim 22 , further configured to provide a warning, to stop the travelling, to change a travel route to the EV location, or any combination thereof, in response to the detecting of the obstacle.
24 . The platform according to claim 1 , further comprising a navigation software stored in the memory for controlling the platform along a route to the EV or from the EV, and wherein the platform is further configured for travelling to or from the EV along an available energy efficient route.
25 . The platform according to claim 1 , wherein the movement sensor comprises an inertial sensor for sensing a movement of the housing, and wherein the platform is configured to automatically travel to the EV location using, or based on, the sensed movement.
26 . The platform according to claim 25 , wherein the inertial sensor comprises, is based on, or is part of, an accelerometer or a gyroscope.
27 . The platform according to claim 1 , wherein the movement sensor comprises a non-inertial sensor for sensing an environmental condition.
28 . The platform according to claim 27 , wherein the non-inertial sensor comprises, is based on, or is part of, a barometer, an altimeter, a magnetometer, a light sensor, a camera, an additional wireless receiver, or any combination thereof.
29 . The platform according to claim 27 , wherein the non-inertial sensor comprises, is based on, or is part of, an additional wireless receiver that is based on, or is part of, a Radio Frequency Identification (RFID) receiver, a Bluetooth receiver, a Global Positioning System (GPS) receiver, or a GLObal NAvigation Satellite System (GLONASS) receiver.
30 . The platform according to claim 1 , wherein the wireless network comprises, uses, or is compatible with, a Wireless Local Area Network (WLAN), the wireless transmitter comprises a WLAN transmitter, and the wireless receiver comprises a WLAN receiver, or wherein the wireless network comprises, uses, or is compatible with, a Wireless Personal Area Network (WPAN), the wireless transmitter comprises a WPAN transmitter, and the wireless receiver comprises a WPAN receiver.
31 . The platform according to claim 30 , wherein the wireless network comprises, uses, or is compatible with, a WPAN that comprises, is based on, or is compatible with, Bluetooth.
32 . The platform according to claim 1 , further comprising a first sensor that provides an output value that is responsive to an amount of energy transferred over the wireless energy transfer from the charge transmitter to the charge receiver.
33 . The platform according to claim 32 , wherein the localizing comprises travelling to a position and orientation using the output value as an input to the feedback-based closed control loop for optimal energy transfer.
34 . The platform according to claim 32 , for use with a threshold, wherein the platform moves in response to the output value being above or below the threshold.
35 . The platform according to claim 32 , wherein the output value is responsive to a measured or detected magnetic field feature or characteristic.
36 . The platform according to claim 35 , wherein the output value is responsive to a magnetic field strength, to a magnetic field direction, or any combination thereof.
37 . The platform according to claim 35 , wherein the output value is responsive to a magnetic field rate of change, to a magnetic field frequency, or any combination thereof.
38 . The platform according to claim 32 , wherein the output value is responsive to a measured or detected voltage or current supplied to the charge transmitter, to a phase difference between the measured voltage and current supplied to the charge transmitter, or any combination thereof, and wherein the first sensor comprises a Hall-effect sensor.
39 . The platform according to claim 1 , further comprising a first sensor that provides an output value that is proportional to, or indicative of, a real power delivered by the charge transmitter to the charge receiver.
40 . The platform according to claim 39 , for use with an optimal location on the surface of the housing relative to the EV stationary location that provides a maximum value of the real power delivered by the charge transmitter to the charge receiver, wherein the localizing comprises arriving to the optimal location using the output value as an input to the feedback-based control loop.
41 . The platform according to claim 40 , wherein the optimal location is a global maximum or a local maximum location, and wherein the platform is configured to perform multiple iterations until arriving to the optimal location.
42 . The platform according to claim 41 , wherein the platform is configured to perform a ‘Gradient Ascent’ or ‘Gradient Descent’ scheme for arriving to the optimal location.
43 . The platform according to claim 41 , wherein each iteration comprises a movement increment in a first direction, followed by a movement increment in a second direction that is perpendicular to the first direction.
44 . The platform according to claim 41 , wherein each iteration further comprises a rotation of the platform.
45 . The platform according to claim 1 , for use with a control device that communicates with the platform over the wireless network, wherein the platform is further configured to transmit, to the control device over the wireless network using the wireless transmitter, a movement sensor output, and to receive, from the control device over the wireless network using the wireless receiver, a command that is responsive to the movement sensor output.
46 . The platform according to claim 45 , wherein the automatically travel to the EV location is based on, or in response to, the received command.
47 . The platform according to claim 1 , for use with a charging station that is powered by an electricity grid, wherein the platform is further configured to automatically travel to the charging station for charging the rechargeable electric power storage from the electricity grid by the charging station.
48 . The platform according to claim 47 , further for use with an electric socket in the charging station that comprises slots for providing an electric power, wherein the platform further comprises mating prongs for insertion to the electric socket for receiving the electric power therefrom, or for use with an electric socket in the charging station that comprises prongs for providing an electric power, wherein the platform further comprises mating slots for insertion to the electric socket for receiving the electric power therefrom.
49 . The platform according to claim 47 , wherein the charging from the charging station comprises wirelessly charging.
50 . The platform according to claim 47 , wherein the charging from the charging station ends in response to sensing that the rechargeable electric power storage is fully charged, or wherein the charging from the charging station ends in response to receiving by the wireless receiver of a message from the wireless network.