System and method for inductively charging a battery
First Claim
Patent Images
1. An inductive charging system comprising:
- a primary circuit including a power source, a controller electrically coupled to said power source and a primary coil electrically coupled to said controller, wherein said controller applies power with a frequency to said primary coil from said power source;
a secondary circuit including a secondary coil inductively coupled to said primary coil, a feedback circuit electrically coupled to said secondary coil and a battery electrically coupled to and chargeable by power from said secondary coil;
wherein said feedback circuit includes an over-voltage detector and an over-current detector arranged to control a switch, wherein in response to an over-voltage condition or an over-current condition said feedback circuit communicates feedback to said primary circuit via said inductive coupling by actuating said switch to direct current from said secondary coil through an impedance element to vary a reflected impedance of said secondary circuit;
wherein said controller controls a characteristic of said power applied to said primary to correct said over-voltage condition or said over-current condition at least partially in response to said feedback.
2 Assignments
0 Petitions
Accused Products
Abstract
An inductive charging system for recharging a battery. The system includes a charger circuit and a secondary circuit. The secondary circuit includes a feedback mechanism to provide feedback to the charger circuit through the inductive coupling of the primary coil and the secondary coil. The charger circuit includes a frequency control mechanism for controlling the frequency of the power applied to the primary coil at least partly in response to the feedback from the feedback mechanism.
135 Citations
24 Claims
-
1. An inductive charging system comprising:
-
a primary circuit including a power source, a controller electrically coupled to said power source and a primary coil electrically coupled to said controller, wherein said controller applies power with a frequency to said primary coil from said power source; a secondary circuit including a secondary coil inductively coupled to said primary coil, a feedback circuit electrically coupled to said secondary coil and a battery electrically coupled to and chargeable by power from said secondary coil; wherein said feedback circuit includes an over-voltage detector and an over-current detector arranged to control a switch, wherein in response to an over-voltage condition or an over-current condition said feedback circuit communicates feedback to said primary circuit via said inductive coupling by actuating said switch to direct current from said secondary coil through an impedance element to vary a reflected impedance of said secondary circuit; wherein said controller controls a characteristic of said power applied to said primary to correct said over-voltage condition or said over-current condition at least partially in response to said feedback. - View Dependent Claims (2, 3, 4)
-
-
5. An inductive charging system comprising:
-
a primary circuit including a power source, a controller electrically coupled to said power source and a primary coil electrically coupled to said controller, wherein said controller applies power with a frequency to said primary coil from said power source; a secondary circuit including a secondary coil inductively coupled to said primary coil, a feedback circuit electrically coupled to said secondary coil and a battery electrically coupled to and chargeable by power from said secondary coil; wherein said feedback circuit communicates feedback to said primary circuit via said inductive coupling by actuating said switch to direct current from said secondary coil through an impedance element to vary a reflected impedance of said secondary circuit; wherein said primary circuit includes a peak detector that provides a detection signal to said controller in response to detecting an over-voltage condition or an over-current condition; and wherein said controller controls a characteristic of said power applied to said primary to correct said over-voltage condition or said over-current condition at least partially in response to said feedback from said feedback circuit. - View Dependent Claims (6, 7, 8, 9, 10, 11, 12, 13)
-
-
14. A method for operating an inductive charging system according to a charging profile, said inductive charging system having a charger circuit with a primary coil and a secondary circuit with a secondary coil and a battery, the method comprising the steps of:
-
defining an over-voltage condition and over-current condition according to the charging profile; applying power to the primary coil at a frequency; receiving power in the secondary coil; charging the battery with the received power; generating a feedback signal by actuating a switch to direct current from said secondary coil through an impedance element to vary a reflected impedance the secondary circuit in response to the over-voltage or the over-current condition being met; evaluating the feedback signal from the secondary circuit through the primary coil and secondary coil inductive coupling; and adjusting the frequency of the power applied to the primary coil to correct said over-voltage condition or said over-current condition as a function of the feedback from the secondary circuit. - View Dependent Claims (15, 16, 17, 18, 19, 20, 21)
-
-
22. A portable electronic device with a secondary circuit having a reflected impedance for receiving power from an inductive charger having a primary coil, said portable electronic device comprising:
-
a secondary coil; a battery electrically coupled to and chargeable by power from said secondary coil; and a feedback circuit electrically coupled to said secondary coil wherein said feedback circuit varies the reflected impedance of said secondary circuit to generate a feedback signal in said secondary coil to said primary coil in response to an over-voltage or over-current condition by actuating a switch to direct current from said secondary coil through an impedance element, wherein said feedback signal causes a characteristic of power applied to said primary coil to vary to correct said over-voltage condition or said over-current condition. - View Dependent Claims (23, 24)
-
Specification