Inductive power supply with duty cycle control
First Claim
1. An inductive power supply for providing power wirelessly to a remote device, said inductive power supply comprising:
- a primary circuit for generating a signal at an operating frequency, said primary circuit being capable of adjusting a duty cycle of said signal to allow variation in an amount of power transferred to the remote device at said operating frequency;
a tank circuit in electrical communication with said primary circuit, wherein said primary circuit applies said signal to said tank circuit to transfer an amount of power to said remote device;
said inductive power supply configured to receive feedback from said remote device;
said primary circuit being configured to control said operating frequency of said signal in response to said feedback to optimize power transfer efficiency between said inductive power supply and said remote device; and
said primary circuit being configured to control said duty cycle of said signal in response to said feedback to control said amount of power transferred to said remote device at said operating frequency.
2 Assignments
0 Petitions
Accused Products
Abstract
An inductive power supply that maintains resonance and adjusts duty cycle based on feedback from a secondary circuit. A controller, driver circuit and switching circuit cooperate to generate an AC signal at a selected operating frequency and duty cycle. The AC signal is applied to the tank circuit to create an inductive field for powering the secondary. The secondary communicates feedback about the received power back to the primary controller. The power transfer efficiency may be optimized by maintaining the operating frequency substantially at resonance, and the amount of power transferred may be controlled by adjusting the duty cycle.
-
Citations
35 Claims
-
1. An inductive power supply for providing power wirelessly to a remote device, said inductive power supply comprising:
-
a primary circuit for generating a signal at an operating frequency, said primary circuit being capable of adjusting a duty cycle of said signal to allow variation in an amount of power transferred to the remote device at said operating frequency; a tank circuit in electrical communication with said primary circuit, wherein said primary circuit applies said signal to said tank circuit to transfer an amount of power to said remote device; said inductive power supply configured to receive feedback from said remote device; said primary circuit being configured to control said operating frequency of said signal in response to said feedback to optimize power transfer efficiency between said inductive power supply and said remote device; and said primary circuit being configured to control said duty cycle of said signal in response to said feedback to control said amount of power transferred to said remote device at said operating frequency. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 31, 32)
-
-
9. An inductive power supply system comprising:
-
an inductive power supply including; a primary circuit for generating a signal at an operating frequency and for adjusting a duty cycle of said signal to control an amount of power transferred at said operating frequency; and a tank circuit in electrical communication with said primary circuit, wherein said primary circuit applies said signal to said tank circuit to transfer an amount of power to said remote device; said inductive power supply configured to receive feedback from said remote device; a remote device separable from said inductive power supply for receiving power from said inductive power supply, said remote device including; a secondary energized by said inductive field, a load in electrical communication with said secondary, a sensor in electrical communication with said secondary, a secondary controller in electrical communication with said sensor, and a communication device in electrical communication with said secondary controller for sending feedback to said inductive power supply; wherein, in response to said feedback, said primary circuit controls said operating frequency of said signal to optimize power transfer efficiency between said inductive power supply and said remote device; and wherein, in response to said feedback, said primary circuit controls said duty cycle of said signal to control said amount of power transferred to said remote device at said operating frequency. - View Dependent Claims (10, 11, 12, 13, 14, 15, 16, 33)
-
-
17. A method for transferring power from an inductive power supply to a remote device, said method comprising:
-
setting an initial operating frequency of a signal in the inductive power supply; setting an initial duty cycle of the signal to set an initial power level in the inductive power supply; applying the signal to a tank circuit for transferring an amount of power from the inductive power supply to a remote device; receiving, in the inductive power supply, feedback from the remote device; adjusting, in response to the feedback, the operating frequency of the signal to optimize power transfer efficiency between the inductive power supply and the remote device; adjusting, in response to the feedback, the duty cycle of the signal to control the amount of power transferred to the remote device. - View Dependent Claims (18, 19, 20, 21, 22)
-
-
23. An inductive power supply for a remote device comprising:
-
a tank circuit; a primary circuit in electrical communication with said tank circuit, said primary circuit configured to apply a signal to said tank circuit; and a receiver configured to receive communications from the remote device, said receiver in electrical communication with said primary circuit, said primary circuit configured to selectively adjust an operating frequency of said signal as a function of said communications to optimize power transfer efficiency from said tank circuit to the remote device, said primary circuit configured to selectively adjust a duty cycle of said signal as a function of said communications to control an amount of power transferred to the remote device at said operating frequency, whereby said inductive power supply maintains power transfer efficiency through operating frequency adjustments and while maintaining appropriate power level though duty cycle adjustments. - View Dependent Claims (24, 25)
-
-
26. A method for wirelessly supplying power to a remote device, comprising the steps of:
-
placing a remote device in sufficient proximity to an inductive power supply to establish an inductive coupling between the remote device and the inductive power supply; in the inductive power supply, applying a signal to a tank circuit at a plurality of different operating frequencies to wirelessly transfer power to the remote device; in the remote device, taking separate measurements of a characteristic of the power wirelessly received from the inductive power supply for each of said different operating frequencies; determining an initial operating frequency based on the separate measurements; and in the inductive power supply, applying a signal to the tank circuit at the initial operating frequency receiving, in the inductive power supply, communication from the remote device; adjusting, in response to the communication, the operating frequency of the signal to optimize power transfer efficiency between the inductive power supply and the remote device; and adjusting, in response to the communication, the duty cycle of the signal to control the amount of power transferred to the remote device. - View Dependent Claims (27, 28, 29, 30, 34, 35)
-
Specification