Adaptive inductive power supply with communication

#This application incorporates by reference the following references: U.S. Pat. No. 7,212,414 to Baarman, which is entitled “Adaptive Inductive Power Supply” and issued May 1, 2007; U.S. Pat. No. 7,132,918 to Baarman et al., which is entitled “Inductive Coil Assembly” and issued Nov. 7, 2006; and U.S. Pat. No. 7,518,267 to Baarman, which is entitled “Adapter” and issued Apr. 14, 2009. This application also incorporates by reference the full disclosure of the prior applications, including U.S. application Ser. No. 13/078,100 filed Apr. 1, 2011, U.S. Pat. No. 7,953,369 issued May 31, 2011, U.S. Pat. No. 7,522,878 issued Apr. 21, 2009, and U.S. Application No. 60/444,794 filed Feb. 4, 2003.

#This invention relates generally to contactless power supplies, and more specifically to contactless power supplies capable of communicating with any devices receiving power from the contactless power supplies.

#Contactless energy transmission systems (CEETS) transfers electrical energy from one device to another without any mechanical connection. Because there is no mechanical connection, CEETS have many advantages over conventional energy systems. They are generally safer because there is little danger of sparks or electric shocks due to the isolation of the power supply. They also tend to have a longer life since there are no contacts to become worn. Due to these advantages, CEETS have been used in everything from toothbrushes to portable telephones to trains.

#FIG. 1 is a block diagram of an adaptive inductive ballast in accordance with one embodiment of the present invention.

#FIG. 2 is a schematic diagram of the resonance-seeking ballast of the attached patent application marked to show changes to incorporate the adaptive inductive ballast of the present invention.

#FIG. 3 is a flow chart illustrating operation of the adaptive inductive ballast.

#For purposes of disclosure, the present invention is described in connection with a resonance-seeking ballast circuit, and more particularly in connection with the inductive ballast described in U.S. patent application Ser. No. 10/246,155 entitled “Inductively Coupled Ballast Circuit,” which is incorporated in its entirety by reference into this application. The present invention is, however, well suited for use with other inductive ballast circuits.

#A block diagram showing the general construction of an adaptive inductive ballast 10 in accordance with one embodiment of the present invention is shown in FIG. 1. As illustrated, the adaptive inductive ballast 10 generally includes a microprocessor 12 that controls operation of the circuit, a multi-tap primary 14 for generating a magnetic field, a wave shaper and drive subcircuit 16 that generates the signal applied to the primary 14, a current sense subcircuit 18 that monitors the signal applied to the primary 14 and provides corresponding feedback to the microprocessor 12, a capacitance switch 20 for adjusting the capacitance values in the wave shaper and drive subcircuit 16, and an inductance switch 22 for adjusting the inductance of the multi-tap primary 14. The microprocessor is a conventional microprocessor widely available from a variety of suppliers.

#The capacitance switch 20 generally includes two banks of capacitors and a plurality of switches, such as transistors, that are selectively actuatable by the microprocessor 12 to control the values of the two capacitor banks. The capacitors in each bank can be arranged in series or parallel depending on the desired range and distribution of possible capacitance values. The first bank of capacitors replace capacitor 271. Similarly, the second back of capacitors replace capacitor 272 of the pre-existing resonance-seeking ballast shown in the attached patent application. In effect, the capacitance switch 20 makes capacitors 271 and 272 from the pre-existing resonance-seeking ballast into variable capacitors, the values of which are controlled by the microprocessor 12. Alternatively, the described capacitance switch 20 can be replaced by other circuitry capable of providing variable capacitance.