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Old 06-05-2009, 04:24 PM
Peter Lindemann Peter Lindemann is offline
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Join Date: Apr 2007
Location: Liberty Lake, Washington
Posts: 1,191
Excellent

Quote:
Originally Posted by Michael John Nunnerley View Post
Here is the circuit, which I think will need more work with experimenting. How it works is the heating coil and C1 is an LC circuit, the pick up coil controls the mosfet at the frequency of the oscillation of the LC circuit, VR is for the set point of the mosfet. Between VR and the positive rail should be a resistor of about 10K, which is not shown, to protect the mosfet. When the mosfet is off, C1 supplies the current, when on the battery supplies the current. There is no switching of polarity on the heating element coil, no diodes are needed.

THIS IS EXPERIMENTAL

Mike
Michael,

Yes, your circuit idea should work. There is also the simplest version of the circuit, which is just the Inductive Heating Element in a tank circuit with a corresponding Capacitor, driven by a variable AC sine-wave Power Supply at the natural frequency of the resonant tank. Also, if the components were large enough, the system could be tuned to run at 60hz. Then, there would be no local electronic components at all and the Heater Coil would simply run as an "idling" inductor with a local power factor correcting capacitor.

Peter
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