Vol. 32

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Active Negative Inductor Based on Magnetic Flux

By Daniel D. Stancil
Progress In Electromagnetics Research C, Vol. 32, 259-269, 2012


An active circuit is described that exhibits the equivalent reactance of a negative inductor. In contrast with previous techniques based on negative impedance converters, the negative inductance is produced by generating an opposing time-varying magnetic flux. The new circuit also enables the inductance to be electronically varied between negative and positive values, can enhance the Q, and defaults to a conventional positive inductor in the event of active component failure. The performance of a prototype with an inductance of -0.344 mH and operating over the frequency range 1-40 kHz is described.


Daniel D. Stancil, "Active Negative Inductor Based on Magnetic Flux," Progress In Electromagnetics Research C, Vol. 32, 259-269, 2012.


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