Inductor reset

Another term often used in power, one that tells us that we have managed to return to the same inductor current (and energy) that we started off with, is called inductor reset. Reset occurs at the very moment when the equality AIoff = AIon is established. Of course, we could also have a non-repetitive (or single-shot ) event, where the current starts at zero and then returns to zero — and that too would be inductor reset. ... 

The corollary is that in a repetitive switching scenario (steady state), an inductor must be able to reset every cycle. Reversing the argument — any circuit configuration that makes inductor reset an impossibility, is not a viable switching topology. 

Yes, if we wait long enough the inductor current will finally ramp down to zero (inductor reset ). But if we don t wait, and turn the switch back ON again, the current will again start to ramp up (staircasing), as shown in Figure 1-10. 

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