In really early days of electronic school, the teacher used to say something about not unplug power too quickly at an inductor or capacitor and we were used to slowly turn the voltage generator from a signal generator down to zero. Something about the transients, something about the charge stored...
I'm now interested in working with a power converter, but what was said many years ago still lingers with me but I can't remember exactly what was said at that time.
Can someone please remind me what is the rule when it comes to safely handling inductors and capacitors in a (basic) circuit?
Answer
Thou shall NOT open-circuit a charged inductor.
Thou shall NOT short-circuit a charged capacitor.
If you think about it from their fundamental equations:
\$V = L\dfrac{di}{dt}\$ - a sudden change in current (i.e. forced open circuit) will result in infinite voltage.
\$I = C\dfrac{dv}{dt}\$ - sudden change in voltage (i.e. short circuit) will result in an infinite current.
It's obviously not infinite in practice (due to strays and the ability to change the voltage/current fast enough) BUT it is significant enough to damage electronics...
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