文档介绍：ELECTRIC LANGUAGE
Text Inductor
I have studied inductor have properties of inductance (which oppose a change in current) and resistance in the wire from which the inductor is wound (which opposes current flow).The amount of inductance, L (measured in henrys), relates to the physical properties of the coil, including the length, cross-sectional area, number of turns, and type that develops for any given rate of current change through the coil.
Also, you know when a dc voltage is first applied to a circuit with an inductor present; current does not instantly rise to the value dictated by the dc resistance of the circuit divided by the applied voltage. This delay is due to the inductor’s opposing any current change. It takes five L/R time constants for plete change from one current level (even if it is zero amperes) to a new current level. Under opposite conditions (I. e.) if the dc source is removed from the inductor circuit ) current will not abruptly decrease to zero, since the inductor opposes the current change and the collapsing field induces an e m f in the coil to attempt to prevent the current from changing. When the time constant is very small during the decay sequence, the field quickly collapses, inducing a very high voltage in the coil, therefore, make sure that current is not abruptly interrupted through the inductor in general dc circuits. When it must be a