4.6: Energy Stored in Inductors
An inductor is ingeniously crafted to accumulate energy within its magnetic field. This field is a direct result of the current that meanders through its coiled structure. When this current maintains a steady state, there is no detectable voltage across the inductor, prompting it to mimic the behavior of a short circuit when faced with direct current.
In terms of gauging the energy stored within an inductor, it is equivalent to the integral of the power delivered at every individual moment, all accumulated over a specific duration of time. Mathematically, energy stored in an inductor is expressed as
Where w is the energy stored in the inductor, L is the inductance and i is the current passing through the inductor.
Ideal inductors have a noteworthy characteristic - they do not dissipate energy. This trait allows the energy stored within them to be harnessed at a later point in time. However, this ideal scenario is slightly marred when dealing with non-ideal inductors.
Non-ideal inductors exhibit a phenomenon known as winding resistance. This resistance stems from the coils of the conductor and presents itself in series with the inductance. While this winding resistance has the potential to contribute to energy dissipation, it is typically so minuscule that it can be conveniently overlooked in practical applications.
Additionally, non-ideal inductors also display winding capacitance. This is due to the capacitive coupling that occurs between the conducting coils. However, this winding capacitance is usually so minute that it can be disregarded, except when dealing with high frequencies.
