Inductance Conversion Hub

Understanding Inductance & Magnetic Energy Storage

Inductance (denoted as $L$) is the property of an electrical conductor or circuit by which a change in current induces an electromotive force (EMF) opposing that change. It represents electrical inertia, storing potential energy in the surrounding magnetic field: $E = \frac{1}{2} L I^2$.

Faraday's & Lenz's Laws

Self-induced voltage across an inductor is governed by Faraday's Law of Induction with Lenz's sign convention:

$$V_L = -L \frac{di}{dt}$$

For a helical solenoid of $N$ turns, length $\ell$, and core area $A$, inductance is calculated as $L = \frac{\mu N^2 A}{\ell}$. In alternating current circuits, inductive reactance opposes current flow according to $X_L = 2\pi f L$.

Key Units & Conversion Multipliers

• SI Standard: Henry ($\text{H}$). One henry represents the inductance that produces an opposing EMF of one volt when current changes at one ampere per second.
• Sub-Multiples: Millihenry ($\text{mH} = 10^{-3}\text{ H}$), microhenry ($\mu\text{H} = 10^{-6}\text{ H}$), and nanohenry ($\text{nH} = 10^{-9}\text{ H}$).
• CGS Units: Abhenry ($\text{abH} = 10^{-9}\text{ H} = 1\text{ nH}$) and stathenry ($\text{statH} \approx 8.98755 \times 10^{11}\text{ H}$).

Engineering Applications

Essential for designing switch-mode power supply (SMPS) buck/boost chokes, LC radiofrequency resonance filters, wireless inductive charging coils, and mitigating switching transients in motor drives.