How is the equivalent inductance for inductors connected in series calculated?

When inductors are connected in series, the total or equivalent inductance is calculated by simply adding the individual inductances together. This is because the flux linkage through each inductor adds up when they are connected in series. When you have multiple inductors, the total inductance in the series configuration is the sum of the inductances:

[ L_{\text{eq}} = L_1 + L_2 + ... + L_n ]

In this arrangement, each inductor carries the same current, and their contributions to the total magnetic field strengthen each other. This straightforward addition of inductances is a fundamental property of inductors in series circuit configurations and mirrors the behavior seen in resistances connected in series, enhancing the cumulative effect of the inductive fields.

Consequently, the formulation for equivalent inductance in series is distinctly different from those configurations involving parallel inductors, where the approach to calculate equivalent inductance involves reciprocal relationships.