4.7 : Series and Parallel Inductors

In electrical circuits, integrating inductors into the toolkit of passive elements requires navigating the intricacies of series and parallel combinations involving these components. Practical circuits often feature configurations of multiple inductors, and understanding how to determine their equivalent inductance is vital.

For a series connection of N inductors, each carrying the same current, applying Kirchhoff's voltage law unveils a crucial relationship. Substituting the expression for inductor voltages leads to an insightful conclusion: the equivalent inductance of this series arrangement is the simple summation of the individual inductances. This phenomenon mirrors how resistors combine in series, emphasizing a fundamental similarity between these passive elements.

In a parallel connection of inductors, each bears an identical voltage; Kirchhoff's current law can be applied. This leads to a significant revelation: the reciprocal of the equivalent inductance is equal to the sum of the reciprocals of the individual inductances. This parallel combination rule mirrors the behavior of resistors in parallel, illustrating a harmonious approach to dealing with different passive elements.

In practice, circuits often feature a blend of series and parallel inductors. When confronted with such scenarios, the equivalent inductance of the parallel inductors is calculated and added to the series inductance to obtain the overall equivalent inductance of the circuit.