A fitted formula for calculation of three-section solenoids inductance

An algorithm for precisely calculating the inductance of a three-section solenoid is presented, which is based on summing the layer self-inductances and the mutual inductances. A theoretical model with explicit expressions is firstly developed to calculate the self-inductance of a single layer, and then numerical calculation of the mutual inductance between two layers is introduced. Using the presented computation method, the inductance of a solenoid designed in the experiment is successfully calculated (4.30 mH), which has a difference of less than 1% from the experimental data.