Factor C anf takes into account the influence of parts of the rod, which protrude from the coil.when there is a radial gap between the core and the coil. Factor μ fe considers the case when the winding is not tight adjoined to the core, i.e.The ratio of the magnetic reluctance of the two paths of the magnetic circuit of the air-core coil is marked in the basic formula as x and it is computed in the 5th step of the algorithm. If the magnetic reluctance of the inner part of the magnetic circuit is higher than the outer part, then the using of ferrite reduces the reluctance and has the effect to increase the inductance. They differ in the density of magnetic field lines and magnetic reluctance. We can assume that the air core coil has a magnetic circuit consisting of two parts.The dimensions in meters, see signs on the picture:Ī bit of theory explaining the algorithm: Where ε 0 = 8,8542*10 -12 F/m is the electric constant, μ is the initial magnetic permeability of the rod material. ,where L f / L air is the ratio of the inductance of the coil with the ferrite to the inductance of the same coil without ferrite and the factors x, k & μ fe are calculated according to the following algorithm: The basic formula looks like this: μ e = L f / L air = (1 + x) / (1 / k + x / μ fe ) In other words, we need to determine how the inductance of the air-core coil will be increased if inside it to insert a ferrite rod. the position of the coil relative to the center of the rod.Ĭalculation of the coil inductance on a ferrite rod is based on the determination of the relative effective permeability of the rod.the mutual ratio of sizes of the coil and rod.ferrite rod magnetic permeability and its sizes.Unlike a toroidal inductor on a ferrite ring, the magnetic flux of the coil on the ferrite rod is not fitting completely within the ferrite and each magnetic field line goes through the ferrite core and through the air, so the calculation of such coil is more complex. Ferrite core inductor at radio frequency.Multilayer air core inductor on a rectangular form.Self-capacitance of single-layer inductor.Features of calculation of power supply chokes.How to calculate single layer LC-circuit coil in Coil64?.

Ferrite rod inductor calculator