A hybrid finite-element method for the modeling of microcoils

This paper presents an original method for the modeling of microcoils at high frequency dedicated for different applications: radio frequency, nuclear magnetic resonance, nondestructive testing, etc. The aim of the modeling is to determine the elements of an electric equivalent circuit. A magneto-dynamic three-dimensional (3-D) finite-element formulation is used to calculate the resistance and the inductance of the microcoil at high frequency. Using the previous results, an electrostatic 3-D finite-element field analysis is then used to determine the capacitance. The method was tested by using an example of nuclear magnetic resonance microcoil. Numerical results obtained by the proposed method are compared with measurements and analytical results.