Capacitance Calculation Using Eem

Sometimes physical systems can be so complex that analytical solutions for potentials or electric fields strength of those problems are difficult or even impossible to be found. Fortunately, with the application of the computer, it is now possible to use simple numerical approximation methods to solve more complex problems in a matter of a few minutes. For determination an unknown capacitance can be used different numerical methods. In this article, the Equivalent Electrodes Method (EEM) [9] is used for calculation of system capacitance. A sphere and thin ring form this system. In paper [5], the authors called that system “Saturn” capacitor. In this article, the capacitance of this system, when the capacitor ring has finite or negligible thickness is calculated. Also, the ring cross-section can have different shapes. The capacitance calculation has been done for several ring cross-section shapes. The Equivalent Electrodes Method, Point-matching Method and Image theorem are used for calculation. The convergence of the results will be shown in the tables, and the capacitance values for different values of parameters will be shown graphically. Also, the obtained results for capacitance for different ring cross-section shapes will be shown in the tables. In last few years there has been developed a large number of software packages for solving problems in Electromagnetics. They make calculations easier and it is also a good way to confirm the results obtained by some analytical or numerical method. In this article, the obtained EEM results will be compared with FEMM software [10] results.