**Article details**

**Title: **Self and Mutual Inductivities Computation Using Symbolic Method

**Author(s): ***Florin Enache* *Gheorghe Gavrilă*

**Abstract: ** In the designing and realization of electromagnetic devices, an important problem is represented by the calculation of self and mutual inductivities. There are many methods which can be used for this, as follows: the direct method, the calculation by means of reluctance (when the coils are placed on the magnetic circuits), utilizing Neumann’s formula and the calculation on basis of the energetic definition of inductivity. Even in the case of linear magnetic media, the problem is not simple, because it is necessary that the magnetic flux density be calculated as accurately as possible, in a lot of points from space. An adequate method for this purpose is the utilization of symbolic methods with the MAPLE simulator. After some theoretical considerations, a few applications relating to self and mutual inductivities calculation are presented in the paper. The results obtained are discussed, pointing out the advantages of symbolic methods: fast calculation, but without the loss of the physical meaning of the problem.

**Keywords: **self-inductivity, mutual inductivity, Neumann’s formula, symbolic methods

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