Author(s)

N. Kovač, D. Poljak, S. Kraljević & B. Jajac

Abstract

A procedure for a computation of the maximal value of extremely low frequency (ELF) electric field from a power substation is proposed. The present technique is based on a multiquadric approximation of the electric field. The approximation is obtained using discrete field values calculated by the Source Element Method (SEM) representing a variant of Indirect Boundary Element Method (IBEM). The approximation sufficiently handles multidimensional multiextreme functions by interpolating their discrete values accurately. Subsequently, the maximal electric field value is evaluated by minimizing the negative multiquadric approximation via the stochastic optimization method – differential evolution. Therefore, the procedure provides the maximal field value assessment on the basis of a limited number of computed discrete values, thus reducing the computational effort. 1 Introduction A computation of the maximal value of extremely low frequency (ELF) electric field from a power substation has been of great interest in last decades. The reason for this is the increasing public concern regarding the possible health risk for human exposure to ELF electric field and magnetic flux density. It is to be noticed that the present piece of work has been focused only toward the technical aspects of electric field assessment. The ELF electric field from substations has been determined via the computations or/and measurements in [1–6], presenting a number of three-dimensional as well as contour plots. Nevertheless, they provided a useful description of the field characteristics, no technique incorporating certain optimization method for assessing the maximal electric field value has been applied in these papers. The spatial electric field function

Keywords