Computation of maximal magnetic field value generated by a power substation

Abstract

A procedure for the computation of the maximal value of extremely low frequency (ELF) magnetic fields from a power substation is proposed. The present technique is based on the multiquadric approximation of the magnetic field. The approximation is obtained using discrete field values calculated by the Biot-Savart law, where each energised substation conductor has been divided into a corresponding number of straight segments. The approximation sufficiently handles multidimensional multiextreme functions by interpolating their discrete values accurately. Subsequently, the maximal magnetic field value is evaluated by minimizing the negative multiquadric approximation via a stochastic optimization method -differential evolution. Therefore, the procedure provides the maximal field value assessment on the basis of the limited number of computed discrete values, thus reducing the computational cost.