SUMMARY A highly accurate and robust Marquardt least squares method, which simultaneously solves a set of nonlinear equations, is employed to analyse the accuracy of the Heidler function parameters recommended by IEC 62350–1 Ed. 2. In addition, Heidler function parameters for reproduction of various frequently used standardized waveshapes are provided. The possibility of using the Marquardt least squares method for fitting Heidler function to actual measured data is explored. Copyright © 2011 John Wiley & Sons, Ltd.

In this paper, a 3D quasi-static numerical algorithm for computation of the magnetic field produced by power lines is presented. These power lines can be overhead power line phase conductors and shield wires or buried cable line phase conductors. The basis of the presented algorithm is the application of Biot-Savart law and the thin-wire approximation of cylindrical conductors. The catenary form of the power line conductors is approximated by a set of straight cylindrical segments. By summing up contributions of all conductor segments, magnetic field distribution is computed. On the basis of the presented theory, a FORTRAN program PFEMF for computation of the magnetic flux density distribution was developed. For each conductor catenary, it is necessary to define only global coordinates of the beginning and ending points and also the value of the longitudinal phase conductor current. Global coordinates of beginning and ending points of each catenary segment are generated automatically in PFEMF. Numerical results obtained by program PFEMF are compared with results obtained by simple 2D model and results obtained using software package CDEGS.

In this paper, a 3D quasistatic numerical algorithm for computation of the electric field produced by overhead power lines is presented. The real catenary form of the overhead power line phase conductors and shield wires is taken into account with an arbitrary number of straight thin-wire cylindrical segments of active and passive conductors. In order to obtain more precise results of the charge density distribution, segmentation is conducted for each overhead power line span separately. Moreover, the presence of the towers which distort the electric field and significantly reduce its magnitude is taken into account. Therefore, the towers of overhead power lines are approximated using thin-wire cylindrical segments of passive conductors with electric potential equal to zero. From self and mutual coefficients of these components, system of linear equations for computation of the charge density distribution was obtained. In the numerical example, electric field intensity distribution in the vicinity of towers and under the midspan of overhead power lines is shown. In order to verify the accuracy of the presented model, the obtained results are compared with similar published examples and results available in the literature.

In this paper a 2D numerical algorithm is presented for the computation of electric and magnetic fields of power lines. The numerical algorithm for the electric field intensity computation takes into account a short power line and approximates the conductor charge density by a constant. The numerical algorithm for magnetic flux density computation is based on the application of the Biot-Savart law. The computed results are compared to measurements taken underneath a 400 kV power line. The computed results and measurements prove to be in good agreements keeping in mind that the sag of the power line section is approximated with a horizontal straight line. Both the computed results as well as measurements confirm the fact that the electric and magnetic fields of high voltage power lines are well within the prescribed limits.