Finite Element Analysis of Magnetic Field Distribution for 500-kV Power Transmission Systems

This paper proposes a set of mathematical models presenting magnetic fields caused by operations of an extra high voltage (EHV) transmission line under normal loading and short-circuit conditions. The mathematical models are expressed in second-order partial differential equations derived by analyzing magnetic field distribution around a 500-kV power transmission line. Finite element methods (FEM) for solving wave equations have been exploited. The modification for complex magnetic field analysis and time-harmonic simulation are also utilized. The computer simulation based on the use of the FEM has been developed in MATLAB programming environment. The problem of study is intentionally two-dimensional due to the property of long line field distribution. To verify its use, i) single-circuit and ii) double-circuit, 500-kV power transmission lines have been employed for test. From all test cases, the calculation line of 1.0 m above the ground level is set to investigate the magnetic fields acting on a human in comparative with ICNIRP standard. Moreover, visualization of magnetic fields caused by fault currents flowing through EHV transmission lines is included.