Percorrer por autor "Albert, W. Malpica"
A mostrar 1 - 4 de 4
Resultados por página
Opções de ordenação
- Fractional order calculus on the estimation of short-circuit impedance of power transformersPublication . Albert, W. Malpica; Silva, J. Fernando; Tenreiro Machado, J. A.; Barros, M. T. CorreiaThis paper reports investigation on the use of fractional order calculus to analytically estimate the inlfuence of skin and proximity effects in the short circuit impedance of power transformers. The aim is to better characterize the medium frequency range behavior of leakage inductances of power transformer models, which include terms to represent the magnetic field diffusion process in the windigns. Comparisons between calculated and measured values are shown and discussed.
- Fractional order dynamics in classical electromagnetic phenomenaPublication . Tenreiro Machado, J. A.; Jesus, Isabel S.; Galhano, Alexandra; Albert, W. Malpica; Silva, Fernando; Tar, József K.The Maxwell equations play a fundamental role in the well established formulation of the electromagnetic theory. These equations lead to the derivation of precise mathematical models useful in many applications in physics and engineering. The Maxwell equations involve only the integer-order calculus and, therefore, it is natural that the resulting classical models adopted in electrical engineering reflect this perspective. Recently, a closer look of some phenomena present in electrical systems, such as motors, transformers and lines, and the motivation towards the development of comprehensive models, seem to point out the requirement for a fractional calculus approach. Bearing these ideas in mind, in this study we shall address the well-known ‘skin effect’ and we reevaluate the results demonstrating its fractional-order dynamics.
- On the Estimation of the Short-Circuit Impedance of Power Transformers Using Fractional Order CalculusPublication . Silva, J. Fernando; Albert, W. Malpica; Machado, J. A. Tenreiro; Barros, M. T. Correia deThis paper reports investigation on the estimation of the short circuit impedance of power transformers, using fractional order calculus to analytically study the influence of the diffusion phenomena in the windings. The aim is to better characterize the medium frequency range behavior of leakage inductances of power transformer models, which include terms to represent the magnetic field diffusion process in the windings. Comparisons between calculated and measured values are shown and discussed.
- Short-Circuit Impedance of Power Transformers: the Fractional Order Calculus ApproachPublication . Silva, J. F. Alves da; Albert, W. Malpica; Machado, J. A. Tenreiro; Barros, M. T. Correia deThis paper reports investigation on the modeling of the short circuit impedance of power transformers, using fractional order calculus, analyzing the influence of the diffusion phenomena in the windings. This aims to better characterize the medium frequency range behavior of leakage inductances of power transformer models, which include terms to represent the magnetic field diffusion in the windings. Calculated and measured values are shown and compared.