Frequency-dependent skin-effect formulation for resistance and internal inductance of a solid cylindrical conductor

A new simple formulation is presented to calculate the skin-effect resistance and internal inductance of a solid cylindrical conductor. The formulation is obtained from the exact solution of Maxwell's wave equation of an electrical field in the direction of propagation. The Fourier transform method is used to obtain the frequency-domain solution. Results are presented in graphical form showing the conductor resistance and internal inductance as a function of frequency.151321221

Analysis Of The Electromagnetic Field Transient Inside A Shielded Structure

This work presents an analysis of the behavior of the electromagnetic field inside a shielded structure (shielded enclosure), when it is submitted to a transitory of electric current. The shielded structure is used in systems of electrical protection by annulling the electromagnetic field in its interior. A closed structure, made up of a considerable number of interconnected cables, it can become a good approach for a Faraday cage. Based on this approach, simulations of the transitory of electric current in the structure were made. Connected to this was a current source at one of its borders, and grounding the plane of its base. Through the transitory of obtained current, the electromagnetic field, in time domain, applying an expression adequately developed for this end was simulated. Analysis of results for different configurations were made.1239242Thomas, D., Christopoulos, C., Pereira, E., Calculation of radiated electromagnetic fields from cables using time-domain simulation (1994) IEEE Transaction on Electromagnetic Compatibility, 36. , AugustRubinstein, M., Uman, M.A., Methods for calculating the electromagnetic fields from a know source distribution: Application to lightning (1989) IEEE Transaction on Electromagnetic Compatibility, 31. , MayPaul, C.R., Bush, D.R., Radiated fields of interconnected cables (1984) IEEE International Conference on Electromagnetic Compatibility, pp. 259-264. , SeptemberCaixeta, G.P., Pissolato Filho, J., Electromagnetic fields generated by lighting on protection structures of telecommunication centers (1997) IEEE International Symposium on Electromagnetic Compatibility, , AugustRamo, J.R.W.S., Duzer, T.V., (1984) Fields and Waves in Communication Electronics, , John Wiley & SonsCaixeta, G.P., Pissolato Filho, J., Calculation of electromagnetic fields from arbitrary conductors configurations in time-domain simulations (1998) International Symposium on Electromagnetic Compatibility, EMC'RomaS8, , SeptemberChristopoulos, C., Propagation of surges above the corona threshold on a line with a lossy earth return (1985) COMPEL, 4 (2), pp. 91-10

A procedure to estimate parameters of a line segment taking into account its representation through π circuits: Theoretical development

The objective of this paper is to show an alternative methodology to estimate per unit length parameters of a line segment of a transmission line. With this methodology the line segment parameters can be obtained starting from the phase currents and voltages in receiving and sending end of the line segment. If the line segment is represented as being one or more π circuits whose frequency dependent parameters are considered lumped, its impedance and admittance can be easily expressed as functions of the currents and voltages at the sending and receiving end. Because we are supposing that voltages and currents at the sending and receiving end of the line segment (in frequency domain) are known, it is possible to obtains its impedance and admittance and consequently its per unit length longitudinal and transversal parameters. The procedure will be applied to estimate the longitudinal and transversal parameters of a small segment of a single-phase line that is already built. © 2006 IEEE

Quasi-modes Three-phase Transmission Line Model - Transformation Matrix Equations

This paper describes the quasi-modes three-phase transmission line model, a new model to represent three-phase transmission lines in transient studies, with proper representation of the frequency dependence of longitudinal parameters. A unique transformation matrix - the Clarke matrix - is used for the entire frequency range. As this matrix is a real one. it can be modeled through ideal transformers. The circuit equations, which lead to the matrix modeling, are presented. This line model can be implemented in any digital program with R, L, C and transformer components. © 2001 Published by Elsevier Science Ltd.234323331Clarke, E., (1950) Circuit analysis of AC power systems, 1. , New York: Wiley(1987) Alternative Transients Program Rule Book, , JulyTavares, M.C., Pissolato, J., Portela, C.M., Quasi-modes multiphase transmission line model (1999) Electric Power Systems Research International Journal, 49 (3), pp. 159-167Tavares, M.C., Pissolato, J., Portela, C.M., New multiphase mode domain transmission line model (1999) International Journal of Electrical Power & Energy Systems, 21 (8), pp. 585-601Semlyen, A., Stability analysis and stabilizing procedure for a frequency dependent line model (1984) IEEE Transactions on Power Apparatus and Systems, 103 (12), pp. 3579-3586Marti, J.R., Accurate modeling of frequency-dependent transmission lines in electromagnetic transients simulations (1982) IEEE Transactions on Power Apparatus and Systems, 101 (1), pp. 147-157Brandão Faria, J.A., Briceño Mendez, J., On the modal analysis of asymmetrical three-phase transmission lines using standard transformation matrices (1997) IEEE Transactions on Power Delivery, 12 (4), pp. 1760-1765Portela, C.M., Tavares, M.C., Six phase transmission line - Propagation characteristics and new three-phase representation (1993) IEEE Transactions on Power Delivery, 8 (3), pp. 1470-1483Tavares, M.C., Pissolato, J., Portela, C.M., New mode-domain representation of transmission line - Clarke transformation analysis (1998) Proc. 1998 IEEE International Symposium on Circuits and Systems, 3, pp. 497-500. , Monterey, California, US

Mode domain multiphase transmission line model - Use in transient studies

This paper presents a new model to represent multiphase transmission lines in transient studies, including the frequency dependence of longitudinal parameters. The model uses the exact modes, for ideally transposed lines, and 'quasi-modes' for non-transposed lines, For the latter it is necessary to have a vertical symmetry plane, The frequency dependence is represented with synthetic circuits, with one pi-circuit for each mode. The transformation matrix used for the entire frequency range is the Clarke's one and as it is a real matrix it is modeled through ideal transformers. The model is described for three-phase lines and double three-phase lines, An application of the methodology is presented for a 440 kV single three-phase transmission line where it is made mode analysis, statistical energization and frequency scan analysis, The simulations are performed in EMTP with the proposed model and with a frequency dependent EMTP line model, the Semlyen one, supposing the line transposed anti non-transposed.1441533154

New Multiphase Mode Domain Transmission Line Model

This article presents a new model to represent transmission lines including the frequency dependence of longitudinal parameters. The model uses exact modes, for ideally transposed lines, and "quasi-modes" for non-transposed lines. The line is represented through a cascade of π-circuits, with one π-circuit for each mode. The transformation matrix used is real and it is modeled with ideal transformers. The model is described for three-phase lines, dc lines, double three-phase lines and six-phase lines. An ATP-EMTP implementation of a 440 kV three-phase transmission line is performed to illustrate the model and a comparison with two frequency dependent ATP line models are made, the Semlyen and JMarti ones. © 1999 Elsevier Science Ltd. All rights reserved.218585601(1987) Alternative Transients Program Rule Book, , JulySemlyen, A., Dabuleanu, A., Fast and accurate switching transient calculations on transmission lines with ground return using recursive convolution (1975) IEEE Trans PAS, 94 (2), pp. 561-571Marti, J.R., Accurate modeling of frequency-dependent transmission lines in electromagnetic transients simulations (1982) IEEE Trans PAS, 101 (1), pp. 147-157Clarke, E., (1950) Circuit Analysis of AC Power Systems, 1. , New York: WileyBrandã, O., Faria, J.A., Bricefio Mendez, J., On the modal analysis of asymmetrical three phase transmission lines using standard transformation matrices (1997) IEEE Winter Meeting, , Paper 97WMIEEE-PESTavares, M.C., Pissolato, J., Portela, C.M., New mode-domain representation of transmission line-Clarke transformation analysis (1998) 1998 IEEE International Symposium on Circuits and Systems (ISCAS' 98), pp. III497-500. , Monterey, California, USATavares, M.C., Pissolato, J., Portela, C.M., Quasi-modes multiphase transmission line model (1999) Electric Power Systems Research, 49, pp. 159-167Portela, C.M., Tavares, M.C., Six phase transmission line-propogation characteristics and new three phase representation (1993) IEEE Trans Power Delivery, 8 (3), pp. 1470-1483Tavares, M.C., Pissolato, J., Portela, C.M., Mode domain multiphase transmission line-use in transient studies (1998) IEEE Summer Meeting, , Paper PE-430-PWRD-0-04-1988, San Diego, USA, JulyBrandão Faria, J.A., Briceño Mendez, J., Modal analysis of untransposed bilateral three phase lines-a perturbation approach (1996) IEEE Summer Meeting, , Paper 96SM438-2PWRD, Denver, USA, JulyPortela, C.M., Tavares, M.C., Azeved, R.M., New Line Representation for Transient Studies - Application to a Six Phase Transmission LineSemlyen, A., Wilson, R.L., Gelopulos, D., Paper discussion of component transformations - Eigenvalue analysis succintly defines their relationships (1982) IEEE Trans PAS, 101, pp. 405-40

Some Considerations About A New Procedure To Derive Transmission Line Parameters Concerning Three-phase Lines

The paper shows an alternative methodology to calculate transmission line parameters per unit length and to apply it in a three-phase line with a vertical symmetry plane. This procedure is derived from a general procedure where the modal transformation matrix of the line is required. In this paper, the unknown modal transformation matrix requested by general procedure is substituted by Clarke's matrix. With the substitution that is shown in the paper, the transmission line parameters can be obtained starting from impedances measured in one terminal of the line. First, the article shows the classical methodology to calculate frequency dependent transmission line parameters by using Carson and Pollaczeck's equations for representing the ground effect and Bessel's functions to represent the skin effect. After that, a new procedure is shown to calculate frequency dependent transmission line parameters directly from currents and voltages of an existing line. Then, this procedure is applied in a non-transposed three-phase transmission line whose parameters have been previously calculated by using the classical methodology. Finally, the results obtained by using the new procedure and by using the classical methodology are compared. The article shows simulation results for typical frequency spectra of switching transients (10 Hz to 10 kHz). Results have shown that procedure has © 2006 IEEE.Hofmann, L., Series expansions for line series impedances considering different specific resistances, magnetic permeabilities, and dielectric permittivities of conductors, air, and ground (2003) IEEE Trans. on Power Delivery, 18 (2), pp. 564-570. , AprPortela, C., Tavares, M.C., Modeling, simulation and optimization of transmission lines. Applicability and limitations of some used procedures (2002) IEEE PES Transmission and Distribution, , São Paulo, BrazilSemlyen, A., Some frequency domain aspects of wave propagation on nonuniform lines (2003) IEEE Trans, on Power Delivery, 18 (1), pp. 315-322. , JanS. Kurokawa, J. Pissolato, M. C. Tavares, C. M. Portela and A. J. Prado, A New procedure to derive transmission line parameters: Applications and restrictions, IEEE Trans. on Power Delivery, TPWRD-00566-2004 (article accepted and waiting to be published)Akke, M., Biro, T., Measurements of the frequency-dependent impedance of a thin wire with ground return IEEE Trans, on Power Delivery (Digital object identifier 101109/TPWRD.2004.834320)Marti, J.R., Accurate modeling of frequency-dependent transmission line in electromagnetic transient simulations (1982) IEEE Trans. Power App. and Systems, PAS-101 (NO1), pp. 147-155. , JanDommel, H.W., (1986) EMTP theory book, , VancouverWedephol, L.M., Nguyen, H.V., Irwin, G.D., Frequency-dependent transformation matrices for untransposed transmission lines using Newton-Raphson method (1996) IEEE Trans. Power Systems, 11 (NO3), pp. 1538-1546. , AugBrandão Faria, J.A., Briceno Mendez, J.H., Modal analysis of untransposed bilateral three-phase lines - A perturbation approach (1997) IEEE Trans. Power Delivery, 12 (NO1), pp. 497-504. , JanBudner, A., Introduction of frequency-dependent line parameters into an electromagnetic transients programs (1970) IEEE Trans. Power App. and Systems, PAS-89 (NO1), pp. 88-97. , JanBrandão Faria, J.A., Briceno, J.H., On the modal analysis of asymmetrical three-phase lines using standard transformation matrices (1997) IEEE Trans. Power Delivery, 12 (4), pp. 1760-1765. , OctTavares, M.C., Pissolato, J., Portela, C.M., Quasi-modes multiphase transmission line model (1999) Electric Power Systems Research, (49), pp. 159-167Tavares, M.C., Pissolato, J., Portela, C.M., Mode domain multiphase transmission line model - Use in transient studies (1999) IEEE Trans. Power App. and Systems, 14 (4), pp. 1533-1544. , OctMarti, L., Low-order approximation of transmission line parameters for frequency-dependent models (1983) IEEE Trans. Power App. and Systems, PAS-102 (11), pp. 3582-3589. , No