Modelling of nonlinear rail impedance in AC traction power systems

Author

Hill, R. John ; Carpenter, David C.

Author_Institution

Sch. of Electr. Eng., Bath Univ., UK

Volume

6

Issue

4

fYear

1991

fDate

10/1/1991 12:00:00 AM

Firstpage

1755

Lastpage

1761

Abstract

Nonlinearity in the internal self-impedance of railroad rail can give rise to power frequency harmonics in traction systems. Limiting case analytical models of rail impedance, based on linear complex permeability and complete saturation, are compared with measurements for currents to 800 A and frequencies to 10 kHz. The results show that for accurate representation an effective permeability of the material must be defined by prior modeling of the eddy current flux distribution within the rail iron. The usual assumption of rail, internal self-impedance invariance with current is shown to be unrealistic

Keywords

eddy currents; electric impedance; harmonics; power supplies to apparatus; traction; 10 kHz; 800 Å; AC traction power systems; eddy current flux distribution; internal self-impedance; linear complex permeability; nonlinear rail impedance; power frequency harmonics; railroad rail; saturation; Analytical models; Current measurement; Frequency; Impedance; Permeability; Power system analysis computing; Power system harmonics; Power system measurements; Power system modeling; Rails;

fLanguage

English

Journal_Title

Power Delivery, IEEE Transactions on

Publisher

ieee

ISSN

0885-8977

Type

jour

DOI

10.1109/61.97717

Filename

97717