Evaluation of current levels in the presence of harmonics for proper coordination using transmittances

Author

Field, Thomas E.

Author_Institution

Nashville Electr. Service, TN, USA

fYear

1997

fDate

9-11 Mar 1997

Firstpage

234

Lastpage

238

Abstract

This paper presents two of the problems which can occur when both RMS and fundamental responsive protection devices are used in a radial distribution system which has both source voltage distortion and nonlinear loads. The transmittance equations used to calculate the current contribution from the source voltage distortion and the nonlinear loads for each harmonic at any location in the system are presented. A new method for the proper coordination of RMS protective devices with fundamental protective devices when current distortion is present is suggested. Two algorithms which can be used to calculate the current transmittances in steady state circuit analysis programs based on the frequency scan option in the EMTP are presented

Keywords

distribution networks; harmonic distortion; power system analysis computing; power system harmonics; power system protection; EMTP; RMS protection devices; current contribution calculation; current distortion; current levels; frequency scan option; harmonics; nonlinear loads; radial distribution system; responsive protection devices; source voltage distortion; steady state circuit analysis programs; transmittances; Circuit analysis; Circuit faults; Fault currents; Frequency; Harmonic distortion; Protection; Protective relaying; RLC circuits; Steady-state; Voltage;

fLanguage

English

Publisher

ieee

Conference_Titel

System Theory, 1997., Proceedings of the Twenty-Ninth Southeastern Symposium on

Conference_Location

Cookeville, TN

ISSN

0094-2898

Print_ISBN

0-8186-7873-9

Type

conf

DOI

10.1109/SSST.1997.581613

Filename

581613