Measurement of conducted electromagnetic noise generated by static var compensators
Date
1997-12
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Stellenbosch : Stellenbosch University
Abstract
ENGLISCH ABSTRACT: Conducted Electromagnetic Interference poses potentially serious problems to power line
carrier equipment used by electric utilities. The interference found by Eskom during measurements
at Perseus substation in 1985 provided the grounds for the study on which this
thesis is based. At Perseus up to 30 dB of noise was added in the power line carrier frequency
band, but fortunately the power line carrier and the noise lie at different frequencies and no
disruptive interference resulted. ·when much less noise was measured at the Impala SVC in
1995, this study was initiated to determine the reasons for the differences.
The generic noise characteristics of SVCs were investigated by building a scale model of the
SVC at Impala substation. The influence of the different components of an SVC on its noise
was studied, as well as various measurement techniques .
When the study began in January 1996, a ll indications were that the SVC planned for
Muldersvlei substation would be very similar to the Impala SVC. Because the Muldersvlei
substation is less than 20 km from Stellenbosch, it was thought that the results obtained
with the model could be compared with field measurements after commissioning of the new
SVC in March 1997. Later it was found that the Muldersvlei SVC circuit was different, but
these differences could not be implemented in the scale model at that stage .
Noise measurements at the Muldersvlei SVC substation were nevertheless performed . The
model and full-scale measurements were compared to assess the usefulness of such an SVC
model to predict the EMI characteristics of a full-scale SVC install ation. This was complemented
with some software simulations.
It was found that the SVC scale model is a useful tool to demonstrate the operation of an
SVC as we ll as predict the conducted el ectromagnetic noise generated by SVCs.
AFRIKAANSE OPSOMMING: Daar bestaan 'n moontlikheid van geleide Elektromagnetiese Interferensie met die kraglyn kommunikasie toerusting van Eskom. Hierdie moontlikheid is bevestig deur metings in die kraglyn draer (power line carrier) frekwensieband by die Statiese Var Kompenseerder ( Static Var Compensator) by Perseus substasie. Tot 30 dB ruis is bygevoeg deur die SVC . Die ruis en die kraglyn draer frekwensies verskil egter in so 'n mate dat die interferensie nie skadelik is nie. Toe laer ruisvlakke gemeet is by die Impala substasie SVC in 1995 , is hierdie ondersoek geloods om die verskille te ondersoek. Hierdie tesis is 'n ondersoek na die generiese ruis karakteristieke van SVCs. Met hierdie doel voor oe, is 'n fisiese skaalmodel van die Impala SVC gebou. Die invloed van die onderskeie komponente van 'n SVC kon met behulp van hierdie model bepaal word asook verskeie meetmetodes. Di e oorspronklike aanduidings in Januarie 1996 toe die navorsingsprojek begin is , was dat di e Muldersvlei SVC dieselfde as die I mpala SVC sou wees en daarom is die model ' n geskaleerde weergawe van die Impala SVC. Aangesien die Muldersvlei substasie ongeveer 20 km bui te Stellenbosch is, is besluit dat die model metings maklik met veld metings by die betrokke SVC verge lyk kan word. Teen die tyd dat die verskille tussen die twee SVCs bekend geword het, kon die model ni e meer verander word nie . Metings by die Muldersvlei s ubstasie is wel onderneem. Vergelykings tussen die model en vo lskaal metings is ook gedoen om die bruikbaarheid van sulk e skaalmodell e in die voorspelling van vo lskaa l SVCs se ruiskarakteristieke te bepaal. Sagteware simulasies is gedoen om hierdie r es ult ate te ondersteun. Daar is gevind dat die skaalmodel SVC 'n nuttige komponent is om die werking van ' n SVC te demonstreer sowel as om die geleide geraas van SVCs te voorspe l.
AFRIKAANSE OPSOMMING: Daar bestaan 'n moontlikheid van geleide Elektromagnetiese Interferensie met die kraglyn kommunikasie toerusting van Eskom. Hierdie moontlikheid is bevestig deur metings in die kraglyn draer (power line carrier) frekwensieband by die Statiese Var Kompenseerder ( Static Var Compensator) by Perseus substasie. Tot 30 dB ruis is bygevoeg deur die SVC . Die ruis en die kraglyn draer frekwensies verskil egter in so 'n mate dat die interferensie nie skadelik is nie. Toe laer ruisvlakke gemeet is by die Impala substasie SVC in 1995 , is hierdie ondersoek geloods om die verskille te ondersoek. Hierdie tesis is 'n ondersoek na die generiese ruis karakteristieke van SVCs. Met hierdie doel voor oe, is 'n fisiese skaalmodel van die Impala SVC gebou. Die invloed van die onderskeie komponente van 'n SVC kon met behulp van hierdie model bepaal word asook verskeie meetmetodes. Di e oorspronklike aanduidings in Januarie 1996 toe die navorsingsprojek begin is , was dat di e Muldersvlei SVC dieselfde as die I mpala SVC sou wees en daarom is die model ' n geskaleerde weergawe van die Impala SVC. Aangesien die Muldersvlei substasie ongeveer 20 km bui te Stellenbosch is, is besluit dat die model metings maklik met veld metings by die betrokke SVC verge lyk kan word. Teen die tyd dat die verskille tussen die twee SVCs bekend geword het, kon die model ni e meer verander word nie . Metings by die Muldersvlei s ubstasie is wel onderneem. Vergelykings tussen die model en vo lskaal metings is ook gedoen om die bruikbaarheid van sulk e skaalmodell e in die voorspelling van vo lskaa l SVCs se ruiskarakteristieke te bepaal. Sagteware simulasies is gedoen om hierdie r es ult ate te ondersteun. Daar is gevind dat die skaalmodel SVC 'n nuttige komponent is om die werking van ' n SVC te demonstreer sowel as om die geleide geraas van SVCs te voorspe l.
Description
Thesis (MEng) -- Stellenbosch University, 1997.
Keywords
Electromagnetic noise, Power electronics, Electronic circuits -- Noise, Electromagnetic interference, Capacitors, Synchronous, UCTD