Original scientific paper
Dielectric, Switching and System Requirements under Out-of-Phase Conditions, during Synchronisation and under Comparable Stresses
A. L.J. Jansen
; On behalf of CIGRE WG A3.13
F. Iliceto
; On behalf of CIGRE WG A3.13
Q. Bui-Van
; On behalf of CIGRE WG A3.13
S. Morais
; On behalf of CIGRE WG A3.13
M. Waldron
; On behalf of CIGRE WG A3.13
B. Middelton
; On behalf of CIGRE WG A3.13
Abstract
Recent developments in electrical networks can increase the probability of out-of-phase switching and
dielectric stresses being applied to open circuit-breakers, due to asynchronous systems at both sides.
This report presents a systematic study of TRV-stresses associated with generator separation and
system separation. TRV peak values are higher than required in the Standards, even for relatively
small out-of-phase angles (75º to 90º), and the dielectric stresses are high with respect to the shortduration
power frequency withstand voltages across a circuit-breaker open contacts, especially taking
into consideration the external insulation under pollution and ageing processes. To the opinion of the
authors, the Standards should be revised to give users clear and adequate guidance on the assessment
and specification of TRV-values and dielectric withstand requirements under out-of-phase conditions.
Keywords
Out-of-phase; synchronisation; TRV; RRRV; First-Pole-to-Clear Factor (fpcf); longitudinal dielectric stress
Hrčak ID:
198424
URI
Publication date:
19.6.2017.
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