Conference Paper

Voltage transformer frequency response. Measuring harmonics in Norwegian 300 kV and 132 kV power systems

SINTEF, Trondheim;
DOI: 10.1109/ICHQP.1998.760148 Conference: Harmonics And Quality of Power, 1998. Proceedings. 8th International Conference on, Volume: 2
Source: IEEE Xplore

ABSTRACT Measuring harmonics in high voltage power systems with inductive
and in particular capacitive voltage transformers, CVTs, may cause large
errors. Test carried out by The Norwegian National Grid Company
(Statnett), Bergenshalvoens Kommunale Kraftselskap (BKK) and The
Norwegian Electric Power Research Institute (now SINTEF Energy Research)
revealed errors from 80% to +1200% (0,2-12 pu) of correct values.
Inductive voltage transformers did have a relatively small error up to
29th harmonic (1450 Hz) while capacitive voltage transformers
had large errors at a few hundred Hz. Carrying out calibration tests on
voltage transformers and capacitive voltage transformers in particular
may correct most of the errors. Still inductive voltage transformers
should be preferred for harmonic measurements where possible

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