Original scientific paper
PUSHING THE BOUNDARIES OF INDUCTIVE VOLTAGE TRANSFORMER DESIGN
Igor Žiger
; Končar - Instrument transformers Inc.
Danijel Krajtner
; Končar - Instrument transformers Inc.
Zvonimir Ubrekić
; Končar - Instrument transformers Inc.
Abstract
Designing inductive voltage transformers for the highest voltage levels (550 kV and above) is a
true challenge indeed. The main reason for this is their complex internal R-L-C structure, including an
insulating system which needs to be resistant to all types of overvoltages and consequent dielectric stress
it can encounter during its lifetime. This is why it is necessary to verify behavior of such transformers
during the design process, and under four sets of standard test overvoltage types; the Power Frequency
Withstand Voltage (PFWV), the Lightning Impulse Withstand Voltage (LIWV, i.e. BIL), Chopped Impulse
Withstand Voltage (CIWV) and the Switching Impulse Withstand Voltage (SIWV).
The main idea of the paper is to demonstrate that by understanding the influence of crucial
parameters of the appropriate equivalent diagram on the voltage distribution across the active part of the
transformer, it is possible to define the overall design of inductive voltage transformers so that they can satisfy
even the most rigorous insulation requirements, thus pushing the boundaries of design even further.
Keywords
Hrčak ID:
199210
URI
Publication date:
15.8.2017.
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