- Type of paper
: Paper in journal
Title: Measuring transformers-components of the protection system
- Authors:
- Poljak, Miroslav (84806)
- Bojanić, Boris (191640)
Journal: Energija
Number: 5
ISSN: 0013-7448
Volume: 40
Year: 1991
Pages: from 327 to 332
Number of references: 5
Language: hrvatski
Summary: The basic characteristics as well as the manner of
specificationfor current and voltage transformer are described including
areview of the requirements defined by new IEC Standards.Significant
characteristics of Končar measuring transformers areassessed regarding
protection systems.
Keywords: protective current transformer, protective voltage transformer, capacitor voltage transformer, protection, high-impedance protection
- Type of paper
: Paper in journal
Title: Equipment for measuring transformer explosion protection
- Authors:
- Poljak, Miroslav (84806)
- Katunarić, Neven (84663)
- Bojanić, Boris (191640)
Journal: Energija
Number: 5
ISSN: 0013-7448
Volume: 41
Year: 1992
Pages: from 295 to 301
Number of references: 3
Language: hrvatski
Summary: Basic characteristics of the equipment for measuring
transformerprotection from explosion are given. The equipment works on
theprinciple of registration of the current increase through themain
insulation of the measuring transformer, and its basefunction is the
signalisation of the fault in the first degresand finally the lock-out of
the faulty transformer in the seconddegree. Also the results of the
prototype test are given.
Keywords: measuring transformer, current transformer, voltage transformer,protective device
- Type of paper
: Paper in proceedings
Title: Behaviour of current transformers at fast transient in
power system
- Authors:
- Poljak, Miroslav (84806)
Proceedings title: Zbornik radova XX savjetovanja elektroenergetičara Jugoslavije Grupa 12 Transfor
Language: hrvatski
Place: Zagreb
Year: 1991
Pages: from 0 to 0
Meeting: XX Savjetovanja elektroenergetičara Jugoslavije
Held: from 04/22/91 to 04/26/91
Summary: Investigations of the distribution of high frequency
currents andvoltages within insulating system while the disconnector is
inoperation are described. Futher, test method and results of thefast
transient test of 400 kV inverse type current transformerare described.
That test belong to a group special tests whosecontent and criteria are
subject of IEC discussion.
Keywords: measuring transformer,current transformer, test, fast transient
- Type of paper
: Paper in proceedings
Title: Highfrequency overvoltages in instrument transformers
secondary circuit
- Authors:
- Poljak, Miroslav (84806)
Proceedings title: Zbornik radova I savjetovanja HK CIGRE
Language: hrvatski
Place: Zagreb
Year: 1993
Pages: from 221 to 229
Meeting: I savjetovanje HK CIGRE
Held: from 10/10/93 to 10/13/93
Summary: The problems related to transient overvoltages transfered
toinstrument transformers secondary circuit have resulted in aproposal of a
method for laboratory testing of theirelectromagnetic compatibility. The
proposed test method and itsapplicability is critically reviewed. The test
results of acurrent transformer for Um=123 kV indicate that an
earthingsystem ist most important factor that effects the
transformerelectromagnetic compatibility. Proposal of instrument
transformerearthing system is disussed in a separate section.
Keywords: instrument transformer, highfrequency overvoltage, testing, electreomagnetic compatibility, earthing
- Type of paper
: Paper in proceedings
Title: A New Concept of Combined Transformers
- Authors:
- Poljak, Miroslav (84806)
- Bojanić, Boris
- Tomašević, Josip
- Hafner, Tomislav
Proceedings title: Zbornik radova II savjetovanja Hrvatskog komiteta CIGRE
Language: hrvatski
Place: Zagreb
Year: 1995
ISBN/ISSN: 953-6408-01-5
Pages: from 85 to 93
Meeting: II savjetovanje Hrvatskog komiteta CIGRE
Held: from 05/14/95 to 05/18/95
Summary: The basic characteristics of a new concept of combined
transformers consisting of an inverse current transformer and a voltage
transformer with open core, are described. The results of the research and
testing of impulse and a.c. voltage distribution, accuracy class, influence
of the current transformer on the voltage transformer and vice versa are
given. Thanks to its technologicality and simplicity, the new concept
allows the commercial manufacture of combined transformers for the highest
equipment voltages up to 420 kV inclusive.
Keywords: instrument transformer, combined transformer, voltage distribution, accuracy class
- Type of paper
: Prototype
Title: Combined Current and Voltage Transformer For High Voltage
- Authors:
- Bojanić, Boris
- Hafner, Tomislav
- Poljak, Miroslav (84806)
- Tomašević, Josip
Institution of application: Državni zavod za patente Republike Hrvatske
Date of application: 04/07/93
Registration number of application: P930794A
Language: hrvatski
Summary: The combined current and voltage transformer for high
voltages is designed so that the current transformer is made as
inverse-type transformer with cores and secondary windings placed in its
head (upper housing). The voltage transformer is made with open magnetic
core, which is with its secondary windings placed vertically along the
height of the combined transformer within the metal tube, which is at the
same time the mechnical base of the current transformer, and through it
secondary terminals of the current transformer pass. The primary winding is
made of several sections, which are applied to the edges of main isulation
wound on the metal tube, and placed vertically within the post insulator.
Keywords: instrument transformer, combined transformer, voltage distribution, accuracy class
