Work Experience

  • Todate 2001

    Prof. Dr.

    Yakın Doğu Üniversitesi, Elektrik-Elektronik Mühendisliği

  • Todate 2001

    Prof. Dr.

    Near East University, Electrical and Electonic Engineering

  • 2001 1990

    Doç. Dr.

    Yakın Doğu Üniversitesi, Elektrik-Elektronik Mühendisliği

  • 2001 1990

    Assoc. Prof. Dr.

    Near East University, Electrical and Electonic Engineering

  • 1988 1987

    Assist. Prof. Dr.

    Middle East Technical University, Electrical and Electronic Engineering

  • 1988 1987

    Yrd. Doç. Dr.

    Orta Doğu Teknik Üniversitesi, Elektik-Elektronik Mühendisliği

Education & Training

  • Ph.D. 1987

    Electrical-Electronic Engineering

    Middle East Technical University

  • Master1982

    Electrical-Electronic Engineering

    Middle East Technical University

  • Bachelor1979

    Electrical-Electronic Engineering

    Middle East Technical University

Honors, Awards and Grants

Research Projects

  • image

    Ark Fırınları'nda Güç Kompansazyon

    Reactive Power Compensation in Arc Furnaces at the factories of MKEK, Ankara

    Middle East Technical University Power Systems Goup Project

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Surface Charging Of Spacers Under DC Stressing

Conference Paper Benetton Editore-Padova, Volume 1, Issue 1, 1988, Pages 295-729

Abstract

The successful use of compressed SF6 insulation in HVAC apparatus over the recent year has stimulated various research and development programs into the future applications (DC-GIS) and transmission lines (DC-CGIT) (1). One of the problems with HVDC insulation however is the surface charging of spacers which are used for supporting high-voltage conductors. Such spacers, once charged, can remain so for extensive periods of time and may result in a weakness in the insulation integrity of the system by causing field enhancement. Although much work has been reported on the surface charging of spacers (2,3) still the characteristics of charge accumulation under DC stressing are not well know. A knowledge on the charging characteristics of spacers may however be useful in minimizing the amount of charge accumulation and hence its adverse effects on the performance of the system. The present paper reports on the spatiotemporal development of surface charge on spacers under DC stressing, for a time span of several hours. Measurement of the temporal development of charge was performed at different stress levels and the variation of peak charge density with applied voltage was studied. Various factors which may affect the charge accumulation pattern were also investigated.


Özet

Measurement Of The Temporal Decay Of Charges On Insulator Surfaces

Original Article Pergamon Press, Volume 1, Issue 1, 1987, Pages 553-559

Abstract

This paper reports measurements of the decay of surface charges on insulator surfaces. A comparison is made of the different effects of surface conductivity and of the drift of ions created in the surrounding gas by background radiation on the rate of neutralisation of the surface charge. A novel charge measurement system which reduces the drift error to 60 fC a 60-sec scan is also reported.


Özet

Spatio-temporal Development of Surface Charges on Spacers Stressed with dc Voltages

Original Article IEEE Transactions on Electrical Insulation, Volume 25, Issue 3, 1990, Pages 515-615

Abstract

The development of surface charge on a right-cylindrical spacer under different dc stress levels was measured in SF6 for several h. These dc voltage stress levels were below the stresses where partial discharges with ac voltage generally occur. The measureements indicate that charges are mainly deposited on one side only of the spacer and are predominantly of opposite polarity to that of the applied voltage. The charge and its area increase with time and saturate. Typical saturation times are approximately 3 and 9 h for 10 kV and 5 kV respectively. Magnitudes of saturated charge increase linearly with applied voltage. Various factors which may affect charge accumulation pattern were also investigated. measurements show that charge depositions on a spacer are influenced insignificantly by y-irradiation or a change of gas from SF6 to air. However charge depositions are influenced by surface conductance of the spacer. Charging of spacer is negligible when stressed with ac and impulse voltage with peak voltages in a similar range to the dc levels used.


Özet

The behavior of N-2+SF6 gas mixtures subjected to orthogonal electric and magnetic fields .

Original Article IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION , Volume 13, Issue 2, 2006, Pages 257-263

Abstract

The limiting equivalent electric fields in N-2 + SF6 binary gas mixtures due to Townsend discharges are evaluated directly from a Monte-Carlo simulation when the mixture is subjected to orthogonal electric and magnetic fields. Along with the limiting equivalent electric fields, transverse and perpendicular drift velocities, electron mean energies and collision frequencies are also determined within the scope of the Monte-Carlo simulation. The equivalent reduced electric field (EREF) concept for the corresponding limiting electric fields is also investigated for the calculated mean energy levels and collision frequencies. The EREF values are found to be in good agreement with the previously published limiting electric field data.


Özet

Effective ionization coefficients and transport parameters in ultradilute SF6+N-2 mixtures

Original Article IEEE Transactions On Plasma Science, Volume 35, Issue 5, 2007, Pages 1210-1214

Abstract

The effective ionization coefficients in ultradilute SF6 + N-2 gas mixtures are calculated from a Monte,Carlo technique over the range 100 <= E/N <= 270 Td together with electron drift velocities and pulsed Townsend mean energies. SF6 contents in the mixtures of 0.1%, 0.3%, 0.5%, 0.7%, and 1% are considered. The effective ionization coefficients decrease with the increase of the SF6 concentration in the mixtures at a given E/N, while the variation of the drift velocities and pulsed Townsend mean energies with respect to SF6 concentrations is relatively constant in the E/N range of this paper.


Özet

Boltzmann Analysis of Electron Swarm Parameters in Binary CF4 + Ar Mixtures

Original Article IEEE Transactions On Dielectrics and Electrical Insulation , Volume 20, Issue 1, 2013, Pages 98-103

Abstract

The electron swarm parameters, namely electron mean energy, drift velocity, effective ionization coefficient and limiting values of number density reduced electric fields, E/N, are calculated in CF4+Ar mixtures CF4 concentrations that vary from 2 to 100 % over a range of E/N from 50 Td by solving Boltzmann's equation was solved using finite difference method under steady-state Townsend condition. one of the most important results of this study indicated that at higher E/N values inelastic processes due to argon began to control the energy thus leading this binary mixture act essentially like pure argon.


Özet

Effective ionization coefficients, limiting electric fields and electron energy distrubitions in CF31 + CF4 + Ar ternary gas mixtures of CF3I + CF4 +Ar in the E/N range of 100-700 Td employing a teo-term solition of the Boltzmann equation. In the ternary mixture, CF3I component is increased while the CF4 compenent is reduced accordingly and the 40 % Ar component is kept constant. It is seen that the electronegativity of the mixture increases with increased CF3I content and effective ionization coefficients decreases while the limiting electric field values increase. Synergism in the mixture is also evaluated in percentage using the limiting electric field values obtained. Furthermore, it is possible to control the mean electron energy in the ternary mixture by changing the content of CF3I component.

Original Article AIP Publishing, Volume 23, Issue 7, 2016, Pages -

Abstract

This paper reports


Özet

Currrent Teaching

  • 2016 GÜZ

    CIRCUIT THEORY I

    .

  • 2016 GÜZ

    ELECTRICAL CIRCUIT THEORY

Teaching History

  • 2015 YAZ

    CIRCUIT THEORY II

    .

  • 2014 BAHAR

    ELECTROMECHANICAL ENERGY CONVERSION II

    .

  • 2014 YAZ

    CIRCUIT THEORY II

    .

  • 2015 BAHAR

    CIRCUIT THEORY I

    .

  • 2015 GÜZ

    CIRCUIT THEORY I

    .

  • 2014 BAHAR

    ELECTROMECHANICAL ENERGY CONVERSION II

  • 2015 BAHAR

    ELECTROMECHANICAL ENERGY CONVERSION II

  • 2014 BAHAR

    CIRCUIT THEORY II

    .

  • 2015 BAHAR

    CIRCUIT THEORY II

    .

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