Güven Kömürgöz - Academia.edu (original) (raw)

Papers by Güven Kömürgöz

Research paper thumbnail of Optimization and analysis of tapping position on leakage reactance of a two winding transformer

Alexandria Engineering Journal

Research paper thumbnail of Contributions To The Calculation Of Winding Temperature Rise Of The Naturally Cooled Dry Type Power Transformers

Tez (Doktora) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2002Thesis (PhD) -- İstan... more Tez (Doktora) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2002Thesis (PhD) -- İstanbul Technical University, Institute of Science and Technology, 2002Bu çalışmada; kendi kendine soğuyan kuru tip bir güç transformatöründe sonlu elemanlar yöntemine dayanan Ansys paket programı ile alt ve üst gerilim sargısı ve çekirdekten oluşan transformatörün bir bacağına ilişkin sıcaklık dağılımı çıkarılmıştır. Yüksekliği 537,6.10-3 m olan sargılar dilimli, silindirik sargıdır. Akışkan özelliklerinin sıcaklıkla değişmesinden dolayı akışkan ve sıcaklık beraber düşünülerek çözülmüştür. Sargılar ve çekirdeğin sıcaklık dağılımlarının yanında bu parçaların etrafında bulunan havanın hareketi ve sıcaklığı da bulunmuştur. Yüksek gerilim sargısının yüksekliği boyunca sıcaklık dağılım eğrisi çıkartılarak, en çok ısınan noktanın yeri ve büyüklüğü belirlenmiştir. Sıcaklık dağılım eğrisi deneysel çalışmayla elde edilen eğriyle karşılaştırılmıştır. Elde edilen sonuçlar deneysel çalışmayla bulunan s...

Research paper thumbnail of DQM Application on Classical Problem “Stagnation Point Flow”

International Journal of Mechanical Engineering and Robotics Research

In this study, a classical problem stagnation point flow was revisited by using powerfull enough ... more In this study, a classical problem stagnation point flow was revisited by using powerfull enough semi numerical analytical technique DQM. A general expression of stagnation point flow is obtained. This equation solved with differential quadrature method (DQM) and Galerkin method. It is seen that obtained results are very closed to each other. But using DQM is more practical and faster than Galerkin. Because polynomial fitting in Galerkin method requires much more time than DQM  Index Terms-component; stagnation point flow, differential quadrature method, galerkin method I.

Research paper thumbnail of A simple analytical method for accurate prediction of the leakage reactance and leakage energy in high voltage transformers

Journal of King Saud University - Engineering Sciences

Research paper thumbnail of Investigating the Effect of Axial Displacement of Transformer Winding on the Electromagnetic Forces

2020 7th International Conference on Electrical and Electronics Engineering (ICEEE)

The working of the electrical network mainly depends on the working of the power transformer. Sev... more The working of the electrical network mainly depends on the working of the power transformer. Several important factors of the electrical power system such as efficiency, safety, and total losses are also affected by the power transformer. One of the most important factors for the designing of the power transformer is electromagnetic forces. In this paper, electromagnetic forces of the power transformer are calculated by using the finite element method with the help of two-dimensional models. When the transformer's windings are in the original initial designing position, the current and electromagnetic forces of the routine and short-circuit circumstances are familiar to the transformer designers. However, the effect of the displacement of the transformer's windings on the electromagnetic forces is not well known to the transformer designers. In this work, electromagnetic forces during the non-displaced (normal conditions) and displaced windings of the transformer are examined by using finite element analysis. The main aim of this study is to investigate the radial and axial force of the displaced winding. Numerical results of the radial forces of the non-displaced windings are also compared with the analytical technique.

Research paper thumbnail of Analysis and optimization of leakage impedance in a transformer with additional winding: A numerical and experimental study

Alexandria Engineering Journal

Research paper thumbnail of Design Of Permanent Magnet Machines With Different Rotor Type

This paper presents design, analysis and comparison of the different rotor type permanent magnet ... more This paper presents design, analysis and comparison of the different rotor type permanent magnet machines. The presented machines are designed as having same geometrical dimensions and same materials for comparison. The main machine parameters of interior and exterior rotor type machines including eddy current effect, torque-speed characteristics and magnetic analysis are investigated using MAXWELL program. With this program, the components of the permanent magnet machines can be calculated with high accuracy. Six types of Permanent machines are compared with respect to their topology, size, magnetic field, air gap flux, voltage, torque, loss and efficiency. The analysis results demonstrate the effectiveness of the proposed machines design methodology. We believe that, this study will be a helpful resource in terms of examination and comparison of the basic structure and magnetic features of the PM (Permanent magnet) machines which have different rotor structure.

Research paper thumbnail of Permanent magnet synchronous motor design, production and experimental verification for compressor application

2016 National Conference on Electrical, Electronics and Biomedical Engineering (ELECO), 2016

In this study, 3 phase Permanent Magnet Synchronous Motor (PMSM) for refrigerator application was... more In this study, 3 phase Permanent Magnet Synchronous Motor (PMSM) for refrigerator application was designed and prototyped, experimental results carried out and validated. Design criteria was determined by taking into consideration constrains of the compressor. Proper slot/pole combination was identified and previously untested slot/pole combination was chosen as target. Speed® software was used for pre-design stage, optimization studies and detailed finite element analysis (FEA) was completed Maxwell® 3D software. The prototype of the motor was manufactured and motor performance was verified experimentally.

Research paper thumbnail of Electromagnetic and Thermal Analysis of a Domestic Induction Cooker Coil

2019 4th International Conference on Power Electronics and their Applications (ICPEA), 2019

In this study, induction cookers used in domestic applications are investigated. A commercially a... more In this study, induction cookers used in domestic applications are investigated. A commercially available induction cooker is chosen and a 3-dimensional finite element model of the cooker is investigated for electromagnetic analysis by using ANSYS electronics desktop. Magnetic flux density distribution of the bottom of the pan is also obtained. By using finite element method results, thermal analysis of the induction cooker is obtained by using ANSYS Fluent via ANSYS Workbench. Lastly, an experimental test was conducted to see the thermal characters of the induction cooker. The finite element method results are also compared with the experimental results.

Research paper thumbnail of Design of 75 kW asynchronous motor for electric vehicle applications

2016 National Conference on Electrical, Electronics and Biomedical Engineering (ELECO), 2016

In this study, the design of 75kW (continuous 50kW) squirrel cage induction motor for electric ve... more In this study, the design of 75kW (continuous 50kW) squirrel cage induction motor for electric vehicle applications is presented. First, the main design constraints and performance criteria are determined. Depending on these constraints and criteria, computer aided design of the motor is performed. Then, the electrical, magnetic and performance analyses of the motor are performed. The analysis results show that the designed motor satisfies the desired power specifications and the design performance criteria.

Research paper thumbnail of Investigating the Effect of Tap Insertion in Concentric Coil Transformer on the Electromagnetic Forces using Magnetostatic analysis

2020 International Conference on Electrical, Communication, and Computer Engineering (ICECCE), 2020

In the manufacturing of the concentric coil transformer, stability and working are mainly affecte... more In the manufacturing of the concentric coil transformer, stability and working are mainly affected by the insertion of the regulating tap in the transformer. The tap insertion can cause asymmetry on the transformer windings and increase the radial and axial forces. In this paper, a numerical approach is used to determine the electromagnetic forces in the concentric coil transformer with the different tap windings setup. Five different tapping configurations are investigated for the calculation of the electromagnetic forces. The classical and most commonly used analytical method is also compared with the numerical results of the first condition. Analytical results show a good agreement with the finite element method results. This work will be helpful to the transformer manufacturers and give great knowledge about the insertion of the tap in the concentric coil transformer.

Research paper thumbnail of Kendi Kendine Soğuyan Kuru Tip Güç Transformatörlerinde Sargı Isınma Hesabına Katkılar

Research paper thumbnail of Kendi Kendine Soğuyan Kuru Tip Güç Transformatörlerinde Sıcaklık Dağılımının Belirlenmesi

Yuksek gerilim sargisi yuksekligi 537,6.10-3 m olan, 13 bobinden meydana gelmis, dilimli, silindi... more Yuksek gerilim sargisi yuksekligi 537,6.10-3 m olan, 13 bobinden meydana gelmis, dilimli, silindirik sargili kendi kendine soguyan kuru tip bir guc transformatorunde Ansys sonlu elemanlar programi ile sicaklik dagilimi cikarilmistir. Alt, ust gerilim sargilari ve cekirdek ayri alinarak sargilar ve cekirdek arasindaki yag kanalinin sogutma etkisi de dikkate alinmistir. Akiskan ozelliklerinin sicaklikla degismesinden dolayi akiskan ve sicaklik beraber cozulmustur. Sargilar ve cekirdegin sicaklik dagilimlarinin yaninda bu parcalarin etrafinda bulunan havanin hareketi ve sicakligi da bulunmustur. En cok isinan noktanin yeri ve buyuklugu belirlenmistir. Yuksek gerilim sargi yuksekligi boyunca sicaklik dagilim egrisi cikartilmistir. Sicaklik dagilim egrisi deneysel calismayla elde edilen egriyle karsilastirilmistir. Anahtar Kelimeler: Transformator, sargi, sicak nokta sicakligi, sicaklik dagilimi, hiz dagilimi.

Research paper thumbnail of Design optimisation for distance between additional and tap winding in high‐voltage transformers

High Voltage, 2020

The transformer is one of the main components in the power network and transformer windings are o... more The transformer is one of the main components in the power network and transformer windings are one of the most expensive elements in the power transformer. Optimisation of winding distances is one of the most important parameters during the manufacturing of transformer. The distance between the windings in the two winding transformers is well known to transformer designers and manufacturers. However, insulation of the high voltage transformer with additional winding and tap winding is still a major problem for transformer designers. In this study, the additional winding to tap winding distance optimisation is made for a high voltage power transformer. Optimisation of the transformer's windings just not minimises the cost of the transformer but also increases the lifetime of the transformer. With additional winding and tap winding in high-voltage transformers, insulation distance is a major concern for minimising the cost and size of the high voltage transformer. In this study, an approach is made to balance the cost, size, and safety of high voltage transformers. The optimised distance and position between tap winding and additional winding are determined by using the finite element analysis. The finite element method results were also verified by making a prototype transformer.

Research paper thumbnail of Electromagnetic and Thermal Design/Analysis of an Induction Motor for Electric Vehicles

International Journal of Mechanical Engineering and Robotics Research, 2019

The most commonly used electrical machine is the induction machine since it is durable, easy to m... more The most commonly used electrical machine is the induction machine since it is durable, easy to manufacture and control. Additionally, it requires less maintenance, and responses different loads. In this study, the design of 115kW (continuous 85kW) squirrel cage induction motor is presented for electric vehicle applications. Main design constraints and performance criteria of the motor are determined and depending on these values, computer aided design is performed. In the design procedure, initially, an analytical design of the electric vehicle motor is performed depending on specified design criteria. Then, the analytical design is verified by using finite element analysis. Depending on the obtained results in electromagnetic analyses, the squirrel cage induction motor is modified in order to improve the obtained performance further. The electromagnetic and thermal analyses of the designed motor are performed by using Maxwell and ANSYS software programs, respectively. Designed motor will stand maximum allowable temperature based on temperature rise of the used insulation class. The analyses results show that the designed motor satisfies the design criteria.  Index Terms-Induction motor, electric vehicle, thermal analysis, electromagnetic analysis I.

Research paper thumbnail of Electromagnetic and Thermal Analysis/Design of an Induction Motor for Electric Vehicles

International Journal of Mechanical Engineering and Robotics Research, 2018

Induction machines are the most commonly used electrical machines in applications, since they are... more Induction machines are the most commonly used electrical machines in applications, since they are durable, easy to manufacture and control. Additionally, they require less maintenance and response different loads. In this study, the design of 115kW (continuous 85kW) squirrel cage induction motor is presented for electric vehicle applications. Main design constraints and performance criteria of the motor are determined, and the computer-aided design is performed depending on these values. In the design procedure, initially, an analytical design of the electric vehicle motor is performed depending on specified design criteria. Then, the analytical design is verified by using finite element analyses. Depending on the obtained results in electromagnetic analyses, the squirrel cage induction motor for electric vehicle is modified in order to improve the obtained performance further. The electromagnetic and thermal analyses of the designed motor are performed by using Maxwell and ANSYS software programs, respectively. The insulation class of the designed motor is determined by considering the maximum allowable temperature criterion. The analyses results show that the designed motor satisfies design constraints and performance criteria.

Research paper thumbnail of Investigation of winding MMF harmonic reduction methods in IPM machines equipped with FSCWs

International Transactions on Electrical Energy Systems, 2018

In this paper, implementation of fractional-slot concentrated windings (FSCWs) into an interior p... more In this paper, implementation of fractional-slot concentrated windings (FSCWs) into an interior permanent magnet (IPM) machine, designed by using the same geometrical and operational specifications as Toyota Prius 2010 IPM machine, has been presented. In detail, the Toyota Prius's IPM equipped with integer-slot distributed windings has been considered as a reference machine. Then the geometry of the stator has been adequately modified in other five models to equip FSCWs and adopt different magnetomotive force (MMF) reduction methods. It has been validated that the FSCW technique causes a significant increase in the rotor losses due to increase in the rate of the total harmonic distortion of the MMF harmonics. To reduce the effect of these harmonics, different MMF harmonic reduction methods including phase-winding coils with different number of turns, multilayer winding with phase shifting, and stator with flux barriers have been investigated. To reveal the effectiveness of the investigated MMF harmonic reduction methods, the key thermal and electromagnetic performance characteristics including torque, torque ripple, power losses, and efficiency have been numerically calculated by finite element method and have eventually been compared.

Research paper thumbnail of Application of Weibull Distribution Method for Aircraft Component Life Estimation in Civil Aviation Sector

Journal of Traffic and Logistics Engineering, 2017

The continuous monitoring of fleet reliability has been made compulsory by the aviation authoriti... more The continuous monitoring of fleet reliability has been made compulsory by the aviation authorities, due to the maintenance program for civil aviation aircrafts has been prepared on MSG-3 philosophy. In this context, task card and maintenance intervals must be set according to the reliability of aircraft components and systems. Approximately 90 percent of the maintenance programs prepared according to the MSG-3 philosophy contain task cards for finding defects or faults, and these do not have a relevant use in the absence of a defect or fault. In this study, reliability of the aircraft parts is estimated according to the Weibull distribution by using maintenance data, and the probability of failure for each part is calculated.  Index Terms-w eibull, w eibull analysis, civil avation, MSG-3, reliability analysis, life data analysis I.

Research paper thumbnail of Electrical design and testing of a 500 kW doubly fed induction generator for wind power applications

TURKISH JOURNAL OF ELECTRICAL ENGINEERING & COMPUTER SCIENCES, 2017

In this study, the electrical design and testing of a 500 kW doubly fed induction generator (DFIG... more In this study, the electrical design and testing of a 500 kW doubly fed induction generator (DFIG) is presented, developed in the context of the MILRES (Turkish National Wind Energy Systems) Project. The main objective of the MILRES Project is to encourage locally produced equipment for wind power systems. Therefore, in the DFIG design, the standard construction capabilities of the local machine manufacturers are especially taken into consideration. In this way, it is aimed that the designed DFIG can easily and cost-effectively be manufactured by local machine manufacturers in Turkey. In the DFIG design procedure, initially, an analytical design of the DFIG is performed depending on specified design criteria. Then the analytical design is verified by using finite element analysis. Depending on the obtained results in electromagnetic analyses, the DFIG design is modified in order to improve the obtained performance further. Finally, the designed DFIG is manufactured and its performance tests are performed at three different operating points. The test results verify the analyses results and show that the designed DFIG satisfies the desired performance criteria.

Research paper thumbnail of Influence of PV Penetration on Distribution Transformer Aging

Journal of Clean Energy Technologies, 2017

Increasing power demand urged countries to seek out energy sources with higher efficiency and low... more Increasing power demand urged countries to seek out energy sources with higher efficiency and lower cost than the existing ones. Solar energy is an effective alternative source to the traditional energy sources. The photovoltaic distributed generation is an effective energy source since it combines the advantages of smart grid and solar energy. Depending on the season, photovoltaic generation connected to the distribution network shows different penetration that affects the network load distribution, which can lead to excessive loading at lines, cables and transformers in distribution systems. As the life expectancy of transformers and cables in the distribution system depends on the operating conditions, overloading caused by penetration of distributed photovoltaic systems speeds up the aging of the components. Therefore, investigating the effects of photovoltaic systems on the aging is important for providing insight on the efficient use of components in the distribution transformers. In this study, the impact of loss of life on the distribution transformer photovoltaic production is examined by taking the seasonal influences into account from the point of view of a consumer.

Research paper thumbnail of Optimization and analysis of tapping position on leakage reactance of a two winding transformer

Alexandria Engineering Journal

Research paper thumbnail of Contributions To The Calculation Of Winding Temperature Rise Of The Naturally Cooled Dry Type Power Transformers

Tez (Doktora) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2002Thesis (PhD) -- İstan... more Tez (Doktora) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2002Thesis (PhD) -- İstanbul Technical University, Institute of Science and Technology, 2002Bu çalışmada; kendi kendine soğuyan kuru tip bir güç transformatöründe sonlu elemanlar yöntemine dayanan Ansys paket programı ile alt ve üst gerilim sargısı ve çekirdekten oluşan transformatörün bir bacağına ilişkin sıcaklık dağılımı çıkarılmıştır. Yüksekliği 537,6.10-3 m olan sargılar dilimli, silindirik sargıdır. Akışkan özelliklerinin sıcaklıkla değişmesinden dolayı akışkan ve sıcaklık beraber düşünülerek çözülmüştür. Sargılar ve çekirdeğin sıcaklık dağılımlarının yanında bu parçaların etrafında bulunan havanın hareketi ve sıcaklığı da bulunmuştur. Yüksek gerilim sargısının yüksekliği boyunca sıcaklık dağılım eğrisi çıkartılarak, en çok ısınan noktanın yeri ve büyüklüğü belirlenmiştir. Sıcaklık dağılım eğrisi deneysel çalışmayla elde edilen eğriyle karşılaştırılmıştır. Elde edilen sonuçlar deneysel çalışmayla bulunan s...

Research paper thumbnail of DQM Application on Classical Problem “Stagnation Point Flow”

International Journal of Mechanical Engineering and Robotics Research

In this study, a classical problem stagnation point flow was revisited by using powerfull enough ... more In this study, a classical problem stagnation point flow was revisited by using powerfull enough semi numerical analytical technique DQM. A general expression of stagnation point flow is obtained. This equation solved with differential quadrature method (DQM) and Galerkin method. It is seen that obtained results are very closed to each other. But using DQM is more practical and faster than Galerkin. Because polynomial fitting in Galerkin method requires much more time than DQM  Index Terms-component; stagnation point flow, differential quadrature method, galerkin method I.

Research paper thumbnail of A simple analytical method for accurate prediction of the leakage reactance and leakage energy in high voltage transformers

Journal of King Saud University - Engineering Sciences

Research paper thumbnail of Investigating the Effect of Axial Displacement of Transformer Winding on the Electromagnetic Forces

2020 7th International Conference on Electrical and Electronics Engineering (ICEEE)

The working of the electrical network mainly depends on the working of the power transformer. Sev... more The working of the electrical network mainly depends on the working of the power transformer. Several important factors of the electrical power system such as efficiency, safety, and total losses are also affected by the power transformer. One of the most important factors for the designing of the power transformer is electromagnetic forces. In this paper, electromagnetic forces of the power transformer are calculated by using the finite element method with the help of two-dimensional models. When the transformer's windings are in the original initial designing position, the current and electromagnetic forces of the routine and short-circuit circumstances are familiar to the transformer designers. However, the effect of the displacement of the transformer's windings on the electromagnetic forces is not well known to the transformer designers. In this work, electromagnetic forces during the non-displaced (normal conditions) and displaced windings of the transformer are examined by using finite element analysis. The main aim of this study is to investigate the radial and axial force of the displaced winding. Numerical results of the radial forces of the non-displaced windings are also compared with the analytical technique.

Research paper thumbnail of Analysis and optimization of leakage impedance in a transformer with additional winding: A numerical and experimental study

Alexandria Engineering Journal

Research paper thumbnail of Design Of Permanent Magnet Machines With Different Rotor Type

This paper presents design, analysis and comparison of the different rotor type permanent magnet ... more This paper presents design, analysis and comparison of the different rotor type permanent magnet machines. The presented machines are designed as having same geometrical dimensions and same materials for comparison. The main machine parameters of interior and exterior rotor type machines including eddy current effect, torque-speed characteristics and magnetic analysis are investigated using MAXWELL program. With this program, the components of the permanent magnet machines can be calculated with high accuracy. Six types of Permanent machines are compared with respect to their topology, size, magnetic field, air gap flux, voltage, torque, loss and efficiency. The analysis results demonstrate the effectiveness of the proposed machines design methodology. We believe that, this study will be a helpful resource in terms of examination and comparison of the basic structure and magnetic features of the PM (Permanent magnet) machines which have different rotor structure.

Research paper thumbnail of Permanent magnet synchronous motor design, production and experimental verification for compressor application

2016 National Conference on Electrical, Electronics and Biomedical Engineering (ELECO), 2016

In this study, 3 phase Permanent Magnet Synchronous Motor (PMSM) for refrigerator application was... more In this study, 3 phase Permanent Magnet Synchronous Motor (PMSM) for refrigerator application was designed and prototyped, experimental results carried out and validated. Design criteria was determined by taking into consideration constrains of the compressor. Proper slot/pole combination was identified and previously untested slot/pole combination was chosen as target. Speed® software was used for pre-design stage, optimization studies and detailed finite element analysis (FEA) was completed Maxwell® 3D software. The prototype of the motor was manufactured and motor performance was verified experimentally.

Research paper thumbnail of Electromagnetic and Thermal Analysis of a Domestic Induction Cooker Coil

2019 4th International Conference on Power Electronics and their Applications (ICPEA), 2019

In this study, induction cookers used in domestic applications are investigated. A commercially a... more In this study, induction cookers used in domestic applications are investigated. A commercially available induction cooker is chosen and a 3-dimensional finite element model of the cooker is investigated for electromagnetic analysis by using ANSYS electronics desktop. Magnetic flux density distribution of the bottom of the pan is also obtained. By using finite element method results, thermal analysis of the induction cooker is obtained by using ANSYS Fluent via ANSYS Workbench. Lastly, an experimental test was conducted to see the thermal characters of the induction cooker. The finite element method results are also compared with the experimental results.

Research paper thumbnail of Design of 75 kW asynchronous motor for electric vehicle applications

2016 National Conference on Electrical, Electronics and Biomedical Engineering (ELECO), 2016

In this study, the design of 75kW (continuous 50kW) squirrel cage induction motor for electric ve... more In this study, the design of 75kW (continuous 50kW) squirrel cage induction motor for electric vehicle applications is presented. First, the main design constraints and performance criteria are determined. Depending on these constraints and criteria, computer aided design of the motor is performed. Then, the electrical, magnetic and performance analyses of the motor are performed. The analysis results show that the designed motor satisfies the desired power specifications and the design performance criteria.

Research paper thumbnail of Investigating the Effect of Tap Insertion in Concentric Coil Transformer on the Electromagnetic Forces using Magnetostatic analysis

2020 International Conference on Electrical, Communication, and Computer Engineering (ICECCE), 2020

In the manufacturing of the concentric coil transformer, stability and working are mainly affecte... more In the manufacturing of the concentric coil transformer, stability and working are mainly affected by the insertion of the regulating tap in the transformer. The tap insertion can cause asymmetry on the transformer windings and increase the radial and axial forces. In this paper, a numerical approach is used to determine the electromagnetic forces in the concentric coil transformer with the different tap windings setup. Five different tapping configurations are investigated for the calculation of the electromagnetic forces. The classical and most commonly used analytical method is also compared with the numerical results of the first condition. Analytical results show a good agreement with the finite element method results. This work will be helpful to the transformer manufacturers and give great knowledge about the insertion of the tap in the concentric coil transformer.

Research paper thumbnail of Kendi Kendine Soğuyan Kuru Tip Güç Transformatörlerinde Sargı Isınma Hesabına Katkılar

Research paper thumbnail of Kendi Kendine Soğuyan Kuru Tip Güç Transformatörlerinde Sıcaklık Dağılımının Belirlenmesi

Yuksek gerilim sargisi yuksekligi 537,6.10-3 m olan, 13 bobinden meydana gelmis, dilimli, silindi... more Yuksek gerilim sargisi yuksekligi 537,6.10-3 m olan, 13 bobinden meydana gelmis, dilimli, silindirik sargili kendi kendine soguyan kuru tip bir guc transformatorunde Ansys sonlu elemanlar programi ile sicaklik dagilimi cikarilmistir. Alt, ust gerilim sargilari ve cekirdek ayri alinarak sargilar ve cekirdek arasindaki yag kanalinin sogutma etkisi de dikkate alinmistir. Akiskan ozelliklerinin sicaklikla degismesinden dolayi akiskan ve sicaklik beraber cozulmustur. Sargilar ve cekirdegin sicaklik dagilimlarinin yaninda bu parcalarin etrafinda bulunan havanin hareketi ve sicakligi da bulunmustur. En cok isinan noktanin yeri ve buyuklugu belirlenmistir. Yuksek gerilim sargi yuksekligi boyunca sicaklik dagilim egrisi cikartilmistir. Sicaklik dagilim egrisi deneysel calismayla elde edilen egriyle karsilastirilmistir. Anahtar Kelimeler: Transformator, sargi, sicak nokta sicakligi, sicaklik dagilimi, hiz dagilimi.

Research paper thumbnail of Design optimisation for distance between additional and tap winding in high‐voltage transformers

High Voltage, 2020

The transformer is one of the main components in the power network and transformer windings are o... more The transformer is one of the main components in the power network and transformer windings are one of the most expensive elements in the power transformer. Optimisation of winding distances is one of the most important parameters during the manufacturing of transformer. The distance between the windings in the two winding transformers is well known to transformer designers and manufacturers. However, insulation of the high voltage transformer with additional winding and tap winding is still a major problem for transformer designers. In this study, the additional winding to tap winding distance optimisation is made for a high voltage power transformer. Optimisation of the transformer's windings just not minimises the cost of the transformer but also increases the lifetime of the transformer. With additional winding and tap winding in high-voltage transformers, insulation distance is a major concern for minimising the cost and size of the high voltage transformer. In this study, an approach is made to balance the cost, size, and safety of high voltage transformers. The optimised distance and position between tap winding and additional winding are determined by using the finite element analysis. The finite element method results were also verified by making a prototype transformer.

Research paper thumbnail of Electromagnetic and Thermal Design/Analysis of an Induction Motor for Electric Vehicles

International Journal of Mechanical Engineering and Robotics Research, 2019

The most commonly used electrical machine is the induction machine since it is durable, easy to m... more The most commonly used electrical machine is the induction machine since it is durable, easy to manufacture and control. Additionally, it requires less maintenance, and responses different loads. In this study, the design of 115kW (continuous 85kW) squirrel cage induction motor is presented for electric vehicle applications. Main design constraints and performance criteria of the motor are determined and depending on these values, computer aided design is performed. In the design procedure, initially, an analytical design of the electric vehicle motor is performed depending on specified design criteria. Then, the analytical design is verified by using finite element analysis. Depending on the obtained results in electromagnetic analyses, the squirrel cage induction motor is modified in order to improve the obtained performance further. The electromagnetic and thermal analyses of the designed motor are performed by using Maxwell and ANSYS software programs, respectively. Designed motor will stand maximum allowable temperature based on temperature rise of the used insulation class. The analyses results show that the designed motor satisfies the design criteria.  Index Terms-Induction motor, electric vehicle, thermal analysis, electromagnetic analysis I.

Research paper thumbnail of Electromagnetic and Thermal Analysis/Design of an Induction Motor for Electric Vehicles

International Journal of Mechanical Engineering and Robotics Research, 2018

Induction machines are the most commonly used electrical machines in applications, since they are... more Induction machines are the most commonly used electrical machines in applications, since they are durable, easy to manufacture and control. Additionally, they require less maintenance and response different loads. In this study, the design of 115kW (continuous 85kW) squirrel cage induction motor is presented for electric vehicle applications. Main design constraints and performance criteria of the motor are determined, and the computer-aided design is performed depending on these values. In the design procedure, initially, an analytical design of the electric vehicle motor is performed depending on specified design criteria. Then, the analytical design is verified by using finite element analyses. Depending on the obtained results in electromagnetic analyses, the squirrel cage induction motor for electric vehicle is modified in order to improve the obtained performance further. The electromagnetic and thermal analyses of the designed motor are performed by using Maxwell and ANSYS software programs, respectively. The insulation class of the designed motor is determined by considering the maximum allowable temperature criterion. The analyses results show that the designed motor satisfies design constraints and performance criteria.

Research paper thumbnail of Investigation of winding MMF harmonic reduction methods in IPM machines equipped with FSCWs

International Transactions on Electrical Energy Systems, 2018

In this paper, implementation of fractional-slot concentrated windings (FSCWs) into an interior p... more In this paper, implementation of fractional-slot concentrated windings (FSCWs) into an interior permanent magnet (IPM) machine, designed by using the same geometrical and operational specifications as Toyota Prius 2010 IPM machine, has been presented. In detail, the Toyota Prius's IPM equipped with integer-slot distributed windings has been considered as a reference machine. Then the geometry of the stator has been adequately modified in other five models to equip FSCWs and adopt different magnetomotive force (MMF) reduction methods. It has been validated that the FSCW technique causes a significant increase in the rotor losses due to increase in the rate of the total harmonic distortion of the MMF harmonics. To reduce the effect of these harmonics, different MMF harmonic reduction methods including phase-winding coils with different number of turns, multilayer winding with phase shifting, and stator with flux barriers have been investigated. To reveal the effectiveness of the investigated MMF harmonic reduction methods, the key thermal and electromagnetic performance characteristics including torque, torque ripple, power losses, and efficiency have been numerically calculated by finite element method and have eventually been compared.

Research paper thumbnail of Application of Weibull Distribution Method for Aircraft Component Life Estimation in Civil Aviation Sector

Journal of Traffic and Logistics Engineering, 2017

The continuous monitoring of fleet reliability has been made compulsory by the aviation authoriti... more The continuous monitoring of fleet reliability has been made compulsory by the aviation authorities, due to the maintenance program for civil aviation aircrafts has been prepared on MSG-3 philosophy. In this context, task card and maintenance intervals must be set according to the reliability of aircraft components and systems. Approximately 90 percent of the maintenance programs prepared according to the MSG-3 philosophy contain task cards for finding defects or faults, and these do not have a relevant use in the absence of a defect or fault. In this study, reliability of the aircraft parts is estimated according to the Weibull distribution by using maintenance data, and the probability of failure for each part is calculated.  Index Terms-w eibull, w eibull analysis, civil avation, MSG-3, reliability analysis, life data analysis I.

Research paper thumbnail of Electrical design and testing of a 500 kW doubly fed induction generator for wind power applications

TURKISH JOURNAL OF ELECTRICAL ENGINEERING & COMPUTER SCIENCES, 2017

In this study, the electrical design and testing of a 500 kW doubly fed induction generator (DFIG... more In this study, the electrical design and testing of a 500 kW doubly fed induction generator (DFIG) is presented, developed in the context of the MILRES (Turkish National Wind Energy Systems) Project. The main objective of the MILRES Project is to encourage locally produced equipment for wind power systems. Therefore, in the DFIG design, the standard construction capabilities of the local machine manufacturers are especially taken into consideration. In this way, it is aimed that the designed DFIG can easily and cost-effectively be manufactured by local machine manufacturers in Turkey. In the DFIG design procedure, initially, an analytical design of the DFIG is performed depending on specified design criteria. Then the analytical design is verified by using finite element analysis. Depending on the obtained results in electromagnetic analyses, the DFIG design is modified in order to improve the obtained performance further. Finally, the designed DFIG is manufactured and its performance tests are performed at three different operating points. The test results verify the analyses results and show that the designed DFIG satisfies the desired performance criteria.

Research paper thumbnail of Influence of PV Penetration on Distribution Transformer Aging

Journal of Clean Energy Technologies, 2017

Increasing power demand urged countries to seek out energy sources with higher efficiency and low... more Increasing power demand urged countries to seek out energy sources with higher efficiency and lower cost than the existing ones. Solar energy is an effective alternative source to the traditional energy sources. The photovoltaic distributed generation is an effective energy source since it combines the advantages of smart grid and solar energy. Depending on the season, photovoltaic generation connected to the distribution network shows different penetration that affects the network load distribution, which can lead to excessive loading at lines, cables and transformers in distribution systems. As the life expectancy of transformers and cables in the distribution system depends on the operating conditions, overloading caused by penetration of distributed photovoltaic systems speeds up the aging of the components. Therefore, investigating the effects of photovoltaic systems on the aging is important for providing insight on the efficient use of components in the distribution transformers. In this study, the impact of loss of life on the distribution transformer photovoltaic production is examined by taking the seasonal influences into account from the point of view of a consumer.