Academic & Industry Positions

  • Present 2016

    Assistant Professor

    Okan University, Engineering Faculty

  • Present 2012

    Electrical Engineer

    Mekatro R&D Company, Mechatronic Systems Design

  • 2016 2011

    Research Assistant

    Okan University, Engineering Faculty

Education & Training

  • Ph.D. 2016

    Ph.D. in Mechatronics Engineering

    Okan University Graduate School of Engineering

  • B.A.2011

    Bachelor of Electrical Engineering

    Istanbul Technical University, Turkey

Research Projects

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    Advanced Charge Cable & Plug Development for Electric Vehicles Project

    TUBITAK 1507, Consultant, Beginning: 01/09/2018 Ending: 01/01/2020

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    Smart Advanced Autonomous Autobus Development Project

    TUBITAK 1505, Researcher, Beginning: 01/04/2018 Ending: 01/04/2020

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    Smart Home Energy Management System Based on Renewable Energy Source Design Project

    TUBITAK 1505, Researcher, Beginning: 01/11/2017 Ending: 01/11/2019

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    Industrial SEPIC Converter Design Project

    TUBITAK 1505, Researcher, Beginning: 01/11/2017 Ending: 01/11/2018

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    SynRM Driver & Parameter Estimation Algorithm Algorithm&Software Design

    Researcher, Mekatro R&D Comp.

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    Open Area Science Park Design

    Researcher, Mekatro R&D Comp.

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    Design and Implementation of High Maneuverability Autonomous Robot Platform for Industrial and Military Purposes

    TUBITAK 1002, Principle Investigator, Beginning: 01/12/2016 Ending: 01/012/2017

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    Very Low Speed Control of Three Phase AC Motor Using Least Mean Square Method With Low Resolution Encoder

    TUBITAK 1002, Researcher, Beginning: 01/11/2015 Ending: 31/10/2016

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    Intelligent and Connected Vehicle Technologies Development and Clustering Center

    ISTKA-TR10/15/YNK/0022-Beginning: 01/09/2015 Ending: 01/09/2016

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    Innovative and Sustainable Electric and Hybrid Electric Vehicle Technology Development and Clustering Center

    ISTKA-TR10/14/YEN/0088-Beginning: 01/09/2013 Ending: 01/09/2015

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    Implementation of Position Sensorless Direct-Drive Permanent Magnet Generator-based Small-Scale Wind Power Generating System for Wide Speed Ranges

    TUBITAK 3501, Researcher, Beginning: 01/04/2013 Ending: 01/01/2016

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    Design of a Position Controlled Electric Actuator Used in Fluid Control Valves Project

    Researcher, Mekatro R&D Comp.

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    Smart Pump Selection Algorithm Development Based on WEB Project

    Researcher, Mekatro R&D Comp.

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    UPS Control Software Development Project

    Researcher, Mekatro R&D Comp.

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    High Efficiency (IE4) LSIPMSM Design Project

    Researcher, Mekatro R&D Comp.

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    Design and Implementation of Electric Machine Driver

    KOSGEB, Researcher, Mekatro R&D Comp.

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    Design and Development of Electric Power Train for Solar Car Project

    Researcher, Mekatro R&D Comp.

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    Design and Implementation of E-Bike Power Train

    KOSGEB, Researcher, Mekatro R&D Comp.

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    Linear BLDC Motor and Driver Design for a Ramp System Project

    Researcher, Mekatro R&D Comp.

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    Development of Electric Power Train for Hub-Motor Electric Vehicle Project

    Researcher, Mekatro R&D Comp.

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A review of modular multilevel converters for stationary applications

Y. Wang, A. Aksoz, T. Geury, S.B. Ozturk, O.C. Kivanc, and O. Hegazy
Journal PaperApplied Sciences, vol. 10, no. 21, 7719, 2020.

Abstract

A modular multilevel converter (MMC) is an advanced voltage source converter applicable to a wide range of medium and high-voltage applications. It has competitive advantages such as quality output performance, high modularity, simple scalability, and low voltage and current rating demand for the power switches. Remarkable studies have been carried out regarding its topology, control, and operation. The main purpose of this review is to present the current state of the art of the MMC technology and to offer a better understanding of its operation and control for stationary applications. In this study, the MMC configuration is presented regarding its conventional and advanced submodule (SM) and overall topologies. The mathematical modeling, output voltage, and current control under different grid conditions, submodule balancing control, circulating current control, and modulation methods are discussed to provide the state of the MMC technology. The challenges linked to the MMC are associated with submodule balancing control, circulating current control, control complexity, and transient performance. Advanced nonlinear and predictable control strategies are expected to improve the MMC control and performance in comparison with conventional control methods. Finally, the power losses associated with the advanced wide bandgap (WBG) power devices (such as SiC, GaN) are explored by using different modulation schemes and switching frequencies. The results indicate that although the phase-shifted carrier-based pulse width modulation (PSC-PWM) has higher power losses, it outputs a better quality voltage with lower total harmonic distortion (THD) in comparison with phase-disposition pulse width modulation (PD-PWM) and sampled average modulation pulse width modulation (SAM-PWM). In addition, WBG switches such as silicon carbide (SiC) and gallium nitride (GaN) devices have lower power losses and higher efficiency, especially at high switching frequency in the MMC applications

A linear brushless direct current motor design approach for seismic shake tables

O. Ustun, O.C. Kivanc, and M.S. Mokukcu
Journal PaperApplied Sciences, vol. 10, no. 21, 7719, 2020.

Abstract

The progress in material and manufacturing technologies enables the emergence of new research areas in electromagnetic actuator applications. Permanent magnet (PM) linear motors are preferred to achieve precise position control and to meet the need for high dynamic forces in the seismic shake tables that are used in analyzing reactions of structure models. The design approaches on the linear motors used in the seismic shake tables may vary depending on the desired force, stroke and acceleration values. Especially, the maximum width, the maximum depth, the maximum linear motor length in longitudinal direction and the maximum travelling distance parameters are the primary design criteria in seismic shake table drive systems. In this paper, a design approach for a linear PM brushless direct current (BLDC) motor with high force/volume, force/weight and force/input power ratios is developed. The design was analyzed using two-dimensional (2D) and three-dimensional (3D) finite element method (FEM) approaches through the ANSYS Maxwell software. The mathematically designed linear BLDC motor was manufactured and subjected to displacement, acceleration and force tests that are used in seismic analyses. The results of the experimental tests validate the convenience of the proposed design approach and the selected parameters.

Rotor position alignment of FSTPI based PMSM drive using low frequency signal injection

S.B. Ozturk, O.C. Kivanc, A. Aksoz and O. Hegazy
Journal PaperApplied Sciences, vol. 10, no. 21, 7397, 2020.

Abstract

A PMSM drive with an incremental encoder or using sensorless control requires alignment to a predetermined rotor position (initial position) or initial rotor position detection at start-up. It is desired to lock the rotor to a known state (usually zero angle) at start-up if the initial rotor position detection is not available or difficult to obtain. In this work, a simple and proper zero angle initial rotor position alignment of four-switch three-phase (FSTP) inverter-based PMSM drive is proposed. Low-frequency voltage signal is applied to the d-axis voltage reference of the open-loop FSTPI based PMSM drive scheme without requiring complex trigonometric calculations, PI current regulators and current sensing. Therefore, fluctuated capacitor voltages at the DC-link are obtained allowing current flown through phase a locking the rotor with zero angle, properly. The proposed method has been implemented using a low-cost FSTP voltage source inverter (VSI) for PMSM drive with a floating-point TMS320F28335 DSP. The effectiveness and the feasibility of the proposed zero angle initial rotor position alignment method for PMSM driven by FSTP inverter have been demonstrated through experimental results.

High efficiency brushless direct current motor design for an unmanned ground vehicle

O.C. Kivanc
Journal PaperSuleyman Demirel University Journal of Natural and Applied Sciences, vol. 24, no. 2, pp. 494–501, 2020.

Abstract

Unmanned ground vehicles (UGV) offer different study areas to researchers due to their various modules. These modules can be included sensor technologies, embedded systems, mapping and localization, trajectory tracking, mechanical design, electric motor and battery technologies. Although electric motor technology from these research areas has reached more limit design values than the other areas mentioned, different design approaches are needed due to the complex and specific constraints of unmanned vehicles. In this study, a special outer rotor brushless direct current motor (BLDC) has been designed for UGV which has multi-axis movement, low friction and high vibration. Low speed, high torque and high efficiency in the design of a BLDC is restricted to space and volume can be easily manufactured. In the study, analytical solutions by ANSYS RMxprt, 2 and 3 dimensional analyzes are performed based on finite element method(FEA) using ANSYS Maxwell. The results obtained show the validity between the initial motivation and the design outputs and an electric motor which is producible, has been developed.

Design and analysis of 240-Watt SEPIC converter for LED applications

I. H. Hayirli, B. Kelleci, O.C. Kivanc, S. B. Ozturk, R. N. Tuncay and O. Citci
Conference Papersin Proc. IEEE ISIE, Vancouver, Canada, Jun. 12-14, 2019.

Abstract

A 240 Watt output power SEPIC converter with an output voltage of 24 V is proposed to be used in automotive and railway LED applications. The input voltage of the converter varies between 16 V and 36 V. The stability of the converter is guaranteed by moving one of the dominant pole to lower frequency and canceling the other pole with a zero. The phase margin is higher than 56° across all input voltage values. The transients of the switch is damped using a passive snubber circuit. Electromagnetic analyses are performed using Ansys SiWave™ to determine voltage drop, current distribution, near and far field and resonance behavior of SEPIC converter. Measurement results indicate that the SEPIC converter is stable under various operating conditions.

Optimal positioning of electric vehicle charging stations for a pilot region

Y.R. Sen, O.C. Kivanc and R.N. Tuncay
Conference Papersin Proc. International Symposium on Engineering Natural Sciences and Architecture, pp. 113–119, Kocaeli, Turkey, 2019.

Abstract

The use of electric vehicles as an alternative source in the transportation has led to an increase in charging demand. In parallel to the widespread use of these vehicles, which are both superior in performance and emissions, the need for the appropriate infrastructure should be increased. Due to this infrastructure requirement, the positioning of the charging stations, and their effect on the grid have become an important research area. The proper positioning of the charging stations with respect to user profiles and charging times, minimizes the adverse effects on the existing grid network and also reduces the investment cost. In this study, a real-time distribution model has been developed by providing information about the transformer and cables on the distribution system in a pilot area in Istanbul, selected in the European Side, with a six-month usage data. Real-time data has been recorded using the SQL database and used in the analysis. Three different -scenarios have been created by considering the positions of the transformer centers. These scenarios are listed as university region, shopping center, and residential area. In the scenarios created, the load demand for the various times of the day has been obtained for these areas. The usage habits, routes and travel times have been obtained with Global Positioning System (GPS). In the scenarios, different loads are defined at various times in the transformer centers of the feeder, and the optimum positioning analysis has been performed by using the CYME power system modeling software. In the analysis, the losses in the grid, voltage drops, overloading of cables, overloading of the transformer centers are calculated for standard charging and fast charging options. For the selected pilot region, the positioning of the charging stations at 7.4 kW, 22 kW, 43 kW powers are distributed to 11 separate substations and optimized scenario is created. As a result of the developed models and analyses, a positioning map has been obtain

Design and implementation of an electric actuated valve for precise fluid control

O.C. Kivanc, O. Ustun, G. Tosun, E. Oguz and Y. Mutlu
Journal PaperGazi University Journal of Science, 32(2), 483–492, 2019.

Abstract

Fluid control is one of the essential automation application area in industry. In order to fluid control effectively and precisely, valves which are crucial components, need a controlled rotating motion which leads to implement electric motors, electronic controller and gear systems altogether. In this study, an electric motor actuated valve system is designed and prototyped. The design phases are including switch mode power supply (SMPS) design, motor controller circuit design, mechanical implementation and controller design. The designed valve system is manufactured and tested using multi-disciplinary fashion. The application problems are solved by using the proper control techniques and strategies. The precise position control of butterfly disc is also achieved. According to the related industrial standard and application requirements, the experimental results show the effectiveness of the design approach.

Investigation of the effects of physical changes on li-ion battery

O.C. Kivanc
Journal PaperEuropean Journal of Science and Technology, 16(2), 235-241, 2019.

Abstract

With the advances in battery technologies, the li-ion battery’s amount of energy storage per unit volume and weight increases and significant improvements occur in their control systems. Besides, the usage rate of li-ion batteries increases due to the decrease in prices of li-ion batteries in many areas from electric vehicles to user electronics. However, for high-performance use of these batteries, continuous monitor and control of their states of health and charge are needed. This control is commonly performed by using the voltage, current and temperature of the cells. In contrast, swelling and physical deformations of the cells should be used as function inputs in the monitoring of the state of safety condition. Especially for devices such as mobile phones and portable computers which directly touch to person, causes serious safety problems. In addition, the user's various usage habits which are using different battery chargers, fast charging and using in the charging process, lead to safety problems. In addition, in the electric vehicles, the series/parallel packaged cells swell and thus increase the pressure on the neighboring cells. In this study, a system with a high precision strain gauge, temperature sensor and Z-Wave communication module has been designed to observe the effects of strain changes and to investigate their effects. Aging tests have been performed on one single battery used in the market and a 4.58 mm swelling has been achieved. The behavior of the new battery and aged battery which has physical deformation is applied to the same charge/discharge cycles and the effects of the swelling are presented. Measurements of temperature, swelling amount, open circuit voltage and charge/discharge time of the amount of change are stated in detail. It has been shown that dangers occur for the user due to the high temperatures on the surface caused by the amount of swelling of the battery exposed to swelling during charge and discharge. This situation reveals the necessity of continuous monitoring of the swelling as a safety factor in mobile phones and portable computers.

Dynamic control of electronic differential in the field weakening region

O.C. Kivanc and O. Ustun
Journal PaperInternational Journal of Electronics, 106(10), 1583-1601, 2019.

Abstract

A simple and dynamic electronic differential control method for an outer rotor motor driven electric vehicle based on fuzzy gain scheduling of PI gains method is proposed for constant torque and power region operation using brushless direct current (BLDC) machine. The proposed method is quite insensitive to torque fluctuations and transient speed oscillations due to surface mounted permanent magnet (SMPM) BLDC machines constraints in the field weakening region. To improve the dynamics and stability of the electronic differential system and eliminate the skidding of the wheels and reduce the heating of electric machine in the wide speed range operation, a robust control method is developed. Moreover, PI controller gains are updated continuously by fuzzy gain scheduling approach which has phase advance angle, steering angle and measured speed as controller input parameters in order to eliminate the errors caused from the variable road conditions and torque oscillations in the field weakening region. The proposed method is implemented with 2 × 1.5 kW BLDC motor drive controlled by a TMS320F28335 digital signal processor (DSP). The experimental results show that the proposed method exhibits greater stability under various load, road and vehicle speed conditions.

An approach to improve the performance of cooperative unmanned vehicle team

O.C. Kivanc
Journal PaperTURKISH JOURNAL OF ELECTRICAL ENGINEERING & COMPUTER SCIENCES, 27(2), 1428-1444, 2019.

Abstract

In this paper, a method based on optimal energy management is proposed in order to improve the operational and tactical abilities of collaborative unmanned vehicle teams. Collaborative unmanned systems are used in surveillance, tracking, and military operations. The optimal assignment of these tasks requires cooperation among the vehicles in order to generate a strategy that is efficient with respect to overall mission duration and satisfies all problem constraints. The key motivation behind this paper is to design an unmanned vehicle team that mitigates the disadvantages caused by the structures and characteristics of unmanned ground vehicles (UGVs) and unmanned aerial vehicles (UAVs), which are used in these systems. The design steps of the developed system are explained in three sections in a multidisciplinary fashion. In the first section, the optimal energy consumption profile is estimated by simulating the UAV's flight on a Nvidia Jetson TX2 embedded system, located on the UGV. In the second section, a UAV charger design and implementation is done via development of a TMS320F28335 DSP controlled 65 W inductive wireless power transfer circuit, and in the third section an algorithm that calculates the optimal range and route for the user-selected way points using the state of charge of the UAV's LiPo batteries and a preflight simulation using the simulated annealing method are developed. The experiments are performed in real time with an example scenario and the proposed strategy's suitability and effectiveness are verified for cooperative unmanned vehicle teams.

Low-Cost Position Sensorless Speed Control of PMSM Drive Using Four-Switch Inverter

O.C. Kivanc and S.B. Ozturk
Journal PaperEnergies, 12(4), 741, 2019.

Abstract

A low-cost position sensorless speed control method for permanent magnet synchronous motors (PMSMs) is proposed using a space vector PWM based four-switch three-phase (FSTP) inverter. The stator feedforward d q-axes voltages are obtained for the position sensorless PMSM drive. The q-axis current controller output with a first order low-pass filter formulates the rotor speed estimation algorithm in a closed-loop fashion similar to PLL (Phase Lock Loop) and the output of the d-axis current controller acts as the derivative representation in the stator feedforward voltage equation. The proposed method is quite insensitive to multiple simultaneous parameter variations such as rotor flux linkage and stator resistance due to the dynamic effects of the PI current regulator outputs that are used in the stator feedforward voltages with a proper value of K gain in the q-axis stator voltage equation. The feasibility and effectiveness of the proposed position sensorless speed control scheme for the PMSM drive using an FSTP inverter are verified by simulation and experimental studies.

An integrated approach to development of unmanned ground vehicle: design, analysis, implementation and suggestions

O.C. Kivanc, T.E. Mungan, B. Atila and G. Tosun
Journal PaperJournal of The Faculty of Engineering and Architecture of Gazi University, 34(4), 1957-1973, 2019.

Abstract

As the intelligent vehicle concept accelerated with electric vehicles, and then interest in autonomous vehicle technologies increased, investments on unmanned ground vehicle (UGV) studies also accelerated. Unmanned ground vehicles, despite their complex structure and technology, bring many advantages with their use. The most important advantages of UGVs are that they do not have human-specific features (sleepiness, fatigue, anger, etc.), react faster, and reach a decision by calculating possibilities according to the conditions. In this study, a UGV has been developed, which has the ability to navigate to a self-determined or unknown area, ability of mapping, localization, trajectory detection and tracking, detection of obstacles and finding a new path to avoid collisions with these obstacles. In an area without a specific map, skecth or floor plan, UGV's autonomous driving capability in indoor and outdoor, has been verified by the experiments. The phases, problems, solution techniques and results required for UGV design are presented with a systematic approach in this study.

On Field Weakening Performance of a Brushless Direct Current Motor with Higher Winding Inductance: Why Does Design Matter?

O. Ustun, O.C. Kivanc, S. Senol and B. Fincan
Journal PaperEnergies, 11(11), 3119, 2018.

Abstract

This paper comprises the design, analysis, experimental verification and field weakening performance study of a brushless direct current (BLDC) motor for a light electric vehicle. The main objective is to design a BLDC motor having a higher value d-axis inductance, which implies an improved performance of field weakening and a higher constant power speed ratio (CPSR) operation. Field weakening operation of surface-mounted permanent magnet (SMPM) BLDC motors requires a large d-axis inductance, which is characteristically low for those motors due to large air gap and PM features. The design phases of the sub-fractional slot-concentrated winding structure with unequal tooth widths include the motivation and the computer aided study which is based on Finite Element Analysis using ANSYS Maxwell. A 24/20 slot–pole SMPM BLDC motor is chosen for prototyping. The designed motor is manufactured and performed at different phase-advanced currents in the field weakening region controlled by a TMS320F28335 digital signal processor. As a result of the experimental work, the feasibility and effectiveness of field weakening for BLDC motors are discussed thoroughly and the contribution of higher winding inductance is verified.

Sensorless PMSM Drive Based on Stator Feedforward Voltage Estimation Improved With MRAS Multi-Parameter Estimation

O.C. Kivanc and S.B. Ozturk
Journal PaperIEEE/ASME Transactions on Mechatronics, 23(3), 1326-1337, 2018.

Abstract

In order to reduce the adverse effect of parameter variation in position sensorless speed control of permanent magnet synchronous motor (PMSM) based on stator feedforward voltage estimation (FFVE), multi-parameter estimation using model reference adaptive system (MRAS) is proposed. Since the FFVE scheme relies on motor parameters, the stator resistance and rotor flux linkage are estimated and continuously updated in the feedforward voltage estimation model in a closed-loop fashion, sensitivity to multi-parameter changes at low speed is eliminated. To improve the dynamics and stability of the overall system and eliminate transient oscillations in speed estimation, a PLL-like speed estimation method is proposed which is obtained by passing the q-axis PI current regulator output through a first order filter in the FFVE scheme. The proposed control method is similar to V/f control as in induction motors, therefore starting from zero speed is possible. The experimental tests are implemented with 1 kW PMSM drive controlled by a TMS320F28335 DSP. The proposed sensorless scheme is also compared with the classical Sliding Mode Observer (SMO). Experimental results show that the proposed sensorless scheme exhibits greater stability at lower speed than the classical SMO under parameter detuning. Experimental results and stability analysis demonstrate the feasibility and effectiveness of the proposed sensorless scheme for PMSM under various load and speed conditions.

Sensorless control of PMSG drive using reduced switch inverter

O.C. Kivanc and S.B. Ozturk
Journal PaperPamukkale University Journal of Engineering Sciences, 25(2), 132-142, 2019.

Abstract

The main aim of this paper is to provide electric power generation using a renewable and portable method in rural and geographically problematic areas where energy transmission is not possible. Electric power generation from wind with low-cost, efficient and portable small-scale wind turbine during natural disasters (earthquake, fire, flood, etc.) leading to catastrophic consequences (long electrical black-outs) and for individual low power applications is targeted. The control of gearless Permanent Magnet Synchronous Generator (PMSG) along with load side inverter control in this project are performed using a full-rating, bi-directional, two-level, back-to-back voltage source rectifier/inverter with total of 8 switches for the variable speed wind turbine. Therefore, one of the major advantages and novelty of using MRAS rotor flux linkage and stator resistance estimator in this system is to correct changes in the flux and stator resistance values in the control system. Due to its simplicity and effectiveness, the load side control is achieved by using four switch grid side inverter. To observe the total system performance, a three-phase passive load is used at the inverter output. The low-pass LCL filter is designed and used in the load side to reduce current and voltage harmonics and increase stability and efficiency of the power network. The results of the overall system are validated with the real-time DSP system. It is proved with this paper that the inclusion of a simple, effective and economical position sensorless control in the generator side show that renewable wind energy system can be a viable distributed green energy solution for rural areas.

Stator Feedforward Voltage Estimation Based Sensorless Permanent Magnet Synchronous Generator Drive Using Multi-Parameter Estimation Based on MRAS

O.C. Kivanc and S.B. Ozturk
Journal PaperÇukurova Üniversitesi Mühendislik-Mimarlık Fakültesi Dergisi, vol. 32, no. 3, 2017, pp. 227-242.

Abstract

A simple and efficient position sensorless control method based on feedforward voltage estimation for PMSG improved with multi-parameter estimation using MRAS is proposed in this paper. The dynamically enhanced stator feedforward dq‒axes voltages that are derived from steady-state PMSG model are modified for the sensorless drive. In direct-drive wind turbine systems, because of low backEMF amplitude in the generator output at very low speed operation, the rotor flux linkage cannot be predicted correctly. Vector control is often used in PMSG control, because it has a simple structure and is suitable for various industrial systems. In the power equation, maximum power is obtained as a function of torque and speed. In the proposed method, a variable-speed wind turbine system with back to back converter structure is connected to common DC-link. In this paper, the proposed sensorless control scheme has been implemented with 1 kW PMSG drive controlled by a TMS320F28335 DSP for low speed at 0.1 p.u. (300 rpm) is achieved under multi-parameter variations.

An integrated approach to development of electric vehicle powertrain: design, analysis and implementation

O. Ustun, R.N. Tuncay, M.S. Mokukcu, O.C. Kivanc, G. Tosun, C. Gokce and M. Cakan
Journal PaperTurk J Elec Eng & Comp Sci, 26, 2018, pp. 1541-1554

Abstract

Electric motor and power electronic systems are the essential elements for the performance and efficiency of electric vehicles (EVs) and hybrid electric vehicles (HEVs). Inadequacy of the range due to the battery limitations is compensated by powertrain solutions and innovative control algorithms. Future targets of electric powertrains are mostly based on weight, space and efficiency issues. High-efficient, low volume and light weight propulsion systems increase the performance of EVs and also enhance the importance of being alternative to internal combustion engine vehicles (ICEVs). In this paper, a detailed propulsion system design study is presented by considering all important constraints of electric powertrain. The design criteria and output which are alternative to each other are submitted in respect to advantages and disadvantages. The tests of all constraints are conducted as a whole and discretely, then the effects of electrical machine and power electronics circuit are presented in this paper.

Parametrical method of low-frequency harmonics supression in rectifier's output voltage under supply voltage unbalances: mathematical model, study and industrial applications)

P.G. Ali Zada, R.N. Tuncay, S.B. Ozturk, O.C. Kivanc, H.A. Mamedov and S.A. Abdullaev
Journal Paper Scientific Journal of Mathematical & Computer Modelling, vol. 13, 2017.

Abstract

This paper deals with using an original and pure electronic method for low-frequency harmonic suppression with wide industrial realization and application, in place of the usually heavy inductive, low-frequency harmonic filters. One of the main applications was made for small land power supply units of onboard complexes in ground-based air navigation when preflight ground check-service is made. The transport management at thousands of small provincial airports in the former country is still unfortunate. The same situation is in Northern and central Central Asia, Northern Caucasian and Trans-Caucasian Mountains, oriented to small civil and agricultural services airports, etc. Everywhere the phase and line voltage amplitude unbalance can reach between 10-15% at the settlement’s power tiny transformer or generator and there are thousands and thousands of such local «airports» [1, 6]. This paper has been editing by a native speaker, Ms. Rachel Alcorn — our sincere thanks.

Sector determination for SVPWM based four-switch three phase voltage source inverter

O.C. Kivanc and S.B. Ozturk
Journal Paper IET Journal of Electronics Letters, vol.53, no.5, pp. 343-345, 2017.

Abstract

Sector determination for a normalized space vector pulse width modulation (SVPWM) scheme is proposed for four-switch three phase (FSTP) voltage source inverter (VSI) by using already available stationary reference frame stator voltages without requiring complex trigonometric calculations. The proposed method has been simulated by using MATLAB/Simulink and implemented using a voltage source inverter with a TMS320F28335 floating-point DSP. Simulation and experimental results show the feasibility and effectiveness of the proposed SVPWM algorithm for FSTP inverter.

Matlab Function Based Approach to FOC of PMSM Drive

O.C. Kivanc and S.B. Ozturk
Journal Paper International Journal of Simulation Systems, Science & Technology, vol. 17, no. 33, 2016

Abstract

In this study, modeling and simulation of a speed sensored field-oriented control (FOC) of a permanent magnet synchronous motor (PMSM) drive is developed by using MATLAB Function blocks in MATLAB/Simulink. This method allows easier algorithm and software development stages for experimental studies compared to the classical block diagram approach. The superiority of the method over commonly used "Code Generation" tools is also emphasized. First, a MATLAB/Simulink model of the FOC of PMSM drive is developed by using MATLAB programming in MATLAB Functions similar to C coding techniques. The results of the simulation are presented. Then, the MATLAB programming based codes developed in simulation are implemented in a TMS320F28335 floating-point MCU by using C programming language and the experimental results are obtained. Finally, the results of the simulation and experiments are compared.

High performance position control of double sided air core linear brushless DC motor

P. Norouzi, O. Ustun and O. C. Kivanc
Conference PapersElectrical and Electronics Engineering (ELECO), 2017 10th International Conference on, 2017, Bursa, Turkey.

Abstract

Double-Sided Air Core Linear Brushless DC motors widely used in the industry where longitude motion is needed. In terms of efficiency, high speed and acceleration, long life, Stiffness, few moving parts, precise positioning and no transmission components, and so on have many advantages. In this paper position control of a Double Sided Air Core Linear BLDC motor is studied by two methods, first of all the classical PID control method is applied to the system and then Fuzzy-PID control method is investigated on system. The motor specifications and technical features of it are derived and presented. The simulation and the motor model including the control algorithm is built by using of Simulink and is investigated. Finally, to validate simulation result, designed controllers are applied to the Double-Sided Air Core Linear Brushless DC Motor practically. The experimental test results validate simulation result and the accuracy of the both control method and their dynamic performances are compared with each other.

Study on Development of Line Start IPM Synchronous Motor for Super Premium Efficiency Class

D. Bayram, O. Ustun, B. Durak, H. Gedik and O. C. Kivanc
Conference Papers18th International Symposium on Applied Electromagnetics and Mechanics (ISEM) 2017, Chamonix/France, 3, September, 2017.

Abstract

Recently, the increasing requirements and tendencies of higher efficiency systems have caused a substantial impact on electric motor design. Designers tend to change their views on motor topologies to provide the predetermined values of higher efficiency classes (such as IE3, IE4, IE5). Line-start interior permanent magnet synchronous motors (LSIPMSM) are strong candidates for higher efficiency class general purpose motors due to their higher MTPA (maximum torque per ampere) values. In this study, three different rotor types of LSIPMSM, i.e. V-magnet type, spoke-magnet type and rectangular-magnet type, are investigated with regard to efficiency requirements of super premium efficiency class (IE4). The impact of designs on rotor cage which is essential for starting and synchronization is also studied. The electromagnetic design study is conducted and then the optimized designs are manufactured and tested. The most applicable motor type is determined by means of its ease-of-manufacture and low cost features.

Comparison of different line start interior permanent magnet synchronous motor types with respect to IE4 efficiency class

O. Ustun, D. Bayram, B. Durak and O. C. Kivanc
Conference PapersElectromagnetic Fields in Mechatronics, Electrical and Electronic Engineering (ISEF) Book of Abstracts, 2017 18th International Symposium on, pp. 1–2, 2017, Lodz, Poland.

Abstract

Recently, the increasing requirements and tendencies of higher efficiency systems have caused a substantial impact on electric motor design. Designers tend to change their views on motor topologies to provide the predetermined values of higher efficiency classes (such as IE3, IE4, IE5). Line-start interior permanent magnet synchronous motors (LSIPMSM) are strong candidates for higher efficiency class general purpose motors due to their higher MTPA (maximum torque per ampere) values. In this study, three different rotor types of LSIPMSM, i.e. V-magnet type, spoke-magnet type and rectangular-magnet type, are investigated with regard to efficiency requirements of super premium efficiency class (IE4). The impact of designs on rotor cage which is essential for starting and synchronization is also studied. The electromagnetic design study is conducted and then the optimized designs are manufactured and tested. The most applicable motor type is determined by means of its ease-of-manufacture and low cost features.

A simple least squares approach for low speed performance analyis of indirect FOC induction motor drive using low-resolution position sensor

S. B. Ozturk, O. C. Kivanc, B. Atila, S. U. Rehman, B. Akin and H. A. Toliyat
Conference Papers IEEE International Electric Machines and Drives Conference (IEMDC), pp. 1–8, 2016, Miami, USA.

Abstract

This paper investigates an ordinary least squares based indirect field oriented control (IFOC) of induction motor at very low speed range (1-5 rpm) using a low-count encoder. At very low speeds the speed estimation provided by common techniques for low-count encoder applications such as averaging the last two speed samples and/or considering the previous speed value until the next position update can generate erroneous speed results which can cause instability in the overall control system. By proposing ordinary least squares (OLS) method with low-resolution position sensor based speed estimation for IFOC of IM drives more realistic speed can be obtained by fitting the predefined sets of speed data in a linear or quadratic manner. Experimental tests prove that the proposed scheme which is constituted of OLS (linear) speed estimation algorithm increases stability and improves low and oscillating speed performance of IFOC of IM drive with low-count encoders down to four pulses per revolution.

Electro-hydraulic power steering system modelling for parameter fault detection based on model reference adaptive frame

O. C. Kivanc, S. B. Ozturk, R. N. Tuncay, E. Kesici and C. Yazi
Conference Papers Industrial Electronics Society , IECON 2016 - 42nd Annual Conference of the IEEE, 23-26 Oct. 2016, Page(s):1808 - 1814

Abstract

A simple and efficient fault detection and parameter monitoring algorithm for electro-hydraulic power steering (EHPS) system is proposed using model reference adaptive system (MRAS) without any additional sensor. In a faulty situation where the hydraulic system is disabled, assisted power is provided by an electric motor. Therefore, in low speed maneuvers, during sudden direction changes and parking, some parameters of an electric motor in EHPS are affected. These changes threaten the vehicle's driving reliability and performance of EHPS. In this study, an EHPS system with rotor flux estimation based adaptive driver torque control principle has been presented. The motor winding temperature is obtained for monitoring purpose with the help of MRAS stator resistance estimation. The proposed parameter estimation method for EHPS has been simulated by using AMESim and MATLAB/Simulink cosimulation model. Simulation results demonstrate the feasibility and effectiveness of the proposed method.

On regenerative braking capability of BLDC motor

O. C. Kivanc, O. Ustun, G. Tosun, R. N. Tuncay
Conference Papers Industrial Electronics Society , IECON 2016 - 42nd Annual Conference of the IEEE, 23-26 Oct. 2016, Page(s):1710 - 1715

Abstract

The solution for range problems in electric vehicles is implying two essential approaches: consuming electrical energy with maximised efficiency and regenerative braking. Regenerative braking can be implemented by using the any converter used for electric motor control without needing an extra power circuit. To accomplish recovering electrical energy from mechanical energy a voltage boosting operation is necessary which is causing the current flow from induced voltage due to the mechanical motion to battery. In this study, a brushless DC (BLDC) motor drive system used for light electric vehicle propulsion is modeled by considering non-linear effects. The developed model of the motor drive system is used for defining the upper limits and constraints of operation. Analytic calculations and simulation results represent the operation modes of the system when regenerative braking is applied.

Design of a position controlled electric actuator used in fluid control valves

Gurkan Tosun, O. Cihan Kivanc, Ender Oguz, Yasar Mutlu, Ozgur Ustun
Conference Papers Power Electronics and Motion Control Conference (PEMC), 2016 IEEE International, 25-28 Sept. 2016, Pages: 551 - 556

Abstract

Valves are the main elements for controlling fluids in industry and other application areas. To control flow precisely, valves need a controlled action which leads to implement actuators, gear systems and electronic controllers. Increasing dominance of electrical actuators due to the advantages of easy control and intervention and space-efficient designs brings seldom implementation of hydraulic and pneumatic actuation. In fluid control applications, the main target is to obtain the right position, i.e. angle for rotary actuators, for adjusting flow rate. In this study, the design and implementation of a position controlled electrically actuated valve used for fluid control are presented. The design phases of system universal power supply and electronic control system are given and the experimental results of position control which are representing the validation the design study is also discussed. Also a special current control scheme is used to overcome transient disruptions.

In pursuit of proper BLDC motor design for electric bicycles

O. Ustun, G. Tanc, O. C. Kivanc, G. Tosun
Conference Papers Electrical Machines (ICEM), 2016 XXII International Conference on, 4-7 Sept. 2016, Pages: 1808 - 1814

Abstract

In this paper, an electric bicycle motor design study is presented according to the related standard. Fundamental dimensions and characteristics are kept within some certain boundaries by means of motor rated power and physical constraints arising from standard bicycle sizes available on the market. Slot/pole ratios and winding configurations are investigated comprehensively in order to obtain a proper design of electric motor due to the facts of pedal assisted electric bicycle application. After defining the motor parameters and the materials that are used the motor design an optimisation attempts are undertaken by using an analytical solver which is employing both numerical calculations and finite element method (FEM) analyses. Motor designs are assessed based on torque production, weigh, efficiency and ease-of-manufacture. A concise experimental study is conducted for prototype motor in order to evaluate validity of design study.

Iyilestirilmis RANSAC Tabanli Isaret Cikarimi Algoritması Gelistirilmesi

Berkin Atila, Tahir Eren Mungan, Ömer Cihan Kıvanç
Conference Papers Türkiye Robotbilim Konferansı, 2016, 2-3 Kasım. 2016

Abstract

Yapılan çalışmada insansız kara araçları için iç mekân konumlandırılmasında kullanılmak üzere iyileştirilmiş RANSAC algoritması geliştirilmiştir. Önerilen algoritma, klasik RANSAC algoritmasından farklı olarak belirli bir eşik değerin üstündeki doğruyu rastgele aramak yerine belirli bir eşik değerin üstündeki bütün doğruların tespit edilmesi ve en iyisinin seçilmesi üzerine kurgulanmıştır. Önerilen algoritmanın performansı test sonuçları ile desteklenerek gösterilmiştir.

Different filter approaches and performance analysis of fundamental sensors in autonomous ground vehicles

Berkin Atila, Tahir Eren Mungan, Ömer Cihan Kıvanç
Conference Papers Signal Processing and Communication Application Conference (SIU), 2016 24th, 16-19 May 2016, Pages: 1605 - 1608

Abstract

Autonomous ground vehicles are being designed and produced for industrial or military purposes. Since most of these vehicles are high cost the sensors used are high sensitive. However, sensors used in low cost robotic applications have low resolution. When non-precision sensor data added to measurement errors caused by different typical of geometry and drive methods, process functions of robots are hitching. To prevent this, five simple-structured filters are designed and compared in this study for low cost distance sensors and GPS sensors data. It has been observed that accuracy of hybrid-structured filters are more suitable than mono-structured filters in the results obtained.

Development of high efficiency multi-output flyback converter for industrial applications

Gurkan Tosun, Omer Cihan Kivanc, Ender Oguz, Ozgur Ustun, R. Nejat Tuncay
Conference Papers 2015 9th International Conference on Electrical and Electronics Engineering (ELECO), 26-28 Nov. 2015, Pages: 1102 - 1108

Abstract

This study presents the development processes of a high-efficiency two-output flyback-converter. The detailed design phases are presented together with encountered design obstacles, limitations and the methods to overcome them. Despite their widely use in industry, studies on high-efficient flyback converter design still remains a need. Most of the flyback converters are designed with multi outputs for their various input voltages. This study firstly describes the preliminary design stages, modeling studies and definition of magnetic and electronic components and PCB design processes followed by a prototype manufacturing. Modelling study is conducted in MATLAB/Simulink environment, and PCB design is realized in Altium Designer Software. Prototype is tested and its performance parameters are recorded. It is seen that the performance values are good agreement with those of design objectives.

MATLAB Function Based Approach to FOC of PMSM Drive

Omer Cihan Kivanc, Salih Baris Ozturk
Conference Papers Modelling Symposium (EMS), 2015 IEEE European, 6-8 Oct. 2015, Pages: 96 - 102

Abstract

In this study, modeling and simulation of a speed sensored field-oriented control (FOC) of a permanent magnet synchronous motor (PMSM) drive is developed by using MATLAB Function blocks in MATLAB/Simulink. This method allows easier algorithm and software development stages for experimental studies compared to the classical block diagram approach. The superiority of the method over commonly used "Code Generation" tools is also emphasized. First, a MATLAB/Simulink model of the FOC of PMSM drive is developed by using MATLAB programming in MATLAB Functions similar to C coding techniques. The results of the simulation are presented. Then, the MATLAB programming based codes developed in simulation are implemented in a TMS320F28335 floating-point MCU by using C programming language and the experimental results are obtained. Finally, the results of the simulation and experiments are compared.

Development and implementation of field weakening algorithm for brushless DC motors

O. Ustun, R. N. Tuncay, O. C. Kivanc, B. Fincan and G. Tosun
Conference Papers Eleco 2014 Electric – Electronic – Computer and Biomedical Engineering Congress, 27 – 29 Nov 2014, Pages: 183 - 187

Abstract

There are some limitations on the field weakening operation of surface magnet mounted brushless dc motors. The main reason of this problem that surface magnet mounted BLDC motors have equal direct and quadrature axis inductance values. And due to the lower permeability of permanent magnet materials, they have lower winding inductances which cause higher characteristic currents. In this study, a phase advanced current method for field weakening operation is implemented for a specially designed subfractional slot concentrated winding BLDC motor with higher winding inductance. An algorithm is designed for the phase advanced current method and the results are verified experimentally.

Istanbul Technical University Full Electric Vehicle Project-ITU EV

Özgür Üstün, R.N. Tuncay, Mert Safa Mökükcü, Ömer Cihan Kıvanç, Gürkan Tosun
Conference Papers OTEKON 2014, 7. Otomotiv Teknolojileri Kongresi, 26 - 27 Mayıs 2014

Abstract

In recent years all expositions of cars show that every OEM is developing at least one electric vehicle. This subject is growing because of petrol reserve limitation, advertisements of new technology, which grows more interest, and high efficiency of electric vehicles. From these ideas, Istanbul Technical University Alternative Energy Club members and it’s supervisor created an electric vehicle project called ITU EV. This project is about developing a drive system for a conventional ICE vehicle. ITU EV project is funded by Istanbul Technical University by every means. It’s designers are ITU students and ALEK supervisors. Starting year of the project is 2011. Project has four different main research areas. These are electric powertrain, battery part, controlling part and mechanical construction and outer design part. In this study, electric powertrain design, vehicle user interface and production parts of the project will be investigated. For electric drivetrain a special design 70 kW powered BLDC motor is produced and laboratory tests are made. The rated voltage is chosen as 355 V. For transmission output power of the motor shaft, vehicle’s original transmission system will be used. For driving motor, an inverter design and assembly is made. The designed motor’s power need calculations are made by hand and design is made by computer aided softwares. For infotaintment a special vehicle user interface is created. In-vehicle communication is provided by CAN communication protocol. Data are processed on Matlab which is working in background and reflected into driver control panel.

Design and manufacture of electric powertrain and its cooling system for ITU EV project

O. Ustun, M. Cakan, R. N. Tuncay, M. S. Mokukcu, O. C. Kivanc, Y. Mutlu, G. Tosun
Conference Papers Electrical Machines (ICEM), 2014 International Conference on, 2-5 Sept. 2014, Pages: 730 - 735

Abstract

In recent years all expositions of cars show that every car manufacturing company is developing at least one electric vehicle. Recently, ITU ALEK (Istanbul Technical University Alternative Energy Club) members and its supervisor created an electric vehicle project called ITU EV (electric vehicle). This project is about developing a drive system for a conventional internal combustion engine (ICE) vehicle. The project which started in 2011, has four different main research areas. These are electric powertrain which includes water cooling design, battery part, controlling part, mechanical construction and outer design part. In this study, electric powertrain design, cooling calculations and design, and production parts of the project will be investigated. For electric drivetrain a special design of 70 kW BLDC (brushless dc) motor is produced and laboratory tests are made. The rated voltage is chosen as 355 V.

Exciting system selection for brushless synchronous machine

O. Ustun, S. B. Ozturk, O. C. Kivanc, P. G. Ali Zade, R. N. Tuncay
Conference Papers Power Generation, Transmission, Distribution and Energy Conversion (MEDPOWER 2012), 8th Mediterranean Conference on, 1-3 Oct. 2012, Pages: 1 - 6

Abstract

The paper deals with the special brushless synchronous electrical machine (SBSM) working with an extensive variable load. It's exciting systems usually keep cosφ ≈ 1. Among them are unmanned deep-well oil pumps drives, wind renewable energy SBSM, etc. The SBSMs usually works in harsh climate conditions, where thyristor or IGBT exciting systems are not reliable (except diodes). Oil field drives are supposed to have fire/explosion-proof brushless motors. It is shown in this paper that replacement of induction motors (IMs) with the special brushless synchronous motors (SBSM) with stable cosφ ≈ 1 in the sucker-rod pumps (SRPs) will help to cut energy losses and diminish voltage pulsations in the oil field electric network. It also results in some reduction of oversize motor utilizations. The main proposal of this paper is to avoid any controlled electronic exciting system, but at the same time obtain the stabilizing cosφ ≈ 1 effect by application of the special small construction change in the motor.

Quasi-Smart Construction Synchronous Machine Working with Extensive Cycling Load

P. G. Ali-Zade, R. N. Tuncay, S. B. Ozturk, O. C. Kivanc
Conference Papers in Proc. International Conference on Application of Information and Communication Technology and Statistics in Economy and Education (ICAICTSEE - 2012), Oct. 5-6, 2012, pp. 93-101

Abstract

The paper deals with: 1) The controlled exciting systems to keep cosφ ≈1 of the special brushless synchronous motor (SBSM) under cycling load. They are firstly unmanned the deep-well oil pumps drives, wind renewable energy synchronous generators, etc. The machines usually work in harsh climate conditions such as extreme northern cold or deserts hot outside ambient temperatures (rarely up to ±60oC), where traditional electronic controlled exiting systems are not reliable (except diodes). 2) Peculiar approach during project work and construction of the special smart brushless synchronous machine (SBSM); it includes their designs and industrial applications with the simple diode bridge rectifier exciting system with constant current to get selfstabilizing effect of power factor (cosφ ≈1) under wide range of cycling torque; it was made by only special modifications of the motor to put it in smart state for oil field sucker-rod pumps drives

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Duyurular & Bilgilendirme

Sevgili öğrencilerimiz Elektrik-Elektronik Mühendisliği ve Mekatronik Mühendisliği derslerimiz COVID-19 virüs salgını sebebiyle O'Learn üzerinden online olarak 5.Ekim.2020 tarihinde başlayacaktır. Gerekli bilgilendirmeler için lütfen bölüm sosyal medya sayfalarımızı ya da üniversite kurumsal sayfasını ziyaret ediniz.

Ofiste bulamadığınız durumlarda lütfen cihan.kivanc@okan.edu.tr adresine elektronik posta ile bilgilendirme mesajı gönderebilirsiniz.

Duyuru-1: Yürütülmekte olan TÜBİTAK, HORIZON, Teknokent ve KOSGEB projeleri hakkında bilgi/görev almak için mail atabilirsiniz.

Duyuru-2: Güncel Proje Konuları: Kesintisiz Güç Kaynakları, Senkron Relüktans Motor Kontrolü, Elektrikli Araç Şarj Kablosu Geliştirme, İnsansız Kara Aracı Geliştirme, Akıllı Ev Enerji Yönetim Sistemi Geliştirme

Duyuru-3: 2020-2021 Eğitim Yılında Laboratuvarlarımızda görev almak isteyen dördüncü sınıf öğrencileri öğretim üyelerimizle iletişime geçebilirler.

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