Gungor Bal

• PhD
• Professor at Başkent University

Electric vehicles (EVs) are well-known as environmentally friendly systems. Therefore, the demand for EVs is rapidly increasing every day, but for charging batteries of EVs eco-friendly electrical energy sources are needed. To use a clean energy source, this article proposes a wireless power transfer (WPT) system energized by photovoltaic panels. I...

In this study, load frequency control (LFC) of two-area non-reheat thermal power system and multi-source power systems is addressed. A simple PID-structured controller is used as a secondary controller in these systems. To raise the performance of PID controller, a new multi-objective function is designed and PID controller parameters are acquired...

Dünyadaki birçok modern ordu, kendi sistemlerini daha üst seviyeye çıkartmak, rakip güç karşısında üstün gelmek ve savaş alanındaki can kayıplarının önüne geçmek için Artırılmış Gerçeklik (AR) ve Sanal Gerçeklik (VR) araçlarına yatırım yapmaktadır. Bu yatırımlar, dünyadaki güç dengelerini önemli ölçüde değiştirebilir ve bir savaşı kazanma için dikk...

Due to uncontrolled natural variables such as wind speed, the correlation between the renewable energy production and the demand is strenuous. In order to make the renewable enrgy system effective the energy storage systems are utilized employing the, control systems for the enegy in the battery and power. In addition, the rapidly changing wind spe...

In this study, a web based virtual dressing application with help of augmented reality technology is successfully achieved and presented. This application has a structure that uses the computer camera as motion sensor, select the product with remote hand movements and display the selected product as 2D on the user. Nowadays virtual dressing applica...

This paper proposes a new design study for a three-phase permanent magnet motor. The radial flux machine has 12 pole type magnets in its rotor internally and a surface mounted stator has 36 coils surrounding the cores. Initially, a magnetostatic study has been performed, and then a 2D transient finite element analysis has been realized in order to...

In this study, we realized a controller design which can reduce torque ripple of 10/8 Switched Reluctance Motor (SRM). To perform the study, a Switched Reluctance Motor with 5 phase, U type segmental rotor was used. The control of the SRM was actualized by bipolar converter used H-bridge topology. The control signals of converter are obtained by co...

Bu çalışmanın amacı F-16 savaş pilotlarının yüksek teknolojili mühimmatlar kullanarak gerçekleştirdiği silah taktik eğitim çalışmasına benzer, artırılmış gerçeklik (AG) teknolojisini içinde barındıran, eğitim amaçlı basit seviyede bir görev simülatör arabirimi tasarlamaktır. Gerçek F-16 kokpit içinde belirli bir düzende bulunan cihazlar üstün kabil...

Aim of this research is to investigate recent developments on Augmented Reality Technology which is so popular nowadays and creates an enriched environment by adding images to real world images. Whereas in early years the Augmented Reality Technology was considered as limited because of the inefficiency of technological instruments, very expensive...

Aim of this research is to investigate recent developments on Augmented Reality Technology which is so popular nowadays and creates an enriched environment by adding images to real world images. Whereas in early years the Augmented Reality Technology was considered as limited because of the inefficiency of technological instruments, very expensive...

This study presents a precise speed control method for Brushless Direct Current (BLDC) Motors using an electronic tachogenerator (ETg) instead of an electro-mechanical tachogenerator. Most commonly used three-phase BLDC motors have three position sensors for rotor position data to provide commutation among stator windings. Aforementioned position s...

The goal of this study is to address preliminary design and prototyping of a novel 5-phase segment-type switched reluctance motor (SEG-SRM) with 10/8 pole configuration. The proposed SEG-SRM includes a stator having salient poles and a rotor having segmental steel cores which are embedded in aluminum block. The operation of SEG-SRM depends on excit...

Permanent magnet synchronous motors (PMSM) are recently getting involved in many usage areas such as industrial, robotic, home and office applications due to the fact that they have several advantages like fast dynamic response, low size, high efficiency, high power density and more reliability. Since PMSMs require rotor position information for ph...

As is known, machine design is a time-consuming and complicated process. And consequently, the verification of the designs and machine performances with known optimization methods prior fabrication are becoming more complex and expensive. Relating to this issue, many studies have been achieved to realize optimization and analyze dynamic performance...

As is known, machine design is a time-consuming and complicated process. And consequently, the verification of the designs and machine performances prior fabrication are becoming more complex and expensive. Some studies have been achieved to analyze dynamic performance of the designed machines. In this paper, short-circuit fault analysis and transi...

Since automatic control is used in every field, there is almost no industrial application system which doesn’t employ the sensors. It makes correctly reading the data obtained from sensors in the system with sensors and transmitting this data into the computer more important. In this executed study, a design for an interface which can be easily use...

Grounding is the only security precaution to transfer leakage electrical energy on an electrical system to the ground via electrodes and panels placed under the ground. In order to do this transfer, the contact resistance between grounding elements and ground must be very small. Nevertheless, the contact resistance of ground changes with variation...

Bu calismada, enerji hatlari uzerinden haberlesebilen bir mesajlasma sistemi mikro denetleyici tabanli olarak gerceklestirilmistir. Yapilan calisma ile klavyeden yazilan mesajlar LCD ekranda gorunmekle birlikte bu mesaj sinyalleri enerji hatti uzerinden gonderilmekte olup alici tarafta ise enerji hatti uzerinden alinarak LCD ekran uzerinde gozlemle...

Ventilation and refrigeration is indispensable process for human life. Particularly, it has vital importance in desert climate conditions and rural areas, where the grid power may not be available. Although the cost is still higher than traditional energy resources, renewable energy may be the right choice for these applications. In this paper, a D...

This paper introduces the general linear magnetic circuit model of a novel 5-phase segment type switched reluctance motor (ST-SRM) of which rotor cores are embedded in an aluminum block as well as to improve the performance characteristics under simultaneous two-phase (bipolar) excitation of windings. The developed model implements the magneto moto...

Magnetizing inductance is one of the parameters that affect the phase and amplitude error of the output current of current transformers (CTs). In this study, the linear circuit model of a CT is developed to be used for driving purposes in power electronics applications. A simulation of the CT and its linear model is achieved. In the model circuit,...

In this study, a messaging system communicating over power lines was carried out based on microcontroller. The messages written on the keyboard are shown on the LCD (Liquid Cristal Display) and sent over the power line simultaneously. These messages received through power line are displayed on the LCD in the receiver circuit. The message data are c...

Self oscillated resonant inverters have the advantages of low cost and simplicity. DC-AC power conversion can be achieved without using special drivers. In this study, self oscillated half bridge series resonant inverter topology is designed and applied to induction heater as a boiler part of home type absorption cooler system. The designed system...

In this study, microcontroller based powerline communication system is designed and implemented in order to measure and control the temperature of a place. Transmitting and receiving of the temperature data measured with DS18B20 is achieved with help of two microcontrollers called as PIC16F628. Digital bits are transmitted and received periodically...

Self oscillating circuits do not require more complicated control circuit. So they can provide low cost power control with very simple control circuit. Because of these advantages the self oscillating circuit topology is widely used in some power electronics applications such as inverters and electronic ballasts. In this study, an application of se...

Three separate solar farms that provide 15 kW power for each farm are modelled using Matlab Simulink real-time analysis software in this study. Each solar farm models are constituted by connecting 170 W photovoltaic (PV) panels and energy conversion is performed with maximum power point tracking (MPPT) algorithms in each converter. The MPPT algorit...

This article presents a new zero-current switching technique for a single-phase full-bridge sinusoidal pulse width modulation inverter. Two auxiliary switches and a resonant branch are attached to a conventional single-phase full-bridge inverter. The resonant branch can be controlled independently from the main power switches. This technique decrea...

In this study, distance accessed virtual laboratory for an electric machine was established. For this purpose a switched reluctance motor (SRM) was chosen as an example. Simulation of a SRM was achieved with using Matlab&Simulink package program. A LabVIEW program was used to build an Interface between internets and the simulation program. Any stud...

In this paper, dynamic analysis of permanent magnet synchronous motor (PMSM) fed by sinusoidal PWM (SPWM) controlled voltage source inverter (VSI) was studied. Similar to separately excited DC motor, torque and exciting currents are controlled individually by applying vector control technique to the PMSM. Consequently, improving the motor performan...

This paper describes the design and modeling procedure of a novel 5-phase segment type switched reluctance motor (ST-SRM) under simultaneous two-phase (bipolar) excitation of windings. The rotor cores of ST-SRM are embedded inan aluminum block as well as to improve the performance characteristics. The magnetic circuit of the produced ST-SRM is...

This paper is carried out to find out an easy way to determine an advisable and acceptable ratio between stator and rotor tooth width in switched reluctance motors for smoother magnetic field energy, torque and output power profile. As known, different switched reluctance motors (SRMs) have different usage areas because of their different construct...

Among the renewable energy types, wind energy gets popularity in these days. To install a new wind energy turbine, measurement and evaluation of the meteorological data are quite important. In this paper, a novel system is developed for the installation of wind turbines. Firstly, necessary data including the speed and the direction of wind, the sol...

In this study, the speed control of the vector controlled induction motor was implemented by using hard switching and soft switching inverters. A TMS320F243 digital signal processor was used to implement control algorithm during practical implementation. With the use of the vector control, complex structure of the controller is simplified, and depe...

In this study, simulations of two methods used for minimizing the switching losses occur in DC/AC inverters with PWM that is used extensively because of its high power density, fast response and control facility were carried out. First method which can be applied easily is the resonant link inverter. The other one is the resonant transition zero cu...

Researches done based on basic inverter topologies show that multilevel inverters (MLIs) have many advantages, such as low power dissipation on power switches, low dv/dt ratios, low harmonic and low electromagnetic interference (EMI) outputs. The most common MLI topologies have been studied to define the most appropriate structure for Sinusoidal Pu...

In this study, a communication system to send an eight-bits data to the receiver via an energy transmission (power) line was designed and tested. On the transmitter three buttons were used to send three different data to the line. On the receiver side, a buzzer and an LCD screen were used for the voice warning and for indication of the button which...

In this study, simulations of two methods used for minimizing the switching losses occur in DC/AC inverters with PWM that is used extensively because of its high power density, fast response and control facility have been simulated and the losses have been compared. The first method is the resonant link inverter that is easily applicable, the other...

Speed, position and load characteristics of the ultrasonic motor is considerably influenced from the input characteristics such as driving frequency, magnitude and phase difference of phase voltages. Input and output characteristics of a traveling-wave ultrasonic motor have been investigated from the experimental point of view in the present study....

This study introduces original system architecture for the Web based remote experimentation applications for e-learning systems. The speed control of a traveling wave ultrasonic motor (USM) is achieved as a remote experimental study over the Internet to illustrate the architecture. For this reason, a microcontroller based digitally controlled drive...

Piezoelectric driven ultrasonic motors have been attracted as considerable actuators for the servo speed and position applications in recent years. These motors have important features and advantages to be preferred in the special movement applications. Ultrasonic motors have different operating principles and different drive and control systems th...

The goal of this paper is to protect induction motors against possible failures by increasing the reliability, the efficiency, and the performance. The proposed approach is a sensor-based technique. For this purpose, currents, voltages, speed and temperature values of the induction motor were measured with sensors. When any fault condition is detec...

In this study, speed control of a traveling wave ultrasonic motor has been implemented with microcontroller and has been visualized on the computer screen. Digitally controlled a drive system has been developed to control the motor. Speed/position data have been taken from 500 rpm incremental encoder mounted on motor shaft. Comparators circuits hav...

This paper presents a highly effective load adaptive drive system to control the speed of a travelling-wave ultrasonic motor. The motor driver was built based on the two-phase high-frequency inverter using the mechanical resonant frequency of the ultrasonic motor. To digitally control the drive system, a TMS320F243 digital signal processor was adap...

In this paper, position control of an ultrasonic motor was implemented on the basis of fuzzy reasoning. A digitally controllable two phase serial resonant inverter was developed to drive the ultrasonic motor by using a TMS320F243 digital signal processor. The driving frequency was used as a control input in the position control loop. The position c...

In this study a novel servo speed control system for travelling-wave ultrasonic motor (TWUSM) has been presented. A drive system has been built based on two-phase high-frequency inverter using mechanical resonant frequency of the ultrasonic motor. The TMS320F243 digital signal processor (DSP) is adapted to ultrasonic motor drive system. The speed c...

In this study, speed control methods of a travelling wave ultrasonic motor are examined experimentally. A digital controlled drive system is developed to drive ultrasonic motor. The drive system is based on two-phase serial-resonant inverter which includes features of pulse width modulation and pulse frequency modulation techniques. The frequency,...

A digitally controlled drive system was implemented in this study to control the speed and direction of a travelling-wave ultrasonic motor. The drive system, based on a 2-phase voltage-fed high-frequency serial-resonant inverter, uses the mechanical resonant frequency of an ultrasonic motor. A TMS320F243 digital signal processor was used to control...

The estimation of ultrasonic motor characteristics as a function of input parameters, such as the voltage amplitude and driving frequency and as a function of operating conditions, such as load torque and temperature is so important for control of ultrasonic motors. This paper deals with an equivalent circuit model of travelling-wave ultrasonic mot...

A toothbrush/dentifrice abrasion machine was developed to use in dental research laboratory. The mechanism was designed as a hexagonal block driven by two stepping motors which move the mechanism in four directions. In order to control the stepping motors speed, position and direction commands or signals were generated by a software written in C Pr...

Determination of the temperature rise as well as the power dissipated inside induction machines as heat is a matter of interest to both customers and manufacturers. This is important since it affects the insulation materials, the cooling systems and the efficiency of the machine. In this paper, some of established methods of full-load temperature r...

Switched reluctance motors (SRMs) are increasingly popular machines in electric drives, whose performances are directly related to their operating condition. Their dynamic characteristics vary as conditions change. Recently, several methods of modelling of the magnetic saturation of SRMs have been proposed. However, the SRM is nonlinear and cannot...

PWM inverters have been used in industry to control voltage, frequency and harmonics. However the switching devices used in PWM inverters have high switching losses due to the hard switching configuration. Therefore, high frequency resonant DC link inverters have been proposed to reduce the switching losses of power devices. This paper reports a si...

Switched reluctance motors (SRMs) are almost always operated within the saturation region for a very large operation region. This yields very strong nonlinearities, which makes it very difficult to derive a comprehensive mathematical model for the behaviour of the machine. Artificial neural networks (ANNs) have been used to overcome such problems....

In this paper performance analysis of vector controlled permanent magnet synchronous motor(PMSM) has been investigated. ADMC 401 digital signal processor card developed by Analog Devices has been used for control algorithm. Current and speed have been controlled with PI controller. With the vector control method, exciting and torque currents of the...

Nowadays, the topic of improving quality and variety of electric motors comes into prominence in parallel industrial applications and technologic developments. High speed, high torque, low weight, small dimension and longevity are the features wanted from new motors that will be used in industry. In addition, as a result of development in semicondu...

In this paper, a toothbrush/dentifrice mechanism to be used in a dentist research laboratory has been designed and built up. The mechanism has been designed as a hexagonal block driven by two step motors which move the mechanism in four directions. To control the step motors speed, position and direction commands or signals are generated by a softw...

Determination of the temperature rise as well as the power dissipated inside induction machines as heat is a matter of interest to both customers and manufacturers. This is important since it affects the insulation materials, the cooling systems and the efficiency of the machine. In this paper, some of established methods of full-load temperature r...

In this study, an equivalent circuit model of an ultrasonic motor has been given and validation of the model has been examined. Temperature, time and torque parameters which affect the operation of the motor have been added to the model. To obtain the experimental results of the motor, an experimental rig has been set up. Frequency, voltage, torque...

The computer simulation of the EKF, based on data generated from an ideal induction motor model driven by a PWM inverter, may not be a reliable guide to its behaviour when applied to a real system. The selection of the appropriate values of EKF process and measurement covariance matrices requires an empirical method and should be carried out with r...

Indirect field-orientation method is widely used to obtain high dynamic performance from induction motor drives. In order to obtain the full advantageous of this control technique the rotor time constant must be tracked on-line. In this paper, a rotor resistance compensation method based on stator model is proposed. The dynamic performance of the a...