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With the widespread use of electric vehicles (EVs), the design of a highly quality and efficient battery charger has become an important research topic. In this study, an efficient AC-DC power factor corrected (PFC) boost converter with active snubber cell (ASC) is proposed for the battery charger. ASC integrated into the AC-DC PFC boost converter turns on the main switch with zero voltage transition (ZVT) and turns off with zero current transition (ZCT), which among soft switching techniques for eliminating the switching losses. In addition, it has been provided that other switching elements are operated with soft switching. Soft switching conditions and unity power factor (PF) are achieved from light load to full load conditions. Unlike the soft-switched PFC converter circuits in the current literature, no current and voltage stresses have been observed on any component in the main converter and ASC circuits. The paper also presents the steady-state operating principles and design guidelines of the proposed converter in detail. The efficiency improvement between the hard switched counterpart has been verified by making detailed loss analysis. The proposed converter has been constructed as 3.3 kW and tested according to European efficiency standards with various case studies. The total harmonic distortion (THD) of input current has been measured as less than 5% in compliance with EN 6100-3-2 Class D Limits (A) standards.

This paper puts forward to Fuzzy Logic MPPT (Maximum Power Point Tracking) method applied photovoltaic panel sourced boost converter, under variable temperature (25–60 °C) and irradiance (700–1000 W/m2) after that the PI control was applied buck converter to behave as a charge controller. The voltage and current of PV panels are nonlinear and they depend on environmental conditions such as temperature and irradiance. Variable environmental conditions cause to change voltage, current and also cause to change maximum available power of PV panels. To increase efficiency and decrease payback period of the system, it needs to operate PV panels at maximum power point (MPP). Under any environment conditions there is unique MPP. To operate PV panels at that point (MPP) there are many MPPT method in literature, FLC MPPT method was preferred in this study because, its rapid response to changing environmental conditions and not affecting by change of circuit parameters. The accuracy of FLC MPPT method used in this system to find MPP changes, from 94.8% to 99.4%. To charge a battery there are two traditional methods which are constant current (CC), and constant voltage (CV) methods. For fast charging with low loss constant current and voltage source is a need. One of the methods providing constant is PI control which used in this study. PI control is not only well developed and a simple technique but also it provides satisfactory results. The goal of this study is operating PV panel at maximum power point under variable environment conditions to increase efficiency and reduce cost and also provide appropriate current and voltage for charging battery to charge quickly, reduce losses and also increase life cycle of battery. This system was established and analyzed in MATLAB/Simulink.

In this paper, the methods used to control voltage source inverters, which have been intensively investigated in recent years, are compared. Although the most efficient result is obtained with the least number of switching elements in the inverter topologies, the method used in the switching is at least as effective as the topology. Besides, the selected switching method to control the inverter will play an effective role in suppressing harmonic components while producing the ideal output voltage. There are many derivatives of pulse width modulation techniques that are commonly used to control voltage source inverters. Some of widespread methods are sinusoidal pulse width modulation and space vector pulse width modulation techniques. These modulation techniques used for generating variable frequency and amplitude output voltage in voltage source inverters, have been simulated by using MATLAB/SIMULINK. In addition, the total harmonic distortions of the output voltages are compared. As a result of simulation studies, sinusoidal pulse width modulation has been found to have more total harmonic distortion in output voltages of voltage source inverters in the simulation. Space vector pulse width modulation has been shown to produce a more efficient output voltage with less total harmonic distortion.

Turksoy, Omer/0000-0003-4620-4503, WOS: 000492797300026, The energy efficiency of the battery charging system directly affects the distance which electric vehicles can get with per charge process. In addition, reducing current harmonics distortion (THD) increases the electrical quality and power conversion performance. This paper proposes intelligent control of high-efficiency two-stage battery charger topology for electric vehicles (EVs). In the first stage, for low harmonics of input current, high power factor and high efficiency, the average current mode controlled ac/dc boost power factor (pf) correction method constructed and analyzed with 98% efficiency and the power factor is achieved higher than 0.99. Additionally, in the second stage, for high energy efficiency, higher battery lifespan and allowing EVs to get more miles with per charge, a half-bridge LLC resonant converter controlled with a designed artificial neural network (ANN). Moreover, the LLC resonant converter controlled under dynamic load to analysis system from no-load to full-load. A 3.1 kW powered system has been designed for this study, the efficiency of the system has been calculated based on European efficiency standards and the peak efficiency of the whole system is 96.2%, the load voltage ripple is less than 0.5 V and also total harmonic distortion of the source current is less than 5%. (C) 2019 Elsevier Ltd. All rights reserved.

WOS: 000490998600002, A dynamic voltage compensator (DVC) technique is presented for the minimizing of the capacitance value of the interleaved power factor corrected (PFC) boost converter for the battery charger in electric vehicles. This technique is based on eliminating the ripple on the capacitor by creating a voltage in the opposite direction as well as the amount of ripple on the capacitor. With the proposed method, the capacitance value is reduced by approximately five times. Reducing the size of the capacitor also provides the use of film-capacitors with a longer life. The other contribution of this study is designing a faster and more stable fully-digital control system, instead of the commonly used analogue controller of interleaved PFC boost converter. A 3.3 kW interleaved PFC boost converter is designed to verify the effect of the designed dynamic voltage compensator and digital controller., Scientific Research Project Unit of Cukurova UniversityCukurova University [FDK-2018-11231], This research study is supported by the Scientific Research Project Unit of Cukurova University with the project number of FDK-2018-11231.

This paper proposes to Flyback converter sourced photovoltaic (PV) Panel is controlled by PI technology, under variable irradiance (800 W/m2 to 1000 w/m2) and temperature (25 °C to 40 °C). The system was used to charge Lithium ion battery for PV panel applications. Voltage and power of PV panels are nonlinear they depend on environment conditions like irradiation and temperature. PV system can be thought as a DC (direct current) source so that one of the DC-DC converters, flyback converter, is used to regulate voltage and current of the PV panel. Flyback converters provide insulation between load and source also by adjustable turn ratio of transformer the load voltage can be regulated. PI control applied to switch (MOSFET) of flyback converter to regulate duty cycle of PWM (Pulse Width Modulation), to charge battery with constant voltage method. The maximum power point of PV module which used in this system, under STC (1000 W/m2 and 25 °C), is around 50 W and the load power of the flyback converter in that condition is around 40 W. The efficiency of system under STC is around 80 %, but when irradiation level decreases to 800 W/m2 and the temperature step up to 40 °C the efficiency of system increases (>95 %). The system was analyzed and constructed in Matlab1Simulink.

Tularemia is a disease that has been reported in Turkey since 1936. Although mice are considered to have a role in the transmission of Francisella tularensis to man, this has not been exactly confirmed yet. The aim of this study was to investigate the presence of F. tularensis in mice by using culture, serology and molecular methods. For this purpose, four villages (Edirne-Demirkoy, Kirklareli-Kaynarca, Tekirdag-Muzruplu, Tekirdag-Sinanli) were selected in Thrace Region of Turkey where tularemia cases had been reported previously. A total of 126 live-catch mouse traps were established in warehouses, barns, areas near wells, water tanks and creeks in the villages in December 2012. Traps were kept overnight and the next day the animals collected were identified at species-level. The live-captured mice were anesthetized and their heart blood samples were obtained. Subsequently, liver and spleen tissues were removed from every mouse under aseptic conditions in the class-2 safety cabinet. These tissues were cultivated in Francis medium containing 5% sheep blood, 0.1% cystein, 1% glucose and incubated for seven days in both normal atmosphere and 5% carbondioxide incubator at 37°C. Tularemia microagglutination test was performed by using the sera which were obtained from live-captured mice. Finally, DNAs were isolated from both liver and spleen tissues of mice, and real-time polymerase chain reaction (Tularemia RT-PCR; Public Health Agency of Turkey, Ankara) were performed. In our study, a total of 19 mice were captured and of these 11 were alive. Ten mice were identified as Apodemus flavicollis, seven were Mus macedonicus and two were Mus musculus. There were no Francisella tularensis isolation in the cultures of mice liver and spleen tissues. Serological tests yielded negative results for 10 mice whose serum samples could be obtained. In RT-PCR, positivity were detected in spleen tissues of two mice which were captured from Kaynarca where first tularemia cases in Turkey in 1936 were reported but has no report from then on. One of them was a live female Mus macedonicus, and the other was a dead male Apodemus flavicollis. In quantitative evaluation, number of microorganism per organ were calculated as 4 x 103 cfu/spleen in Mus macedonicus and 4 x 104 cfu/spleen in Apodemus flavicollis. This is the first study in Turkey indicating that the mice in natural environment harbored F.tularensis. In conclusion, the results of this study indicated that the agent of tularemia has been retained since 1936 in Kaynarca region and this persistence might present a potential risk for tularemia epidemics.