A Hybrid PV-Battery/Supercapacitor System and a Basic Active Power Control Proposal in MATLAB/Simulink

Blaabjerg, Frede/0000-0001-8311-7412; sahin, mustafa ergin/0000-0002-5121-6173WOS: 000516827000129An increase in the integration of renewable energy generation worldwide brings along some challenges to energy systems. Energy systems need to be regulated following grid codes for the grid stability and efficiency of renewable energy utilization. the main problems that are on the active side can be caused by excessive power generation or unregulated energy generation, such as a partially cloudy day. the main problems on the load side can be caused by excessive or unregulated energy demand or nonlinear loads which deteriorate the power quality of the energy networks. This study focuses on the energy generation side as active power control. in this study, the benefits of supercapacitor use in a hybrid storage system are investigated and analyzed. A hybrid system in which photovoltaic powered and stored the energy in battery and supercapacitor are proposed in this study to solving the main problems in two sides. the supercapacitor model, photovoltaic model, and the proposed hybrid system are designed in MATLAB/Simulink for 6 kW rated power. Also, a new topology is proposed to increase the energy storage with supercapacitors for a passive storage system. the instantaneous peak currents energy is aimed to store in supercapacitors temporarily with this topology. the main advantages of this topology are voltage stabilization in two sides by the supercapacitors and a limitation of the battery load, which directly results in longer battery life and decreases the system cost. the simulation results are investigated for this topology.Scientific&Technological Research Council of Turkey (TUBITAK), 2219 postdoctoral research program [1059B191700997]This study was supported through the Scientific&Technological Research Council of Turkey (TUBITAK), 2219 postdoctoral research program with a 1059B191700997 application number

Design of wave energy converter system with linear generator

International Conference on Computational and Experimental Science and Engineering (ICCESEN) -- OCT 25-29, 2014 -- Antalya, TURKEYsahin, mustafa ergin/0000-0002-5121-6173WOS: 000363011700070It is not wrong to say that wave energy will be one of the most important energy sources to be used in the future, when it is thought that three-quarters of the world is covered by water. the initial investment and maintenance costs are the only expenses, beside not any price have to be paid for the primary energy. the wave energy does not leave any contaminants, as well as it is cheap, clean, environmentally, friendly and a great energy sources. in this study, wave energy converter system which has a four poles linear generator is discussed. the Linear generator model has been designed and created as a portable model. the results obtained from this model were examined

A MATLAB/GUI based photovoltaic system simulator for estimation of PV parameter using newton-raphson method

Bu çalışmada ilk olarak güneş pilinin çalışma prensibi, bileşenleri ve bağlantı şekilleri ile eşdeğer devre modeli çıkarımı incelenmiştir. Fotovoltaik (FV) güneş pili modülü genel eşdeğer devre modeli matematiksel denklemleri MATLAB programına uyarlanmıştır. Güneş pilinin akım denklemi çözümü için Newton-Raphson yöntemi kullanılarak MATLAB grafiksel kullanıcı ara yüzü (GUI) ortamında bir ara yüz oluşturulmuştur. Kullanılan model güneş ışınımı ve sıcaklık gibi değişen çevresel koşulları da içerecek şekilde tasarlanmıştır. Oluşturulan ara yüz ile kullanıcı; ışınım, sıcaklık, seri direnç, ideallik faktörü ve seri-paralel bağlı hücre sayıları gibi parametreleri değiştirerek akım ile gerilim (I-V) ve güç ile gerilim (P-V) eğrilerini kolayca elde edebilmektedir. Bu çalışmada iki ayrı üretici firmaya ait güneş paneli verileri için farklı parametreler kullanılarak karakteristik eğriler elde edilmiştir. Ayrıca kullanıcı bu ara yüz sayesinde fotovoltaik hücrenin değişken değerlerini girerek maksimum akım (Imp), maksimum gerilim (Vmp), maksimum güç (Pmp), giriş gücü (Pin), doldurma faktörü (DF) ve verim (η) gibi değerleri kolaylıkla elde edebilmektedir. Bu sayede bu alanda çalışanlar için kullanıcıya kolaylık sağlayan bir ara yüz geliştirilmiştir.In this study, the working principle, components and connection types of the solar cell and the equivalent circuit model extraction were examined. The mathematical equations of the photovoltaic (PV) solar cell module general equivalent circuit model were adapted to the MATLAB software. An interface was created in the MATLAB GUI environment using the Newton-Raphson method to solve the current equation of the solar cell. The model used also includes changing environmental conditions such as solar radiation and temperature. With the interface created, the user; can quickly obtain Current-Voltage (I-V) and Power-Voltage (P-V) curves by changing parameters such as radiation, temperature, series resistance, ideality factor and number of cells connected in series-parallel. In this study, characteristic curves were obtained by using different parameters for the solar panel data of two other manufacturers. In addition, the user can quickly get values such as maximum current (Imp), maximum voltage (Vmp), maximum power (Pmp), input power (Pin), filling factor (FF) and efficiency (η) by entering the variable values of the photovoltaic cell through this interface. In this way, an interface that provides convenience to the user has been developed for those working in this field

A Hybrid Efficient PV-Battery Powered LED Lighting Scheme

As we all know now a day�s developing countries across Asia and Africa are hit with the serious energy crisis. So To fulfill the power demand people started looking towards renewable sources of energy such as solar and wind energy. In this paper fully controlled, flexible and self-adjusting LED lighting PV-Battery powered scheme using a pulse-width modulation (PWM) switching and controlled by a dual-loop error driven, time de-scaled, WM proportional-integral-derivative (WM-PID) control scheme for the PV-battery interfaced to the LED load. It decreases the amplitude of transient voltage and minimize inrush current for balancing common DC bus to the LED load. The new adjustable controller uses a directed dual-loop error-driven, error-time descaled controller for the PWM switching along with MOSFET/IGBT switches. The dual-action regulator uses error driven weighted modified (WM-PID) proportional-integral-derivative controller with quick response auxiliary derivative loops to achieve efficient control action

The Relationship Between Arthroplasty Surgeons' Experience Level and Optimal Cable Tensioning in the Fixation of Extended Trochanteric Osteotomy

Introduction: In this study, our aim was to examine the relationship between the arthroplasty surgeons' experience level and their aptitude to adjust the cable tension to the value recommended by the manufacturer when asked to provide fixation with cables in artificial bones that underwent extended trochanteric osteotomy (ETO). Materials and Methods: A custom-made cable tensioning device with a microvoltmeter was used to measure the tension values in Newtons (N). An ETO was performed on 4 artificial femur bones. Surgeons at various levels of experience attending the IXth National Arthroplasty Congress were asked to fix the osteotomized fragment using 1.7-mm cables and the tensioning device. The participants' demographic and experience data were investigated and recorded. The surgeons with different level of experience repeated the tensioning test 3 times and the average of these measurements were recorded. Results: In 19 (35.2%) of the 54 participants, the force applied to the cable was found to be greater than the 490.33 N (50 kg) value recommended by the manufacturer. No statistically significant difference was determined between the surgeon's years of experience, the number of cases, and the number of cables used and the tension applied over the recommended maximum value (P = .475, P = .312, and P = .691, respectively). Conclusions: No significant relationship was found between the arthroplasty surgeon's level of experience and the adjustment of the cable with the correct tension level. For this reason, we believe that the use of tensioning devices with calibrated tension gauges by orthopedic surgeons would help in reducing the number of complications that may occur due to the cable

İstanbul İlinde Görev Yapan Kamu ve Özel İlköğretim Öğretmenlerinin İş Tatmin Düzeylerinin Belirlenmesine Yönelik Bir Araştırma

DergiPark: 326420trakyasobedEven though it has been observed that the number of researches relating to job satisfaction made recently has increased, the number of researches which determine the satisfaction level that the teachers who are the milestones of education feel for their work is very few. The main survey field of the work can be summarized as measuring of the job satisfaction level of the teachers who work at public and private elementary schools within Istanbul, comparing the levels obtained and presenting the reasons if any, also statistically analyzing the minor factors of job satisfaction conceptSon yıllarda yapılan iş tatmini araştırmalarının sayısında artış gözlense de eğitimin temel taşları olan öğretmenlerin işlerinden aldıkları tatmin düzeylerini belirleyen araştırmaların sayısı çok fazla değildir. Çalışmanın temel inceleme alanı İstanbul ili dahilinde kamu ve özel ilköğretim okullarında çalışan öğretmenlerin iş tatmin düzeylerinin ölçülmesi, elde edilen bu düzeylerin ve alt düzeylerin karşılaştırılması, farklılar varsa nedenlerinin ortaya koyulması ve alt düzeylerin istatistiki olarak ele alınmasıdı

The efficacy and safety of omalizumab in refractory chronspontaneous urticaria: Real-life experience in Turkey

Introduction: This study used real-world data to evaluate the effectiveness and reliability of omalizumab in treating recalcitrant chronic spontaneous urticaria in Turkish patients. Methods: Study data were collected retrospectively from eight tertiary-care hospitals in Turkey. This study included 132 patients with chronic spontaneous urticaria that were resistant to H1 antihistamine treatment in a dose up to four times the licensed dose and were treated with 300 mg/month of omalizumab for 6 months. Results: The mean weekly urticarial activity score (UAS7) after omalizumab treatment improved significantly compared to the pretreatment score (p <0.001). Treatment response was detected primarily in the 1st and 2nd months after treatment. No significant association was observed between omalizumab’s treatment effectiveness and disease-related parameters or laboratory data. The mean dermatology life quality index was 23.12 ± 6.15 before treatment and decreased to 3.55 ± 3.60 6 months after treatment (p <0.001). No side effects were reported in 89.4% (118) of the patients. Conclusion: This study showed that UAS7 decreased significantly and quality of life improved in omalizumab-treated patients. Moreover, treatment effectiveness was mainly observed in the first 2 months after treatment. However, no association was observed between omalizumab treatment effectiveness and disease-related parameters or laboratory data

Serum Neopterin and Procalcitonin Levels in Relationship with Pediatric Burn Wound Infections

Infection and septic complications in burn patients can be monitored by procalcitonin (PCT) and neopterin plasma values. The aim of the study was to investigate serum neopterin and PCT levels with WBC (white blood cell) and CRP (C-reactive protein) levels in patient group (PG) and healthy control group (HCG) and to investigate the relationship of these markers with burn wound infections (BWI). As the PG, 23 patients between 0–12 ages and up to 30% Total Body Surface Area (TBSA) burned and 15 HCG were included. PCT, neopterin, WBC, and CRP results on the first, the seventh, the fourteenth and the 21st day have been compared. During the follow-up period, 11 patients with BWI and 12 patients without BWI were classified as infected and non-infected patients, respectively. PCT and neopterin levels were detected higher in patients with BWI but no significant difference were present. Also, PCT and neopterin levels within the first 24 hours following the burn were detected higher in PG than HCG. CRP and WBC levels were detected high due to burn trauma. PCT and neopterin levels were increased in patients with BWI. PCT levels were increased during the pre-infectious period, while neopterin levels increased during the post-infectious period