Atıf Sayısı
5
Görüntüleme
24
İndirme
6
Güç sistemlerinin büyümesi, hatlardaki sıkışıklığın artması nedeniyle güç sistemlerinde kararlılık kritik bir konudur. Kararlılık sorunu genellikle talep edilen reaktif gücün karşılanamamasından ve yükteki artışlardan meydana gelmektedir. Yeni hat kurulum maliyetlerinin yüksek olması nedeniyle varolan hatların maksimum kapasitede çalıştırılıyor olması da gerilim kararsızlığına sebep olmaktadır. Gerilim kararlılığında bara gerilimlerinin belirlenen güvenli sınır değerlerde kalması esastır. Gerilim değerleri bu sınırlar aralığında kalmadığı taktirde hem tüketici tarafında hem de şebeke tarafında sorunlara yol açmaktadır. Şebekeden gereğinden fazla reaktif güç çekilmesi hatlarda sıkışıklığa neden olmaktadır. Bu nedenle reaktif güç, gücün tüketileceği yere yakın bir yerden sağlanırsa hem iletim hatlarının gereksiz yüklenmesinin önüne geçilmiş olur hem de kayıplar azaltılmış olur. Ayrıca dağıtım trafoları daha fazla yükü besleyebilir. Sisteme reaktif güç desteği sağlayabilmek ve sistemi kararlı hale getirebilmek için literatürde çeşitli yöntemler kullanılmıştır. Kompanzasyon sistemleri, trafo kademe değiştiricileri, yük atma, FACTS cihazları bunlardan bazılarıdır. Bu çalışma literatürdeki çalışmaların incelemesini içermektedir.
The growth of power systems is a critical subject of stability in power systems due to the increased frequency in the lines. The problem of stability is often caused by the failure to meet the requested reactive power and the increase in load. Due to the high cost of the new line installation, the existing lines are being operated at the maximum capacity also causes voltage instability. It is essential that the bar tensions remain at the defined secure limit values. If the tensions are not within these limits, it causes problems both on the consumer side and on the network side. Excessive reactive power removal from the network causes confusion in the lines. Therefore, if the reactive power is provided from a place close to where the power is consumed, the unnecessary load of the transmission lines will be prevented and the losses will be reduced. Also, the distribution trafoles can feed more burden. A variety of methods have been used in literature to provide reactive power support to the system and to make the system stable. Compansing systems, trafo scale shifts, loading, FACTS devices are some of them. This study includes the study of the works in literature.
The recent use of radars in indoor applications has made them a part of live. The probability of seeing radars anywhere in living area (house, car, street) has increased considerably. In parallel with this increase, radar applications that make life easier have emerged. In particular, the ability of radars to detect the presence of an object without contact has enabled them to find their place in medical applications. Non-contact detection of vital signs with radars is among the remarkable studies recently. Since there is no contact situation (probe, etc.) for the patient in this determination, it provides freedom of movement and also facilitates the work for those who will perform the surveillance. The simple structure of the Frequency Modulated Continuous Wave Radar (FMCW), its low cost, its ability to detect range and its less susceptibility to noise compared to pulse radars make it one step ahead of other radars. In addition, the disadvantage of continuous wave radars (CW) that cannot detect more than one target is eliminated by FMCW radar. FMCW can distinguish multiple targets from each other, depending on the radar range resolution. In this study, chest wall motion due to respiration and heartbeat was simulated and detected by FMCW radar. An algorithm has been presented to make the detection. First of all, the range of the targets is determined and then the vital signs are calculated. By using multiple stationary targets, targets at 5 and 8 meters are detected with 0% and 1.56% error rates, respectively. Respiration and heart rates present at these targets are determined with an error rate of 2.29% for both targets, respectively. The preliminary results show that the FMCW radar has high success in detecting range and the existence of vital signs originating from displacement. It is anticipated that in the future, applications carried out with contact measurements will be replaced by radars.
Alan : Fen Bilimleri ve Matematik; Mühendislik
Dergi Türü : Uluslararası
Makale Detay 
Atıf Yapanlar
Benzer Makaleler
PDF Görüntüle
Dergi Bilgisi
Eseri Dinleyin
Bu Sayfayı Yazdırın
Paylaş
Mendeley
