BİR MANYETİK SİSTEMİN MAXWELL 3D ALAN SİMÜLATÖRÜ İLE STATİK MANYETİK ANALİZİNİN ÇÖZÜM SÜREÇLERİ

Bu çalışmada Ansoft firmasının “Maxwell 3D” isimli  statik manyetik çözücüsü incelenmiştir. Statik manyetik alan çözücü Sonlu Elemanlar Yöntemiyle 3 boyutlu analiz yapmaktadır.  Öncelikle modellenecek sistem dörtyüzlü elemanlara bölünür ve sonlu elemanlar ağı oluşturulur. Çözüm sürecinde iterasyonlarla ağlar iyileştirilerek hata azaltılır. Alan çözümüne başlamadan önce iletkenlerdeki iletim akımının  simülasyonu yapılır ve alan çözümü başlar. Sonlu eleman ağındaki her dörtyüzlü elemanın kenarlarının orta noktalarındaki H manyetik alan şiddeti akım yoğunluğu kullanılarak hesaplanmaktadır. Manyetik nüve malzemesinin doğrusal olmaması halinde Newton-Raphson yöntemi manyetik alan şiddeti, H hesaplaması için kullanılmaktadır. Ayrıca doğrusal olmayan bir problemin çözümünün doğrusal bir yaklaşımla yapılması için, malzemenin B-H eğrisi kullanılır. Bu yaklaşım ile H’nin doğrusal olmayan çözümü için yakın sonuçlar elde edilir. Çözücü tamamladığı çözümü bir dosyaya yazar ve hata analizini icra eder. Çözücü adaptif analiz ile en  hatalı dörtyüzlü elemanları küçülterek, belirlenen kriter yerine gelene kadar çözüme devam eder. Sonuç olarak endüktans değerleri hesaplanır, akım yoğunluğu, manyetik alan şiddeti, manyetik akı yoğunluğu, kuvvetler ve   torklar genlik ve vektörel olarak elde edilir. Ayrıca 6/4 kutuplu bir ARM’nin ve 6 kutuplu bir alternatörün statik manyetik çözümü ile elde edilen  parametrik ve görsel sonuçları örneklendirilmiştir

A medium frequency transformer design for spot welding machine using sizing equation and finite element analysis

In this study, a medium frequency power transformer has been designed analytically and its sizes have been obtained. The transformer’s analyses were made numerically by 2D AnsysMaxwell Solver software package. The Solver has also helped to study suitable transformer core and winding samples. Unlike medium frequency transformer, which is generally driven by unipolar PWM method, the designed transformer is driven by bipolar PWM method in the study. The core losses were obtained for different core materials (Trafoperm N3 and Amorfous 2605SA1) by AnsysMaxwell numerical and analytical calculations. The calculated losses for no-load working conditions were compared with each other. The designed transformer has been analyzed for its noload and loaded working conditions magnetically. Finally, the radial and axial forces created in the windings have also been examined for loaded working condition

INVESTIGATION OF THE FACTORS AFFECT PHASE INDUCTANCE IN SWITCHED RELUCTANCE MOTORS

In this study, the factors affecting change of the phase inductance in a switched reluctance motor (SRM) have been investigated. The motor inductance is a function of both excitation current and rotor position and it depends on motor geometry, relative permeability, saturation and fringing and end-turn field. Non-linearity of SRM leads to difficulties for the development of analytical methods for predicting the flux linkages, co–energy change and inductance at all rotor positions these effects in the 6/4 SRM obtained from analytical way and predicted by 3D finite element method (Ansoft RMxprt, Ansoft Maxwell 3D) have been investigated. Results of simulations and analytical solutions have been relatively compared

DESIGNING A CAN BASED ATM FIELDBUS

The Controller Area Network (CAN) bus was initially introduced for automotive applications, but due to its low cost, high speed and high reliability, it has also become a standard in industrial distributed real-time control applications. Asynchronous Transfer Mode (ATM) is a high speed network technology that aims to combine all types of communication, that is, data, voice, and image in a single network structure. Various studies have been carried to incorporate existing network types such as Ethernet and Token Ring with ATM. It is also important to cover the FieldBus communication in this concept. This study aims to incorporate ATM technology with the FieldBus communication. In this concept, CAN based ATM bus structure is introduced. This structure also introduces an opportunity to connect FieldBus networks with ATM seamlessly. Simulation studies have been carried out to validate the introduced model and the results showed that it is feasible to implement the system

ANAHTARLAMALI RELÜKTANS MOTORLARDA FAZ ENDÜKTANSINA ETKİ EDEN FAKTÖRLERİN İNCELENMESİ

Bu çalışmada bir anahtarlamalı relüktans motorda, (ARM) faz endüktansının değişimine neden olan faktörler incelenmiştir. AR motorunun faz endüktansı, uyartım akımı ve hareket eden rotor pozisyonunun bir fonksiyonudur. ARM'nin doğrusal olmayışı bağ akılarını, ko–enerji değişimini ve her rotor pozisyonundaki endüktansını tahmin etmek için bir analitik yöntem geliştirmeyi zorlaştırır. Ayrıca faz endüktansının değişimi motor geometrisine, ortamın bağıl geçirgenliğine, doyuma, saçaklanma ve uç-sargı alanlarına bağlıdır. Bu çalışmada, 6/4 bir ARM'de geometrik yapı, geçirgenlik, doyum, saçaklanma ve uç-sargı alanları etkileri analitik ve 3 boyutlu sonlu elemanlar yöntemiyle (Ansoft RMxprt, Ansoft Maxwell 3D kullanarak) incelenmek istenmiştir. Yapılan simülasyon ve analitik çözümlerden elde edilen sonuçlar karşılaştırılmıştır

The Proposition to Safety of a Lightning Protection System for High Structures

This paper deals with investigation of safety for lightning protection of high structures. It has been also put forth that rolling – sphere method have advantageous and disadvantageous of have been analysed. Designing an air-termination system has shown that the graphical method of the "rolling sphere" is a powerful analysis in studying globally the interactions both among the structures on the roof of the same object and among the structures of surrounding technological installations, and constructions

Portable ECG design and application based on wireless sensor network

In this study, in order to follow the heart signals of patients that needs to be monitored instantly and continuously without mobility restrictions, a portable electrocardiogram circuit is designed. After performing the detection, upgrading, cleaning and digitizing of ECG signal received from patient via disposable electrodes, ECG signals was performed that transmit to a central node with Wireless Sensor Network (WSN) based on ZigBee 802.11.4 standard. Central node is connected to the serial port of a computer. Received data from the central node is processed on computer and continuous flow graph is obtained. The obligation to use wires for tracing patients’ ECG has been removed with this portable system. As it can be seen in this study, thanks to WSN’s property of forming network by itself and its augmentable loop property, the restrain of ECG signals to reach far away distances can be surmounted. The transmission of biological signals with WSN will light on many studies that follow of patients from a distance.</span

Factor Model for Online Education during the COVID-19 Pandemic Using the IoT

Coronavirus disease (COVID-19) has spread quickly around the globe. COVID-19 has affected the education sector due to partial or complete lockdowns that were implemented throughout the world between 2019 and 2022. This pandemic severely affected the education sectors in developing countries such as Pakistan. All the educational institutions in Pakistan turned to online education. However, the education sector lacked the teaching experts, digital experts, the Internet of Things (IoT), and resources needed for online education. The shift from traditional to online education has created many challenges for developing countries during a pandemic such as COVID-19, for example, access to the IoT. This paper aims to introduce the factor model (F model), which will provide guidelines for the government and universities for minimizing the deficiencies related to online education. The F-model will identify all the factors that affect the performance and guide the user about their importance. This will allow the user to resolve that issue and improve the performance of their department or institution. Thus, the F model will benefit the education sector by mitigating the challenges related to online education. The F model is not only confined to online education but can be operated in the fields of science and industry for data extraction and the calculation of results. First, the data is collected physically and online through a student survey related to the challenges of online education during a pandemic. The data extraction and the calculation of the results are carried out using the F model. The results of the survey are alarming and the government has a lot of work to do to improve online education using the IoT. According to the F model, the government should take serious action to improve the performance of students, teachers, and all education sectors not only during the COVID-19 pandemic but also for possible future pandemics

Designing a Virtual laboratory for Simulating to Production of Nanocomposite NdFeB Magnets

The talent figure for a permanent magnet is the multiplication of the maximum energy (BHmax). Less volume magnet is required for the production of magnet flux density if the BHmax value is higher. Mathematical functions are obtained from the data related to resiudal flux density, magnetic coercitivy, permanent magnet flux product capability, Curie temperature and density which were obtained as a result of the studies on different NdFeB alloys in the laboratory. Besides this, mathematical functions of NdFeB hard magnet’s resiudal flux density are obtained by adding elements. In this study, a virtual laboratory for producing nanocompositedNdFeB magnet has been designed. The virtual laboratory software has been used to simulate NdFeB hard magnets for industrial utilities

FEM Based Multi-Criterion Design and Implementation of a PM Synchronous Wind Generator by Fully Coupled Co-Simulation

This study deals with analyzing, designing and fabricating of a 1 kW PM synchronous generator for gearless and direct drive off-grid wind turbines. Performance characteristics of this generator have been calculated analytically in collaboration with dynamic transient coupled-field analysis. All specifications of the PMSG have been investigated and optimized by using finite element method and parametric multi-criterion design approach. At the end of research, a prototype has been fabricated based on the optimized dimensions. Furthermore, the analytical calculations present along with experimental studies carried out for different shaft speeds and load levels. The comparative experimental studies have verified effectiveness of the optimized designing and dynamic co-simulations