Hybrid DC/DC Converter for Electric Vehicle (EV) On-Board Charger (OBC) Using Full-Bridge (FB) and Resonant Converter with Single Transformer Najam ul hassan Department of Electrical Engineering Graduate School, Myongji University

Hybrid DC/DC Converter for Electric Vehicle (EV) On-Board Charger (OBC) Using Full-Bridge (FB) and Resonant Converter with Single Transformer Najam ul hassan Department of Electrical Engineering Graduate School, Myongji University Advisor Professor Lee Jun-young

ABSTRACT

In this document a highly efficient hybrid DC/DC converter is proposed. Its design procedure, analysis and experimental results are presented by testing of the implemented prototype and. whole document is arranged into six chapters. Electrical vehicle battery chargers background, power level, different charging methods and purpose of the document is presented in chapter 1. High power DC/DC converter topologies suggested recently, and its benefits and drawbacks are briefly discussed in chapter 2. Proposed converter diagram, operational analysis and comparison of proposed converter with other DC/DC converter topologies are presented in chapter 3. Chapter 4 is about design procedure. Based on the design procedure suggested in chapter 4, prototype design and simulation results are given in chapter 5 and experimental results are given in chapter 6. Most of the previously proposed hybrid converters have used two transformers for each converter in hybrid structure that makes the size of the converter bulky and there was also low utilization and the power distribution problem between two transformers of the hybrid converters. To solve this problem, a new high efficient hybrid DC/DC converters using single transformer, which has characteristics of Full-bridge and resonant convertor for EV OBC, is proposed in this vii thesis. By using single transformer the power distribution problem has been solved and transformer utilization has become high. In the proposed converter, magnetizing inductance has been used at the primary side of the transformer to obtain the soft switching such as zero voltage switching (ZVS). Leakage inductance of the transformer has been used as resonant inductor on the secondary side to avoid the use of separate inductor as resonant. The prototype of 6.6KW has been implemented to verify the feasibility of the proposed converter and maximum efficiency of 97.4 is achieved at 413 V.

LINK http://www.mediafire.com/file/fd3hegpispv96nv/Hybrid_DCDC_CONVERTER_EV_CHARGER.pdf/file

UPS Topologies for the Elimination of Inrush Current Phenomenon Associated with Transformer-Coupled Loads-Syed Sabir Hussain Bukhari Graduate School of Hanyang University

UPS Topologies for the Elimination of Inrush Current Phenomenon Associated with Transformer-Coupled Loads Syed Sabir Hussain Bukhari Department of Electronic System Engineering The Graduate School Hanyang University 

ABSTRACT
 Many critical load applications depend upon UPS system to uphold power in the course of outages as well as during under- and over-voltage grid conditions. Once any disruption occurs at the grid, a UPS system either takes over the load completely or injects the compensation voltage to the load to avoid interruption. For an off-line and line-interactive UPS systems, this transfer of load takes a minimum of 1–5 msec and can be as much as 20 msec, mainly depending upon the time required for the fault detection and the operating mechanisms of the transfer switches. Throughout this time duration, the load transformer, accompanied by the sensitive load is probable to be exposed to the distorted grid voltage. As a result, a flux-offset of the load transformer is established. Thus, as soon as the UPS system takes over the load and reinstates its voltage, the transformer flux might increase above its saturation level and generates substantial inrush current. In the case of an on-line UPS topology, the load transfer time period is zero. The phenomenon of inrush current for an on-line UPS system is observed when it powers multiple transformer-coupled loads. Under such a condition, the switching-in of a load when other loads are already on-line can cause a large magnitude of inrush current because of the energizing of the load transformer. This inrush current can take several cycles, which reduces the line voltages and triggers over-current protecting devices of the UPS systems. In this research, an off-line UPS system based on current regulated voltage source inverter (CRVSI) instead of conventional voltage source inverter is proposed. The inverter of the UPS system utilizes a current control algorithm implemented in the stationary frame. This enables an off-line UPS system to eliminate the inrush current during the transition while powering a transformer-coupled load. To eliminate the inrush current phenomenon related with a line-interactive UPS system and to achieve fast current injection by the inverter during any abnormal grid power condition, a new line-interactive UPS system is proposed in this research that uses a standard current regulated inverter coupled with the secondary of the load transformer. The possibility of inrush current is eliminated with an instantaneous compensation of load current and a seamless transition of a load. This research also proposes an on-line UPS topology with eliminated inrush current while operating with multiple transformer-coupled loads, achieved through a swift performing current regulated inverter operating with a control scheme consists of two control loops to supply the additional current caused by the switching-in of the loads. The outer voltage control loop controls the load voltage. However, the inner current loop controls the load current to vary it sinusoidally as per the supplementary load demand during the engagement of other load transformers, leaving behind any possibility of inrush current generation. All of the above mentioned UPS topologies are well-analyzed and implemented through simulation and experimental results. A comparison between the conventional static UPS topologies and the proposed UPS topologies is also provided in this research.

ORIGINAL LINK:http://www.riss.kr/search/detail/DetailView.do?p_mat_type=be54d9b8bc7cdb09&control_no=e0fe01fc0fc571f5ffe0bdc3ef48d419

LINK http://www.mediafire.com/file/yute4gnsxo2es6n/UPS_Topologies_for_the_Elimination_of_Inrush_Current.pdf/file

A Study on The Control Technique for Modular Three-Phase Uninterruptible Power Supply(UPS) With Boost Converter Jin, Seongmin Dept. of Electrical Engineering Incheon National University-SOUTH KOREA

A Study on The Control Technique for Modular Three-Phase Uninterruptible Power Supply(UPS) With Boost Converter Jin, Seongmin Dept. of Electrical Engineering Incheon National University

ABSTRACT
 This study proposes a control algorithm design and implementation method for the control method of the modular three phase uninterruptible power supply (UPS) with boost function. With the development of the industrial age, there has been an increase in the load required to maintain the constant power source, which has increased the demand for the uninterruptible power supply. In addition, a parallel type uninterruptible power supply unit of a modular type is widely used to satisfy a load of a high capacity It is difficult to apply a desired output voltage to a load by using a 250V DC voltage as the input power source of a UPS used in a power plant system. Therefore, it is necessary to design a module suitable for UPS system for power plant. A UPS for applying 3-phase AC voltage to a load is generally composed of a 3-phase inverter and an output L-C filter. In order to apply this to the power plant system, it is necessary to construct and control a power converter for a single module that boosts the input voltage by applying a boost converter to the input of the inverter to supply the constant voltage to the inverter. In addition, a parallel operation control technique is necessary to solve the problem of connecting such a single module in parallel. Therefore, in this study, the study on the configuration, design and parallel operation control technique for single module UPS for power plant was conducted. The proposed algorithm proved its superior performance and feasibility through simulation and experimental results Key words: Uninterruptible power supply, single module power converter for plant, parallel operation control

LINK A:http://www.riss.kr/search/detail/DetailView.do?p_mat_type=be54d9b8bc7cdb09&control_no=720abcc1b0b8a4c6ffe0bdc3ef48d419

LINK B :http://www.mediafire.com/file/zgqcnslz3p72edt/A_Study_on_The_Control_Technique_for_Modular_UPS.pdf/file

RESOLVIENDO EJERCICIOS DE CIRCUITOS ELÉCTRICOS 1-PROF.DR. ENG. FERNANDO LOPEZ ARAMBURU-LIMA-PERU

ES PARA MI UNA GRANDE SATISFACCION DIFUNDIR EN MI BLOG LOS VIDEOS DE MI ESTIMADO COLEGA DR. ING. FERNANDO LOPEZ ARAMBURU QUE EN MEDIO A LA PANDEMIA DEL CORONA VIRUS SE HA REINVENTADO DICTANDO SUS CLASES DE MANERA VIRTUAL PARA LA UNIVERSIDAD NACIONAL DE INGENIERIA FACULTAD DE ING. ELECTRICA Y ELECTRONICA,EL ES UN DOCENTE CON MAS 30 AÑOS DE EXPERIENCIA HA TRABAJADO EN LA EMPRESA PRIVADA Y HA SIDO PROFESOR DE CIRCUITOS ELECTRICOS EN MUCHAS UNIVERSIDADES ESTATALES Y PRIVADAS DEL PERU,ES CONOCIDO EN LA COMUNIDAD ACADEMICO COMO 'CHAMPION" INGENIERO,DOTADO DE UN CARISMA UNICO DICTA SUS CLASES CON MUCHA DIDACTICA Y ANALISIS CRITICO,LE ENVIO UN CORDIAL SALUDO.

REDES SIMETRICAS-CIRCUITOS ELÉCTRICOS 1-ENG. FERNANDO LOPEZ ARAMBURU-FACULTAD INGENIERIA ELECTRICA ELECTRONICA-UNIVERSIDAD NACIONAL DE INGENIERIA- LIMA PERU