A Study of High Resolution Isolated Multi-Level Inverter for Grid-Tie Renewable Generation System by Noh Sik Park Department of Mechatronics Engineering The Graduate School Pukyong National University

A Study of High Resolution Isolated Multi-Level Inverter for Grid-Tie Renewable Generation System 신재생 발전 시스템의 계통 연계를 위한 고정도 절연형 멀티레벨 인버터에 관한 연구 
Advisor: Prof. Soon Jae Kwon 
by Noh Sik Park 
A thesis submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Department of Mechatronics Engineering
The Graduate School Pukyong National University February 2009
 ABSTRACT 
 The objective of this paper is to contribute to the commercialization of high resolution 3 phase multi level inverter that uses new control method which is properto thegreatcapacity inverter used for Grid-tiedRenewable GenerationSystem.Forthispurpose,thebasicoperationprincipleandtypes of the conventional multi level inverter is divided to describe the each merit and demerit, the modulation technique applicable to multi level inverter, the domestic and overseas standard and protecting technology of grid-tied technology which is indispensable to grid-tied inverter. The loss for each factor in 3 phase multi level inverter that uses low-frequency transformer was analyzed with structure of 3 phase multi level, theoretic investigationontheregularspacevectormodulationmethodandanewcontrol technique so as to calculate all loss that may occur in the proposed inverter. Further, this research explained the control technique applied to anti-islanding, an essential function of grid-tied inverter and confirmed outputwaveformandTHDforeachrateofmodulationbyusingMatrap/Simulink so as to check the technical feasibility of multi level inverter using 3 phase low-frequency transformer. As 3 phase multi level inverter in 30kW isolate type was designed, produced and experimented, it was confirmed that the performance which was not inferior to that of the existing 2 level inverter method was embodied. Since there is no particular difficulty in productioncomparedtotheexistingproductswhichareproducedbydepending on many know-hows and less part was technically restricted in producing inverter with capacity larger thanthatof inverter produced forresearch, it presents the possibility of localizing power transformer for Grid-tied RenewableGenerationSystemwhichgetslarger
LINK
http://www.mediafire.com/file/vqs3pl4rkq4ezao/A_Study_of_High_Resolution_Isolated_Multi-Level_Inverter_for_Grid-Tied_Renewable_Generation_System.pdf

Analyse des contraintes mecaniques par la methode des elements finis dans une machine electrique - Mechanical Stress Analysis by the Finite Elements Method in Electric Motor CHANG- HOON JUN Thesis(doctoral)-- L'ecole centrale de Lyon-Genie electrique

Analyse des contraintes mecaniques par la methode des elements finis dans une machine electrique - Mechanical Stress Analysis by the Finite Elements Method in Electric Motor CHANG- HOON JUN Thesis(doctoral)-- L'ecole centrale de Lyon: Genie electrique 1998
 LINK
http://www.mediafire.com/file/szn14jrp6xsl916/09590683.pdf

BREAKDOWN VOLTAGE PERFORMANCES OF ALUMINUM AND COPPER CONDUCTOR WIRE UNDER COMPRESSION STRESSES -Richard Donald Suchanek - Western Kentucky University Master of Science

BREAKDOWN VOLTAGE PERFORMANCES OF ALUMINUM AND COPPER CONDUCTOR WIRE UNDER COMPRESSION STRESSES 

A Thesis Presented to The Faculty of the Department of Architectural and Manufacturing Sciences Western Kentucky University Bowling Green, Kentucky
 In Partial Fulfillment Of the Requirements for the Degree Master of Science By Rich Suchanek
May 2016
 ABSTRACT
 In the global, competitive market of energy transformation, increased operational expenses and depletion of raw materials have resulted in companies pursuing alternate materials to reduce consumer costs. In electrical applications, energy is transformed using materials with high electrical conductive properties. The conductive material used to transmit a signal is called conductor wire and is comprised of any material that has the ability to move charged particles from one point to another without propagation or delay. The conductor wire in many applications is encapsulated in epoxy resin called enamel. The enamel is the insulation system that provides necessary dielectric clearances to prevent voltage leakage. The most common form of energy transformation is the electric motor. Both copper and aluminum conductor wire are commonly used in electric motors, but copper is preferred due to thermal and electrical properties. However, there is a significant economic incentive to convert to aluminum conductor wire. Limited white papers are available comparing the performances of the two materials; the research is limited to physical and electrical performances of the raw material and does not take into considering the insulation. The conductor wire, which includes the insulation, is susceptible to damage during the manufacturing process and is an inherent risk if not fully understood. During the blocking process, the conductor wire is pushed and compressed into lamination slots. This process changes the conductor wire outer diameter to accommodate void spaces within the lamination slots. The percentage of slot vii area occupied by the conductor wire is known as slot fill. The higher the slot fill, the more wire occupying the available space. The higher the slot fill, the more force required to fill the slots. High slot fill motor designs provide a performance advantage with little associated cost. The more wire pressed into the slot, the higher the potential efficiency gains. However, high slot fill motors are more susceptible to damage. The study is designed to evaluate and measure the durability of aluminum and copper conductor wire under simulated compression stresses. Utilizing this information, electric motor manufacturers can push current design limits without affecting conductor wire quality and reliability.
FULL THESIS LINK ORIGINAL:
http://digitalcommons.wku.edu/cgi/viewcontent.cgi?article=2611&context=theses

直播回放: 神舟十一号与天宫二号交会对接, 航天员进入天宫二号 | Full Replay: Shenzhou 11 Spacecraft Dock With Tiangong 2 Space Lab

LINK
https://youtu.be/jKvZmmUfLSo

Live: Chinese astronauts enter Tiangong-2 space lab from Shenzhou-11 spacecraft

China's manned spacecraft, Shenzhou-11, docks with space lab Tiangong-2. The spacecraft was launched into orbit on Monday, carrying two astronauts who plan to stay in the space lab for 30 days. The crewed mission marks a key step toward China's plan to eventually operate a permanent space station.