Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Transactions on Electrical and Electronic Materials
Journal Basic Information
Journal DOI :
The Korean Institute of Electrical and Electronic Material Engineers
Editor in Chief :
Volume & Issues
Volume 17, Issue 4 - Aug 2016
Volume 17, Issue 3 - Jun 2016
Volume 17, Issue 2 - Apr 2016
Volume 17, Issue 1 - Feb 2016
Selecting the target year
UPFC Device: Optimal Location and Parameter Setting to Reduce Losses in Electric-Power Systems Using a Genetic-algorithm Method
Mezaache, Mohamed ; Chikhi, Khaled ; Fetha, Cherif ;
Transactions on Electrical and Electronic Materials, volume 17, issue 1, 2016, Pages 1~6
DOI : 10.4313/TEEM.2016.17.1.1
Ensuring the secure operation of power systems has become an important and critical matter during the present time, along with the development of large, complex and load-increasing systems. Security constraints such as the thermal limits of transmission lines and bus-voltage limits must be satisfied under all of a system’s operational conditions. An alternative solution to improve the security of a power system is the employment of Flexible Alternating-Current Transmission Systems (FACTS). FACTS devices can reduce the flows of heavily loaded lines, maintain the bus voltages at desired levels, and improve the stability of a power network. The Unified Power Flow Controller (UPFC) is a versatile FACTS device that can independently or simultaneously control the active power, the reactive power and the bus voltage; however, to achieve such functionality, it is very important to determine the optimal location of the UPFC device, with the appropriate parameter setting, in the power system. In this paper, a genetic algorithm (GA) method is applied to determine the optimal location of the UPFC device in a network for the enhancement of the power-system loadability and the minimization of the active power loss in the transmission line. To verify our approach, simulations were performed on the IEEE 14 Bus, 30 Bus, and 57 Bus test systems. The proposed work was implemented in the MATLAB platform.
Design Aspects of a New Reliable Torsional Switch with Excellent RF Response
Gogna, Rahul ; Jha, Mayuri ; Gaba, Gurjot Singh ; Singh, Paramdeep ;
Transactions on Electrical and Electronic Materials, volume 17, issue 1, 2016, Pages 7~12
DOI : 10.4313/TEEM.2016.17.1.7
This paper proposes a metal contact RF MEMS switch which utilizes a see-saw mechanism to acquire a switching action. The switch was built on a quartz substrate and involves vertical deflection of the beam under an applied actuation voltage of 5.46 volts over a signal line. The see-saw mechanism relieves much of the operation voltage required to actuate the switch. The switch has a stiff beam eliminating any stray mechanical forces. The switch has an excellent isolation of −90.9 dB (compared to − 58 dB in conventional designs ), the insertion of −0.2 dB, and a wide bandwidth of 88 GHz (compared to 40 GHz in conventional design ) making the switch suitable for wide band applications.
A Simplified Li-ion Battery SOC Estimating Method
Zhang, Xiaoqiang ; Wang, Xiaocheng ; Zhang, Weiping ; Lei, Geyang ;
Transactions on Electrical and Electronic Materials, volume 17, issue 1, 2016, Pages 13~17
DOI : 10.4313/TEEM.2016.17.1.13
The ampere-hour integral method and the open circuit voltage method are integrated via the extended Kalman filter method so as to overcome insufficiencies of the ampere-hour integral method and the open circuit voltage method for estimating battery SOC. The process noise covariance and the measurement noise covariance of the extended Kalman filter method are simplified based on the Thevenin equivalent circuit model, with a proposed simplified SOC estimating method. Verification of DST experiments indicated that the battery SOC estimating method is simple and feasible, and the estimated SOC error is no larger than 2%.
Effect of a Cu Buffer Layer on the Structural, Optical, and Electrical Properties of IGZO/Cu bi-layered Films
Moon, Hyun-Joo ; Gong, Tae-Kyung ; Kim, Daeil ; Choi, Dong-Hyuk ; Son, Dong-Il ;
Transactions on Electrical and Electronic Materials, volume 17, issue 1, 2016, Pages 18~20
DOI : 10.4313/TEEM.2016.17.1.18
Transparent and conducting IGZO thin films were deposited by RF magnetron sputtering on thin Cu coated glass substrates to investigate the effect of a Cu buffer layer on the structural, optical, and electrical film properties. Although X-ray diffraction (XRD) analysis revealed that both the IGZO single layer and IGZO/Cu bi-layered films were in the amorphous phase, the IGZO/Cu films showed a lower resistivity of 5.7×10
Ωcm due to the increased mobility and high carrier concentration. The decreased optical transmittance of the IGZO/Cu films was also attributed to a one order of magnitude higher carrier concentration than the IGZO films. From the observed results, the thin Cu layer is postulated to be an effective buffer film that can enhance the opto-electrical performance of the IGZO films in transparent thin film transistors.
Reduction of Heat Generation from Junction Box in 3 kW Photovoltaic Power Generation System
Yun, Jung-Hyun ; Sun, Ki-Ju ; Cheon, Min-Woo ;
Transactions on Electrical and Electronic Materials, volume 17, issue 1, 2016, Pages 21~24
DOI : 10.4313/TEEM.2016.17.1.21
A junction box used in a 3 kW photovoltaic power generation system plays a role in collecting and supplying the direct current voltage produced by photovoltaic modules to an inverter. It is also used for facilitating maintenance checks and protecting the module and inverter by keeping the voltage constant. As for the junction box, using it in a parallel connection creates a difference between the setup modules. In order to compensate, an inverse voltage diode is used. But the high-power created through the solar generator can be delivered to the inverter through the inverter regularly. Therefore, a component can break down due to excess heat. And consequently short circuits and electric leakage occurs. In this study, using a junction box that enabled the bypass of high electric power, it was possible to reduce heat generation by approximately 35℃ when compared to a standard junction box.
Investigation of Endurance Degradation in a CTF NOR Array Using Charge Pumping Methods
An, Ho-Myoung ; Kim, Byungcheul ;
Transactions on Electrical and Electronic Materials, volume 17, issue 1, 2016, Pages 25~28
DOI : 10.4313/TEEM.2016.17.1.25
We investigate the effect of interface states on the endurance of a charge trap flash (CTF) NOR array using charge pumping methods. The endurance test was completed from one cell selected randomly from 128 bit cells, where the memory window value after 10
program/erase (P/E) cycles decreased slightly from 2.2 V to 1.7 V. However, the memory window closure abruptly accelerated after 10
P/E cycles or more (i.e. 0.97 V or 0.7 V) due to a degraded programming speed. On the other hand, the interface trap density (Nit) gradually increased from 3.13×10
for the initial state to 4×10
P/E cycles. Over 10
P/E cycles, the Nit increased dramatically from 5.51×10
P/E cycles to 5.79×10
P/E cycles due to tunnel oxide damages. These results show good correlation between the interface traps and endurance degradation of CTF devices in actual flash cell arrays.
First-principles Predictions of Structures and Piezoelectric Properties of PbTiO
Kim, Min Chan ; Lee, Sang Goo ; Joh, Cheeyoung ; Seo, Hee Seon ;
Transactions on Electrical and Electronic Materials, volume 17, issue 1, 2016, Pages 29~32
DOI : 10.4313/TEEM.2016.17.1.29
Using the various exchange-correlation functionals, such as LDA, GGA-PBE, GGA-PBEsol and GGA-AM05 functionals, first principle studies were conducted to determine the structures of paraelectric and ferroelectric PbTiO
. Based on the structures determined by the various functionals, the piezoelectric properties of PbTiO
are predicted under the density-functional perturbation theory (DFPT). The present prediction with the various GGA functionals are closer to the experimental findings compared to the LDA values. The present DFT calculations using the GGA-PBEsol functional estimate the experimental data more reasonably than the conventional LDA and GGA fucntionals. The GGA-AM05 functional also predicts the experimental data as well as the GGA-PBEsol. The piezoelectric tensor calculated with PBEsol is relatively insensitive to pressure.
Effects of the Ag Layer Embedded in NIZO Layers as Transparent Conducting Electrodes for Liquid Crystal Displays
Oh, Byeong-Yun ; Heo, Gi-Seok ;
Transactions on Electrical and Electronic Materials, volume 17, issue 1, 2016, Pages 33~36
DOI : 10.4313/TEEM.2016.17.1.33
In the present work, a Ni-doped indium zinc oxide (NIZO) film and its multilayers with Ag layers were investigated as transparent conducting electrodes for liquid crystal display (LCD) applications, as a substitute for indium tin oxide (ITO) electrodes. By interposing the Ag layer between the NIZO layers, the loss of the optical transmittance occurred; however, the Ag layer brought enhancement of electrical sheet resistance to the NIZO/Ag/NIZO multilayer electrode. The twisted nematic cell based on the NIZO/Ag/NIZO multilayer electrode exhibited superior electro-optical characteristics than those based on single NIZO electrode and was competitive compared to those based on the conventional ITO electrode. An LCD-based NIZO/Ag/NIZO multilayer electrode may allow new approaches to conventional ITO electrodes in display technology.
Performance Enhancement of Organic Light-emitting Diodes with an Electron-transport Layer of Bathocuproine
Honga, Jin-Woong ; Guo, Yi-Wei ; Shin, Jong-Yeol ; Kim, Tae Wan ;
Transactions on Electrical and Electronic Materials, volume 17, issue 1, 2016, Pages 37~40
DOI : 10.4313/TEEM.2016.17.1.37
Performance enhancement of organic light-emitting diodes (OLEDs) is investigated in a device structure of ITO/TPD/Alq
/LiF/Al and ITO/TPD/Alq
/BCP/LiF/Al. Here, bathocuproine (BCP) is used as an electron-transport layer. Current density-voltage-luminance characteristics of the OLEDs show that the performance of the device is better with BCP layer than without BCP layer. The current density, luminance, luminous efficiency, and external-quantum efficiency are improved by approximately 22%, 50%, 2%, and 18%, respectively. Since the BCP layer lowers the electron energy barrier, electron transport is facilitated and the movement of hole is blocked as the applied voltage increases. This results in an increased recombination rate of holes and electrons.
Manufacturing of a Planar Lighting Device Using Cs
Sb Photocathode Emitters
Jeong, Hyo-Soo ;
Transactions on Electrical and Electronic Materials, volume 17, issue 1, 2016, Pages 41~45
DOI : 10.4313/TEEM.2016.17.1.41
Sb photocathode was formed by non-vacuum process technology and successive in-situ photocathode vacuum device fabrication carried out in a process chamber. Performance testing of the device was followed. Light emission from the devices was induced by photoemitted electrons, which were accelerated by an anode electric field that was shielded from the photoemitter surface. The luminescent characteristics of the devices were investigated by measuring the optical parameters as functions of the applied anode voltages. The results showed that this approach could produce a more easily directed and controlled stream of light. These features make these devices suitable for a variety of planar lighting applications.
Investigation of the Contact Resistance Between Amorphous Silicon-Zinc-Tin-Oxide Thin Film Transistors and Different Electrodes Using the Transmission Line Method
Lee, Byeong Hyeon ; Han, Sangmin ; Lee, Sang Yeol ;
Transactions on Electrical and Electronic Materials, volume 17, issue 1, 2016, Pages 46~49
DOI : 10.4313/TEEM.2016.17.1.46
A thin film transistor (TFT) has been fabricated using the amorphous 0.5 wt% Si doped zinc-tin-oxide (a-0.5 SZTO) with different electrodes made of either aluminium (Al) or titanium/aluminium(Ti/Al). Contact resistance and total channel resistance of a-0.5SZTO TFTs have been investigated and compared using the transmission line method (TLM). We measured the total resistance of 1.0×10
Ω/cm using Ti/Al electrodes. This result is due to Ti, which is a material known for its adhesion layer. We found that the Ti/Al electrode showed better contact characteristics between the channel and electrodes compared with that made of Al only. The former showed a less contact and total resistance. We achieved high performance of the TFTs characteristic, such as Vth of 2.6 V, field effect mobility of 20.1 cm
, S.S of 0.9 Vdecade
, and on/off current ratio of 9.7×10
A. It was demonstrated that the Ti/Al electrodes improved performance of TFTs due to enhanced contact resistance.
Performance of Non Punch-Through Trench Gate Field-Stop IGBT for Power Control System and Automotive Application
Kang, Ey Goo ;
Transactions on Electrical and Electronic Materials, volume 17, issue 1, 2016, Pages 50~55
DOI : 10.4313/TEEM.2016.17.1.50
In this paper, we have analyzed the electrical characteristics of 1200V trench gate field stop IGBT and have compared to NPT planar type IGBT and NPT planar field stop IGBT. As a result of analyzing, we obtained superior electrical characteristics of trench gate field stop IGBT than conventional IGBT. To begin with, the breakdown voltage characteristic was showed 1,460 V and on state voltage drop was showed 0.7 V. We obtained 3.5 V threshold voltage, too. To use these results, we have extracted optimal design and process parameter and designed trench gate field stop IGBT. The designed trench gate IGBT will use to inverter of renewable energy and automotive industry.