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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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The Transactions of The Korean Institute of Electrical Engineers
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The Korean Institute of Electrical Engineers
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Volume & Issues
Volume 63, Issue 12 - Dec 2014
Volume 63, Issue 11 - Nov 2014
Volume 63, Issue 10 - Oct 2014
Volume 63, Issue 9 - Sep 2014
Volume 63, Issue 8 - Aug 2014
Volume 63, Issue 7 - Jul 2014
Volume 63, Issue 6 - Jun 2014
Volume 63, Issue 5 - May 2014
Volume 63, Issue 4 - Apr 2014
Volume 63, Issue 3 - Mar 2014
Volume 63, Issue 2 - Feb 2014
Volume 63, Issue 1 - Jan 2014
Selecting the target year
Faulted Section Identification Method in The Distribution Systems with Renewable Energy Resources
Lee, Han-Seong ; Jeon, Cheol-Woo ; Kim, Young-Kook ; Lim, Seong-Il ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1321~1327
DOI : 10.5370/KIEE.2014.63.10.1321
Faulted section identification is one of the most important function in distribution automation systems. Conventional over current detection based fault indicators frequently mal-operate due to the reverse fault current from the renewable energy resources. This paper present a new faulted section identification method based on the fuzzy decision making technique. In order to establish feasibility of the proposed method, case studies using Matlab Simulink has been performed.
Development of Power System Health Algorithm
Lim, Jin-Taek ; Lee, Sung-Hun ; Lee, Yeon-Chan ; Choi, Jae-Seok ; Choi, Hong-Seok ; Joo, Joon-Young ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1328~1336
DOI : 10.5370/KIEE.2014.63.10.1328
This paper proposes Power System Health Index(PSHI) newly. The paper describes several kind of power system health indices based on two main categories, which are adequacy and security. In adequacy, four kinds of health indices of Frequency, Voltage, Reserve(Operating Reserve Power and Frequency Regulation Reserve Power) and Overload of lines and transformers are proposed. In security, four kinds of health indices of Voltage(154kV, 345kV and 765kV), Overload of lines and transformers, Power flow constraint among areas and SPS are proposed. All indices are mapped with three domains, which are indicated as Health, Margin and Risk, defined with expert interview. While domains of health, margin and risk is defined similar with the conventional well being analysis of power system. The criterion of the domains is proposed using an interview with expert operators and practical reliability codes in Korea. The several kinds of health index functions, which are linear ratio, piecewise linear ration and reverse ratio function etc. are developed in this paper. It will be expected that the developed health indices can help operators to control power system more successfully and also prevent power system from accident as like as black out in future because operator can make a decision immediately based on more easily visual information of system conditions from too much indices acquisition of complex power system.
Writing System of the Open Korean Knowledge Dictionary for Standardization of Smart grid Terminologies
Hwang, Humor ; Kim, Jung-Hoon ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1337~1346
DOI : 10.5370/KIEE.2014.63.10.1337
Power system technologies in the area of smart grid are being converged with communication system technologies or information technologies(IT). This interdisciplinary action affects on two parts vigorously so that IT has become a essential part of power industry. But terminologies of two parts are confused and it is necessary that these are standardized to develop the industry. The writing system of the Open Korean Knowledge Dictionary for standardization of smart grid terminologies which are IEC TC 57 glossary and non-glossary is proposed. The writing system includes the process of collection, writing guideline and standardization of terminologies. Writing results of 90,000 terminologies for electricity, communication and computer fields including smart grid terminologies, which are registered in the Open Korean Knowledge Dictionary, are shown. The system provides the capability of collection and delivery of academic society opinions for the selected and interpreted terminologies through the internet for standardization and industry propagation of smart grid terminologies.
Modeling and Experiment of 50kW Diesel Generator in Grid-connected Mode
Lee, Wujong ; Lee, Hak Ju ; Chag, Hanju ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1347~1353
DOI : 10.5370/KIEE.2014.63.10.1347
This paper researches a modeling and experiment of 50kW diesel generator in grid-connected mode. The output of diesel generator can be calculated by the phase difference between voltage and current as well as the diesel generator parameter such as mutual impedance, field current and rotor angle. Considering the different d-q frame impedance, the output of diesel generator is analyzed for equation and verified by simulation. The diesel generator modeled by considering the time delay for actuator, diesel engine and exciter. The controller of diesel generator is divided into governor and exciter. The governor consists of speed controller and active power controller, where speed controller maintains frequency as 60Hz and active power tracks active power reference. On the other hand, the exciter consists of voltage controller and reactive power controller, where voltage controller controls
and reactive power is controlled as zero. When the active power reference is changed as 0.1pu in the grid connected mode, the active power takes 10 seconds to reach the steady state and the reactive power is maintains as zero. The 50kW diesel generator is tested and experiment results are well matched with the simulation results.
An Improved Algorithm of Fault Indicator Generation of FRTU in Distribution Automation System
Seo, Jung-Soo ; Kim, Hyung-Seung ; Lim, Seong-Il ; Choi, Myeon-Song ; Lee, Seung-Jae ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1354~1363
DOI : 10.5370/KIEE.2014.63.10.1354
In this paper, an improved method of fault indicator generation algorithm in FRTUs is proposed for the present Distribution Automation System. In order to find fault area, correct FI information should be generated. But when a single line-to-ground fault occurs, FI information is generated in downside of the fault in some circumstance because existing FI algorithm considers only magnitude. It is found that the upside fault current direction if different from the downside fault current direction. Therefore, in order to prevent to generate the wrong fault indication information for FRTU at the downside of the fault, an improved fault indication generation method is developed. Not only the basic conditions are taken into account, but also the directions from the angle difference between zero and positive sequence currents are considered to generated the fault indication information. In case study, the proposed method has been testified and shown the reasonability in generating correct the fault indication information, for many kinds of faults according to conditions.
Development and Application of Pre/Post-processor to EMTP for Sequence Impedance Analysis of Underground Transmission Cables
Choi, Jong-Kee ; Jang, Byung-Tae ; An, Yong-Ho ; Choi, Sang-Kyu ; Lee, Myoung-Hee ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1364~1370
DOI : 10.5370/KIEE.2014.63.10.1364
Power system fault analysis has been based on symmetrical component method, which describes power system elements by positive, negative and zero sequence impedance. Obtaining accurate line impedances as possible are very important for estimating fault current magnitude and setting distance relay accurately. Especially, accurate calculation of zero sequence impedance is important because most of transmission line faults are line-to-ground faults, not balanced three-phase fault. Since KEPCO has started measuring of transmission line impedance at 2005, it has been revealed that the measured and calculated line impedances are well agreed within reasonable accuracy. In case of underground transmission lines, however, large discrepancies in zero sequence impedance were observed occasionally. Since zero sequence impedance is an important input data for distance relay to locate faulted point correctly, it is urgently required to analyze, detect and consider countermeasures to the source of these discrepancies. In this paper, development of pre/post processor to ATP (Alternative Transient Program) version of EMTP (Electro-Magnetic Transient Program) for sequence impedance calculation was described. With the developed processor ATP-cable, effects of ground resistance and ECC (Earth Continuity Conductor) on sequence impedance were analyzed.
Design and Drive Characteristics of Low Voltage 8/6 SRM for Fan Application
Ahn, Jin-Woo ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1371~1376
DOI : 10.5370/KIEE.2014.63.10.1371
In this paper, 4-phase switched reluctance motor(SRM) with 8-stator and 6-rotor pole structure is proposed for a high speed fan with a low voltage. The air blower has unidirectional rotation characteristics and requires a low torque ripple and noise as well as high efficiency. To achieve the requirements, voltage and current according to loading condition of limited specification is considered. Design process is to select the bore diameter, pole arc, york of stator and rotor to get a high torque and efficiency. To verify the validity of the proposed structure, finite element method(FEM) is employed to get the performances. And the converter for the proposed SRM is employed a 1.5q power converter for cost effectiveness. Prototype SRM is manufactured and tested, and the test results show this design is within the specification and good for the air blower applications.
Eddy Current Loss Analysis in Radial Flux Type Synchronous Permanent Magnet Coupling using Space Harmonic Methods
Min, Kyoung-Chul ; Kang, Han-Bit ; Park, Min-Gyu ; Cho, Han-Wook ; Choi, Jang-Young ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1377~1383
DOI : 10.5370/KIEE.2014.63.10.1377
This paper deals with eddy current loss of magnetic coupling with radial permanent magnet (PM) using analytical method such as a space harmonic method. Superposition of two kinds analysis model is used to analyze eddy current loss induced in inner PM and outer PM of magnetic coupling. When the eddy current is induced, the environmental temperature increases, and the permanent magnet(PM) characteristics are degraded because the performance of PM is greatly influenced by temperature rise. Hence, the calculation of eddy current loss becomes an important factor in the magnetic coupling. In order to analyze eddy current loss, first, on the basis of the magnetic vector potential and two-dimensional(2-D) polar-coordinate system, the magnetic field solutions of the radial magnetized PM are obtained. And we obtain the analytical solutions for the eddy current density produced by permanent magnet. Lastly, analytical solutions for eddy current loss are derived by using equivalent, electrical resistance calculated from magnet volume and analytical solution for eddy current density. This analytical results are validated by comparing with the 2-D finite element analysis (FEA).
Torque Ripple Minimization for Switched Reluctance Motors Using a Fuzzy Logic and Sliding Mode Control
Yoon, Jae-Seung ; Kim, Dong-Hee ; Shin, Hye-Ung ; Lee, Kyo-Beum ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1384~1392
DOI : 10.5370/KIEE.2014.63.10.1384
This paper presents a torque ripple reduction algorithm for the switched reluctance motor drives using the fuzzy logic and the sliding mode control. A turn-on angle controller based on the fuzzy logic determines the optimal turn-on angle. In addition, a sliding mode torque control (SMTC) methods reduces torque ripples instantaneously in the commutation region. The proposed algorithm does not require complex system models considering nonlinear magnetizing or demagnetizing periods of the phase current. According to the rotor speed and torque, the proposed controller changes the turn-on angle and reference torque instantaneously until the torque ripples are minimized. The simulation and experimental results verify the validity of minimizing the torque ripple performance.
Real-time Operation Analysis for Stand-alone Microgrid using RTDS
Lee, Yoon-Seok ; Han, Byung-Moon ; Won, Dong-Jun ; Lee, Hak Ju ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1393~1401
DOI : 10.5370/KIEE.2014.63.10.1393
In this paper the operational characteristics of stand-alone microgrid was analyzed using RTDS simulation models. The accuracy of developed simulation models were verified by comparing with the analysis results using the PSCAD/EMTDC simulation models. The proper scenarios and operation algorithms were developed and analyzed in accordance with various situations that can occur in the actual system, so as to establish operation scheme for the stand-alone microgrid system. The developed simulation models can be effectively utilized to design a newly installed stand-alone microgrid and to develop various operation scenarios for stand-alone microgrid. And these models can be applied for analyzing the transient phenomena due to system fault so that system protection can be properly designed.
The MPPT Control of a Small Wind Power Generation System by Adjusting the DC-Link Voltage of a Grid-connected Inverter
Park, Min-Gi ; Lee, Joon-Min ; Hong, Ju-Hoon ; Kim, Young-Seok ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1402~1411
DOI : 10.5370/KIEE.2014.63.10.1402
In this paper, the Maximum Power Point Tracking(MPPT) control of the small scale wind power generation system with a three-phase diode rectifier and the grid-connected inverter is studied. Without the need for the converter circuits to control speed of the generator, it is economical and the structure is simple. Compared with existing systems, it can be to reduce the power semiconductor switches and passive elements, and to implement the MPPT control with only DC-Link voltage control of the grid-connected inverter. In order to allow MPPT control without the characteristic information of the wind turbine, the P&O algorithm is applied, and these are verified by the simulation and experiment.
Plasma-polymerized Styrene Prganic thin Film as Hybrid OLEDs Encapsulation
Jung, Kun-Soo ; Lee, Boong-Joo ; Shin, Paik-Kyun ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1412~1416
DOI : 10.5370/KIEE.2014.63.10.1412
We report thin-film organic moisture barriers based on polystyrene(PS) laminates deposition by PECVD for an encapsulation of OLEDs. The organic polystyrene thin-film has the benzene ring structure and high hydrophobic characteristics and it was polymerized by PECVD in dry process. Life time properties of Ca test were obtained 32 minutes at the RF 100W process conditions. From the AFM test, the roughness of multi-layer thin-film was more excellent rather than that of a single-layer thin-film. In addition, 5 layers of the multi-layer film properties were obtained 45 minutes. So that the optical and electrical properties were not affected with these plasma polymerized organic thin-film encapsulation. For life time improvement, the inorganic
thin-film were deposited 5nm using ALD atomic layer deposition. The WVTR(Water Vaper Transmission Rate) value of hybrid thin-film encapsulation in the optimum process conditions was resulted by less than
. From the results of experiment, plasma polymerized hybrid encapsulation was suggested as the flexible display applications.
Analysis of DC Plasma using Electrostatic Probe and Fluid Simulation
Son, Eui-Jeong ; Kim, Dong-Hyun ; Lee, Ho-Jun ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1417~1422
DOI : 10.5370/KIEE.2014.63.10.1417
Using a parallel plate DC plasma system was prepared. Using this equipment, we investigated the basic discharge characteristics of DC argon plasma in terms of electron density, temperature, voltage and current waveforms and plasma potential. The effects of the electrode gap distance, input voltage, ballast resistance and pressure were measured using electrostatic probe. Plasma simulation using fluid approximation has been performed. External circuit effects was included in the simulation. Measured and calculated current voltage characteristics show similar tendencies.
Design of Generation Efficiency Fuzzy Prediction Model using Solar Power Element Data
Cha, Wang-Cheol ; Park, Joung-Ho ; Cho, Uk-Rae ; Kim, Jae-Chul ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1423~1427
DOI : 10.5370/KIEE.2014.63.10.1423
Quantity of the solar power generation is heavily influenced by weather. In other words, due to difference in insolation, different quantity may be generated. However, it does not mean all areas with identical insolation produces same quantity because of various environmental aspects. Additionally, geographic factors such as altitude, height of plant may have an impact on the quantity. Hence, through this research, we designed a system to predict efficiency of the solar power generation system by applying insolation, weather factor such as duration of sunshine, cloudiness parameter and location. By applying insolation, weather data that are collected from various places, we established a system that fits with our nation. Apart from, we produced a geographic model equation through utilizing generated data installed nationwide. To design a prediction model that integrates two factors, we apply fuzzy algorithm, and validate the performance of system by establishing simulation system.
Formation Control Algorithm for Swarm Robots Using Virtual Force
Tak, Myung Hwan ; Joo, Young Hoon ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1428~1433
DOI : 10.5370/KIEE.2014.63.10.1428
In this paper, we propose the formation control algorithm using the leader-following robots in given space. The proposed method is as follows: First, we plan a path of the leader robot for the obstacle avoidance. After that, we propose the formation control algorithm of the following robots using the position and the orientation angle of the leader robot. Also, we propose method for adjusting the formation of the swarm robots when the following robots detect an obstacles. Finally, we show the effectiveness and feasibility of the proposed method though some simulations.
Demosaicking of Hexagonally-Structured Bayer Color Filter Array
Lee, Kyungme ; Yoo, Hoon ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1434~1440
DOI : 10.5370/KIEE.2014.63.10.1434
This paper describes a demosaicking method for hexagonally-structured color filter array. Demosaicking is essential to acquire color images using color filter array (CFA) in single sensor imaging. Thus, CFA patterns have been discussed in order to improve image quality in single sensor imaging after the Bayer pattern are introduced. Advancements in imaging sensor technology recently introduce a hexagonal CFA pattern. The hexagonal CFA can be considered to be a 45-degree rotational version of the Bayer pattern, thus demosaicking can be implemented by an existing method with backward and forward 45-degree rotations. However, this approach requires heavy computing power and memory in image sensing devices because of the image rotations. To overcome this problem, we proposes a demosaicking method for a hexagonal Bayer CFA without rotations. In addition, we introduce a weighting parameter in our demosaicking method to improve image quality and to unifying exiting method with our method. Experimental results indicate that the proposed method is superior to conventional methods in terms of PSNR. In addition, some optimized values for the weighting parameter are provided experimentally.
A assessment of multiscale-based peak detection algorithm using MIT/BIH Arrhythmia Database
Park, Hee-Jung ; Lee, Young-Jae ; Lee, Jae-Ho ; Lim, Min-Gyu ; Kim, Kyung-Nam ; Kang, Seung-Jin ; Lee, Jeong-Whan ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1441~1447
DOI : 10.5370/KIEE.2014.63.10.1441
A robust new algorithm for R wave detection named for Multiscale-based Peak Detection(MSPD) is assessed in this paper using MIT/BIH Arrhythmia Database. MSPD algorithm is based on a matrix composed of local maximum and find R peaks using result of standard deviation in the matrix. Furthermore, By reducing needless procedure of proposed algorithm, improve algorithm ability to detect R peak efficiently. And algorithm performance is assessed according to detection rates about various arrhythmia database.
Study of the Wearable Electrocardiogram Measuring System using Capacitive-coupled Electrode
Lee, Jae-Ho ; Lee, Young-Jae ; Lee, Kang-Hwi ; Kang, Seng-Jin ; Kim, Kyeung-Nam ; Park, Hee-Jung ; Lee, Jeong-Whan ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1448~1454
DOI : 10.5370/KIEE.2014.63.10.1448
In this study, a new type of electrode device is implemented to measure the capacitance energy and interpret it as the ECG (Electrocardiogram) data. The main idea of this new electrode system is to estimate the capacitance on the skin by assembling a capacitive-coupled circuits and translate into the ECG signal. To measure the coupling energy and estimate the aquired data in terms of heart activity, the capacitive-coupled electrode is garmented with fabrics in the form of a chest band or a vest jacket. To compare the ECG data from the capacitive-coupled electrode with the conventional electrode(Ag-AgCl) system, the corelation coefficient between two signals is computed as 0.9517. Thus, we can conclude the fact that capacitive-coupled electrode system can measure a person's heart activity without any contact to his or her skin and can the interpreted as the ECG data.
A Sensitivity and Performance Analysis for Torque Mode Switching on 2MW Direct Drive Wind Turbine Generator
Rho, Joo-Hyun ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1455~1460
DOI : 10.5370/KIEE.2014.63.10.1455
Wind turbine generators were designed on general regulations of wind condition. At real situations, it could be different from the design conditions. There are many control methods and definitions of transient region, because an efficient wind turbine generator control logic is the important matter in generator performance and annual energy production at real conditions. In this document, the power generation sensitivity for wind speed and turbulence intensities was defined to know the sensitive transient region. Wind conditions are applied for the ranges of 7~10m/s mean wind speed and 14~20% turbulence intensity. The sensibility of HR-D86 wind generator was increased in transient region(8~10m/s) on power curve diagram through a torque control to a pitch control. And then GH-bladed simulations was performed for performance analysis of the torque mode switching in transient region on 2MW direct drive wind generator(HR-D86) which is designed IEC class II for onshore. Through the sensitivity and performance analysis, the sensitivity for real wind condition could be the performance index for an wind generator. And the torque mode switching in transient region can increase the mean power generation on HR-D86 wind turbine generator.
Performance Verification and Improvement of UHF Sensor for the Increasement of the Partial Discharge Detection Reliability
Kim, Won-Gyu ; Kim, Min-Soo ; Baek, Young-Sik ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1461~1466
DOI : 10.5370/KIEE.2014.63.10.1461
GIS(Gas Insulated Switchgear) is important power apparatus which have strong dielectric strength, supply electric power and is a part of the power system. Most substation type is configured as GIS. Recently, because of continuous increasement of GIS demand resulted from high quality & big capacity of electric power, the necessity of the preventive & diagnosis system is being expanded gradually. GIS partial discharge occurred on the UHF band is detected effectively by the method to IEC 60270 that recommend to be able to detect the apparent minimum discharge, 5 pC. Additionally, the UHF sensor should be installed to detect PD signal if Partial discharge signal, 5 pC occur in every part of GIS. Currently PD diagnosis system applying UHF sensor for GIS with various voltage level like 154 kV, 345 kV, 765 kV have been operated. And it is necessary to measure and analyze insulation breakdown phenomenon of inside GIS exactly. In this paper, we proposed Fat-dipole patch UHF sensor that is developed and more sensitive, excellent wide-range characteristic than the exising UHF sensor. And we performed KERI (Korea Electrotechnology Research Institute) reference test, which showed the excellent result for the all tests.
A Study on Powering Characteristic on Speed Variation of Propulsion System of Prototype 8200 Electric Locomotive
Jung, No-Geon ; Chang, Chin-Young ; Yun, Cha-Jung ; Kim, Jae-Moon ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1467~1472
DOI : 10.5370/KIEE.2014.63.10.1467
This paper study on powering characteristic on speed variation of propulsion system of prototype 8200 electric locomotive propulsion system through simulation modeling. For this purpose, it being applied in the field of railway IGBT (Insulated Gate Bipolar Transistor) elements are used. Converter was performed PLL (Phase-Locked Loop) control method that is used to control the phase and output voltage, and the inverter was carried an indirect vector control method to control the speed of traction motor. The results of simulation by modeling and experimental unit, we was confirmed that converter is controlled a unity power factor and output voltage by reference voltage. Also traction motor was controlled by indirect vector control and SVPWM inverter switching method very well.
Design and Thrust Force Measurement of LSM for High-Speed Maglev Train
Oh, Se-Young ; Lee, Chang-Young ; Lee, Ju ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1473~1478
DOI : 10.5370/KIEE.2014.63.10.1473
This paper deals with design and thrust force measurement of EMS type LSM for propulsion of the high-speed maglev train. The load of maglev train is calculated, and the design equations of the LSM are presented, and the LSM which is suitable for the operation of short-distance test track is designed. In addition, the finite element analysis is performed to confirm the back-EMF and thrust force characteristics of the LSM designed model. A short length LSM prototype model is manufactured. Finally, the thrust force of the LSM is measured by the method applying dc current to the stator winding instead of three-phase ac current. And the validity of the design and analysis is verified by this measurement.
Analysis of Utilizing Regenerative Energy in Railway System through a DC Power Supply Simulation
Shin, Seungkwon ; Jung, Hosung ; Kim, Hyungchul ; Park, Jongyoung ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1479~1484
DOI : 10.5370/KIEE.2014.63.10.1479
This paper deals with regenerative energy in railway system which one of the largest customer in terms of load capability. Unlike the other loads of power system, loads of railway systems change in time and space. It has a characteristic amount of generating regenerative energy by frequent starting and braking in railway system. Therefore, it is expected higher utilization in railway system than the other systems. The purpose of DC power supply simulation is analyzing backed energy, regenerative energy by each railway vehicle and substation. In this paper, regenerative energy utilization are analyzed using DC power supply simulation and it is performed changing major influence on the design such as the number of installing absorber, internal resistance value, no-load voltage value at substation or operating parameters at regenerative energy utilization. After simulating, results are compared and analyzed.
The Analysis of DC Plasmas Characteristics on SFSF
So, Soon-Youl ;
The Transactions of The Korean Institute of Electrical Engineers, volume 63, issue 10, 2014, Pages 1485~1490
DOI : 10.5370/KIEE.2014.63.10.1485
gas has been used for power transformers or gas insulated switchgears, because it has the superior insulation property and the stable structure chemically. It has been, however, one of global warming gases and required to reduce the its amount. Some papers have reported that its amount could be reduced by mixing with other gases, such as
and their mixture gases would cause the synergy effect. In this paper, we investigated the characteristics of DC plasmas on
mixture gases with
at atmospheric pressure.
gas is one of cheap gases and has been reported to show the synergy effect with mixing
gas, even though
plasmas have electron-positive characteristics. 38 kinds of
plasma particles, which consisted of an electron, two positive ions, five negative ions, 30 excitation and vibration particles, were considered in a one dimensional fluid simulation model with capacitively coupled plasma chamber. The results showed that the joule heating of
plasmas was mainly caused by positive ions, on the other hand electrons acted on holding the
plasmas stably. The joule heating was strongly generated near the electrodes, which caused the increase of neutral gas temperature within the chamber. The more
mixed-ratio increased, the less joule heating was. And the power consumptions by electron and positive ions increased with the increase of