권호 표지

전기학회논문지 (The Transactions of The Korean Institute of Electrical Engineers) (The Transactions of The Korean Institute of Electrical Engineers)

대한전기학회 (The Korean Institute of Electrical Engineers)

  • 월간
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  • 1975-8359(pISSN)
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  • 2287-4364(eISSN)

Aim & Scope

The first issue of The Transactions of the Korean Institute of Electrical Engineers(KIEE) was in October 1948. The Transactions of the KIEE is a monthly periodical published on the 1st day of each month. KIEE is an official publication of the Korean Institute of Electrical Engineers. The aim of the journal is to publish the highest quality manuscripts dedicated to the advancement of electrical engineering technologies. The Journal contains papers related to electrical power engineering, electrical machinery and energy conversion systems, electro-physics and application, information and controls, as well as electrical facilities. Currently, KIEE Transactions is divided into: “A” Sector (Power Engineering); “B” Sector (Electrical Machinery and Energy Conversion System); “C” Sector (Electro-physics and Application); “D” Sector (Information and Control); and “E” Sector (Electrical Facilities). With an aim to collect and publish outstanding scientific papers related to electrical engineering, the topics of papers published in KIEE Transactions are further divided into: power systems, transmission and distribution systems, electric power system economics, micro-grid, power system protection and automation, pumped-storage hydro power generation and electric energy storage systems in the “A” Sector; electrical equipment and appliances, power electronics, electrical traffic systems, new and renewable energy systems, eco-friendly electric power equipment, super-conductive equipment and E-mobility in the “B” Sector; electrical materials and semiconductors, smart large power and high voltage technology, optoelectronics and electromagnetic waves, Micro Electro Mechanical Systems (MEMS), and power asset risk management in the “C” Sector; instrumentation and control (I&C), robotics and automation, computer intelligence and intelligence systems, signal processing and embedded systems, autonomous moving object information processing, and biomedical engineering in the “D” Sector; and engineering and supervision, construction technology, power distribution system diagnosis, safety technology, electric railroad, technical standards, LVDC Facility, electric Facility fusion, etc. in the “E” Sector

http://www.trans.kiee.or.kr/ KSCI KCI SCOPUS

제65권9호

  1. 이형진;강병욱;허재선;김재철 1479
    https://doi.org/10.5370/KIEE.2016.65.9.1479 PDF KSCI
    This paper presents DC voltage recovery time improvement method in DC link of High Voltage Direct Current (HVDC) with offshore wind farm. The wind farm should be satisfied Low Voltage Ride Through(LVRT) control strategy when grid faults occur. The LVRT control strategy indicates actions which have to be executed according to the voltage dip ratio and the fault duration. However, The LVRT control strategy makes between wind farm and power system through DC Link voltage when grid fault occurs. The de-loading scheme is one of the method to control the DC voltage. But de-loading scheme need to long DC voltage recovery time. Thus, this paper proposes an improved de-loading scheme and we analysis DC voltage and active power reference through a simulation.
  2. 황혜미;박종배;이성희;노재형;박용기 1486
    https://doi.org/10.5370/KIEE.2016.65.9.1486 PDF KSCI
    This study presents the electrical load forecasting and error correction method using a real building load pattern, and the way to manage the energy storage system with forecasting results for economical load operation. To make a unique pattern of target load, we performed the Hierarchical clustering that is one of the data mining techniques, defined load pattern(group) and forecasted the demand load according to the clustering result of electrical load through the previous study. In this paper, we propose the new reference demand for improving a predictive accuracy of load demand forecasting. In addition we study an error correction method for response of load events in demand load forecasting, and verify the effects of proposed correction method through EMS scheduling simulation with load forecasting correction.
  3. 이대식;이강현 1493
    https://doi.org/10.5370/KIEE.2016.65.9.1493 PDF KSCI
    This paper proposes a system for reducing the standby power consumption in using the consumer electronic devices such as a television, a home theater, a set-top box, or a DVD player. The system is consisted of a flyback converter, monitoring circuits, a relay and a micro-processor. The proposed system can reduce the standby power consumption by disconnecting the AC input and the consumer devices can be turned on with a remote control. The proposed standby power system consumes the low power to receive the infrared signal from the remote controller. Furthermore, a electronic double layer capacitor is used to store the energy with high efficiency. The proposed power system can operate the 플라이백 converter to charge the electronic double layer capacitor and connect the AC input to the consumer electronic devices. The proposed power circuit can reduce the standby power consumption in AV devices without increasing the cost. The prototype is implemented to verify the system with the commercialized products.
  4. 한영재;조정민;이진호;김창현 1497
    https://doi.org/10.5370/KIEE.2016.65.9.1497 PDF KSCI
    This paper presents the overall measurement system for on-line test of super-speed maglev train. The super-speed maglev train is composed of vehicle, propulsion, power, and so on. In order to evaluate and diagnose for sub-system, we made overall measurement system. Just like the other measurement system, it is designed to distributed type. The hardware is consist of SCXI, PXI, Terminal, UPS, and so forth. It is installed on a train, control room, power room and track to collect lots of signals. The software controls hardware system, monitors main data such as inverter current, converter voltage. Using the measurement system, we evaluated a lot of performances for vehicle, track, and so forth. Through the developed system have improved reliability and safety for super-speed maglev train.
  5. 박재준 1504
    https://doi.org/10.5370/KIEE.2016.65.9.1504 PDF KSCI
    The aim of this study is to improve properties both glass transition temperature($T_g$) and coefficient of thermal expansion(CTE) using epoxy/micro-nano alumina composites with adding glycerol diglycidyl ether (GDE:1,2,3,5g). This paper deals with the effects of GDE addition for epoxy/micro alumina contents (40, 50, 60wt%)+surface modified nano alumina(1_phr) composites. 20 kinds specimen were prepared with containing micro, nano alumina and GDE as a micro composites(10, 20, 30, 40, 50, 60, 70wt%) or a nano/micro alumina composites(1phr/40, 50, 60wt%). Average particle size of nano and micro alumina used were 30nm and $1{\sim}2{\mu}m$, respectively. The micro alumina used were alpha phase with Heterogeneous and nano alumina were gamma phase particles of spherical shape. The glass transition temperature and coefficients of thermal expansion was evaluated by DSC and TMA. The glass transition temperature decreased and coefficients of thermal expansion become smaller with filled contents of epoxy/micro alumina composites. On the other hand, $T_g$ and CTE as GDE addition variation(1,2,3,5g) of epoxy/micro-nano alumina composites decreased and increased respectively.
  6. 박재준 1511
    https://doi.org/10.5370/KIEE.2016.65.9.1511 PDF KSCI
    The aim of this study is to improve of properties for electrical AC insulation breakdown strength using epoxy/micro-nano alumina composites with adding glycerol diglycidyl ether (GDE:1,3,5g). This paper deals with the effects of GDE addition for epoxy/micro alumina contents (40,50,60wt%)+surface modified nano alumina(1_phr) composites. 14 kinds specimen were prepared with containing epoxy resins, epoxy micro composites and epoxy nano-micro alumina mixture composites. Average particle size of nano and micro alumina used were 30nm and $1{\sim}2{\mu}m$, respectively. The micro alumina used were alpha phase with Heterogeneous and nano alumina were gamma phase particles of spherical shape. The electrical AC insulation breakdown strength was evaluated by sphere to sphere electrode system and raising velocity 1kV/s. The AC breakdown strength decreased insulation properties of multi-composites according to increasing micro alumina and GDE addition contents.
  7. 김정태;김우빈 1518
    https://doi.org/10.5370/KIEE.2016.65.9.1518 PDF KSCI
    In this study, in order to understand the degradation characteristics of oil-paper insulation for power transformers and OF cables, tan delta was measured using cable model specimens with long-term accelerated thermal and electrical aging. In addition, to find out the degradation level due to the accelerated aging, tensile strengths of aged papers were measured. As a result, tan ${\delta}$ showed the characteristics of slight decrease at the first stage and then increase with the aging time, which could be analyzed due to the evaporation of remaining moisture and the change of aging rate with time. Also, the trend of tensile strengths with aging temperature and time was appeared to be exponentially decreased and by use of these data equivalent calculated lifetimes and accelerated aging factors were derived for each aging temperatures. After then, tan ${\delta}$ was analyzed with the equivalent operating years. For all different aging temperatures, the aged data were very well fit to the equivalent operating years and it is shown that tan ${\delta}$ was increased with the decrease of tensile strength.
  8. 강형빈;문지현;이호재 1524
    https://doi.org/10.5370/KIEE.2016.65.9.1524 PDF KSCI
    This paper deals with a robust $H_{\infty}$ sampled-data controller design problem for nonlinear systems in Takagi-Sugeno fuzzy form with singular perturbation. The employed controller takes a state-feedback form. The design condition is represented in terms of linear matrix inequalities. A numerical examples is included to show the effectiveness of the theoretical development.
  9. 김선환;오성권 1531
    https://doi.org/10.5370/KIEE.2016.65.9.1531 PDF KSCI
    In this paper, we propose vehicle license plate recognition system based on Radial Basis Function Neural Networks (RBFNNs) with the use of local binarization functions and canny edge algorithm. In order to detect the area of license plate and also recognize license plate numbers, binary images are generated by using local binarization methods, which consider local brightness, and canny edge detection. The generated binary images provide information related to the size and the position of license plate. Additionally, image warping is used to compensate the distortion of images obtained from the side. After extracting license plate numbers, the dimensionality of number images is reduced through Principal Component Analysis (PCA) and is used as input variables to RBFNNs. Particle Swarm Optimization (PSO) algorithm is used to optimize a number of essential parameters needed to improve the accuracy of RBFNNs. Those optimized parameters include the number of clusters and the fuzzification coefficient used in the FCM algorithm, and the orders of polynomial of networks. Image data sets are obtained by changing the distance between stationary vehicle and camera and then used to evaluate the performance of the proposed system.
  10. 김은후;오성권;김현기 1541
    https://doi.org/10.5370/KIEE.2016.65.9.1541 PDF KSCI
    In this paper, we introduce a novel learning methodology of fuzzy clustering-based neural network pattern classifier. Fuzzy clustering-based neural network pattern classifier depicts the patterns of given classes using fuzzy rules and categorizes the patterns on unseen data through fuzzy rules. Least squares estimator(LSE) or weighted least squares estimator(WLSE) is typically used in order to estimate the coefficients of polynomial function, but this study proposes a novel coefficient estimate method which includes advantages of the existing methods. The premise part of fuzzy rule depicts input space as "If" clause of fuzzy rule through fuzzy c-means(FCM) clustering, while the consequent part of fuzzy rule denotes output space through polynomial function such as linear, quadratic and their coefficients are estimated by the proposed local least squares estimator(LLSE)-based learning. In order to evaluate the performance of the proposed pattern classifier, the variety of machine learning data sets are exploited in experiments and through the comparative analysis of performance, it provides that the proposed LLSE-based learning method is preferable when compared with the other learning methods conventionally used in previous literature.
  11. 조영완;김훈이;서기성 1551
    https://doi.org/10.5370/KIEE.2016.65.9.1551 PDF KSCI
    A combined CPG (Central Pattern Generator) based foot trajectory and GP (Genetic Programming) based joint compensation method is presented for the adaptive humanoid walking. The CPG based foot trajectory methods have been successfully applied to basic slops and variable slops with slow rates, but have a limitation for the steep slop terrains. In order to increase an adaptability of humanoid walking for the rough terrains, a GP based joint compensation method is proposed and combined to the CPG (Central Pattern Generator) based foot trajectory method. The experiments using humanoid robot Nao are conducted in an ODE based Webots simulation environmemt to verify a stability of walking for the various aslope terrains. The proposed method is compared to the previous CPG foot trajectory technique and shows better performances especially for the steep varied slopes.
  12. 마상용;홍상표;심현민;권장우;이상민 1557
    https://doi.org/10.5370/KIEE.2016.65.9.1557 PDF KSCI
    According to recent studies, poor sitting posture of the spine has been shown to lead to a variety of spinal disorders. For this reason, it is important to measure the sitting posture. We proposed a strategy for classification of sitting posture using machine learning. We retrieved acceleration data from single tri-axial accelerometer attached on the back of the subject's neck in 5-types of sitting posture. 6 subjects without any spinal disorder were participated in this experiment. Acceleration data were transformed to the feature vectors of principle component analysis. Support vector machine (SVM) and K-means clustering were used to classify sitting posture with the transformed feature vectors. To evaluate performance, we calculated the correct rate for each classification strategy. Although the correct rate of SVM in sitting back arch was lower than that of K-means clustering by 2.0%, SVM's correct rate was higher by 1.3%, 5.2%, 16.6%, 7.1% in a normal posture, sitting front arch, sitting cross-legged, sitting leaning right, respectively. In conclusion, the overall correction rates were 94.5% and 88.84% in SVM and K-means clustering respectively, which means that SVM have more advantage than K-means method for classification of sitting posture.
  13. 김영선;김동민;이기식 1564
    https://doi.org/10.5370/KIEE.2016.65.9.1564 PDF KSCI
    This study proposes a newly modified form of existing ground electrodes in order to secure trust of grounding system for large current caused by a stroke of lightning. Proposed planar earth structure has a several needle electrodes around a circular rod and 4 plane electrodes in all directions. The plane electrodes are fused with the insulator on the linear rod, so that they're electrically isolated. The concept is to increase the discharge amount of earth structure using multiple discharge paths like needle and plane electrodes. To check the discharge efficiency of the suggested scheme, the discharge currents are compared with typically used two kinds of ground rods. To ensure accuracy in the measurement of the discharge current, the same material was used for the comparison model. Also, the ground resistance are simulated by CDEGS commercial software and the results are compared with measured data. Based on this kind of experimental study, the suggested ground rod can be used when designing a ground system or when constructing a ground system at the site.
  14. 김영선;김동진;이기식 1571
    https://doi.org/10.5370/KIEE.2016.65.9.1571 PDF KSCI
    A Tesla coil is an electrical resonant transformer circuit invented by Nikola Tesla in 1891. It is used to produce high-voltage, low-current, high frequency alternating-current electricity. Tesla coil can generate a long streamer with several million volts of electricity as a high voltage device. It is basically consists of a voltage transformer, high voltage capacitor, spark gap, primary coil, secondary coil and toroid. It is difficult to appear in the output size of the streamer is controlled by the spark gap. The general decision method of the length of streamer is to display the electric output in accordance with the design specifications in initial development plan. Design specifications and the electric output is determined by the application of facilities. In this paper the spark gap is replaced with periodic switching semiconductor device to control output voltage easily in order to apply overvoltage protective circuit due to a secondary coil and a performance test. In these days, their main use is for entertainment and educational displays of the museum, although small coils are still used as leak detectors for high vacuum systems.
  15. 김준혁;김주락;김철환 1577
    https://doi.org/10.5370/KIEE.2016.65.9.1577 PDF KSCI
    Now we are facing severe environmental issues such as global warming. Due to these, the concerns about eco-friendly energy have been increased. Kyoto protocol and Copenhagen climate change conference are circumstantial evidence of it. With these trends, the interests for the Electric Vehicles(EVs) which do not emit any harmful gases have gradually been raised. Unfortunately, however, massive connection of EVs to the power system could cause negative impacts such as voltage variations, frequency variations and increase of demand power. To prevent the mentioned issues, KEPCO adopts Time-of-Use(ToU) price for EVs charging. Nevertheless, it is important to verify the propriety of the charging system. In this paper, therefore, we used pre-introduced price elasticity concept to predict possible Demand Response(DR) on charging of EVs. And analyzed possible demand power increase according to various price elasticities. Simulation results show that given ToU based charging system would not enough to control the increase of demand power by EVs on the power system. It is concluded, therefore, additional methods and/or algorithms are required.
  16. 전정채;김재진;최명일 1583
    https://doi.org/10.5370/KIEE.2016.65.9.1583 PDF KSCI
    This paper proposes an improved spread spectrum time domain reflectometry (ISSTDR) using time-frequency correlation and reference signal elimination method in order to have more accurate fault determination and location detection than conventional (SSTDR) despite increased signal attenuation due to the long distance to cable fault location. The proposed method has a two-step process: the first step is to detect a peak location of the reference signal using time-frequency correlation analysis, and the second step is to detect a peak location of the correlation coefficient of the reflected signal by removing the reference signal. The proposed method was validated through comparison with existing SSTDR methods in open-and short-circuit fault detection experiments of low voltage power cables. The experimental results showed that the proposed method can detect correlation coefficients at fault locations accurately despite reflected signal attenuation so that cable faults can be detected more accurately and clearly in comparison to existing methods.
  17. 조남희;오완식;김재문 1590
    https://doi.org/10.5370/KIEE.2016.65.9.1590 PDF KSCI
    In this paper, catenary wires were analyzed aging through the experiment about a new product and a test sample in accordance with temperature changes from long-term use. In case of the contact wire, the maximum load was reduced within 7% and the tensile strength showed a reduced within 6.7% compared with a new reference standard $110mm^2$. 19 Strands of messenger wire have a little more than a standard value, but result data on tensile test were less than the reference value about stranded wire. Also parts among 49 strands of dropper was found to be smaller than the reference value and it appeared greatly increasing intensity as toward the center of the strand.
  18. 윤용호 1597
    https://doi.org/10.5370/KIEE.2016.65.9.1597 PDF KSCI
    The speed at which the SRM (Switched Reluctance Motor) makes a transition from chopping control to single pulse operation. (i.e., low speed to high speed operation). It is unsatisfied with performance at all operational regimes. In this paper, the operational performance of SRM can be improved by using current hysteresis control method. This method maintains a generally flat current waveform. At the high speed, the current chopping capability is lost due to the development of the back-EMF. Therefore SRM operates in single pulse mode. By using zero-current switching and zero-voltage switching technique, the stress of power switches can be reduce in chopping mode. When the commutation from one phase winding to another phase winding, the current can be zero as fast as possible in this period because several times negative voltage of DC-source voltage produce in phase winding. This paper is compared to performance based on energy efficient C-dump converter topology and the proposed resonant C-dump converter topology. Simulation and experimental results are presented to verify the effectiveness of the proposed circuit.
  19. 박영;이기원 1605
    https://doi.org/10.5370/KIEE.2016.65.9.1605 PDF KSCI
    The measurement of current collection performance between pantograph and contact wire of overhead catenary system is intended to prove the safety of operation and the quality of the current collection system. The results of interaction performance of current collection system are required for approving with commercial operation on railway lines. The methods of interaction performance of current collection system are defined on interactional standards such as IEC 62486 and EN 50317. In this paper, the interaction performance is evaluated by the percentage of arcing on Honam high-speed line and the results are used for adjustment of the overhead catenary line structure. The experimental results in Honam high-speed line confirm that the duration of an arc lasting longer 25 ms between pantograph and contact wire was depended on the conditions of overhead contact line after installation.
  20. 허재행;김형철;신승권;박종영;김형익 1610
    https://doi.org/10.5370/KIEE.2016.65.9.1610 PDF KSCI
    To execute load curtailment efficiently for Urban Railway Load, the load patterns of the Urban Railway Load and available amount of load curtailment over the Urban Railway Load are analyzed through comparing the load to the common power loads. In addition, the current policies of the load curtailment for the Urban Railway Load are investigated and the problems of those are presented. Based on the researches, the optimal load curtailment strategies for the Urban Railway Load are proposed to minimize the consumer's utility diminishment and the costs of the use of energies. Finally, the optimal load curtailment strategies are applied to the real Urban Railway Load, the results shows that proposed methods are efficient and cost effective while the amount of load curtailment is minimized.
  21. 전희득;박한석;김대경;우경일 1618
    https://doi.org/10.5370/KIEE.2016.65.9.1618 PDF KSCI
    Electric motor systems account for more than half of all electric systems and the amount of energy consumption of those is almost 70 percent of total energy consumption of electric motor systems in industry. As electric motor systems are very responsible for global electricity savings and environment protection. Many international organizations are supporting standards and policy development processes to improve the efficiency of electric motor systems. Many standards are being developed at technical committee of IEC that has been required in order to support the implementation of efficiency regulations. High efficiency standards and levels for electric motor systems are slowly being introduced and compulsory in many countries. Therefore understanding the international efficiency evaluation standards and the regulation of electric motor systems of each country is important. This paper presents the current status and trends of international evaluation standards and regulations about the efficiency of electric motor systems.
  22. 김지명;김종겸 1626
    https://doi.org/10.5370/KIEE.2016.65.9.1626 PDF KSCI
    Generally, the low-voltage customer has been used with a linear load and nonlinear load in the 3-phase 4-wire distribution system. Linear load has usually configured the resistance and inductance, current phase is slower than the voltage phase, so power factor is low. It is required for the power factor correction device prior to the phase of the current than the voltage. The capacitor is connected in parallel to the load in order to ensure a low power factor. Power converter such as an inverter is a typical non-linear load. Non-linear load generates harmonic currents in the energy conversion process. Many electrical equipment may be adversely affected by the harmonic current. There, passive or active filter have been used to reduce these harmonics current. Passive filter consisting of inductor and capacitor generates a reactive power. According to the combination of filter inductor and capacitor, reactive power can be adjusted. In this paper, we analyzed how the combination of inductor and capacitor affects the overall power factor by simulation and measurement.