Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
The Transactions of The Korean Institute of Electrical Engineers
Journal Basic Information
Journal DOI :
The Korean Institute of Electrical Engineers
Editor in Chief :
Volume & Issues
Volume 62, Issue 12 - Dec 2013
Volume 62, Issue 11 - Nov 2013
Volume 62, Issue 10 - Oct 2013
Volume 62, Issue 9 - Sep 2013
Volume 62, Issue 8 - Aug 2013
Volume 62, Issue 7 - Jul 2013
Volume 62, Issue 6 - Jun 2013
Volume 62, Issue 5 - May 2013
Volume 62, Issue 4 - Apr 2013
Volume 62, Issue 3 - Mar 2013
Volume 62, Issue 2 - Feb 2013
Volume 62, Issue 1 - Jan 2013
Selecting the target year
DFT-based Power System Frequency Estimation using Two Digital Filters for Noise Effect Reduction
Hwang, Jin Kwon ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 891~897
DOI : 10.5370/KIEE.2013.62.7.891
The power system frequency plays an important role in monitoring and controlling the power system. The frequency can be measured through discrete Fourier transform (DFT) coefficients of its positive fundamental frequency. The accuracy of the frequency estimate is severely affected by noise in the power system signal and the leakage effect of the negative fundamental frequency in DFT. This paper proposes a DFT-based frequency estimation algorithm to cope with the noise as well as the leakage effect. In this algorithm, two suitable digital filters are introduced to reduce efficiently frequency estimate error due to the noise. These filters are designed to use a digital bandpass filter and a second-degree integrator. The effectiveness of the proposed algorithm in reduction of frequency estimate error is verified through simulations on noise, harmonics and frequency deviation.
Black Start and Synchronization of Microgrid Considering Distributed Generation Control
Choi, Jin-Young ; Won, Dong-Jun ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 898~904
DOI : 10.5370/KIEE.2013.62.7.898
In order to minimize the damage from power outage, power system should be restored quickly. In this paper, a procedure for the restoration of microgrid is proposed. After elimination of the causes of power outage, a black start algorithm is executed by considering the characteristics of distributed generation control. After all resources have been recovered to the normal state, a grid reconnecting algorithm for stable operation in grid-connected mode is performed. In order to verify the proposed algorithm, low voltage microgrid is simulated using PSCAD/EMTDC.
Analysis of Sequence Impedances of 345kV Cable Transmission Systems
Choi, Jong-Kee ; Ahn, Yong-Ho ; Yoon, Yong-Beum ; Oh, Sei-Ill ; Kwa, Yang-Ho ; Lee, Myoung-Hee ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 905~912
DOI : 10.5370/KIEE.2013.62.7.905
Power system fault analysis is commonly based on well-known symmetrical component method, which describes power system elements by positive, negative and zero sequence impedance. In case of balanced fault, such as three phase short circuit, transmission line can be represented by positive sequence impedance only. The majority of fault in transmission lines, however, is unbalanced fault, such as line-to-ground faults, so that both positive and zero sequence impedance is required for fault analysis. When unbalanced fault occurs, zero sequence current flows through earth and skywires in overhead transmission systems and through cable sheaths and earth in cable transmission systems. Since zero sequence current distribution between cable sheath and earth is dependent on both sheath bondings and grounding configurations, care must be taken to calculate zero sequence impedance of underground cable transmission lines. In this paper, conventional and EMTP-based sequence impedance calculation methods were described and applied to 345kV cable transmission systems (4 circuit, OF 2000mm2). Calculation results showed that detailed circuit analysis is desirable to avoid possible errors of sequence impedance calculation resulted from various configuration of cable sheath bonding and grounding in underground cable transmission systems.
A Study on the Damping Loads Prediction to prevent Harmonic Resonance during the Power System Restoration
Lee, Heung-Jae ; Yu, Won-Kun ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 913~917
DOI : 10.5370/KIEE.2013.62.7.913
During the restoration process of primary restorative transmission system, some over voltages may happen due to nonlinear interaction between unloaded transformers and transmission systems. These over voltages caused by harmonic resonance can be suppressed by inserting damping loads before energizing transformers. But it is very difficult to predict the occurrence possibility of harmonic resonance and complex simulation must be repeated to estimate the sufficient damping loads. This paper presents a damping loads prediction system to prevent harmonic resonance. Detailed analysis of the relationship between harmonic resonance and the amount of damping loads is discussed. The prediction system is developed using a curve fitting and a neural network based on this relationship. A curve fitting used a Gaussian function based on non-linear least square method and multi-layer back-propagation neural network is applied. The system is applied to primary restorative transmission lines in korean power system and the result showed satisfactory performance.
Virtual Inertial Control of a Wind Power Plant using the Maximum Rate of Change of Frequency
Kim, Dooyeon ; Kim, Jinho ; Lee, Jinshik ; Kim, Yeon-Hee ; Chun, Yeong-Han ; Kang, Yong Cheol ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 918~924
DOI : 10.5370/KIEE.2013.62.7.918
In a conventional power system, the frequency is recovered to the nominal value by the inertial, primary, and secondary responses of the synchronous generators (SGs) after a large disturbance such as a generator tripping. For a power system with high wind penetration, the system inertia is significantly reduced due to the maximum power point tracking control based operation of the variable speed wind generators (WGs). This paper proposes a virtual inertial control for a wind power plant (WPP) based on the maximum rate of change of frequency to release more kinetic energy stored in the WGs. The performance of the proposed algorithm is investigated in a model system, which consists of a doubly fed induction generator-based WPP and SGs using an EMTP-RV simulator. The results indicate that the proposed algorithm can improve the frequency nadir after a generator tripping. In addition, the algorithm can lead the instant of a frequency rebound and help frequency recovery after the frequency rebound.
Analysis on the Operation Characteristics and Protection Coordination between the Current Ratio Differential Relay for Line Protection and the Trigger-type SFCL in the Power Transmission System
Cho, Yong-Sun ; Kim, Jin-Seok ; Lim, Sung-Hun ; Kim, Jae-Chul ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 925~930
DOI : 10.5370/KIEE.2013.62.7.925
The fault current of the power transmission system is greater than that of the power distribution system. Therefore, the introduction of superconducting fault current limiter (SFCL) is more needed to reduce the increased fault current. The trigger-type SFCL consists of the high-temperature superconducting element (HTSC), the current limiting reactor (CLR) and the circuit breaker (CB). The trigger-type SFCL can be used to supplement the disadvantages of the resistive-type SFCL. The operation characteristics of the current ratio differential relay which is usually applied to the protection device of the power transmission system are expected to be affected under fault conditions and the applicability of the trigger-type SFCL. In this paper, we analyzed the operating characteristics, by the fault conditions, between the current ratio differential relay for line protection and the trigger-type SFCL in the power transmission system through the PSCAD/EMTDC simulation.
Temperature Characteristics Analysis of Hybrid Transformer
Kim, Jong-Wang ; Park, Hun-Yang ; Lee, Hyang-Beom ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 931~936
DOI : 10.5370/KIEE.2013.62.7.931
In this paper, the temperature distribution of 400kVA hybrid transformer is predicted by using CFD analysis. The copper loss and iron loss which are heat source are calculated by using Joule heat and Bertotti's equation respectively. To improve the convergence of the numerical calculation and to reduce the computation time, the 1/4 model is used and the incompressible air model is used for external air. To verify analysis result, the temperature rise test and no-load test of the transformer are performed. The experiment result obtained by using thermo-graphic camera is similar to the numerical result of the CFD analysis.
Study on Measurement Technology for Equivalent Series Impedance of High-voltage Pulsed Power Capacitors
Lee, Byeong-Yoon ; Lee, Byung-Ha ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 937~942
DOI : 10.5370/KIEE.2013.62.7.937
Equivalent series impedance of high-voltage pulsed power capacitor is one of the important electrical characteristics both for users and for capacitor manufacturers because it may have serious effects on the performance of pulse forming circuits. In this paper, definition of equivalent series impedance and factors which generate equivalent series impedance are reviewed. Theoretical analysis for the calculation of equivalent series impedance based on differential measurement method is described and calculation program has been developed. In order to acquire data which are necessary to calculate equivalent series impedance from discharging current waveform, charging-dischargig controller has been manufactured. Measurement results of equivalent series impedance for high voltage pulsed power capacitor have been given.
Control of the Bidirectional DC/DC Converter for a DC Distribution Power System in Electric Vehicles
Chang, Han-Sol ; Lee, Joon-Min ; Kim, Choon-Tack ; La, Jae-Du ; Kim, Young-Seok ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 943~949
DOI : 10.5370/KIEE.2013.62.7.943
Recently, an electric vehicle (EV) has been become a huge issue in the automotive industry. The EV has many electrical units: electric motors, batteries, converters, etc. The DC distribution power system (DPS) is essential for the EV. The DC DPS offers many advantages. However, multiple loads in the DC DPS may affect the severe instability on the DC bus voltage. Therefore, a voltage bus conditioner (VBC) may use the DC DPS. The VBC is used to mitigate the voltage transient on the bus. Thus, a suitable control technique should be selected for the VBC. In this research, Current controller with fixed switching frequency is designed and applied for the VBC. The DC DPS consist of both a resistor load and a boost converter load. The load variations cause the instability of the DC DPS. This instability is mitigated by the VBC. The simulation results by Matlab simulink and experimental results are presented for validating the proposed VBC and designed control technique.
A Novel Current Sensing Method for Low-Cost Vector-Controlled Inverter of AC Motor
Lee, Won-Il ; Yoon, Duck-Yong ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 950~955
DOI : 10.5370/KIEE.2013.62.7.950
This paper proposes a new low-cost current detection method to implement vector-controlled inverter of 3-phase induction motor or permanent-magnet synchronous motor using 2 shunt resistors instead of expensive Hall current sensors. The proposed method can detect perfect phase currents without current-immeasurable area in all operating conditions of motor. This method uses 2 shunt resistors in Hall current sensor positions conventionally used to detect phase currents. Therefore, it requires accurate analog differential amplifiers to detect voltages across shunt resistors at high electric potential to ground. We show the good solutions which are implemented by voltage-divider resistors networks and the instrumentation amplifiers using several Op Amps at cheap price. Computer simulations and experiments were performed to confirm the effectiveness of proposed method. These results show that proposed method can perfectly detect phase currents without current-immeasurable area in all operating conditions of motor.
Sensorless Speed Control of PMSM Based on Novel Adaptive Control with Compensated Parameters
Nam, Kee-Hyun ; Kwon, Young-Ahn ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 956~962
DOI : 10.5370/KIEE.2013.62.7.956
Recently, sensorless controls, which eliminate position and speed sensor in a permanent magnet synchronous motor drive, have been much studied. Most sensorless control algorithms are based on the back-EMF and speed estimations which are obtained from the voltage equations. Therefore, the sensorless control performance is largely affected by the parameter errors of a motor. This paper investigates a novel adaptive control with the parameter error compensation for the speed sensorless control of a permanent magnet synchronous motor. The proposed parameter estimation is obtained from the d-axis current error between the real and estimated currents. The proposed algorithm is verified through the simulation and experimentation.
Ionizing Radiation Sensitivity Analysis of the Structural Characteristic for the MOS Capacitors
Hwang, Young-Gwan ; Lee, Seung-Min ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 963~968
DOI : 10.5370/KIEE.2013.62.7.963
Ionizing Radiation effects on MOS devices provide useful information regarding the behavior of MOS based devices and circuits in the electronic instrumentation parts and instructive data for making the high sensitive sensors. The study presents the results of the analysis on the structural characteristics of MOS capacitor for sensing the ionizing radiation effect. We performed numerical modeling of Ionizing-radiation effect on MOS capacitor and simulation using Matlab program. Also we produced MOS capacitors and obtained useful data through radiation experiment to analyse the characteristic of ionizing radiation effect on MOS capacitor. Increasing the thickness of MOS capacitor's oxide layer enhanced the sensitivity of MOS capacitor under irradiation condition, but the sensitivity of irradiated MOS capacitor is uninfluenced by the area of MOS capacitor. The high frequency capacitance of the MOS capacitor is found to be strongly affected by incident ionizing radiation.
A Study on Implementation of a Transient Radiation Effects on Electronics(TREE) Assessment System Based on M&S
Lee, Nam-Ho ; Lee, Seung-Min ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 969~973
DOI : 10.5370/KIEE.2013.62.7.969
To simulate the effect of high dose-rate radiation on semiconductor devices, device modeling work has been performed especially in the area of photo-current generation by a PIN diode. The resultant analytical values were compared with experimental ones that were specially designed and performed to benchmark the simulation results. Initial results showed 27.85% error between the simulation and the experiment. The error can be further reduced by improvement both in simulation and in related experiments. The developed technique from the study can be applicable to radiation dosimetry and to analysis on the radiation effects in electronics.
Humidity Sensing Characteristics of TiO
Thin Films Fabricated by R.F.Sputtering Method
You, Do-Hyun ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 974~979
DOI : 10.5370/KIEE.2013.62.7.974
thin films are fabricated using R.F.sputtering method.
thin films are coated on
substrate printed IDE(interdigitated electrode). Impedance of thin films decreases according to increase relative humidity and it increases according to decrease measuring frequency. When substrate temperature is room temperature, impedance of thin films is from 45.68[MHz] to 37.76[MHz] within the limits from 30[%RH] to 75[%RH] at 1[kHz]. Whereas when substrate temperature is 100[
], impedance of thin films is from 692[kHz] to 539[kHz] within the limits from 30[%RH] to 75[%RH] at 1[kHz]. Impedance variation of thin films is bigger in low frequency regions than in high frequency regions. When substrate temperature is 100[
], impedance of thin films is lower than that of room temperature.
Numerical Study on the Discharge Characteristics of Cylindrical Discharge Devices
Seo, Jeong-Hyun ; Shin, Bhum-Jae ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 980~986
DOI : 10.5370/KIEE.2013.62.7.980
In this paper, the discharge characteristics of ac-type cylindrical discharge devices with diameters (D) in the
range have been investigated numerically. The cylindrical devices have much lower breakdown voltages compared to the coplanar electrode structures. The breakdown voltage of the cylindrical structures increases with the decrease of diameters in
range, however, the breakdown voltage decreases slightly with the decrease of diameters. Also, as the diameter gets smaller, the electron heating efficiency is greatly improved.
Instantaneous Frequency Estimation of the Gaussian Enveloped Linear Chirp Signal for Localizing the Faults of the Instrumental Cable in Nuclear Power Plant
Lee, Chun Ku ; Park, Jin Bae ; Yoon, Tae Sung ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 987~993
DOI : 10.5370/KIEE.2013.62.7.987
Integrity of the control and instrumental cables in nuclear power plant is important to maintain the stability of the nuclear power plants. In order to diagnose the integrity of the cables, the diagnostic methods based on reflectometry have been studied. The reflectometry is a non-destructive method and it is applicable to diagnose the live cables. We introduce a Gaussian enveloped linear chirp reflectometry to diagnose the cables in the nuclear power plants. In this paper, we estimate the instantaneous frequency of the Gaussian enveloped linear chirp signal by using the weighted robust least squares filtering to localize the impedance discontinuities in the class 1E instrumental cable.
The Fault Tolerant Evaluation Model due to the Periodic Automatic Fault Detection Function of the Safety-critical I&C Systems in the Nuclear Power Plants
Hur, Seop ; Kim, Dong-Hoon ; Choi, Jong-Gyun ; Kim, Chang-Hwoi ; Lee, Dong-Young ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 994~1002
DOI : 10.5370/KIEE.2013.62.7.994
This study suggests a generalized availability and safety evaluation model to evaluate the influences to the system's fault tolerant capabilities depending on automatic fault detection function such as the automatic periodic testings. The conventional evaluation model of automatic fault detection function deals only with the self diagnostics, and supposes that the fault detection coverage of self diagnostics is always constant. But all of the fault detection methods could be degraded. For example, the periodic surveillance test has the potential human errors or test equipment errors, the self diagnostics has the potential degradation of built-in logics, and the automatic periodic testing has the potential degradation of automatic test facilities. The suggested evaluation models have incorporated the loss or erroneous behaviors of the automatic fault detection methods. The availability and the safety of each module of the safety grade platform have been evaluated as they were applied the automatic periodic test methodology and the fault tolerant evaluation models. The availability and safety of the safety grade platform were improved when applied the automatic periodic testing. Especially the fault tolerant capability of the processor module with a weak self-diagnostics and the process parameter input modules were dramatically improved compared to the conventional cases. In addition, as a result of the safety evaluation of the digital reactor protection system, the system safety of the digital parts was improved about 4 times compared to the conventional cases.
Forward Adaptive Prediction on Modified Integer Transform Coefficients for Lossless Image Compression
Kim, Hui-Gyeong ; Yoo, Hoon ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 1003~1008
DOI : 10.5370/KIEE.2013.62.7.1003
This paper proposes a compression scheme based on the modified reversible integer transform (MRIT) and forward adaptive prediction for lossless image compression. JPEG XR is the newest image coding standard with high compression ratio and that composed of the Photo Core Transform (PCT) and backward adaptive prediction. To improve the efficiency and quality of compression, we substitutes the PCT and backward adaptive prediction for the modified reversible integer transform (MRIT) and forward adaptive prediction, respectively. Experimental results indicate that the proposed method are superior to the previous method of JPEG XR in terms of lossless compression efficiency and computational complexity.
Fiber-optic Goniometer to Measure Knee Joint Angle for the Diagnosis of Gait Disturbance
Kim, S.G. ; Shin, S.H. ; Jeon, D. ; Hong, S.H. ; Sim, H.I. ; Jang, K.W. ; Yoo, W.J. ; Lee, B. ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 1009~1013
DOI : 10.5370/KIEE.2013.62.7.1009
In this study, we developed a fiber-optic goniometer for the continuous measurement of knee joint angle which provides important medical information on Alzheimer's disease. The fiber-optic goniometer is composed of a light-emitting diode (LED), a plastic optical fiber (POF), and a voltage output photodiode (PD). As a sensing part of the fiber-optic goniometer, a unclad fiber with regular intervals of 1 mm was fabricated to improve efficiency of bending loss according to the angle variation of knee joint. The emitting light with a center wavelength of 470 nm from a LED is guided by a POF to the PD, the transmitted light is then attenuated by the bending loss inside the bent POF. The intensity variation of the light transmitted from the POF gives rise to a change in output voltage in the fiber-optic goniometer. Therefore, we measured the real-time output voltage of the proposed fiber-optic goniometer using the unclad fiber according to the knee joint angle. Through the repeated experiments, the fiber-optic goniometer shows that it has a reversibility and a wide measurable angle range.
Digital Fractional Order Low-pass Differentiators for Detecting Peaks of Surface EMG Signal
Lee, Jin ; Kim, Sung-Hwan ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 1014~1019
DOI : 10.5370/KIEE.2013.62.7.1014
Signal processing techniques based on fractional order calculus have been successfully applied in analyzing heavy-tailed non-Gaussian signals. It was found that the surface EMG signals from the muscles having nuero-muscular disease are best modeled by using the heavy-tailed non-gaussian random processes. In this regard, this paper describes an application of digital fractional order lowpass differentiators(FOLPD, weighted FOLPD) based on the fractional order calculus in detecting peaks of surface EMG signal. The performances of the FOLPD and WFOLPD are analyzed based on different filter length and varying MUAP wave shape from recorded and simulated surface EMG signals. As a results, the WFOLPD showed better SNR improving factors than the existing WLPD and to be more robust under the various surface EMG signals.
Estimation of PTT (Pulse Transit Time) by Multirate Filtering Analysis
Kim, Hyun-Tae ; Kim, Jeong-Hwan ; Kim, Kyeong-Seop ; Lee, Jae-Ho ; Lee, Jeong-Whan ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 1020~1026
DOI : 10.5370/KIEE.2013.62.7.1020
Multirate filtering process on the biological signals like Electrocardiogram (ECG) and Photoplethysmogram (PPG) can be defined as the digital signal processing algorithm in which the sampling rate varies to omit or interpolate the intermediate values between the sampled data. With this aim, we suggest a new multirate filtering algorithm by deleting the extraneous data to eliminate the unwanted degradations such as granular noise due to the usage of high sampling frequency and simultaneously to detect the fiducial features of ECG and PPG with reducing the complexity of resolving fiducial points such as R-peak, Pulse peak and Pulse Transit Time (PTT). After the experimental simulations performed, we can conclude the fact that we can detect the fiducial features of ECG and PPG signal in terms of R-peak, Pulse peak and PTT without the loss of accuracy even if we do not maintain the original sampling frequency.
Output Characterization Analysis of Induction Generator using Test Data
Kim, Jong-Gyeum ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 1027~1032
DOI : 10.5370/KIEE.2013.62.7.1027
Induction generator is used primarily in small hydroelectric power station less than 1000kW recently. Unlike the synchronous generator, induction generator produces electricity when it is rotated above synchronous speed. In this study, we calculated the parameters of the induction generator with test reports presented by the manufacturer and analyzed that how much the induction generator has produced power near the rated speed. If we can use the test data to calculate the parameters, it is possible the output characteristics analysis of the induction generator. As a result of analysis, we concluded that output of induction generator varies sensitively for small changes in rotational speed in the near synchronous speed.
Analysis of Transient Characteristics of a SFCL Applied Into Third-winding Transformer in a Single Line-to-ground Fault
Choi, Hye-Won ; Choi, Hyo-Sang ; Jung, Byung-Ik ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 1033~1037
DOI : 10.5370/KIEE.2013.62.7.1033
Coercion transformer is commonly used in the electrical grid which in three phase of distribution system. The accident of the electrical grid is divided into a single, a double, a third line-to-ground faults and a double, a third line-to-line faults. A single line-to-ground fault accounts for nearly 75[%] among them. In this research, when a Superconducting Fault Current Limiters (SFCL) was applied to the three phase power system, operation in a single line-to-ground fault and limiting characteristics of fault current according to turns ratio of third winding were analyzed. When a single line-to-ground fault happened, secondary winding's circuit was open. Then third winding's circuit with a SFCL was closed. So fault current was limited by diverted circuit. At this time, we could find out that size of the limited fault current could be changed according to third winding rate. We confirmed that limiting operation of the fault current was carried out within one-period. These results will be utilized in adjusting the size of the SFCL.
A Study on the Thermal Characteristics of 110kW-class IPMSM for Light Railway Transit using the 3-Dimensional Thermal Equivalent Network considering Heat Source by Iron Loss Density Distributions
Park, Chan-Bae ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 1038~1044
DOI : 10.5370/KIEE.2013.62.7.1038
A research on thermal analysis method is conducted for the characterization of heat generation during operation of Interior Permanent Magnet Synchronous Motor(IPMSM) for Light Railway Transits(LRT) in this paper. Efficient cooling of the heat generated in the IPMSM is important because the excessive heat generated from the winding, core and permanent magnet makes it harder for a long time continuous operation of IPMSM. Therefore, in order to analyze the heat generation characteristics of the 110kW-class IPMSM as advanced research for application the IPMSM to the cooling device, the heat transfer coefficients for each component of the 110 kW-class IPMSM were derived and the thermal equivalent network was configured to perform the thermal analysis in this study. Finally, the 110kW-class IPMSM prototype is made and a comparative verification between the test data and the thermal analysis results through its various performance tests are carried out.
A Study on the Design of the Flywheel Energy Storage Device to Store the Regenerative Energy
Lee, Jun-Ho ; Park, Chan-Bae ; Lee, Byeong-Song ;
The Transactions of The Korean Institute of Electrical Engineers, volume 62, issue 7, 2013, Pages 1045~1052
DOI : 10.5370/KIEE.2013.62.7.1045
In this study we deal with design procedures for the flywheel energy storage system that has the capacity to store the regenerative energy produced from the railway vehicles. The flywheel energy storage system (FESS) stores the regenerative electrical energy into the high speed rotational flywheel, by conversion the electrical energy into the mechanical rotational energy. Thus the FESS is composed of the energy conversion components, such as the motor and generator, mechanical support components, such as the rotational rotor, the magnetic bearings to support the rotor, and the digital controller to control the air gap between the rotor and the magnetic bearings. In this paper the design procedures for the rotor operating at the rigid mode and the magnetic bearings to support the rotational rotor without contact are presented.