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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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Journal DOI :
The Korean Institute of Electrical Engineers
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Volume & Issues
Volume 59, Issue 12 - Dec 2010
Volume 59, Issue 11 - Nov 2010
Volume 59, Issue 10 - Oct 2010
Volume 59, Issue 9 - Sep 2010
Volume 59, Issue 8 - Aug 2010
Volume 59, Issue 7 - Jul 2010
Volume 59, Issue 6 - Jun 2010
Volume 59, Issue 5 - May 2010
Volume 59, Issue 4 - Apr 2010
Volume 59, Issue 3 - Mar 2010
Volume 59, Issue 2 - Feb 2010
Volume 59, Issue 1 - Jan 2010
Selecting the target year
Securing Operation Margin Capacity as Coordination Control among the Power Compensation Equipments
Lee, Sang-Deok ; Baek, Young-Sik ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1011~1016
It is an important issue to electric power system operations that it can reliably supply large-capacity power to consumption area as due to increasing power demand growth. For this purpose, The FACTS equipment based on Power IT technology with the existing mechanical compensators has been applied to power system. Therefore we suggest on this paper that a plan for coordination control of multiple power compensation equipment in order to increase the utilization of each facility and secure operation margin capacity. As the result of simulation, it is possible to cope actively with a suddenly changed power system. This helps greatly for the voltage stability and supply reliability in a suddenly changed power system.
Available Transfer Capability Evaluation Considering CO
Emissions Using Multi-Objective Particle Swarm Optimization
Chyun, Yi-Kyung ; Kim, Mun-Kyeom ; Lyu, Jae-Kun ; Park, Jong-Keun ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1017~1024
Under the Kyoto Protocol many countries have been requested to participate in emissions trading with the assigned
emissions. In this environment, it is inevitable to change the system and market operation in deregulated power systems, and then ensuring safety margin is becoming more important for balancing system security, economy and
emissions. Nowadays, available transfer capability (ATC) is a key index of the remaining capability of a transmission system for future transactions. This paper presents a novel approach to the ATC evaluation with
emissions using multi-objective particle swarm optimization (MOPSO) technique. This technique evolves a multi-objective version of PSO by proposing redefinition of global best and local best individuals in multi-objective optimization domain. The optimal power flow (OPF) method using MOPSO is suggested to solve multi-objective functions including fuel cost and
emissions simultaneously. To show its efficiency and effectiveness, the results of the proposed method is comprehensively realized by a comparison with the ATC which is not including
emissions for the IEEE 30-bus system, and is found to be quite promising.
Application of Algorithm for Improving FI Error in DAS
Lim, Il-Hyung ; Choi, Myeon-Song ; Yun, Jun-Seok ; An, Tae-Pung ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1025~1033
This paper proposes a method to improve and analysis error cause of FI(Fault Indicator) information to be used for detecting fault section in distribution automation system. FI error cause is made by consideration fault current magnitude and time. So, a new method to prevent FI error is proposed to include fault current magnitude, time and direction. Therefore, it's considered network environments that grounded and ungrounded network in distribution automation system. The proposed method is proved by Matlap Simulink. By the result in this research, it's possible to quickly restoration, supplying stability and reliability power to customer.
Calculation of the Area of Severity for Voltage Sag Assessment
Park, Chang-Hyun ; Hong, Jun-Hee ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1034~1040
This paper presents a calculation method of the area of severity for the stochastic assessment of voltage sags. In general, the annual expected numbers of voltage sags at an individual load point can be estimated stochastically. However, in order to assess the system voltage sag performance considering many sensitive load points together, it is necessary to determine and analysis the area of severity for the load points. The area of severity to voltage sags is the network region where the fault occurrences will simultaneously lead to voltage sags at different load points. In this paper, the concept of the voltage sag assessment and the calculation method of the area of severity are addressed. The analysis of the area of severity is performed on the IEEE 30-bus test system by using the proposed method. The method is useful for the stochastic assesment of voltage sags and the establishment of systematic plans for voltage sag mitigation.
The 24 Hourly Load Forecasting of the Election Day Using the Load Variation Rate
Song, Kyung-Bin ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1041~1045
Short-term electric load forecasting of power systems is essential for the power system stability and the efficient power system operation. An accurate load forecasting scheme improves the power system security and saves some economic losses in power system operations. Due to scarcity of the historical same type of holiday load data, most big electric load forecasting errors occur on load forecasting for the holidays. The fuzzy linear regression model has showed good accuracy for the load forecasting of the holidays. However, it is not good enough to forecast the load of the election day. The concept of the load variation rate for the load forecasting of the election day is introduced. The proposed algorithm shows its good accuracy in that the average percentage error for the short-term 24 hourly loads forecasting of the election days is 2.27%. The accuracy of the proposed 24 hourly loads forecasting of the election days is compared with the fuzzy linear regression method. The proposed method gives much better forecasting accuracy with overall average error of 2.27%, which improved about average error of 2% as compared to the fuzzy linear regression method.
An Optimal Decision Model for Capacity and Inclining Angle of Residential Photovoltaic Systems
Jeon, Jeong-Pyo ; Kim, Kwang-Ho ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1046~1052
In residential house, photovoltaic (PV) system among various alternatives in renewable energy system is the most efficient and feasible solution for reducing energy consumption and electricity cost. However, relatively high initial cost make people reluctant to install PV system in their houses. Therefore, in the initial state for PV system installation in the house, it is very important to decide proper capacity of the PV system considering the expected energy usage and solar energy supplying condition with the house. This paper proposes a novel optimization model for deciding appropriate capacity of the PV system for residential house. The objective function of the model is to minimize the annual cost including electricity bill, operation and maintenance cost, and annual fixed cost calculated from the initial installation cost based on capital recovery factor (CRF). The model also shows the optimal inclining angle of PV panels of the system. In this paper, we estimate the PV output using PVWATTS (PV simulator of Office of Energy Efficiency and Renewable Energy) and find optimal solutions by Sequential Quadratic Programming (SQP) method using MATLAB software. The proposed approach is finally applied to a residential model house in Gangneung, Gangwon-Do and verified its feasibility for adopting to PV system design for residential houses.
Distance Relaying Algorithm for Intertie Protection of a Wind Farm Considering the Fault Ride-through Requirement
Kang, Yong-Cheol ; Kang, Hae-Gweon ; Zheng, Tai-Ying ; Kim, Yeon-Hee ; Lee, Young-Gui ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1053~1058
A large modern wind farm should satisfy the requirements for a grid and accomplish the optimization of the wind farm system. The wind farm intertie protection system should consider a Fault Ride-Through (FRT) requirement for more reliable protection. The wind farm should keep connected to the grid in the case of a grid fault whilst it should be isolated for an intertie fault. This paper proposes a distance relaying algorithm suitable for wind farm intertie protection considering the FRT requirement. The proposed algorithm estimates the impedance based on a differential equation method because the frequency of the voltage and current deviates the nominal frequency. The algorithm extends the reach of Zone 1 up to 100 % of the length of the intertie to implement the FRT requirement. To discriminate an intertie fault from a grid fault, the algorithm uses a voltage blocking scheme because the magnitude of the voltage at the relaying point for an intertie fault becomes less than that for a grid fault. The performance of the algorithm is verified using a PSCAD/EMTDC simulator under various fault conditions. The algorithm can discriminate successfully the intertie fault from grid fault and thus helps to implement the FRT requirement of a wind farm.
A Ferromagnetic Shimming Method for NMR Magnet Using Linear Programming
Lee, Sang-Jin ; Hahn, Seung-Yong ; Sim, Ki-Deok ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1059~1063
Shimming is an important technique in development of nuclear magnetic resonance (NMR) magnets where image resolution is highly dependent on magnetic field homogeneity. Classically, shimming may be categorized into two types: 1) active shimming that incorporates with extra coils and precise tuning of their currents; and 2)passive shimming that incorporates with pieces of steel placed in a bore of a main magnet and their uniform magnetization under homogeneous external fields. Additional magnetic fields, produced by the coils and/or the steel sheets, compensate original magnetic field from the main magnet in such a way that the total field becomes more homogeneous. In this paper, we developed a passive shimming method based on linear programming optimization. Linear programming is well known to be highly efficient to find a global minimum in various linear problems. We firstly confirmed the linearity of magnetization of ferromagnetic pieces under a presence of external magnetic fields. Then, we adopted the linear programming to find optimized allocation of the steel pieces in the inner bore of a main magnet to improve field homogeneity.
Inductor Characteristics of the Active Clamp Forward Converter for Adapter
Jang, Duk-Kyu ; Woo, Seung-Hun ; Kim, Chang-Sun ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1064~1069
Active clamp forward converter provides zero voltage switching, low voltage stress and wide input voltage range. The design technique leads to getting a higher efficiency under high switching frequency and optimal operating range. It is designed for notebook computer adapter with free input voltage and 19.5V/120W output ratings. The efficiency is measured to more than 90%. One of the most important circuit parts is the filter inductor besides the transformer in active clamp forward converter. In this paper, the process of inductor design is listed optimally.
A Study on the Capacity of the Off-line Station for PRT System
Lee, Jun-Ho ; Jeong, Rac-Gyo ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1070~1074
In this study we deal with a simple computer simulation algorithm to decide the PRT station capacity. PRT system is different from the conventional rail traffic system in such point that the station is off-line so as to guarantee a very short headway. This characteristic has correlation with the accurate prediction of the line capacity and with the scale of the off-line station. In this paper physical factors and vehicles per hour that are necessary to decide the off-line station scale and the off-line station capacity, respectively, are shown through a simple compter simulations.
Comparison Study of Maximum Power Point Tracking Control with Changing of Radiation
Choi, Jung-Sik ; Ko, Jae-Sub ; Chung, Dong-Hwa ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1075~1082
This paper analyzes a operating characteristic for maximum power point tracking (MPPT) of photovoltaic generation system. MPPT methods are used to maximize PV array output power by tracking maximum power point(MPP) continuously. To increase the output efficiency of PV system, it is important to have more efficient MPPT. MPPT algorithm is widely used the control method such as the perturbation and observation(PO) method, incremental conductance(IC) method and constant voltage(CV) method. In case of the radiation is changed, this paper proposes a response characteristic with MPPT control algorithms. Also, it proposes the direct for a novel MPPT control algorithm development through the analyzed data, hereby proves the effectiveness of this paper.
Electrical Properties with Annealing Temperature of SBN Thin Film
Kim, Jin-Sa ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1083~1086
thin films were deposited on Si substrate using RF magnetron sputtering method. And the SBN thin films were annealed at 650~800
]. The surface rougness showed about 0.42[nm] in annealed thin film at
]. The dielectric constant(150) of SBN thin film was obtained by annealing temperature above
]. The voltage dependence of dielectric loss showed a value within 0.02 in voltage ranges of -10~＋10[V]. The dielectric constant characteristics showed a stable value with the increase of frequency. Also, the SBN thin films annealed at
] showed a fatigue-free characteristics up to
Evaluation about Dielectric Property of Heat Transfer Fluids for Fuel Cell Vehicle using Cylindrical Multi-Terminal Capacitive-Conductive Sensor
Kim, Jae-Hoon ; Kim, Ju-Han ; Kim, Yoon-Hyung ; Choi, Kang-Wal ; Han, Sang-Ok ; Yong, Gee-Joong ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1087~1094
We have developed a cylindrical multi-terminal capacitive-conductive sensor that could be attached to the internal surface of cooling system pipe to evaluate capacitance and conductivity of heat transfer fluid. It was used as measuring system to diagnose insulating condition, by which was kept a insulating resistance of inner stack and at the same time was cooled electrochemical heat of reaction of FCEV(fuel cell electric vehicle) stack that used a compressed hydrogen gas reacting with oxygen in accordance with variation on thermal degradation of nonconductive heat transfer fluid. Also to assess diagnosis characteristics of heat transfer fluid, i.e. coolant, we have performed accelerated aging test using developed sensor attached to cooling system. Consequently, it was measured dielectric and electric resistance of coolant to estimate and analyse for dielectric properties by degradation condition.
An Equalizing Algorithm for Cell-to-Cell Interference Reduction in MLC NAND Flash Memory
Kim, Doo-Hwan ; Lee, Sang-Jin ; Nam, Ki-Hun ; Kim, Shi-Ho ; Cho, Kyoung-Rok ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1095~1102
This paper presents an equalizer reducing CCI(cell-to-cell interference) in MLC NAND flash memory. High growth of the flash memory market has been driven by two combined technological efforts that are an aggressive scaling technique which doubles the memory density every year and the introduction of MLC(multi level cell) technology. Therefore, the CCI is a critical factor which affects occurring data errors in cells. We introduced an equation of CCI model and designed an equalizer reducing CCI based on the proposed equation. In the model, we have been considered the floating gate capacitance coupling effect, the direct field effect, and programming methods of the MLC NAND flash memory. Also we design and verify the proposed equalizer using Matlab. As the simulation result, the error correction ratio of the equalizer shows about 20% under 20nm NAND process where the memory channel model has serious CCI.
Analysis for the Grounding Impedance of Vertical Grounding Electrodes using the Distributed Parameter Circuit Model
Lee, Bok-Hee ; Kim, Jong-Ho ; Choi, Jong-Hyuk ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1103~1108
A grounding electrode has the transient grounding impedance characteristics against lightning surges. So the performance of grounding electrodes should be evaluated as a grounding impedance as well as the ground resistance. The frequency-dependent grounding impedance is varied with the shape and size of grounding electrode and is divided into both inductive and capacitive behaviors. This paper presents a theoretical analysis for the grounding impedance determined by the size of grounding electrode using the distributed parameter circuit model. EMTP and Matlab programs were used in calculating the frequency-dependent grounding impedances of vertical grounding electrodes. It was found that the frequency-dependent grounding characteristics of vertical grounding electrodes are characterized by the distributed parameters which are changed in the dimension of grounding electrodes.
Influence of Flux Density of Electric Leakage Area by Inundation
Choi, Woon-Shik ; Kim, Tag-Yong ; Kim, Jin-Sa ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1109~1113
Recently, important for the safety has been increasing together economic developments. The leakage only is measured by the voltage difference. This method is a way to contact the electric leakage area. It can cause electric shock at users. We propose a non-contact method to detect a short circuit in this paper. We investigate magnetic field at electric leakage area to present non-contact method. Simulated environment created a short circuit in the flooded areas. Voltage is supplied 50, 150 and 200[V]. Magnetic field was measured at 0, 5 and 10[cm]. Magnetic flux was reduced about
depending on the distance changes in the steady region. But we confirmed that magnetic flux is measured the same value depending on the distance changes in the electric leakage area.
Analysis of Electromagnetic Wave Propagation from 2 Dimensional Random Rough Surfaces
Yoon, Kwang-Yeol ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1114~1119
This paper is concerned with an numerical analysis of electromagnetic wave propagation from randomly rough surfaces as a desert, sea surface and so on. We propose discrete ray tracing method (DRTM) for analysis of characteristics of wave propagation along one dimensional (1D) and two dimensional (2D) random rough surfaces. The point of the present method is to discretize not only rough surface but also ray tracing. This technique helps saving computer memories and does simplifying ray searching algorithm resulting in saving computation time. Numerical calculations are carried out for 1D and 2D random rough surfaces and electric field distributions are shown to check the effectiveness of the proposed DRTM.
A Speech Enhancement Algorithm based on Human Psychoacoustic Property
Jeon, Yu-Yong ; Lee, Sang-Min ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1120~1125
In the speech system, for example hearing aid as well as speech communication, speech quality is degraded by environmental noise. In this study, to enhance the speech quality which is degraded by environmental speech, we proposed an algorithm to reduce the noise and reinforce the speech. The minima controlled recursive averaging (MCRA) algorithm is used to estimate the noise spectrum and spectral weighting factor is used to reduce the noise. And partial masking effect which is one of the human hearing properties is introduced to reinforce the speech. Then we compared the waveform, spectrogram, Perceptual Evaluation of Speech Quality (PESQ) and segmental Signal to Noise Ratio (segSNR) between original speech, noisy speech, noise reduced speech and enhanced speech by proposed method. As a result, enhanced speech by proposed method is reinforced in high frequency which is degraded by noise, and PESQ, segSNR is enhanced. It means that the speech quality is enhanced.
Vocal Tract Modeling with Unfixed Sectionlength Acoustic Tubes(USLAT)
Kim, Dong-Jun ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1126~1130
Speech production can be viewed as a filtering operation in which a sound source excites a vocal tract filter. The vocal tract is modeled as a chain of cylinders of varying cross-sectional area in linear prediction acoustic tube modeling. In this modeling the most common implementation assumes equal length of tube sections. Therefore, to model complex vocal tract shapes, a large number of tube sections are needed. This paper proposes a new vocal tract model with unfixed sectionlengths, which uses the reduced lattice filter for modeling the vocal tract. This model transforms the lattice filter to reduced structure and the Burg algorithm to modified version. When the conventional and the proposed models are implemented with the same order of linear prediction analysis, the proposed model can produce more accurate results than the conventional one. To implement a system within similar accuracy level, it may be possible to reduce the stages of the lattice filter structure. The proposed model produces the more similar vocal tract shape than the conventional one.
A Study on Multi-Sensor System for Detection of Chronic Mild Stress
Lee, Ji-Hyeoung ; Kim, Kung-Ho ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1131~1135
The development of modern civilization result from the abundance of material. Yet modern people live with chronic mild stress. Excessive chronic mild stress leads to various diseases. From the risk of the disease in order to protect our bodies need to manage chronic mild stress. The purpose of this study is to inspection the effectiveness of detecting in chronic mild stress using the Multi-sensor system. The Multi-sensor system is designed that can be measure three kinds of vital signals of chronic mild stress for the detection. First Photoplethysmogram(PPG), second Electro Dermal Activity(EDA), third Skin Temperature(SKT). The ages and occupations exposed to chronic mild stress, people often use out of this system was applied to dairy products(Pen). In addition, vital signals that occur when the variety of noise was used to remove the accelerometer. Chronic mild stress by the analysis of measured vital signals from Multi-sensor system to the measurement information to a PC to a wireless transmission(Bluetooth). In this study, using Multi-sensor system writing conditions and a variety of situations in the movement to measure vital signals and measurement results verified the accuracy and reliability. Through this measure chronic mild stress in everyday life and managing to maintain will help more healthy lifestyle.
Individual Tooth Image Segmentation with Correcting of Specular Reflections
Lee, Seong-Taek ; Kim, Kyeong-Seop ; Yoon, Tae-Ho ; Lee, Jeong-Whan ; Kim, Kee-Deog ; Park, Won-Se ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1136~1142
In this study, an efficient removal algorithm for specular reflections in a tooth color image is proposed to minimize the artefact interrupting color image segmentation. The pixel values of RGB color channels are initially reversed to emphasize the features in reflective regions, and then those regions are automatically detected by utilizing perceptron artificial neural network model and those prominent intensities are corrected by applying a smoothing spatial filter. After correcting specular reflection regions, multiple seeds in the tooth candidates are selected to find the regional minima and MCWA(Marker-Controlled Watershed Algorithm) is applied to delineate the individual tooth region in a CCD tooth color image. Therefore, the accuracy in segmentation for separating tooth regions can be drastically improved with removing specular reflections due to the illumination effect.
Enhancement of ST-segment Features in ECG Signals by Warping Transformation
Shin, Seung-Won ; Kim, Kyeong-Seop ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1143~1149
In this study, we propose a novel method to detect and enhance the feature of ST-segment which offers the crucial information for the diagnosis of myocardial infarction and ischemia. With this aim, PQRST features of Electrocardiogram initially are detected and subsequently ST-segment are estimated. And Dynamic Time Warping(DTW) transformation is applied recursively to minimize the difference in time between ST-segments and calculate the minimum cumulative distance that decides the degree of similarity among ST-segments. As of the results, the inherent characteristic of ST-segment can be emphasized in terms of time parameter and thus the diagnostic features of a ST-segment can be revealed further.
Design of Bowing-Activity Monitoring and Automatic Detection System Using 3-Axis Accelerometer
Lee, Young-Jae ; Lee, Pil-Jae ; Cha, Ji-Young ; Sunoo, Sub ; Hwang, Jin-Sang ; Lee, Jeong-Whan ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1150~1158
In this paper, a new reliable portable activity monitoring device implemented with the buddhist-style bowing activity and walking step detection algorithm, is presented. In order to monitor the bowing and walking activities, miniaturized 3-axis accelerometer sensor with the sensitivity of 800 mV/g was used. After initial signal conditioning, vector magnitude of accelerometer signals was calculated. Syntactic peak detection method was used in order to feature points. All signal processing algorithms were implemented in ultra-low power microcontroller MSP430 with double precision floating point arithmetic. For evaluation, 19 young man(
yrs) and woman(
yrs) were involved. The accuracy of the proposed algorithms were 98.91 %(
) for walking step detection and 98.25 %(
) for buddhist-style bowing activity. Comparing to the commercialized pedometer accuracy, 87.1 %(
), the proposed walking step detection algorithms show more reliable accuracy.
Design of HCBKA-Based TSK Fuzzy Prediction System with Error Compensation
Bang, Young-Keun ; Lee, Chul-Heui ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1159~1166
To improve prediction quality of a nonlinear prediction system, the system's capability for uncertainty of nonlinear data should be satisfactory. This paper presents a TSK fuzzy prediction system that can consider and deal with the uncertainty of nonlinear data sufficiently. In the design procedures of the proposed system, HCBKA(Hierarchical Correlationship-Based K-means clustering Algorithm) was used to generate the accurate fuzzy rule base that can control output according to input efficiently, and the first-order difference method was applied to reflect various characteristics of the nonlinear data. Also, multiple prediction systems were designed to analyze the prediction tendencies of each difference data generated by the difference method. In addition, to enhance the prediction quality of the proposed system, an error compensation method was proposed and it compensated the prediction error of the systems suitably. Finally, the prediction performance of the proposed system was verified by simulating two typical time series examples.
A New Robust Discrete Integral Variable Structure Controller with Disturbance Observer for Uncertain Discrete Systems
Lee, Jung-Hoon ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1167~1172
In this paper, a new discrete integral variable structure controller based on the a new sliding surface and discrete version of the disturbance observer is suggested for the control of uncertain linear systems. The reaching phase is completely removed by introducing a new proposed integral sliding surface. The discrete version of disturbance observer is derived for effective compensation of uncertainties and disturbance. A corresponding control with disturbance compensation is selected to guarantee the quasi sliding mode on the predetermined integral sliding surface for guaranteeing the designed output in the integral sliding surface from any initial condition for all the parameter variations and disturbances. Using Lyapunov function, the closed loop stability and the existence condition of the quasi sliding mode is proved. Finally, an illustrative example is presented to show the effectiveness of the algorithm.
A New Robust Integral Variable Structure Controller for Uncertain More Affine Nonlinear Systems with Mismatched Uncertainties
Lee, Jung-Hoon ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1173~1178
In this note, a systematic design of a new robust nonlinear integral variable structure controller based on state dependent nonlinear form is presented for the control of uncertain more affine nonlinear systems with mismatched uncertainties and matched disturbance. After an affine uncertain nonlinear system is represented in the form of state dependent nonlinear system, a systematic design of a new robust nonlinear integral variable structure controller is presented. To be linear in the closed loop resultant dynamics and remove the reaching phase problems, the linear integral sliding surface is suggested. A corresponding control input is proposed to satisfy the closed loop exponential stability and the existence condition of the sliding mode on the linear integral sliding surface, which will be investigated in Theorem 1. Through a design example and simulation studies, the usefulness of the proposed controller is verified.
Design of a Robust Controller for Position Control of a Small One-Link Robot Arm with Input Time-Delay
Jeong, Goo-Jong ; Kim, In-Hyuk ; Son, Young-Ik ;
The Transactions of The Korean Institute of Electrical Engineers, volume 59, issue 6, 2010, Pages 1179~1185
This paper deals with a robust controller design problem for a small one-link robot arm system subject to input time delay and load variations. The uncertain parameters of the system are considered as a disturbance input. A disturbance observer(DOB) has been designed to alleviate disturbance effects and to compensate performance degradation owing to the time-delay. This paper employs a new DOB structure for non-minimum phase systems together with the Smith predictor. We propose a new controller for reducing the both effects of disturbance and time-delay. In order to test the performance of proposed controller, four different other control laws are compared with the proposed one by computer simulations. The simulation results show the effectiveness of the proposed control method.