단상전원하에서의 정지형상변환기에 의한 3상유도전동기의 평형운전

趙哲濟 釜山工業大學 1987 論文集 Vol.29 No.-

Utilization of three-phase induction motor under single-phase power supply causes trouble of unbalanced operation in non-fractional horsepower rating. In this paper, a simple phase converter consisting of a saturable reactor and a capacitor in parallel with an iron-core coil is presented. The converter impedances necessary for a balanced operation of a monocyclic three-phase induction motor is determined from the two sides of a parallelogram whose diagonal is the positive-sequence admittance vector of the motor. It is possible to maintain a satisfactory blalanced operation over a certain range of speed and is considered sufficient to overcome difficulties arising in practical applications.

준슬라이딩 모드를 이용한 강인한 로보트 매니퓰레이터 제어기 설계

趙俊翼,咸喆柱 군산대학교 1991 群山水産專門大學 硏究報告 Vol.25 No.1

In this paper, a robust control method which can overcome the disturbances and parameters uncertainties of a robot manipulator is proposed. We design the controller of that Robot manipulator by adaptation DVSS control theory with quasi-sliding mode and equivalent control input on the basis of linearized dynamic equation of Robot manipulator with two links which are derived by using Lagrange-Euler formulation. It is insensitive to vary of system parameters and external disturbances ; moverover, the chattering effect can be eliminated in the suggested DVSS controller. From the IBM-PC/AT simulation results, it's shown that by using the proposed controller we have fast response with a very small overshoot in the existing nonlinear interaction and parameter changes, and steady-state error is under 0.1%. We confirm the validity and the stability of suggested dynamic Robot-Arm-Manipulator model with DVSS controller.

유연한 관절을 갖는 단일 링크 로보트에 대한 비선형 제어기 설계

趙俊翼,咸喆柱 군산대학교 1993 群山水産專門大學 硏究報告 Vol.28 No.1

In this paper we present the robust controller for the nonlinear system using feedback linearization applying Min-Max control based on the Lyapunov second method. The robustness against parameter uncertainties for robot manipulators with flexible joint is considered. Simulation results are presented and show the advantage of the proposed nonlinear control method.

교류서보전동기의 용도별 선정기준에 관한 연구

조철제 釜山工業大學校 1992 論文集 Vol.34 No.-

As the ac servo systems are of recent development and their advantages have not been published in detail, it is very difficult for the user and application engineer to choose and appropriate type of serbo drive from the ac servo group for a particular application. In the view of power density and acceleration characteristics of the servo drive, ac servo are being recognized superior to those of the existing dc counterpart. Thus, this study is intended to develop a set of selection criteria to distinguisg the various servo drives of the ac servo group. The considered factors are cost, power density, acceleration charateristics, torque per unit ampere, peak torque capability, rotor postion detector, etc.

回轉型相變換機에서의 中性點移動 方式에 의한 電流平衡率改善

趙哲濟 釜山工業大學校 1986 論文集 Vol.28 No.1

The use of phase converters to supply three-phase power from existing single-phase lines where extension of three phase service is impractical hasbecome a significant factor in rural electrification. Applications have expanded from purwly agricultural to many light industrial and suburban ones. This paper presents the analysis of the rotary converter having several taps for winding offset along with adjustable capacitor. The running performance is analyzed by using modified symmetrical component theory. It has been shown that it is possible to keep down the umbalance ratio of the load motor currents from typical 15 percent current unbalance by conventional rotary converter to 5 percent or below at full load

三脚鐵心構造를 가진 周波數 3倍器의 開發에 關한 實驗的硏究

趙哲濟 釜山工業大學校 1986 論文集 Vol.28 No.1

A magnetic frequency tripler is a nonlinear device that is used to produc third-harmonic frequency output from a three-phase fundamental fre quency source. It gained wide industrial applications recently and its rating for induction heating and melting increased from 50 KW to 10MW range. This paper deals with the tripler employing three 3-legged transformers connected in delta. Because a triple frequency current circulates in delta connection and does not flow into the input line, the input current has very little distortion and the value of it changes very little with the fluctuations of the input volage and the load. Simultaneously, the consumption of iron and copper is about same as of the traditional star-connected circuit. The analysis in this paper is based on the model of an idean lossless tripler and the relations between the saturation characteristics and circuit constants are examined through the experiment.

이산 가변구조 서보 디지탈 제어기 구현과 응용

趙俊翼,咸喆株 군산대학교 1991 群山水産專門大學 硏究報告 Vol.25 No.2

This paper presents the design, implementation and application of a microcomputer- based interactive digital controller development system. A microcomputer- based incremental servo system with a discrete variable structure for motor speed is presented with respect to the dynamic response and accuracy of controlled speed. Complicated digital control algorithm can be synthesized by using fundamental software building blocks. It is concluded that a robust DVSS (Discrete Variable Structure System) digital controller for motor speed control can be practically designed and implemented with currently available technique and hardware. The experimental results show that usage of DVSC (Discrete Variable Structure Controller) can greatly improve the transient performance of the system.

MK2 로봇에 대한 가변구조 위치제어와 MSDS 분석에 관한 연구

함철주,조준익 群山大學校 情報通信技術硏究所 1998 情報通信技術硏究論文集 Vol.2 No.-

Analyzing the kinematic or dynamic equations of motion for coordination and control of a robotic system, we adopt a graphical simulation to animate the motion results. A new control algorithm is developed for manipulators using the theory of variable structure systems. To illustrate the design procedures, a two-joint manipulator is considered. The hybrid simulation method has demonstrated that the variable structure approach is applicable to manipulator controller design.

스위치드 릴럭턴스 전동기의 전류 파형

안영주,배규환,조철제 釜山工業大學校 1995 論文集 Vol.37 No.-

In this paper, a control method to flow the flat top current into the expected phase of variable reluctance motors(VRMs) is described. Current waveforms of SRM are directly related to the VRM performances. These are greatly influenced by topologies of driving converter. In order to flow the flat top current in the expected phase, conditions of excitation voltage such as the magnitude and on/off timing should be found out. To verify this control method, SRM drive system of a 6/4 pole VRM, controlled rectifier and classic inverter is constructed and tested. The experimental results show that this control method performs well the flat top current.

Isolation and Characterization of Epidermal Mucus from hirudo nipponia

Joe, Cheol O,Kang, Ke Won,Lee, Ju Yun 생화학분자생물학회 1981 BMB Reports Vol.29 No.3

The epidermal organ of the leech contains a complex glycoprotein molecule of mucus. The mucus excreted from annelids plays significant role in protection against desiccation and parasites. Mucus from the Korean native leech, H. nipponia, was investigated for biochemical characteristics for possible development of biomaterials of cosmetic and pharmaceutical agents. The leech skin mucus was heavily glycosylated mucin-like protein with a high molecular weight comprised 80% carbohydrate and 20% protein. Threonine, serine, and glycine were the major components of the isolated protein and these accounted for 50% of total amino acids. The carbohydrate portion contained glucosamine, galactosamine, galactose, glucose, mannose and sialic acid in oligosaccharide form linked with threonine and serine residues of the glycoprotein.