• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 F
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• pp.2107-2109
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• 1997

Speed sensors are required for the vector control of induction motors. These sensors reduce the sturdiness of the system and make it expensive. Therefore, a drive system without speed sensors is required. Also, the rotor inertia constant, the damping constant and the disturbed load torque of the IM are estimated by the RLS estimator and a torque observer. Then the observed disturbance torque is fed forward to increase the robustness of the IM speed drive.

• Journal of Electrical Engineering and Technology
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• 제10권5호
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• pp.2052-2056
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• 2015

This Paper analyzes the characteristics of the WRSM in high-speed operation range. To verify the control characteritics of various WRSM models, the relative position of the central point of current limit circle and voltage limit ellipse is defined as M value and 3 models according to M_max value are designed through inductance change. Through the designed models, the current control method of 3-variables control for maximum power especially in high-speed operation range is presented.

• 한국철도학회논문집
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• 제17권5호
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• pp.349-354
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• 2014

신호시스템은 외국의 경우에는 이미 ETCS LEVEL 2 시스템이 적용되었는데 이는 ETCS LEVEL 1에서 무선 통신을 이용하여 열차를 연속 제어 하는 기능이 추가된 것이다. 더욱이 ETCS LEVEL 2 시스템을 적용한 영업 노선은 점점 확산되고 있는 추세이다. 이에 따라, 국내에서도 향후 LEVEL 2 적용을 위해 관련 핵심기술 개발을 진행하고 있다. ETCS LEVEL 2 시스템의 핵심기술은 열차 방호를 위한 ATP 기능을 열차 운행 중 LEVEL 1 과 같은 비연속적 제어에서 발전하여 연속적으로 실행함으로써 승객의 안전성을 높인 상향 시스템 모델이다. 본 논문에서는 ETCS LEVEL 2 시스템을 위한 차상 속도 프로파일 설계 방안에 대한 연구를 기술하고 ETCS 적용을 위한 예상 결과를 고찰해본다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제5권2호
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• pp.89-101
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• 2005

Research on highly abstracted system modeling and simulation has received a great deal of attention as of the concept of platform based design is becoming ubiquitous. From a practical design point of view, such modeling and simulation must consider the following: (i) fast simulation speed and cycle accuracy, (ii) early availability for early stage software development, (iii) inter-operability with external tools for software development, and (iv) reusability of the models. Unfortunately, however, all of the previous works only partially addresses the requirements, due to the inherent conflicts among the requirements. The objective of this study is to develop a new system design methodology to effectively address the requirements mentioned above. We propose a new transaction-level system modeling methodology, called ViP (Virtual Platform). We propose a two-step approach in the ViP method. In phase 1, we create a ViP for early stage software development (before RTL freeze). The ViP created in this step provides high speed simulation, lower cycle accuracy with only minor modeling effort.(satisfying (ii)). In phase 2, we refine the ViP to increase the cycle accuracy for system performance analysis and software optimization (satisfying (i)). We also propose a systematic ViP modeling flow and unified interface scheme based on utilities developed for maximizing reusability and productivity (satisfying (ii) and (iv)) and finally, we demonstrate VChannel, a generic scheme to provide a connection between the ViP and the host-resident application software (satisfying (iii)). ViP had been applied to several System-on-a-chip (SoC) designs including mobile applications, enabling engineers to improve performance while reducing the software development time by 30% compared to traditional methods.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.1798-1799
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• 2011

In this paper, A new cost-effective and accurate input noise rejection method for High Speed Counter module of PLC (Programmable Logic Controller) is proposed. By using combination of simple additional logic circuit and the Timer Pulse function of general purpose MPU, Cost-effectiveness and improvement of accuracy of filtering function can be achieved. This proposed method is verified by simulation. This proposed method is much useful for simple industrial controller based on simple microprocessor because of simplicity, accuracy and low cost.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.1376-1381
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• 2010

In this study, we dealt with an analysis and development of measurement systems for tunnel and slope structures under a high velocity. Deterioration of tunnel and slope structures becomes a critical issue in regard to both safety and economic concerns. Deterioration itself is inevitable, but condition assessment technology and nondestructive evaluation techniques could provide solutions to ensure public safety by means of detecting damage before serious and expensive degradation consequences occur. We reviewed the existing monitoring and maintenance systems of slopes and tunnels and more advanced directions, especially for highways under high-speed vehicles.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 26-27 Oct. 1990
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• pp.913-916
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• 1990

In this paper, attempts have been made to control AC synchronous servo motor used as actuators of joints of the FARA robot with high dynamic performance and precise positioning. The AC synchronous servo motors used in FARA robots have resolves as position sensors. Resolver to digital converters are used in order to obtain the information of rotor speed and position from resolver outputs. The proposed joint position control system consists of four speed controller and one position controller. Analog methods are used in the position controller, while digital methods are used in the position controller. For precise position control, PID control algorithm and interpolation functions are executed in two 16 bit microprocessors with sampling rate 2ms. Experimental results show that the proposed joint position control system can be effectively applied to industrial robots in order to obtain high dynamic performance and precise positioning. The proposed joint position control system is being used in the control of FARA robots of Samsung Electronics.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1988년도 한국자동제어학술회의논문집(국내학술편); 한국전력공사연수원, 서울; 21-22 Oct. 1988
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• pp.414-417
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• 1988

Recently PLC pursues faster scanning time, circuit confidence, reliability improvement, and smaller size. To obtain above all merit, custom IC(Gate Array) is developed. Custom IC includes 5 main blocks and 2 auxiliary blocks. The 5 main blocks process faster sequential instruction execution by only logic gate using hexa instruction code system. And the 2 auxiliary blocks generate baud rate clock (153.6 KHz, 76.8KHz) to communicate between PLC and computer or programmers.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 추계학술대회 논문집 학회본부
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• pp.24-26
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• 1995

The Development of A.C. Induction Motor for Railway Rolling Stock. The traction motor is designed as 4-pole induction motor with self ventilation. The winding insulation is throughout of materials of class C. The rotor is designed as a squrrel rotor with copper bar and casting. The rotor speed is detected by means of a pulse generator. The newer tection motor have no casting(frame). Punched-in holes make up the air duct and transfer the heat losses in complete. Maximim motor rpm is higher due to rotor construction. New is the entry of water-cooled traction motors in urban, However the water cooling design in - unfortunately - not applicable in traction motor.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 A
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• pp.98-100
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• 1995

This paper deals with development of high torque and high accurate stepping motor and control system which is adopted heavy equipment engine speed control. In the process of development, only pure domestic technics is involved, all the parts are supplied in domestic industries, and successfully accomplished to mass production. In order to confirm product liability, circumferential test,such as vibration test impact test,thermal test,and field test are thoroughly fulfilled.