• 대한전기학회논문지:전력기술부문A
• /
• 제52권7호
• /
• pp.381-386
• /
• 2003

To provide a specified power quality under electric market system is becoming an important issue for customers and utility company. However, there is no realistic infra-structure to design a power system for the specified power quality. Present electric market is operating under the economic point of view. The low power price could be attractive, but the effect of low price could result the lower power quality for the long time and threat power system security. This paper presents a model which conceptualize the dynamic power quality control mechanism to minimize total cost of a society which is affected electric power quality. This model aims to produce a basic infra-structure to balance cost and quality under the electric market system.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2003년도 하계학술대회 논문집 B
• /
• pp.1208-1210
• /
• 2003

Most of all, DTC drive is very simple in its implementation because it needs only two hysteresis comparator and switching vector table for both flux and torque control. The amplitude of hysteresis band greatly influences on the drive performance such as flux and torque ripple and inverter switching frequency. In this paper the influence of the amplitudes of flux and torque hysteresis bands and sampling time of control program on the torque and flux ripples are investigated. Simulation results confirm the superiority of the DTC under the proposed method over the conventional DTC.

• 한국환경보건학회지
• /
• 제20권3호
• /
• pp.61-77
• /
• 1994

Sprague Dawley rats were exposed to electric fields (6,000 V, 10 kV/m, 30 min/day, 6 days per week) and injected strontium 90 (681 kbq/rat, one time) through abdominal cavity (strontium 90 and electric field complexed exposure group). In parallel, series with the electric field exposure only, strontium 90 injection only and control groups were run. Every group was consisted of 110 rats (55 male and 55 female). This animal experiment was performed from May to December in 1993. This results were conducted to investigate the effect of electric field for 11 weeks. The results are summarized as follows: 1. Ornithine decarboxylase (ODC) activity in rat's bone marrow cells: The ODC values was significantly increased in Sr$^{90}$ injection group and Sr$^{90}$ and electric field complexed exposure group as compared with that of control group (p<0.05). The ODC value was significantly decreased in electric field and Sr$^{90}$ complexed exposure group in comparison with Sr$^{90}$ injection group (p<0.05). The ODC values of electric field only exposure group was not different to that of control group (p>0.05). 2. The amount of Sr$^{90}$ accumulation in the femur, kidney and spleen:The accumulation amount of Sr$^{90}$ in the femur of Sr$^{90}$ injection group represented higher value than that of electric field and Sr$^{90}$ complexed exposure group (p<0.05). In the kidney and spleen, the difference between electric field and Sr$^{90}$ complexed exposure group and Sr$^{90}$ injection group wasn't observed. 3. The counts of white cells in blood of Sr9?injection group was decreased as compared with the value from control group and electric field and Sr$^{90}$ complexed exposure group (p<0.05). The rat's body weight, red blood cell counts and the weight data of liver, kidney and spleen did not show differences among four groups.

• 제어로봇시스템학회논문지
• /
• 제5권6호
• /
• pp.683-690
• /
• 1999

This paper deals with a fault-tolerant control method for robust control of RPV(Remotely Piloted Vehicle). To design the flight control system, the 6-DOF simulation program has been developed based on the dynamic model of RPV. A robust fault detection and diagnosis method proposed by Kwon et al. [8]-[10] is adopted to detect the actuator fault of RPV and to make the controller reconfiguration. The Hoo control method is applied to the flight control system. An integrated simulation for performance evaluation of the fault-tolerat\nt control system designed is performed via 6 DOF simulation and shows that the control system works even under the actuator fault.

• 한국철도학회논문집
• /
• 제13권2호
• /
• pp.173-178
• /
• 2010

전기철도는 전력공급시스템과 전기차로 구성되어 있다. 전기철도의 전기차는 대규모의 견인력을 얻을 수 있어 대량수송과 고속운전에 적합하다. 전기차는 모터블록과 견인전동기에 의해서 구동되며, 지령속도에 따라 모터블록에서 견인전동기에 전력을 공급하여 속도가 제어된다. 전기차의 속도제어는 모터블록과 견인전동기의 최소 에너지로 속도를 제어하는 것이 목표이다. 최근의 견인전동기는 직류 및 동기전동기에서 유도전동기를 사용하고 있다. 대부분의 유도전동기는 벡터제어기법을 사용하여 유도전동기의 속도를 제어한다. 본 논문에서는 유도전동기의 벡터제어기법을 이용하여 유도전동기의 속도를 제어하였다. Simulink를 이용하여 제어시스템을 모델링하고, PI 제어기와 Hysteresis 제어기를 이용하여 펄스를 제어하여 전동기의 속도를 제어하였다. 실시간 제어를 위해 IGBT 인버터를 사용하였고, 유도전동기 구동실험에 의해 시스템 성능을 입증하였다.

• 한국지능시스템학회논문지
• /
• 제23권4호
• /
• pp.281-285
• /
• 2013

본 논문에서는 전기 자동차의 정속 주행을 위하여 구간제어기법을 이용한 속도제어기의 설계방안을 제안한다. 전기자동차의 정속주행은 주요한 성능요소중의 하나이다. 정속주행을 위해서는 이상적으로 선형적 특성을 가진 구동 모터가 필요하다. 하지만 실용화된 모터는 비선형적인 구간이 존재하며 이를 보상하기 위해 폐루프 제어를 통해 성능을 향상시킬 수 있다. 본 논문에서는 비선형적인 특성이 매우 큰 구동모터는 폐루프 제어만으로 적합한 성능을 얻기 어렵기 때문에 구간제어기법을 적용하여 성능을 향상시켰다. 제안한 방법을 실험하기 위하여 비선형 특성이 큰 구동모터를 장착한 전기자동차를 구성하고 제안한 방법을 적용하여 실험하였다. 실험 결과 폐루프 제어보다 제안한 구간제어기법이 우수한 성능을 보임을 확인하였다.

• 전기학회논문지P
• /
• 제65권4호
• /
• pp.273-279
• /
• 2016

In this paper, a high-performance control of the induction motor for electric car was implemented to escape dependence of the rare earth magnet. Proposed high-efficiency control algorithm is a Direct Rotor Field-Oriented Control method that is insensitive to the fluctuation of motor parameters. In the DRFOC method, we need to compensate fluctuation of stator transient inductance and magnetizing inductance caused by the magnetic saturation of induction motor in high-speed area. This paper proposes Back-EMF Observer based on stator current estimator of Luenberger style. Motor control system applied the Voltage Feedback Flux Weakening Control method for high-speed operation. The proposed algorithm was verified through tests by the power train of Extended Range Electric Vehicle consists of induction motor and differential gear.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2001년도 전력전자학술대회 논문집
• /
• pp.124-127
• /
• 2001

가상현실 기술을 이용한 컴퓨터 지원 교육훈련 시스템 (VR-CATS: Virtual Reality based Computer Assisted Training System) 개발에 대한 연구를 전력연구원에서는 계속 수행해 왔다. 본 논문에서는 New VR-CATS (울진 3호기 참조)중 가상현실에서의 공동 협동 훈련 시스템(Virtual Reality Collaboration Training System)의 설계에 관하여 서술한다. 공동작업은 발전소 MCR(Main Control Room)을 3D 데이터 모델링 후 가상현실화하고 MCR 내부를 Navigation 할 수 있도록 가상패널(Virtual Panel)을 개발 및 에에 대한 엔지니어링 데이터베이스환경을 작성하여 추후 정확하고 신속한 계기 정보를 얻을 수 있도록 하며 훈련생들이 시뮬레이터실로 가지 않고 MCR에서 발전소를 운전하는 것과 같은 효과를 강의실에서 얻을 수 있다. 또한 설계기준사고 중의 하나인 LOCA 사고 복구 훈련 시나리오를 통하여 실제와 동일한 복구 훈련을 하므로서 효율적이며 현장감있는 교육훈련 수행을 가능케 한다.

• 한국정밀공학회지
• /
• 제26권5호
• /
• pp.120-127
• /
• 2009

An electric furnace, inside which desired temperatures are kept constant by generating heat, is known to be a difficult system to control and model exactly because system parameters and response delay time vary as the temperature and position are changed. In this study the heating system of ceramic drying furnaces with time-varying parameters is mathematically modeled as a second order system and control parameters are estimated by using a RIV (Recursive Instrumental-Variable) method. A modified bang-bang control with magnitude tuning is proposed in the time optimal temperature control of ceramic drying electric furnaces and its performance is experimentally verified. It is proven that temperature tracking of adaptive time optimal control using a second order model is more stable than the GPCEW (Generalized Predictive Control with Exponential Weight) and rapidly settles down by pre-estimation of the system parameters.

• 전기학회논문지P
• /
• 제60권3호
• /
• pp.138-143
• /
• 2011

Electric locomotive is adapted to high speed driving and mass transportation due to obtaining high traction force. The electric locomotive is operated by motor blocks and traction motors. Train speed is controlled by suppling power from motor blocks to traction motors according to reference speed. Speed control of the electric locomotive is efficient by spending energy between motor blocks and traction motors. Currently, switched reluctance motors have been studied because the efficient is higher than induction motors. In this paper, model of the switched reluctance motor is presented and the PID controller is applied to the model for the speed control by using Simulink. Asymmetry converter is used for real-time control and system performance is demonstrated by simulating the speed of switched reluctance motor including PID controller.