• 풍력에너지저널
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• 제9권4호
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• pp.47-56
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• 2018

This paper introduces an active power dependent standard characteristic curve, Q(P) to compensate for voltage variations due to the output of distributed generation. This paper presents an efficient control method of grid-connected inverters by comparing and analyzing voltage variation magnitude and line loss according to the compensation method. Voltage variations are caused not only by active power, but also by the change of reactive power flowing in the line. In particular, the system is in a relatively remote place in a coastal area compared with existing power plants, so it is relatively weak and may not be suitable for voltage control. So, since it is very important to keep the voltage below the normal voltage limit within the specified inverter capacity and to minimize line loss due to the reactive power. we describe the active power dependent standard characteristic curve, Q(P) method and verify the magnitude of voltage variation by simulation. Finally, the characteristics of each control method and line loss are compared and analyzed.

• Journal of Electrical Engineering and Technology
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• 제10권5호
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• pp.2083-2088
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• 2015

The transient characteristics of the tri-axial High Temperature Superconducting (HTS) power cable are different from those of a conventional power cable depending on whether the cable is under a steady or transient state due to the quench. Verification using simulation tools is required to confirm both the characteristics of the cable and the effect of the cable when it is applied to a real utility. However, a component for the cable has not been provided in simulation tools; thus the RTDS-based model component of the tri-axial HTS power cable was developed, and a simulation was performed under the transient state. The considered properties of model component include resistance, reactance and temperature. Simulation results indicate the variation of HTS power cable condition. The results are used for the transient characteristic analysis and stability verification of the tri-axial HTS power cable. In the future, the RTDS-based model component of the cable will be used to implement the hardware-in-the-loop simulation with a protection device.

• 한국유체기계학회 논문집
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• 제9권6호
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• pp.22-28
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• 2006

Operation of a microturbine was simulated on the basis of component characteristic parameters obtained from performance test. Characteristic parameters, such as compressor and turbine efficiencies, recuperator effectiveness as well as turbine inlet temperature, were obtained for a wide operation range. Component characteristics including performance maps and characteristic curves were generated using measured data. Based on the component characteristics, a simulation program was constructed and operation of the microturbine was simulated, and the simulated results were compared with the measured data to verify the program. Also, influence of variation in the power control scheme on the operating characteristic and performance of the engine was simulated. The simulation program can be used for predicting operation of both healthy and degraded engine conditions.

• 한국항공우주학회지
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• 제39권10호
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• pp.959-965
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• 2011

본 논문에서는 소형 무인기의 전기추진 시스템에 대한 모델링 및 전력 시뮬레이션에 관하여 기술하였다. 각 전력원 모델링 및 시뮬레이션을 위해 Matlab/Simulink를 사용하였고, 연료전지와 배터리를 주 전력원으로 사용하는 200 W급 전기추진 시스템에 대하여 4시간 30분의 비행 시험결과와 시뮬레이션 한 결과를 비교하였다. 그 결과, 시뮬레이션은 각 전력원의 성능 및 동특성을 적절히 모사하였고, 이를 통해 다른 급의 전기추진 시스템에 대한 전력특성변화를 예측하는 도구로 활용 가능함을 알 수 있었다.

• 한국전자통신학회논문지
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• 제8권1호
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• pp.113-119
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• 2013

본 논문에서는 수 변전 설비의 열화진단을 위해서 열화상 카메라로 측정한 온도에 대한 시계열 데이터를 이용하여 포엔카레 맵과 프랙탈 차원에 의한 패턴 변화에 따른 온도 변화 특성을 살펴보았다. 시뮬레이션 결과 포엔카레 맵과 상관 차원에서 비선형적인 특성 거동을 확인할 수 있었다. 앞으로 추가적인 연구를 통한 검증 방법이 요구된다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 D
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• pp.1127-1129
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• 1997

In this paper, we developed to artificial neural network for load characteristic identification of power system. We can acquire active power and reactive power of individual load depending on the variation of voltage and frequency from the experimentation of a dynamic characteristic of load. The data of the experimental results were be used in learning of ANN. A proposed ANN model is applied to analyze the transient stability. To demonstrate the propriety of the power system transient stability with load model using ANN, the simulation of the two-machine five-bus system is carried out.

• 한국전자통신학회논문지
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• 제7권6호
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• pp.1443-1447
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• 2012

본 논문에서는 수 변전 설비의 열화진단을 위해서 열화상 카메라로 측정한 온도에 대한 시계열 데이터를 타켄스의 매립법을 이용하여 2차원 위상 공간으로 변환하여 패턴 변화에 따른 온도 변화 특성을 살펴보았다. 시뮬레이션 결과 위상 공간에서의 완전한 비선형적인 특성 거동을 확인할 수 없었지만 특정한 패턴을 가지고 있어 앞으로 추가적인 연구를 통한 검증 방법이 요구된다.

• 한국항공우주학회지
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• 제39권11호
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• pp.1052-1059
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• 2011

본 논문에서는 연료전지, 태양전지, 배터리를 동력원으로 사용하는 전기추진시스템의 전력특성변화에 대한 시뮬레이션에 관하여 기술하였다. 각 전력원을 통합하여 400 W급 전기 추진시스템에 대하여 모델링 및 시뮬레이션을 수행하였다. 그 결과 능동 제어로직이 없어도 배터리는 시동 및 과도상태에서 다른 동력원에 비해 빠른 출력반응을 보였으며, 연료전지와 태양전지는 순항영역에서 주 전력 공급원의 역할을 수행함을 확인하였다. 비행 후 동지때 SOC는 24.2%이고, 하지에는 93%로 시스템 안정성 확보 및 효율적인 동력분배 차원에서 적정 SOC를 유지하기 위하여 능동 전력제어가 필요함을 알 수 있다.

• 전기학회논문지
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• 제63권10호
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• pp.1467-1472
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• 2014

This paper study on powering characteristic on speed variation of propulsion system of prototype 8200 electric locomotive propulsion system through simulation modeling. For this purpose, it being applied in the field of railway IGBT (Insulated Gate Bipolar Transistor) elements are used. Converter was performed PLL (Phase-Locked Loop) control method that is used to control the phase and output voltage, and the inverter was carried an indirect vector control method to control the speed of traction motor. The results of simulation by modeling and experimental unit, we was confirmed that converter is controlled a unity power factor and output voltage by reference voltage. Also traction motor was controlled by indirect vector control and SVPWM inverter switching method very well.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.218-219
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• 2006

This paper is about modeling on 1500V DC electric railroad system. Electric railroad systems have peculiar characteristics against other electric system. The characteristics arc that the railroad systems have electric vehicle loads which are power-varying and location-varying with time. Because of this load characteristic, the electric railroad system modeling which reflects its own characteristics on EMTDC simulation could not be achieved. However, to reflect load characteristic on EMTDC, this paper suggests electric railroad system modeling by using TPS (Train Performance Simulator) that was developed in Korea Railroad Research Institute. A TPS program has various kinds of input data, such as operation condition, vehicle condition, and power system condition. By these data, TPS calculates mechanical power consumption and location, especially it decide electric power consumption on the basis of the fact that consumed electric and mechanical power are equal. Moreover, on this paper, movement of vehicle is reflected on EMTDC simulation as variation of feeder impedance. Also, an electric vehicle load is modeled as time-varying constant power load model.