• Transactions on Electrical and Electronic Materials
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• v.18 no.5
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• pp.303-309
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• 2017

The flexible AC transmission system (FACTS) provides a new advanced technology solution to improve the flexibility, controllability, and stability of a power system. The unified power flow controller (UPFC) is outstanding for regulating power flow in the FACTS; it can control the real power, reactive power, and node voltage of distribution networks. This paper investigates the performance of the UPFC for power flow control with a series of step changes in rapid succession in a power system steady state and the response of the UPFC to distribution network faults and islanding mode. Simulation was carried out using the MATLAB's simulink sim power systems toolbox. The results, which were carried out on a 5-bus test system and a 4-bus multi-machine electric power system, show clearly the effectiveness and viability of UPFC in rapid response and independent control of the real and reactive power flows and oscillation damping [6].

• Proceedings of the KIEE Conference
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• 1998.07c
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• pp.1170-1172
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• 1998

The electrical power of nuclear power plant consists of Safety related power systems and Non-Safety related power systems. The safety related power systems are designed to have sufficient capacity to safely shut down the unit and to mitigate the effects of an accident assuming loss of off-site power. This paper presents the operation scheme of the safety related power system for several plant conditions in Korean Next Generation Reactor and reviews the diversity of power supply to the safety related bus.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.1
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• pp.92-98
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• 2013

There are lots of studies about hybrid electric vehicles (HEVs) because of the global warming and energy problems. Series and parallel HEVs are the common types of many developing hybrid vehicle types. Series HEV uses engine only as the generator for the battery but parallel HEV utilizes engine for driving and generating of the vehicle. In this paper, backward simulations based on dynamic programming were conducted for the fuel economy analysis of two different types of hybrid transit buses depending on driving cycles. It is shown that there is a relation between the type of HEV and the characteristics of driving cycles. Regarding the aggressiveness, the series hybrid bus is more efficient than the parallel system on highly aggressive driving cycle. On the other hand, the parallel hybrid bus is more efficient than the series system on low aggressive driving cycle. Based on this results of the paper, it is expected to choose more efficient type of the hybrid buses according to the driving cycle.

• Journal of Electrical Engineering and Technology
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• v.12 no.5
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• pp.1743-1753
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• 2017

Since there are multiple random variables in the probabilistic load flow (PLF) calculation of distribution system containing distributed generation (DG) and electric vehicle charging load (EVCL), a Monte Carlo method based on composite sampling method is put forward according to the existing simple random sampling Monte Carlo simulation method (SRS-MCSM) to perform probabilistic assessment analysis of voltage quality of distribution system containing DG and EVCL. This method considers not only the randomness of wind speed and light intensity as well as the uncertainty of basic load and EVCL, but also other stochastic disturbances, such as the failure rate of the transmission line. According to the different characteristics of random factors, different sampling methods are applied. Simulation results on IEEE9 bus system and IEEE34 bus system demonstrates the validity, accuracy, rapidity and practicability of the proposed method. In contrast to the SRS-MCSM, the proposed method is of higher computational efficiency and better simulation accuracy. The variation of nodal voltages for distribution system before and after connecting DG and EVCL is compared and analyzed, especially the voltage fluctuation of the grid-connected point of DG and EVCL.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.11 no.2
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• pp.52-57
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• 2012

In this paper describe configuration about QCM system for image processing device. It presents that QCM's image processing board video from the camera recognized by the PLC's battery removable exact location coordinates to the robot image processing technology to deliver. In addition, QCM video image processing technology for improved data reliability is described. In this paper define the landmarks of battery for obtaining the location coordinates and verify battery the location coordinates acquisition process from field tests of the QCM/QTPE-BUS Battery Exchange System.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1836-1839
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• 2005

We have developed Ethernet based real-time communication systems called "Vnet/IP" for DCS which is the control system for process automation. This paper describes the features and the technologies of the ASIC which is utilized in the communication interface hardware for Vnet/IP. Vnet/IP has been developed for mission-critical communications. Hence it has real-time feature, high reliability and precise time synchronization capability. At the same time, it is able to deal with standard protocols without influence on mission-critical communications. The communication interface hardware has a host interface and dual redundant network interfaces. The host interface can be chosen PCI-bus or R-bus which is the proprietary internal bus developed for the high reliable redundant controller. Each network interface is a RJ45 connection with 1Gbps maximum in compliance with IEEE802.3.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.298-299
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• 2008

In this paper, supposed that can measure power quality of bus and can calculate this cost in case electric charges about customer are imposed by each bus. When reflected this in system planning, expected cost proposed following method through sample system. We calculated the nodal cost by OPF(optimal power flow) in system and the drop numbers that happen during year of loads utilizing VSCC. Also calculated BPQC using the disruption numbers. As a result, calculated bus total cost including power quality cost through case study.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.39 no.2
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• pp.133-141
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• 1990

In the operation of an electric power system, the voltage security of the system has acquired more significant importance after the occurrence of large system black-outs caused by voltage collapse several times. This paper describes a fast contingency screening method concerning voltage security. The method defines a voltage-sensitive buses where significant voltage changes would occur as a result of the contingency to reduce the number of bus voltages to be solved for continngency screening. This method is based on the observation that it is not necessary to solve the entire network in most contingency cases because boltage changes actually occur around the contingency. The P-Q decoupled linearized model and the fast error correction method are also adopted in the method to define voltage-sensitive buses and to calculate voltage magnitude on the selected voltage-sensitive buses fastly and reliably. The method suggested in this papaer has been tested in IEEE 30-bus model system and KEPCO 130-bus actual system and its effectiveness for practical use has also been confirmed.

• Journal of Electrical Engineering and Technology
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• v.2 no.2
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• pp.194-200
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• 2007

The deregulation problem has recently attracted attentions in a competitive electric power market, where the cost must be earmarked fairly and precisely for the customers and the Independent Power Producers (IPPs) as well. Transmission loss is an one of several important factors that determines power transmission cost. Because the cost caused by transmission losses is about $3{\sim}5%$, it is important to allocate transmission losses into each bus in a power system. This paper presents the new algorithm to allocate transmission losses based on an integration method using the loss sensitivity. It provides the buswise incremental transmission losses through the calculation of load ratios considering the transaction strategy of an overall system. The performance of the proposed algorithm is evaluated by the case studies carried out on the WSCC 9-bus and IEEE 14-bus systems.

• Journal of the Korean Institute of Gas
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• v.24 no.2
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• pp.9-14
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• 2020

This paper is a purpose to study the failure examples for a large bus vehicle fire. The first example, the researcher certified the fact that the absorbing material break away from the upper side of engine room because of weaken durability and the fire was produced in engine. The second example, it sought the fact that the fire breaks out by electric short because of over-load of compressor. The third example, it found the fact that the fire took place by heating of bellows upper part that was connected with muffler and exhaust manifold. The fourth example, it knew the fact that the fire occurred because of the electric short inside junction box of crash body part that was located to driver seat rightside. Therefore, the fire of a large bus occurring by decrepit of absorbing material and electric short have to thoroughgoingly manage the damage and dangerousness if it happens.