• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.25 no.8
• /
• pp.88-98
• /
• 2011

Development and use of renewable energy due to environmental problems and depletion of energy affect grid-connected power system around the world. Therefore this paper analyzes the characteristic of gird connected photovoltaic power generation system which it is available to connect the utility. Renewable energy photovoltaic power system has been linked to the system to analyze the impact of photovoltaic system. MATLAB / Simulink program is modeled and analyzed on power quality of a photovoltaic power plant. It is measured that power data for the Grid connected photovoltaic power plant with instantaneous measuring, 3sec measuring, 10min measuring for 7 days. Harmonic field measurement have shown that the harmonic contents of a waveform varies with time. A cumulative probability approach is the most commonly used method to solve time varying harmonics. so, it is used 50[%] cumulative probability approach. This paper provides an in depth analysis on power quality field measurement of the Grid connected photovoltaic power plant.

• Journal of Electrical Engineering and Technology
• /
• v.12 no.5
• /
• pp.1689-1696
• /
• 2017

In recent academic and industrial circles of the Republic of Korea, the securement of available reactive power reserve against the line faults is at issue. Thus, simulations have been performed for the securing of effective reactive power reserve (effective Q) to prepare for the line faults and improve reactive power monitoring and control methods. That is, a research has been conducted for the fast-decoupled Newton-Raphson method. In this study, a method that distinguishes source and sink regions to carry out faster provision of information in the event of line fault has been proposed. This method can perform quantification with the formula that calculates voltage variations in the line flow. The line flow and voltage changes can be easily induced by the power flow calculation performed every second in the operation system. It is expected that the proposed method will be able to contribute to securement of power system stability by securing efficient reactive power. Also, the proposed method will be able to contribute to prepare against contingencies effectively. It is not easy to prepare quickly for the situation where voltage drops rapidly due to the exhaustion of reactive power source by observing voltage information only. This paper's simulation was performed on the large scale Korean power system in steady state.

• Journal of Power Electronics
• /
• v.12 no.1
• /
• pp.223-231
• /
• 2012

In this paper, criteria for better selection of a supercapacitor through EIS (Electrochemical Impedance Spectroscopy) experiments are presented. The performance characteristics of a supercapacitor are thoroughly analyzed in terms of losses and available energy to select the optimal product. The validity of the proposed criteria is demonstrated through the computer simulations and experiments on a fuel cell vehicle using a supercapacitor module with the FTP-72 urban dynamometer driving schedule.

• Proceedings of the KOR-KST Conference
• /
• 1996.06a
• /
• pp.95-128
• /
• 1996

Dipped track profiles between rail transit stations can significantly reduce propulsive energy, braking energy and travel times. This work quantifies their potential benefits for circumstances reflected in various values for dips, speed and acceleration limits, station spacings, and available power. A deterministic simulation model has been developed to precisely estimate train motions and performance using basic equations for kinematics, resistance, power and braking. For a dip of 1% of station spacing, in which gradients never exceed 4%, our results show savings (compared with level tracks) exceeding 9% for propulsive energy, 15% for braking energy and 5% for travel time between stations.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
• /
• 2002.02a
• /
• pp.43-45
• /
• 2002

High current density Bi-2223 tapes have recently become commercially available. There are some important characteristics of the tapes, e.g. critical current, ac loss, fault current characteristics, for an application such as a power cable or a power transformer. They have been investigated experimentally and discussed in this paper.

• Proceedings of the KIPE Conference
• /
• 2001.10a
• /
• pp.117-120
• /
• 2001

Resistance spot welding is widely employed in a manufacturing process. In recent years, the requirement for more sophisticated quality control procedures has been in the mass production industries. The requirements for high productivity and good welding qualities have lead to the development of more widely available microprocessor or computer based control. In this study, the inverter-type power source and welding servo gun are developed.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.5 no.2
• /
• pp.151-157
• /
• 1981

The concept of available evergy has been adopted in terms of effectiveness for and evaporator of vapor power cycle. This kind of practice is emphasezed in a case of heat and power cogeneration in order to find optimum condition for the energy utilzation of the exhaust gas. It has beed shown that the optimum condition can be given in terms of the saturation pressure or the saturation temperature of the working fluid. Similar method has been applide to show that the effectiveness is increased asymptotically with the number of evaporator stanges.

• Proceedings of the KIPE Conference
• /
• 2000.07a
• /
• pp.568-571
• /
• 2000

Resistance spot welding is widely employed in a manufacturing process. In recent years the requirement for more sophisticated quality control procedures has been in the mass production industries. The requirements for high productivity and good welding qualities have lead to the development of more widely available microprocessor or computer based control, In this paper the inverter-type power source and welding servo gun are developed.

• Proceedings of the KIEE Conference
• /
• 1992.07b
• /
• pp.676-684
• /
• 1992

The advent of inexpensive high power switching devices revived the interest in switched reluctance motor(hereafter referred to as SRM) drives. In the late 60's, the potential of SRM for traction application attracted researchers. Since then the progress in research of the SRM drive has been phenomenal. In this paper, a review of the basic principle of operation of the SRM, currently available converter topologies, the controller requirements and some design considerations are included.

• Proceedings of the KIEE Conference
• /
• 2005.07a
• /
• pp.778-780
• /
• 2005

Electric power industry throughout the world is restructured. The electric power industry has a characteristics of an oligopoly with an imperfect competition. In Korea rules, all information is not available. So the strategy under such incomplete information market differ firm those under complete information system in game theory. This paper presents a analysis technique if Korea ma rket model with incomplete information.