• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.4
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• pp.748-757
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• 2007

This paper is intended to solve the technical problem that fails in large-capacity induction motor starting due to serious voltage drop during starting period. One induction motor that is established already can reach in steady-state using reactor starting method but the voltage magnitude of PCC (point of common coupling) has dropped down a little. When the same capacity induction motor is installed additionally in the PCC, where the existing induction motor is operating, voltage drop becomes more serious by starting of additional induction motor. As a result, the additional induction motor fails in starting. Therefore, voltage compensation method is proposed so that all of two induction motors can be started completely. First, modeling technique is described in order to implement starting characteristics of large induction motor. And then, this paper proposes strategic starting scheme by proper voltage compensation that use no-load transformer tap control (NLTC) and step voltage regulator (SVR) for starting of two large induction motors successfully and improving the feeding network voltage profile during the starting period. The induction motor discussed in this paper is the pumped induction motor of 2500kVA capacity that is operating by KOWACO (Korea Water Resources Corporation). Modeling and simulation is conducted using PSCAD/EMTDC software.

• Proceedings of the KIEE Conference
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• 2006.11a
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• pp.411-413
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• 2006

This paper presents a novel fault location scheme on Korean AC electric railway systems. On AC railway system, because there is a long distance, 40 km or longer, between two railway substations, a fault location technique is very important. Since the fault current flows through the catenary system, the catenary system must be modeled exactly to analyze fault current magnitude and fault location. In this paper, before suggestion for the novel scheme of fault location, a 9-conductor modeling technique that includes boost wires and impedance bonds is introduced, based on the characteristics of Korean AC electric railway. After obtaining a 9-conductor modeling, the railway system is constructed for computer simulation by using PSCAD/EMTDC. By case studies, we can verify superiority of a new fault location scheme and suggest a powerful model for fault analysis on electric railway systems.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.5
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• pp.760-768
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• 2016

Recently, as one of the policies for carbon free operation method of independent power system replacing diesel generator with renewable energy such as wind power and photovoltaic(PV) system has been presented. Therefore, this paper proposes an operation algorithm and modeling of independent power system by considering CVCF(constant voltage constant frequency) ESS(energy storage system) for constant frequency and voltage, LC(load control) ESS for demand and supply balancing and SVC(static var compensator) for reactive power compensation. From the simulation results based on the various operation scenario, it is confirmed that proposed operation algorithm and modeling may contribute stable operation and carbon free in independent power system.

• Proceedings of the KIEE Conference
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• 2007.11b
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• pp.180-181
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• 2007

In this paper, SFCL using two magnetically coupled coils was modeled and simulated by PSCAD/EMTDC. The simulation was shown that fault current could be adjusted with the inductance ratio and the winding direction of two coils. The limited fault current in case of the additive polarity winding was lower than that of the subtractive polarity. The analysis results were compared with the calculated ones, and both the results agreed.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2005.05a
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• pp.92-94
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• 2005

In this paper, when electric train is in dead-section the effect on electric train system was dealt. The feeding system of electrical railway is AC or DC. When the electric train is passed AC feeding system to DC, vice versa or phase is changed in between AC feeding systems, there is a dead section. A dead section usually makes the electrical system complex md may have an adverse effect on the electrical system inside the train. Accordingly, it is important to analyze the effect on trains in dead-section. Modeling an electric train and simulation using PSCAD/EMTDC was accomplished to analyze how power quality problem such as inverter switching surge is propagated to electric train through the feeding line, railway, pantograph.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.7
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• pp.1211-1217
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• 2007

In this paper, a 10kVA PV inverter applying Incremental Conductance(IncCond) method for maximum power point tracking WIS developed and its performance tests were carried out. Modeling and simulation of PV array and system controller was performed using PSCAD/EMTDC, an electromagnetic transient analysis program. After comparison and analysis of Perturbation & Observation (P & O) and IncCond method, a PV inverter based on IncCond method was designed and manufactured. Grid interface transient characteristics including start-up, normal operation, and fault operation were tested, which verified the usefulness of the proposed system. In the near future, commercialization process will proceed through additional extensive tests of transients.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.147-148
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• 2006

Recently, due to increasing the application of power electronic equipment, harmonics generated from the non-liner load are fairly produced. Harmonics can cause a variety of problems such as the overheating of distribution transformer, the breakdown of device and communication interference. Interest about power quality decline of power system is very increased. In this paper, we are measured the harmonic voltage and current o( power system to analyze harmonic characteristics, and it is analyzed Total Harmonic Distortion(THD). Also, we Ere modeled power system using PSCAD/EMTDC. And it is analyzed harmonic voltage and current in steady-state. The study results have been indicated the utility about harmonics analysis and modelling for power system.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.533-534
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• 2006

Micro-source units having power ratings in thousands of watts can provide power quality with higher reliability and efficiency than the conventional large scale units. This paper develops switching level model of micro-source and studies the characteristics of the micro-grid consisting of multiple micro-sources and interfaced with electric power system. The developed model adopts the space vector PWM to fully utilize the capacity of inverter. The interaction of the grid connected micro-sources and the characteristics of the control system parameters are investigated. Micro-sources and micro-grid are implemented using PSCAD/EMTDC. Simulation results show that the proposed model is efficient for studying micro-grid system.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.51-53
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• 2005

At the railway feeding system, a role of dead section is very important. Because, dead section is essential installation that AC feeding system meets DC feeding system or phase is changed between AC feeding systems. But, in dead section it is possible that an electric train meets interruption. In Korea, a study on the dead section isn't yet accomplished in depth. Accordingly. In this paper, when electric train is in dead-section power quality problem on electric train was dealt. Modeling and simulation using PSCAD/EMTDC was accomplished to analyze.

• KIEE International Transactions on Power Engineering
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• v.3A no.4
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• pp.206-213
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• 2003

The main purpose of this paper is to present a simulation model for assessing the impacts of a variable speed wind turbine (VSWT) on the distribution network and perform a simulation analysis of voltage profiles along the wind turbine installed feeder using the presented model. The modeled wind energy conversion system consists of a fixed pitch wind turbine, a synchronous generator, a rectifier and a voltage source inverter (VSI). Detailed study on the voltage impacts of a variable speed wind turbine is conducted in terms of steady state and dynamic behaviors. Various capacities and different modes of variable speed wind turbines are simulated and investigated. Case studies demonstrate how feeder voltages are influenced by capacity and control modes of wind turbines and changes in wind speed under different network conditions. Modeling and simulation analysis is based on PSCAD/EMTDC a software package.