• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1894-1895
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• 2007

It is excitation system for nuclear emergency generator that is to startup automatically and sequentially supply essential loads with power. There are static type and alternating exciter, etc in its excitation system. An object of study is static excitation system which power is taken from power potential transformer and power current transformer. It is to complement curtailment of excitation system ability at happening short accidents. And Startup mode are quick startup and slow startup, etc. Its characteristic is looked into in this paper.

• Journal of Power System Engineering
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• v.17 no.4
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• pp.31-35
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• 2013

The emergency AC power supply system of the nuclear power plant is designed to supply the power to the nuclear power plant at the emergency operating condition. The safety function of the diesel generator at the nuclear power plant is to supply AC electric power to the safety system whenever the preferred AC power supply is unavailable. The reliable operation of onsite standby diesel generator should be ensured by a condition monitoring system designed to maintain, monitor and forecast the reliability level of diesel generator. The purpose of this paper is to improve the existing ultrasonic sensor used for condition diagnosis of engine fuel pump and cylinder head for the accurate diagnosis in actual engine condition of emergency diesel generator(EDG). As a result of this study, we could design and develop much more reliable ultrasonic sensor than existing ones.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2006.03a
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• pp.479-486
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• 2006

This paper presents tile results of experimental studies of the isolated Model EDG Systems. For the experimental work, the scaled model of EDG system and the isolation systems were developed. The target EDG model is 16PC2-5V400 which was manufactured by the SEMT Pielstick corporation. The Coil Spring and Viscous Damper Systems were selected for the isolation system. The Coil Spring and Viscous Damper systems can reduce not only seismic forces but also the operating vibration. For the input seismic motions, the scenario earthquake and the artificial earthquakes which were developed as NRC design spectrum and Uniform hazard Spectrum(UHS) were selected. As a result, at least 20% of seismic forces were decreased as the isolation system.

• Proceedings of the KIPE Conference
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• 2018.11a
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• pp.119-120
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• 2018

국내 원자력 발전소의 비상전원공급을 위하여 대체교류디젤 발전기와 납축전지를 사용하고 있다. 납축전지는 온도, 방전 전류, 수명 및 안정성 등에서 리튬계열전지와 비교되고 있으며, 전기적 특성이 우수하고 안정성이 높은 리튬계열전지의 사용이 고려되고 있다. 본 논문은 원전의 비상전원 설계를 위하여 납축전지와 리튬계열전지의 전기적 특성을 비교 분석하였다.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.11
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• pp.1271-1276
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• 2015

The recent trend is that diesel power generation on islands where its prime cost for power generation is high is replaced by new and renewable energy. Therefore, south Jeolla province is progressing the construction project of self-sufficient islands for the areas where power is supplied by depending on diesel generators, which is the project that power is supplied through eco-friendly energy source using sunlight, wind power and energy storage device etc. However, it is difficult to construct new and renewable energy source with the capacity to respond to the load perfectly due to its environmental and geographical conditions regarding capacity design of new and renewable energy. Besides, Microgrid design considering appropriate capacity design of the system components and efficient operation is required through the analysis of climate conditions and load patterns from the design stage for optimal composition of a hybrid system with economic feasibility. Therefore, this study is aimed to conduct a research on optimal combination, capacity calculation and economic feasibility by comprising a hybrid power generation system which will replace 40% of power generation by diesel as new and renewable energy source for Geomun Island where has more than 300 households and requires expansion of the facility among islands located in southwest coast.

• The Transactions of the Korean Institute of Power Electronics
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• v.23 no.2
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• pp.86-93
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• 2018

In this work, control methods and operating modes are proposed to manage standalone microgrid. A standalone microgrid generally consists of two sources, namely, battery energy storage system (BESS) and diesel generator (DG). BESS is the main source that supplies active and reactive power regardless of load conditions, whereas DG functions as an auxiliary power source. BESS operates in a constant voltage constant frequency (CVCF) control, which includes proportional-integral + resonant controller in a parallel structure. In CVCF control, the concept of fundamental positive and negative transformation is utilized to generate a three-phase sinusoidal voltage under imbalanced load condition. Operation modes of a standalone microgrid are divided into three modes, namely, normal, charge, and manual modes. To verify the standalone microgrid along with the proposed control methods, a demonstration site is constructed, which contains 115 kWh lead-acid battery bank, 50 kVA three-phase DC - AC inverter, and 50 kVA DG and controllable loads. In the CVCF control, the total harmonic distortion of output voltage is improved to 1.1% under imbalanced load. This work verifies that the standalone microgrid provides high-quality voltage, and three operation modes are performed from the experimental results.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.1
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• pp.81-86
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• 2013

Exhaust gas from a small portable electric generator is simply exhausted to the surroundings because the capacity and quality of the waste heat of this gas is generally not sufficient to recover and utilize. We have proposed a seawater distiller utilizing the thermal energy of waste gas from an electric generator. The distiller recovers heat from the waste gas by means of a heat pipe and uses it effectively through a multiple-effect diffusion-type structure. We constructed an experimental apparatus with a vertical single-effect still having a 4-stroke 50 cc generator engine and found that the experimental results for distillate productivity show good agreement with the theoretical predictions. The results show that the distiller can recover 52 W of waste heat from the gas at $171^{\circ}C$, and ~85% of the recovered heat can be utilized for distillation to produce 70 g/h of fresh water. This is equivalent to a productivity of 500 g/h in the case of a 10-effect still. Therefore, the proposed distiller should be useful in remote areas where electricity and water grids are inadequate.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.04a
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• pp.504-508
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• 2009

To obtain high power, diesel engines continuously increase combustion pressure and mean effective pressure each cylinder, and the excitation sources and noisy sources are increased, too. Moreover, to reduce the costs, shipyards make hull structures weaker than before. As above reasons, it is more difficult to control the vibration phenomenon nowadays. In this study, it was investigated why diesel generator sets reached the vibration allowable limits during the FAT and heavy vibration phenomenon of diesel generator sets using ODS test during onboard tests. Also, it is found out the stiffness of deck and common bed using the test result of their structural impedance. To find out the vibratory characteristics of diesel generator sets, MODAL tests were carried out. From the sensitivity analysis after above tests, it was selected points to be reinforced and studied troubleshooting to solve heavy vibration phenomenon of diesel generator sets.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.54 no.11
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• pp.561-568
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• 2005

This paper proposes a method that distributes the load power and stores the regenerated energy for a hoist-load system using the supercapacitor, an energy storage device. The crane, which is a representative hoist-load system, operates in two modes. The first is the hoist-up mode in which the load container is lifted up: the maximum power is required at the end of acceleration. The second is the hoist-down mode in which the load container is lifted down; the regenerated energy is wasted by the resistor In this paper, the supercapacitor stores the regenerated energy in the hoist-down operation and supplies the peak power demand in the hoist-up operation. The same structure as the commercially available three-phase inverter is proposed as a bidirectional do-dc converter to charge and discharge the supercapacitor. A power control algorithm is proposed to optimize the load sharing between the generator and the supercapacitor. Using the proposed method, it is effected that the generator size can be cut down to one third of the original one; it leads to the reduction of the fuel consumption, noise and air pollution. Simulation and experimental results verify the effectiveness of the Proposed method.

• Journal of The Korean Society of Agricultural Engineers
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• v.59 no.1
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• pp.109-116
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• 2017

Biomass gasification produces syngas or producer gas as low calorific fuel gas that can be used as a fuel for combustion or prime movers as well as chemical synthesis. Internal combustion engines are readily available with lower costs and easily used for producing distributed power using biomass syngas. In this study, a dual fuel diesel engine was used to evaluate its performance when biomass syngas is used for fuel. The engine was originally developed for biogas application with a diesel engine with a 2,607 cc displacement. Both diesel fuel and syngas consumptions were observed at the different load conditions. The results indicate that the dual fuel engine showed a reasonably good performance and up to 63 % of diesel fuel saving.