• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.611-614
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• 2009

The present paper relates to an integration power system combining tidal power generation and ocean current power generation, and more particularly, to an integration power system combining a tidal power plant and two ocean current power parks, which is capable of increasing the operating rate of power facilities and efficiently generating electrical energy by using incoming seawater into the lake through turbine generators of a tidal power plant or fast flow of seawater discharged to a sea side through sluice gates of a tidal power dam. It is shown that the integration power system is a new promising ocean power system and the ocean current turbine generators in the ocean current power parks of the integration power system are smaller in size and larger in power generation capacity compared with the tidal current turbine generators in the ocean.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.270-273
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• 2008

The integrated power system combining a tidal power plant and two ocean current power parks is suggested. It is characterized by the set up of an ocean current power park in the lake side by installing a number of ocean current turbines generating electricity by using sea water flow discharged into the lake side from the turbine generator of a tidal power plant and an ocean current power park in the sea side by installing a number of ocean current turbines generating electricity by using sea water flow exiting into the sea side through the sluice gate from the lake side. The vision of the integrated power system is demonstrated by the simple theory and simulation results of the SIWHA Tidal Power Plant. And it is shown that the newly proposed integrated power system combining tidal power and ocean current power can produce very high economical benefits.

• Journal of Navigation and Port Research
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• v.35 no.8
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• pp.637-641
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• 2011

Ocean structure's power system is difficult to construct a stand-alone power system. Therefore, to manage effectively power system of ocean structure, it's important to construct power system which is connected fuel-cell with hybrid power system. This paper designs power system of fuel-cell for the sea based on hydrogen generation mechanism, calculation of using electric power, etc. Designed power system is analysed & simulated using LabVIEW program. And, this paper suggests design method of power system for ocean structure based on analysed & simulated results.

• Journal of Ocean Engineering and Technology
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• v.35 no.1
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• pp.1-12
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• 2021

As increasing the international community's awareness of greenhouse gas reduction, the demand for eco-friendly ship fuel has accelerated recently. The fundamental aim of this study is to develop a new type of fully electrified ferry for passengers and cars considering Korean domestic coastal environmental conditions. Several technical difficulties are encountered in applying a fully electric propulsion system based on removable battery systems into a ship due to limitations imposed by the batteries' size and capacity. This paper reviews and analyzes marine environment regulations strengthened recently, technology trends related to fully electric propulsion vessels in each country, and Korean domestic coastal environments. We propose a new fully electrified car ferry design with a displacement of 400 t applied in Korea. It is powered by removable battery systems pre-charged in a safe inland charging station. The mobile battery system is developed to enable roll-on and roll-off using wheels. The characteristics of the ship motion are analyzed based on the weight and location of the battery systems. We expect our battery systems to be applicable to larger ships in the future.

• Journal of Ocean Engineering and Technology
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• v.30 no.1
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• pp.1-9
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• 2016

In order to convert wave energy into large quantities of high-efficiency power, it is necessary to study the optimal converter system appropriate for the environment of a specific open ocean area. A wave energy converter system with a counterweight converts the translation energy induced from the heave motion of a buoy into rotary energy. This experimental study evaluated the primary energy conversion efficiency of the system, which was installed on an ocean generating basin with a power take-off system. Moreover, this study analyzed the energy conversion performance according to the weight condition of the buoy, counter-weight, and flywheel by changing the load torque and wave period. Therefore, these results could be useful as basic data such as for the optimal design of a wave energy converter with a counterweight and improved energy conversion efficiency.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2011.10a
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• pp.75-75
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• 2011

This paper has been studied that ocean wave vibration power generator is composed of buoy and vibration generator to make effective use of ocean wave energy. We designed buoy to can occur resonance for dominant frequency with ocean wave. And then we fitted the natural frequency of vibration system with vibration power generator to buoy's natural frequency. And we can show that the amplitude of ocean wave up and down motion is decreased, on the other hand, the displacement of vibration system with vibration power generator is increased. Therefore, ocean wave vibration power generator which is proposed in this paper has merits not only securing its stability from surroundings but also producing more electronic power by using ocean wave energy.

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.8
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• pp.1028-1034
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• 2011

This paper have been studied that ocean wave power vibration generation system with two D.O.F.(degree of freedom) consists of buoy and vibration generation system with two D.O.F. for using efficiency of ocean wave energy. It selected main frequencies ${\omega}_1$, ${\omega}_2$ in frequency with ocean wave and it fitted them to the natural frequencies of vibration system with two D.O.F. in the vibrational power generation system. Then each the relative velocity of between the winding coil and the permanent magnet is faster than the velocity of ocean wave up and down motion by resonance phenomenon. Also the ocean wave power generation with two D.O.F. obtained the more electric energy then the ocean wave power generation with one D.O.F. by coupling effect for two D.O.F. vibration system. Therefore ocean wave power vibration generation system with two degree of freedom that is proposed in this paper has merits which not only using more energy in the ocean wave but also obtaining more electronic energy.

• Journal of Advanced Research in Ocean Engineering
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• v.1 no.3
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• pp.176-185
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• 2015

Recently, focus has been placed on ocean energy resources because environmental concerns regarding the exploitation of hydrocarbons are increasing. Tidal current power, one of the ocean energy resources, has great potential worldwide due to its high energy density. The flow velocity is the most crucial factor for the power estimation of TCP(Tidal Current Power) system since the kinetic energy of the flow is proportional to the cube of the flow speed. So sufficient inflow speed to generate electricity from the tidal current power is necessary. A duct system can accelerate the flow velocity, which could expand the applicable area of TCP systems to relatively lower velocity sites. The shapes of the inlet and outlet could affect the flow rate inside the duct. To investigate the performance of the duct, various ducts were preliminary designed considering the entire system that is single-point moored TCP system and a series of simulations were carried out using ANSYS-CFX v13.0 CFD software. This study introduces a ducted turbine system that can be moored to a seabed. A performance estimation and comparison of results with conventional tidal converters were summarized in this paper.

• The KSFM Journal of Fluid Machinery
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• v.12 no.3
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• pp.38-43
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• 2009

The Shiwhaho is an artificial lake located in Yellow sea of Korea where the ocean tidal current is significantly strong, and the tidal power plant is currently being under construction to generate electric power from the ocean tidal current. In addition to the tidal power plant under construction, an ocean current power park was proposed to maximize the power generation by utilizing the ocean current generated by the tidal power plant. To evaluate the feasibility of such combined power plant, the flow characteristics in the ocean current power parks connected with the tidal power plants were investigated numerically in the present study. When two different type of generations are operating together as a system, their interference may occur, which affects their efficiency. Therefore, the minimum distances between the tidal power plants and the ocean current power generators are studied in the present study to minimize such interference. The feasible region to generate power around the Shiwha tide embankment is also predicted by considering predicted ocean current speed distribution. Various arrangements of the ocean current generators are examined and an optimal arrangement is also discussed.

• Journal of Navigation and Port Research
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• v.33 no.6
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• pp.381-385
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• 2009

Generally power system of ocean facility composes a solar generation system.The power to be generated by the solar system is changed according to the amount of sunlight of weather conditions. Output power of solar system is decreased with weather condition such as cloudy day and rainy day. And the power shortage of the ocean facility can occur due to the lack of solar energy. To solve this problem, this paper proposes the power control system for solar-wave hybrid system Wave generation system consists of wells turbine and permanent magnet synchronous generator(PMSG). This propose system set the specific area and measures the solar generation power and wave generation power. As a result of experiment, the solar power is a more static source than wave power, but the wave power provides energy during periods of no sunshine. The power characteristic of propose hybrid system have been obtained high reliability than a solar generation system.