• International Journal of Fluid Machinery and Systems
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• v.5 no.4
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• pp.174-179
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• 2012

A numerical study to investigate the effect of intake vortex occurrence on the performance of an axial hydraulic turbine for generating tidal power energy in Sihwa-lake tidal power plant, Korea, is performed. Numerical analysis of the flow through an sxial hydraulic turbine is carried out by solving three-dimensional Reynolds-averaged Navier-Stokes dquations with the shear stress transport turbulence model. In the real turbine operation, the vortex flows are occurred in both the side corners around the intake of an axial hydraulic turbine due to the interaction between the inflow angle of water and intake structure. To analyze these vortex phenomena and to evaluate their impacts on the turbine performance, the internal flow fields of the axial hydraulic turbines with the different inflow angles are compared with their performances. As the results of numerical analysis, the vortex flows do not directly affect the turbine performance.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.505-508
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• 2006

Recently, concern for tidal power is being increased by newly recycled energy. It is important to decide on the maximum power estimate operation and it's stop by applying the difference of water level between tide level and artificial reservoir for the administration of tidal development. For maximum output of power through turbine generator, administrative variables and process on efficiency of hydraulic turbine and inflow discharge of reservoir is quite complicated because it is run through the connection of discharge-gate and turbine On the development of this model, the administrative process is decided, Operation block is presented for it's maximum power estimate.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.63 no.2
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• pp.89-94
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• 2014

Tidal generation has become one of environmentally friendly new and renewable future sources of energy. The Sihwa Tidal Power Plant in South Korea, which was imported from abroad by turnkey type in 2011, connected to the power system in 2012, and is currently under commercial operation. However, leading companies are reluctant to disclose their technologies associated with the control systems and are not cooperative in technology transfers, making it a high priority to develop core technologies in South Korea. In order to develop a start stop control system for tidal generation, this paper presents the optimal algorithm for decision making and prototype of hardware design. First, control systems in tidal power, such as plant operation control, data interfaces between systems, monitoring and control points of the control system, are analyzed. The software development and PC based emulator processes for optimization algorithm processing are described. Finally, verification of the algorithm implementation, hardware platform for start stop control device, and implementation of prototype control system were discussed.

• International Journal of Ocean System Engineering
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• v.1 no.3
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• pp.144-147
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• 2011

The rotor that initially converts the flow energy into rotational energy is a very important component that affects the efficiency of the entire tidal current power system. Rotor performance is determined by various design variables. Power generation is strongly dependent on the incoming flow velocity and the size of the rotor. To extract a large quantity of power, a tidal current farm is necessary with a multi-arrangement of devices in the ocean. However, the interactions between devices also contribute significantly to the total power capacity. Therefore, rotor performance, considering the interaction problems, needs to be investigated to maximize the power generation in a limited available area. The downstream rotor efficiency is affected by the wake produced from the upstream rotor. This paper introduces the performance of a downstream rotor affected by wakes from an upstream rotor, demonstrating the interference affecting various gabs between devices.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.610-613
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• 2009

Uldolmok tidal current power plant was constructed on May 2009 at Jindo Gun in Korea. However it had much trouble in installing structure due to the extremely fast tidal current velocity(max. 5.5m/sec) and the jacket type plant structure. Therefore in this paper, The characteristics of tidal current and sea bed topography at Uldolmok tidal current plant site are investigated, and the detailed foundation work process of the plant is described.

• Journal of Electrical Engineering and Technology
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• v.10 no.6
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• pp.2271-2276
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• 2015

A superconducting synchronous generator (SCSG) can be expected to decrease the size and weight compared to conventional tidal current generators. This paper proposes an optimal design of a 2 MW class SCSG for a tidal current power generation system. The proposed optimal design of the SCSG will reduce the length of the high-temperature superconducting wire as well as the weight and volume of the SCSG. The 3D finite element method is used to analyze the magnetic field distribution. The optimized 2 MW SCSG is compared with a 2 MW conventional generator. As the optimized SCSG is more compact and lighter than a conventional generator, it will be efficiently applied to practical tidal power systems.

• Journal of the Korean Solar Energy Society
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• v.29 no.5
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• pp.73-80
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• 2009

A tidal current turbine is designed and analyzed numerically by using blade element momentum theory. The rated power has a limitation because the diameter of the tidal current turbine cannot exceed the depth of sea water. This study investigates a horizontal axis tidal-current turbine with a rated power of 500 kW. NACA-6 series laminar foil shape is used for basic airfoil along the blade span. The distributions of chord length and twist angle along the blade span are obtained from the hydrodynamic optimization procedure. Prandtl's tip loss correction and angle of attack correction considering the three-dimensional effect are applied for this study. The power coefficient curve shows maximum peak at the rated tip speed ratio of 6.0, and the maximum torque coefficient is developed at the tip speed ratio of 4. The drag coefficient reaches about 0.85 at the design tip speed ratio.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.31 no.6
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• pp.379-385
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• 2019

Dynamic Tidal Power, which is a kind of tidal power generation, requires huge structures, because it is conducted by using the phase difference caused by the diffraction effect of tides. Economic feasibility is most demanded for practical use, and various studies have been conducted for this purpose. In this study, unlike existing methods, several structures were installed to improve it by increasing power generation. The flow changes around the structures were studied, and it was found that proper spacing between structures was necessary for efficient power generation.

• New & Renewable Energy
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• v.9 no.4
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• pp.19-24
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• 2013

In order to analyze the characteristics of tidal current power generation system, we measured output power in M-G Set (Motor-Generator Set) and MATLAB/Simulink. We installed M-G Set (Motor-Generator Set) and did a simulation using MATLAB/Smulink. The simulation consisted of the tidal current turbine, PMSG, converter, and three-phase PWM inverter. Also, the speed control of the generator was performed using machine side converter. And we measured output voltage, current, power of the generator and the output power of three-phase PWM inverter.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.159.2-159.2
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• 2011

Hyundai Heavy Industries has developed a tidal current energy converter utilizing the accumulated technology as the world largest constructor for ship and offshore structures. The model has two sets of turbines in both ends in order to utilize the bi-directional current flows in flood and ebb tide. The torque produced by turbine in tidal current is directly delivered to generator along the horizontal axis, in which the turbine, gear, generator, gear and turbine are connected successively. The manufactured model for field test has the turbine diameter of 5 meters to produce the maximum power of 500kW at maximum current speed of 5m/s. The technical verification of tidal power converter was performed by means of small scale model test in towing tank as well as field test at the Strait of Uldolmok located in Jindo of Jeollanamdo province. Field test was performed by mounting the tidal current converter on the SEP(Self Elevating Platform) which could lower the 4 vertical legs on the seabed and could elevate platform over the water surface using the hydraulic power for itself. The field test performed for a month shows that power output is similar or larger compared with the expected one in design stage. This paper presents the development of tidal current energy converter and real sea field test by Hyundai Heavy Industries. This project has finished successfully and provided the technical advance toward commercial services for tidal current power generation in the south-west region in Korea.