• 한국전산유체공학회:학술대회논문집
• /
• 2008.03b
• /
• pp.180-183
• /
• 2008

This paper is about the ocean current power generation using sea water incoming into the lake surrounded by barrages and sea water discharged from a dam made of artificial structures. In operation of a tidal power plant, the sea water discharged from a turbine structure and a gate structure of a tidal power plant is faster than the tidal current caused by tides in nature and has better characteristics than that to run ocean current turbines. It is shown that the sea water discharged after generating electricity through a turbine generator of a tidal power plant and the sea water discharged from a gate structure of a tidal dam still have kinetic energy high enough to run an ocean current turbine and produce valuable electricity.

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

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

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

• 한국신재생에너지학회:학술대회논문집
• /
• 2010.06a
• /
• pp.235.1-235.1
• /
• 2010

Two ocean current power parks are suggested in the front and back of the Garyuk draining sluices of Saemankeum in Korea. They are characterized by installing a plurality of ocean current turbine generators which are arranged in five rows respectively in the land-side ocean current power park behind the Garyuk draining sluices and in the sea-side ocean current power park before the Garyuk draining sluices, generating electricity using the ocean current flowing through the Garyuk draining sluices in the ebbs and tides of Yellow sea. The potential energy of tidal difference of 2.611m at neap in Saemankeum can be converted into the kinetic energy of high speed ocean current via the Garyuk draining sluices which makes it possible to run the ocean current power parks on a large scale. The total facility capacity of two ocean current power parks that consist of 240 ocean current turbine generators with 4m diameter of turbine blades is about 134MW, and the expected total annual power output is about 586GWh.

• 한국신재생에너지학회:학술대회논문집
• /
• 2011.11a
• /
• pp.160.2-160.2
• /
• 2011

바다를 가로막는 방벽이나 방조제의 배수갑문 또는 조력발전소의 수문과 같이 인공 해양구조물을 통하여 흐르는 고속 해류를 이용하여 발전하는 해류발전 방식에 있어서, 고속 해류에 적합한 수차터빈과 발전기의 특성을 알아보았다. 조석간만의 차가 큰 지역에 설치되는 인공 해양구조물을 지나는 해류는 인공 해양구조물 전후에 발생하는 해수의 위치에너지 차이가 운동에너지로 바뀌면서 조석간만의 자연현상에 의해 발생되는 조류의 속도보다 훨씬 더 빠르게 흐른다. 이론적으로 우리나라의 서해안의 조석간만의 범위 3~8m로부터 7.5~12m/s 정도의 고속 해류가 가능하다. 이러한 경우에 적합한 해류발전기는 수차터빈 날개지름의 크기가 5m에서부터 12m 이하이면서, 증속기어박스와 발전기, 유압시스템 및 냉각시스템 그리고 전력변환장치를 포함하는 발전시설들을 해수면 위에 설치하는 것이 바람직하다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.33 no.2
• /
• pp.130-134
• /
• 2020

Metal oxide varistors (MOVs) protect circuits and devices from transient overvoltages in electric power systems. However, a MOV continuously deteriorates owing to manufacturing defects or repetitive protective operations from transient overvoltages. A deteriorated MOV may result in a short circuit or a line-ground accident. Previous studies focused on the analysis of deterioration mechanisms and condition diagnosis techniques for MOVs owing to their recent growth of use. An accelerated deterioration experiment under the same conditions in which a MOV operates is essential. In this study, we designed and fabricated a surge generator that can apply a surge current to a MOV connected to AC mains. The coupling network operates at a low impedance against the surge current from the surge generator and transfers the surge current to the MOV under test. It also acts as a high impedance against AC mains for the AC voltage not to be applied to the surge generator. The decoupling network operates at a high impedance against the surge current and blocks the surge current from AC mains. It also acts as a low impedance against AC mains for the AC voltage to be applied to the MOV under test. The prototype surge generator can apply the 8/20 us up to 15 kA on AC voltages in the approximate range of 110~450 V, and it fully operates on a LabVIEW-based program.

• Ocean Systems Engineering
• /
• v.14 no.1
• /
• pp.17-52
• /
• 2024

In this paper, the authors explore the modeling and control of a point absorber wave energy converter, which is connected to the electric grid via a power converter that is based on a linear permanent magnet synchronous generator (LPMSG). The device utilizes a buoyant mechanism to convert the energy of ocean waves into electrical power, and the LPMSG-based power converter is utilized to change the variable frequency and voltage output from the wave energy converter to a fixed frequency and voltage suitable for the electric grid. The article concentrates on the creation of a predictive control system that regulates the speed, voltage, and current of the LPMSG, and the modeling of the system to simulate its behavior and optimize its design. The predictive model control is created to guarantee maximum energy output and stable grid connection, using Matlab Simulink to validate the proposed strategy, including control side generator and predictive current grid-side converter loops.

• Ocean Systems Engineering
• /
• v.8 no.2
• /
• pp.119-166
• /
• 2018

The assessment of the potential for the design of marine renewable energy systems is reviewed and the current situation for marine renewable energy is promising. The most studied forms of marine renewable energy are ocean wind energy, ocean wave energy and tidal energy. Wind turbine generators include mostly horizontal axis type and vertical axis type. But also more exotic ideas such as a kite design. Wave energy devices consist of designs converting wave oscillations in electric power via a power take off equipment. Such equipment can take multiple forms to be more efficient. Nevertheless, the technology alone cannot be the only step towards marine renewable energy. Many other steps must be overcome: policy, environment, manpower as well as consumption habits. After reviewing the current conditions of marine renewable energy development, the authors analyzed the key factors for developing a strong marine renewable energy industry and pointed out the huge potential of marine renewable energy.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.25 no.11
• /
• pp.1603-1611
• /
• 2021

As IMO environmental regulations are tightened, the need to establish a system that can reduce emissions is increasing, and for this purpose, various power control management systems have been studied and implemented as a new energy management system for ships. In this study, we design a control process through modeling for Bi-Directional Converter (BDC) application with bi-directional power flow to link batteries, which are energy storage devices, to conventional generator power systems, and propose mechanisms for batteries optimized for varying loads. This work models MATLAB/Simulink as a BDC and simulates current control and state of charge (SOC) optimization at the time of charging and discharging batteries according to load scenarios. Through this, the battery, power, and load were interlocked so that the generator operated on board could be operated in the optimal operation range, and power control management was performed to enable the generator to operate in the high fuel efficiency range.