• 한국인터넷방송통신학회논문지
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• 제19권3호
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• pp.179-184
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• 2019

전기가 부족한 개발도상국 같은 많은 나라에서는 Off Grid 형태의 소형풍력발전이 전력공급 문제를 해결하기 위한 효율적인 핵심 솔루션이다. 몇몇 국가에서는 전력계통의 확장과 전기가 부족한 지역의 감소로 소규모 풍력을 도시의 도로 조명, 모바일 통신 기지국, 양식업 및 해수 담수 등의 분야에 이용하기도 한다. 이런 변화에 따라 소형 풍력 산업 규모는 대규모 풍력보다 큰 잠재력이 기대되고 있다. 소형 풍력발전의 경우 발전기는 가변 속도로 제어되는 특성이 있으며 발전기에서 발생하는 전압 및 전류에는 많은 고조파 성분을 가지고 있다. 이를 해결하기 위해서 본 논문에서는 소형 풍력발전시스템의 직류전원 적용을 위한 운전제어 및 AC/DC 변환 통합장치를 제안하며 기존 AC to DC 컨버터는 단일 스위치를 갖는 3상 승압형 방식의 컨버터로서 인덕터 전류가 불연속모드로 제어되며, 입력전류의 고조파를 제거하여 단위역률을 갖는 특성을 갖는다. 제안된 컨버터는 입력단에 LCL 필터 및 3상 정류 승압형 컨버터, 계통연계를 위한 단상 풀브릿지 형태로 구성되어 있으며 에너지저장시스템(ESS) 기능이 부가된 제어 시스템으로 풍력발전을 이동 평준화 방식에 의해 급변하는 전력에 대해 계통 안정화를 추구할 수 있다.

• 전기학회논문지P
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• 제51권4호
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• pp.169-174
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• 2002

The developments of the solar and the wind power energy are neccessary since the future alternative energies that have no pollution and no limitation are restricted. Currently power generation system of existing problems, combined generation system of photovoltaic(400W) and wind power generation system(400W) was suggested. It combines wind power and solar energy to have the supporting effect from each other. However, weather condition, power compensation device that uses elastic energy of spiral spring to combined generation system was also added for the present study. In an experiment, when output of system gets lower than 12V(charging voltage), power was continuously supplied to load through the inverter by charging energy obtained from generating rotary energy of spiral spring operates in small scale generator.

• Wind and Structures
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• 제29권6호
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• pp.405-416
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• 2019

Aerodynamic characteristic of a small scale wind turbine under the influence of an incoming uniform wind field is studied using k-ω Shear Stress Transport turbulence model. Firstly, the lift and drag characteristics of the blade section consisting of S826 airfoil is studied using 2D simulations at a Reynolds number of 1×10⁵. After that, the full turbine including the rotational effects of the blade is simulated using Multiple Reference Frames (MRF) and Sliding Mesh Interface (SMI) numerical techniques. The differences between the two techniques are quantified. It is then followed by a detailed comparison of the turbine's power/thrust output and the associated wake development at three tip speeds ratios (λ = 3, 6, 10). The phenomenon of blockage effect and spatial features of the flow are explained and linked to the turbines power output. Validation of wake profiles patterns at multiple locations downstream is also performed at each λ. The present work aims to evaluate the potential of the numerical methods in reproducing wind tunnel experimental results such that the method can be applied to full-scale turbines operating under realistic conditions in which observation data is scarce or lacking.

• 한국통신학회논문지
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• 제40권9호
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• pp.1808-1818
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• 2015

최근 신재생 에너지 중 각광을 받고 있는 풍력 발전의 경우 경제성 및 효율성을 높이기 위하여 대부분의 풍력 발전단지들이 해상에 조성된다. 그러나 풍력단지 관리자가 해상에 설치된 풍력발전기에 접근하기 위해서는 헬기 또는 보트를 이용해야하며 많은 비용과 시간을 필요로 한다. 이러한 유지 및 관리 비용을 감소시키기 위한 하나의 대안으로써 풍력발전기의 원격 모니터링 및 제어 기술이 요구된다. 본 논문에서는 풍력발전기의 상태 정보 계측 및 원격 제어 기능을 제공하는 무선 센서 네트워크 기반의 풍력발전기 모니터링 및 제어 시스템을 구현한다. 이를 위해 다수의 센서를 풍력발전기에 설치하여 실시간으로 상태를 계측할 수 있도록 하고 제어 장치를 통해 원격 제어가 가능하도록 한다. 풍력발전기의 센서 장치 및 제어 장치는 무선 센서 네트워크를 통해 제어 센터와 계측 데이터 및 제어 데이터를 주고받도록 한다. 제어 센터에서는 GUI 기반의 모니터링과 제어 기능을 제공하는 중앙 집중형 모니터링 프로그램을 통해 풍력발전기를 관리한다. 또한 제어 센터 이외의 지역에서 원격으로 풍력발전기 모니터링이 가능하도록 스마트 단말기 기반의 웹 프로그램을 구현한다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2003년도 춘계전력전자학술대회 논문집(2)
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• pp.933-937
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• 2003

The development of the solar and the wind power energy are necessary since the future alternative energies that have no pollution and no limitation are restricted. Currently power generation system of MW scale has been developed, but it still has a few faults with the weather condition. In order to solve these existing problems, combined generation system of photovoltaic(400w) and wind power generation system(400w) was suggested. It combines wind power and solar energy to have the supporting effect from each other However, since even combined generation system cannot always generate stable output with ever-changing weather condition, power compensation device that uses elastic energy of spiral spring to combined generation system was also added for the present study. In an experiment, when output of system gets lower than 12V(charging voltage), power was continuously supplied to load through the inverter by charging energy obtained from generating rotary energy of spiral spring operates in small scale generator

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.133-138
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• 2002

The developments of the solar and the wind power energy are necessary since the future alternative energies that have no pollution and no limitation are restricted. Currently power generation system of MW scale has been developed, but it still has a few faults with the weather condition. In order to solve these existing problems, combined generation system of photovoltaic(400W) and wind power generation system(400W) was suggested. It combines wind power and solar energy to have the supporting effect from each other. However, since even combined generation system cannot always generate stable output with ever-changing weather condition, power compensation device that uses elastic energy of spiral spring to combined generation system was also added for the present study. In an experiment, when output of system gets lower than 12V(charging voltage), power was continuously supplied to load through the inverter by charging energy obtained from generating rotary energy of spiral spring operates in small scale generator.

• Journal of Advanced Research in Ocean Engineering
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• 제2권4호
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• pp.179-191
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• 2016

As the demand for renewable energy has increased following the worldwide agreement to act against global climate change and disaster, large-scale floating offshore wind systems have become a more viable solution. However, the cost of the whole system is still too high for practical realization. To make the cost of a floating wind system be more economical, a new concept of tension leg platform (TLP) type ocean floating wind system has been developed. To verify the performance of a 5-MW TLP type ocean floating wind power system designed by the Korea Advanced Institute of Science and Technology, the FAST simulation developed by the National Renewable Energy Laboratory is used. Further, 1/50 scale model tests have been carried out in the ocean engineering tank of the Research Institute of Medium and Small Shipbuilding, Korea. This paper compares the simulation and ocean engineering tank test results on motion prediction and tension assessment of the TLP anchor.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.455-458
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• 2001

This paper presents an axial flux permanent magnet synchronous generator with a high power-to-weight ratio, dedicated for small-scale gearless wind power generation plants. For this purpose, a specific design is necessary to meet the imposed requirements. In this paper the design technique for the specifications is presented. The aim of the paper is also to discuss some of the first obtained test results and the involved demagnetizing problem (i.e. short-circuit).

• Journal of Power Electronics
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• 제12권2호
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• pp.326-332
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• 2012

This paper proposes a simple active damping algorithm for small-scale wind power systems with an LCL filter. Compared to an L filter or an LC filter, an LCL filter can decrease the harmonics induced by low switching frequencies and produce a satisfactory grid-side current using a comparatively low inductance. Additional active damping of the filter resonance is necessary when an LCL filter is used. This paper introduces an active damping method using a Discrete Fourier Transform (DFT) filter to improve performance without additional sensors or complexity. Experimental results are shown to verify the validity of the proposed algorithm as an active damping method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.830_831
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• 2009

Wind power system attracts most interest because of high-energy efficiency with environment-friendly. Small scale wind power applications requires a cost effective and mechanically simple generator in order to be a reliable energy source. The use of direct driven generators, instead of geared machines, reduces the number of drive components, which offers the opportunity to reduce costs and increases system reliability and efficiency. This paper presents the development of a coreless axial-flux permanent magnet(AFPM) generator for a urban wind power system. It is analyzed by electromagnetic simulation program Maxwell 3D