• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• 제4B권3호
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• pp.146-152
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• 2004

Cost effective simulation schemes for Wind Power Generation Systems (WPGS) considering wind turbine types, generators and load capacities have been strongly investigated by researchers. As an alternative, a true weather condition based simulation method using a real-time digital simulator (RTDS) is experimented in this paper for the online real-time simulation of the WPGS. A stand-alone WPGS is, especially, simulated using the Simulation method for WPGS using Real Weather conditions (SWRW) in this work. The characteristic equation of a wind turbine is implemented in the RTDS and a RTDS model component that can be used to represent any type of wind turbine in the simulations is also established. The actual data related to weather conditions are interfaced directly to the RTDS for the purpose of online real-time simulation of the stand-alone WPGS. The outcomes of the simulation demonstrate the effectiveness of the proposed simulation scheme. The results also signify that the cost effective verification of efficiency and stability for the WPGS is possible by the proposed real-time simulation method.

• 전력전자학회논문지
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• 제9권1호
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• pp.73-80
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• 2004

본 논문에서는 농형유도발전기를 이용한 독립형 풍력발전시스템의 최대전력 추종제어기법을 제안한다. 농형 유도발전기는 벡터제어 방식으로 동작되는데 d-축 전류에 의해 여자가 제어되고 q-측 전류에 토크가 제어된다. 이 토크제어에 의해 발전기는 풍속의 변화에 따라 최대전력을 발생하도록 가변속 제어된다. 발전된 전력은 ac/dc PWM 컨버터에 의해 직류 출력단 배터리뱅크로 충전된다. 제안된 기법은 M-G세트로 구성된 터빈시뮬레이터를 이용하여 실험적으로 검증된다.

• Journal of Advanced Marine Engineering and Technology
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• 제32권8호
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• pp.1123-1128
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• 2008

Marine facilities like buoy, lighthouse are operated with stand alone power supply system. This power system can consist of a stand-alone type power system such as PV(Photovoltaic) system, wave system or hybrid system which is not cooperated with a commercial power system. Generally, PV power system for marine facilities can not supply a sufficient power to buoy, because it is so influenced from weather condition. For solving this problem the hybrid power system with PV and wave is studied on a various area, that is why a hybrid power system is requires to overcome these problems. This paper will describe a generation characteristic of WEC(Wave Energy Converter) for buoy, and an AFS(Anti-Fouling System) influence on WEC.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.338-340
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• 2003

This paper proposes a stand-alone adjustable speed wind Power generation system using a cage-type induction generator. Indirect vector control is used, where the q-axis current controls the generator speed and the d-axis current controls the excitation level. The generator speed is adjusted according to the wind speed so as to produce the maximum output power. The generated power is charged in the battery bank through ac/dc PWM converter. The proposed scheme has been verified by the experimental results.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.2221-2225
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• 2005

Various types of fieldbus are used in factories in order to achieve the communication between the parts of process. But the protocol of the fieldbus doesn't have the standardized unique protocol. Thus, it is hard to exchange information each other with real time base when the different type protocols are adopted in the same network. In this paper, we implement two types of gateway for CAN and Profibus-DP: PC-based gateway and stand-alone gateway using the 80186 core based Dstni-LX network processor. The performance of proposed PC-based and stand-alone gateway is verified experimentally.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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• pp.972-977
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• 1998

This paper deals with stand-alone Photovoltaic system(SPVS) with charge and discharge controller. Main power source of SPVS are generally solar cell and battery. Therefore SPVS can be classified into variable types in accordance with connection method between battery and solar cell array. Mainly used one of them is direct connection type which has advantages such as simple structure and simple controller. However most big drawback of this system is energy loss by voltage disharmony between solar cell array and battery. Therefore SPVS with charge and discharge controller which can operate solar cell array at maximum power point is designed and experimented with a laboratory prototype.

• Journal of Korean Neurosurgical Society
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• 제47권5호
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• pp.352-357
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• 2010

Objective : This retrospective study was performed to evaluate the clinical and radiological results of anterior lumbar interbody fusion (ALIF) using two different stand-alone cages in the treatment of lumbar intervertebral foraminal stenosis (IFS). Methods : A total of 28 patients who underwent ALIF at L5-S1 using stand-alone cage were studied [Stabilis$^{(R)}$ (Stryker, Kalamazoo, MI, USA); 13, SynFix-LR$^{(R)}$ (Synthes Bettlach, Switzerland); 15]. Mean follow-up period was 27.3 ${\pm}$ 4.9 months. Visual analogue pain scale (VAS) and Oswestry disability index (ODI) were assessed. Radiologically, the change of disc height, intervertebral foraminal (IVF) height and width at the operated segment were measured, and fusion status was defined. Results : Final mean VAS (back and leg) and ODI scores were significantly decreased from preoperative values (5.6 ${\pm}$ 2.3 ${\rightarrow}$ 2.3 ${\pm}$ 2.2, 6.3 ${\pm}$ 3.2 ${\rightarrow}$1.6 ${\pm}$ 1.6, and 53.7 ${\pm}$ 18.6 ${\rightarrow}$ 28.3 ${\pm}$ 13.1, respectively), which were not different between the two devices groups. In Stabilis$^{(R)}$ group, postoperative immediately increased disc and IVF heights (10.09 ${\pm}$ 4.15 mm ${\rightarrow}$ 14.99 ${\pm}$ 1.73 mm, 13.00 ${\pm}$ 2.44 mm ${\rightarrow}$ 16.28 ${\pm}$ 2.23 mm, respectively) were gradually decreased, and finally returned to preoperative value (11.29 ${\pm}$ 1.67 mm, 13.59 ${\pm}$ 2.01 mm, respectively). In SynFix-LR$^{(R)}$ group, immediately increased disc and IVF heights (9.60 ${\pm}$ 2.82 mm ${\rightarrow}$ 15.61 ${\pm}$ 0.62 mm, 14.01 ${\pm}$ 2.53 mm ${\rightarrow}$ 21.27 ${\pm}$ 1.93 mm, respectively) were maintained until the last follow up (13.72 ${\pm}$ 1.21 mm, 17.87 ${\pm}$ 2.02 mm, respectively). The changes of IVF width of each group was minimal pre- and postoperatively. Solid arthrodesis was observed in 11 patients in Stabilis group (11/13, 84.6%) and 13 in SynFix-LR$^{(R)}$ group (13/15, 86.7%). Conclusion : ALIF using stand-alone cage could assure good clinical results in the treatment of symptomatic lumbar IFS in the mid-term follow up. A degree of subsidence at the operated segment was different depending on the device type, which was higher in Stabilis$^{(R)}$ group.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 B
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• pp.1382-1384
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• 2002

The flooded type battery is used for solar lighting system. Because the characteristic of flooded type battery is the short life time, the maintenance cost is high. So the using flooded type battery in this system is inappropriate. The valve regulated lead acid batter.(VRLA) is the maintenance free and cycle service purpose. This paper presents the development of control system and monitoring system to applied VRLA battery for maintenance free and long life time in system.

• 한국항해항만학회지
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• 제35권9호
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• pp.749-753
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• 2011

A leisure ship has a stand-alone type power system, and a generator is in use on this condition. But the generator cannot be operated in condition of leisure activity, ocean measurement and etc, because of environment and noise. Recently, renewable energy system is connected with power system of the leisure-ship for saving energy. The renewable energy system can not supply the stable power to leisure-ship because power generation changes according to weather condition. And most of the leisure ship is operated without methodical power management system. This study's purpose is to develop SPMS(Smart Power Management System) algorithm using the renewable energy (photovoltaic, wind power and etc.). The proposed algorithm is able to supply stable the power according to operation mode. Furthermore, the SPMS manages electric load (sailing and communication equipment, TV, fan, etc.) and reduces operating times of the generator. In this paper, the proposed algorithm is realized and executed by using LabVIEW. As a result, the hour for operating the generator is minimized.

• 전력전자학회논문지
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• 제4권1호
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• pp.57-65
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• 1999

본 논문은 충방전 제어기를 사용한 독립형 태양광 발전시스템을 다루고 있다. 독립형 태양광 발전시스템의 주전원은 일반적으로 태양전지와 배터리이다. 그러므로 독립형 태양광 발전시스템은 배터리와 태양전지와의 결선에 따라서 다양한 형태로 구분할 수 있다. 그중 주로 사용되는 결선은 태양전지와 배터리를 직접 연결하는 것으로 단순하고 간결한 구조를 갖는 이점이 있다. 그러나 그러한 시스템은 배터리와 솔라셀 사이의 전압불균형으로 인한 손실을 갖는다. 그러므로 태양전지를 최대전력점으로 운전할 수 있는 충방전 제어기를 갖는 독립형 태양광 발전시스템을 제안하여 순시치제어기로 설계하였다. 시스템의 동작특성을 실험실의 초기 시작품으로 검증되었다.