• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.606-607
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• 2007

This paper is about optimal flywheel capacity estimation for Ullueng-do power system. The power system of Ullueng-do has some differences with other island power system in Korea. It includes wind generator, hydro-generators as well as diesel generators. There are some problems on 600kW wind generator. Because of frequent drop of wind generator, the Ulleung-do power system have been threatened on frequency. The power frequency is 60Hz, and it should be between 59.9 and 60.1Hz. However, since the electrical inertia is small and the weight of wind generation is relatively high, generator drop of wind generation might make the power frequency out of boundary. In this paper, the flywheel energy storage system is assumed to be installed on Ulleung-do power system. Then, the maximum wind generation capacity and the optimal superconducting flywheel energy storage system capacity is estimated by the transient stability simulations.

• 신재생에너지
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• 제8권3호
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• pp.14-22
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• 2012

Performance of photovoltaic (PV) generator systems relies on its operating conditions. Maximum power extracted from PV generators depends strongly on solar irradiation, load impedance, and ambient temperature. A most maximum power point tracking (MPPT) algorithm is based on a perturb and observe method and an incremental conductance method. It is well known the latter is better in terms of dynamics and tracking characteristics under condition of rapidly changing solar irradiation. However, in case of digital implementation, the latter has some error for determining a maximum power point. This paper presents a PID based MPPT algorithm for such PV systems. We use neural network technique for determining PID parameters by online learning approach. And we construct a boost converter to regulate the output voltage from PV generator system. Computer simulation is carried out to evaluate the proposed MPPT method and we accomplish comparative study with a perturb and observe based MPPT method to prove its superiority.

• 풍력에너지저널
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• 제10권4호
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• pp.20-27
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• 2019

High-speed shaft coupling in a wind power system transmits power and absorbs variations in length and spindle dislocation between the gearbox and generator. Furthermore, the coupling has an insulation function that prevents electrical corrosion caused by the flow of the generator's current into the gearbox and prevents overload resulting from sudden power failure from being transferred to the gearbox. Its design, functions, and part verification are described in the IEC61400 and GL Guidelines, which specify that the part must have a durability life of 20 years or longer under distance variation and axial misalignment between the gearbox and the generator. This study presents the design of a high-speed coupling through composite stiffness calculation, structural analysis, and comparative analysis of test and theory to identify the characteristics of high-speed coupling for a large-capacity 6 MW wind power generator. A prototype was fabricated by optimizing the manufacturing process for each part based on the design, and the reliability of the fabricated prototype was verified by evaluating the performance of the target quantitative evaluation items.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2003년도 추계 학술발표회 논문집
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• pp.337-342
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• 2003

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2001년도 추계 학술발표회 논문집
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• pp.317-324
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• 2001

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2004년도 춘계 학술발표회 논문집
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• pp.377-382
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• 2004

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2002년도 춘계공동학술발표회요약집
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• pp.206.2-206
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• 2002

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2005년도 춘계학술발표회
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• pp.589-590
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• 2005

• Nuclear Engineering and Technology
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• 제39권2호
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• pp.103-110
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• 2007

The High Temperature Gas-cooled Reactor (HTGR) possesses inherent safety features and is recognized as a representative advanced nuclear system for the future. Based on the success of the HTR-10, the long-time operation test and safety demonstration tests were carried out. The long-time operation test verifies that the operation procedure and control method are appropriate for the HTR-10 and the safety demonstration test shows that the HTR-10 possesses inherent safety features with a great margin. Meanwhile, two new projects have been recently launched to further develop HTGR technology. One is a prototype modular plant, denoted as HTR-PM, to demonstrate the commercial capability of the HTGR power plant. The HTR-PM is designed as $2{\times}250$ MWt, pebble bed core with a steam turbine generator that serves as an energy conversion system. The other is a gas turbine generator system coupled with the HTR-10, denoted as HTR-10GT, built to demonstrate the feasibility of the HTGR gas turbine technology. The gas turbine generator system is designed in a single shaft configuration supported by active magnetic bearings (AMB). The HTR-10GT project is now in the stage of engineering design and component fabrication. R&D on the helium turbocompressor, a key component, and the key technology of AMB are in progress.

• Journal of international Conference on Electrical Machines and Systems
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• 제1권4호
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• pp.464-471
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• 2012

Self-excited induction generators (SEIG) are gaining importance as compared to conventional generators due to their capability toconvert wind energy into electrical energy for a wide range of variation in operating speed. The performance of such a generator depends upon the load, rotor speed and excitation capacitance. Therefore, depending upon the operating conditions, the output voltage and frequency of this machine goes on changing and this imposes a restriction on its usage. In order to maintain constant voltage and frequency, it need controllers, which make the circuit complicated and also increases the overall cost of power generation. This paper presents a simple controller to regulate the output voltage and frequency of SEIG for variation in its operating conditions due to any change in load, rotor speed and excitation capacitance (R, N, C) and their combination. The controller presented is simple in design, user friendly and is also less expensive, as the elements used in the controller are only resistors, inductors and capacitors. A block of SEIG for steady state operation is also modeled and presented in this paper. SEIG, Controller and other components are modeled and simulated using Matlab/Simulink.