• The Journal of the Korea institute of electronic communication sciences
• /
• v.19 no.1
• /
• pp.65-76
• /
• 2024

With the recent activation of the offshore wind power industry, there has been a development of power plants with a scale exceeding 400MW, comparable to traditional thermal power plants. Renewable energy, characterized by intermittency depending on the energy source, is a prominent feature of modern renewable power generation facilities, which are structured based on controllable inverter technology. As the integration of renewable energy sources into the grid expands, the grid codes for power system connection are progressively becoming more defined, leading to active discussions and evaluations in this area. In this paper, we propose a method for selecting optimal reactive power compensation capacity when multiple offshore wind farms are integrated and connected through a shared interconnection facility to comply with grid codes. Based on the requirements of the grid code, we analyze the reactive power compensation and excessive stability of the 400MW wind power generation site under development in the southwest sea of Jeonbuk. This analysis involves constructing a generation site database using PSS/E (Power System Simulation for Engineering), incorporating turbine layouts and cable data. The study calculates reactive power due to charging current in internal and external network cables and determines the reactive power compensation capacity at the interconnection point. Additionally, static and dynamic stability assessments are conducted by integrating with the power system database.

• 한국신재생에너지학회:학술대회논문집
• /
• 2011.11a
• /
• pp.43.1-43.1
• /
• 2011

The detail simulation modeling of fully-fed induction generator is investigated through PC based MATLAB/Simulink environment. Generator's stator currents are controlled by indirect vector control method. In this method, generator side converter controls the maximum excitation (air gap flux) by stator d-axis current and controls generator torque by stator q-axis current. Induction generator speed is controlled by tip speed ratio (TSR) upon the wind speed variations in order to generate the maximum output power. The generator torque model is specified as a 3-blade wind turbine with rating, then, the model is simulated under normal operating condition and three different fault conditions. The matlab model designed for fully-fed induction generator based wind farm provides good performance under normal and grid fault conditions. It provides good results for different pwm techniques and fault conditions except the single-phase line to ground fault, which should be verified with real time data from wind farms.

• Proceedings of the KIPE Conference
• /
• 2013.11a
• /
• pp.235-236
• /
• 2013

전력 시스템의 변화 및 전력 전자 소자의 발전으로 인하여 HVDC 시스템에 대한 관심이 높아지고 있다. 또한 기존의 Point-to-Point 형태의 HVDC 시스템에서 진보하여, 멀티 터미널 형태 그리고 풍력단지와 연계된 다양한 Topology가 계획 중이거나 실제도 구동되고 있다. 따라서 이러한 추세에 맞추어 풍력단지와 연계된 멀티터미널 시스템을 구현하였다. 본 시스템은 세 곳의 AC 계통 시스템과 한 곳의 풍력단지로 이루어져 있으며, 이는 전압형 컨버터를 통하여 DC 계통을 구성하였다. 풍력발전의 변동 및 Master 컨버터의 탈락 시험 또한 진행하였다.

• Proceedings of the KIEE Conference
• /
• 2015.07a
• /
• pp.623-624
• /
• 2015

최근 산업의 발달로 전력소비량이 증가하면서 전력계통 주파수 안정화 및 전력평준화에 대한 대안으로 ESS에 대한 관심이 높아지고 있다. 이에 대해 출력변동이 심한 풍력발전에 배터리를 연계하여 운영하는 방법에 대한 연구가 활발히 진행되고 있다. 그러나 현재 국내에서는 ESS 연계 시 높은 초기자본비용과 ESS 운영방법에 대한 문제로 아직까지 활성화되지 못하고 있다. 따라서 본 논문에서는 ESS 연계 풍력발전단의 전력판매수익을 극대화하기 위한 운영기법에 대한 연구를 진행하였다.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.404-405
• /
• 2011

In this paper, we present basic modeling of Juju power system using PSCAD/EMTDC. In detail, models of bipolar HVDC system, power transmission line, basic thermal power plant, load, and wind farm have been developed for Jeju power system. For evaluating basic dynamic behavior, we tested the system with a simple scenario and the test result showed acceptable response.

• Proceedings of the KIEE Conference
• /
• 2003.11a
• /
• pp.345-347
• /
• 2003

본 논문에서는 분산전원이 기존의 배전계통상에 도입되는 경우에 대하여 전압변동해석을 수행하기 위하여, 풍력발전단지가 도입된 제주 성산 변전소를 선정하여 MATLAB 프로그램을 이용하여 시뮬레이션을 수행하고 전압변동상황을 예측, 이에 따른 문제점과 그에 대한 대책을 제시하도록 할 것이다.

• Journal of Navigation and Port Research
• /
• v.37 no.6
• /
• pp.655-662
• /
• 2013

Recently, by the problems owing to utilization of fossil fuel, various green energies receive attention. Wind, the impetus for the wind power generation as one of the green energies, is observed higher quality value in the offshore than onshore. Also, the development of offshore wind turbines is in the spotlight as alternative to solve the problems of onshore wind farm such as securing sites, noise, and electromagnetic waves, and to get efficient wind energy. Therefore, the many researches on offshore wind energy have been carried out. As wind towers are advanced to ocean, offshore wind towers have been enlarged. Thus, stability is required to endure wind force and wave force. In this study, the external forces act on the foundation in multi-layered are calculated by p-y relation.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2012.04a
• /
• pp.993-996
• /
• 2012

전 세계적으로 신재생에너지에 대한 관심이 고조되고 있는 가운데, 국내에서도 대규모 해상 풍력발전단지 개발을 진행중에 있다. 현재 풍력발전단지 운영 기술인 SCADA 시스템의 국내 기술 수준은 매우 낮은 수준으로 현장 적용 가능한 SCADA 시스템 개발이 시급한 실정이다. 따라서 본 논문에서는 대규모 해상 풍력발전단지 SCADA 시스템 개발을 위해서 필요한 고려 사항을 분석하였다.

• Korean Chemical Engineering Research
• /
• v.61 no.1
• /
• pp.142-154
• /
• 2023

As the importance of the environment has been recognized worldwide, the need to calculate and reduce carbon emissions has been drawing an increasing attention throughout various industrial sections. Thereby the discipline of LCA (Life Cycle Assessment) involving raw material preparation, production processes, transportation and installation has been established. There is a clear research gap between the need and the practice for Korean Case of renewable energy industry, particularly wind power. To bridge the gap, this study conducted LCA research on wind power generation in the Korean area of Yeongdeok, an example of a domestic onshor wind power complex using SimaPro, which is the most widely used LCA system. As a result of the study, the energy recovery period (EPT) of one wind turbine is about 10 months, and the GHG emitted to generate power of 1 kwh is 15 g CO₂/kWh, which is competitive compared to other energy sources. In the environmental impact assessment by component, the results showed that the tower of wind turbines had the greatest impact on various environmental impact sectors. The experience gained in this study can be further used in strengthening the introduction of renewable energy and reducing the carbon emission in line with reducing climate change.

• Journal of Electrical Engineering and Technology
• /
• v.12 no.2
• /
• pp.689-700
• /
• 2017

This paper presents an effective approach for wind turbine (WT) condition assessment based on the data collected from wind farm supervisory control and data acquisition (SCADA) system. Three types of assessment indices are determined based on the monitoring parameters obtained from the SCADA system. Neural Networks (NNs) are used to establish prediction models for the assessment indices that are dependent on environmental conditions such as ambient temperature and wind speed. An abnormal level index (ALI) is defined to quantify the abnormal level of the proposed indices. Prediction errors of the prediction models follow a normal distribution. Thus, the ALIs can be calculated based on the probability density function of normal distribution. For other assessment indices, the ALIs are calculated by the nonparametric estimation based cumulative probability density function. A Back-Propagation NN (BPNN) algorithm is used for the overall WT condition assessment. The inputs to the BPNN are the ALIs of the proposed indices. The network structure and the number of nodes in the hidden layer are carefully chosen when the BPNN model is being trained. The condition assessment method has been used for real 1.5 MW WTs with doubly fed induction generators. Results show that the proposed assessment method could effectively predict the change of operating conditions prior to fault occurrences and provide early alarming of the developing faults of WTs.