• Journal of KIISE:Computing Practices and Letters
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• v.10 no.5
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• pp.375-384
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• 2004

The Grid is new infrastructure to provide computing environment for grand challenge research by sharing large-scale resources. Currently the Globus becomes a de facto standard middleware to construct Grid and supports core services such as resource management, security, data transfer, information services, and so on. However, it still needs more works and researches to satisfy requirements from various grid applications. A workflow management is becoming a main service as one of the important grid services for complex grid applications. We propose a Meta Scheduling Framework (MSF) in this paper. The MSF provides a XML-based Job Control Markup Language (JCML) for describing information and procedures of grid applications, and a workflow management service for scheduling the job using the JCML and for processing the job effectively.

• Journal of Electrical Engineering and Technology
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• v.8 no.1
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• pp.20-30
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• 2013

An intelligent grid computing architecture is proposed and developed for transient stability constrained total transfer capability evaluation of future smart grid. In the proposed intelligent grid computing architecture, a model of generalized compute nodes with 'able person should do more work' feature is presented and implemented to make full use of each node. A timeout handling strategy called conditional resource preemption is designed to improve the whole system computing performance further. The architecture can intelligently and effectively integrate heterogeneous distributed computing resources around Intranet/Internet and implement the dynamic load balancing. Furthermore, the robustness of the architecture is analyzed and developed as well. The case studies have been carried out on the IEEE New England 39-bus system and a real-sized Chinese power system, and results demonstrate the practicability and effectiveness of the intelligent grid computing architecture.

• 전기의세계
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• v.60 no.11
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• pp.56-63
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• 2011

In the face of global warming and resource depletion, a smart grid has been suggested as one way of contributing to abating the environment problems and increasing energy efficiency. Smart grids utilize renewable energy which has intermittent and irregular output power depending on weather conditions. In order to maintain stability and reliability of the power system, smart grids need to have complementary measures for the possible unstable system conditions. Cogenerating systems such as Combined Heat and Power(CHP) can be one good solution as it has capability of instantly increasing or decreasing output power. Therefore, this paper investigates the connectivity between Combined Heat and Power systems and smart grid technologies. The smart grid national roadmap formulated by South Korea Ministry of Knowledge and Economy and 'IEC Smart Grid Standardization Roadmap' are analyzed to extract related components of the smart grid for the CHP connection. Also, case studies on demonstration projects for smart grids with CHP systems completed or currently being implementing in the world are presented.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.11
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• pp.89-95
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• 2013

In resent years, Offshore Wind Farm (OWF) is being actively developed. Typically, OWF has a better wind resource than onshore one, but also have a very high investment cost and maintenance cost. Furthermore, due to a difficulty of geographical access, OWF can be affected by the failure for a longer time. As the result, OWF has a higher loss cost. Therefore, a reliability evaluation should be performed more carefully at OWF planning stage. In this paper, a methodology for the reliability evaluation on inner grid is suggested. Inner grid connects wind turbines via submarine cables and transfers power to offshore substation. According to location of the faulted cable under layouts of inner grid, the transfer ability of inner grid is influenced. In order to indicate the transfer ability of inner grid, several indices are introduced such as PNDR, EEND and EENDC. To demonstrate the methodology described in this paper, diversity case studies were performed.

• Journal of Information Processing Systems
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• v.7 no.2
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• pp.299-320
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• 2011

The overhead of processing fine-grain tasks on a grid induces the need for batch processing or task group deployment in order to minimise overall application turnaround time. When deciding the granularity of a batch, the processing requirements of each task should be considered as well as the utilisation constraints of the interconnecting network and the designated resources. However, the dynamic nature of a grid requires the batch size to be adaptable to the latest grid status. In this paper, we describe the policies and the specific techniques involved in the batch resizing process. We explain the nuts and bolts of these techniques in order to maximise the resulting benefits of batch processing. We conduct experiments to determine the nature of the policies and techniques in response to a real grid environment. The techniques are further investigated to highlight the important parameters for obtaining the appropriate task granularity for a grid resource.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.5
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• pp.1093-1101
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• 2017

Microgrid as a unit component consisting a smart grid is an isolated system, which has a decentralized power supply system. This paper proposes an electrical isolation of the microgrid from the utiliy grid based on a power conditioning system, and also proposes an operation method maintaining the isolated state efficiently using diverse distributed energy resources such as renewable energy sources and energy storage system. The proposed system minimizes the influence of the grid connection on the internal load though a phase detection and synchrnoization to the utiligy grid and the microgrid can be stable even if the grid is failed.

• KEPCO Journal on Electric Power and Energy
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• v.4 no.1
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• pp.1-7
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• 2018

Objective signs are everywhere that the stationary energy storage market is growing up quickly. The use of distributed resources such as solar photovoltaics and electric vehicles are expanding at a rapid pace, creating technical challenges for the distribution system that will require energy storage and a new generation of software to address. This paper is intended for distribution utility managers and executives and makes the following points: ${\bullet}$ Utility-integrated (as opposed to merely grid-connected) energy storage projects represent a distinct, new wave of industry growth that is just getting underway and is required to manage distributed energy resources moving forward. ${\bullet}$ Utilities and the energy storage industry have important roles to lower risk in adopting this technology - thereby enabling this wave of growth. ${\circ}$ The industry must focus on engineering energy storage for adoption at scale - including the creation and support of software open standards -both to drive down costs and to limit technology and supplier risk for utilities. ${\circ}$ Utilities need to take a program-based, rather than a project- based, approach to this resource to best balance cost and risk as they procure and implement energy storage. By working together to drive down costs and manage risk, utilities and their suppliers can lay the energy storage foundation for a new, more digital distributed electricity system.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.4
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• pp.569-575
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• 2016

In this paper, we propose a method to develop a static equivalent model of an inverter-based distributed energy resource (DER), where the model is used for a steady-state fault analysis of a power grid. First, we introduce the characteristics of an inverter-based DER as well as its general configuration. Then, we derive the equivalent model of the DER on the basis of the characteristics. Last, the performance of the proposed method is proven by the results of computer simulations.

• International Journal of Computer Science & Network Security
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• v.22 no.5
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• pp.1-4
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• 2022

The growth in global population and industrialization has led to an increasing demand for electricity. Accordingly, the electricity providers need to increase the electricity generation. Due to the economical and environmental concerns associated with the generation of electricity from fossil fuels. Alternative power recourses that can potentially mitigate the economical and environmental are of interest. Renewable energy resources are promising recourses that can participate in producing power. Among renewable power resources, solar energy is an abundant resource and is currently a field of research interest. Photovoltaic solar power is a promising renewable energy resource. The power output of PV systems is mainly affected by the solar irradiation and ambient temperature. this paper investigates the utilization of machine learning unsupervised neural network techniques that potentially improves the reliability of PV solar power systems during integration into the electrical grid.

• International Journal of Computer Science & Network Security
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• v.22 no.5
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• pp.67-72
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• 2022

There has been a significant growth in global population and industrialization, as a consequence demand for electricity is increasing rapidly and the power systems need to increase the electricity generation. Currently, most of generated electricity is generated from fossil fuels. However, there are many financial and environmental concerns associated with the generation of electricity from such resource. Photovoltaic )PV) solar as a renewable resource is promising. The power output of PV systems is mainly affected by the solar irradiation and ambient temperature. This paper attempts at reducing the burden and improving the accuracy of the extensive simulations related to integrating PV systems into the electrical grid.