• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 A
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• pp.527-529
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• 2001

Interfaces are the point of interconnection between distributed generation and the energy infrastructure. These interfaces are generally physical but can include a market dimension as well. While there are issues surrounding various interfaces, the most important issues in the short term are on the electrical interface. Much of the discussion and debate surrounding distributed generation interconnection has centered on technical issues. However, there are two elements of Interconnection that merit equal consideration-process and contractual issues. The solution of distributed generation Interconnection issues depends on whether existing requirements can be modified to make them more efficient, transparent, and standardized while maintaining the grid's reliability and safety. In this paper, two main courses, standardization and third party participation, are suggested for the resolution of these issues.

• Journal of Electrical Engineering and Technology
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• 제8권2호
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• pp.223-229
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• 2013

Restructuring and recent developments in the power system and problems arising from construction and maintenance of large power plants, increasing amount of interest in distributed generation (DG) source. Distributed generation units due to specifications, technology and location network connectivity can improve system and load point reliability indices. In this paper, the allocation and sizing of DG in distribution networks are determined using optimization. The objective function of the proposed method is to improve customer-based reliability indices at lowest cost. The placement and size of DGs are optimized using a Genetic Algorithm (GA). To evaluate the proposed algorithm, 34-bus IEEE test system, is used. The results illustrate efficiency of the proposed method.

• Journal of Electrical Engineering and Technology
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• 제2권1호
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• pp.68-80
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• 2007

This paper covers switched reluctance generator (SRG) and its comparison with induction and synchronous machines for distributed generation. The SRG is simple in design, robust in construction, and fault tolerant in operation; it can also withstand very high temperatures. However, the performance and cost of the SRG power electronics driver are highly affected by the topology and design of the converter. IGBT and MOSFET based converters are not suitable for very high power applications. This paper presents thyristor-based resonant converters which are superior candidates for very high power applications. Operations of the converters are analyzed and their characteristics and dynamics are determined in terms of the system parameters. The resonant converters are capable of handling high currents and voltages; these converters are highly efficient and reliable as well. Therefore, they are suitable for high power applications in the range of 1MW or larger for distributed generation.

• Journal of Electrical Engineering and Technology
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• 제3권2호
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• pp.143-151
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• 2008

This paper presents the operation of Fuel Cell Distributed Generation(FCDG) systems in distribution systems. Hence, modeling, controller design, and simulation study of a Solid Oxide Fuel Cell(SOFC) distributed generation(DG) system are investigated. The physical model of the fuel cell stack and dynamic models of power conditioning units are described. Then, suitable control architecture based on fuzzy logic and the neural network for the overall system is presented in order to activate power control and power quality improvement. A MATLAB/Simulink simulation model is developed for the SOFC DG system by combining the individual component models and the controllers designed for the power conditioning units. Simulation results are given to show the overall system performance including active power control and voltage regulation capability of the distribution system.

• 대한인간공학회지
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• 제30권5호
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• pp.683-688
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• 2011

Objective: The aim of this study is to develop a distributed representative human model(DRHM) generation and analysis system. Background: DRHMs are used for a product with multiple-size categories such as clothing and shoes. It is not easy for a product designer to explore an optimal sizing system by applying various distributed methods because of their complexity and time demand. Method: Studies related to DRHM generation were reviewed and the RHM generation interfaces of three digital human model simulation systems(Jack$^{(R)}$, RAMSIS$^{(R)}$, and CATIA Human$^{(R)}$) were reviewed. Results: DRHM generation steps are implemented by providing sophisticated interfaces which offer various statistical techniques and visualization methods with ease. Conclusion: The DRHM system can analyze the multivariate accommodation percentage of a sizing system, provide body sizes of generated DRHMs, and visualize generated grids and DRHMs. Application: The DRHM generation and analysis system can be of great use to determine an optimal sizing system for a multiple-size product by comparing various sizing system candidates.

• 대한전기학회논문지:전력기술부문A
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• 제54권11호
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• pp.518-524
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• 2005

This paper presents an analytical method for the reliability evaluation of distribution system, including the distributed generations. Unlike the large sized generations of transmission system, the distributed generations have complexities in analyzing and determining the operation. In the process of evaluate reliability, it can be shown that the analytical method is simpler than the Monte-Carlo simulation and the method using Load Duration Curve model is more accurate than that using peak load model. The modeling of distributed generation to analysis distribution system reliability using LDC is proposed in this Paper, and is compared with the MCS method as a result of case studies.

• 조명전기설비학회논문지
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• 제23권12호
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• pp.210-216
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• 2009

마이크로그리드는 전력시스템의 계획 및 실시간 운영에 있어서 매우 큰 영향을 미치며 중요한 역할을 할 것으로 판단된다. 따라서 본 연구에서는 빌딩의 마이크로그이드의 중요한 마이크로소오스인 마이크로터빈 발전시스템의 Matlab/Simulink 모델과 전압-주파수제어기를 개발하였다. 또한 부하에 독립적으로 전원을 공급하기 위한 전력시스템을 구성, 모의를 통하여 MTG시스템의 특성을 분석하였다.

• Journal of Power Electronics
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• 제11권3호
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• pp.350-359
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• 2011

This paper describes the operational analysis results of a DC micro-grid using a detailed model of distributed generation. A detailed model of wind power generation, photo-voltaic generation and fuel cell generation was implemented with an userdefined model created with PSCAD/EMTDC software and coded in C-language. The operational analysis was carried out using PSCAD/EMTDC software, in which the power circuit is implemented by a built-in model and the controller is modeled by an user-defined model that is also coded in C-language. Various simulation results confirm that a DC micro-grid can operate without any problems in both the grid-tied mode and in the islanded mode. The operational analysis results confirm that the DC micro-grid makes it feasible to provide power to the load stably. It can also be utilized to develop an actual system design.

• 전기학회논문지
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• 제58권7호
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• pp.1304-1312
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• 2009

The purpose of this study is to build promotive measures and to develop alternative policies of DG(Distributed Generation) by finding and analysing effects of four business environment factors related to DEPB(District Electricity Power Business) on boosting DG. In this study, four business environment factors, which are the electric power industry restructuring, electricity tariff and pricing structure, regulations for DEPB, and conflicts of stake-holding groups, are considered as independent variables. And promotion factors of DG including small CHP(Combined Heat and Power) generation, which is outcome of DEPB, are considered as dependent variables. But dependent variables including booming of new renewable energy generation due to green energy pricing incentives, the electric power industry restructuring, and electricity tariff and pricing policies were separatively considered. In this study, some policies were proposed reflecting research results of empirical demonstrative analysis, previous studies, overseas cases, etc.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1139_1141
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• 2009

Distributed Generation (DG) is predicted to play a important role in electric power system in the near future. insertion of DG system into existing distribution network has great impact on real-time system operation and planning. It is widely accepted that micro turbine generation (MTG) systems are currently attracting lot of attention to meet customers need in the distributed power generation market In order to investigate the performance of MT generation systems, their efficient modeling is required. This paper presents the modeling and simulation of a MT generation system suitable for grid-connected operation. The system comprises of a permanent magnet synchronous generator driven by a MT. A brief description of the overall system is given, and mathematical models for the MT and permanent magnet synchronous generator are presented. Also, the use of power electronics in conditioning the power output of the generating system is demonstrated. Simulation studies with MATLAB/Simulink have been carried out in grid-connected operation mode of a DG system. The control strategies for grid connected operation mode of DG system is also presented.