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We demonstrated silicon nanoparticle synthesis using a novel CO2 laser pyrolysis reactor. The reactor was designed to have an elongated reaction zone more than 10 times longer than conventional laser pyrolysis systems by aligning the laser beam and precursor gas stream in the same direction within the simple tubular reactor. Experimental results showed that the elongated reaction zone contributed to production of silicon nanoparticles using SiH4 gas and influenced the size distribution of nanoparticles. Since the proposed reactor utilized the laser beam more efficiently without focusing the laser beam, it would be beneficial to large-scale production tolerating higher power CO2 lasers. Silicon nanoparticle synthesis mechanisms using a proposed reactor and synthesized nanoparticles were discussed in detail based on X-ray diffraction and transmission electron microscopy measurements.

In Korea, high generation cost and environmental pollution are also discussed at island off-grid. In this situation, remote microgrid (MG) can be solution to solve the problems. Remote MG is small power system, which consists of renewable sources, energy storage system, and load. It is possible to reduce generation cost by introducing remote MG into island areas. KEPCO (Korea Electric Power Corporation) is also proceeding study on remote MG and doing project about remote MG. KEPCO had designed demonstration site for remote MG and constructed the site at island named ‘Geocha-Island’ which is located in south-western side of Korea. This study deals with the system design by economic evaluation. Secondly, construction of the site is introduced. Finally, operation strategy of the system is introduced.

MicroGrids are small power supply system located on-site that can supply both the electricity and the hot-water simultaneously. MicroGrid system that consists of Distributed Energy Resources system, such as wind, solar, fuel-cell and co-generation, has been developed greatly during the last 10 years. It's concept assumes a cluster of loads and microsources operating as a single controllable system that provides a new paradigm for defining the operation of distributed generation. For example this cell could be controlled as a single dispatchable load, which can respond in seconds to meet the needs of the transmission system. It can be also designed to meet their special need; such as, enhance local reliability, reduce feeder losses. This paper introduces the case study of engineering to construct Microgrid with actual loading in KEPRI

As Smart Grid is being applied to distribution power system, SDMS (Smart Distribution Management System) has been developed for distribution power system management. Distribution power system has been changed from radial system to closed loop or mesh systems due to connection of distributed generation growth. Data from distribution equipments which are installed at distribution line must be accurate for the performance of SDMS. This study analyzes the voltage measurement data from distribution equipment. However, the results of the analysis confirm to have some errors in voltage measurement data from distribution equipment. These errors come from aging of voltage sensor in distribution equipment and inaccurate data transfer to FRTU through the controller. The main problem is not to assess the voltage measurement data after first installation of distribution equipment at the distribution line. This paper shows the voltage measurement accuracy assessment system that is to evaluate the voltage measurement data from distribution equipment on liveline to solve the problem. This system had a field test to check its performance. It will be used to assess the performance of distribution equipments and smart distribution equipments. (4 pages)

The grid-interconnected Microgrid must be able to operate without the utility's grid to supply electricity in case of outage. To operate in standalone mode, the Microgrid must control electricity demand or supply to maintain the frequency. The Microgrid EMS (Energy Management System) could control supply and demand with the AGC (Auto Generation Control) function using a communication line. Note, however, that the period of AGC is too slow to maintain the frequency if there is rapid variation in loads or generation. Moreover, the transition of operation mode could fail if there is too much power flow at PCC (Point of Common Coupling). In this paper, we propose a method of improving the stability of the grid-interconnected Microgrid using BESS (Battery Energy Storage System) and super capacitor. The cooperative control method between BESS and super capacitor uses droop, which is used at the generator. BESS could operate as UPC (Unit Power Control) or FFC (Feeder Flow Control) depending on Microgrid's operation strategy. We simulate the cooperative control method using PSCAD/EMTDC to verify the validity of the method. As a result, Microgrid's stability is improved using the cooperative control method, and the life span of BESS could be prolonged.

We report the extraction of silicon via a carbothermal reduction process using a CO2 laser beam as a heat source. The surface of a mixture of silica and carbon black powder became brown after laser beam irradiation for a few tens of seconds, and clear peaks of crystalline silicon were observed by Raman shift measurements, confirming the successful carbothermal reduction of silica. The influence of process parameters, including the laser beam intensity, radiation time, nitrogen gas flow in a reaction chamber, and the molar ratios of silica/carbon black of the mixture, on the carbothermal reduction process is explained in detail.