• 제목/요약/키워드: Power quality improvement

검색결과 577건 처리시간 0.033초

수상 태양광발전 적지조사 기법에 관한 연구 (A Study on research of suitable site of Floated PV System)

  • 최형철;김예진;김은기;이종석
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2011년도 제42회 하계학술대회
    • /
    • pp.1400-1401
    • /
    • 2011
  • RPS(Renewable Portfolio Standard) recently with the introduction of a new solar power development as the market expands, land shortage of solar power as an alternative site for installing solar water development has emerged. Solar water dams, reservoirs and water by taking advantage of available solar power development a new concept of private forest land in a way does not involve destruction of the forest land and water resources through efficient use of environmentally friendly energy production and water quality improvement There are a variety of benefits. This paper won the nation's first solar power to enforce the selection of the optimal location for solar power's award for planning theory and research techniques are intended to establish. Award of the solar system through the analysis of a few research-related materials and renewable energy systems project implementation process to establish an initial investigation techniques as well as the existing dam located about fitness will be assessed. In this study, solar water conducting business in the current analysis with considerable planning and installation of solar installation for the economic and environmental cost of the evaluation period and is expected to be able to give you one.

  • PDF

한국의 문화발전에 대한 공공도서관의 역할 (The roles of public libraries on the cultural development of Korea)

  • 박인웅
    • 한국도서관정보학회지
    • /
    • 제21권
    • /
    • pp.291-323
    • /
    • 1994
  • The Result of the study can be summarized as follows : (1) Korean culture and public library look extremely wasted equally. Judging from this fact, I believe that it is impossible for public library can contribute to development of Korean culture. (2) But, public library can contribute to development of culture in the cultural environment that mental desire is prior to physical wants. This cultural environment can be built up with reading of good books. Therefore, if class to reading education and diverse reading education programs can be activated in a large portion of the nationwide public libraries and the majority of a local resident are capable of improving their creativity power, thinking power and imaginative faculty, public library can contribute to produce such cultural circumstances. (3) Quality, culture, a human and mind receive mu6 respect in Korean Society as advanced civil, democratic and industrial society in the future. The Society will be influenced by reason and rational culture will be suitable to this society. Creativity power, thinking-power, imaginative faculty, intelligence and power of information management are demanded to the greatest degree for the development of idea and new technology in the society under the control of rational culture. So, lifelong education with library use is the most fruitful and inexpensive way for the improvement of these powers.

  • PDF

Power Factor Improvement of Distribution System with EV Chargers based on SMC Method for SVC

  • Farkoush, Saeid Gholami;Kim, Chang-Hwan;Jung, Ho-Chul;Lee, Sanghyuk;Theera-Umpon, Nipon;Rhee, Sang-Bong
    • Journal of Electrical Engineering and Technology
    • /
    • 제12권4호
    • /
    • pp.1340-1347
    • /
    • 2017
  • Utilization of Electric Vehicles (EVs) have been growing popularity in recent years due to increment in fuel price and lack of natural resources. Random unexpected charging by home EV charger in distribution is predicted in the future. The power quality problems such as fluctuation of power factor in a residential distribution network was explored with random EV chargers. This paper proposes a high-performance nonlinear sliding mode controller (SMC) for an EV charging system to compensate voltage distortions and to enhance the power factor against the unbalanced EV chargers. For the verification of the proposed scheme, MATLAB-Simulink simulations are performed on 22.9-kV grid. The results show that the proposed scheme can improve the power factor of a smart grid due to the EV chargers on the grid.

부분방전검출 신뢰도 향상을 위한 UHF 센서개선 및 성능검증 (Performance Verification and Improvement of UHF Sensor for the Increasement of the Partial Discharge Detection Reliability)

  • 김원규;김민수;백영식
    • 전기학회논문지
    • /
    • 제63권10호
    • /
    • pp.1461-1466
    • /
    • 2014
  • GIS(Gas Insulated Switchgear) is important power apparatus which have strong dielectric strength, supply electric power and is a part of the power system. Most substation type is configured as GIS. Recently, because of continuous increasement of GIS demand resulted from high quality & big capacity of electric power, the necessity of the preventive & diagnosis system is being expanded gradually. GIS partial discharge occurred on the UHF band is detected effectively by the method to IEC 60270 that recommend to be able to detect the apparent minimum discharge, 5 pC. Additionally, the UHF sensor should be installed to detect PD signal if Partial discharge signal, 5 pC occur in every part of GIS. Currently PD diagnosis system applying UHF sensor for GIS with various voltage level like 154 kV, 345 kV, 765 kV have been operated. And it is necessary to measure and analyze insulation breakdown phenomenon of inside GIS exactly. In this paper, we proposed Fat-dipole patch UHF sensor that is developed and more sensitive, excellent wide-range characteristic than the exising UHF sensor. And we performed KERI (Korea Electrotechnology Research Institute) reference test, which showed the excellent result for the all tests.

D형 리튬 1차 단위전지(Li/SOCl2)용 저가형 과방전 차단회로 개발 (Developments on Low Cost Protection Circuit of Discharge for D-type Non-rechargeable Lithium Batteries(Li/SOCl2))

  • 안만기;정영탁;임재성;노태주
    • 한국군사과학기술학회지
    • /
    • 제21권5호
    • /
    • pp.665-674
    • /
    • 2018
  • In this paper, we propose a development results of a D-type non-rechargeable lithium battery($Li/SOCl_2$) on improvement in a low cost protection circuit of discharge for domestic military power source. According to this study, we describe a new design and product with 8-bit microcontroller in the protection circuit which can estimate state of health of the battery regardless of occurring an initial voltage delay. Also this paper discuss and facilitate development as solution to a safety about the non-rechargeable lithium batteries. As a result, we verified a quality of the protection circuit by a development test and evaluation(DT&E) process.

가속모델의 가속계수 조사 (Investigation of the Acceleration Coefficient in Acceleration Models)

  • 박현종;김성준;박범식;박소미;성시일
    • 품질경영학회지
    • /
    • 제52권1호
    • /
    • pp.135-148
    • /
    • 2024
  • Purpose: This study is to investigate the literature on accelerated tests based on the acceleration model and to provide a compilation of results on the parameters applied in the acceleration model and the test conditions. Methods: This research is conducts a literature review on accelerated tests using the acceleration model, with a focus on test targets, test conditions, and parameter values. The study is organizing the results of this literature review to facilitate their application in the design of reliability tests. Results: A literature review investigated a variety of test targets, test conditions, and parameter values. Conclusion: The results of the literature research conducted revealed various acceleration model parameter. Such literature research on accelerated tests can establish the foundation for reliability test design and contribute to future product development and quality improvement

전력계통의 전압안정도향상을 위한 감시제어시스템 개발 (A Development of Monitoring and Control System for Improved the Voltage Stability in the Power System)

  • 이현철;정기석;박지호;백영식
    • 전기학회논문지
    • /
    • 제62권4호
    • /
    • pp.437-443
    • /
    • 2013
  • This paper was developed a monitoring and control system to use reactive power control algorithm. This algorithm could be improved voltage stability in power system. This method was controlled the voltage for stability improvement, effective usage of reactive power, and the increase of the power quality. PMS(Power Management System) has been calculate voltage sensitivity, and control reactive power compensation device. The voltage control was used to the FACTS, MSC/MSR(Mechanically Switched Capacitors/Reactors), and tap of transformer in power system. The reactive power devices in power system were control by voltage sensitivity ranking of each bus. Also, to secure momentary reactive power, it had been controlled as the rest of reactive power in the each bus. In here, reactive power has been MSC/MSR. The simulation result, First control was voltage control as fast response control of FACTS. Second control was voltage control through the necessary reactive power calculation as slow response control of MSR/MSR. Third control was secured momentary reactive reserve power. This control was method by cooperative control between FACTS and MSR/MSC. Therefore, the proposed algorithm was had been secured the suitable reactive reserve power in power system.

건축행정 서비스 개선방안 연구 (A Study on the Improvement of Architectural Administration Service Program)

  • 황은경;문수영
    • 한국주거학회논문집
    • /
    • 제16권5호
    • /
    • pp.99-106
    • /
    • 2005
  • According the high growth of Korean economy, there are many changes in our life recently. As life quality is improved, the standard of construction is strengthen and subdivision. However, in many steps through which it passes until a building is planned, designed, constructed and completed, there are lots of problems among the law related architecture. Especially, there are many statutes which must be checked related to building permits and much wastes time and money in review because of overlapping laws related architecture. Furthermore, there are limitation of computerization and shortage of human power of administration in architecture. In this study, we propose six improvement programme of administration service in architecture. Through these program, civil applications like housing and economic condition could be improved consistently.

기포분사반응기를 사용한 배연탈황공정의 아황산가스 물질전달 (Mass Transfer of Sulfur Dioxide in Flue Gas Desulfurization Process Utilizing a Jet Bubbling Scrubber)

  • 동종인;나진균;홍지형
    • 한국대기환경학회지
    • /
    • 제8권4호
    • /
    • pp.262-268
    • /
    • 1992
  • The trend of international concerns on environmental conservation and domestic demand of ambient air quality improvement, specially on sulfur dioxide level has resulted in the establishment of mid-term strategy of environmental improvement and stepwise strengthening of emission regulations in this decade in Korea. Development of flue gas desulfurization(FGD) process is becoming an essential task to be accomplished especially for the power plants and large industrial facilities. This study is an initial stage researc focusing on the mass transfer principles in wet type FGD process and the effects of operating variables of a jet bubbling scrubber utilizing limestone slurry on sulfur dioxide removal efficiency. Experimental results showed this type of scrubbing system has some advantages in terms of mass transfer mechanism and removal efficiency. More rigorous research is needed for the reaction system and the comparison with existing FGD processess for the possible development of a process which is compatative in view of installation cost and treatment of by-products.

  • PDF

분지 덱스트린 첨가가 냉동 소프트롤 반죽 및 빵의 저장 중 품질 특성에 미치는 영향 (Effects of Branched Dextrin on the Quality Characteristics of Frozen Soft Roll Dough and its Bread during Storage)

  • 박진희;임춘선;김일환;김문용
    • 한국식품조리과학회지
    • /
    • 제27권5호
    • /
    • pp.507-522
    • /
    • 2011
  • In this study, samples of wheat flour and dough were prepared by adding of 1, 3, or 5% branched dextrin, which is produced from the amylopectin of waxy corn starch using a cyclization reaction with a branching enzyme. The samples were then evaluated qualitatively in terms of farinogram, viscogram, and extensogram characteristics. The fermentation power of dough expansion, extensogram characteristics, specific volume, baking loss, external/internal surface appearance, and sensory qualities were also examined after 4 weeks of storage at -20$^{\circ}C$ to determine the effect on freeze-thaw stability and quality improvement of branched dextrins in the soft roll bread formulation. Furthermore, the samples along with a control were compared regarding their quality characteristics, including changes in moisture content, water activity, color, and textural characteristics during a storage period of 4 days at 20$^{\circ}C$ to determine the effect on preventing retrogradation of the branched dextrin. As the branched dextrin content increased, area and extensibility increased, whereas water absorption, fermentation power of dough expansion, resistance/extensibility ratio, baking loss, and brownness of the crust decreased. However, the control group presented significantly higher peak viscosity, resistance, specific volume, taste, overall acceptability, moisture content, water activity, springiness, cohesiveness, and resilience values than those of the branched dextrin samples, whereas lightness, hardness, and chewiness showed the reverse effect. As the storage period increased, lightness, hardness, and chewiness increased, whereas cohesiveness decreased. In conclusion, the results indicate that adding 1~3% branched dextrin into a soft roll bread formulation from frozen dough had no positive effect on freeze-thaw stability or preventing retrogradation but may provide good nutritional properties.