1,722,838 research outputs found
Sun-Min,Kim
No full text학위논문(석사)아주대학교 일반대학원 :전자공학과,2012. 2제 1 장 서론 1
제 2 장 분산전원 시스템 3
2.1 분산전원 시스템의 필요성 3
2.2 분산전원 시스템의 계통연계 기준 3
2.3 계통 전압의 왜곡현상 5
제 3 장 제안하는 PLL 시스템 7
3.1 전체시스템 구성 7
3.2 PLL 시스템의 선형화 모델 8
3.3 저차 고조파 영향 12
3.4 전차원 상태관측기 설계 14
제 4 장 시뮬레이션 16
제 5 장 결론 22
참고문헌 23MasterIn a grid connected power conversion system, the phase angle information of a grid voltage is very essential for supplying power to the grid since it is used for active and reactive power control. A Phase Locked Loop (PLL) system is used and should be robust because often the actual grid voltages are usually distorted by unexpected harmonics. However, conventional PLL systems have steady state errors when distorted voltages are used as a PLL input. Furthermore, using this distorted phase angle in the power control could reduce the output power quality. In this paper, the grid voltages are separated into fundamental and harmonic components and a virtual phase voltage is generated from the fundamental component using a Full Order Observer (FOO). Two virtual voltages are used as an input for the PLL system so the phase angle errors can be reduced and the output power quality can be improved. The dynamic characteristics of the PLL system are designed using the modeling method to improve the dynamic response and stability of the whole system. The performance of the proposed method has been verified by a comparative analysis to the conventional PLL system. It is concluded the proposed method works well
Sun-Min Kim, organ
Full text linkKyu-Yung ChinNicolaus BruhnsMarcantonio CavazzoniGirolamo CavazzoniJohann Sebastian BachGeorg BohmJohannes Brahm
Sun-Min Kim, organ
Full text linkDieterich BuxtehudeJan Pieterszoon SweelinckLouis-Nicolas ClerambaultGirolamo FrescobaldiFelix Mendelssohn BartholdyJohann Sebastian Bac
Guest Artist Recital, Dr. Sun Min Kim, piano
Full text linkAssistant professor of piano, Indiana University of Pennsylvani
Active noise control algorithm based on noise frequency estimation
No full text학위논문(석사) - 한국과학기술원 : 기계공학과, 1998.2, [ iii, 66 p. ]한국과학기술원 : 기계공학과
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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