http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 주제어 : positive and negative sequence compensation (검색결과 4 건)
- 무료
- 기관 내 무료
- 유료
-
3상 불평형 전원 시스템의 새로운 위상각 검출기법을 이용한 순간전압보상기의 해석 및 제어
이승요,고재석,목형수,최규하 전력전자학회 1999 전력전자학회 논문지 Vol.4 No.3
3산 전력 시스템에서 불평형 전원의 전압은 대칭좌표법에 의하여 정상, 역상, 영상성분으로 각각 분해 될 수 있고 또한 전력 시스템에 중성선이 없는 경우 영상성분은 부하측에 나타나지 않게 된다. 따라서 중성선이 없는 불평형 시스템에서는 전원측의 역상성분만을 검출하여 보상함으로써 부하측에 평형된 전압을 공급할 수 있을 뿐만 아니라 정상성분의 크기를 제어함으로써 부하에 인가되는 전압의 크기를 조정하는 것이 가능하다. 아울러 이러한 불평형 전압에 의한 각 대칭분은 3상 2상 변환을 통한 동기좌표축상에서의 효율적인 검출이 가능한데, 본 논문에서는 전원의 불평형 성분을 동기좌표축 상에서 순시적으로 검출하여 이를 보상하고 부하의 전압조정 기능 역시 수행하는 순간전압보상기의 보상 알고리즘 및 이때 좌표변환시 필요한 전원의 위상각 정보를 전원의 정상성분에 일치시키는 새로운 위상각 검출 알고리즘을 제안한다. 제안된 보상 시스템의 성능 및 특성을 시뮬레이션을 통하여 해석하고 실험으로써 검증하였다. Unbalanced source voltage in the 3-phase power system is decomposed into positive, negative and zero sequence c components. Also, assuming there is no neutral path in the system, the zero sequence component is not shown on the l load side. Therefore, in the unbalanced power system without neutral path. it is possible to provide balanced voltage to t the load side by compensating negative sequence component and also to regulate the voltage amplitude by controlling t the positive sequence component. In addition, the symmetrical components due to voltage unbalance can be effectively d detected on the synchronous reference frame by using dlongleftarrowq transformation. In this paper, an algorithm not only c compensating unbalanced source voltage by canceling the negative sequence component on the synchronous reference f frame but also maintaining load voltages constantly is proposed. Also a novel method for phase angle detection s synchronized by positive sequence component under unbalanced source voltage is suggested and this detected phase a angle is used for d-q transformation. The performances and characteristics of the proposed compensating system are a analyzed by simulation and verified through experimental results.
-
Droop Control Scheme of a Three-phase Inverter for Grid Voltage Unbalance Compensation
Hongpeng Liu,Jiajie Zhou,Wei Wang,Dianguo Xu 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.4
The stability of a grid-connected system (GCS) has become a critical issue with the increasing utilization of renewable energy sources. Under grid faults, however, a grid-connected inverter cannot work efficiently by using only the traditional droop control. In addition, the unbalance factor of voltage/current at the common coupling point (PCC) may increase significantly. To ensure the stable operation of a GCS under grid faults, the capability to compensate for grid imbalance should be integrated. To solve the aforementioned problem, an improved voltage-type grid-connected control strategy is proposed in this study. A negative sequence conductance compensation loop based on a positive sequence power droop control is added to maintain PCC voltage balance and reduce grid current imbalance, thereby meeting PCC power quality requirements. Moreover, a stable analysis is presented based on the small signal model. Simulation and experimental results verify the aforementioned expectations, and consequently, the effectiveness of the proposed control scheme.
-
Droop Control Scheme of a Three-phase Inverter for Grid Voltage Unbalance Compensation
Liu, Hongpeng,Zhou, Jiajie,Wang, Wei,Xu, Dianguo The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.4
The stability of a grid-connected system (GCS) has become a critical issue with the increasing utilization of renewable energy sources. Under grid faults, however, a grid-connected inverter cannot work efficiently by using only the traditional droop control. In addition, the unbalance factor of voltage/current at the common coupling point (PCC) may increase significantly. To ensure the stable operation of a GCS under grid faults, the capability to compensate for grid imbalance should be integrated. To solve the aforementioned problem, an improved voltage-type grid-connected control strategy is proposed in this study. A negative sequence conductance compensation loop based on a positive sequence power droop control is added to maintain PCC voltage balance and reduce grid current imbalance, thereby meeting PCC power quality requirements. Moreover, a stable analysis is presented based on the small signal model. Simulation and experimental results verify the aforementioned expectations, and consequently, the effectiveness of the proposed control scheme.
-
Tan Luong Van,Trong Huan Nguyen,Nhut Minh Ho,Xuan Nam Doan,Thanh Hai Nguyen 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5
This paper proposes a control strategy of the voltage compensation based on a nine switch converter (NSC) to enhance a low-voltage ride-through (LVRT) capability for a doubly fed induction generator (DFIG) wind turbine system. The nine switch converter connected to a stator-side of the DFIG can enable to compensate the voltage response of the system during the grid faults. For series voltage source converter (VSC), a control algorithm consisting of dual voltage controllers is implemented for the two sequence components in the dq synchronous reference frame. As for shunt voltage source converter (VSC), a control algorithm is carried out in the dq reference frame and incorporates both an inner current control loop and an outer voltage control loop. The effectiveness of the proposed methods is verified by the simulation results for the 2 [MW]-DFIG wind turbine system under unbalanced grid voltage conditions.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
