Search for dissertations about: "HVDC control"

Showing result 11 - 15 of 52 swedish dissertations containing the words HVDC control.

2. 11. A Multichoice Control Strategy for a VSC-HVdc

   Author : Hector F. Latorre; Mehrdad Ghandhari; Lennart Söder; Kjetil Uhlen; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Control Lyapunov Function; Modal Analysis; Power Oscillation Damping; Transient Stability; Voltage Stability; VSC-HVdc; Electrical engineering; Elektroteknik;

   Abstract : Utilization of power electronics based controllable systems (or devices) in transmission systems has opened new opportunities for the power industry to optimize utilization of the existing transmission systems, and at the same time to keep high system reliability and security. As a member of these controllable systems, Voltage Source Converters-based High Voltage direct current (VSC-HVdc) systems have the ability to rapidly control the transmitted active power, and also to independently exchange reactive power with transmissions systems. READ MORE

4. 12. On the robust stability analysis of VSC-HVDC systems

   Author : Yujiao Song; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; symbolic eigenvalue expressions; distributed parameter cable model; AC-grid interaction; VSC-HVDC system; passivity theorem; small gain theorem; Nyquist stability analysis;

   Abstract : This thesis focuses on small signal stability analysis of VSC-HVDC systems, emphasizing the system stability robustness with regard to the connected AC-grid and the distributed parameter DC-grid model respectively. In addition, for strong AC-grid connected systems, analytical eigenvalue expressions are provided to investigate the impact of physical or control parameters on the system stability for both two-terminal and multi-terminal VSC-HVDC systems. READ MORE

5. 13. Configuration study of large wind parks

   Author : Stefan Lundberg; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; production cost; PCC; power quality; offshore; HVDC; wind parks; DC DC converters; control; losses; configurations; flicker; energy capture;

   Abstract : In this thesis, layouts of various large-scale wind parks, using both AC as well as DC, are investigated. Loss modelling of the wind park components as well as calculations of the energy capture of the turbines using various electrical systems are performed, and the energy production cost of the various park configurations is determined. READ MORE

6. 14. Analysis of dc-network stability of VSC-based HVDC grids

   Author : Gustavo Pinares; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; power dependent admittance; resonance; HVDC; passivity; Multi-terminal HVDC system; VSC; dc-network stability;

   Abstract : This thesis presents a modelling approach for the investigation of dc-network stability in HVDC grids. It consists on dividing the system under analysis into subsystems such that their individual impact on the stability of the overall system can be studied. READ MORE

7. 15. On Efficient Transmission Balancing Operation : Capturing the Normal State Frequency and Active Power Dynamics

   Author : Martin Nilsson; Lennart Söder; Julia Matevosyan; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Active Power Dynamics; Frequency Control; Normal State; Power System Balancing; Transmission System Operator; Electrical Engineering; Elektro- och systemteknik;

   Abstract : In an electric power system, there will always be an electric balance. Nevertheless, System Operators (SOs) often uses the term imbalance. Here, the term imbalance refers to the difference between trades and real-time measurements. READ MORE