Search for dissertations about: "voltage stability modal analysis"

Showing result 1 - 5 of 9 swedish dissertations containing the words voltage stability modal analysis.

2. 1. On Modeling and Stability Analysis of Grid-Connected Voltage Source Converters

   Author : Hongyang Zhang; Stefan Östlund; Xiaoming Yuan; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Low-inertia grid; multiple-input multiple-output MIMO ; single-input single-output SISO ; small-signal model; stability analysis; voltage source converters VSCs ; Electrical Engineering; Elektro- och systemteknik;

   Abstract : With increasing deployment of voltage source converters (VSCs) in the grid, instability phenomena due to converter--grid interactions have been observed. Modeling and stability analysis of grid-connected VSCs have become popular research topics. READ MORE

4. 2. Modeling and Control of VSC-HVDC Transmissions

   Author : Hector Latorre; Mehrdad Ghandhari; Luis Rouco; KTH; []
   Keywords : Control Lyapunov Functions; Energy Function; Modal Analysis; Transient Stability; Voltage Stability; VSC-HVDC Transmission.; TECHNOLOGY; TEKNIKVETENSKAP;

   Abstract : Presently power systems are being operated under high stress level conditions unforeseen at the moment they were designed. These operating conditions have negatively impacted reliability, controllability and security margins. FACTS devices and HVDC transmissions have emerged as solutions to help power systems to increase the stability margins. READ MORE

5. 3. 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

6. 4. Fundamental Control Performance Limitations for Interarea Oscillation Damping and Frequency Stability

   Author : Joakim Björk; Karl H. Johansson; Lennart Harnefors; Joe H. Chow; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Power system control; HVDC transmission control; interarea oscillations; power oscillation damping; small-signal stability; fundamental control limitations; frequency stability; hydro power; wind power; non-minimum phase; zero dynamics; eigenvalue analysis; Electrical Engineering; Elektro- och systemteknik;

   Abstract : With the transition towards renewable energy and the deregulation of the electricity markets, the power system is changing. Growing electricity demand and more intermittent power production increase the need for transfer capacity. Lower inertia levels due to a higher share of renewables increase the need for fast frequency reserves (FFR). READ MORE

7. 5. Voltage and power stability of HVDC systems

   Author : Denis Hau Aik Lee; KTH; []
   Keywords : ;

   Abstract : This research work had been motivated by the emergence of multiple HVDC links in close proximity within a power system area, such as those in Southem Scandinavia and Northem Europe. Such system tonfigurations, generally known as multi-infeed HVDC systems, are expected to exhibit voltage and power stability problems when one or more of the constit uent AUDC interconnections are weak. READ MORE