Search for dissertations about: "small signal stability"

Showing result 1 - 5 of 63 swedish dissertations containing the words small signal stability.

2. 1. Wind Power - Added Value for Network Operation

   Author : Nayeem Ullah; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; torsional oscillation; reactive power ancillary service; voltage stability; power system simulator.; STATCOM; non-minimum phase system; Variable speed wind turbine; frequency control; sensitivity analysis; transient stability; small-signal stability;

   Abstract : This dissertation deals with the investigation on different value added properties of variable speed wind turbines (VSWT) that stem from the flexible controllability of converter interfaced wind turbines (WT). Improvements in voltage and transient stability of a nearby grid, small-signal stability improvement on the power system, frequency control support for the network operation, as well as thetechnical and the economic issues related to the reactive power ancillary service provision, are among the issues covered. READ MORE

4. 2. 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

5. 3. On Stability and Surge in Turbocharger Compressors

   Author : Bertrand Kerres; Andreas Cronhjort; Mihai Mihaescu; Jörg Seume; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbocharger; Radial Compressor; Stability; Surge; Hurst exponent; Fractals; Machine Design; Maskinkonstruktion;

   Abstract : Turbochargers are used on many automotive internal combustion engines to increase power density. The broad operating range of the engine also requires a wide range of the turbocharger compressor. At low mass flows, however, turbo compressor operation becomes unstable and eventually enters surge. READ MORE

6. 4. Real-time signal processing in MEMS sensor-based motion analysis systems

   Author : Jiaying Du; Maria Lindén; Helena Grip; Mälardalens högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; elektronik; Electronics;

   Abstract : This PhD thesis focuses on real-time signal processing for hardware-limited micro-electro-mechanical system (MEMS) sensor-based human motion analysis systems. The aim of the thesis is to improve the signal quality of MEMS gyroscopes and accelerometers by minimizing the effects of signal errors, considering the hardware limitations and the users' perception. READ MORE

7. 5. 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