Search for dissertations about: "system oscillation"

Showing result 11 - 15 of 114 swedish dissertations containing the words system oscillation.

2. 11. Performance Quantification of Interarea Oscillation Damping Using HVDC

   Author : Joakim Björk; Karl H. Johansson; Lennart Harnefors; Robin Preece; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HVDC transmission control; interarea oscillations; power oscillation damping; small-signal stability; frequency control; controllability; MIMO control; decoupling control; multivariable interaction; Electrical Engineering; Elektro- och systemteknik;

   Abstract : With the transition towards renewable energy, and the deregulation of the electricity market, generation patterns and grid topology are changing. These changes increase the need for transfer capacity. One limiting factor, which sometimes leads to underutilization of the transmission grid, is interarea oscillations. READ MORE

4. 12. Joint Interface Effects on Machining System Vibration

   Author : Qilin Fu; Cornel-Mihai Nicolescu; Tomas Beno; KTH; []
   Keywords : Joint Interface; Vibration; Damping; Chatter; Machining; Carbon NanoComposite; PECVD; HiPIMS; SRA - Production; SRA - Produktion; Järnvägsgruppen - Ljud och vibrationer; Järnvägsgruppen - Ljud och vibrationer;

   Abstract : Vibration problems are still the major constraint in modern machining processes that seek higher material removal rate, shorter process time, longer tool life and better product quality. Depending on the process, the weaker structure element can be the tool/tool holder, workpiece/fixture or both. READ MORE

5. 13. Concepts for Power System Small Signal Stability Analysis and Feedback Control Design Considering Synchrophasor Measurements

   Author : Yuwa Chompoobutrgool; Luigi Vanfretti; Mats Larsson; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wide-area damping control; inter-area oscillations; power system stabilizers; PMU; Järnvägsgruppen - Elsystem; Järnvägsgruppen - Elsystem;

   Abstract : In the Nordic power network, the existence of poorly damped low-frequency inter-area oscillations (LFIOs) has long affected stability constraints, and thereby, limited power transfer capacity. Adequate damping of inter-area modes is, thus, necessary to secure system operation and ensure system reliability while increasing power transfers. READ MORE

6. 14. Security of Time Synchronization for PMU-based Power System State Estimation: Vulnerabilities and Countermeasures

   Author : Ezzeldin Shereen; György Dán; Joe H. Chow; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Phasor measurements unit; Time synchronization; Power system state estimation; Network Security; Time synchronization attacks; Precision time protocol; Machine learning; Electrical Engineering; Elektro- och systemteknik;

   Abstract : Phasor Measurement Units (PMUs) constitute an emerging technology that is essential for various smart grid applications such as phase angle monitoring, power oscillation damping, fault localization, and linear state estimation. To obtain precise PMU measurements of voltage and current phasors, time synchronization in the order of 1 microsecond is typically required. READ MORE

7. 15. Power System Stability Enhancement Using Shunt-connected Power Electronic Devices with Active Power Injection Capability

   Author : Mebtu Bihonegn Beza; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Power Oscillation Damping POD ; energy storage; Adaptive estimation; Static Synchronous Compensator STATCOM ; Recursive Least Square RLS ; Transient Stability Enhancement TSE ; FACTS; Static Var Compensator SVC ;

   Abstract : Power electronic devices such as Flexible AC Transmission Systems (FACTS), both in shunt and series configuration, are widely used in the power system for power flow control, to increase the loading capability of an existing line and to increase the security of the system by enhancing its transient stability. Among the shunt-connected FACTS controllers family, the Static Synchronous Compensator (STATCOM) and the Static Var Compensator (SVC) are two key devices for reinforcing the stability of the AC power system. READ MORE