Sökning: "Passivity"

Visar resultat 11 - 15 av 57 avhandlingar innehållade ordet Passivity.

1. 11. Analysis of VSC-based HVDC systems

   Författare :Georgios Stamatiou; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HVDC; MMC; MTDC; Poor damping; Symbolic eigenvalue expressions; Droop control; Passivity Analysis; Net damping; Frequency Domain Analysis; VSC;

   Sammanfattning : The main objective of this thesis is to perform stability and control studies in the area of VSC-HVDC systems. A major part of the investigation focuses on the development of procedures, whose aim is to understand, explain and avoid poorly-damped conditions or instability that may appear due to dc-side resonances, which stem from the interaction of converters and passive elements in such systems. LÄS MER

3. 12. Converter interactions in VSC-based HVDC systems

   Författare :Georgios Stamatiou; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Symbolic eigenvalue expressions; Frequency Domain Analysis; Droop control; Net damping; VSC; Passivity Analysis; MTDC; Poor damping; HVDC;

   Sammanfattning : The main objective of this thesis is to perform stability and control studies in the area of VSC-HVDC. A major part of the investigation focuses on the explanation of poorly-damped conditions and instability that are linked to dc-side resonances. LÄS MER

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

   Författare :Yujiao Song; Chalmers tekniska högskola; []
   Nyckelord :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;

   Sammanfattning : 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. LÄS MER

5. 14. Haptic Feedback Control Methods for Steering Systems

   Författare :Tushar Chugh; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; passivity and coupled stability; torque and position overlay; Haptic feedback; impedance and admittance control; system identification; steering system;

   Sammanfattning : Haptic feedback from the steering wheel is an important cue that defines the steering feel in the driver-vehicle interaction. The steering feedback response in an electric power assisted steering is primarily dependent on its control strategy. LÄS MER

7. 15. Use of local electrochemical techniques for corrosion studies of stainless steels

   Författare :Nuria Fuertes; Rachel Pettersson; Mari Sparr; Ulf Kivisäkk; Yolanda Hedberg; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Stainless steel; passive film; thermal oxides; work function; pickling; SKPFM; SVET; XPS; AES; Teknisk materialvetenskap; Materials Science and Engineering;

   Sammanfattning : The excellent corrosion resistance of stainless steels arises from the presence of a passive film on its surface. Above 10.5wt% Cr a chromium oxide of 1-3 nm is formed on the surface of the metal that in case of damage will reform and hinder further dissolution of the metal. LÄS MER