Search for dissertations about: "unity power factor"

Showing result 1 - 5 of 13 swedish dissertations containing the words unity power factor.

  2. 1. Study of Induction Machines with Rotating Power Electronic Converter

    Author : Yanmei Yao; Chandur Sadarangani; Zi-Qiang Zhu; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Brushless induction machine; efficiency improvement; optimum efficiency; rotating power electronic converter; unity power factor; variable power factor; wound rotor induction machine; Electrical Engineering; Elektro- och systemteknik;

    Abstract : This thesis investigates a novel induction machine topology that uses a rotating power electronic converter. Steady-state and dynamic performance of the topology is studied to understand its operational principle. Furthermore the potential of improving its efficiency and power factor is investigated. READ MORE

  4. 2. Analysis and Control Aspects of Brushless Induction Machines with Rotating Power Electronic Converters

    Author : Naveed ur Rehman Malik; Chandur Sadarangani; Luca Peretti; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Doubly-fed induction generator; extended vector control; induction machine; internal model control; Lindmark concept; low voltage ride through; passive resistive network; rotating power electronic converter; rotating exciter; symmetrical faults; synchronous machine; unity power factor; unsymmetrical faults; vector control; wind turbines.; Järnvägsgruppen - Elsystem; Järnvägsgruppen - Elsystem;

    Abstract : This thesis deals with the steady-state, dynamic and control aspects of new type of brushless configuration of a doubly-fed induction machine in which the slip rings and carbon brushes are replaced by rotating power electronics and a rotating exciter. The aim is to study the stability of this novel configuration of the generator under mechanical and grid disturbances for wind power applications. READ MORE

  5. 3. Modelling, Analysis, and Control Aspects of a Rotating Power Electronic Brushless Doubly-Fed Induction Generator

    Author : Naveed ur Rehman Malik; Chandur Sadarangani; Torbjörn Thiringer; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Brushless doubly-fed induction generator; dual vector control; dynamic model; induction machine; internal model control; Lindmark concept; low-voltage ride-through; passive resistive network; rotating power electronic converter; rotating exciter; symmetrical faults; synchronous machine; thermal model; unity power factor; unsymmetrical faults; vector control; wind turbines.; Electrical Engineering; Elektro- och systemteknik; Energy Technology; Energiteknik;

    Abstract : This thesis deals with the modeling, analysis and control of a novel brushlessgenerator for wind power application. The generator is named as rotatingpower electronic brushless doubly-fed induction machine/generator (RPEBDFIM/G).A great advantage of the RPE-BDFIG is that the slip power recoveryis realized in a brushless manner. READ MORE

  6. 4. 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

  7. 5. Run-Up Transient Analysis for Salient Pole Wound Field Synchronous Motors : Field winding and power electronics implications for a smoother and cooler asynchronous start

    Author : Roberto Felicetti; Urban Lundin; Andreas Binder; Uppsala universitet; []
    Keywords : apparent resistance; cable modeling; current control; transmission line model; eddy currents; field winding; frequency analysis response; Fourier Transform; impedance mismatch; main inductance; overvoltage; parasitic capacitance; partial discharge; quality factor; ringing; slew rate; stray inductance; voltage gradient; winding resonance frequency; asynchronous start; run-up; torque ripple; reluctance torque; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

    Abstract : Salient Pole Wound Field Synchronous Machines have better efficiency at full load than asynchronous machines of the same capability. Moreover, where asynchronous machines need inherently to draw a magnetizing current from the grid, Salient Pole Wound Field Synchronous Machines can work efficiently at unity power factor. READ MORE