Sökning: "feedforward"

Visar resultat 6 - 10 av 78 avhandlingar innehållade ordet feedforward.

  1. 6. Active Noise Control of Enclosed Sound Fields Optimising the Performance

    Författare :Per Sjösten; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; optimising actuator and sensor positions; hybrid controller for anc; fast feedforward algorithm; multiple-error algorithm; active noise control; complex lms; multichannel feedforward algorithm; simulated annealing; mean-field annealing; multiple-reference controller;

    Sammanfattning : Active noise control is the art of reducing a primary unwanted sound field by interference with an actively created secondary sound field. To achieve high reduction, it is crucial to obtain both temporal and spatial matching between the primary and the secondary sound fields. LÄS MER

  3. 7. Estimation and Control of Resonant Systems with Stochastic Disturbances

    Författare :Peter Nauclér; Torsten Söderström; Anders Robertsson; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vibration control; stochastic control; stochastic systems; feedforward control; Wiener filtering; Kalman filtering; wave separation; unbalance estimation; nonlinear regression; Automatic control; Reglerteknik;

    Sammanfattning : The presence of vibration is an important problem in many engineering applications. Various passive techniques have traditionally been used in order to reduce waves and vibrations, and their harmful effects. Passive techniques are, however, difficult to apply in the low frequency region. LÄS MER

  4. 8. Robust Sound Field Control for Audio Reproduction : A Polynomial Approach to Discrete-Time Acoustic Modeling and Filter Design

    Författare :Lars-Johan Brännmark; Anders Ahlén; Mikael Sternad; Mathias Johansson; Rodney Kennedy; Uppsala universitet; []
    Nyckelord :Acoustic signal processing; equalizers; error modeling; feedforward control; interpolation; loudspeakers; multivariable filters; polynomials; robustness; sound fields;

    Sammanfattning : This thesis is concerned with the design and analysis of robust discrete-time filters for audio equalization and sound field control in real reverberant environments. Inspired by methods in polynomial control theory, a unified framework for acoustic modeling and filter design is developed. LÄS MER

  5. 9. Coordinated Control of HVDC Links in Transmission Systems

    Författare :Robert Eriksson; Lennart Söder; Kjetil Uhlen; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; coordinated control; dynamic security; exact-feedback linearization; feedforward control; HVDC poser modulation; Electric power engineering; Elkraftteknik;

    Sammanfattning : Dynamic security limits the power transfer capacity between regions and therefore has an economic impact. The power modulation control of high-voltage direct current (HVDC) links can improve the dynamic security of the power system. LÄS MER

  7. 10. Fixed-Feedback SISO Adaptive Control

    Författare :Magnus Nilsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Two-Degrees-of-Freedom Control; Feedforward Control; Adaptive Control;

    Sammanfattning : Adaptive control is an attractive method to solve control problemssince the tedious task of identifying process behavior to find asuitable design for the controller is taken care of by the adaptivecontroller itself. It may be difficult, however, to guaranteerobustness (in the sense of desired disturbance attenuation andstability margins) for traditional adaptive schemes since theircorresponding loop gain is time varying. LÄS MER