Frequency domain design

Bode-Nyquist frequency domain design and Root locus... 

Kuon, J. F., "Multivariable Frequency Domain Design Techniques," Ph.D. dissertation, University of Alberta,... 

Prom our point of view, each approach has its advantages. The first two model-based approaches have a more intuitive time domain performance specification than traditional frequency domain design methods. However, the frequency domain methods require less structural information about the process dynamics. Chapters 6 and 7 present a new frequency domain PID design approach that we feel combines these advantages. This new... 

W.R. Cluett, New frequency-domain design method for PID controllers , pp. 265-271, 1995, with permission from lEE. 

In sections 5.4 and 6.6, compensator design in the. v-plane and the frequency domain were discussed for continuous systems. In the same manner, digital compensators may be designed in the z-plane for discrete systems. 

This tutorial shows how MATLAB can be used to construct all the classical frequency domain plots, i.e. Bode gain and phase diagrams, Nyquist diagrams and Nichols charts. Control system design problems from Chapter 6 are used as examples. 

Multiscale process identification and control. Most of the insightful analytical results in systems identification and control have been derived in the frequency domain. The design and implementation, though, of identification and control algorithms occurs in the time domain, where little of the analytical results in truly operational. The time-frequency decomposition of process models would seem to offer a natural bridge, which would allow the use of analytical results in the time-domain deployment of multiscale, model-based estimation and control. 

Filtering and smoothing are related and are in fact complementary. Filtering is more complicated because it involves a forward and a backward Fourier transform. However, in the frequency domain the noise and signal frequencies are distinguished, allowing the design of a filter that is tailor-made for these frequency characteristics. 

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