Accession Number : ADA064483


Title :   Feedback System Theory


Descriptive Note : Annual rept. for year ending 31 Oct 78


Corporate Author : COLORADO UNIV AT BOULDER DEPT OF ELECTRICAL ENGINEERING


Personal Author(s) : Horowitz, Isaac M


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a064483.pdf


Report Date : Nov 1978


Pagination or Media Count : 12


Abstract : In Quantitative Feedback Synthesis, bounds on plant uncertainty and on the system performance are specified. The minimum feedback is used which satisfies the latter over the range of uncertainty. Quantitative design has been extended to linear time invariant systems: (1) with nonminimum-phase (nmp) unstable plants with gain uncertainty. In the optimum design the gain factor uncertainty is maximized for which the specifications are satisfied; (2) parallel nmp plants whose output can be individually measured and processed, to achieve a parallel combination which is minimum-phase over the range of uncertainty, or if not possible, which is less strongly nmp. (3) Cascade plants in which 'plant modification' is possible by means of internal feedback. An added constraint is that the increase in plant interval variable ci rms value equal to or less than LAMBDA sub i. Such internal feedback permits significant decrease in loop bandwidths and thereby the effect of sensor noise. (4) A problem heretofore intractable to Quantitative Synthesis has been the Multiple Input-Output (multivariable) system. This problem has now been solved for plants with significant uncertainty and interaction. A remarkable feature is that the design procedure involves the design of a number of distinct, separate single- loop problems with no need for iteration. Constraints on the plant are less stringent than in other synthesis techniques which cannot handle significant parameter uncertainty (Author)


Descriptors :   *FEEDBACK , *CONTROL THEORY , *LOOPS , LINEAR SYSTEMS , QUANTITATIVE ANALYSIS , PHASE , NOISE , BANDWIDTH , MULTIPLE OPERATION


Subject Categories : Numerical Mathematics
      Cybernetics


Distribution Statement : APPROVED FOR PUBLIC RELEASE