Unformatted text preview: D2 s has better performance. ii For noise rejection at high frequency range, we have slim Gs = slim s83 Hence simple calcula!1 !1 tion gives lim D Gs = lim 1:2327sGs = lim 9:8616 2520 lim D2 Gs = slim 1:4065sGs = slim 11:s2 s!1 !1 !1 Because noise rejection requires DGs to be small, D1 s has better performance. But overall D1 s and D2 s have similar sensitivity and noise rejection performances.
1 s!0 s s!0 s s!1 s!1 s2 4. Rewrite Ls = DGs = D1 sG1 s, where 40Ds bs + 1 D1 s = 2 ; G1 s = : s + 2s + 10s + 8 s+a T T G T Then Sa = SG1 Sa 1 , and SbT = SG1 SbG1 with 2 + + 10s s+a 1 T = s2 + 2s +s102s+ 8s + +840bs+ 1Ds : SG1 = 1 + DGs s a + Because dG1 bs + s = , s + a12 ; dG1 = , s + a ; da db we obtain
G Sa 1
a = ,s + a; Sb G1 = bs + 1 bs :...
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- Fall '07
- PID compensator