q Kq(w/r) large near w=r: |N0(rejq)| will be small if |P(jw)| is small near w=r and |M0(rejq)| will be small if |P(jw)| is large near w=r.
• Large q: Kq(w/r) very large near w=r and small otherwise. Hence |N0(rejq)| and |M0(rejq)| will essentially be
determined by |P(jw)| in a very narrow frequency range near w=r when q is large.
•
•
•
• On the other hand, when q is small, a larger range
of frequency response |P(jw)| around w=r will have affect on the
value |N0(rejq)| and |M0(rejq)|(This, in fact, will
imply that a right-plane zero (pole) with a much larger real part than
the imaginary part will have much worse effect on the performance
than a right-plane zero (pole) with a much larger imaginary part than
the real part).
Figure 16.6: Kq(w/r) vs. normalized
frequency w/r