8-8 discusses the stability analysis of closed-loop systems using the
Nyquist stability criterion, and Section
8-9 treats the relative stability analysis of closed-loop
systems Measures of relative stability such as phase margin and gain margin are
introduced here. The correlation between the transient response and frequency
response is also discussed. Section
8-10 presents a method for obtaining the closed-loop
frequency response from the open-loop frequency response by use of the M and N
circles. Use of the Nichols chart is also discussed for obtaining the closed-loop frequency
response. Finally, Section
8-11 deals with the determination of the transfer function
based on an experimental Bode diagram.