Bode and Nyquist plots analyse stability and margins.
Frequency response G(jω) shows gain and phase vs frequency. Bode plots (log scales) and Nyquist plots analyse stability margins and bandwidth; closed-loop bandwidth relates to speed and noise sensitivity. Experimental frequency response can model unknown plants.
Sweeping a sine input through a system measures its Bode plot.
Bode and Nyquist plots show stability and margins from the frequency response, which is how many loops are designed in practice.
Bode and Nyquist plots analyse stability and margins.
Bode and Nyquist plots show stability and margins from the frequency response, which is how many loops are designed in practice.
The magnitude and phase of the frequency response on logarithmic scales, which helps design and assess margins.
The path of the open-loop frequency response in the complex plane, which can reveal instability encirclements.
Typical applications include checking the stability of a motor speed loop using its Bode plot, reading the crossover frequency of a controller for bandwidth and using a Nyquist plot to assess a loop with a time delay.
Study "Root locus" first (topic 52 of 101 in Signals, Control & Comms). It covers the groundwork this topic builds on.
Resonant peak M_r. Bandwidth. Low-frequency gain sets accuracy.
Sweeping a sine input through a system measures its Bode plot.
The next topic is "Gain and phase margin", which builds directly on this one.
It is classed as Intermediate in Signals, Control & Comms (topic 53 of 101). It is an intermediate topic. Work through the beginner topics in Signals, Control & Comms first.
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