PD Control Second Order Type 1 Step response and Root Locus
Cuthbert Nyack
The applet here show the step response and root locus of a type 1 second
order system with PD control. The continuous system is always stable
The transfer functions of the controller Gc(s) and system Gs(s)
are combined with a sampler and ZOH to obtain a forward
transfer function:-
G(z) = (1 - z-1)Z{Gc(s)Gs(s)/S}
The closed loop transfer function is then:-
Gcs(z) = G(z)/(1 + G(z).
eg parameters (5.0, 3.0, 1.6, 0.05, 2.0). Good correspondence between
continuous and sampled systems. Increased Td has damped out
transient.
eg parameters (5.0, 3.0, 0.1, 0.05, 2.0).
Gif image below show how the applet should appear.
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COPYRIGHT © 2006 Cuthbert Nyack.