Bode plot and Step Response for 3 Real Poles and 1 Real Zero

Cuthbert Nyack
This applet shows the Bode plot and gain and phase margins for the 3p and 3p1z case and the closed loop poles of the 3p1z system.
The eg parameters (7.92, 1.0, 1.0, 2.0, 3.0, 1.0, 1.0) show the effect of z on the system. The 3 pole system has phase and gain margin of 0 while the system with the zero has a phase margin of 25.8° at ~1.72rad/s, the gain margin is undefined because the phase lag does not go below -180°.

The eg parameters show the effect of the zero on the gain and phase margins. With no zero both gain and phase margins are ~0.
(8.0, 1.0, 1.0, 1.0, 4.0, 1.0, 1.0) zero at -4 Gm = 12.07dB, Pm = 21.25°
(8.0, 1.0, 1.0, 1.0, 3.6, 1.0, 1.0) zero at -3.6 Gm = 15.61dB, Pm = 23.13°°
(8.0, 1.0, 1.0, 1.0, 3.0, 1.0, 1.0) zero at -3 Gm = N/D, Pm = 26.59°
(8.0, 1.0, 1.0, 1.0, 2.0, 1.0, 1.0) zero at -2 Gm = N/D, Pm = 34.44°




Gif image below shows how applet should appear.

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COPYRIGHT 2006 Cuthbert Nyack.