Fall 2001 Non-minimum Phase Systems Bode plots are particularly complicated when we have non-minimum tems A system that has a pole/zero in the RhP is called non-minimum ase The reason is clearer once you have studied the Bode Gain Phase relationship Key point: We can construct two(and many more) systems that have identical magnitude plots, but very different phase diagrams Consider Gi(s)=s+2 and G2(s)=s s+2 --=-“""--- Freq Figure 4: Magnitude plots are identical, but the phase plots are dramatically different. NMP has a 180 deg phase loss over this frequency rangeFall 2001 Non-minimum Phase Systems • Bode plots are particularly complicated when we have non-minimum phase systems – A system that has a pole/zero in the RHP is called non-minimum phase. – The reason is clearer once you have studied the Bode Gain￾Phase relationship – Key point: We can construct two (and many more) systems that have identical magnitude plots, but very different phase diagrams. • Consider G1(s) = s+1 s+2 and G2(s) = s−1 s+2 10−1 100 101 102 10−1 100 Freq |G| MP NMP 10−1 100 101 102 0 50 100 150 200 Freq Arg G MP NMP Figure 4: Magnitude plots are identical, but the phase plots are dramatically different. NMP has a 180 deg phase loss over this frequency range