归了营大学 §5.3对数频率特性(Boe)(6) (6)振荡环节G(s) j IsI .s+ G(jo) 2土j25 -0.3 L(a0)=-20g11-02+1252 L(o dB 0 arctan/25@ 085 360°+ arctan2)∥2 180 <<1 lq(a)≈0°/-360 L(0)≈-40lg(o/an) q(a)≈-180°§5.3 对数频率特性 ( Bode) (6) ⑹ 振荡环节 2 2 2 2 ( ) 20 lg [1 ] [2 ] n n L w w w w w (w) 2 2 2 2 ( ) n n n s s G s w w w n n j G j w w w w w 1 2 1 ( ) 2 2 2 2 360 arctan 2 1 - n wn w w w 2 2 arctan 2 1- n wn w w w 1 wn w L(w) 0 (w) 0 360 1 wn w ( ) L w w wn ( ) 40 lg (w) 180