2015/11/14 尼奎斯特图Nyquist plot、polar plot)定义 一（对数幅频图） IGjo)lvs∠G(Ujo) lm◆ Im Uo) 9(1) Re 0 Re G(jw) G60m) GG2） [极坐标系] [直角坐标系] School of Mechanical Engineering ME369-lecture 7.2 Shanghai Jiao Tong University Fall 2015 环节的频率响应-增益环节/放大环节 G(jo)=K L(@)=201g K G(j@)FU-(@)+V2(@)=K p(o)=0° ∠G(jo)=arctan V(@) U(a) 14420 0 201gK Im 20 180 0 -90 -180 0 K Re 0 10 10 10 (rad/sec) School of Mechanical Engineering ME369-lecture 7.2 Shanghal Jiao Tong University Fall 2015 22015/11/14 2 BE315-Lecture 7.2 Fall 2011 ME369-lecture 7.2 Fall 2015 School of Mechanical Engineering Shanghai Jiao Tong University 尼奎斯特图(Nyquist plot、polar plot）定义 [极坐标系] [直角坐标系] --（ 对数幅频图） | ( ) | G j VS G j ( )  BE315-Lecture 7.2 Fall 2011 ME369-lecture 7.2 Fall 2015 School of Mechanical Engineering Shanghai Jiao Tong University G j K ( )   2 2 | ( ) | ( ) ( ) G j U V K       ( ) ( ) arctan[ ] ( ) V G j U      L K ( ) | 20lg    ( ) 0  环节的频率响应--增益环节/放大环节