系统的闭环传递函数为 C(s G(S) R(S)1+G(SH(S) →根轨迹方程(系统闭环特征方程)为 +G(S)H(s)=0→GH()=-1 KII(s-2) G(SH(S) =-1=1∠(2k+1)x ∏(s-p)( ) 1 1 ( ) ( ) ( ) 1 1 2 1 ( ) m j j n i i K s z G s H s k s p  = = − = = − =  + −    1 ( ) ( ) 0 ( ) ( ) 1 + =  = − G s H s G s H s 根轨迹方程（系统闭环特征方程）为 系统的闭环传递函数为 1 ( ) ( ) ( ) ( ) ( ) G s H s G s R s C s + =