式中 小(s)=s2+4s+3=(s+1X+3)=0为特征方程4(s)=S 3/2-1/2 11/32/3 Y(S)+Y2(S)+y,(s) (S+1)(s+3)L(s+1)(+3) 输出响应为 pm=/3 2 e le t-e 2 系统稳态响应为 1()2 t→> 3 MODERN CONTROL SYSTEMMODERN CONTROL SYSTEM 9 ( ) 4 3 ( 1)( 3) 0 2 q s = s + s + = s + s + = 式中 为特征方程 d(s) = s ( ) ( ) ( ) 2 / 3 ( 3) 1/ 3 ( 1) 1 ( 3) 1/ 2 ( 1) 3/ 2 ( ) 1 2 3 Y s Y s Y s s s s s s Y s + = + +       + + + − +      + − + + = 输出响应为 3 2 3 1 1 2 1 2 3 ( ) 3 3 +      + − +       = − −t − t −t − t y t e e e e 3 2 lim ( ) = → y t t 系统稳态响应为