当uc(0+)=Uo,(0+)=0时 (t) Uo st S,Uo U i(t)=C duc(t) dt l(s,s eat di (t)=L dt S t>0( ) - 1 2 2 1 1 0 2 1 2 0 s t s t C e s s s U e s s s U u t － － ＝ 当uC (0+)=U0 ,iL (0+)= 0时 ( - ) d ( ) d ( ) ( ) 1 2 2 1 C 0 s t s t e e L s s U t u t i t C － = ＝ ( -s ) d d ( ) 1 2 1 2 2 1 0 s t s t L s e e s s U t i u t L － ＝ = t > 0