2 u=L (t) ()d dt L L u L 21(t) n(9)d+()dl L Jo =i1(0)+0u(5)l L =Liw()=v(0)+u(4)dl 当为有限值时40)=( y(0)=y2(0)磁链守恒 结论换路瞬间,若电感电压保持为有限值, 则电感电流(磁链)换路前后保持不变。□t i u L L d d = =   − ( )d 1 ( ) t L u L i t =   +     − − − ( ))d 1 ( )d 1 ( ) 0 0 t L u L u L i t u  d L i t L ( ) 1 (0 ) 0 = + − − 当u为有限值时  =  +    − − ( ) (0 ) ( )d 0 t t u  = LiL L (0+ )= L (0- ) iL (0+ )= iL (0- ) 磁链守恒 i u L + - L 结论 换路瞬间，若电感电压保持为有限值， 则电感电流（磁链）换路前后保持不变。 2