解：本结构图有2条前向通道，6个回路(其中I，V两回路不相交)
??1?{?H?G2?G1?G1G2?(?G3)?[?(?G3)]}?[?(?G3)].(?H) ?1?H?G2?G1?G1G2?G3Hp1?G1G2 ;?1?1p2??G3 ;?2?1?HG1G2?G3 (1?H)? ?(s)?1?H?G2?G1?G1G2?G3H
? 求L???t??
解：???t??1??t?
?L???t???L?1??t???s????0???1?0?1 ? 求L?cos?t?
解：L?cos?t??
11s
?L?sin??t??1??s??s? s2??2s2??2