3.方框图的描述与转换1-串联 设本节中传递函数G1(s)、G2(s)分别为 G 1 ( s ) = b m s m + b m − 1 s m − 1 + . . . + b 1 s + b 0 a n s n + a n − 1 s n − 1 + . . . + a 1 s + a 0 G_1(s)=\frac{b_ms^m+b_{m-1}s^{m-1}+...+b_1s+b_0}{a_ns^n+a_{n-1}s^{n-1}+...+a_1s+a_0} G1(s)=ansn+a