传递函数的简化

串联

并联

反馈

\begin{aligned} [R (s) - C (s) H (s)] G (s) = C (s) \\ R (s) G (s) = C (s) [1 + H (s) G (s)] \\ \frac{C (s)}{R (s)} = \frac{G (s)}{1 + H (s) G (s)} \end{aligned}

单位负反馈

\begin{array}{r} \frac{G (s)}{1 + G (s)} = \frac{\frac{A}{B}}{1 + \frac{A}{B}} = \frac{A}{A + B} \end{array}

负反馈

\begin{array}{r} \frac{G (s)}{1 + G (s)} = \frac{\frac{A}{B}}{1 + \frac{A}{B} * C} = \frac{A}{A C + B} \end{array}