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填空题解析

1、解析:上升时间,超调量,稳态误差,调节时间,超调量,稳态误差

2、解析:\(\Phi(s) = \dfrac{1}{10s(3s+1)}\)

3、解析:0

4、解析:\(\dfrac{1}{4}\) \(\infty\)

5、解析:左侧

6、解析:\(4e^{-2t}\) \(2t+e^{-2t}-1\) \(\dfrac{4}{s+2}\)

7、解析:复变函数

8、解析:\(r=\begin{cases}t & t\geqslant 0\\0 & t<0\end{cases}\)

9、解析:稳态误差

10、解析:\(\xi, w_n\)

11、解析:过阻尼系统

12、解析:

\[G(s) = \frac{1}{s^2}+\frac{0.9}{s}-\frac{0.9}{s+10} = \frac{s+10+0.9s(s+10)-0.9s^2}{s^2(s+10)} = \frac{10s+10}{s^2(s+10)}\]
\[R(s) = \frac{1}{s}+\frac{1}{s^2} = \frac{s+1}{s^2}\]

\(\Phi(s) = \dfrac{c(s)}{R(s)} = \dfrac{10s+10}{s^2(s+10)}\times\dfrac{s^2}{s+1} = \dfrac{10}{s+10}\) 单位负反馈\(H(s)=1\)

\[\Phi(s) = \frac{G(s)}{1+G(s)} \rightarrow (1+G)\Phi = G \rightarrow G(\Phi-1) = -\Phi \rightarrow G = \frac{\Phi}{1-\Phi}\]
\[G = \frac{\dfrac{10}{s+10}}{1-\dfrac{10}{s+10}} = \frac{\dfrac{10}{s+10}}{\dfrac{s+10-10}{s+10}} = \frac{10}{s}\]

\(\Phi(s) = \dfrac{1}{1+\dfrac{10}{s}} = \dfrac{s}{s+10}\),故 \(\lim\limits_{s\to\infty} s\cdot\left[\dfrac{s}{s+10}\cdot\dfrac{s+1}{s^2}\right] = \lim\limits_{s\to\infty}\dfrac{s-1}{s+10} = 0.1\)

13、解析:\(T=0.01, K=1\)

\[G(s) = \frac{K(1-0.5s)}{s(Ts+1)} \Rightarrow \phi(s) = \frac{G(s)}{G(s)+1} = \frac{K(1-0.5s)}{s(Ts+1)+K(1-0.5s)}\]
\[= \frac{K(1-0.5s)}{Ts^2+(1-0.5K)s+K}\]

由题干可知,\(\omega = 10\)