Push Hs Right Fbb9Fb
1. **Problem Statement:**
We have a control system with forward path transfer function $G(s) = \frac{s+1}{s(s+2)}$ and feedback path transfer function $H(s) = \frac{s+3}{s+4}$. The system has a negative feedback loop.
2. **Goal:**
Push $H(s)$ to the right past the summing junction and find the equivalent system.
3. **Key Concept:**
When moving a block past a summing junction, the transfer functions must be adjusted to maintain the same overall system behavior.
4. **Original system:**
The output $Y(s)$ is given by:
$$Y(s) = G(s) \cdot \left(R(s) - H(s)Y(s)\right)$$
5. **Rearranging:**
$$Y(s) + G(s)H(s)Y(s) = G(s)R(s)$$
$$Y(s)(1 + G(s)H(s)) = G(s)R(s)$$
$$\Rightarrow \frac{Y(s)}{R(s)} = \frac{G(s)}{1 + G(s)H(s)}$$
6. **Moving $H(s)$ past the summing junction:**
To push $H(s)$ to the right, we redefine the system so that the summing junction subtracts $Y(s)$ multiplied by a new function $H_{new}(s)$ after $G(s)$.
7. **Equivalent system:**
The new feedback function after $G(s)$ is:
$$H_{new}(s) = G(s)H(s)$$
8. **Calculate $H_{new}(s)$:**
$$H_{new}(s) = \frac{s+1}{s(s+2)} \times \frac{s+3}{s+4} = \frac{(s+1)(s+3)}{s(s+2)(s+4)}$$
9. **Final equivalent system:**
- Forward path: $G(s)$ remains the same.
- Feedback path after $G(s)$: $H_{new}(s) = \frac{(s+1)(s+3)}{s(s+2)(s+4)}$.
This means the summing junction now subtracts $H_{new}(s)Y(s)$ after $G(s)$.
**Answer:**
The equivalent system has the same $G(s)$ block, and the feedback block moved to the right with transfer function:
$$H_{new}(s) = \frac{(s+1)(s+3)}{s(s+2)(s+4)}$$