102年 - 102 國立中山大學_碩士班招生考試_電機系(乙組)：控制系統#110070

科目：中山◆電機◆控制系統 | 年份：102年 | 選擇題數：0 | 申論題數：10

試卷資訊

所屬科目：中山◆電機◆控制系統

選擇題 (0)

申論題 (10)

(a) (10%) Find the transfer function of the system.

(b) (10%) Find the zero-input response y(t).

(c) (10%) Choose, among the following types of control, ones that are likely to stabilize the system (One or more answers may be correct. Answers without supporting explanation are not acceptable) : (i) P control (ii) I control (iii) D control (iv) PID control (v) PD control (vi) PI control

(d) (10%) Choose, among the following types of control, ones that are likely to regulate the system output to a constant level 0.5 with zero steady state error (One or more answers may be correct. Answers without supporting explanation are not acceptable): (1) P control (ii) I control (iii) D control (iv) PID control (v) PD control (vi) PI control

(a) (10%) Derive a state-space representation of this LCR circuit.

(b) (10%) Suppose L =C=R=1 and x₁(0)=x₂(0)=1. What is the output y in steady state if u =sin(t)?

(c) (10%) Following 2(b), let the control be u(t)=-k₁x₁(t)-k₂x₂(t). Choose the gains k₁ and k₂ such that the closed loop poles are -2 and -3.

(a) (10%) Use Laplace transform to derive the transfer function from e(t) to e(t-D).

(b) (10%) Estimate the maximum allowable delay for the system to maintain at least 20 dB of gain margin, by using the approximation , when |ω|<<1.

PROBLEM 4 (10%) After dozing off in the Monday morning class, your classmate asked you: "Integral control adds negative phase, thus decreasing the phase margin. Why would we ever want to use integral control?" Explain how you would answer him. system.