**Cascade Compensation in Time Domain**

**1. A proportional controller leads to:**

a) Zero steady state error for step input for type 1 system

b) Zero steady state error for step input for type 0 system

c) Infinite steady state error for step input for a type 1 system

d) Finite steady state error for step input for type 1 system

**Answer:** a

**Explanation:** A proportional controller is the controller block used in the system so as to follow the output and leads to zero steady state error for step input for type 1 system.

**2. An all-pass network imparts only**

a) Negative phase to the input

b) Positive phase to the input

c) 90 degree phase shift to the input

d) 180 degree phase shift to the input

**Answer:** d

**Explanation:** An all-pass network is the network that is the combination of the minimum and non-minimum phase systems and have the magnitude 1 for all frequencies and imparts only 180 degree phase shift.

**3. Which of the following is an effect of lag compensation?**

a) Decrease bandwidth

b) Improves transient response

c) Increases the effect of noise

d) Increases stability margin

**Answer:** a

**Explanation:** Lag compensation is the integral compensation that introduces the lag in the response by slowing the response and reducing the steady state error value by decreasing bandwidth.

**4. PD controller:**

a) Decreases steady state error and improves stability

b) Rise time decreases

c) Transient response becomes poorer

d) Increases steady state error

**Answer:** b

**Explanation:** In Proportional and Derivative controller the damping factor value is increases the oscillations are reduced and rise time decreases hence speed of response increases.

**5. PID controller:**

a) Decreases steady state error and improves stability

b) Rise time decreases

c) Transient response becomes poorer

d) Increases steady state error

**Answer:** a

**Explanation:** Proportional Integral and Derivative controller is the controller that is the combinational controller that increases the speed of response, decreases steady state error and improves stability.

**6. PI controller:**

a) Decreases steady state error and improves stability

b) Rise time decreases

c) Transient response becomes poorer

d) Increases steady state error

**Answer:** c

**Explanation:** In Proportional and Integral controller which is the extension of the integral controller which improves the steady state response but transient response becomes poorer.

**7. Proportional controller**

b) Rise time decreases

c) Transient response becomes poorer

d) Increases steady state error

**Answer:** d

**Explanation:** Proportional controller is the controller that is used in the system so that the output follows the input and increases steady state error.

**8. PD controller is used to compensate a system, Compared to the uncompensated system, the compensated system has:**

a) A higher type number

b) Reduced damping

c) Higher noise amplification

d) Large transient overshoot

**Answer:** c

**Explanation:** The compensated system of the proportional derivative controller has bandwidth increases and signal to noise ratio decreases.

**9. Lead compensator increases bandwidth**

a) True

b) False

**Answer:** a

**Explanation:** Lead compensator is similar to high pass filter and causes lead in the system and increases the speed of response of the system and hence increases Bandwidth.

**10. Lag compensator reduces__________**

a) Position constant

b) Velocity constant

c) Position variable

d) Acceleration constant

**Answer:** b

**Explanation:** Lag compensator is the integral compensation that causes the lag in the response and reduces velocity constant.